Susceptibility to hypoxia/reoxygenation of aged rat cardiomyocytes and its modulation by selenium supplementation.
Since in the aged heart an increased basal production of reactive oxygen species (ROS) has been demonstrated, and the resistance to ROS attack could be ameliorated by antioxidant supplementation, we verified the protective effect of selenium, as sodium selenite (SS) or seleno methionine (SM), in cultured rat cardiomyocytes aged in vitro. In normoxia, glutathione peroxidase (GPx) activity and total antioxidant activity were higher in old than in young cardiomyocytes, suggesting the existence of a compensatory increase of antioxidant defenses. When aged cells were submitted to hypoxia/reoxygenation, GPx activity was not modified; while total antioxidant activity decreased, conjugated diene level increased. Selenium supplementation, particularly as SM, was able to increase GPx, and consequently total antioxidant activity, and to decrease conjugated diene production. The observed ability of selenium supplementation to protect aged cardiomyocytes from hypoxia/reoxygenation damage underlines the importance of an optimal selenium dietary intake, particularly in the elderly.
Bordoni
Alessandra
A
Nutrition Research Center, Department of Biochemistry G. Moruzzi, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy. alessandra.bordoni@unibo.it
Biagi
Pier Luigi
PL
Angeloni
Cristina
C
Leoncini
Emanuela
E
Danesi
Francesca
F
Hrelia
Silvana
S
D000375:Aging; D000818:Animals; D000975:Antioxidants / Q000032:analysis; D015687:Cell Hypoxia / Q000187:drug effects*; D002478:Cells, Cultured; D005979:Glutathione Peroxidase / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000187:drug effects / Q000378:metabolism*; D010100:Oxygen / Q000008:administration & dosage*; D051381:Rats; D017208:Rats, Wistar; D012643:Selenium / Q000008:administration & dosage*; D012645:Selenomethionine / Q000008:administration & dosage; D018038:Sodium Selenite / Q000008:administration & dosage
D000975:Antioxidants; D012645:Selenomethionine; D005979:Glutathione Peroxidase; D012643:Selenium; D018038:Sodium Selenite; D010100:Oxygen