Methanolic Extract of Turmeric (Curcuma longa L.) Enhanced the Lipolysis by Up-regulation of Lipase mRNA Expression in Differentiated 3T3-L1 Adipocytes

Effects of methanol extract from turmeric (Curcuma longa L.) (CME) on underlying mechanisms of lipolysis were investigated in 3T3-L1 adipocytes. Compared to the control, lipid accumulation with 72 hr treatment of CME at the concentration 20 ㎍/㎖ was significantly decreased by 19.9% as quantified by Oil red O dye. Intracellular triglyceride (TG) content was also lowered by 19.3%. To determine the mechanism for TG content reduction, glycerol release level was measured. Incubation of 3T3-L1 adipocytes with 15 and 20 ㎍/㎖ of CME significantly elevated the level of free glycerol released into the cultured medium by 20.4 and 28.6%, respectively. In subsequent measurements using quantitative real-time polymerase chain reaction (PCR), mRNA levels of hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL) were significantly increased by 21.2 and 24.9%, respectively, at the concentration 20 ㎍/㎖. Results indicated that CME stimulated lipolysis through induction of HSL and ATGL mRNA expressions, resulting in increased glycerol release.