Papaya Leaf Extract Ameliorates Hepatic Steatosis in High-Fat Diet–Induced Obese Mice and Oleic Acid–Stimulated HepG2 Cells

Abstract

Hepatic steatosis, characterized by the accumulation of lipids in hepatocytes, is a chronic stage of nonalcoholic fatty liver disease (NAFLD). Papaya (Carica papaya L.), belonging to the Caricaceae family, possesses therapeutic and nutritional properties. Notably, papaya leaves have medicinal properties; however, their effect on hepatic steatosis remains to be elucidated. Therefore, in this study, we investigated the ameliorative effect of papaya leaf extract (PLE) on hepatic steatosis using a high-fat diet (HFD)–induced obese mice and oleic acid (OA)–treated HepG2 cells. Administration of PLE ameliorated body weight gain and hepatic lipid accumulation in HFD-induced obese mice. Furthermore, PLE decreased the expression of critical adipogenic markers, including CCAAT/enhancer-binding protein α (C/EBPα), sterol regulatory element-binding protein 1 (SREBP-1), and peroxisome proliferator-activated γ (PPARγ), in the liver. The expression of phospho-adenosine monophosphate-activated protein kinase (p-AMPK) increased in the liver of PLE-administered mice. Consistent with the in vivo study, PLE reduced lipid accumulation and the protein expression of adipogenic factors and increased p-AMPK expression in OA-treated HepG2 cells. Collectively, these results indicate the potential of PLE as a therapeutic agent for obesity-induced hepatic steatosis.