Effects of Severe or Marginal Folate Deficiency on Antioxidant Capacity and Induced Lipid Peroxidation in Rats

• Main Authors: Hsu, Yu-Chin, 許玉卿
• Other Authors: 許瑞芬
• Format: Others
• Language: zh-TW
• Published: 1998
• Online Access: http://ndltd.ncl.edu.tw/handle/42105422442728306637

碩士 === 輔仁大學 === 食品營養學系 === 86 === The purpose of this study was to investigate the effect of severe or marginal folate deficiency on folate status, antioxidant capacity and induced lipid peroxidation in male weanling F344 and Wistar rats. The diets used in this studies were an amino-acid defined basal diet containing 1% (w/w) succinylsulphathiazol, and representative of various levels of folic acid as control group (+8 mg/kg diet), moderate folate group (+2 mg/kg diet), low folate group (+0.5 mg/kg diet) and folate deficient group (+0 mg/kg diet). In experiment Ⅰ, F344 rats received moderate or low folate diet for 8 weeks, folate concentration in serum, plasma and organs significantly decreased, without theoccurrence of anemia. Glutathione peroxidase (GPX) activity in hepatic extracts of moderate folate group were descreased. Liver microsome fraction of moderate folate group had an increase of thiobarbituric acid reactive substance (TBARS) values as challenged with Fe2+. In experiment Ⅱ, male weanling Wistar rats fed moderate, low folate or folate deficient diet 4 weeks exhibit no sign of anemia, but folate concentration in blood and organ decreased in parallel with the decrease of dietary folate levels. Hepatocytes GSH/GSSG ratio of low folate and moderate folate group were increasing, GPX activity of folate deficient group were decreased, glutathione reductase (GR) activity of low folate and moderate folate group were increasing, superoxide dismutase (SOD) activity of low folate and folate deficient group were decreased. TBARS values in liver homogenate extracted from low folate, moderate folate and folate deficient group were significantly increased. Folate-deficient animals have an increase of TBARS values measured from nuclear, mitochondria or microsome fraction extracted from livers, either induced by addition of H2O2 or Fe2+. In experiment Ⅱ, Wistar rats received folate deficient diets 2, 4, 6 weeks, folate levels of blood and organs have acutely decreased when folate deficient 2 weeks. By 6 weeks folate deficiency has shown the sign of hepatomegaly and fatty liver. Hepatocytes GSH, GSSG level and GPX, SOD and catalase (CAT) activity of folate deficient group were decreased, GR activity were increasing. TBARS values in liver homogenate extracted, nuclear, mitochondria and microsome were significantly increasing, when challenged with H2O2 or Fe2+. In summary, rats fed moderate, low folate diet, 4 weeks or 8 weeks, folate status were decreased but without the occurrence of anemia, similar as human marginal folate deficiency. Rats fed folate deficient diet, folate status were rapidly decreased, animals exhibit anemia similar as human severe folate deficiency. Either severe or marginal folate deficiency affected antioxidant enzymes activity and induced lipid peroxidation may induction of oxidative damage.