Naringenin Ameliorates Palmitic Acid-induced Fatty Acid Stress in Hepatocytes

Type 2 diabetes is strongly associated with the development of insulin resistance in metabolically active tissues. Non-alcoholic fatty liver disease (NAFLD) is considered to be a manifestation of hepatic insulin resistance. Saturated fatty acids such as palmitic acid (PA) induce insulin resistance, which may be studied for therapeutic prevention by herbal agents. In the present study, the role of naringenin, a bioflavonoid, is examined in PA-induced cytotoxicity in human hepatocellular carcinoma (HepG2) cells. PA causes significant inflammation and apoptosis in these cells primarily by inhibiting phosphorylation of Akt at serine 473 residue. Apoptosis assay, mitochondrial transmembrane potential measurement and immunoblotting for protein expressions have been used for demonstrating PA-induced abnormalities. Naringenin treatment effectively inhibits the fatty acid-induced inflammation and cytotoxicity, along with improvement of insulin signalling. Naringenin has a potential to prevent the fatty acid-induced stresses in hepatocytes, and may be beneficial for improving hepatic insulin sensitivity and mitigating lipotoxicity.