Younis Nahla N, Shaheen Mohamed A, Mahmoud Mona F
Department of Biochemistry, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt.
Department of Histology and Cell Biology, Faculty of Medicine, Zagazig University, Zagazig, Egypt.
J Surg Res. 2016 Aug;204(2):398-409. doi: 10.1016/j.jss.2016.04.069. Epub 2016 May 24.
Hydrogen sulfide (H2S) can protect against hepatic ischemia-reperfusion injury (HIR). However, it is unknown whether it can protect against HIR in insulin resistance. This study investigated the protective effects of silymarin against HIR in a rat model of insulin resistance and the possible involvement of endogenous H2S.
Insulin resistance was first established using 10% fructose in drinking water for 10 weeks. HIR was conducted in fructose-fed rats treated with saline or silymarin (100 mg/kg), 15 min before HIR (30 min ischemia, followed by 1 h reperfusion). Insulin resistance and serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10), total nitrites (NO2(-)), and H2S were measured. Hepatic malondialdehyde (MDA), reduced glutathione (GSH), hydroxyproline, H2S synthesizing activity, and mRNA expression of cystathionine β-synthase (CBS) or cystathionine γ-lyase (CSE) were determined. Additionally, histopathological examination involved H&E, Sirius red, and caspase-3 immunostaining.
Fructose-induced insulin resistance increased serum ALT, TNF-α, H2S and H2S synthesizing activity, and hepatic MDA, hydroxyproline, and CSE mRNA and decreased NO2(-) and GSH. These changes exacerbated the HIR injury in which endogenous H2S production was auxiliary increased. Silymarin preconditioning decreased ALT, AST, MDA, NO2(-), TNF-α, and TNF-α/IL-10 ratio, increased GSH, IL-10, improved hepatic architecture, and lowered caspase-3 immunostaining. Serum H2S, its hepatic synthesizing activity, and CSE and CBS mRNA expressions were all suppressed by silymarin pretreatment.
The increases in endogenous H2S exacerbate HIR injury, whereas silymarin preconditioning protected against HIR in insulin resistant rats via powerful antioxidant, anti-inflammatory, and antiapoptotic effects along with suppressing H2S production.
硫化氢（H2S）可预防肝缺血再灌注损伤（HIR）。然而，其是否能在胰岛素抵抗状态下预防HIR尚不清楚。本研究调查了水飞蓟宾对胰岛素抵抗大鼠模型中HIR的保护作用以及内源性H2S可能参与的情况。
首先通过在饮水中添加10%果糖持续10周建立胰岛素抵抗模型。在缺血再灌注前15分钟，对喂食果糖的大鼠给予生理盐水或水飞蓟宾（100mg/kg）处理后进行HIR（30分钟缺血，随后1小时再灌注）。检测胰岛素抵抗、血清丙氨酸转氨酶（ALT）、天冬氨酸转氨酶（AST）、肿瘤坏死因子-α（TNF-α）、白细胞介素-10（IL-10）、总亚硝酸盐（NO2(-)）和H2S水平。测定肝脏丙二醛（MDA）、还原型谷胱甘肽（GSH）、羟脯氨酸、H2S合成活性以及胱硫醚β-合酶（CBS）或胱硫醚γ-裂解酶（CSE）的mRNA表达。此外，组织病理学检查包括苏木精-伊红染色、天狼星红染色和半胱天冬酶-3免疫染色。
果糖诱导的胰岛素抵抗使血清ALT、TNF-α、H2S及H2S合成活性、肝脏MDA、羟脯氨酸及CSE mRNA升高，使NO2(-)和GSH降低。这些变化加剧了HIR损伤，其中内源性H2S产生辅助性增加。水飞蓟宾预处理降低了ALT、AST、MDA、NO2(-)、TNF-α及TNF-α/IL-10比值，增加了GSH、IL-10，改善了肝脏结构，并降低了半胱天冬酶-3免疫染色。水飞蓟宾预处理抑制了血清H2S、其肝脏合成活性以及CSE和CBS mRNA表达。
内源性H2S增加会加剧HIR损伤，而水飞蓟宾预处理通过强大的抗氧化、抗炎和抗凋亡作用以及抑制H2S产生，对胰岛素抵抗大鼠的HIR起到保护作用。
