No effect of menstrual cycle on LDL oxidizability and particle size

Effect of exercise on oxidative stress biomarkers

Acute bouts of aerobic and anaerobic exercise can induce a state of oxidative stress, as indicated by an increase in oxidized molecules in a variety of tissues and body fluids. The extent of oxidation is dependent on the exercise mode, intensity, and duration, and is specifically related to the degree of oxidant production. Findings of increased oxidative stress have been reported for both healthy and diseased subjects following single bouts of exercise. While acute exercise has the ability to induce an oxidative stress, this same exercise stimulus appears necessary to allow for an upregulation in endogenous antioxidant defenses. This chapter presents a summary of exercise-induced oxidative stress.

Changes of markers of oxidative stress during menstrual cycle

The levels of urinary hydrogen peroxide and thiobarbituric acid reactive substances have been compared during the menstrual cycle of 12 regularly menstruating women. Higher level of both indices of oxidative stress (normalized with respect to creatinine content) were found in the luteal phase of the cycle. These results give further evidence for the usefulness of urinary hydrogen peroxide and thiobarbituric acid reactive substances as potential biomarkers of oxidative stress and for the antioxidant action of estrogens.

Menstrual cycle influences endothelial progenitor cell regulation: a link to gender differences in vascular protection?

BACKGROUND

The potential role of endothelial progenitor cells (EPCs) in the beneficial effects of estrogen on women's cardiovascular health is of great interest. We thus evaluated if menstrual cycle influences circulating levels of EPC subpopulations in normally menstruating women and if this could underline gender differences.

METHODS AND RESULTS

Ten women and ten men were recruited for this study. Peripheral blood samples were collected at each menstrual cycle phase in women and, three times over a one month period in men. Flow cytometry analysis revealed that, in women, the number of CD133+/CD34-, CD133+/CD34+ progenitor cells (PCs) and CD133+/CD34+/VEGF-R2+ EPCs per ml of blood fluctuated significantly throughout the cycle in synchronization with the level of circulating 17beta-estradiol (17betaE). Maturation of CD133+/VEGF-R2+ and CD133+/CD34-/VEGF-R2+ EPCs towards respective CD144+ advanced EPC (aEPC) subpopulations was reduced at mid-luteal phase. Greater mean global number of CD133+/CD34+ PC, CD133+/VEGF-R2+ and CD133+/CD34-/VEGF-R2+ EPC subpopulations was found in women and 17betaE was identified as a predictive factor for the gender differences perceived. Finally, maturation of CD133+ and CD133+/CD34- towards respective EPCs or aEPCs was increased in women compared to men.

CONCLUSIONS

Our results suggest a physiological regulation of the availability of PC and EPC subpopulations in premenopausal women throughout menstrual cycle and reveal gender differences in the level and maturity of specific PC, EPC and aEPC subpopulations.This cyclic regulation in premenopausal women, may in part explain the lower prevalence of cardiovascular events at middle age compared with men or the timing of such events during the menstrual cycle.