title: Activation of AMP-activated protein kinase reduces hyperglycemia-induced mitochondrial reactive oxygen species production and promotes mitochondrial biogenesis in human umbilical vein endothelial cells.
abstract: We previously proposed that the production of hyperglycemia-induced mitochondrial reactive oxygen species (mtROS) is a key event in the development of diabetes complications. The association between the pathogenesis of diabetes and its complications and mitochondrial biogenesis has been recently reported. Because metformin has been reported to exert a possible additional benefit in preventing diabetes complications, we investigated the effect of metformin and 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR) on mtROS production and mitochondrial biogenesis in cultured human umbilical vein endothelial cells. Treatment with metformin and AICAR inhibited hyperglycemia-induced intracellular and mtROS production, stimulated AMP-activated protein kinase (AMPK) activity, and increased the expression of peroxisome proliferator-activated response-gamma coactivator-1alpha (PGC-1alpha) and manganese superoxide dismutase (MnSOD) mRNAs. The dominant negative form of AMPKalpha1 diminished the effects of metformin and AICAR on these events, and an overexpression of PGC-1alpha completely blocked the hyperglycemia-induced mtROS production. In addition, metformin and AICAR increased the mRNA expression of nuclear respiratory factor-1 and mitochondrial DNA transcription factor A (mtTFA) and stimulated the mitochondrial proliferation. Dominant negative-AMPK also reduced the effects of metformin and AICAR on these observations. These results suggest that metformin normalizes hyperglycemia-induced mtROS production by induction of MnSOD and promotion of mitochondrial biogenesis through the activation of AMPK-PGC-1alpha pathway.
authors.affiliation: Department of Metabolic Medicine, Faculty of Medical and Pharmaceutical Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kukidome
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nishikawa
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Sonoda
authors.forename: Koujiro
authors.initials: K
authors.lastname: Imoto
authors.forename: Kazuo
authors.initials: K
authors.lastname: Fujisawa
authors.forename: Miyuki
authors.initials: M
authors.lastname: Yano
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Motoshima
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Taguchi
authors.forename: Takeshi
authors.initials: T
authors.lastname: Matsumura
authors.forename: Eiichi
authors.initials: E
authors.lastname: Araki
mesh_terms: D055372:AMP-Activated Protein Kinases; D000620:Aminoimidazole Carboxamide / Q000031:analogs & derivatives / Q000378:metabolism; D002478:Cells, Cultured; D004272:DNA, Mitochondrial / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D042783:Endothelial Cells / Q000166:cytology* / Q000201:enzymology*; D004789:Enzyme Activation / Q000187:drug effects; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D006943:Hyperglycemia / Q000378:metabolism* / Q000473:pathology; D007004:Hypoglycemic Agents / Q000494:pharmacology; D008687:Metformin / Q000494:pharmacology; D008928:Mitochondria / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000378:metabolism; D009097:Multienzyme Complexes / Q000235:genetics / Q000378:metabolism*; D051265:NF-E2-Related Factor 1 / Q000378:metabolism; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012265:Ribonucleotides / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D004272:DNA, Mitochondrial; D004268:DNA-Binding Proteins; D006360:Heat-Shock Proteins; D007004:Hypoglycemic Agents; D024101:Mitochondrial Proteins; D009097:Multienzyme Complexes; D051265:NF-E2-Related Factor 1; C486497:PPARGC1A protein, human; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D012265:Ribonucleotides; D014157:Transcription Factors; C422562:mitochondrial transcription factor A; D000620:Aminoimidazole Carboxamide; D008687:Metformin; D013482:Superoxide Dismutase; D017346:Protein Serine-Threonine Kinases; D055372:AMP-Activated Protein Kinases; C031143:AICA ribonucleotide