title: Genistein, EGCG, and capsaicin inhibit adipocyte differentiation process via activating AMP-activated protein kinase.
abstract: Phytochemicals such as soy isoflavone genistein have been reported to possess therapeutic effects for obesity, diabetes, and cardiovascular diseases. In the present study, the molecular basis of selective phytochemicals with emphasis on their ability to control intracellular signaling cascades of AMP-activated kinase (AMPK) responsible for the inhibition of adipogenesis was investigated. Recently, the evolutionarily conserved serine/threonine kinase, AMPK, emerges as a possible target molecule of anti-obesity. Hypothalamic AMPK was found to integrate nutritional and hormonal signals modulating feeding behavior and energy expenditure. We have investigated the effects of genistein, EGCG, and capsaicin on adipocyte differentiation in relation to AMPK activation in 3T3-L1 cells. Genistein (20-200muM) significantly inhibited the process of adipocyte differentiation and led to apoptosis of mature adipocytes. Genistein, EGCG, and capsaicin stimulated the intracellular ROS release, which activated AMPK rapidly. We suggest that AMPK is a novel and critical component of both inhibition of adipocyte differentiation and apoptosis of mature adipocytes by genistein or EGCG or capsaicin further implying AMPK as a prime target of obesity control.
authors.affiliation: Department of Biochemistry and Molecular Biology, Medical Research Center for Bioreaction to Reactive Oxygen Species, Kyung Hee University College of Medicine, Seoul 130-701, Republic of Korea.
authors.forename: Jin-Taek
authors.initials: JT
authors.lastname: Hwang
authors.forename: In-Ja
authors.initials: IJ
authors.lastname: Park
authors.forename: Jang-In
authors.initials: JI
authors.lastname: Shin
authors.forename: Yun Kyoung
authors.initials: YK
authors.lastname: Lee
authors.forename: Seong Kyu
authors.initials: SK
authors.lastname: Lee
authors.forename: Haing Woon
authors.initials: HW
authors.lastname: Baik
authors.forename: Joohun
authors.initials: J
authors.lastname: Ha
authors.forename: Ock Jin
authors.initials: OJ
authors.lastname: Park
mesh_terms: D041721:3T3-L1 Cells; D055372:AMP-Activated Protein Kinases; D017667:Adipocytes / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D002211:Capsaicin / Q000008:administration & dosage*; D002392:Catechin / Q000008:administration & dosage / Q000031:analogs & derivatives*; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D004789:Enzyme Activation / Q000187:drug effects; D019833:Genistein / Q000008:administration & dosage*; D051379:Mice; D009097:Multienzyme Complexes / Q000187:drug effects / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000187:drug effects / Q000378:metabolism*
chemical_list: D004338:Drug Combinations; D009097:Multienzyme Complexes; D002392:Catechin; C045651:epigallocatechin gallate; D019833:Genistein; D017346:Protein Serine-Threonine Kinases; D055372:AMP-Activated Protein Kinases; D002211:Capsaicin