γ-Glutamyl transferase as a marker of oxidative stress in pre and post-menopausal women

Abstract

Introduction: Menopause is a physiologic process in women representing complete cessation of menstruation and gradual decrease of estrogen secretion. The antioxidant substances present in the body play a role in combating the oxidative stress in menopause. Since, the enzyme γ-glutamyl transferase plays an important role in the metabolism of the endogenous antioxidant reduced glutathione (GSH), it can reflect the antioxidant ability in vivo. Aim: The present study was conducted to investigate γ-glutamyl transferase as a possible marker of total antioxidant capacity (TAC) of plasma. Materials and Method: The study included 50 female volunteers, selected from medical & paramedical staff, and healthy attendants of patients as per inclusion and exclusion criteria and divided into 2 groups. Group I: Premenopausal women (n = 25); Group II: Postmenopausal women (n = 25). Venous blood samples were collected using aseptic techniques in plain vials for estimating estradiol hormone and Gamma GT and whole blood was collected in EDTA vials for the estimation of Ferric reducing ability of plasma (FRAP) which is a marker of antioxidant capacity. The data collected were analyzed using unpaired “t”-test for evaluating the level of oxidative stress in pre and post menopausal women and the variations in the levels of gamma GT in the two groups. The results were expressed as Mean ± Standard Deviation (SD). Results and Conclusion: Depressed estrogen synthesis in postmenopausal women enhanced oxidative stress and lead to deficit of total antioxidant capacity of plasma. A significant increase in serum GGT in the post-menopausal group relative to the pre-menopausal group was found which was to compensate and correct the reduced glutathione levels by increasing its biosynthesis. Thus, GGT can be used as a marker of total antioxidant capacity of plasma and oxidative stress.