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目的:探讨核因子E2相关因子2（Nrf2）蛋白对小鼠脓毒症相关性肝损伤（SALI）铁死亡的作用。方法:按随机数字表法将雄性SD小鼠分成6组，每组6只。采用盲肠结扎穿孔术（CLP）构建小鼠SALI模型，假手术（Sham）组仅开腹处理。CLP+Fer-1组、CLP+Erastin组、CLP+ML385组、CLP+Curcumin组分别于术后经腹腔注射铁死亡抑制剂Ferrostatin-1（Fer-1）10 mg·kg -1·d -1、铁死亡激活剂Erastin 20 mg·kg -1·d -1、Nrf2抑制剂ML385 30 mg·kg -1·d -1、Nrf2激活剂Curcumin 100 mg·kg -1·d -1进行干预；Sham组、CLP组予生理盐水10 mg·kg -1·d -1，均连续给药10 d。术后10 d收集小鼠血清和肝组织，检测血清丙氨酸转氨酶（ALT）、天冬氨酸转氨酶（AST），以及肝组织匀浆液中丙二醛（MDA）、谷胱甘肽（GSH）和Fe 2+水平；苏木素-伊红（HE）染色后光镜下观察肝组织病理学改变；透射电镜下观察肝细胞线粒体形状和长度；蛋白质免疫印迹试验（Western blotting）检测肝组织Nrf2、谷胱甘肽过氧化物酶4（GPX4）、前列腺素-内过氧化物合酶2（PTGS2）的蛋白表达。 结果:与Sham组比较，CLP组小鼠血清ALT、AST水平明显升高；镜下可见肝索排列紊乱，细胞肿胀、坏死，线粒体长度明显变短；肝组织中MDA、Fe 2+水平明显上升，GSH含量明显下降，Nrf2、GPX4蛋白表达下降，PTGS2蛋白表达明显升高。与CLP组比较，CLP+Fer-1组和CLP+Curcumin组血清ALT、AST水平明显降低〔ALT（U/L）：80.65±19.44、103.45±20.52比283.50±37.12，AST（U/L）：103.33±11.90、127.33±15.79比288.67±36.82，均 P<0.05〕；镜下可见肝索欠规整，细胞轻微肿胀，线粒体长度明显增加（μm：1.42±0.09、1.43±0.21比1.07±0.25，均 P<0.05）；肝组织中MDA、Fe 2+水平明显下降，GSH含量明显升高〔MDA（mol/g）：0.87±0.23、1.85±0.43比4.47±0.95，Fe 2+（μg/g）：63.80±7.15、67.48±6.28比134.52±14.32，GSH（mol/g）：1.95±0.29、1.95±0.45比0.55±0.29，均 P<0.05〕；肝组织Nrf2、GPX4蛋白表达明显升高，PTGS2蛋白表达明显下降（Nrf2/GAPDH：1.80±0.28、2.10±0.43比0.70±0.24，GPX4/GAPDH：0.80±0.06、0.93±0.07比0.48±0.02，PTGS2/GAPDH：0.76±0.05、0.84±0.01比1.02±0.09，均 P<0.05）；而CLP+Erastin组、CLP+ML385组上述指标结果则相反，血清ALT、AST水平明显升高〔ALT（U/L）：344.52±40.79、321.70±21.10比283.50±37.12，AST（U/L）：333.50±27.90、333.00±16.67比288.67±36.82，均 P<0.05〕；镜下可见肝索排列紊乱，细胞明显肿胀、坏死，线粒体长度明显变短（μm：0.78±0.13、0.67±0.07比1.07±0.25，均 P<0.05）；肝组织中MDA、Fe 2+水平明显升高，GSH含量明显下降〔MDA（mol/g）：5.92±1.06、5.62±0.56比4.47±0.95，Fe 2+（μg/g）：151.40±8.03、151.88±8.68比134.52±14.32，GSH（mol/g）：0.25±0.08和0.23±0.11比0.55±0.29，均 P<0.05〕；肝组织Nrf2、GPX4蛋白表达明显下降，PTGS2蛋白表达明显升高（Nrf2/GAPDH：0.46±0.09、0.46±0.11比0.70±0.24，GPX4/GAPDH：0.34±0.05、0.40±0.01比0.48±0.02，PTGS2/GAPDH：1.24±0.13、1.16±0.11比1.02±0.09，均 P<0.05）。 结论:CLP诱导的SALI可导致小鼠肝细胞铁死亡，肝组织Nrf2蛋白可通过调节铁死亡介导SALI。

Objective:To investigate the effect of nuclear factor E2-related factor 2 (Nrf2) protein on ferroptosis in mice with sepsis-associated liver injury (SALI).Methods:The male Sprague-Dawley (SD) mice were divided into 6 groups according to the random number table method, with 6 mice in each group. The SALI model of mice was established by cecal ligation and puncture (CLP), and the Sham group was only treated with laparotomy. CLP+Fer-1 group, CLP+Erastin group, CLP+ML385 group and CLP+Curcumin group were intraperitoneally injected with iron death inhibitor Ferrostatin-1 (Fer-1) 10 mg·kg -1·d -1, iron death activator Erastin 20 mg·kg -1·d -1, Nrf2 inhibitor ML385 30 mg·kg -1·d -1 and Nrf2 activator Curcumin 100 mg·kg -1·d -1 after CLP, respectively; Sham group and CLP group were given normal saline 10 mg·kg -1·d -1, each group was administered continuously for 10 days. Ten days after operation, the serum and liver tissues of mice were collected to detect the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum, and the levels of malondialdehyde (MDA), glutathione (GSH) and Fe 2+ in liver homogenate. The pathological changes of liver tissue were observed under light microscope after hematoxylin-eosin (HE) staining. The shape and length of mitochondria in liver cells were observed under transmission electron microscope. The protein expressions of Nrf2, glutathione peroxidase 4 (GPX4) and prostaglandin-endoperoxide synthase 2 (PTGS2) in liver tissue were detected by Western blotting. Results:Compared with Sham group, the serum levels of ALT and AST in the CLP group were significantly increased; histologically, the hepatic cord was disordered, the cells were swollen and necrotic, and the length of mitochondria was significantly shortened; the levels of MDA and Fe 2+ in liver tissue increased significantly, and the content of GSH decreased significantly; the protein expressions of Nrf2 and GPX4 in liver tissue decreased, and the protein expression of PTGS2 increased significantly. Compared with CLP group, the serum levels of ALT and AST in CLP+Fer-1 group and CLP+Curcumin group were significantly decreased [ALT (U/L): 80.65±19.44, 103.45±20.52 vs. 283.50±37.12, AST (U/L): 103.33±11.90, 127.33±15.79 vs. 288.67±36.82, all P < 0.05]; microscopically, the hepatic cord was irregular, the cells were slightly swollen, and the mitochondrial length was significantly increased (μm: 1.42±0.09, 1.43±0.21 vs. 1.07±0.25, both P < 0.05); the levels of MDA and Fe 2+ in liver tissue decreased significantly, and the content of GSH increased significantly [MDA (mol/g): 0.87±0.23, 1.85±0.43 vs. 4.47±0.95, Fe 2+ (μg/g): 63.80±7.15, 67.48±6.28 vs. 134.52±14.32, GSH (mol/g): 1.95±0.29, 1.95±0.45 vs. 0.55±0.29, all P < 0.05]; the protein expressions of Nrf2 and GPX4 in liver tissue were significantly increased, and the protein expression of PTGS2 was significantly decreased (Nrf2/GAPDH: 1.80±0.28, 2.10±0.43 vs. 0.70±0.24, GPX4/GAPDH: 0.80±0.06, 0.93±0.07 vs. 0.48±0.02, PTGS2/GAPDH: 0.76±0.05, 0.84±0.01 vs. 1.02±0.09, all P < 0.05). However, the results of the above indexes in the CLP+Erastin group and CLP+ML385 group were opposite, and the serum levels of ALT and AST were significantly increased [ALT (U/L): 344.52±40.79, 321.70±21.10 vs. 283.50±37.12, AST (U/L): 333.50±27.90, 333.00±16.67 vs. 288.67±36.82, all P < 0.05]; microscopically, the arrangement of hepatic cords was disordered, the cells were obviously swollen and necrotic, and the length of mitochondria was significantly shortened (μm: 0.78±0.13, 0.67±0.07 vs. 1.07±0.25, both P < 0.05); the levels of MDA and Fe 2+ in liver tissue increased significantly, and the content of GSH decreased significantly [MDA (mol/g): 5.92±1.06, 5.62±0.56 vs. 4.47±0.95, Fe 2+ (μg/g): 151.40±8.03, 151.88±8.68 vs. 134.52±14.32, GSH (mol/g): 0.25±0.08, 0.23±0.11 vs. 0.55±0.29, all P < 0.05]; the protein expressions of Nrf2 and GPX4 in liver tissue were significantly decreased, and the protein expression of PTGS2 was significantly increased (Nrf2/GAPDH: 0.46±0.09, 0.46±0.11 vs. 0.70±0.24, GPX4/GAPDH: 0.34±0.05, 0.40±0.01 vs. 0.48±0.02, PTGS2/GAPDH: 1.24±0.13, 1.16±0.11 vs. 1.02±0.09, all P < 0.05). Conclusion:CLP-induced SALI can lead to ferroptosis in mice hepatocytes, and Nrf2 protein in liver tissue can mediate SALI by regulating ferroptosis.