National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan.
Antioxid Redox Signal. 2012 Jul 1;17(1):45-57. doi: 10.1089/ars.2011.4345. Epub 2012 Mar 2.
Accumulating evidence shows that hydrogen sulfide may function as a signaling molecule in processes such as neuromodulation in the brain and smooth muscle relaxation in the vascular system. It also has a cytoprotective effect, since it can protect neurons and cardiac muscle from oxidative stress and ischemia-reperfusion injury, respectively. Hydrogen sulfide can also modulate inflammation, insulin release, and angiogenesis.
The regulation of the activity of 3-mercaptopyruvate sulfur transferase (3MST) along with cysteine aminotransferase (CAT), one of the H(2)S producing pathways, has been demonstrated. The production of H(2)S by the pathway, which is regulated by Ca(2+) and facilitated by thioredoxin and dihydrolipoic acid, is also involved in H(2)S signaling as well as cytoprotection. Sulfur hydration of proteins by H(2)S has been proposed to modulate protein functions. H(2)S-sensitive fluorescent probes, which enable us to measure the localization of H(2)S in real time, have been developed.
The basal concentrations of H(2)S have recently been measured and found to be much lower than those initially reported. However, the concentration of H(2)S reached in stimulated cells, as well as the regulation of H(2)S producing enzymes is not well understood. It has been proposed that some of the effects of H(2)S on the regulation of enzymes and receptors might be explained through the properties of sulfane sulfur (S(0)), another form of active sulfur.
The determination of H(2)S concentrations in activated cells using new methods including H(2)S-sensitive fluorescent probes, as well as the investigation of the effects of H(2)S using specific inhibitors, may provide better understanding of the physiological function of this molecule. Clarifying mechanisms of H(2)S activity may also facilitate the development of new therapeutic compounds.
越来越多的证据表明，硫化氢可能在大脑中的神经调节和血管系统中的平滑肌松弛等过程中发挥信号分子的作用。它还具有细胞保护作用，因为它可以分别保护神经元和心肌免受氧化应激和缺血再灌注损伤。硫化氢还可以调节炎症、胰岛素释放和血管生成。
已经证明了 3-巯基丙酮酸硫转移酶（3MST）和半胱氨酸氨基转移酶（CAT）的活性调节，这是产生 H2S 的途径之一。该途径产生的 H2S 通过 Ca2+ 调节，并通过硫氧还蛋白和二氢硫辛酸促进，也参与 H2S 信号传递和细胞保护。H2S 通过蛋白质的硫水合作用来调节蛋白质的功能。已经开发出 H2S 敏感荧光探针，使我们能够实时测量 H2S 的定位。
最近测量了 H2S 的基础浓度，发现远低于最初报道的浓度。然而，刺激细胞中 H2S 的浓度以及 H2S 产生酶的调节还不是很清楚。有人提出，H2S 对酶和受体调节的一些影响可能可以通过另一种形式的活性硫——亚硫酸硫（S(0)）的性质来解释。
使用新方法（包括 H2S 敏感荧光探针）测定激活细胞中的 H2S 浓度，并使用特定抑制剂研究 H2S 的作用，可能会更好地理解该分子的生理功能。阐明 H2S 活性的机制也可能有助于开发新的治疗化合物。
