retinol-palmitate and Hemolysis

To investigate the significance of the lowered plasma vitamin A during the last few weeks of pregnancy, the capacity of erythrocyte lysates to destroy vitamin A in vitro and the alteration in ammonium nitrogen to creatinine ratio (Am N/Cr) in random urine samples was followed up at different gestational ages in women from low income groups. One group received no supplementation and the other received supplements of 1800 retinol equivalents (RE) and at most points the number of observations were not less than 12. In the unsupplemented women there was a significant increase in the capacity of erythrocytes to destroy vitamin A in vitro, which reflects an increased oxidative stress as compared to the supplemented group. While differences in mean Am N/Cr did not follow any consistent pattern, there was a strong association between lowered plasma vitamin A (< 35 micrograms/dl) and increased Am N/Cr ratio (> 0.5). This was true only when combined data of both groups were considered till 26 weeks of gestation and not beyond. As expected in supplemented women there was no significant fall in the plasma vitamin A during term. These data reveal that the lowered plasma vitamin A levels are suggestive of greater risk of hypovitaminosis A during pregnancy as indicated by the oxidative stress in erythrocytes.

Topics: Chi-Square Distribution; Colorimetry; Creatinine; Diterpenes; Erythrocytes; Female; Ferrous Compounds; Follow-Up Studies; Hemolysis; Humans; Pregnancy; Quaternary Ammonium Compounds; Retinyl Esters; Sensitivity and Specificity; Time Factors; Vitamin A

Rats were maintained on a vitamin E free diet containing 20% safflower oil for a period of 12 weeks at two dietary protein levels, 20% and 10% casein. Enhanced in vitro tissue lipid peroxidation and lysis of erythrocytes were noticed at both the protein levels. A reduction in body mass and tissue weights were observed in both the protein groups but more so at 20% protein level. Feeding of retinyl palmitate (100 000 IU/100 g body weight) for 4 consecutive days to -E rats inhibited liver and kidney in vitro lipid peroxidation. Ascorbic acid (150 mg/100 g body weight) given orally for 5 days to -E rats inhibited liver brain and kidney in vitro peroxidation. Lysis of erythrocytes from -E rats was further increased by dosing with both the vitamins "A" and "C", the latter being more effective. The stromal enzymes acetyl choline esterase and ATPase were lowered, following the hemolysis profile of the erythrocytes from the different groups. Glutathione content of erythrocytes were unaffected except in -E +C group. In all groups the higher protein level (20%) produced greater lysis as compared to 10% level. It is concluded that 20% protein is more injurious in vitamin E deficiency simultaneously made hypervitaminosis A or C.

Topics: Animals; Ascorbic Acid; Dietary Fats; Dietary Proteins; Diterpenes; Hemolysis; Lipid Peroxides; Male; Oxidation-Reduction; Rats; Retinyl Esters; Vitamin A; Vitamin E Deficiency