H2S is synthesized via CBS/CSE pathway and triggered by cold conditions during Agaricus bisporus storage

BACKGROUND: H2S is proved to be functioning as a signaling molecule in an array of physiological processes in the plant and animal kingdom. However, the H2S synthesis pathway and the responses to cold conditions remain unclear in postharvest mushroom. RESULTS: The biosynthesis of H2S in the Agaricus bisporus mushroom tissues exhibited an increasing tendency during postharvest storage and was significantly triggered by cold treatment. The cystathionine clyase (AbCSE) and cystathionine b-synthase (AbCBS) genes were cloned and proved responsible for H2S biosynthesis. Furthermore, transcriptional and posttranscriptional regulation of AbCSE and AbCBS were crucial for the enzyme activities and subsequent H2S levels. However, the AbMST was not involved in this process. Moreover, the AbCSE and AbCBS genes displayed low identity to the characterized genes, but typical catalytic domains, activity sites, subunit interface sites, and cofactor binding sites were conserved in the respective protein sequences, as revealed by molecular modeling and docking study. The potential transcription factors responsible for the H2S biosynthesis in cold conditions were also provided. CONCLUSIONS: The H2S biosynthetic pathway in postharvest mushroom was unique and distinct to that of other horticultural products.

Beneficial effects of octreotide in alcohol-induced neuropathic pain. Role of H 2S, BDNF, TNF-α and Nrf2

ABSTRACT Purpose To explore the role and molecular mechanisms of neuroprotective effects of octreotide in alcohol-induced neuropathic pain. Methods Male Wistar rats were employed and were administered a chronic ethanol diet containing 5% v/v alcohol for 28 days. The development of neuropathic pain was assessed using von Frey hair (mechanical allodynia), pinprick (mechanical hyperalgesia) and cold acetone drop tests (cold allodynia). The antinociceptive effects of octreotide (20 and 40 µg·kg-1) were assessed by its administration for 28 days in ethanol-treated rats. ANA-12 (0.25 and 0.50 mg·kg-1), brain-derived neurotrophic factor (BDNF) receptor blocker, was coadministered with octreotide. The sciatic nerve was isolated to assess the biochemical changes including hydrogen sulfide (H2S), cystathionine β synthase (CBS), cystathionine γ lyase (CSE), tumor necrosis factor-α (TNF-α), BDNF and nuclear factor erythroid 2-related factor 2 (Nrf2). Results Octreotide significantly attenuated chronic ethanol-induced neuropathic pain and it also restored the levels of H2S, CBS, CSE, BDNF, Nrf2 and decreased TNF-α levels. ANA-12 abolished the effects of octreotide on pain, TNF-α, BDNF, Nrf2 without any significant effects on H2S, CBS, CSE. Conclusions Octreotide may attenuate the behavioral manifestations of alcoholic neuropathic pain, which may be due to an increase in H2S, CBS, CSE, BDNF, Nrf2 and a decrease in neuroinflammation.

Effect of L-cysteine on colonic motility and the underlying mechanism / 生理学报

The purpose of the present study is to investigate the effect of L-cysteine on colonic motility and the underlying mechanism. Immunohistochemical staining and Western blot were used to detect the localization of the HS-generating enzymes cystathionine-β-synthase (CBS) and cystathionine-γ-lyase (CSE). Organ bath system was used to observe the muscle contractile activities. Whole-cell patch-clamp technique was applied to record ionic channels currents in colonic smooth muscle cells. The results showed that both CBS and CSE were localized in mucosa, longitudinal and circular muscle and enteric neurons. L-cysteine had a dual effect on colonic contraction, and the excitatory effect was blocked by pretreatment with CBS inhibitor aminooxyacetate acid (AOAA) and CSE inhibitor propargylglycine (PAG); L-cysteine concentration-dependently inhibited L-type calcium channel current (I) without changing the characteristic of L-type calcium channel (P < 0.01); In contrast, the exogenous HS donor NaHS increased I at concentration of 100 μmol/L, but inhibited I and modified the channel characteristics at concentration of 300 μmol/L (P < 0.05); Furthermore, L-cysteine had no effect on large conductance calcium channel current (I), but NaHS significantly inhibited I (P < 0.05). These results suggest that L-cysteine has a potential dual effect on colonic smooth muscle and the inhibitory effect might be directly mediated by L-type calcium channel while the excitatory effect might be mediated by endogenous HS.

CBS promoter hypermethylation increases the risk of hypertension and stroke

OBJECTIVES: Cystathionine β-synthase is a major enzyme in the metabolism of plasma homocysteine. Hyperhomocysteinemia is positively associated with hypertension and stroke. The present study was performed to examine the possible effects of Cystathionine β-synthase promoter methylation on the development of hypertension and stroke. METHODS: Using quantitative methylation-specific PCR, we determined the Cystathionine β-synthase methylation levels in 218 healthy individuals and 132 and 243 age- and gender-matched stroke and hypertensive patients, respectively. The relative changes in Cystathionine β-synthase promoter methylation were analyzed using the 2-ΔΔCt method. The percent of the methylated reference of Cystathionine β-synthase was used to represent the Cystathionine β-synthase promoter methylation levels. RESULTS: In this study, the Cystathionine β-synthase promoter methylation levels of hypertensive and stroke participants were both higher than that of the healthy individuals (median percentages of the methylated reference were 50.61%, 38.05% and 30.53%, respectively, all p<0.001). Multivariable analysis showed that Cystathionine β-synthase promoter hypermethylation increased the risk of hypertension [odds ratio, OR (95% confidence interval, CI)=1.035 (1.025-1.045)] and stroke [OR (95% CI)=1.015 (1.003-1.028)]. The area under the curve of Cystathionine β-synthase promoter methylation was 0.844 (95% CI: 0.796-0.892) in male patients with hypertension and 0.722 (95% CI: 0.653-0.799) in male patients with stroke. CONCLUSION: Cystathionine β-synthase promoter hypermethylation increases the risk of hypertension and stroke, especially in male patients.

The Role of CBS in Injury Time Estimation after Brain Contusion / 法医学杂志

OBJECTIVES@#To observe the changes of cystathionine β-synthase （CBS） expression in the cerebral cortex after brain contusion at different times.@*METHODS@#An experimental model of traumatic brain injury （TBI） in mice was established by an improved weight-drop device. Then Western blotting and immunohistochemical examination were used to detect the CBS expression in cerebral cortex around injury at different time points （1 h, 6 h, 12 h, 1 d, 2 d, 3 d, 7 d）.@*RESULTS@#The results of Western blotting revealed that the expression level of CBS was down-regulated and reached its lowest level at the 3rd days after injury, and then restored to normal level after 7 days. The results of immunohistochemistry showed that CBS was present in the normal brain cortex. CBS expression gradually decreased at the 3rd days after injury, and then restored to normal level after 7 days.@*CONCLUSIONS@#CBS has the potential to be a reference index for time estimation after brain contusion in forensic practice.

Polymorphisms in methylenetetrahydrofolate reductase and cystathionine beta-synthase in oral cancer - a case-control study in southeastern Brazilians / Polimorfismos em metilenotetrahidrofolato redutase, cistationina beta-sintase no câncer de boca - um estudo de caso-controle no Sudeste brasileiro

ABSTRACT INTRODUCTION: Oral squamous cell carcinoma (OSCC) is a serious public health problem, due to its high mortality rate and worldwide rising incidence. OSCC susceptibility is mediated by interactions between genetic and environmental factors. Studies suggest that genetic variants encoding enzymes involved in folate metabolism may modulate OSCC risk by altering DNA synthesis/repair and methylation process. OBJECTIVE: The goals of this study were to evaluate the association of three genotypic polymorphism (MTHFR C677T, MTHFR A1298C and CBS 844ins68) and oral cancer risk in southeastern Brazilians and evaluate the interactions between polymorphisms and clinical histopathological parameters. METHODS: This case-control study included 101 cases and 102 controls in the state of Espírito Santo, Brazil. MTHFR genotyping was done by PCR-RFLP (polymerase chain reaction - restriction fragment length polymorphism) and CBS genotyping by PCR (polymerase chain reaction) analysis. RESULTS: MTHFR C677T polymorphism was associated with lymph node involvement. Genotype CT + TT acted as a protective factor. MTHFR A1298C AC + CC genotype was associated with tumor differentiation, and possibly with a better prognosis. In risk analysis, no correlation was observed between genotypes and OSCC. CONCLUSION: We concluded that MTHFR C677T, MTHFR A1298C and CBS 844ins68 polymorphisms were not associated with OSCC risk in southeastern Brazilians; however, we suggest a prognosis effect associated with MTHFR C677T and A1298C polymorphisms in OSCC.

Resumo Introdução: O carcinoma espinocelular oral (CECO) trata-se de um importante problema de saúde pública, devido à elevada taxa de mortalidade e incidência crescente em todo o mundo. A susceptibilidade ao CECO é mediada por interações entre fatores genéticos e ambientais. Estudos sugerem que as variantes genéticas que codificam as enzimas envolvidas no metabolismo do folato podem modular o risco de CECO, alterando a síntese/reparação do DNA e o processo de metilação. Objetivo: Os objetivos deste estudo foram avaliar a associação de três polimorfismos genotípicos (MTHFR C677T, MTHFR A1298C e CBS 844ins68) e o risco de câncer oral em brasileiros da região Sudeste, e avaliar as interações entre polimorfismos e parâmetros clínico-histopatológicos. Método: Este estudo de caso-controle incluiu 101 casos e 102 controles no estado do Espírito Santo, Brasil. A genotipagem do polimorfismo MTHFR foi realizada por PCR-RFLP (Reação de Polimerase em Cadeia - Polimorfismo no Comprimento de Fragmento de Restrição) e a do CBS por análise da PCR (Reação de Polimerase em Cadeia). Resultados: O polimorfismo MTHFR C677T foi associado ao envolvimento de gânglios linfáticos. O genótipo CT + TT atuou como um fator protetor. O genótipo MTHFR A1298C AC + CC foi associado à diferenciação do tumor e, possivelmente, a um prognóstico melhor. Na análise de risco, a correlação entre os genótipos e o CECO não foi observada. Conclusão: Concluímos que os polimorfismos MTHFR C677T, MTHFR A1298C e CBS 844ins68 não estão associados ao risco de CECO nos brasileiros da região Sudeste; no entanto, sugerimos um efeito prognóstico associado aos polimorfismos MTHFR C677T e A1298C em CECO.

Upregulation of cystathionine β-synthetase in the arcuate nucleus produces pain hypersensitivity via PKC upregulation and GluN2B phosphorylation in rats with chronic pancreatitis / 生理学报

Hydrogen sulfide (HS) contributes to visceral hyperalgesia in primary sensory neurons, but its role in central nervous system remains largely unknown. This study was to investigate the roles and underlying mechanisms of HS and its endogenous synthesis enzymes in the arcuate nucleus (ARC) in rat pancreatic hyperalgesia. Chronic pancreatitis (CP) was induced in male adult Sprague-Dawley rats by intra-pancreatic ductal injection of trinitrobenzene sulfonic acid (TNBS). Abdominal hyperalgesia was assessed by referred somatic behaviors to mechanical stimulation of rat abdomen. Western blot analysis was performed to detect protein expression in the ARC. CP markedly upregulated cystathionine β-synthetase (CBS) expression but did not alter cystathionine-γ-lyase level in the ARC at 4 weeks after TNBS injection. Although the expression of total GluN2B was not altered, CP greatly enhanced the phosphorylation level of GluN2B in the ARC when compared with age- and sex-matched control rats. CP also significantly increased expression of protein kinase Cγ (PKCγ) in the ARC. Arcuate microinjection of O-(Carboxymethyl) hydroxylamine hemihydrochloride (AOAA, an inhibitor of CBS) significantly attenuated abdominal pain in CP rats in a dose-dependent manner and reversed the CP-induced upregulation of p-GluN2B and PKCγ in the ARC. Furthermore, the GluN2B inhibitor or specific PKC inhibitor chelerythrine significantly attenuated abdominal hyperalgesia in CP rats. The p-GluN2B expression was also suppressed by PKC inhibitor. Taken together, our results suggest that the upregulation of CBS in the ARC leads to an activation of GluN2B via PKCγ, which may play an important role in generation of pain hypersensitivity of CP.

Actions of endogenous hydrogen sulfide on colonic hypermotility in a rat model of chronic stress / 生理学报

The present study was designed to investigate the potential role of endogenous hydrogen sulfide (H2S) in chronic stress-induced colonic hypermotility. Male Wistar rats were submitted daily to 1 h of water avoidance stress (WAS) or sham WAS (SWAS) for 10 consecutive days. The total number of fecal pellets was counted at the end of each 1 h of WAS or SWAS session. Organ bath recordings were used to test the colonic motility. H₂S production of colon was determined, and immunohistochemistry and Western blot were performed on rat colonic samples to detect the distribution and expression of H₂S-producing enzymes. The results showed that i) repeated WAS increased the number of fecal pellets per hour and the area under the curve (AUC) of the spontaneous contractions of colonic strips (P < 0.05), ii) repeated WAS decreased the endogenous production of H₂S and the expression of H₂S-producing enzymes in the colon devoid of mucosa and submucosa (P < 0.001), iii) cystathionine-γ-lyase (CSE) was strongly expressed in the cytosols of the circular and longitudinal smooth muscle cells and the nucleus of the myenteric plexus neurons, iv) cystathionine-β-synthase (CBS) was primarily localized in the cytosols of myenteric plexus neurons and weakly localized in the epithelial cells and v) inhibitors of H₂S-producing enzymes increased the contractile activity of colonic strips in the SWAS rats (P < 0.001). In conclusion, the results suggest that the colonic hypermotility induced by repeated WAS may be associated with the decreased production of endogenous H2S.

Association of cystathionine β-synthase gene polymorphisms with essential hypertension in ethnic Uyghurs and Hans from Xinjiang / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the cystathione beta synthase (CBS) gene T833C, G919A, 844ins68 polymorphisms and plasma homocysteine (Hcy) levels in ethnic Uyghur and Han patients with essential hypertension (EH) in Xinjiang.</p><p><b>METHODS</b>Four hundred twenty nine cases including 211 Uyghur and 218 Han EH patients were recruited, whilst 410 healthy individuals including 210 Uyghurs and 200 Hans were used as the controls. Amplification refractory mutation system (ARMS) was adopted to analyze the CBS gene polymorphisms including T833C, G919A and 844ins68. Enzymoimmunoassay was applied to determine the plasma level of Hcy. Chemiluminescence was applied to determine the plasma folic acid and vitamin B12.</p><p><b>RESULTS</b>Compared with the controls, the plasma Hcy level was significantly higher in the EH group in both ethnic Uyghurs and Hans (P < 0.05). Plasma levels of Hcy in T833C, G919A genotypes (for both heterozygotes and homozygotes) were statistically higher than wild types (P < 0.05). A significant difference was detected in G919A polymorphism between the EH patients and controls in both Uyghur and [CM(144.5mm] Han ethnics (Uyghur: x² = 10.264, P < 0.01; Han: x² = 23.075, P < 0.01), and in T833C between the EH patients and controls in ethnic Uyghurs (x² = 40.254, P < 0.01). Logistic regression analysis indicated that age (OR=1.151, P=0.047, 95% CI = 1.002-1.323), T833C (CC) (OR = 1.078, P = 0.003, 95% CI = 1.043-1.114), obesity (OR = 1.284, P = 0.021, 95% CI = 1.038-1.590), hyperhomocysteine (OR = 3.296, P = 0.016, 95% CI = 1.244-8.733) were independent risk factors for EH among ethnic Uygurs, while age (OR = 1.162, P = 0.007, 95% CI = 1.042-1.297), obesity (OR = 3.501, P = 0.003, 95% CI = 1.521-8.060), hyperhomocysteine (OR = 1.046, P = 0.031, 95% CI = 1.011-1.459) were independent risk factors for EH in ethnic Hans after adjusting for confounding factors.</p><p><b>CONCLUSION</b>Plasma level of Hcy is associated with ethnic Uyghur and Han patients with EH in Xinjiang. CBS gene T833C CC genotype may be associated with the EH among Uyghur ethnics.</p>

Expressions of CSE and CBS in the corpus cavernosum of spontaneous hypertensive rats / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the expressions of cystathionine gamma-lyase (CSE) and cystathionine beta-synthase (CBS) in the corpus cavernosum of spontaneous hypertensive rats (SHR) and their relationship with erectile dysfunction.</p><p><b>METHODS</b>This study included 10 male SHRs and 10 healthy male Wistar-Kyoto (WKY) rats as controls, all aged 12 weeks. We applied a series of electric stimuli to the major pelvic ganglions of the rats, observed changes in the ratio of intracavernosal to mean arterial blood pressure (ICP/MAP), measured the levels of serum testosterone (T) and endogenous H2S, and determined the expressions of CSE and CBS in the corpus cavernosum by Western blot and immunohistochemistry.</p><p><b>RESULTS</b>No obvious difference was found in the serum T level between the two groups. Compared with the WKY rats, the SHRs showed significant reduction in the ICP/MAP ratio, the contents of plasma H2S ([21.92 +/- 2.75] micromol/L vs [10.49 +/- 1.35] micromol/L, P < 0.05) and endogenous corpus cavernosal H2S ([87.67 +/- 2.12] nmol/mg prot vs [52.60 +/- 3.44] nmol/mg prot, P < 0.05), the level of endogenous H2S synthesis ([4.35 +/- 0.32] nmol/mg per min vs [1.14 +/- 0.07] nmol/mg per min, P < 0.05) and the expressions of CBS and CSE (P < 0.05). Immunohistochemistry showed that CSE and CBS were distributed mainly in the smooth muscle cells and vascular endothelial cells of the corpus cavernosum. The ICP/MAP ratio was highly positively correlated with the expressions of CSE (r = 0.977, P < 0.05) and CBS (r = 0.955, P < 0.05) in the corpus cavernosal tissue.</p><p><b>CONCLUSION</b>Hypertension inhibits endogenous H2S synthesis by suppressing the expressions of CSE and CBS in the corpus cavernosum, which might be related with hypertension-induced reduction of erectile function.</p>

An association study between gene polymorphism of the key enzyme's folacin metabolism pathway and plasmatic homocysteine levels in fertile woman / 中华预防医学杂志

<p><b>OBJECTIVE</b>The effect of the gene polymorphism for the key enzyme's folacin metabolism pathway on plasmatic homocysteine (Hcy) levels in fertile woman was observed.</p><p><b>METHODS</b>The subjects were from Shaoxing City, Jiangsu province in 2012, the selection criteria for the women of childbearing age were between 20-45 years old, with an average age of 28.2 (95%CI:27.8-28.6) years old. Sample collection continued uninterrupted lasted seven days, a total of 535 samples were collected, venous blood with EDTA addition or sodium citrate to anticoagulant. After separation, the blood cells and blood plasma were cryopreserved. DNA was extracted using spin column method. All the samples were selected for the gene polymorphism testing of the key enzyme's on folate metabolism and monitoring of plasmatic Hcy level.</p><p><b>RESULTS</b>Eight single nucleotide polymorphism (SNP) sites of methylenetetrahydrofolate reductase gene (MTHFR) , methionine synthase gene (MS) , synthetic methionine reductase gene (MSR) and cystathionine β synthase gene (CBS) were detected. It was found the genotype AA of the SNP sites-rs1801131 would result higher plasmatic Hcy levels (8.99 µmol/L) than the genotypes CC (7.81 µmol/L) and CA(8.38 µmol/L) (P < 0.01) . Similarly, the genotype TT of the SNP sites-rs1801133 was significantly responded to the increasing of Hcy levels (11.10 µmol/L) than the genotype CC (8.15 µmol/L) and CT (8.45 µmol/L), (P < 0.01) . The two sites of genotype combination of AA-TT could also result in the significant increase of Hcy levels (11.02 µmol/L) than other combined genotypes (genotypes CC-CC, CA-CC, CA-CT, AA-CC, AA-CT), especially the genotype CC-CC. And the risk factor was 1.41 (95CI:1.20-1.66) times over the genotype CC-CC.</p><p><b>CONCLUSION</b>The gene mutations of two SNP sites rs1801131 and rs1801133 in MTHFR would increase Hcy levels.</p>

Endogenous hydrogen sulfide and androgen deficiency-induced erectile dysfunction in rats / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the role of endogenous hydrogen sulfide (H2S) in erectile dysfunction (ED) induced by androgen deficiency.</p><p><b>METHODS</b>We randomly divided 30 eight-week-old healthy male SD rats into six groups: 2-week control (A), 4-week control (B), 2-week castration (C), 4-week castration (D), 2-week castration + androgen replacement (E), and 4-week castration + androgen replacement (F), those in groups E and F subcutaneously injected with testosterone propionate (TP) at the physiological dose of 3 mg/kg per day after castration, while those in the other groups with isodose oil instead. At 2 and 4 weeks after operation, we determined the level of serum testosterone (T) , intracavernous pressure (ICP) , mean carotid arterial pressure (MAP) of the rats, measured the concentration of H2S in the plasma and corpus cavernosum tissue, and detected the expressions of cystathionine-P3-synthase (CBS) and cystathionine-gamma-lyase (CSE) by immunohistochemistry and Western blot.</p><p><b>RESULTS</b>The serum T level was significantly lower in group C ([0.63 +/- 0.15] nmol/L) than in A ( [ 16.55 +/- 4.17] nmol/L) and E ( [ 18.99 +/- 4.62] nmol/L) (P <0.05), as well as in group D ([0.70 +/-0.22] nmol/L) than in B ([15.44 +/-5.18] nmol/L) and F ([20.99 +/-6.41] nmol/L) (P <0. 05) , and so were ICP/MAP after 5 and 7 V electrical stimulation of the pelvic ganglia (P <0. 05) , H2 S concentration (P <0.05), and the expressions of CBS and CSE (P <0.05). The expressions of CBS and CSE proteins were also significantly decreased in group C as compared with D (P <0.05).</p><p><b>CONCLUSION</b>The reduced expressions of CBS and CSE may inhibit the H2 S signaling pathway, which might be one of the mechanisms underlying androgen deficiency-induced ED in rats.</p>

Immunohistochemccal approach reveals localizatin of cystathionine--lyase and ccystathionine--synthetase in ethanol-induced gastric mucosa damage in mice

Context Hydrogen sulphide (H2S) has been proved to be a neuromodulator and contributes to the maintenance of gastric mucosal integrity in damage caused by anti-inflammatory nonsteroidal drugs. Previously, we demonstrated that H2S synthesis is essential to gastric protection against ethanol. Objective To better understanding the role of H2S and the detailed localization of its production in both normal and injured stomach due to ethanol injection, we studied the expression of cystathionine-γ-lyase (CSE) and cystathionine-β-synthetase (CBS) isoforms in gastric mucosa of mice treated with saline or 50% ethanol. Methods Mice were treated by gavage with saline or 50% ethanol (0.5 mL/25 g). After 1 hour, mice were sacrificed, and gastric tissue was evaluated by histological and immunohistochemical analysis specific for CSE and CBS. Results We have demonstrated a non-specific expression of CBS in the normal gastric mucosa and expression of CSE occurring mainly in the parietal cells of the animals treated with ethanol. Conclusion Thus, we demonstrated that the expression of CBS appears to be constitutive and diffuse across the gastric epithelium, while the expression of CSE appears to be induced in parietal cells by damage agents such as ethanol. .

Contexto O sulfeto de hidrogênio (H2S) tem sido mostrado como um neuromodulador e contribuidor para a manutenção da integridade da mucosa gástrica na lesão causada por drogas antiinflamatórias não esteroidais. Previamente, demonstramos que a síntese de H2S é essencial para a proteção da mucosa gástrica contra a administração de etanol. Objetivo Para compreender o papel do H2S e a localização detalhada de sua produção no estômago normal e após lesão induzida pela administração de etanol, estudou-se a expressão das isoformas cistationina-γ-liase (CSE) e cistationina-β-sintetase (CBS) na mucosa gástrica de camundongos tratados com salina ou etanol 50%. Métodos Os camundongos foram tratados por gavagem com salina ou etanol 50% (0,5 mL/25 g). Após 1 hora, os camundongos foram sacrificados e os tecidos gástricos foram avaliados por análise histológica e imunoistoquímica específica para CBS e CSE. Resultados Foi demonstrado expressão não específica de CBS na mucosa gástrica normal e expressão de CSE ocorrendo principalmente nas células parietais dos animais tratados com etanol. Conclusão Assim, demonstramos que a expressão de CBS parece ser constitutiva e difusa através do epitélio gástrico, enquanto a expressão de CSE parece ser induzida nas células parietais por agentes lesivos como o etanol. .

Change in plasma H2S level and therapeutic effect of H2S supplementation in tubulointerstitial fibrosis among rats with unilateral ureteral obstruction / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To observe the level in plasma hydrogen sulfide (H2S) and the expression of cystathionine beta-synthase (CBS) and cystathionine gamma-lyase (CSE) (two key synthetases for endogenous H2S generation in the kidney) in obstructed kidney tissue among rats with tubulointerstitial fibrosis (TIF) induced by unilateral ureteral obstruction (UUO), and to explore the role of H2S in TIF.</p><p><b>METHODS</b>Ninety-six male Sprague-Dawley rats were randomly divided into sham-operated, model, low-dose NaHS and high-dose NaHS groups (n=24 each). TIF was induced by UUO in the model, low-dose NaHS and high-dose NaHS groups. The low-dose and high-dose NaHS groups were intraperitoneally injected with NaHS (1.4 and 7.0 μmol/kg respectively) twice daily immediately after operation, and the sham-operated and model groups were intraperitoneally injected with an identical volume of normal saline. In each group, 8 rats were randomly selected and sacrificed at 7, 14 or 21 days after operation. Plasma H2S concentration was measured by deproteinization. The obstructed kidney tissue was subjected to hematoxylin and eosin staining and Masson staining, and the renal tubulointerstitial injury was evaluated under a microscope. mRNA and protein expression of CBS and CSE in the obstructed kidney tissue was measured by RT-PCR and immunohistochemistry respectively.</p><p><b>RESULTS</b>The degree of UUO-induced renal tubulointerstitial injury was negatively correlated with plasma H2S concentration in (r=-0.891, P<0.01). With H2S supplementation, renal tubulointerstitial injury was reduced (P<0.01), the expression of mRNA and protein of CBS and CSE in the kidney tissue and plasma H2S level were upregulated (P<0.01), and the degree of TIF was reduced (P<0.01). There were no significant differences in plasma H2S level and mRNA and protein expression of CBS and CSE between the low-dose and high-dose NaHS groups (P>0.05).</p><p><b>CONCLUSIONS</b>H2S is involved in the development of UUO-induced TIF, and the CBS/H2S and CSE/H2S systems play key roles in this process. H2S supplementation can delay the progression of TIF.</p>

Expressions of cystathionine-beta-synthase and cystathionine-gamma-lyase in the corpus cavernosum smooth muscle of castrated rats / 中华男科学杂志

<p><b>OBJECTIVE</b>To study the expressions of cystathionine-beta-synthase (CBS) and cystathionine-gamma-lyase (CSE) in the corpus cavernosum smooth muscle of castrated rats and their roles in erectile dysfunction after castration.</p><p><b>METHODS</b>We randomly assigned 40 eight-week-old male SD rats to groups A (2-week sham-operation), B (4-week sham-operation), C (2-week castration) and D (4-week castration). We determined the level of serum testosterone (T) and the expressions of CBS and CSE in the corpus cavernosum smooth muscle of the rats after operation using immunohistochemistry and RT-PCR.</p><p><b>RESULTS</b>The T level was significantly decreased in groups C ([11.85 +/- 6.73] nmol/L) and D ([1.96 +/- 1.23] nmol/L) as compared with A ([89.65 +/- 17.13] nmol/L) and B ([106.75 +/- 19.68] nmol/L) (P < 0.05). CBS and CSE were expressed in all groups of rats, but the relative expressions of CBS and CSE mRNA were significantly lower in groups C (0.93 +/- 0.14 and 0.87 +/- 0.20) and D (0.79 +/- 0.17 and 0.71 +/- 0.12) than in A (2.13 +/- 0.65 and 1.93 +/- 0.15) and B (2.07 +/- 0.53 and 1.89 +/- 0.45) (P < 0. 05), so were the optical density values (IA) of the CBS and CSE proteins, 130.35 +/- 23.56 and 93.56 +/- 36.64 in group C and 80.29 +/- 29.65 and 58.56 +/- 19.95 in group D, as compared with 310.57 +/- 130.56 and 269.56 +/- 116.76 in group A and 349.68 +/-112.35 and 298.35 +/- 100.76 in group B (P < 0.05). The androgen level was positively correlated with the expressions of CBS and CSE in the corpus cavernosum smooth muscle of the rats.</p><p><b>CONCLUSION</b>Androgen regulates erectile function via the expressions of CBS and CSE.</p>

Correlation of methylation of CpG island in cystathionine beta synthase promoter and clinicopathological features in colorectal cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To explore the association between methylation of cystathionine-beta-synthase (CBS) promoter and clinicopathological features in colorectal cancer.</p><p><b>METHODS</b>Bisulfate sequencing PCR, real-time RT-PCR, and immunohistochemistry were used to investigate the methylation of CpG island in CBS promoter of 95 sporadic colorectal cancers. Software SPSS PASW Statistics was used to analyze the data of the hypermethylation levels in the malignant tissues and the correlation with pathological parameters and clinical outcome.</p><p><b>RESULTS</b>Methylation levels in tumor tissue of patients [(64.9 ± 14.3)%]with colorectal cancer were significantly higher than that in normal tissues[(27.5 ± 13.1)%, P < 0.001]. The CBS mRNA levels in the hypomethylation group (7.22 ± 1.91) were significantly higher than that in the hypermethylation group (2.78 ± 1.12, P < 0.01). Univariate analysis showed that age, pT stage, pN stage, liver metastases, pTNM stage, and CBS hypermethylation level significantly correlated with the survival and recurrence rates of colorectal cancer patients (All P < 0.05). Multivariate analysis showed that CBS hypermethylation level and liver metastasis were independent factors significantly correlated with the recurrence rate and overall survival of the patients (All P < 0.05).</p><p><b>CONCLUSIONS</b>Our study indicates that methylation of CpG island in CBS promoter is correlated with the occurrence and progression of colorectal cancer and plays a role in its tumorigenesis. It might serve as a useful marker for early diagnosis, targeted therapy and prediction of prognosis in colorectal cancer.</p>

Hydrogen sulfide and penile erection / 中华男科学杂志

Hydrogen sulfide (H2S) is the third type of active endogenous gaseous signal molecule following nitric oxide (NO) and carbon monoxide (CO). In mammalians, H2S is mainly synthesized by two proteases, cystathionine-beta-synthase (CBS) and cystathionine-gamma-lyase (CSE). H2S plays an essential function of physiological regulation in vivo, and promotes penile erection by acting on the ATP-sensitive potassium channels to relax the vascular smooth muscle as well as by the synergistic effect with testosterone and NO to relax the corpus cavernosum smooth muscle (CCSM). At present, the selective phosphodiesterase type 5 (PDE5) inhibitor is mainly used for the treatment of erectile dysfunction (ED), but some ED patients fail to respond. Therefore, further studies on the mechanism of H2S regulating penile erection may provide a new way for the management of erectile dysfunction.

Genetic variation in genes involved in folate and drug metabolism in a south Indian population.

BACKGROUND: Genetic variations represented as single nucleotide polymorphisms (SNPs) vary across the world population. This genetic polymorphism (such as SNPs) plays an important role in pharmacogenomics. SNPs that affects cellular metabolism, by altering the enzyme activity, have an important role in therapeutic outcome. Allele frequencies in number of clinically relevant SNPs within south Indian populations are not yet known. Hence, we genotyped randomly selected unrelated south Indian subjects from different locations of south India representing the heterogeneous ethnic background of the population. MATERIALS AND METHODS: Common variants of MTHFD1, TYMS, SHMT1, MTR, MTRR, CBS and SULT1A1 gene polymorphisms were screened from healthy unrelated south Indian volunteers. Genotypes were determined using RFLP analysis of polymerase chain reaction-amplified products and confirmed by DNA sequencing. Chi-square test was performed to test for deviation from the Hardy-Weinberg equilibrium for each locus. RESULTS: Gene allele frequency for several polymorphisms in our study differed significantly between the populations of other nations reported for several of the SNPs. These results demonstrate that the populations in different geographic regions may have widely varying genetic allele frequencies for clinically relevant SNPs. CONCLUSION: The present study reports, for the first time, the frequency distribution of MTHFD1, TYMS, SHMT1, MTR, MTRR, CBS and SULTIA1 gene polymorphisms in a south Indian population. Population-specific genetic polymorphism studies will help in practicing pharmacogenomic principles in the clinics.

Classical hemocystinuria in two Filipino patients

Classical hemocystinuria is an inborn error of metabolism caused by a deficiency of cystathionine beta-synthase that converts hemocysteine to cystathionine. This then leads to elevation of hemocysteine which results in abnormalities of the eyes, skeleton, central nervous system and vascular hemocystinuria. Patient 1 presented with lens dislocation and mental retardation while Patient 2 presented with thromboembolism, mental retardation and lens dislocation. The elevated plasma hemocysteine and methionine levels lead to the diagnosis of hemocystinuria.

Predictive role of cerebrospinal fluid hydrogen sulfide in central nervous system leukemia / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Central nervous system leukemia (CNSL) is an important relapse in children with acute lymphoblastic leukemia (ALL). We investigated the possible role of endogenous hydrogen sulfide (H(2)S) of cerebrospinal fluid (CSF) in predicting CNSL.</p><p><b>METHODS</b>From August 2008 to December 2010, 380 children were enrolled in this study at Shijitan Hospital, China. These children were from 2 to 16 years old, and the median age was 6.5 years. They were divided into a CNSL group (7 cases), a leukemia group (307 cases), a non-leukemia group (26 cases) and a healthy group (40 children). CSF specimens were obtained from conventional lumbar punctured, then centrifuged and supernatants preserved for H(2)S detection. Leukemic cells precipitates from CSF were found in three cases, the hCSE and hCBS mRNA expression was detected by reverse transcription polymerase chain reaction (RT-PCR), and H(2)S levels in serum were also measured. The receiver operating characteristic (ROC) curve and area under curve (AUC) were used to assess the predictive diagnosis role of CSF H(2)S in children with ALL and CNSL.</p><p><b>RESULTS</b>The serum H(2)S contents of the CNSL and leukemia groups were (96.98 ± 15.77) µmol/L and (93.35 ± 17.16) µmol/L respectively, much higher than those of healthy, (44.29 ± 2.15) µmol/L, and non-leukemia, (46.32 ± 6.54) µmol/L, groups (P < 0.01). Compared with the leukemia group, CSF H(2)S content of the CNSL group was significantly high (P < 0.01). Meanwhile, in contrast to the non-leukemia group, CSF H(2)S contents of the CNSL and leukemia groups were both significantly increased (P < 0.01). In addition, leukemic cells from CSF precipitations could express CBS and CSE mRNA. Furthermore, the ROC analysis showed the UAC was 0.929 (95%CI: 0.857 - 1.000), and the optimum cut-off value of CSF H(2)S was 12.08 µ mol/L, and the sensitivity and specificity were 83.3% and 97.2% respectively.</p><p><b>CONCLUSIONS</b>CSF H(2)S contents were significantly increased in children with CNSL. After treatment, H(2)S contents were decreased subsequently. Therefore, we speculated that H(2)S levels of CSF would predict CNSL in ALL children.</p>