The role of reactive oxygen species in diabetes-induced anomalies in embryos of Cohen diabetic rats.
The role of the antioxidant defense mechanism in diabetes-induced anomalies was studied in the Cohen diabetes-sensitive (CDs) and -resistant (CDr) rats, a genetic model of nutritionally induced type 2 diabetes mellitus. Embryos, 12.5-day-old, of CDs and CDr rats fed regular diet (RD) or a diabetogenic high-sucrose diet (HSD) were monitored for growth retardation and congenital anomalies. Activity of superoxide dismutase (SOD) and catalase-like enzymes and levels of ascorbic acid (AA), uric acid (UA), and dehydroascorbic acid (DHAA) were measured in embryonic homogenates. When fed RD, CDs rats had a decreased rate of pregnancy, and an increased embryonic resorption. CDs embryos were smaller than CDr embryos; 46% were maldeveloped and 7% exhibited neural tube defects (NTDs). When fed HSD, rate of pregnancy was reduced, resorption rate was greatly increased (56%; P < .001), 47.6% of the embryos were retrieved without heart beats, and 27% exhibited NTD. In contrast, all the CDr embryos were normal when fed RD or HSD. Activity of SOD and catalase was not different in embryos of CDs and CDr rats fed RD. When fed HSD, levels of AA were significantly reduced, the ratio DHAA/AA was significantly increased, and SOD activity was not sufficiently increased when compared to embryos of CDr. The reduced fertility of the CDs rats, the growth retardation, and NTD seem to be genetically determined. Maternal hyperglycemia seems to result in environmentally induced embryonic oxidative stress, resulting in further embryonic damage.
Zangen
Sarah W
SW
Laboratory of Teratology, Department of Anatomy and Cell Biology, Hebrew University-Hadassah Medical School, Jerusalem, Israel.
Yaffe
Pirhiya
P
Shechtman
Svetlana
S
Zangen
David H
DH
Ornoy
Asher
A
D000818:Animals; D000831:Animals, Newborn; D001205:Ascorbic Acid / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D000013:Congenital Abnormalities / Q000209:etiology*; D003683:Dehydroascorbic Acid / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000503:physiopathology*; D004622:Embryo, Mammalian / Q000502:physiology*; D005314:Embryonic and Fetal Development / Q000187:drug effects / Q000502:physiology; D005260:Female; D005298:Fertility / Q000502:physiology; D005865:Gestational Age; D011247:Pregnancy; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012016:Reference Values; D013395:Sucrose / Q000494:pharmacology; D013482:Superoxide Dismutase / Q000378:metabolism; D014527:Uric Acid / Q000378:metabolism
D017382:Reactive Oxygen Species; D014527:Uric Acid; D013395:Sucrose; D002374:Catalase; D013482:Superoxide Dismutase; D001205:Ascorbic Acid; D003683:Dehydroascorbic Acid