title: Cardioprotective effects of dihydrolipoic acid and tocopherol in right heart hypertrophy during oxidative stress.
abstract: Rat hearts hypertrophied by exposure of the animals to low oxygen pressure were perfused by the Langendorff technique. After oxidative stress induced by hypoxia/reoxygenation, functional recovery of the hypertrophied right heart was insufficient when compared to non-hypertrophied controls. Accordingly, mitochondrial membrane potential did not recover sufficiently. There was a positive trend for improvement of the rate-pressure product during reoxygenation in lipoic acid (CAS 1077-28-7; 0.8 mumol/l) treated hearts which was also verified for membrane potential. Adenosine 5'-triphosphate and creatine phosphate contents as well as the ATP/ADP ratio in hypertrophied right ventricle were significantly increased after reoxygenation in hearts treated with lipoic acid. With lipoic acid, there was a significantly higher content of glutathione (oxidized form) after reoxygenation, Ca2+ uptake was significantly increased in mitochondria isolated from hypertrophied right ventricles and treated by 12 nmol/mg protein of lipoic acid. The results reveal a distinct improvement of mitochondrial structure/function by lipoic acid and suggest for therapy a combination with the synergistic free radical scavenging properties of tocopherol (CAS 10191-41-0).
authors.affiliation: Gustav-Embden-Zentrum der Biologischen Chemie, Arbeitsgruppe Membranstruktur.
authors.forename: T
authors.initials: T
authors.lastname: Thürich
authors.forename: J
authors.initials: J
authors.lastname: Bereiter-Hahn
authors.forename: M
authors.initials: M
authors.lastname: Schneider
authors.forename: G
authors.initials: G
authors.lastname: Zimmer
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000627:therapeutic use*; D002118:Calcium / Q000378:metabolism; D006332:Cardiomegaly / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D003326:Coronary Circulation / Q000502:physiology; D003402:Creatine Kinase / Q000378:metabolism; D016166:Free Radical Scavengers / Q000627:therapeutic use*; D005978:Glutathione / Q000378:metabolism; D006334:Heart Function Tests; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D008929:Mitochondria, Heart / Q000378:metabolism; D008933:Mitochondrial Swelling / Q000187:drug effects; D018384:Oxidative Stress / Q000502:physiology*; D010477:Perfusion; D051381:Rats; D017208:Rats, Wistar; D008063:Thioctic Acid / Q000031:analogs & derivatives* / Q000627:therapeutic use; D014810:Vitamin E / Q000627:therapeutic use*
chemical_list: D000975:Antioxidants; D016166:Free Radical Scavengers; D014810:Vitamin E; D008063:Thioctic Acid; C015144:dihydrolipoic acid; D000255:Adenosine Triphosphate; D003402:Creatine Kinase; D005978:Glutathione; D002118:Calcium