title: Vaspin prevents methylglyoxal-induced apoptosis in human vascular endothelial cells by inhibiting reactive oxygen species generation.
abstract: OBJECTIVE
  Vaspin (visceral adipose tissue-derived serine protease inhibitor) is a novel adipocytokine found in visceral white adipose tissues of obese type 2 diabetic rats. We have previously shown that vaspin has anti-inflammatory and antimigratory effects in vascular smooth muscle cells. Methylglyoxal (MGO) is an active metabolite of glucose and mediates diabetic vascular complications including endothelial cell (EC) apoptosis. Nonetheless, effects of vaspin on MGO-induced apoptosis of vascular EC remain to be determined. We investigated the effects of vaspin on MGO-induced apoptosis of human umbilical vein ECs (HUVECs).
  
  
  METHODS
  Human umbilical vein ECs were treated with MGO (560 μm, 12 h) in the absence or presence of vaspin (1 ng mL(-1), pre-treatment for 2 h). Cell death was evaluated by a cell counting assay. Apoptosis was determined by a terminal deoxyribonucleotide transferase-mediated deoxyuridine triphosphate nick-end labelling (TUNEL) assay. Cleaved caspase-3 expression was determined by Western blotting. Reactive oxygen species (ROS) generation was fluorometrically measured using 2', 7'-dichlorodihydrofluorescein diacetate. NADPH oxidase (NOX) activity was determined by a lucigenin assay.
  
  
  RESULTS
  Vaspin significantly inhibited MGO-induced HUVEC death. Vaspin significantly attenuated MGO-increased TUNEL-positive ECs. Moreover, vaspin significantly inhibited MGO-induced caspase-3 cleavage. Vaspin significantly inhibited MGO-induced ROS generation as well as NOX activation.
  
  
  CONCLUSIONS
  The present results for the first time demonstrate that vaspin inhibits MGO-induced EC apoptosis by preventing caspase-3 activation via the inhibition of NOX-derived ROS generation.
authors.affiliation: Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Aomori, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Phalitakul
authors.forename: M
authors.initials: M
authors.lastname: Okada
authors.forename: Y
authors.initials: Y
authors.lastname: Hara
authors.forename: H
authors.initials: H
authors.lastname: Yamawaki
mesh_terms: D000166:Acridines / Q000378:metabolism; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D053148:Caspase 3 / Q000378:metabolism; D002452:Cell Count; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects* / Q000378:metabolism*; D006801:Humans; D020287:In Situ Nick-End Labeling; D032389:Myocytes, Smooth Muscle / Q000187:drug effects; D011765:Pyruvaldehyde / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015843:Serpins / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D000166:Acridines; D017382:Reactive Oxygen Species; C507339:SERPINA12 protein, human; D015843:Serpins; C033472:10,10'-dimethyl-9,9'-biacridinium; D011765:Pyruvaldehyde; D053148:Caspase 3
keywords: adipocytokine; apoptosis; methylglyoxal; reactive oxygen species; vascular endothelial cell