Department of Hepatobiliary Surgery, Fuzong Clinical Medical College of Fujian Medical University, Fuzhou, Fujian 350001, P.R. China.
Department of Hepatobiliary Surgery, 900 Hospital of The Joint Logistics Team, Fuzhou, Fujian 350025, P.R. China.
Mol Med Rep. 2019 Nov;20(5):4003-4012. doi: 10.3892/mmr.2019.10645. Epub 2019 Sep 3.
Liver ischemia‑reperfusion (I/R) injury is an important clinical issue related to liver transplantation. Recent studies suggest that microRNAs are implicated in various biological and pathological processes, including liver I/R injury. This study aimed to investigate the role and potential mechanism of miR‑27a during liver I/R injury. A liver I/R model was induced via 60 min of ischemia and reperfusion for 6 h in rats. Cells were transfected with miR‑27a mimics or the miR‑27a inhibitor to examine the effect of miR‑27a on liver I/R. Apoptotic cells were detected by flow cytometry and TUNEL staining. The expression of miR‑27a was measured by real‑time PCR. The expression of peroxisome proliferator‑activated receptor γ (PPARγ); gastrin‑releasing peptide 78 (GRP78) and C/EBP homologous protein (CHOP) were detected by western blot analysis. The results showed that miR‑27a was significantly upregulated during I/R injury in vivo and in vitro. In addition, miR‑27a inhibitors attenuated hypoxia/reoxygenation (H/R)‑induced oxidative stress, endoplasmic reticulum stress (ERS) and apoptosis in AML12 cells. By contrast, miR‑27a mimics promoted hypoxia/reoxygenation‑induced ERS, and apoptosis. Furthermore, PPARγ was identified as a target gene of miR‑27a using bioinformatic analysis and a dual‑luciferase reporter assay. Knockdown of PPARγ significantly abrogated the inhibitory effect of miR‑27a inhibitors on the ERS pathway. Moreover, the miR‑27a antagomir attenuated liver I/R injury in rats, a finding manifested by reduced ALT/AST, hepatocyte apoptosis, oxidative stress and inhibition of the ERS pathway. Taken together, these findings demonstrate that suppression of miR‑27a protects against liver I/R injury by targeting PPARγ and by inhibiting the ERS pathway.
肝缺血再灌注（I/R）损伤是与肝移植相关的一个重要临床问题。最近的研究表明，miRNAs 参与了多种生物学和病理学过程，包括肝 I/R 损伤。本研究旨在探讨 miR-27a 在肝 I/R 损伤中的作用及潜在机制。通过在大鼠中诱导 60 分钟缺血和 6 小时再灌注来建立肝 I/R 模型。用 miR-27a 模拟物或 miR-27a 抑制剂转染细胞，以观察 miR-27a 对肝 I/R 的影响。通过流式细胞术和 TUNEL 染色检测凋亡细胞。实时 PCR 检测 miR-27a 的表达。Western blot 分析检测过氧化物酶体增殖物激活受体 γ（PPARγ）、胃泌素释放肽 78（GRP78）和 C/EBP 同源蛋白（CHOP）的表达。结果表明，miR-27a 在体内和体外 I/R 损伤中显著上调。此外，miR-27a 抑制剂减弱了 AML12 细胞缺氧/复氧（H/R）诱导的氧化应激、内质网应激（ERS）和细胞凋亡。相反，miR-27a 模拟物促进了 H/R 诱导的 ERS 和细胞凋亡。此外，通过生物信息学分析和双荧光素酶报告基因检测，发现 PPARγ 是 miR-27a 的靶基因。PPARγ 敲低显著减弱了 miR-27a 抑制剂对 ERS 途径的抑制作用。此外，miR-27a 拮抗剂减轻了大鼠肝 I/R 损伤，表现为 ALT/AST 降低、肝细胞凋亡减少、氧化应激减轻和 ERS 途径抑制。综上所述，这些发现表明，抑制 miR-27a 通过靶向 PPARγ 并抑制 ERS 途径来保护肝免受 I/R 损伤。
