Tumeric Ethanol Extract Up-regulated the Lipolysis by Activation of Lipase Related Pathway in HepG2 Cells

Abstract

In current, we investigated the effect of tumeric ethanol extract (TEE) on underlying mechanisms of lipolysis in HepG2 hepatocytes. The intracellular lipid droplets were stained and quantified. In comparison with the control, lipid accumulation with 72-hours treatment of TEE was significantly decreased by 25.8% at concentration of 100 µg/mL. In consistence with a result, the cellular triglyceride (TG) content was reduced by 22.3% at concentration of 100 µg/mL, respectively. To determine the action mode of reduction in TG content, the glycerol release and level of glucose uptake were measured. At first, incubation of HepG2 hepatocytes with 50 and 100 g/mL of TEE for 4 hours significantly decreased the extracellular uptake of glucose by 7.4% and 10.4%. The free glycerol level released into the cultured media were significantly increased with 50 and 100 µg/mL of TEE treatment by 20.8% and 29.1%, but there was no time-dependent effect. As subsequently measured by quantitative real-time polymerase chain reaction, mRNA level of hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL), but not lipoprotein lipase (LPL), was significantly increased by 25.2% and 31.1% at concentration of 100 µg/mL. The present study suggested that TEE partially inhibited lipogenesis by suppressing glucose uptake and enhanced lipolysis through upregulation of HSL and ATGL mRNA expression, resulting in increased glycerol release.