IDDF2019-ABS-0229 Biochemical and molecular effects of 17β estradiol on membrane functions in aged rat liver

Abstract

Background Free radical production and oxidative stress are known to increase in the liver during aging and may contribute to the oxidative damage. Aging in females and males is considered as the end of natural protection against age-related diseases like osteoporosis, coronary heart disease, diabetes, Alzheimer’s disease, and Parkinson’s disease. These changes increase during the menopausal condition in females when the level of estradiol is decreased. The objective of this study was to observe the changes in activities of membrane-linked ATPases (Na +/K + ATPase, Ca2+ ATPase), antioxidant enzymes (superoxide dismutase, glutathione-S-transferase), lipid peroxidation levels, lipofuscin content, glucose transporters 2 (GLUT 2) expression and membrane fluidity occurring in livers of female rats of 3, 12 and 24 months age groups, and to see whether these changes are restored to 3 months control levels rats after exogenous administration of 17-β-estradiol (E2). Methods The aged rats (12 and 24 months old) (n= 8 for each group) were given subcutaneous injection of 17β estradiol (0.1 ug/g body weight) daily for one month. Controls animals received an equal volume of vehicle. After 30 days of hormone treatment, experimental animals of all the groups were sacrificed and livers were isolated for further study. A detailed study was carried on membrane linked enzymes, membrane fluidity, lipofuscin and GLUT2 expression with immunohistochemistry to identify the antiaging role of E2 using biochemical, molecular and histochemical study. Results The results obtained in the present work revealed that normal aging was associated with significant decrease in the activities of membrane-linked ATPases, antioxidant enzymes, membrane fluidity, GLUT 2 expression and an increase in lipid peroxidation and lipofuscin content in livers of aging female rats. Our data showed that exogenous administration of E2 brought these changes to near normalcy in aging female rats. Conclusions The present study showed that E2 treatment reversed the changes to normal levels. E2 treatment may be beneficial in preventing some of the age-related changes in the liver by increasing antioxidant defenses.