Exercise effect on oxidative stress is independent of change in estrogen metabolism.
ABSTRACT The effect of exercise training on lipid peroxidation and endogenous estrogens is not well understood in premenopausal women. Exercise effects on these variables could mediate observed associations of exercise with hormonally related cancers, including breast cancer. The purpose of the study is to determine the effect of 15 weeks of aerobic exercise on lipid peroxidation, endogenous estrogens, and body composition in young, healthy eumenorrheic women.
Fifteen sedentary premenopausal women (18-25 years) participated. Pre- and post-exercise training urine collection (three 24-h samples) started 48 h after most recent exercise session for analysis of a marker of lipid peroxidation (F(2)-isoprostane) and endogenous estrogens, including 2-hydroxyestrogens, 4-hydroxyestrogens, 16-alpha-hydroxyestrone, and ratios of these metabolites (2:16, 2:4). Body composition was measured by dual-energy X-ray absorptiometry, and F(2)-isoprostanes and estrogens were measured by gas chromatography-mass spectrometry.
Aerobic exercise resulted in a 34% decrease in F(2)-isoprostane (P = 0.02), a 10% increase in fitness (P = 0.004), a 1.2 kg decrease in body mass (P = 0.007), and a 1.8 kg decrease in fat mass (P = 0.04). No significant changes were noted in estrogens.
The effect of exercise training on oxidative stress may be relevant to risk for hormonally related cancers.
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ABSTRACT: Background: Lifetime physical activity (PA) is associated with decreased breast cancer (BC) risk; reports suggest that PA during adolescence contributes strongly to this relationship. PA lowers production of sex hormones, specifically estradiol, or decreases insulin resistance (IR), thereby lowering risk. Overweight Latina adolescents are insulin resistant and exhibit low levels of PA, potentially increasing their future BC risk. Methods: 37 obese Latina adolescents (15.7 ± 1.1 yrs) provided measures of PA using accelerometry; plasma follicular phase estradiol, sex-hormone binding globulin, total and free testosterone, dehydroepiandrosterone-sulfate (DHEAS); IR using HOMA-IR; and body composition via DEXA. Partial correlations and stepwise linear regressions assessed cross-sectional relationships between sex hormones, IR and PA. Body composition, and age were included a priori as covariates. Results: Estradiol was negatively associated with accelerometer counts per minute (CPM; r = -0.4; P = .02), percent time spent in moderate PA (%MPA; r = -0.5; P = .006), and percent time in moderate or vigorous PA (%MVPA; r = -0.5; P = .007). DHEAS was positively associated with CPM (r = .4, P = .009), %MPA (r = .3, P = .04), and %MVPA (r = .3, P = .04). Other sex hormones and IR were not associated with PA measures. Conclusion: This study is the first to show that higher habitual PA was inversely associated with estradiol in obese adolescents.Journal of Physical Activity and Health 07/2013; 10(5):727-33. · 1.95 Impact Factor
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ABSTRACT: This experimental study aimed to determine the effects of the combined application of regular exercises and massage on the values of Malondialdehyde (MDA), Nitric Oxide (NOx), Glutathione (GSH), Adenosine Deaminase (ADA) and Superoxide Dismutase (SOD). Twenty five sedentary women (32–50 years) who did not have the habit of getting regularly massages or exercising and participated voluntarily in the study. The subjects were randomly separated into three groups: control group (CG, n=9), exercise group (EG, n=8), and massage and exercise group (MEG, n=8). The basic result of this study was that a statistically significant decrease was observed in the post-test MDA values of both EG and MEG subjects. Moreover, when the GSH and SOD values are compared to CG, a statistically significant increase was determined in the values of both EG and MEG. As a result, the findings show that regular physical activities and massage manipulations significantly decrease MDA, increase SOD and GSH activities, and result in no change in NOx and ADA activities supports the assumption that regular physical activity has positive health effects.Indian journal of physiology and pharmacology 10/2013; 57(4):378-383.
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ABSTRACT: Oxidation of meat occurs under postmortem conditions and is inevitable. This oxidation includes the biochemical changes in meat leading to changes in color pigments and lipids. As a consequence, color deteriorates, and undesirable flavors and rancidity develop in meat thereby impacting on consumer appeal and satisfaction. Across carcasses, there is variation in the rate at which muscle undergoes chemical reactions under postmortem conditions that reflect inherent variation at the biochemical level. It is expected that this underlying biochemical variation will be reflected in living muscle through oxidative processes. The oxidative process of muscle tissues will vary according to an animal's immunity status, temperament, and ability to cope with stress, with all these affected by nutrition, genetics, management practices, and environmental conditions (hot and cold seasons). Identification of biomarkers that indicate the oxidative status levels of animals or muscle tissues in vivo could provide insight as to how the muscle will respond to the anoxic conditions that produce undesirable results in meat. This review outlines the potential use of 1 group of biomarkers, the isoprostanes, in the context of complex biochemical reactions relating to oxidative processes that take place in the biological systems of live animals (in vivo) and subsequently in meat (in vitro).Comprehensive Reviews in Food Science and Food Safety 09/2013; 12(5). · 3.54 Impact Factor