title: Caffeine attenuates lipid accumulation via activation of AMP-activated protein kinase signaling pathway in HepG2 cells.
abstract: The main purpose of this study is to examine the effect of caffeine on lipid accumulation in human hepatoma HepG2 cells. Significant decreases in the accumulation of hepatic lipids, such as triglyceride (TG), and cholesterol were observed when HepG2 cells were treated with caffeine as indicated. Caffeine decreased the mRNA level of lipogenesis-associated genes (SREBP1c, SREBP2, FAS, SCD1, HMGR and LDLR). In contrast, mRNA level of CD36, which is responsible for lipid uptake and catabolism, was increased. Next, the effect of caffeine on AMP-activated protein kinase (AMPK) signaling pathway was examined. Phosphorylation of AMPK and acetyl-CoA carboxylase were evidently increased when the cells were treated with caffeine as indicated for 24 h. These effects were all reversed in the presence of compound C, an AMPK inhibitor. In summary, these data indicate that caffeine effectively depleted TG and cholesterol levels by inhibition of lipogenesis and stimulation of lipolysis through modulating AMPK-SREBP signaling pathways.
authors.affiliation: Department of Pharmacology and Clinical Pharmacy, College of Pharmacy, Kyung Hee University, Seoul 130-701, Korea.
authors.forename: Hai Yan
authors.initials: HY
authors.lastname: Quan
authors.forename: Do Yeon
authors.initials: DY
authors.lastname: Kim
authors.forename: Sung Hyun
authors.initials: SH
authors.lastname: Chung
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D000103:Acetyl-CoA Carboxylase / Q000378:metabolism; D018955:CD36 Antigens / Q000235:genetics / Q000378:metabolism; D002110:Caffeine / Q000494:pharmacology*; D002784:Cholesterol / Q000378:metabolism; D056945:Hep G2 Cells; D006801:Humans; D050155:Lipogenesis / Q000187:drug effects / Q000235:genetics; D008066:Lipolysis / Q000187:drug effects; D010766:Phosphorylation; D011720:Pyrazoles / Q000494:pharmacology; D011743:Pyrimidines / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D011973:Receptors, LDL / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects*; D013230:Stearoyl-CoA Desaturase / Q000235:genetics / Q000378:metabolism; D051780:Sterol Regulatory Element Binding Protein 1 / Q000235:genetics / Q000378:metabolism; D014280:Triglycerides / Q000378:metabolism*; D019014:fas Receptor / Q000235:genetics / Q000378:metabolism
chemical_list: D018955:CD36 Antigens; D011720:Pyrazoles; D011743:Pyrimidines; D012333:RNA, Messenger; D011973:Receptors, LDL; D051780:Sterol Regulatory Element Binding Protein 1; D014280:Triglycerides; D019014:fas Receptor; C516138:dorsomorphin; D002110:Caffeine; D002784:Cholesterol; D013230:Stearoyl-CoA Desaturase; D055372:AMP-Activated Protein Kinases; D000103:Acetyl-CoA Carboxylase