17β-Estradiol and Vitamin E Modulates Oxidative Stress-Induced Kidney Toxicity in Diabetic Ovariectomized Rat

Abstract

The aim of this study was to investigate the effects of vitamin E (alpha-tocopherol) and 17β-estradiol (E(2)) supplementation on malondialdehyde (MDA), glutathione (GSH), vitamin A, beta carotene, selenium-dependent glutathione peroxidase (GSH-Px), zinc-dependent superoxide dismutase (SOD), and copper/zinc-dependent catalase (CAT) values in the kidney of ovariectomized (OVX) diabetic rats. Forty-two female rats were randomly divided into seven equal groups as follows: group I, control; group II, OVX; group III, OVX+E(2); group IV, OVX+E(2)+alpha-tocopherol; group V, OVX+diabetic; group VI, OVX+diabetic+E(2); and group VII, OVX+diabetic+E(2)+alpha-tocopherol. E(2) (40 μg kg(-1)/day) and alpha-tocopherol (100 μg kg(-1)/day) were given. Bilateral ovariectomy was performed in all groups except group I. After 4 weeks, antioxidant and MDA levels in the kidney for all groups were analyzed. GSH-Px, CAT, SOD, GSH levels, vitamin A, and beta carotene levels were decreased in OVX group compared to those in the control group but MDA level was elevated via ovariectomy. However, E(2) and E(2)+alpha-tocopherol supplementations in OVX group was associated with an increase in the GSH-Px, GSH, CAT and Zn-SOD values, vitamin A, and beta carotene levels but a decrease in MDA levels in kidney. The MDA levels in the kidney of diabetic OVX rats were found higher than those in the control and OVX groups. However, GSH, GSH-Px, CAT, SOD, vitamin A, and beta carotene levels in kidney were lower in OVX diabetic rats. On the other hand, E(2) and E(2)+alpha-tocopherol supplementations to OVX diabetic rats have caused an increase in GSH-Px, CAT and SOD, GSH, vitamin A, and beta carotene levels but a decrease in MDA levels. In conclusion, the E(2) and E(2)+alpha-tocopherol supplementations to diabetic OVX and OVX rats may strengthen the antioxidant defense system by reducing lipid peroxidation, and therefore they may play a role in preventing renal disorders.

Effect of repaglinid on ovariectomy induced bone loss in rats: comparison with 17beta-estradiol

“…Celik et al (15) showed that estrogen deficiency occurring 30 days after bilateral ovariectomy in sexually adult female rats also causes changes in the bone metabolism associated with loss bone mass. In agreement with the results of previous experiments (3,4) bilateral ovariectomy in our rats was proved to be a good experimental type for postmenopausal osteoporosis.…”

Vitamin E, Vitamin C, or Losartan Is Not Nephroprotectant against Cisplatin-Induced Nephrotoxicity in Presence of Estrogen in Ovariectomized Rat Model

“…In our study, the serum level of SOD was decreased by CP (Figure 1), and it was increased when estrogen alone or in combination of estrogen and vitamin C or losartan was administered. Opposite to these findings, Ulas and Cay [69] studied diabetic rat model, and no increment of SOD was detected in estradiol plus vitamin E treated rats. The level of serum SOD in ovariectomized rats treated either by estradiol or combination of estradiol and vitamin E was reported to be higher than nontreated ovariectomized animals [71], and this supplementation reduces lipid peroxidation [69].…”

“…Losartan also has antioxidant effect, and it may improve the renal function and decrease the severity of CP-induced nephrotoxicity [5, 6]. Estrogen also has antioxidant effect [54–56], and similar to vitamin E can modulate oxidative-stress-induced kidney toxicity [69, 70]. This is while other research indicated that estrogen enhances the oxidative stress in kidney [51].…”

Gender differences in response to vitamin E and C in gentamicin induced nephrotoxicity in Wistar rats

“…This phenomenon may be due to the possible interaction of female sex hormone with antioxidant vitamins. Estradiol is an antioxidant, similar to vitamin E, which can modify oxidative stress and renal toxicity (49,50). In another study, Nematbakhsh et al have shown that in the presence of estradiol, vitamin C cannot decrease cisplatin-induced nephrotoxicity.…”

“…Also, in this study, SOD activity increased, in response to the simultaneous application of vitamins E and C (30), which is in agreement with our results among female rats. However, Ulas et al have reported that SOD activity in diabetic model rats did not have any effect on ovarectomized rats which were treated with estradiol and vitamin E, while this supplementation decreased lipid peroxidation (49). About antioxidants, other studies have shown a synergism effect on the administration of vitamin E with probucol (51) and selenium on gentamicin nephrotoxicity (25).…”