0000000000261175
AUTHOR
Esperanza Gasco
Exhaustive physical exercise causes oxidation of glutathione status in blood: Prevention by antioxidant administration
We have studied the effect of exhaustive concentric physical exercise on glutathione redox status and the possible relationship between blood glutathione oxidation and blood lactate and pyruvate levels. Levels of oxidized glutathione (GSSG) in blood increase after exhaustive concentric physical exercise in trained humans. GSSG levels were 72% higher immediately after exercise than at rest. They returned to normal values 1 h after exercise. Blood reduced glutathione (GSH) levels did not change significantly after the exercise. We have found a linear relationship between GSSG-to-GSH and lactate-to-pyruvate ratios in human blood before, during, and after exhaustive exercise. In rats, physical…
Anti-rat liver microsomal and cytosolic antibodies in hepatitis C virus infection.
In order to assess the frequency of autoimmunity markers in hepatitis C virus infection, 229 RIBA 2 HCV positive individuals were tested by ELISA and Immunoblot assay using as antigen rat liver microsomal and cytosolic proteins. Twenty-one out of 229 individuals (9%) showed anti-rat liver microsome antibodies by ELISA, but the titre was low (1:100 to 1:1,600). In Immunoblot, only 5 of these 21 ELISA positive sera recognized also rat liver microsomal proteins (MW between 30 to 64 kDa). Antibodies against rat liver cytosolic proteins were found by ELISA in 14 out of 229 individuals (6%). Three of them showed a reactivity in Immunoblot to 42 kDa or 55 kDA proteins. In conclusion, HCV infection…
Effect of a Diet Supplemented with alpha-Tocopherol and beta-Carotene on ATP and Antioxidant Levels after Hepatic Ischemia-Reperfusion.
Ischemia-reperfusion injury associated with liver transplantation remains a serious complication in clinical practice. In the present study the effect of intake of alpha-tocopherol or beta-carotene to limit liver injury by oxidative stress in ischemia and reperfusion was explored. Wistar rats were fed with diets enriched with alpha-tocopherol (20 mg/day) or beta-carotene (3 mg/day) for 21 days. After 21 days, their livers were subjected to 15 and 30 min of ischemia and afterwards were reperfused for 60 min. The recovery of levels of ATP during reperfusion was better in the group of rats whose diets were supplemented with alpha-tocopherol or beta-carotene than in the group control. The suppl…
L-cysteine and glutathione metabolism are impaired in premature infants due to cystathionase deficiency.
There are conflicting reports in the literature as to whether L-cysteine is an essential amino acid in premature infants as the result of the absence of hepatic cystathionase activity. To analyze the physiological importance of the cystathionase deficiency, we studied sulfur amino acid metabolism in human neonates of different gestational ages. Plasma cystathionine concentrations are higher in premature infants < or = 32 wk gestation (group 1) than in premature infants of 33-36 wk gestational age (group 2) or in full-term infants (group 3), whereas plasma cysteine concentrations are much lower in group 1 and 2 premature infants than in mature infants. Furthermore, erythrocytes from group 1 …
Effect of aging on metabolic zonation in rat liver: acinar distribution of GSH metabolism.
The effect of age on the glutathione antioxidant system and its acinar distribution in rat liver was studied. GSH/GSSG ratio in blood and liver was lower in old than in young rats. Hepatic glutathione peroxidase and glutathione S-transferase activities were higher in old than in young rats, whereas hepatic gamma-glutamyl transpeptidase activity was lower in old than in young rats. Glutathione reductase and glucose-6-phosphate dehydrogenase activities did not change with age in rat liver. Total glutathione levels and glutathione peroxidase activity were higher in periportal than in perivenous areas of young rats, but this heterogeneous distribution did not occur in old rats. No change with a…