Animals ; Humans ; Hydrogen Sulfide ; metabolism ; Inflammation ; metabolism

OBJECTIVETo review the vasorelaxant effects of hydrogen sulfide (H(2)S) in arterial rings in the cardiovascular system under both physiological and pathophysiological conditions and the possible mechanisms involved.

DATA SOURCESThe data in this review were obtained from Medline and Pubmed sources from 1997 to 2011 using the search terms "hydrogen sulfide" and "vascular relaxation".

STUDY SELECTIONArticles describing the role of hydrogen sulfide in the regulation of vascular activity and its vasorelaxant effects were selected.

RESULTSH(2)S plays an important role in the regulation of cardiovascular tone. The vasomodulatory effects of H(2)S depend on factors including concentration, species and tissue type. The H(2)S donor, sodium hydrosulfide (NaHS), causes vasorelaxation of rat isolated aortic rings in a dose-dependent manner. This effect was more pronounced than that observed in pulmonary arterial rings. The expression of K(ATP) channel proteins and mRNA in the aortic rings was increased compared with pulmonary artery rings. H(2)S is involved in the pathogenesis of a variety of cardiovascular diseases. Downregulation of the endogenous H(2)S pathway is an important factor in the pathogenesis of cardiovascular diseases. The vasorelaxant effects of H(2)S have been shown to be mediated by activation of K(ATP) channels in vascular smooth muscle cells and via the induction of acidification due to activation of the Cl(-)/HCO(3)(-) exchanger. It is speculated that the mechanisms underlying the vasoconstrictive function of H(2)S in the aortic rings involves decreased NO production and inhibition of cAMP accumulation.

CONCLUSIONH(2)S is an important endogenous gasotransmitter in the cardiovascular system and acts as a modulator of vascular tone in the homeostatic regulation of blood pressure.

Animals ; Cardiovascular System ; metabolism ; Humans ; Hydrogen Sulfide ; metabolism ; Vasodilation ; physiology

OBJECTIVEThis review discusses the current status and progress in studies on the roles of hydrogen sulfide (H(2)S) in regulation of neurotoxicity, neuroprotection, and neuromodulator, as well as its therapeutic potential for neurodegenerative disorders.

DATA SOURCESThe data used in this review were mainly from Medline and PubMed published in English from 2001 to August 2011. The search terms were "hydrogen sulfide", "neuron", and "neurodegenerative disorders".

STUDY SELECTIONArticles regarding the regulation of neuronal function, the protection against neuronal damage and neurological diseases, and their possible cellular and molecular mechanisms associated with H(2)S were selected.

RESULTSThe inhibited generation of endogenous H(2)S is implicated in 1-methy-4-phenylpyridinium ion, 6-OHDA, and homocysteine-triggered neurotoxicity. H(2)S elicits neuroprotection in Alzheimer's disease and Parkinson's disease models as well as protecting neurons against oxidative stress, ischemia, and hypoxia-induced neuronal death. H(2)S offers anti-oxidant, anti-inflammatory and anti-apoptotic effects, as well as activates ATP-sensitive potassium channels and cystic fibrosis transmembrane conductance regulator Cl- channels. H(2)S regulates the long-term potentiation (LTP) and GABAB receptors in the hippocampus, as well as intracellular calcium and pH homeostasis in neurons and glia cells.

CONCLUSIONSThese articles suggest that endogenous H(2)S may regulate the toxicity of neurotoxin. H(2)S not only acts as a neuroprotectant but also serves as a novel neuromodulator.

Animals ; Humans ; Hydrogen Sulfide ; metabolism ; Nervous System ; metabolism ; Neuroprotective Agents ; metabolism ; Neurotoxins ; metabolism ; Neurotransmitter Agents ; metabolism

OBJECTIVE: To study the change of endogenous hydrogen sulfide (hydrogen sulfide, H2S) and its rate-limiting enzyme Cystathionine-gamma-lyase (CSE) in allergic rhinitis through guinea pigs with intervention treatment. METHOD: Twenty-four guinea pigs were divide into 4 groups at random, one group were models of allergic rhinitis (AR) which were established by using ovalbumin, the second group were treated with NaHS after sensitized, the third group were treated with Propargylglycine (PPG) which was suppression of CSE after sensitized, and the last group were treated with saline for control. The concentration of eotaxin of nasal lavage and H2S in plasma were recorded, and then the expression of CSE in nasal mucosa was determined by real-time fluorescence RT-PCR. RESULT: The concentration of eotaxin in nasal lavage of sensitized group were higher than those of control (P < 0.01), and concentration of H2S in plasma and expression of CSE in nasal mucosa were lower than control (P < 0.05). The concentration of eotaxin decreased when treated with NaHS and increased when treated with PGG (P < 0.05). Level of H2S in plasma and expression of CSE increased when treated with NaHS and decreased when treated with PGG (P < 0.05), and the level of H2S was positive linear correlate with the expression of CSE. CONCLUSION Endogenous H2S perhaps plays a significant role in the pathogenesis of allergic rhinitis, and it was mainly regulated by CSE.
Animals ; Cystathionine gamma-Lyase ; metabolism ; Guinea Pigs ; Hydrogen Sulfide ; metabolism ; Male ; Nasal Mucosa ; metabolism ; Rhinitis ; metabolism

BACKGROUNDHypertension is a common disease of the cardiovascular system. So far, the pathogenesis of primary hypertension remains unclear. The elaboration of its pathogenesis is an important topic in the field which calls for urgent resolution. The aim of this study was to probe into the metabolic imbalance of homocysteine (Hcy) and hydrogen sulfide (H(2)S) in children with essential hypertension, and its significance in the pathogenesis of essential hypertension.

METHODSTwenty-five children with essential hypertension and 30 healthy children with normal blood pressure were enrolled in the study. The medical history was investigated and a physical examination was conducted on the subjects. Plasma Hcy content was examined by fluorescence polarization immunoassay (FPIA). The plasma H(2)S level was detected by a modified method with a sulfide electrode. Data were presented as mean +/- standard deviation. The t test was applied to the mean values of both groups. Pearson linear correlation analysis was applied to the plasma Hcy and H(2)S as well as to the systolic pressure against the plasma H(2)S/Hcy ratio.

RESULTSPlasma Hcy, an intermittent metabolite of the endogenous methionine pathway, was markedly increased but plasma H(2)S, a final product of this pathway was significantly decreased in hypertensive cases when compared with normal subjects ((Hcy: (12.68 +/- 9.69) micromol/L vs (6.62 +/- 4.79) micromol/L (t = 2.996, P < 0.01); H(2)S: (51.93 +/- 6.01) micromol/L vs (65.70 +/- 5.50) micromol/L) (t = -8.670, P < 0.01)). The ratio of plasma H(2)S/Hcy in children with hypertension was 5.83 +/- 2.91, while that of the control group was 11.60 +/- 3.30, and the difference is significant with a t = -6.610 and P < 0.01. A negative correlation existed between plasma Hcy and H(2)S concentrations, r = -0.379, P < 0.05. And a negative correlation was found between systolic blood pressure and the plasma H(2)S/Hcy ratio, r = -0.687, P < 0.05.

CONCLUSIONThere was a metabolic imbalance of homocysteine and hydrogen sulfide in essential hypertensive children.

Adolescent ; Child ; Female ; Homocysteine ; metabolism ; Humans ; Hydrogen Sulfide ; metabolism ; Hypertension ; etiology ; metabolism ; physiopathology ; Male ; Systole

Animals ; Cardiovascular Diseases ; metabolism ; Humans ; Hydrogen Sulfide ; metabolism ; Hypertension ; metabolism ; Signal Transduction ; physiology

"Qi" and "blood" are two essential concepts in Chinese medicine (CM). As qi is intangible, the concept of qi is still controversial between CM and Western medicine. However, the endogenous hydrogen sulfide (H2S) and other gaseous signaling molecules provides a new approach for understanding the essence of qi in CM. Blood stasis syndrome is a common syndrome in CM. According to the CM theory, the incidence of blood stasis syndrome is closely correlated to the reckless movement of qi, as qi and blood are inseparable in regulating physiological functions. In recent years, more and more evidences suggest a close correlation between blood stasis syndrome and microcirculation dysfunction. In this paper, we discuss the relationship between endogenous H2S and blood stasis syndrome based on qi-blood theory of CM. We found that endogenous H2S maybe a material basis in concept of qi in CM, while dysfunctional microcirculation is the pathological basis of the blood stasis syndrome. As qi is closely associated with incidence and progression of blood stasis syndrome, endogenous H2S may play an important role in preventing and treating the blood stasis syndrome by improving the function of microcirculation.
Blood ; metabolism ; Humans ; Hydrogen Sulfide ; metabolism ; Medicine, Chinese Traditional ; Microcirculation ; Qi ; Syndrome

Animals ; Hydrogen Sulfide ; metabolism ; Hypertension, Portal ; metabolism ; physiopathology ; Male ; Rats ; Rats, Sprague-Dawley

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.
Cystathionine beta-Synthase ; metabolism ; Cystathionine gamma-Lyase ; metabolism ; Humans ; Hydrogen Sulfide ; Male ; Penile Erection

Vascular calcification is a common pathological process in patients with diabetes, chronic kidney disease, and cardiovascular disease, manifested by the deposition of hydroxyapatite on the walls of blood vessels. Hydrogen sulfide is the third gas signal molecule found in mammals after nitric oxide and carbon monoxide, which has anti-inflammatory, antioxidant stress and other effects in the cardiovascular system. In recent years, it has been recognized that hydrogen sulfide has an anti-vascular calcification effect, and supplementation with hydrogen sulfide and its donors can alleviate vascular calcification. In this review, we discussed the various evidence of the protective effect of hydrogen sulfide on vascular calcification, and highlighted the hydrogen sulfide metabolism changes and the potential regulatory mechanisms of hydrogen sulfide on the pathophysiological changes in vascular calcification.
Animals ; Humans ; Hydrogen Sulfide/metabolism* ; Cardiovascular Diseases ; Carbon Monoxide ; Antioxidants ; Nitric Oxide ; Mammals/metabolism*