Next Article in Journal
Emerging Therapeutic Potential of Polyphenols from Geranium sanguineum L. in Viral Infections, Including SARS-CoV-2
Previous Article in Journal
Mitochondria Play Essential Roles in Intracellular Protection against Oxidative Stress—Which Molecules among the ROS Generated in the Mitochondria Can Escape the Mitochondria and Contribute to Signal Activation in Cytosol?
Previous Article in Special Issue
Hypoxia-Induced Changes in L-Cysteine Metabolism and Antioxidative Processes in Melanoma Cells
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Biomolecules
Volume 14
Issue 1
10.3390/biom14010129
biomolecules-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Review

Hydrogen Sulfide (H2S)/Polysulfides (H2Sn) Signalling and TRPA1 Channels Modification on Sulfur Metabolism

by
Hideo Kimura
Department of Pharmacology, Faculty of Pharmaceutical Sciences, Sanyo-Onoda City University, 1-1-1 Daigaku-Dori, Sanyo-Onoda 756-0884, Yamaguchi, Japan
Biomolecules 2024, 14(1), 129; https://doi.org/10.3390/biom14010129
Submission received: 19 December 2023 / Revised: 11 January 2024 / Accepted: 17 January 2024 / Published: 19 January 2024
(This article belongs to the Special Issue H2S, Polysulfides, and Enzymes: Physiological and Pathological Aspects 2.0)
Browse Figures
Review Reports Versions Notes

Abstract

:
Hydrogen sulfide (H2S) and polysulfides (H2Sn, n ≥ 2) produced by enzymes play a role as signalling molecules regulating neurotransmission, vascular tone, cytoprotection, inflammation, oxygen sensing, and energy formation. H2Sn, which have additional sulfur atoms to H2S, and other S-sulfurated molecules such as cysteine persulfide and S-sulfurated cysteine residues of proteins, are produced by enzymes including 3-mercaptopyruvate sulfurtransferase (3MST). H2Sn are also generated by the chemical interaction of H2S with NO, or to a lesser extent with H2O2. S-sulfuration (S-sulfhydration) has been proposed as a mode of action of H2S and H2Sn to regulate the activity of target molecules. Recently, we found that H2S/H2S2 regulate the release of neurotransmitters, such as GABA, glutamate, and D-serine, a co-agonist of N-methyl-D-aspartate (NMDA) receptors. H2S facilitates the induction of hippocampal long-term potentiation, a synaptic model of memory formation, by enhancing the activity of NMDA receptors, while H2S2 achieves this by activating transient receptor potential ankyrin 1 (TRPA1) channels in astrocytes, potentially leading to the activation of nearby neurons. The recent findings show the other aspects of TRPA1 channels—that is, the regulation of the levels of sulfur-containing molecules and their metabolizing enzymes. Disturbance of the signalling by H2S/H2Sn has been demonstrated to be involved in various diseases, including cognitive and psychiatric diseases. The physiological and pathophysiological roles of these molecules will be discussed.

1. Introduction

Since the discovery of H2S as environmental toxic gas by Ramazinni in 1713, many studies have been devoted to its toxicity. Survivors from the exposure to high concentrations of H2S suffered from mental dysfunction, suggesting that the brain must be a target of H2S. Warenycia et al. discovered a certain amount of H2S existed in the brain [1]. This observation suggested that endogenous H2S may have a physiological role in mammals.
The toxic effect of high concentrations of H2S on the levels of neurotransmitters has been studied. Exposure of rats to high levels of H2S during perinatal development significantly decreases neurotransmitter levels [2]. Sublethal doses of NaHS chronically applied to rodents suppressed neurotransmitter levels [3]. However, the effect of endogenous levels of H2S on neurotransmitters release has not yet been well understood.
Cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE), which catalyse a pathway to produce cysteine, also play a role in producing H2S [4,5,6]. Although CSE levels are very low in the brain, it plays an important role under pathological conditions such as Alzheimer’s disease and Huntington’s disease [7,8,9]. 3MST produces not only H2S but also polysulfides, including H2Sn [10,11,12]. Cysteine aminotransferase (CAT) metabolizes L-cysteine and α-ketoglutarate to produce 3-mercaptopyruvate (3MP), which is the substrate of 3MST. 3MP is also produced from D-cysteine by D-amino acid oxydase [13]. The high levels of D-cysteine recently identified in embryonic brain suggest that this pathway plays an important role especially in the developing brain [13,14]. CBS is localized to astrocytes, and 3MST to both neurons and glia in the brain [10,15,16].
Several other enzymes can also produce polysulfides, including sulfur quinone oxidoreductase (SQR), myoglobin, neuroglobin, catalase, superoxide dismutase (SOD), myeloperoxidase, and cysteinyl tRNA synthetase (CARS) [17,18,19,20,21,22,23]. The chemical interaction of H2S with NO also produces polysulfides that have been predicted from the finding of synergistic effect of H2S and NO on vascular relaxation [6,24,25,26,27,28,29,30,31,32].
The first step of the metabolism of H2S is the reduction of the cysteine disulfide bond of sulfide quinone oxidoreductase (SQR) in mitochondria [33] (Figure 1a). It is predicted that the reduction of the cysteine disulfide bond may cause conformational changes in target proteins. Dithiothreitol (DTT) enhances the activity of NMDA receptors by reducing the cysteine disulfide bond at the ligand binding domain of the receptors [34]. H2S facilitates the induction of hippocampal long-term potentiation (LTP), a synaptic model of memory formation, by enhancing the activity of N-methyl-D-aspartate (NMDA) receptors [5] (Figure 1b).
It has been extensively studied that S-sulfuration (S-sulfhydration), an addition of sulfur to thiol, modified the activity of enzymes, including cystathionine synthase-serine dehydratase, aldehyde oxidase, and adenylate kinase [36,37,38]. S-sulfuration has been proposed as a mode of action of H2S [39]. The activity of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) was increased via S-sulfuration by H2S [39].
TRP channels are known to be sensitive to various stimuli including heat and pungent substances including H2Sn to induce Ca2+ influx in cells [11]. We, together with others, have recently reported that TRPA1 and TRPV1 are involved in the metabolism of sulfur-containing substances including methionine and cysteine [40,41]. They even regulate the transcription or translation of 3MST, rhodanese (TST), and persulfide dioxygenase or ethylmalonic encephalopathy protein 1 (ETHE1) [41,42]. It is intriguing to clarify the mechanism for the regulation of the sulfur metabolism by the channels.

2. Endogenous H2S, Its Production, and Its Metabolism

Warenycia et al. detected H2S by the methylene blue method, in which the reaction mixture contains high concentrations of acids that make brain homogenates release great amounts of H2S from the iron-sulfur cluster attached to enzymes belonging to the respiratory chain, including aconitase [1,43]. For this reason, the endogenous levels of free H2S with this method were over-estimated. Two other groups also measured H2S levels in the brains of humans and bovine with a similar method, which showed 50–160 μM [44,45].
Since then, several methods were applied to measuring endogenous H2S, and the lowest level estimated in the brain was 14 nM [46]. In their method, the tissue was homogenized with phosphate buffer, and released H2S from homogenates was measured by gas chromatography. Because free H2S is re-absorbed by the tissue homogenates as sulfane sulfur [43], the value obtained with this method was underestimated.
H2S and polysulfides have been measured as their monobromobimane (mBB) adducts by HPLC and LC-MS/MS. The labelling reaction with mBB has been performed under alkaline conditions (pH 8.4–9.5), where the exchange between H2S and polysulfides shifts more to H2S than to polysulfides, resulting in the overestimation of H2S levels and the underestimation of polysulfide levels [47]. We derivatized H2S and polysulfides with mBB at physiological pH 7.0. Recent evaluation of H2S using LC-MS/MS showed 0.030 ± 0.004 μmol/gram protein, which is approximately 3 μM in the brain [48]. Even with this method, both intracellular and extracellular molecules react with each other at homogenization, which causes extracellular cystine to be reduced to cysteine, which reacts with intracellular enzymes to generate H2S.
CBS produces H2S from L-cysteine and L-homocysteine. The activity of CBS is regulated by S-adenosyl methionine (SAM), NO, and CO [5,49,50,51]. SAM binds to the site located at the carboxy-terminus of CBS to enhance the activity, while NO and CO bind to the heme group located at the amino-terminus to suppress the activity (Figure 2). This regulation has an important role under hypoxic conditions in the brain. Under hypoxia, CO production is decreased, leading to the enhancement of CBS activity in astrocytes surrounding capillaries, which are dilated by produced H2S to restore blood flow [52]. Overproduction of H2S in hypoxia, in turn, suppresses mitochondrial cytochrome oxidase, leading to damage in the brain; the damage can be decreased depending on the levels of SQR [53]. However, the levels of SQR have been reported to be very low in the brain [54]. To compensate for the low levels of SQR, neuroglobin has been predicted to play a role in H2S oxidation in the brain [19].
CBS was reported to be also localized to neurons using the polyclonal antibody preincubated with CBS knockout mouse brain extract to mask any nonspecific immunoreactivity [55]. However, not only our antibody but also the same antibody as mentioned by Robert et al., after affinity purification, detected CBS in astrocytes but not in neurons [15].
CSE produces H2S under physiological low concentrations of Ca2+, while its activity is suppressed by high concentrations of Ca2+ [56]. Once intracellular concentrations of Ca2+ are increased in stimulated cells, H2S production by CSE can be decreased. The levels of CSE are also transcriptionally regulated. The promoter region of the CSE gene has an SP-1 binding site, and the expression of CSE is enhanced three times by tumour necrosis factor α, which enhances the binding of SP1 [7,57].
3MST produces H2S from 3MP, a product of CAT from L-cysteine and α-keto glutarate [10,58,59,60]. The active-site cysteine residue of 3MST receives sulfur from 3MP, then S-sulfurated active-site cysteine residue of 3MST releases H2S via reduction by thioredoxin (Figure 3) [61,62]. 3MST is localized to the cytoplasm as well as to mitochondria, in which the level of cysteine is sufficiently high (approximately 1 mM) to produce H2S [63,64].
Propargylglycine and β-cyano-L-alanine have been used to inhibit the activity of CSE, and aminooxyacetic acid inhibits CBS [4,66,67,68]. Recently, a specific inhibitor of 3MST has been developed by Hanaoka et al. (2017) by high-throughput screening of a large chemical library (174,118 compounds). Their compound 3 with aromatic ring-carbonyl-S-pyrimidone structure specifically interacts with the persulfur anion of the S-sulfurated cysteine residue of 3MST to suppress the production of H2S and polysulfides [69].

3. Bound Sulfane Sulfur and S-Sulfurated Proteins

In tissues, there are forms of sulfur, sulfane sulfur, which release H2S under reducing conditions [3,43,70]. They include H2Sn, Cys-SSH, GSSH, and P-SSH. Warenycia et al. identified the non-acid labile H2S liberated by DTT from brains of H2S-poisoned animals [3], and it was later called bound sulfur [70]. The levels as well as the characteristics of bound (sulfane) sulfur are different between tissues. Homogenates of the liver released H2S, which was increased and reached its maximum at one hour (approximately 6 μmol H2S/g protein) and then decreased abruptly after 2 h of DTT application. In contrast, those of the brain gradually increased H2S release up to 5 h after DTT addition (approximately 2 μmol H2S/g protein) [43]. Homogenates of the heart released H2S just less than approximately 0.2 μmol H2S/g protein for the first two hours, then stopped releasing.
The absorption rates of H2S are also different between tissues. Liver homogenates promptly absorbed H2S, while those of hearts took 10 min to completely absorb it and those of brains took 30 min [43]. The interesting thing to note is that heart homogenates released a little H2S by DTT, while it absorbed H2S well, suggesting that cysteine residues may be highly oxidized in this tissue, or that the abundant iron reacts with H2S. These observations indicate that each tissue has the specific forms of sulfane sulfurs, which have the characteristics of a different rate of H2S release and absorption, probably due to having the different redox states.

4. Production of H2Sn and Other S-Sulfurated Molecules

Endogenous H2Sn have been identified in the brain [11,48]. 3MST produces H2Sn and other S-sulfurated molecules, such as cysteine persulfide (Cys-SSH), glutathione persulfide (GSSH), and S-sulfurated cysteine residues of proteins (P-SSH) [12,71]. Two possible mechanisms have been proposed. Sulfur is transferred from S-sulfurated active cysteine residues of 3MST to the acceptor molecules such as H2S, cysteine, glutathione, and cysteine residues, to produce corresponding S-sulfurated molecules (Figure 4a) [12,71]. Alternatively, 3MST produces H2S2, which reacts with cysteine, glutathione, and cysteine residues to generate their S-sulfurated molecules (Figure 4b) [12,71]. In the latter mechanism, H2S2 has an advantage in easily accessing targets with less steric hindrance comparing with 3MST itself, but less specific to the target molecules. Recently, 3MST was shown to directly transfer sulfur to cysteine residues using 3MST fused with redox-sensitive green fluorescent protein, which has two thiol groups on its surface and acts as a highly efficient sulfur acceptor from 3MST [72].
Two mechanisms have been proposed for S-nitrosylation of proteins by NO (Figure 5). NO is defused to the target proteins to S-nitrosylate them (Figure 5a) [74]. Another mechanism is that NO-synthase makes a complex with S-nitrosylase to S-nitrosylate their target proteins (Figure 5b) [75]. Considering these mechanisms for S-nitrosylation, S-sulfuration may also be mediated, both by the diffusion of small sulfur molecules such as H2S and H2Sn as well as by enzymes including 3MST.
3MST is also known as tRNA thiouridine modification protein [76,77]. 3MST transfers sulfur from 3MP to uridine of tRNA that provides accurate deciphering of the genetic code and stabilizes the structure of tRNA [77,78,79]. Cysteinyl tRNA synthetase (CARS) has been found to transfer sulfur from one cysteine to another to produce Cys-SSH [23].
The intracellular concentrations of H2S are well regulated by a balance of its production and clearance [80,81]. SQR receives sulfur from H2S to its active-site cysteine to produce persulfide (Figure 1a), whose sulfur, in turn, has been proposed to be transferred to H2S, cysteine, and GSH to produce H2S2, Cys-SSH, and GSSH, respectively [17]. Haemoglobin and myoglobin localized to blood and muscle, respectively, oxidize H2S to H2Sn [18,81]. Neuroglobin, another haemoprotein located in neurons, also oxidizes H2S to H2Sn [19].
Catalase, which is highly S-sulfurated and may be regulated by H2S, H2Sn, and other S-sulfurated molecules [39], oxidizes H2S to produce H2Sn [20]. Copper/zinc super oxide dismutase (SOD) generates H2Sn by oxidizing dissolved H2S gas rather than HS− in the presence of O2 and H2O2 [21,82,83]. Mitochondrial manganese SOD can also oxidize H2S to H2Sn. Peroxidases such as lactoperoxidase and myeloperoxidase oxidize H2S to H2Sn in the presence of H2O2 [22,84].
CSE has been proposed to be able to produce Cys-SSH from cystine [85], and CBS was recently added to a group of enzymes to have a similar activity to CSE [86]. Both CSE and CBS are localized to cytoplasm, where cystine levels are approximately 0.20 and 0.05 μM in the liver and lung, respectively, and under detectable levels in the brain and heart, while the Km value of CSE to cystine is 30 to 70 μM [86,87]. If the intracellular cystine concentrations are above 5 μM, CSE may have a possibility to synthesize Cys-SSH in cells [88]. It was recently reported by the same group that the production of H2S, H2Sn, Cys-SSH, and GSSH was not changed in mice with triple knock-out of CBS, CSE, and 3MST [89].

5. H2Sn Production by the Chemical Interaction between H2S and NO

H2S relaxes vascular smooth muscle in synergy with NO [6], and a similar synergistic effect was observed in intestine [90]. H2S2 and H2S3 are produced from H2S and NO [31,32]. H2Sn exist in the brain as products of oxidized H2S as well as those generated by 3MST [11,12,48].
As a mechanism for the generation of H2S2 from H2S and NO, NO is oxidized to N2O3, which reacts with H2S to generate HSNO. HSNO, in turn, reacts with H2S to produce H2S2 [29,91].
2NO + O2 = 2NO2
NO2 + NO = N2O3
N2O3 + H2S = HSNO + H + NO2−
HSNO + H2S = HSSH + HNO
Alternatively, one electron oxidation of HS− generates thiyl radical (HS•), which readily react with NO radical to produce HSNO.
HS− = HS• + e−
HS• + NO• = HSNO
The production of H2Sn has also been demonstrated in peritoneal mast cells, where the application of H2S donor GYY4137 [92] and NO donor DEA NONOate reacted with endogenous NO and H2S, respectively, in the cells, and the products were detected by a polysulfide-sensitive fluorescent probe SSP4 [31,93]. The potential products, H2Sn, were detected by the activation of Ca2+ channels in mast cells.
Ebenhardt et al. proposed that nitroxyl (HNO) together with H2Sn are produced by the interaction of H2S with NO, and that HNO is a major product which activates TRPA1 channels [29]. The product from the interaction between H2S and NO as well as H2Sn are degraded by cyanide, while HNO is resistant, suggesting that H2Sn may be a preferable chemical entity to HNO to activate TRPA1 channels [32]. Cortese-Krott et al. reported the generation of SSNO−, H2Sn, and dinitrososulfite from the interaction of H2S with NO [30]. The products from H2S and NO as well as H2Sn are degraded by reduction, while SSNO− is resistant to reduction [30,32]. Based on these observations, we suggested that H2Sn are the potential products [32]. Recently, Bogdandi et al. reported that H2Sn is less stable compared to SSNO− and suggested that H2Sn transiently activate TRPA1 channels at the early phase of the production of these substances, while more stable SSNO− induces sustained activation of the channels [94].

6. S-Sulfuration of Cysteine Residues by H2Sn

Sulfur atoms with the same oxidation state are not able to react with each other. Because the oxidation state of both sulfur atoms in H2S and that in cysteine is −2, they do not react with one another. In contrast, in H2Sn, the oxidation state of sulfur atoms is 0 or −1. TRPA1 channels were found to be activated by H2S, and it was later identified that H2Sn activate the channels more efficiently than H2S [11,95,96,97]. TRPA1 channels have 31 cysteine residues, and 21 are localized to the amino terminus [98]. Cys422 and Cys634 are sensitive to H2Sn to be S-sulfurated [99]. One of the two cysteine residues may be S-sulfurated and reacts with another to make a disulfide bond to induce the conformational changes to activate the channels (Figure 6) [12]. Alternatively, two cysteine residues are S-sulfurated at the same time. The former may more efficiently change the conformation of the channels. The activity of tumour suppressor PTEN is modified by H2Sn through two cysteine residues, Cys71 and Cys124, forming a disulfide bond [100]. A monomer protein kinase G1α (PKG1α) is inactive, while the formation of a cysteine disulfide bond between each Cys42 through S-sulfuration by H2Sn makes the active homodimer (Figure 6) [101].
ATP-dependent K+ channels are activated through S-sulfuration of Cys43 in its Kir subunits by H2S [102]. Cys43 is located at the critical site for the binding to ATP, and the subtle conformational change by S-sulfuration may cause the dramatic changes in binding of the channels to ATP. Cys43 is exposed to the cytoplasmic side of cells, and if it is Cys-SH form, H2Sn rather than H2S S-sulfurate it. In contrast, if Cys43 is in Cys-SNO or Cys-SOH form, H2S is preferable to H2Sn to S-sulfurate it. The other example is GAPDH [39,103]. The activity of GAPDH was initially reported to be increased via S-sulfuration by H2S [39]. However, it was later reported that H2S had no effect on GAPDH activity, while H2Sn inhibited GAPDH [103]. The possible mechanism is discussed in the next section.

7. S-Sulfuration of S-Nitrosylated or S-Sulfenylated Proteins by H2S

The human cysteine proteome includes 214,000 cysteine residues and 5–12% of total cysteine residues are oxidized, including the cysteine disulfide bond (P-S-S-P), P-SNO, P-SOH, and P-SSH [104]. It has been predicted from the fact that tissues contain bound (sulfane) sulfur [3,43,70,105]. Mustafa et al. identified 39 S-sulfurated proteins, including GAPDH, β-tubulin, and actin, in liver lysates [39].
The oxidation state of sulfur in these oxidized cysteine residues is −1 or 0, and they are able to react with H2S. P-S-S-P, P-SNO, and P-SOH cysteine residues are reduced by H2S to P-SSH, which is further reduced to P-SH. When H2S and NO are generated at a restricted area in cells, either one of two reactions may occur: H2S2 is produced from H2S and NO, and then S-sulfurate P-SH to P-SSH. Alternatively, NO reacts with cysteine residues to generate P-SNO, which is reduced by H2S to P-SSH.
Some cysteine residues may have specificity to the reaction with NO, while others react with little preference. For example, among around 100 cysteine residues in the skeletal muscle ryanodine receptor, many of them are oxidized, but only one of them is S-nitrosylated [106]. In parkin, of which the mutations cause Parkinson’s disease, Cys95, Cys59, and Cys 182 are S-sulfurated in the brains of normal individuals, while they are S-nitrosylated in those of patients [107]. Two cysteine residues of the amino terminus of TRPA1, Cys 422, and Cys634 in mouse are responsible for activation by H2S2 and H2S3 [11,32,99], while the human equivalence Cys421 and Cys633 have been reported to be sensitive to O2 [108]. Cys 421 in human is also modified by NO and H2O2 [109].
H2O2 reacts very slowly with free cysteine (2–20 M−1·s−1). In contrast, its reactivity significantly increases to cysteine residues (10–106 M−1·s−1) [110]. Although H2O2 poorly reacts with H2S (0.73 M−1·s−1), P-SOH react two orders of magnitude faster with H2S than with glutathione at pH 7.4 [111,112]. The activation of receptor tyrosine kinase enhances the production of H2O2 and the subsequent S-sulfenylation of target proteins [113,114]. Zivanovic et al. demonstrated that the application of epidermal growth factor (EGF) to cells induced dramatic increase in the levels of P-SOH, and then they decreased [115]. At the decreasing phase of P-SOH, the levels of P-SSH started increasing. This correlates well with the increase in the expression of CBS, CSE, and 3MST, suggesting that P-SOH efficiently reacts with H2S to produce P-SSH.

8. H2S and H2Sn in Neuronal Transmission

The other gaseous signalling molecules, NO and CO, are recognized as retrograde neurotransmitters, which are released from postsynapse to presynapse to facilitate the release of a neurotransmitter glutamate, to induce hippocampal LTP [116,117,118,119,120,121]. When postsynaptic NMDA receptors are activated by glutamate, Ca2+ enters cells through NMDA receptors and makes Ca2+/calmodulin complex, which activate NO synthetase (NOS) to release NO. NO diffuses to the presynapse, where it activates soluble guanylyl cyclase to produce cGMP, which activates G-kinase to modulate the release of neurotransmitter glutamate, leading to facilitating LTP induction [122,123].
As described previously, the enhancement of NMDA receptor activity through its reduction was not the only mechanism for the facilitation of LTP induction by H2S. Although the reducing activity of H2S is weaker than that of DTT, H2S more efficiently facilitated the induction of LTP than DTT [5], suggesting an additional mechanism for facilitating LTP induction.
We found that H2S activates astrocytes to induce Ca2+ influx via the TRP family of channels [96], and Streng et al. identified that TRPA1 channels in the bladder are activated by H2S [97]. H2Sn have much higher potency than H2S to induce Ca2+ influx by activating TRPA1 channels in astrocytes [11,95,96,97,124,125]. Endogenous H2S2, H2S3, cysteine per- and poly-sulfide, and glutathione per- and poly-sulfide were identified in the brain [11,12,48,71,126], and the garlic-derived organic polysulfides dimethyl trisulfide (DMTS) and diallyl trisulfide (DATS) also activate TRPA1 channels [11]. Shigetomi et al. reported that the activation of TRPA1 channels induced the release of D-serine, a coagonist of NMDA receptors, from astrocytes to facilitate the induction of LTP [127]. Based on these observations, the additional mechanism for LTP induction was predicted to be the activation of TRPA1 channels in astrocytes by H2Sn to induce a release of D-serine [11,127,128]. Recently, however, D-serine was reported to be mainly released from neurons, to which TRPA1 channels are not localized, and that the contribution of astrocytes to release D-serine is minor [129]. It was necessary to re-evaluate the involvement of TRPA1 channels in the release of D-serine from astrocytes. Recent findings are discussed in the next section.

9. The Release of Neurotransmitters by H2S and H2Sn

Granule cells produce NO and the synaptic terminals contacted with them were thought to be the target of NO. NO induces the release of glutamate, and it has been suggested that cGMP-dependent protein kinase may be involved in the alteration of synaptic vesicle dynamics [130,131].
Mitrukhina et al. reported that NaHS increased the frequency of miniature end-plate potentials and the amplitude of the evoked postsynaptic responses to a single stimulation in the motor nerve ending of the mouse diaphragm, suggesting the enhanced synaptic vesicle exocytosis and reduced endocytosis [132]. The same group showed that a similar observation was obtained in the neuromuscular junction showing the involvement of intracellular Ca2+, cAMP, and presynaptic ryanodine receptors in the vesicular release of neurotransmitters [133].
We recently found that H2S and H2S2 induce the release of neurotransmitters, GABA, glutamate, glycine, and that of neuromodulators, D-serine, L-serine, and glutamine using in vivo microdialysis (Figure 7) [41]. GABA and glutamate were greatly released by H2S and to a lesser extent by H2S2, while D-serine, L-serine, and glutamine were released less efficiently than GABA and glutamate, probably because their release mechanisms may be different. Considering the observations that H2S more greatly induced the release of GABA and glutamate than H2S2 and that the endogenous levels of H2S are greater than those of H2S2, H2S rather than H2S2 may mainly regulate the release of neurotransmitters [41]. In the in vivo microdialysis, the applied concentrations of Na2S and Na2S2 are dramatically decreased when they are released from the dialysis filter probe to the brain. The in vitro recovery from microdialysis probes has been reported between 0.1% and 7.6%, depending on molecules [134], and our study showed that Na2S was recovered approximately 0.2–1% and Na2S2 0.8–4.8% [41]. Based on these observations, a concentration of Na2S and Na2S2 a minimum of 50 times higher (1 mM) than that used for the brain cell suspension (20 μM) was applied.
The release of D-serine by H2S2 from the hippocampus of TRPA1 knockout rats showed no significant difference with that in the wild-type rats [41]. However, LTP was not induced in TRPA1 knockout rats, which agrees with the observation by Shigetomi et al. [127]. The synaptic transmission is regulated by the interaction between neurons and astrocytes, and astrocytes-dependent facilitation regulates the vesicular release of neurotransmitters including glutamate in the hippocampal synapses (Figure 8) [135]. These observations suggest that the activation of TRPA1 channels in astrocytes is required for the induction of LTP, but that the channels are not involved in the release of D-serine [41].
In the brain cell suspension, serotonin suppressed the release of H2S, while it increased that of H2S3 [41]. Acetylcholine increased the intracellular levels of H2S and the release of cysteine persulfide, and norepinephrine and GABA increased the release of cysteine persulfide [41]. These observations suggest that H2S and H2S2 facilitate the release of neurotransmitters, while neurotransmitters in turn regulate the release of H2S and H2S2. Probably due to the low recovery of H2S and H2S2 through the probe of in vivo microdialysis, the release of both molecules induced by the neurotransmitters was not detected [41].
Since the discovery of H2Sn activating TRPA1 channels, PTEN, and protein kinase G1α, the effects of H2S previously found were thought to be mediated by H2Sn [11,100,101]. However, H2S releases neurotransmitters more efficiently than H2S2 as described above. Moreover, H2S and H2S2 exert with a similar potency the neuroprotective effects against oxidative stress by increasing the intracellular concentrations of glutathione, the major endogenous antioxidant, through the activation of cystine/glutamate antiporter and cysteine transporter [136]. Alanine-serine-cysteine transporter (Asc-1), a neutral amino acid transporter located in the neurons, and Slc38a1 localized to GABAergic neurons in the hippocampus are candidate molecules releasing D-serine, L-serine, and glutamine [137,138,139]. These transporters may also be involved in the regulation of the release of GABA, glutamate, and glycine induced by H2S and H2S2.
The cytoprotective effect of H2S has been observed in other organs. H2S protects cardiac muscle by preserving the function of mitochondria [140], and mitochondrial H2S produced by 3MST regulates the catabolism of branched-chain amino acid to protect cardiac muscle from heart failure [141]. H2S-based therapy has the potential to attenuate the progression of Duchenne muscular dystrophy and other muscle-related diseases [142,143,144,145].

10. TRPA1 Channels Are Involved in Sulfur Metabolism

TRP channels are not only the target of H2Sn, but their regulation on sulfur metabolism and the levels of neurotransmitters have recently been reported (Figure 9). TRPA1-suppressed (homozygotes)-Drosophila showed decreased levels of methionine and cysteine, 15 and 50%, respectively, of the wild type [40]. The application of resiniferatoxin, an ultrapotent capsaicin analogue antagonist of TRP vanilloid type 1 (TRPV1) and TRPA1 channels [42,146], to porcine urinary bladder increased the transcription of rhodanese, and decreased that of sulfur dioxygenase (ETHE1) and molybdenum cofactor synthesis 2, which are involved in the metabolism of sulfur [42].
We found that the levels of 3MST and those of cysteine were lower in TRPA1 knockout rats compared to those in the wild type, while those of rhodanese (TST) were not changed [41]. The endogenous levels of H2S, H2S2, and cysteine persulfide in the brain of TRPA1-KO rats are also lower than those in the wild type, probably due to the low levels of both 3MST and cysteine, which is a substrate of CAT to produce 3MP [41].
TRPA1 channels also may regulate the levels of neurotransmitters. Deficiency of TRPA1 channels decreases the levels of glycine, while increases those of GABA [40,41]. The application of resiniferatoxin upregulates spermidine/spermine N(1)-acetyltransferase 2 (SAT2), which regulate the uptake of glutamate at the synaptic terminal, while suppresses the regulator of G protein signalling 7 (RGS7), which regulates synaptic plasticity and GABA signalling [42]. These observations suggest that TRPA1 channels not only respond to H2Sn, but also regulate the production of H2S/H2S2 and the neurotransmission by glutamate and GABA.
The activation of TRPA1 channels induces Ca2+ influx to increase the intracellular concentrations of Ca2+ that suppresses the activity of CAT [143]. In the absence of increase in the intracellular Ca2+ though TRPA1 channels, CAT may uncontrollably metabolize cysteine to produce excess 3MP [40,143], which may induce feedback inhibition on the production and transport of cysteine. It may cause a decrease in the transport of cysteine from astrocytes to neurons. The transcription or translation of sulfur-metabolizing enzymes including 3MST may also be regulated by TRPA1 channels [41,42]. Further studies are awaited to understand this mechanism.

11. Pathophysiological Roles of H2S and H2Sn

High concentrations of H2S are toxic, while low concentrations have benefits. Down’s syndrome (DS), characterized by impaired brain growth and maturation that causes mental retardation, has a trisomy of chromosome 21 where CBS is encoded. CBS in the brains of patients is approximately three times more abundant compared to that of normal individuals [147]. The urine of patients contains high levels of thiosulfate, a metabolite of H2S [148]. The overexpression of CBS showed DS like neurocognitive deficit in mice [149]. Fibroblasts prepared from DS patients showed suppression in the mitochondrial electron transport, oxygen consumption, and ATP generation [150].
Ethylmalonyl encephalopathy is an autosomal recessive early onset and defective in cytochrome c oxidase in the brain and muscle. In this disease, sulfur dioxygenase is deficient, resulting in increasing H2S levels that suppress cytochrome c oxidase [151].
Both excess and deficiency of H2S and H2Sn have been proposed to be involved in the pathogenesis of schizophrenia. Plasma H2S levels, which have a correlation with working memory and executive function, are significantly lower in patients than those of normal individuals [152]. Thiol homeostasis is shifted to more oxidized disulfide bond formation from free thiol in patients [153]. In contrast, it has been reported that a mouse model of schizophrenia showed greater levels of bound sulfur than a control. The levels of CBS, CSE, and 3MST in post-mortem brain of schizophrenia patients are significantly greater than those of normal individuals [154].
Hypersensitivity to NMDA receptor antagonists including MK-801 resembles positive symptoms in schizophrenia [155]. Although MK-801 induced hyperlocomotion even in the wild-type rats, a significant increase was observed in the locomotor activity after MK-801 administration in 3MST-KO rats compared to the wild-type rats [41]. Working memory examined with Y-maze showed that the total arm entry of 3MST-KO was significantly less than that of the wild type, but the percent spontaneous alternation was not significantly different between 3MST-KO and the wild-type rats. The other behavioural tests, the open field, PPI, and contextual fear conditioning tests did not show any significant difference between the genotypes in the rat model. The difference in PPI between mice and rats models may be involved, probably due to the increase in the levels of rhodanese in mice, while no changes in rats [41,156].
Gliomas with the highest grades of malignancy contained the greater levels of polysulfides than glioma-free brain regions [157]. A similar observation has been reported that H2Sn levels were greater in glioblastoma-bearing regions than glioblastoma-free control regions [158]. In contrast, CBS-silenced glioma increased the levels of VEGF and HIF-2α, deeply invaded with dense vascularization, and aggressively proliferated [159]. Further studies are awaited to clarify the involvement of H2S and its producing enzymes in cancer pathology.

12. Perspective

Since the identification of H2Sn regulating the activity of TRPA1 channels, PTEN, and protein kinase G1α [11,100,101], the effects of H2S previously reported had been thought to be mediated by H2Sn. However, there appeared cases in which H2S showed greater effects than H2Sn. H2S 10 times more potently induced the release of GABA than H2S2 in in vivo microdialysis from the hippocampus [41]. Another example is that H2S and H2Sn exerted the cytoprotective effect in a similar fashion on neurons against oxidative stress induced by high concentrations of glutamate [136]. Considering the fact that the endogenous levels of H2S are greater than those of H2Sn, H2S is responsible for these effects [41]. In these cases, the oxidized cysteine residues of the target proteins are S-sulfurated by H2S to generate P-SSH, and even reduced further, probably together with GSH to P-SH. Either H2S or H2Sn transmit signals depending on the form of the target cysteine residues.
The existence of the cysteine residues with sulfur atoms with different oxidation states in proteins has been predicted from the release and absorption of H2S from bound sulfane sulfur in tissues. The liver contains more bound sulfane sulfur than the brain. Although the heart has a little capacity to release H2S by DTT, it absorbed exogenously applied H2S as greatly as the liver, and more effectively than the brain, as described previously [43]. The species and amount of bound sulfane sulfur are different between tissues. It is possible that P-SOH and P-SNO, which do not release H2S under reducing condition but efficiently absorb H2S, are more abundant in the heart than the other tissues. The balance of cysteine residues with thiols or oxidized forms may cause differences in the transduction of signalling by H2S or H2Sn.
In addition to SAM, NO, CO, and Ca2+, which regulate the activity of H2S- and H2Sn- producing enzymes [5,50,56,61,143,160], neurotransmitters such as serotonin, acetylcholine, norepinephrine, and GABA regulate the release of H2S, H2Sn, and cysteine persulfide [48]. The regulation mechanism of H2S/H2Sn production by neurotransmitters, probably by the control of their producing enzymes, are yet to be clarified. The development of fluorescence probes, which are sensitive enough to detect the physiological concentrations of H2S, H2Sn, and other S-sulfurated molecules in real time, will clarify the involvement of H2S and H2Sn in regulating neurotransmission in the brain.
Polysulfides including H2S2 are reactive and unstable, but they still endogenously exist [39,41,43,48,86]. The total redox activity of H2S2, Cys-SSH, GSSH, and P-SSH is well balanced with that of H2S, Cys-SH, GSH, and P-SH in the steady state in cells. It may locally be unbalanced when S-sulfurated molecules are produced, but once signalling has been performed, it returns to the steady state by reacting with the surrounding molecules such as GSH to normalize the redox state. The regulation of the total redox balance may be another problem to be clarified.
The involvement of TRPA1 channels in the metabolism of sulfur-containing molecules and the translation or transcription of sulfur-metabolizing enzymes will open a new field in the function of TRP channels together with that of H2S and polysulfides.

Funding

This work was supported by Grants-in-Aid for Scientific Research from the Ministry of Education, Sciences, Sports, and Technology, Japan (23K06016), by Terumo Life Science Foundation and by Smoking Research Foundation. I also thank the Sanyo-Onoda City university for the support.

Acknowledgments

I thank Yuka Kimura for preparing the manuscript.

Conflicts of Interest

The author declares no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

References

  1. Warenycia, M.W.; Goodwin, L.R.; Benishin, C.G.; Reiffenstein, R.J.; Grancom, D.M.; Taylor, J.D.; Dieken, F.P. Acute hydrogen sulfide poisoning. Demonstration of selective uptake of sulfide by the brainstem by measurement of brain sulfide levels. Biochem. Pharmacol. 1989, 38, 973–981. [Google Scholar] [CrossRef] [PubMed]
  2. Hannah, R.S.; Hayden, L.J.; Roth, S.H. Hydrogen sulfide exposure alters the amino acid content in developing rat CNS. Neurosci. Lett. 1989, 99, 323–327. [Google Scholar] [CrossRef]
  3. Warenycia, M.W.; Goodwin, L.R.; Francom, D.M.; Dieken, F.P.; Kombian, S.B.; Reiffenstein, R.J. Dithiothreitol liberates non-acid labile sulfide from brain tissue of H2S-poisoned animals. Arch. Toxicol. 1990, 64, 650–655. [Google Scholar] [CrossRef] [PubMed]
  4. Stipanuk, M.H.; Beck, P.W. Characterization of the enzymic capacity for cysteine desulphhydration in liver and kidney of the rat. Biochem. J. 1982, 206, 267–277. [Google Scholar] [CrossRef] [PubMed]
  5. Abe, K.; Kimura, H. The possible role of hydrogen sulfide as an endogenous neuromodulator. J. Neurosci. 1996, 16, 1066–1071. [Google Scholar] [CrossRef] [PubMed]
  6. Hosoki, R.; Matsuki, N.; Kimura, H. The possible role of hydrogen sulfide as an endogenous smooth muscle relaxant in synergy with nitric oxide. Biochem. Biophys. Res. Commun. 1997, 237, 527–531. [Google Scholar] [CrossRef] [PubMed]
  7. Ishii, I.; Akahoshi, N.; Yu, X.-N.; Kobayashi, Y.; Namekata, K.; Komaki, G.; Kimura, H. Murine cystathionine γ-lyase: Complete cDNA and genomic sequences, promoter activity, tissue distribution and developmental expression. Biochem. J. 2004, 381, 113–123. [Google Scholar] [CrossRef] [PubMed]
  8. Giovinazzo, D.; Bursac, B.; Sbodio, J.I.; Nalluru, S.; Vignane, T.; Snowman, A.M.; Albacarys, L.M.; Sedlak, T.W.; Torregrossa, R.; Whiteman, M.; et al. Hydrogen sulfide is neuroprotective in Alzheimer’s disease by sulfhydrating GSK3β and inhibiting Tau hyperphosphorylation. Proc. Natl. Acad. Sci. USA 2021, 118, e2017225118. [Google Scholar] [CrossRef]
  9. Paul, B.D.; Sbodio, J.I.; Xu, R.; Vandiver, M.S.; Cha, J.Y.; Snowman, A.M.; Snyder, S.H. Cystathionine γ-lyase deficiency mediates neurodegeneration in Huntington’s disease. Nature 2014, 509, 96–100. [Google Scholar] [CrossRef]
  10. Shibuya, N.; Tanaka, M.; Yoshida, M.; Ogasawara, Y.; Togawa, T.; Ishii, K.; Kimura, H. 3-Mercaptopyruvate sulfurtransferease produces hydrogen sulfide and bound sulfane sulfur in the brain. Antioxid. Redox Signal. 2009, 11, 703–714. [Google Scholar] [CrossRef]
  11. Kimura, Y.; Mikami, Y.; Osumi, K.; Tsugane, M.; Oka, J.-I.; Kimura, H. Polysulfides are possible H2S-derived signaling molecules in rat brain. FASEB J. 2013, 27, 2451–2457. [Google Scholar] [CrossRef] [PubMed]
  12. Kimura, Y.; Toyofuku, Y.; Koike, S.; Shibuya, N.; Nagahara, N.; Lefer, D.; Kimura, H. Identification of H2S3 and H2S produced by 3mercaptopyruvate sulfurtransferase in the brain. Sci. Rep. 2015, 5, 14774. [Google Scholar] [CrossRef] [PubMed]
  13. Shibuya, N.; Koike, S.; Tanaka, M.; Ishigami-Yuasa, M.; Kimura, Y.; Ogasawara, Y.; Fukui, K.; Nagahara, N.; Kimura, H. A novel pathway for the production of hydrogen sulfide from D-cysteine in mammalian cells. Nat. Commun. 2013, 4, 1366. [Google Scholar] [CrossRef] [PubMed]
  14. Semenza, E.R.; Harraz, M.M.; Abramson, E.; Malla, A.P.; Vasavda, C.; Gadalla, M.M.; Kornberg, M.D.; Snyder, S.H.; Roychaudhuri, R. D-cysteine is an endogenous regulator of neural progenitor cell dynamics in the mammalian brain. Proc. Natl. Acad. Sci. USA 2021, 118, e2110610118. [Google Scholar] [CrossRef] [PubMed]
  15. Enokido, Y.; Suzuki, E.; Iwasawa, K.; Namekata, K.; Okazawa, H.; Kimura, H. Cystathionine beta-synthase, a key enzyme for homocysteine metabolism, is preferentially expressed in the radial glia/astrocyte lineage of developing mouse CNS. FASEB J. 2005, 19, 1854–1856. [Google Scholar] [CrossRef] [PubMed]
  16. Nagahara, N.; Ito, T.; Kitamura, H.; Nishino, T. Tissue and subcellular distribution of mercaptopyruvate sulfurtransferase in the rat: Confocal laser fluorescence and immunoelectron microscopic studies combined with biochemical analysis. Histochem. Cell Biol. 1998, 110, 243–250. [Google Scholar] [CrossRef] [PubMed]
  17. Landry, A.P.; Ballou, D.P.; Banerjee, R. H2S oxidation by nanodisc-embedded human sulfide quinone oxidoreductase. J. Biol. Chem. 2017, 292, 11641–11649. [Google Scholar] [CrossRef] [PubMed]
  18. Bostelaar, T.; Vitvitsky, V.; Kumutima, J.; Lewis, B.E.; Yadav, P.K.; Brunold, T.C.; Banerjee, R. Hydrogen sulfide oxidation by myoglobin. J. Am. Chem. Soc. 2016, 138, 8476–8488. [Google Scholar] [CrossRef]
  19. Ruetz, M.; Kumutima, J.; Lewis, B.E.; Filipovic, M.R.; Lehnert, N.; Stemmler, T.L.; Banerjee, R. A distal ligand mutes the interaction of hydrogen sulfide with human neuroglobin. J. Biol. Chem. 2017, 292, 6512–6528. [Google Scholar] [CrossRef]
  20. Olson, K.R.; Gao, Y.; DeLeon, E.R.; Arif, M.; Arif, F.; Arora, N.; Straub, K.D. Catalase as a sulfide–sulfur oxido-reductase: An ancient (and modern?) regulator of reactive sulfur species (RSS). Redox Biol. 2017, 12, 325–339. [Google Scholar] [CrossRef]
  21. Searcy, D.G.; Whitehead, J.P.; Maroney, M.J. Interaction of Cu, Zn superoxide dismutase with hydrogen sulfide. Arch. Biochem. Biophys. 1995, 318, 251–263. [Google Scholar] [CrossRef] [PubMed]
  22. Garai, D.; Ríos-González, B.B.; Furtmüller, P.G.; Fukuto, J.M.; Xian, M.; López-Garriga, J.; Nagy, P. Mechanisms of myeloperoxidase catalyzed oxidation of H2S by H2O2 or O2 to produce potent protein Cys–polysulfide-inducing species. Free Radic. Biol. Med. 2017, 113, 551–563. [Google Scholar] [CrossRef] [PubMed]
  23. Akaike, T.; Ida, T.; Wei, F.-Y.; Nishida, M.; Kumagai, Y.; Alam, M.M.; Motohashi, H. Cysteinyl-tRNA synthetase governs cysteine polysulfidation and mitochondrial bioenergetics. Nat. Commun. 2017, 8, 1177. [Google Scholar] [CrossRef] [PubMed]
  24. Zhao, W.; Zhang, J.; Lu, Y.; Wang, R. The vasorelaxant effect of H2S as a novel endogenous gaseous KATP channel opener. EMBO J. 2001, 20, 6008–6016. [Google Scholar] [CrossRef] [PubMed]
  25. Whiteman, M.; Li, L.; Kostetski, I.; Chu, S.H.; Siau, J.L.; Bhatia, M.; Moore, P.K. Evidence for the formation of a novel nitrosothiol from the gaseous mediators nitric oxide and hydrogen sulphide. Biochem. Biophys. Res. Commun. 2006, 343, 303–310. [Google Scholar] [CrossRef] [PubMed]
  26. Ondrias, K.; Stasko, A.; Cacanyiova, S.; Sulova, Z.; Krizanova, O.; Kristek, F.; Malekova, L.; Knezl, V.; Breier, A. H2S and HS− donor NaHS releases nitric oxide from nitrosothiols, metal nitrosyl complex, brain homogenate and murine L1210 leukaemia cells. Pflug. Arch. Eur. J. Physiol. 2008, 457, 271–279. [Google Scholar] [CrossRef]
  27. Kondo, K.; Bhushan, S.; King, A.L.; Prabhu, S.D.; Hamid, T.; Koenig, S.; Murohara, T.; Predmore, B.L.; Gojon, G.S.; Gojon, G.J.; et al. H2S protects against pressure overload-induced heart failure via upregulation of endothelial nitric oxide synthase. Circulation 2013, 127, 1116–1127. [Google Scholar] [CrossRef]
  28. King, A.L.; Polhemus, D.; Bhushan, S.; Otsuka, H.; Kondo, K.; Nicholson, C.K.; Bradley, J.M.; Islam, K.N.; Calvert, J.W.; Tao, Y.-X.; et al. Hydrogen sulfide cytoprotective signaling is endothelial nitric oxide synthase-nitric oxide dependent. Proc. Natl. Acad. Sci. USA 2014, 111, 3182–3187. [Google Scholar] [CrossRef]
  29. Eberhardt, M.; Dux, M.; Namer, B.; Jiljkovic, J.; Cordasic, N.; Will, C.; Filipovic, M.R. H2S and NO cooperatively regulate vascular tone by activating a neuroendocrine HNO–TRPA1–CGRP signaling pathway. Nat. Commun. 2014, 5, 4381. [Google Scholar] [CrossRef]
  30. Cortese-Krott, M.M.; Kuhnle, G.G.C.; Dyson, A.; Fernandez, B.O.; Grman, M.; DuMond, J.F.; Feelisch, M. Key bioactive reaction products of the NO/H2S interaction are S/N-hybrid species, polysulfides, and nitroxyl. Proc. Natl. Acad. Sci. USA 2015, 112, E4651–E4660. [Google Scholar] [CrossRef]
  31. Moustafa, A.; Habara, Y. Cross talk between polysulfide and nitric oxide in rat peritoneal mast cells. Am. J. Physiol. Cell Physiol. 2016, 310, C894–C902. [Google Scholar] [CrossRef] [PubMed]
  32. Miyamoto, R.; Koike, S.; Takano, Y.; Shibuya, N.; Kimura, Y.; Hanaoka, K.; Kimura, H. Polysulfides (H2Sn) produced from the interaction of hydrogen sulfide (H2S) and nitric oxide (NO) activate TRPA1 channels. Sci. Rep. 2017, 7, 45995. [Google Scholar] [CrossRef] [PubMed]
  33. Hildebrandt, T.M.; Meo, I.D.; Zeviani, M.; Viscomi, C.; Braun, H.P. Proteome Adaptations in Ethe1-deficient Mice Indicate a Role in Lipid Catabolism and Cytoskeleton Organization via Post-Translational Protein Modifications. Biosci. Rep. 2013, 33, e00052. [Google Scholar] [CrossRef] [PubMed]
  34. Aizenman, E.; Lipton, D.A.; Loring, R.H. Selective modulation of NMDA responses by reduction and oxidation. Neuron 1989, 2, 1257–1263. [Google Scholar] [CrossRef] [PubMed]
  35. Kimura, H. Hydrogen polysulfide (H2Sn) signaling along with hydrogen sulfide (H2S) and nitric oxide (NO). J. Neural Transm. 2016, 123, 1235–1245. [Google Scholar] [CrossRef] [PubMed]
  36. Kato, A.; Ogura, M.; Suda, M. Control mechanism in the rat liver enzyme system converting L-methionine to L-cystine. 3. Noncompetitive inhibition of cystathionine synthetase-serine dehydratase by elemental sulfur and competitive inhibition of cystathionase-homoserine dehydratase by L-cysteine and L-cystine. J. Biochem. 1966, 59, 40–48. [Google Scholar] [PubMed]
  37. Branzoli, U.; Massey, V. Preparation of aldehyde oxidase in its native and deflavo forms. Comparison of spectroscopic and catalytic properties. J. Biol. Chem. 1974, 249, 4339–4345. [Google Scholar] [CrossRef]
  38. Conner, J.; Russell, P.J. Elemental sulfur: A novel inhibitor of adenylate kinase. Biochem. Biophys. Res. Commun. 1983, 113, 348–352. [Google Scholar] [CrossRef]
  39. Mustafa, A.K.; Gadalla, M.M.; Sen, N.; Kim, S.; Mu, W.; Gazi, S.K.; Barrow, R.K.; Yang, G.; Wang, R.; Snyder, S.H. H2S signals through protein S-sulfhydration. Sci. Signal. 2009, 2, ra72. [Google Scholar] [CrossRef]
  40. Lee, J.E.; Kim, Y.; Kim, K.H.; Lee, D.Y.; Lee, Y. Contribution of Drosophila TRPA1 to Metabolism. PLoS ONE 2016, 11, e0152935. [Google Scholar] [CrossRef]
  41. Furuie, H.; Kimura, Y.; Akaishi, T.; Yamada, M.; Miyasaka, Y.; Saitoh, A.; Shibuya, N.; Watanabe, A.; Kusunose, N.; Mashimo, T.; et al. Hydrogen sulfide and polysulfides induce GABA/glutamate/D-serine release, facilitate hippocampal LTP, and regulate behavioral hyperactivity. Sci. Rep. 2023, 13, 17663. [Google Scholar] [CrossRef] [PubMed]
  42. Lepiarczyk, E.; Paukszto, Ł.; Wiszpolska, M.; Łopieńska-Biernat, E.; Bossowska, A.; Majewski, M.K.; Majewska, M. Molecular Influence of Resiniferatoxin on the Urinary Bladder Wall Based on Differential Gene Expression Profiling. Cells 2023, 12, 462. [Google Scholar] [CrossRef] [PubMed]
  43. Ishigami, M.; Hiraki, K.; Umemura, K.; Ogasawara, Y.; Ishii, K.; Kimura, H. A source of hydrogen sulfide and a mechanism of its release in the brain. Antioxid. Redox Signal. 2009, 11, 205–214. [Google Scholar] [CrossRef] [PubMed]
  44. Goodwin, L.R.; Francom, D.; Dieken, F.P.; Taylor, J.D.; Warenycia, M.W.; Reiffenstein, R.J.; Dowling, G. Determination of sulfide in brain tissue by gas dialysis/ion chromatography: Postmortem studies and two case reports. J. Anal. Toxicol. 1989, 13, 105–109. [Google Scholar] [CrossRef] [PubMed]
  45. Savage, J.C.; Gould, D.H. Determination of sulfide in brain tissue and rumen fluid by ion-interaction reversed-phase high-performance liquid chromatography. J. Chromatogr. 1990, 526, 540–545. [Google Scholar] [CrossRef] [PubMed]
  46. Furne, J.; Saeed, A.; Levitt, M.D. Whole tissue hydrogen sulfide concentrations are orders of magnitude lower than presently accepted values. Am. J. Physiol. Regul. Integr. Comp. Physiol. 2008, 295, R1479–R1498. [Google Scholar] [CrossRef] [PubMed]
  47. Nagy, P.; Pálinkás, Z.; Nagy, A.; Budai, B.; Tóth, I.; Vasas, A. Chemical aspects of hydrogen sulfide measurements in physiological samples. Biochim. Biophys. Acta. 2014, 1840, 876–891. [Google Scholar] [CrossRef] [PubMed]
  48. Koike, S.; Kawamura, K.; Kimura, Y.; Shibuya, N.; Kiimura, H.; Ogasawara, Y. Analysis of endogenous H2S and H2Sn in mouse brain by high performance liquid chromatography with fluorescence and tandem mass spectrometric detection. Free Radic. Biol. Med. 2017, 113, 355–362. [Google Scholar] [CrossRef]
  49. Shan, X.; Dunbrack, R.L.J.; Christopher, S.A.; Kruger, W.D. Mutation in the regulatory domain of cystathionine β–synthase can functionally suppress patient-derived mutations in cis. Hum. Mol. Genet. 2001, 10, 635–643. [Google Scholar] [CrossRef]
  50. Taoka, S.; Banerjee, R. Characterization of NO binding to human cystathionine beta-synthase: Possible implications of the effects of CO and NO binding to the human enzyme. J. Inorg. Biochem. 2001, 87, 245–251. [Google Scholar] [CrossRef]
  51. Niu, W.-N.; Yadav, P.K.; Adamec, J.; Banerjee, R. S-Glutathionylation enhances human cystathionine β–synthase activity under oxidative stress conditions. Antioxid. Redox Signal. 2015, 22, 350–361. [Google Scholar] [CrossRef]
  52. Morikawa, T.; Kajimura, M.; Nakamura, T.; Hishiki, T.; Nakanishi, T.; Yukutake, Y.; Nagahata, Y.; Ishikawa, M.; Hattori, K.; Takenouchi, T.; et al. Hypoxic regulation of the cerebral microcirculation is mediated by a carbon monoxide-sensitive hydrogen sulfide pathway. Proc. Natl. Acad. Sci. USA. 2012, 109, 1293–1298. [Google Scholar] [CrossRef] [PubMed]
  53. Marutani, E.; Morita, M.; Hirai, S.; Kai, S.; Grange, R.M.H.; Miyazaki, Y.; Nagashima, F.; Traeger, L.; Magliocca, A.; Ida, T.; et al. Sulfide catabolism ameliorates hypoxic brain injury. Nat. Commun. 2021, 12, 3108. [Google Scholar] [CrossRef] [PubMed]
  54. Linden, D.R.; Furne, J.; Stoltz, G.J.; Abdel-Rehim, M.S.; Levitt, M.D.; Szurszewski, J.H. Sulphide quinone reductase contributes to hydrogen sulphide metabolism in murine peripheral tissues but not in the CNS. Br. J. Pharm. 2012, 165, 2178–2190. [Google Scholar] [CrossRef] [PubMed]
  55. Robert, K.; Vialard, F.; Thiery, E.; Toyama, K.; Sinet, P.M.; Janel, N.; London, J. Expression of the cystathionine beta synthase (CBS) gene during mouse development and immunolocalization in adult brain. J. Histochem. Cytochem. 2003, 51, 363–371. [Google Scholar] [CrossRef] [PubMed]
  56. Mikami, Y.; Shibuya, N.; Ogasawara, Y.; Kimura, H. Hydrogen sulfide is produced by cystathionine γ–lyase at the steady-state low intracellular Ca2+ concentrations. Biochem. Biophys. Res. Commun. 2013, 431, 131–135. [Google Scholar] [CrossRef] [PubMed]
  57. Sen, N.; Paul, B.D.; Gadalla, M.M.; Mustafa, A.K.; Sen, T.; Xu, R.; Kim, S.; Snyder, S.H. Hydroen sulfide-linked sulfhydration of NF-κB mediates its intiapoptotic actions. Mol. Cell. 2012, 45, 13–24. [Google Scholar] [CrossRef] [PubMed]
  58. Meister, A.; Fraser, P.E.; Tice, S.V. Enzymatic desulfuration of β-mercaptopyruvate to pyruvate. J. Biol. Chem. 1954, 206, 561–575. [Google Scholar] [CrossRef]
  59. Taniguchi, T.; Kimura, T. Role of 3-mercaptopyruvate sulfurtransferase in the formation of the iron-sulfur chromophore of adrenal ferredoxin. Biochim. Biophys. Acta 1974, 364, 284–295. [Google Scholar] [CrossRef]
  60. Ubuka, T.; Umemura, S.; Yuasa, S.; Kinuta MWatanabe, K. Purification and characterization of mitochondrial cysteine aminotransferase from rat liver. Physiol. Chem. Phys. 1978, 10, 483–500. [Google Scholar]
  61. Mikami, Y.; Shibuya, N.; Kimura, Y.; Nagahara, N.; Ogasawara, Y.; Kimura, H. Thioredoxin and dihydrolipoic acid are required for 3-mercaptopyruvate sulfurtransferase to produce hydrogen sulfide. Biochem. J. 2011, 439, 479–485. [Google Scholar] [CrossRef]
  62. Yadav, P.K.; Yamada, K.; Chiku, T.; Koutmos, M.; Banerjee, R. Structure and kinetic analysis of H2S production by human mercaptopyruvate sulfurtransferase. J. Biol. Chem. 2013, 288, 20002–20013. [Google Scholar] [CrossRef]
  63. Griffith, O.W. Biologic and pharmacologic regulation of mammalian glutathione synthesis. Free Radic. Biol. Med. 1999, 27, 922–935. [Google Scholar] [CrossRef]
  64. Tateishi, N.; Higashi, T.; Naruse, A.; Nakashima, K.; Shiozaki, H. Rat liver glutathione: Possible role as a reservoir of cysteine. J. Nutr. 1977, 107, 51–60. [Google Scholar] [CrossRef] [PubMed]
  65. Schumann, U.; Subramani, S. Special delivery from mitochondria to peroxisomes. Trends Cell Biol. 2008, 18, 253–256. [Google Scholar] [CrossRef] [PubMed]
  66. Rfeffer, M.; Ressler, C. p-Cy anoalanine, an inhibitor of rat liver cystathionase. Biochem. Pharmacol. 1967, 16, 2299–2308. [Google Scholar]
  67. Uren JRRaain RChavkovskv, M. Modulation of cvsteine metabolism in mice—Effecis of propargylglycine and L-cyst(e)ine-degrading enzymes. Biochem. Pharmacol. 1978, 27, 2807–2814. [Google Scholar]
  68. Braunstein, A.E.; Goryachenkowa, E.V.; Tolosa, E.A.; Willhardt, I.H.; Yefremova, L.L. Specificity and some other properties of liver serine sulphhydrase: Evidence for its identity with cystathionine β-synthase. Biochim. Biophys. Acta 1971, 242, 247–260. [Google Scholar] [CrossRef] [PubMed]
  69. Hanaoka, K.; Sasakura, K.; Suwanai, Y.; Toma-Fukai, S.; Shimamoto, K.; Takano, Y.; Shibuya, N.; Terai, T.; Komatsu, T.; Ueno, T.; et al. Discovery and Mechanistic Characterization of Selective Inhibitors of H2S-producing Enzyme: 3-Mercaptopyruvate Sulfurtransferase (3MST) Targeting Active-site Cysteine Persulfide. Sci. Rep. 2017, 7, 40227. [Google Scholar] [CrossRef] [PubMed]
  70. Ogasawara, Y.; Ishii, K.; Togawa, T.; Tanabe, S. Determination of bound sulfur in serum by gas dialysis/high-performance liquid chromatography. Anal. Biochem. 1993, 215, 73–81. [Google Scholar] [CrossRef]
  71. Kimura, Y.; Koike, S.; Shibuya, N.; Lefer, D.; Ogasawara, Y.; Kimura, H. 3-Mercaptopyruvate sulfurtransferase produces potential redox regularots cysteine- and glutathione-persulfide (Cys-SSH and GSSH) together with signaling molecules H2S2, H2S3 and H2S. Sci. Rep. 2017, 7, 10459. [Google Scholar] [CrossRef]
  72. Pedre, B.; Talwar, D.; Barayeu, U.; Schilling, D.; Luzarowski, M.; Sokolowski, M.; Glatt, S.; Dick, T.P. 3-Mercaptopyruvate sulfur transferase is a protein persulfidase. Nat. Chem. Biol. 2023, 19, 507–517. [Google Scholar] [CrossRef]
  73. Kimura, H. Signalling by hydrogen sulfide and polysulfides via protein S-sulfuration. Br. J. Pharmacol. 2020, 177, 720–733. [Google Scholar] [CrossRef] [PubMed]
  74. Lancaster, J.R., Jr. How are nitrosothiols formed de novo in vivo? Arch. Biochem. Biophys. 2017, 617, 137–144. [Google Scholar] [CrossRef] [PubMed]
  75. Seth, D.; Hess, D.T.; Hausladen, A.; Wang, L.; Wang, Y.J.; Stamler, J.S. A Multiplex Enzymatic Machinery for Cellular Protein S-nitrosylation. Mol. Cell. 2018, 69, 451–464.e6. [Google Scholar] [CrossRef] [PubMed]
  76. Nagahara, N.; Okazaki, T.; Nishino, T. Cytosolic mercaptopyruvate sulfurtransferase is evolutionarily related to mitochondrial rhodanese. Striking similarity in active site amino acid sequence and the increase in the mercaptopyruvate sulfurtransferase activity of rhodanese by site-directed mutagenesis. J. Biol. Chem. 1995, 270, 16230–16235. [Google Scholar] [PubMed]
  77. Frasdorf, B.; Radon, C.; Leimkuhler, S. Characterization and interaction studies of two isoforms of the dual localized 3-mercaptopyruvate sulfurtransferase TUM1 from humans. J. Biol. Chem. 2014, 289, 34543–34556. [Google Scholar] [CrossRef] [PubMed]
  78. Wong, T.W.; Harris, M.A.; Jankowicz, C.A. Transfer ribonucleic acid sulfurtransferase isolated from rat cerebral hemispheres. Biochemistry 1974, 13, 2805–2812. [Google Scholar] [CrossRef] [PubMed]
  79. Wong, T.W.; Harris, M.A.; Morris, H.P. The presence of an inhibitor of RNA sulfurtransferase in Morris hepatomas. Biochem. Biophys. Res. Commun. 1975, 65, 1137–1145. [Google Scholar] [CrossRef]
  80. Kimura, H. Metabolic turnover of hydrogen sulfide. Front. Physiol. 2012, 3, 101. [Google Scholar] [CrossRef]
  81. Vitvitsky, V.; Kabil, O.; Banerjee, R. High turnover rates for hydrogen sulfide allow for rapid regulation of its tissue concentrations. Antioxid. Redox Signal. 2012, 17, 22–31. [Google Scholar] [CrossRef]
  82. Searcy, D.G. HS−: O2 oxidoreductase activity of Cu, Zn superoxide dismutase. Arch. Biochem. Biophys. 1996, 334, 50–58. [Google Scholar] [CrossRef]
  83. Olson, K.R.; Gao, Y.; Arif, F.; Arora, K.; Patel, S.; DeLeon, E.R.; Straub, K.D. Metabolism of hydrogen sulfide (H2S) and production of reactive sulfur species (RSS) by superoxide dismutase. Redox Biol. 2018, 15, 74–85. [Google Scholar] [CrossRef] [PubMed]
  84. Nakamura, S.; Nakamura, M.; Yamazaki, I.; Morrison, M. Reactions of ferryl lactoperoxidase (compound II) with sulfide and sulfhydryl compounds. J. Biol. Chem. 1984, 259, 7080–7085. [Google Scholar] [CrossRef] [PubMed]
  85. Cavallini, D.; Marco, C.D.; Mondavi, B.; Mori, B.G. The cleavage of cystine by cystathionase and the transulfuration of hypotaurine. Enzymologia 1960, 22, 161–173. [Google Scholar] [PubMed]
  86. Ida, T.; Sawa, T.; Ihara, H.; Tsuchiya, Y.; Watanabe, Y.; Kumagai, Y.; Suematsu, M.; Motohashi, H.; Fujii, S.; Matsunaga, T.; et al. Reactive cysteine persulfides and S-polythiolation regulate oxidative stress and redox signaling. Proc. Natl. Acad. Sci. USA 2014, 111, 7606–7611. [Google Scholar] [CrossRef] [PubMed]
  87. Stipanuk, M.H. Metabolism of sulfur-containing amino acids. Ann. Rev. Nutr. 1986, 6, 179–209. [Google Scholar] [CrossRef]
  88. Yadav, P.K.; Martinov, M.; Vitvitsky, V.; Seravalli, J.; Wedmann, R.; Filipovic, M.R.; Banerjee, R. Biosynthesis and Reactivity of Cysteine Persulfides in Signaling. J. Am. Chem. Soc. 2016, 138, 289–299. [Google Scholar] [CrossRef]
  89. Zainol Abidin, Q.H.; Ida, T.; Morita, M.; Matsunaga, T.; Nishimura, A.; Jung, M.; Hassan, N.; Takata, T.; Ishii, I.; Kruger, W.; et al. Synthesis of Sulfides and Persulfides Is Not Impeded by Disruption of Three Canonical Enzymes in Sulfur Metabolism. Antioxidants 2023, 12, 868. [Google Scholar] [CrossRef]
  90. Teague, B.; Asiedu, S.; Moore, P.K. The smooth muscle relaxant effect of hydrogen sulphide in vitro: Evidence for a physiological role to control intestinal contractility. Br. J. Pharmacol. 2002, 137, 139–145. [Google Scholar] [CrossRef]
  91. Filipovic, M.R.; Miljkovic, J.L.j.; Nauser, T.; Royzen, M.; Klos, K.; Shubina, T.; Koppenol, W.H.; Lippard, S.J.; Ivanović-Burmazović, I. Chemical characterization of the smallest S-nitrosothiol, HSNO; cellular cross-talk of H2S and S-nitrosothiols. J. Am. Chem. Soc. 2012, 134, 12016–12027. [Google Scholar] [CrossRef]
  92. Li, L.; Salto-Tellez, M.; Tan, C.H.; Whiteman, M.; Moore, P.K. GYY4137, a novel hydrogen sulfide-releasing molecule, protects against endotoxic shock in the rat. Free Radic. Biol. Med. 2009, 47, 103–113. [Google Scholar] [CrossRef]
  93. Chen, W. New fluorescent probes for sulfane sulfurs and the application in bioimaging. Chem. Sci. 2013, 4, 2892–2896. [Google Scholar] [CrossRef] [PubMed]
  94. Bogdándi, V.; Ditrói, T.; Bátai, I.Z.; Sándor, Z.; Minnion, M.; Vasas, A.; Galambos, K.; Buglyó, P.; Pintér, E.; Feelisch, M.; et al. Nitrosopersulfide (SSNO−) Is a Unique Cysteine Polysulfidating Agent with Reduction-Resistant Bioactivity. Antioxid. Redox Signal. 2020, 33, 1277–1294. [Google Scholar] [CrossRef] [PubMed]
  95. Nagai, Y.; Tsugane, M.; J-IOka Kimura, H. Polysulfides induce calcium waves in rat hippocampal astrocytes. J. Pharmacol. Sci. 2006, 100, 200. [Google Scholar]
  96. Nagai, Y.; Tsugane, M.; Oka, J.; Kimura, H. Hydrogen sulfide induces calcium waves in astrocytes. FASEB J. 2004, 18, 557–559. [Google Scholar] [CrossRef] [PubMed]
  97. Streng, T.; Axelsson, H.E.; Hedlund, P.; Andersson, D.A.; Jordt, S.E.; Bevan, S.; Zygmunt, P.M. Distribution and function of the hydrogen sulfide-sensitive TRPA1 ion channel in rat urinary bladder. Eur. Urol. 2008, 53, 391–399. [Google Scholar] [CrossRef] [PubMed]
  98. Wang, L.; Cvetkov, T.L.; Chance, M.R.; Moiseenkova-Bell, V.Y. Identification of in vivo disulfide conformation of TRPA1 ion channel. J. Biol. Chem. 2012, 287, 6169–6176. [Google Scholar] [CrossRef] [PubMed]
  99. Hatakeyama, Y.; Takahashi, K.; Tominaga, M.; Kimura, H.; Ohta, T. Polysulfide evokes acute pain through the activation of nociceptive TRPA1 in mouse sensory neurons. Mol. Pain 2015, 11, 24. [Google Scholar] [CrossRef]
  100. Greiner, R.; Palinkas, Z.; Basell, K.; Becher, D.; Antelmann, H.; Nagy, P.; Dick, T.P. Polysulfides link H2S to protein thiol oxidation. Antioxid. Redox Signal. 2013, 19, 1749–1765. [Google Scholar] [CrossRef]
  101. Stubbert, D.; Prysyazhna, O.; Rudyk, O.; Scotcher, J.; Burgoyne, J.R.; Eaton, P. Protein kinase G Iα oxidation paradoxically underlies blood pressure lowering by the reductant hydrogen sulfide. Hypertension 2014, 64, 1344–1351. [Google Scholar] [CrossRef] [PubMed]
  102. Mustafa, A.K.; Sikka, G.; Gazi, S.K.; Steppan, J.; Jung, S.M.; Bhunia, A.K.; Barodka, V.M.; Gazi, F.K.; Barrow, R.K.; Wang, R.; et al. Hydrogen sulfide as endothelium-derived hyperpolarizing factor sulfhydrates potassium channels. Circ. Res. 2011, 109, 1259–1268. [Google Scholar] [CrossRef] [PubMed]
  103. Jarosz, A.P.; Wei, W.; Gauld, J.W.; Auld, J.; Ozcan, F.; Aslan, M.; Mutus, B. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is inactivated by S-sulfuration in vitro. Free Radic. Biol. Med. 2015, 89, 512–521. [Google Scholar] [CrossRef] [PubMed]
  104. Go, Y.M.; Jones, D.P. The redox proteome. J. Biol. Chem. 2013, 288, 26512–26520. [Google Scholar] [CrossRef] [PubMed]
  105. Ogasawara, Y.; Isoda, S.; Tanabe, S. Tissue and subcellular distribution of bound and acid-labile sulfur, and the enzymic capacity for sulfide production in the rat. Biol. Pharm. Bull. 1994, 17, 1535–1542. [Google Scholar] [CrossRef] [PubMed]
  106. Sun, Q.A.; Wang, B.; Miyagi, M.; Hess, D.T.; Stamler, J.S. Oxygen-coupled redox regulation of the skeletal muscle ryanodine receptor/Ca2+ release channel (RyR1): Sites and nature of oxidative modification. J. Biol. Chem. 2013, 288, 22961–22971. [Google Scholar] [CrossRef] [PubMed]
  107. Vandiver, M.S.; Paul, B.D.; Xu, R.; Karuppagounder, S.; Rao, F.; Snowman, A.M.; Ko, H.S.; Lee, Y.I.I.; Dawson, V.L.; Dawson, T.M.; et al. Sulfhydration mediates neuroprotective actions of parkin. Nat. Commun. 2013, 4, 1626. [Google Scholar] [CrossRef] [PubMed]
  108. Takahashi, N.; Kuwaki, T.; Kiyonaka, S.; Numata, T.; Kozai, D.; Mizuno, Y.; Yamamoto, S.; Naito, S.; Knevels, E.; Carmeliet, P.; et al. TRPA1 underlies a sensing mechanism for O2. Nat. Chem. Biol. 2011, 7, 701–711. [Google Scholar] [CrossRef]
  109. Takahashi, N.; Mizuno, Y.; Kozai, D.; Yamamoto, S.; Kiyonaka, S.; Shibata, T.; Uchida, K.; Mori, Y. Molecular characterization of TRPA1 channel activation by cysteine-reactive inflammatory mediators. Channels 2008, 2, 287–298. [Google Scholar] [CrossRef]
  110. D’Autreaux, B.; Toledano, M.B. ROS as signaling molecules: Mechanisms that generate specificity in ROS homeostasis. Nat. Rev. Mol. Cell Biol. 2007, 8, 813–824. [Google Scholar] [CrossRef]
  111. Carballal, S.; Trujillo, M.; Cuevasanta, E.; Bartesaghi, S.; Möller, M.N.; Folkes, L.K.; García-Bereguiaín, M.A.; Gutiérrez-Merino, C.; Wardman, P.; Denicola, A.; et al. Reactivity of hydrogen sulfide with peroxynitrite and other oxidants of biological interest. Free Radic. Biol. Med. 2011, 50, 196–205. [Google Scholar] [CrossRef] [PubMed]
  112. Cuevasanta, E.; Lange, M.; Bonanata, J.; Coitiño, E.L.; Ferrer-Sueta, G.; Filipovic, M.R.; Alvarez, B. Reaction of Hydrogen Sulfide with Disulfide and Sulfenic Acid to Form the Strongly Nucleophilic Persulfide. J. Biol. Chem. 2015, 290, 26866–26880. [Google Scholar] [CrossRef] [PubMed]
  113. Sundaresan, M.; Yu, Z.-X.; Ferrans, V.J.; Irani, K.; Finkel, T. Requirement for Generation of H2O2 for Platelet-Derived Growth Factor Signal Transduction. Science 1995, 270, 296–299. [Google Scholar] [CrossRef] [PubMed]
  114. Paulsen, C.E.; Truong, T.H.; Garcia, F.J.; Homann, A.; Gupta, V.; Leonard, S.E.; Carroll, K.S. Peroxide-dependent sulfenylation of the EGFR catalytic site enhances kinase activity. Nat. Chem. Biol. 2011, 8, 57–64. [Google Scholar] [CrossRef] [PubMed]
  115. Zivanovic, J.; Kouroussis, E.; Kohl, J.B.; Adhikari, B.; Bursac, B.; Schott-Roux, S.; Petrovic, D.; Miljkovic, J.L.; Thomas-Lopez, D.; Jung, Y.; et al. Selective Persulfide Detection Reveals Evolutionarily Conserved Antiaging Effects of S-Sulfhydration. Cell Metab. 2019, 30, 1152–1170. [Google Scholar] [CrossRef]
  116. O’Dell, T.J.; Hawkins, R.D.; Kandel, E.R.; Arancio, O. Tests of the roles of two diffusible substances in long-term potentiation: Evidence for nitric oxide as a possible early retrograde messenger. Proc. Natl. Acad. Sci. USA 1991, 88, 11285–11289. [Google Scholar] [CrossRef] [PubMed]
  117. Schuman, E.M.; Madison, D.V. A requirement for the intercellular messenger nitric oxide in long-term potentiation. Science 1991, 254, 1503–1506. [Google Scholar] [CrossRef]
  118. Haley, J.E.; Wilcox, G.L.; Chapman, P.F. The role of nitric oxide in hippocampal long-term potentiation. Neuron 1992, 8, 211–216. [Google Scholar] [CrossRef]
  119. Stevens, C.F.; Wang, Y. Reversal of long-term potentiation by inhibitors of haem oxygenase. Nature 1993, 364, 147–149. [Google Scholar] [CrossRef]
  120. Zhuo, M.; Small, S.A.; Kandel, E.R.; Hawkins, R.D. Nitric oxide and carbon monoxide produce activity-dependent long-term synaptic enhancement in hippocampus. Science 1993, 260, 1946–1950. [Google Scholar] [CrossRef]
  121. Garthwaite, J. Nitric oxide as a multimodal brain transmitter. Brain Neurosci. Adv. 2018, 2, 2398212818810683. [Google Scholar] [CrossRef] [PubMed]
  122. Garthwaite, J. Glutamate, nitric oxide and cell-cell signalling in the nervous system. Trends Neurosci. 1991, 14, 60–67. [Google Scholar] [CrossRef] [PubMed]
  123. Verma, A.; Hirsch, D.J.; Glatt, C.E.; Ronnett, G.V.; Snyder, S.H. Carbon monoxide: A putative neural messenger. Science 1993, 259, 381–384. [Google Scholar] [CrossRef] [PubMed]
  124. Oosumi, K.; Tsugane, M.; Ishigami MNagai, Y.; Iwai, T.; Oka, J.-I.; Kimura, H. Polysulfide activates TRP channels and increases intracellular Ca2+ in astrocytes. Bull. Jpn. Soc. Neurochem 2010, 49, 517. [Google Scholar] [CrossRef]
  125. Ogawa, H.; Takahashi, K.; Miura, S.; Imagawa, T.; Saito, S.; Tominaga MOhta, T. H2S functions as a nociceptive messenger throughtransient receptor potential ankyrin 1 (TRPA1) activation. Neuroscience 2012, 218, 335–343. [Google Scholar] [CrossRef] [PubMed]
  126. Nagahara, N.; Koike, S.; Nirasawa, T.; Kimura, H.; Ogasawara, Y. Alternative pathway of H2S and polysulfides production from sulfurated catalytic-cysteine of reaction intermediates of 3-mercaptopyruvate sulfurtransferase. Biochem. Biophys. Res. Commun. 2018, 496, 648–653. [Google Scholar] [CrossRef] [PubMed]
  127. Shigetomi, E.; Jackson-Weaver, O.; Huckstepp, R.T.; O’Dell, T.J.; Khakh, B.S. TRPA1 channels are regulators of astrocyte basal calcium levels and long-term potentiation via constitutive D-serine release. J. Neurosci. 2013, 33, 10143–10153. [Google Scholar] [CrossRef] [PubMed]
  128. Li, Y.L.; Wu, P.F.; Chen, J.G.; Wang, S.; Han, Q.Q.; Li, D.; Wang, W.; Guan, X.L.; Li, D.; Long, L.H.; et al. Activity-dependent sulfhydration signal controls N-methyl-D-aspartate subtype glutamate receptor-dependent synaptic plasticity via increasing D-serine availability. Antioxid. Redox Signal. 2017, 27, 398–414. [Google Scholar] [CrossRef]
  129. Mothet, J.P.; Billard, J.M.; Pollegioni, L.; Coyle, J.T.; Sweedler, J.V. Investigating brain d-serine: Advocacy for good practices. Acta Physiol. 2019, 226, e13257. [Google Scholar] [CrossRef]
  130. Eguchi, K.; Nakanishi, S.; Takagi, H.; Taoufiq, Z.; Takahashi, T. Maturation of a PKG-dependent retrograde mechanism for exoendocytic coupling of synaptic vesicles. Neuron 2012, 74, 517–529. [Google Scholar] [CrossRef]
  131. Garthwaite, J. NO as a multimodal transmitter in the brain: Discovery and current status. Br. J. Pharmacol. 2019, 176, 197–211. [Google Scholar] [CrossRef]
  132. Mitrukhina, O.B.; Yakovlev, A.V.; Sitdikova, G.F. The effects of hydrogen sulfide on the processes of exo- and endocytosis of synaptic vesicles in the mouse motor nerve endings. Biochem. Suppl. Ser. A Membr. Cell Biol. 2013, 7, 170–173. [Google Scholar] [CrossRef]
  133. Gerasimova, E.; Lebedeva, J.; Yakovlev, A.; Zefirov, A.; Giniatullin, R.; Sitdikova, G. Mechanisms of hydrogen sulfide (H2S) action on synaptic transmission at the mouse neuromuscular junction. Neuroscience 2015, 303, 577–585. [Google Scholar] [CrossRef] [PubMed]
  134. Kendrick, K.M. Use of microdialysis in neuroendocrinology. Methods Enzymol. 1989, 168, 182–205. [Google Scholar]
  135. Myeong, J.; Klyachko, V.A. Rapid astrocyte-dependent facilitation amplifies multi-vesicular release in hippocampal synapses. Cell Rep. 2022, 41, 111820. [Google Scholar] [CrossRef]
  136. Kimura, Y.; Shibuya, N.; Kimura, H. Sulfite protects neurons from oxidative stress. Br. J. Pharm. 2019, 176, 571–582. [Google Scholar] [CrossRef] [PubMed]
  137. Fukasawa, Y.; Segawa, H.; Kim, J.Y.; Chairoungdua, A.; Kim, D.K.; Matsuo, H.; Cha, S.H.; Endou, H.; Kanai, Y. Identification and characterization of a Na(+)-independent neutral amino acid transporter that associates with the 4F2 heavy chain and exhibits substrate selectivity for small neutral D- and L-amino acids. J. Biol. Chem. 2000, 275, 9690–9698. [Google Scholar] [CrossRef] [PubMed]
  138. Helboe, L.; Egebjerg, J.; Møller, M.; Thomsen, C. Distribution and pharmacology of alanine-serine-cysteine transporter 1 (asc-1) in rodent brain. Eur. J. Neurosci. 2003, 18, 2227–2238. [Google Scholar] [CrossRef] [PubMed]
  139. Bodner, O.; Radzishevsky, I.; Foltyn, V.N.; Touitou, A.; Valenta, A.C.; Rangel, I.F.; Panizzutti, R.; Kennedy, R.T.; Billard, J.M.; Wolosker, H. D-Serine Signaling and NMDAR-Mediated Synaptic Plasticity Are Regulated by System A-Type of Glutamine/D-Serine Dual Transporters. J. Neurosci. 2020, 40, 6489–6502. [Google Scholar] [CrossRef]
  140. Elrod, J.W.; Calvert, J.W.; Morrison, J.; Doeller, J.E.; Kraus, D.W.; Tao, L.; Jiao, X.; Scalia, R.; Kiss, L.; Szabo, C.; et al. Hydrogen sulfide attenuates myocardial ischemia-reperfusion injury by preservation of mitochondrial function. Proc. Natl. Acad. Sci. USA 2007, 104, 15560–15565. [Google Scholar] [CrossRef]
  141. Li, Z.; Xia, H.; Sharp TE 3rd LaPenna, K.B.; Elrod, J.W.; Casin, K.M.; Liu, K.; Calvert, J.W.; Chau, V.Q.; Salloum, F.N.; Xu, S.; et al. Mitochondrial H2S Regulates BCAA Catabolism in Heart Failure. Circ. Res. 2022, 131, 222–235. [Google Scholar] [CrossRef] [PubMed]
  142. Tripatara, P.; Patel, N.S.A.; Collino, M.; Gallicchio, M.; Kieswich, J.; Castiglia, S.; Benetti, E.; Stewart, K.N.; Brown, P.A.J.; Yaqoob, M.M.; et al. Generation of endogenous hydrogen sulfide by cystathionine γ–lyase limits renal ischemia/reperfusion injury and dysfunction. Lab. Investig. 2008, 88, 1038–1048. [Google Scholar] [CrossRef] [PubMed]
  143. Mikami, Y.; Shibuya, N.; Kimura, Y.; Nagahara, N.; Yamada, M.; Kimura, H. Hydrogen sulfide protects the retina from light-induced degeneration by the modulation of Ca2+ influx. J. Biol. Chem. 2011, 286, 39379–39386. [Google Scholar] [CrossRef] [PubMed]
  144. Cheung, S.H.; Lau, J.Y.W. Hydrogen sulfide mediates athero-protection against oxidative stress via S-sulfhydration. PLoS ONE 2018, 13, e0194176. [Google Scholar] [CrossRef] [PubMed]
  145. Kaziród, K.; Myszka, M.; Dulak, J.; Łoboda, A. Hydrogen sulfide as a therapeutic option for the treatment of Duchenne muscular dystrophy and other muscle-related diseases. Cell Mol. Life Sci. 2022, 79, 608. [Google Scholar] [CrossRef] [PubMed]
  146. Pecze, L.; Pelsoczi, P.; Kecskés, M.; Winter, Z.; Papp, A.; Kaszás, K.; Letoha, T.; Vizler, C.; Oláh, Z. Resiniferatoxin mediated ablation of TRPV1+ neurons removes TRPA1 as well. Can. J. Neurol Sci. 2009, 36, 234–241. [Google Scholar] [CrossRef] [PubMed]
  147. Ichinohe, A.; Kanaumi, T.; Takashima, S.; Enokido, Y.; Nagai, Y.; Kimura, H. Cystathionine beta-synthase is enriched in the brains of Down’s patients. Biochem. Biophys. Res. Commun. 2005, 338, 1547–1550. [Google Scholar] [CrossRef]
  148. Kamoun, P.; Belardinelli, M.C.; Chabli, A.; Lallouchi, K.; Chadefaux-Vekemans, B. Endogenous hydrogen sulfide overproduction in Down syndrome. Am. J. Med. Genet. A 2003, 116A, 310–311. [Google Scholar] [CrossRef]
  149. Marechal, D.; Brault, V.; Leon, A.; Martin, D.; Lopes Pereira, P.; Loaëc, N.; Birling, M.C.; Friocourt, G.; Blondel, M.; Herault, Y. Cbs overdosage is necessary and sufficient to induce cognitive phenotypes in mouse models of Down syndrome and interacts genetically with Dyrk1a. Hum. Mol. Genet. 2019, 28, 1561–1577. [Google Scholar] [CrossRef]
  150. Panagaki, T.; Randi, E.B.; Augsburger, F.; Szabo, C. Overproduction of H2S, generated by CBS, inhibits mitochondrial Complex IV and suppresses oxidative phosphorylation in Down syndrome. Proc. Natl. Acad. Sci. USA 2019, 116, 18769–18771. [Google Scholar] [CrossRef]
  151. Tiranti, V.; Viscomi, C.; Hildebrandt, T.; Di Meo, I.; Mineri, R.; Tiveron, C.; Levitt, M.D.; Prelle, A.; Fagiolari, G.; Rimoldi, M.; et al. Loss of ETHE1, a mitochondrial dioxygenase, causes fatal sulfide toxicity in ethylmalonic encephalopathy. Nat. Med. 2009, 15, 200–205. [Google Scholar] [CrossRef] [PubMed]
  152. Xiong, J.W.; Wei, B.; Li, Y.K.; Zhan, J.Q.; Jiang, S.Z.; Chen, H.B.; Yan, K.; Yu, B.; Yang, Y.J. Decreased plasma levels of gasotransmitter hydrogen sulfide in patients with schizophrenia: Correlation with psychopathology and cognition. Psychopharmacology 2018, 235, 2267–2274. [Google Scholar] [CrossRef] [PubMed]
  153. Topcuoglu, C.; Bakirhan, A.; Yilmaz, F.M.; Neselioglu, S.; Erel, O.; Sahiner, S.Y. Thiol/disulfide homeostasis in untreated schizophrenia patients. Psychiatry Res. 2017, 251, 212–216. [Google Scholar] [CrossRef] [PubMed]
  154. Ide, M.; Ohnishi, T.; Toyoshima, M.; Balan, S.; Maekawa, M.; Shimamoto-Mitsuyama, C.; Iwayama, Y.; Ohba, H.; Watanabe, A.; Ishii, T.; et al. Excess hydrogen sulfide and polysulfides production underlies a schizophrenia pathophysiology. EMBO Mol. Med. 2019, 11, e10695. [Google Scholar] [CrossRef] [PubMed]
  155. Lahti, A.C.; Koffel, B.; LaPorte, D.; Tamminga, C.A. Subanesthetic doses of ketamine stimulate psychosis in schizophrenia. Neuropsychopharmacology 1995, 13, 9–19. [Google Scholar] [CrossRef] [PubMed]
  156. Nagahara, N.; Nagano, M.; Ito, T.; Shimamura, K.; Akimoto, T.; Suzuki, H. Antioxidant enzyme, 3-mercaptopyruvate sulfurtransferase-knockout mice exhibit increased anxiety-like behaviors: A model for human mercaptolactate-cysteine disulfiduria. Sci. Rep. 2013, 3, 1986. [Google Scholar] [CrossRef] [PubMed]
  157. Wrobel, M.; Czubak, J.; Bronowicka-Adamska, P.; Jurkowska, H.; Adamek, D.; Papla, B. Is development of high-grade gliomas sulfur-dependent? Molecules 2014, 19, 21350–21362. [Google Scholar] [CrossRef]
  158. Shiota, M.; Naya, M.; Yamamoto, T.; Hishiki, T.; Tani, T.; Takahashi, H.; Suematsu, M. Gold-nanofève surface-enhanced Raman spectroscopy visualizes hypotaurine as a robust anti-oxidant consumed in cancer survival. Nat. Commun. 2018, 9, 1561. [Google Scholar] [CrossRef]
  159. Takano, N.; Sarfraz, Y.; Gilkes, D.M.; Chaturvedi, P.; Xiang, L.; Suematsu, M.; Semennza, G.L. Decreased expression of cystathionine b-synthase promotes glioma tumorigenesis. Mol. Cancer Res. 2014, 12, 1398–1406. [Google Scholar] [CrossRef]
  160. Singh, S.; Padovani, D.; Leslie, R.A.; Chiku, T.; Banerjee, R. Relative contributions of cystathionine beta-synthase and gamma-cystathionase to H2S biogenesis via alternative trans-sulfuration reactions. J. Biol. Chem. 2009, 284, 22457–22466. [Google Scholar] [CrossRef]
Biomolecules 14 00129 g001
Figure 1. H2S reduces the cysteine disulfide bond. (a). Sulfur-quinone-oxydoreductase (SQR) metabolizes H2S in mitochondria. The first step of the metabolism of H2S is the reduction of the cysteine disulfide bond of SQR in mitochondria. (b). H2S enhances the activity of NMDA receptors. H2S reduces the cysteine disulfide bond localized to the hinge of the ligand binding domain of the receptor to enhance the receptors activity. This figure is produced by modifying Kimura (2016) [35].
Figure 1. H2S reduces the cysteine disulfide bond. (a). Sulfur-quinone-oxydoreductase (SQR) metabolizes H2S in mitochondria. The first step of the metabolism of H2S is the reduction of the cysteine disulfide bond of SQR in mitochondria. (b). H2S enhances the activity of NMDA receptors. H2S reduces the cysteine disulfide bond localized to the hinge of the ligand binding domain of the receptor to enhance the receptors activity. This figure is produced by modifying Kimura (2016) [35].
Biomolecules 14 00129 g001
Biomolecules 14 00129 g002
Figure 2. Functional domains of CBS. NO and CO bind to the heme group located at the amino-terminus to suppress the activity, and SAM binds to the site located at the carboxy-terminus of CBS to enhance the activity. NO: nitric oxide, CO: carbon monoxide, PLP: pyridoxal 5′-phosphate, SAM: S-adenosyl-L-methionine.
Figure 2. Functional domains of CBS. NO and CO bind to the heme group located at the amino-terminus to suppress the activity, and SAM binds to the site located at the carboxy-terminus of CBS to enhance the activity. NO: nitric oxide, CO: carbon monoxide, PLP: pyridoxal 5′-phosphate, SAM: S-adenosyl-L-methionine.
Biomolecules 14 00129 g002
Biomolecules 14 00129 g003
Figure 3. Production of H2S and H2Sn by 3MST. 3MST produces H2S and H2Sn from 3MP, which is produced from L-cysteine and a-ketoglutarate by CAT. This pathway is localized both in the cytoplasm and mitochondria. 3MP is also produced from D-cysteine by DAO in the peroxisome. Peroxisome and mitochondria exchange their metabolites via vesicular trafficking [65]. 3MST: 3-mercaptopyruvate sulfurtransferase, CAT: cysteine amino transferase, DAO: D-amino acid oxidase.
Figure 3. Production of H2S and H2Sn by 3MST. 3MST produces H2S and H2Sn from 3MP, which is produced from L-cysteine and a-ketoglutarate by CAT. This pathway is localized both in the cytoplasm and mitochondria. 3MP is also produced from D-cysteine by DAO in the peroxisome. Peroxisome and mitochondria exchange their metabolites via vesicular trafficking [65]. 3MST: 3-mercaptopyruvate sulfurtransferase, CAT: cysteine amino transferase, DAO: D-amino acid oxidase.
Biomolecules 14 00129 g003
Biomolecules 14 00129 g004
Figure 4. A possible mechanism for the production of S-sulfurated molecules. (a). H2S2 produced by 3MST diffuses to react with molecules containing thiol to produce corresponding S-sulfurated molecules. (b). Alternatively, 3MST trans-sulfurates thiols to produce S-sulfurated molecules. This figure is produced by modifying Kimura (2020) [73].
Figure 4. A possible mechanism for the production of S-sulfurated molecules. (a). H2S2 produced by 3MST diffuses to react with molecules containing thiol to produce corresponding S-sulfurated molecules. (b). Alternatively, 3MST trans-sulfurates thiols to produce S-sulfurated molecules. This figure is produced by modifying Kimura (2020) [73].
Biomolecules 14 00129 g004
Biomolecules 14 00129 g005
Figure 5. Two pathways proposed for S-nitrosylating the target proteins. After NO is produced by NO synthase, it diffuses to reach the target cysteine residue to S-nitrosylate it, or heme proteins to react with heme. Alternatively, the complex of NO synthase and S-nitrosylase directly S-nitrosylates the target cysteine residues in the cell.
Figure 5. Two pathways proposed for S-nitrosylating the target proteins. After NO is produced by NO synthase, it diffuses to reach the target cysteine residue to S-nitrosylate it, or heme proteins to react with heme. Alternatively, the complex of NO synthase and S-nitrosylase directly S-nitrosylates the target cysteine residues in the cell.
Biomolecules 14 00129 g005
Biomolecules 14 00129 g006
Figure 6. S-sulfuration of cysteine residues of target proteins by H2Sn. TRPA1 channels and PTEN have two cysteine residues sensitive to S-sulfuration to regulate their activity. One cysteine residue is S-sulfurated to react with another thiol to generate a cysteine disulfide bond. PKGα monomer is S-sulfurated to react with another monomer to produce the active-form dimer. This figure is produced by modifying Kimura 2020 [73].
Figure 6. S-sulfuration of cysteine residues of target proteins by H2Sn. TRPA1 channels and PTEN have two cysteine residues sensitive to S-sulfuration to regulate their activity. One cysteine residue is S-sulfurated to react with another thiol to generate a cysteine disulfide bond. PKGα monomer is S-sulfurated to react with another monomer to produce the active-form dimer. This figure is produced by modifying Kimura 2020 [73].
Biomolecules 14 00129 g006
Biomolecules 14 00129 g007
Figure 7. H2S and H2S2 induce the release of neurotransmitters. H2S more efficiently induces the release of GABA and glutamate than H2S2. Both H2S and H2S2 induce D-serine release with a similar potency. H2S/H2S2 may alter the synaptic vesicle dynamics and/or transporters to facilitate the release of neurotransmitters. This figure is produced by modifying Furuie et al. (2023) [41].
Figure 7. H2S and H2S2 induce the release of neurotransmitters. H2S more efficiently induces the release of GABA and glutamate than H2S2. Both H2S and H2S2 induce D-serine release with a similar potency. H2S/H2S2 may alter the synaptic vesicle dynamics and/or transporters to facilitate the release of neurotransmitters. This figure is produced by modifying Furuie et al. (2023) [41].
Biomolecules 14 00129 g007
Biomolecules 14 00129 g008
Figure 8. H2S and H2S2 facilitate the induction of hippocampal long-term potentiation (LTP), a synaptic model of memory formation. H2S and H2S2 induce the release of glutamate and D-serine to enhance the activity of NMDA receptors. H2S reduces the cysteine disulfide bond localized to the amino terminus of NMDA receptors, while H2S2 activate TRPA1 channels in astrocytes to increase the activity of nearby neurons to facilitate the induction of LTP. This figure is produced by modifying Furuie et al. (2023) [41].
Figure 8. H2S and H2S2 facilitate the induction of hippocampal long-term potentiation (LTP), a synaptic model of memory formation. H2S and H2S2 induce the release of glutamate and D-serine to enhance the activity of NMDA receptors. H2S reduces the cysteine disulfide bond localized to the amino terminus of NMDA receptors, while H2S2 activate TRPA1 channels in astrocytes to increase the activity of nearby neurons to facilitate the induction of LTP. This figure is produced by modifying Furuie et al. (2023) [41].
Biomolecules 14 00129 g008
Biomolecules 14 00129 g009
Figure 9. The involvement of TRPA1 channels in the metabolism of sulfur containing amino acids and other neurotransmitters. Deficiency of TRPA1 channels decreases the levels of methionine, cysteine, glycine, and 3MST, while increases those of GABA [40,41]. Suppression of TRPA1 channels by resiniferatoxin, an antagonist of TRPV1 and TRPA1 channels, upregulates spermidine/spermine N(1)-acetyltransferase 2 (SAT2), which regulate the levels of glutamate, while suppresses the regulator of G protein signalling 7 (RGS7), which regulates synaptic plasticity and GABA signalling [42].
Figure 9. The involvement of TRPA1 channels in the metabolism of sulfur containing amino acids and other neurotransmitters. Deficiency of TRPA1 channels decreases the levels of methionine, cysteine, glycine, and 3MST, while increases those of GABA [40,41]. Suppression of TRPA1 channels by resiniferatoxin, an antagonist of TRPV1 and TRPA1 channels, upregulates spermidine/spermine N(1)-acetyltransferase 2 (SAT2), which regulate the levels of glutamate, while suppresses the regulator of G protein signalling 7 (RGS7), which regulates synaptic plasticity and GABA signalling [42].
Biomolecules 14 00129 g009
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Kimura, H. Hydrogen Sulfide (H2S)/Polysulfides (H2Sn) Signalling and TRPA1 Channels Modification on Sulfur Metabolism. Biomolecules 2024, 14, 129. https://doi.org/10.3390/biom14010129

AMA Style

Kimura H. Hydrogen Sulfide (H2S)/Polysulfides (H2Sn) Signalling and TRPA1 Channels Modification on Sulfur Metabolism. Biomolecules. 2024; 14(1):129. https://doi.org/10.3390/biom14010129

Chicago/Turabian Style

Kimura, Hideo. 2024. "Hydrogen Sulfide (H2S)/Polysulfides (H2Sn) Signalling and TRPA1 Channels Modification on Sulfur Metabolism" Biomolecules 14, no. 1: 129. https://doi.org/10.3390/biom14010129

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop