Genipin protects the liver from ischemia/reperfusion injury by modulating mitochondrial quality control
Hepatic ischemia and reperfusion (IR) injury is closely linked to oxidative mitochondrial damage. Since mitochondrial quality control (QC) plays a pivotal role in the recovery of impaired mitochondrial function, mitochondrial QC has emerged as a potential therapeutic target. Genipin, an iridoid compound from Gardenia jasminoides, has been showed antioxidant and anti-inflammatory properties. In this study, we investigated the hepatoprotective mechanism of genipin against IR-induced hepatic injury, particularly focusing on mitochondrial QC. Male C57BL/6 mice underwent liver ischemia for 60 min, followed by reperfusion for 6 h. Genipin (100 mg/kg, i.p.) or vehicle (10% Tween 80 in saline) was administrated to mice 1 h before ischemia. Liver and blood samples were collected 6 h after reperfusion. Hepatic IR increased hepatocellular oxidative damage and induced mitochondrial dysfunction. These phenomena were ameliorated by genipin. Hepatic IR also increased the level of mitochondrial fission, such as dynamin-related protein 1 and the level of PINK1 protein expression. In contrast, hepatic IR decreased the levels of mitochondrial biogenesis related proteins (e.g., peroxisome proliferator-activated receptor gamma coactivator 1α, nuclear respiratory factor 1, and mitochondrial transcription factor A), mitophagy related proteins (e.g., Parkin), and fusion related protein (e.g., mitofusin 2). Furthermore, hepatic IR decreased the levels of sirtuin1 protein and phosphorylation of AMP-activated protein kinase. Genipin alleviated these IR-induced changes. These data indicate that genipin protects against IR-induced hepatic injury via regulating mitochondrial QC. (225/250).