Hydrogen sulfide inhibits nitric oxide production and nuclear factor-κB via heme oxygenase-1 expression in RAW264.7 macrophages stimulated with lipopolysaccharide
Hydrogen sulfide inhibits nitric oxide production and nuclear factor-κB via heme oxygenase-1 expression in RAW264.7 macrophages stimulated with lipopolysaccharide
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DOI：
10.1016/j.freeradbiomed.2006.03.021
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发表时间：
2006-07-01
影响因子：
7.4
通讯作者：
Chung, Hun-Taeg
中科院分区：
文献类型：
--
作者：
Oh, Gi-Su;Pae, Hyun-Ock;Chung, Hun-Taeg
硫化氢（H2S）是一种由胱硫醚γ-裂解酶（CSE）和/或胱硫醚β-合酶（CBS）从L-半胱氨酸（L-Cys）代谢内源性合成的调节性气体分子，是一种假定的血管扩张剂，并且其在一氧化氮（NO）产生中的作用尚未探索。在这里，我们表明，在非细胞毒性浓度下，H2S能够抑制NO的产生和诱导型NO合酶（iNOS）的表达，通过血红素加氧酶（HO-1）的表达与脂多糖（LPS）刺激的RAW 264.7巨噬细胞。通过鼓泡纯H2S气体制备的H2S溶液和H2S供体NaSH均通过激活细胞外信号调节激酶（ERK）诱导HO-1表达，并呈剂量依赖性。H2S或NaHS预处理显著抑制LPS诱导的iNOS表达和NO产生。此外，在LPS刺激的巨噬细胞中表达CSE mRNA的NO产生通过添加L-Cys（H2S的底物）而显著降低，但通过选择性CSE抑制剂β-氰基-L-丙氨酸而不是CBS抑制剂氨氧基乙酸而增强。HO抑制剂锡原卟啉IX阻断HO活性或HO-1小干扰RNA（siRNA）下调HO-1表达均可逆转H2S对iNOS表达和NO产生的抑制作用，而HO-1过表达则产生与H2S相同的抑制作用。此外，LPS诱导的核因子（NF）-κ B B活化减少与硫化氢预孵育的RAW 264.7巨噬细胞。有趣的是，H2S对NF-κ B活化的抑制作用被HO-1 siRNA瞬时转染逆转，但被HO-1基因转染或HO-1终产物一氧化碳（CO）处理模拟。CO处理还通过灭活NF-κ B来抑制LPS诱导的NO产生和iNOS表达。总的来说，我们的研究结果表明，H2S可以通过涉及HO-1/CO作用的机制抑制LPS刺激的巨噬细胞中NO的产生和NF-κ B活化。All rights reserved.
Hydrogen sulfide (H2S), a regulatory gaseous molecule that is endogenously synthesized by cystathionine gamma-lyase (CSE) and/or cystathionine beta-synthase (CBS) from L-cysteine (L-Cys) metabolism, is a putative vasodilator, and its role in nitric oxide (NO) production is unexplored. Here, we show that at noncytotoxic concentrations, H2S was able to inhibit NO production and inducible NO synthase (iNOS) expression via heme oxygenase (HO-1) expression in RAW264.7 macrophages stimulated with lipopolysaccharide (LPS). Both H2S solution prepared by bubbling pure H2S gas and NaSH, a H2S donor, dose dependently induced HO-1 expression through the activation of the extracellular signal-regulated kinase (ERK). Pretreatment with H2S or NaHS significantly inhibited LPS-induced iNOS expression and NO production. Moreover, NO production in LPS-stimulated macrophages that are expressing CSE mRNA was significantly reduced by the addition of L-Cys, a substrate for H2S, but enhanced by the selective CSE inhibitor beta-cyano-L-alanine but not by the CBS inhibitor aminooxyacetic acid. While either blockage of HO activity by the HO inhibitor, tin protoporphyrin IX, or down-regulation of HO-1 expression by HO-1 small interfering RNA (siRNA) reversed the inhibitory effects of H2S on iNOS expression and NO production, HO-1 overexpression produced the same inhibitory effects of H2S. In addition, LPS-induced nuclear factor (NF)-kappa B activation was diminished in RAW264.7 macrophages preincubated with H2S. Interestingly, the inhibitory effect of H2S on NF-kappa B activation was reversed by the transient transfection with HO-1 siRNA, but was mimicked by either HO-1 gene transfection or treatment with carbon monoxide (CO), an end product of HO-1. CO treatment also inhibited LPS-induced NO production and iNOS expression via its inactivation of NF-kappa B. Collectively, our results suggest that H2S can inhibit NO production and NF-kappa B activation in LPS-stimulated macrophages through a mechanism that involves the action of HO-1/CO. (c) 2006 Elsevier Inc. All rights reserved.