A mechanism of retinal protection from light-induced degeneration by hydrogen sulfide.
A mechanism of retinal protection from light-induced degeneration by hydrogen sulfide.
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DOI：
10.4161/cib.18679
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发表时间：
2012-03-01
影响因子：
--
通讯作者：
Kimura H
中科院分区：
文献类型：
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作者：
Mikami Y;Kimura H
自从我们最初证明硫化氢 (H2S) 可能充当大脑中的神经调节剂和血管系统中的平滑肌松弛剂以来，越来越多的证据表明 H2S 可能充当信号分子。我们和其他人还发现H2S具有细胞保护作用。由于 H2S 是众所周知的有毒气体，因此其细胞保护作用一直被忽视。 H2S 保护神经元免受氧化应激。它还可以保护心肌免受缺血再灌注损伤。这一发现促使H2S应用于搭桥手术患者的II期临床试验。胱硫醚β-合酶(CBS) 和胱硫醚γ-裂解酶(CSE) 是众所周知的H2S 产生酶。我们最近证明，另一种产生 H2S 的酶，3-巯基丙酮酸硫转移酶 (3MST) 和半胱氨酸转氨酶 (CAT) 定位于大脑中的神经元和血管内皮。然而，3MST/CAT 途径对 H2S 产生的调节尚不清楚。本研究表明，3MST/CAT 途径产生的 H2S 受 Ca2+ 调节，并且 H2S 通过抑制强光引起的过量 Ca2+ 流入，保护视网膜感光细胞免受光诱导的变性。
Since our initial demonstrations that hydrogen sulfide (H2S) may function as a neuromodulator in the brain and a smooth muscle relaxant in the vascular system, accumulating evidence shows that H2S may function as a signaling molecule. We and others also found that H2S has a cytoprotective effect. Because H2S is well-known toxic gas, a cytoprotective role has been overlooked. H2S protects neurons from oxidative stress. It also protects cardiac muscle from ischemia-reperfusion injury. The finding led to the application of H2S to the bypass surgery patients in Phase II clinical trial. Cystathionine β–synthase (CBS) and cystathionine γ–lyase (CSE) are well known as H2S-producing enzymes. We recently demonstrated that the other H2S-producing enzyme, 3-mercaptopyruvate sulfurtransferase (3MST) along with cysteine aminotransferase (CAT) is localized to neurons in the brain and to the vascular endothelium. However, the regulation of H2S production by 3MST/CAT pathway had not been well understood. The present study shows that H2S production by 3MST/CAT pathway is regulated by Ca2+ and that H2S protects retinal photoreceptor cells from light induced degeneration by suppressing excessive Ca2+ influx caused by intense light.