The Effects of Isoflavone Supplementation Plus Combined Exercise on Lipid Levels, and Inflammatory and Oxidative Stress Markers in Postmenopausal Women

Abstract

This study tested the effect of isoflavone supplementation in addition to combined exercise training on plasma lipid levels, inflammatory markers and oxidative stress in postmenopausal women. Thirty-two healthy and non-obese postmenopausal women without hormone therapy were randomly assigned to exercise + placebo (PLA; n = 15) or exercise + isoflavone supplementation (ISO; n = 17) groups. They performed 30 sessions of combined exercises (aerobic plus resistance) over ten weeks and consumed 100 mg of isoflavone supplementation or placebo. Blood samples were collected after an overnight fast to analyze the lipid profile, interleukin-6 (IL-6), interleukin-8 (IL-8), superoxide dismutase (SOD), total antioxidant capacity (FRAP), and thiobarbituric acid reactive substances (TBARS), before and after ten weeks of the intervention. There were no differences in the changes (pre vs. post) between groups for any of the inflammatory markers, oxidative stress markers or lipid profile variables. However, interleukin-8 was different between pre- and post-tests (p < 0.001) in both groups (Δ = 7.61 and 5.61 pg/mL) as were cholesterol levels (p < 0.05), with no interaction between groups. The combination of isoflavone supplementation and exercise training did not alter oxidative stress markers in postmenopausal women, but exercise training alone may increase IL-8 and decrease total cholesterol levels.

Effect of Plasma-Activated Water on the Microbial Decontamination and Food Quality of Thin Sheets of Bean Curd

“…Isoflavones are a group of secondary metabolites found in soybean, which play a key role in lowering cholesterol levels and preventing cancer, osteoporosis, and cardiovascular disease [26][27][28]. Therefore, the total isoflavone content is an important food quality determinant of soybean products.…”

The effects of isoflavone supplementation plus combined exercise on salivary markers of oxidative stress in postmenopausal women

“…(29) The efficiency of TBARS inhibition may depend on the individual isoflavones concentration in the extract, with some compounds having low or moderate efficiency to inhibit TBARS, (46) which may explain the slight interaction observed in this study (p = 0.037), and also why other studies found no changes in lipid peroxidation markers with ISO. (32,33) One of the main benefits from exercise training is related to improvements in antioxidant defense. In this way, we found an increase in SOD in both groups after combined exercise training indicating that this type of exercise training, independently of ISO, can improve the antioxidant activity of this enzyme in saliva.…”

“…Exercise training was performed as previously described. (32) Briefly, the exercise training consisted of 30 sessions of combined aerobic and resistance exercises during the same session. Exercise sessions took place three times per week on non-consecutive days, over 10 weeks.…”

“…(36) Lipid peroxidation levels were analyzed by the thiobarbituric acid reactive substances (TBARS) method, using a curve of 1,1,3,3-tetramethoxypropane (TMP) as the standard. (36) The salivary nitrite, catalase and total protein (TP) were measured as described by Giolo et al (32) Statistics. Results are reported as means ± SE.…”

“…(30,31) However, there are also studies that did not report any effect in oxidative markers with ISO. (32) Therefore, the objective of this study was to verify if there is an additional effect of ISO associated with combined aerobic and resistance exercise training, in salivary oxidative stress markers in postmenopausal women. Our hypothesis was that ISO together W with combined exercise performance would improve oxidative stress markers.…”