A combination of soy isoflavone supplementation and exercise improves lipid profiles and protects antioxidant defense‐systems against exercise‐induced oxidative stress in ovariectomized rats

Abstract

Menopause is often accompanied with weight gain, metabolic lipid abnormalities, and oxidative stress. In this study, we investigated the combined effects of exercise and soy isoflavone supplementation on the lipid profiles and antioxidant capacities of ovariectomized rats. Twenty-five female Sprague-Dawley rats were divided into 5 groups: sham-operated, ovariectomized (OVX), OVX with exercise (OVX+EX), OVX with soy isoflavone supplementation (OVX+ISO), and OVX with both soy isoflavones and exercise (OVX+ISO+EX). After 12 weeks of intervention, antioxidant status was evaluated in collected blood samples by the ferric reducing ability of plasma (FRAP), glutathione (GSH) content, and sodium oxide dismutase (SOD) activity. DNA damage in the lymphocytes was determined using alkaline single-cell gel electrophoresis (the Comet assay). Although there were no significant differences in weight gain and food intake, weight gain was lower in OVX+EX, OVX+ISO, and OVX+ISO+EX than in OVX. OVX+EX, OVX+ISO, and OVX+ ISO+EX showed a significant decrease in total cholesterol, triglycerides, and LDL-cholesterol compared to OVX. The soy isoflavone supplemented group had significantly increased FRAP values and GSH contents in contrast to no changes in the exercised group, whereas exercise markedly increased SOD activity and H2O2-induced DNA tail length and tail moment. Exercise with soy isoflavone supplementation significantly increased FRAP values and had no difference on SOD activity, including DNA damage. These results demonstrate that a combined treatment of moderate exercise and soy isoflavone supplementation could exert a beneficial effect on weight control and lipid profiles, and offer protection from exercise-induced oxidative stress in postmenopausal women.

Combined Effects of Six Weeks Oat Bran Consumption and Brisk Walking Exercise on Blood Lipid Profiles in Hypercholesterolemia Women Aged 40 to 50 Years

“…In the present study, 6 weeks of combined oat bran with brisk walking exercise could reduce serum total cholesterol and LDL-C concentrations. Both Oh et al 19 and the present study showed that combined exercise and nutritional supplementation could give beneficial effect on improving lipid profiles. Nevertheless, comparison between Oh et al 19 and the present study showed that shorter study period as in the present study could only reduce total cholesterol and LDL-C, but not triglycerides as reported by Oh et al 19 Therefore it is recommended for lengthening the study duration in future in order to get better results, it is speculated that participants may need longer time to adapt to the exercise and supplementation physiologically.…”

“…[18][19][20] According to animal study by Oh et al, 19 combination of soy supplementation and exercise showed its effectiveness by lowering serum total cholesterol, triglycerides and LDL-C in rats. To date, information are lacking on the additional beneficial of combined effects of brisk walking and oat bran consumption compared to oat bran consumption alone and sedentary without consumption of oat bran on body weight, body composition and blood lipid profiles among hypercholesterolemia women aged 40-50 years old.…”

“…Oh et al 19 demonstrated that combined treadmill running exercise for 30 minutes with supplementation of soy isofalvone lowered serum total cholesterol, triglycerides and LDL-C after 12 weeks of intervention. In the present study, 6 weeks of combined oat bran with brisk walking exercise could reduce serum total cholesterol and LDL-C concentrations.…”

Serum cholesterol and expression of ApoAI, LXRβ and SREBP2 in vitamin D receptor knock-out mice

“…Cholesterol changes in postmenopausal women [54] and in rodents after ovariectomy [55,56] are due to a lack of estrogen. Kamei et al [57] identified changes of gene expression in lipid metabolism including a decrease of SREBP1 in ovariectomized mice.…”

Combined treatment of isoflavone supplementation and exercise restores the changes in hepatic protein expression in ovariectomized rats - a proteomics approach

“…Our group has previously reported that ovariectomized rats that underwent an exercise intervention had significantly elevated DNA damage in their lymphocytes compared to those that did not receive exercise [23]. Therefore, even if exercise interventions could lower blood LDL-cholesterol and the atherogenic index, the exercise may need to be monitored to minimize possible DNA damage in cases of estrogen deficiency [23].…”