Ethanol Extract of Pinus koraiensis Leaf Ameliorates Alcoholic Fatty Liver via the Activation of LKB1–AMPK Signaling In Vitro and In Vivo

Although Pinus koraiensis leaf (PKL) was reported for its anti‐diabetes, anti‐obesity and anticancer effects as a folk remedy, the inhibitory effect of PKL on alcoholic fatty liver has never been elucidated yet. This study investigated the molecular mechanisms of PKL on alcoholic fatty liver in HepG2 cells, Sprague Dawley (SD) rats and Imprinting Control Region (ICR) mice. Pinus koraiensis leaf increased phosphorylation of liver kinase B1 (LKB1)/AMP‐activated protein kinase signaling, low‐density lipoprotein receptor and decreased fatty acid biosynthesis‐related proteins such as sterol regulatory element‐binding protein 1c, fatty acid synthase, 3‐hydroxy‐3‐methylglutaryl‐CoA reductase in HepG2 cells. In SD rats with 25% alcohol‐induced fatty liver, PKL suppressed the levels of aspartate aminotransferase and triglyceride and also enhanced the activities of antioxidant enzymes including superoxide dismutase, glutathione peroxidase and glutathione s‐transferase compared with untreated control. Furthermore, PKL increased serum alcohol dehydrogenase and serum aldehyde dehydrogenase, but decreased serum alcohol concentration in ICR mice after alcohol administration. Consistently, histochemical analysis revealed that PKL attenuated alcohol‐induced fatty liver in SD rats. Overall, these findings suggest that PKL ameliorates alcohol‐induced fatty liver via activation of LKB1–AMP‐activated protein kinase and modulation of proteins related to lipogenesis synthesis, cholesterol synthesis and fatty acid oxidation. Copyright © 2017 John Wiley & Sons, Ltd.