title: Esculetin induces mitochondria-mediated apoptosis in 3T3-L1 adipocytes.
abstract: Adipose tissue mass is determined by the volume and the number of adipocytes and is subjected to homeostatic regulation involving cell death mechanisms. We investigated the effects of esculetin, a coumarin compound, on apoptotic signaling in 3T3-L1 adipocytes. Esculetin treatment induced an increase in expression of Bax with a concomitant decrease of Bcl-2 in a time-dependent manner. Esculetin treatment also resulted in translocation of cytochrome c from mitochondria to cytosol and cleavage of 116 kDa poly(ADP-ribose) polymerase (PARP)-1, resulting in the accumulation of an 85 kDa cleavage product in a caspase-dependent manner. Furthermore, esculetin selectively altered the phosphorylation state of members of the MAPK superfamily, causing dephosphorylation of extracellular signal-regulating kinase 1/2 (ERK1/2) and hyperphosphorylation of c-Jun-N-terminal kinase (JNK). In addition, an inhibitor of the JNK MAP kinase pathway, SP600125, reduced esculetin-induced cytochrome c release. These results indicate that esculetin mediated adipocyte apoptosis involves the mitochondrial pathway. Esculetin thus decreases adipocyte number by initiating this apoptotic process in 3T3-L1 adipocytes.
authors.affiliation: Department of Animal and Dairy Science, University of Georgia, Athens, GA 30602-2771, USA.
authors.forename: Jeong-Yeh
authors.initials: JY
authors.lastname: Yang
authors.forename: Mary Anne
authors.initials: MA
authors.lastname: Della-Fera
authors.forename: Clifton A
authors.initials: CA
authors.lastname: Baile
mesh_terms: D041721:3T3-L1 Cells; D000818:Animals; D000873:Anthracenes / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D045304:Cytochromes c / Q000378:metabolism; D048031:JNK Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis; D014468:Umbelliferones / Q000494:pharmacology*
chemical_list: D000873:Anthracenes; D019253:Proto-Oncogene Proteins c-bcl-2; D014468:Umbelliferones; C432165:pyrazolanthrone; D045304:Cytochromes c; C499321:Parp1 protein, mouse; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D053148:Caspase 3; C007628:esculetin