Hormone replacement therapy: relation to homocysteine and prooxidant-antioxidant status in healthy postmenopausal women

Effects of hormone replacement therapy on lens opacity, serum inflammatory cytokines, and antioxidant levels

PURPOSE

To evaluate the effect of hormone replacement therapy (HRT) on lens opacity as measured by Scheimpflug densitometry, serum inflammatory cytokines, and antioxidant levels.

METHODS

A total of 264 women who were at least five years beyond menopause were included. The control group of 128 patients (Group 1) did not use HRT at any time after menopause. The treatment group of 136 patients (Group 2) used HRT for5 years or more after menopause. Cortical, nuclear, and posterior subcapsular density; pentacam nucleus staging (PNS); pentacam densitometry of zone (PDZ) as measured using a Scheimpflug imaging system (Pentacam); and antioxidant and inflammatory cytokines activities in serum using multiplex bead analysiswere examined.

RESULTS

Uncorrected visual acuity (logMAR) of group1 was significantly worse than those of group 2 (p < .05). Group1 was significantly more myopic than group 2 (p < .05). Nuclear and posterior subcapsular density, PNS, and percentage of PDZ in group 1 were significantly higher than those of group 2 (p < .05). The serum IL-1m. IL-6, IL-8, and TGF-, concentrations of group 1 were significantly higher than those of group 2, and the serum catalase, superoxide dismutase 1 (SOD 1), and superoxide dismutase 2 (SOD 2) fluorescence intensities of group 1 were significantly lower than those of group 2 (p < .05).

CONCLUSIONS

Long-term use of HRT may have a protective effect against cataract formation. HRT seems to be effective in decreasing inflammation and increasing antioxidant contents in the serum of postmenopausal women.KEY MESSAGESHormone replacement therapy (HRT) decrease lens opacity in postmenopausal women as measured by Scheimpflug densitometry.HRT decrease serum inflammatory cytokines and increase antioxidant levelsin the serum of postmenopausal women.Long-term use of HRT may have a protective effect against cataract formationin postmenopausal women.

Oxidative damage and the pathogenesis of menopause related disturbances and diseases

The postmenopausal phase of life is frequently associated in women with subjective symptoms (e.g. vasomotor) and real diseases (atherosclerosis with coronary ischemia, osteoporosis, Alzheimer-type neurodegeneration, urogenital dystrophy), which together determine the post-menopausal syndrome. Observations that oxidative damage by reactive oxygen/nitrogen species in experimental models can contribute to the pathogenesis of these disturbances stimulated research on the relationships between menopause, its endocrine deficiency, oxidative balance and the "wellness" in postmenopausal life. The connection among these events is probably due to the loss of protective actions exerted by estrogens during the fertile life. Most recent studies have revealed that estrogens exert an antioxidant action not by direct chemical neutralization of reactants as it was expected until recently but by modulating the expression of antioxidant enzymes that control levels of biological reducing agents. Also nutritional antioxidants apparently act by a similar mechanism. From this perspective it is conceivable that a cumulative control of body oxidant challenges and biological defenses could help in monitoring between "normal" and "pathological" menopause. However, as clinical studies failed to confirm this scenario in vivo, we have decided to review the existing literature to understand the causes of this discrepancy and whether this was due to methodologic reasons or to real failure of the basic hypothesis.

Estrogen plus progestin increase superoxide dismutase and total antioxidant capacity in postmenopausal women

OBJECTIVE

This cross-sectional study aimed to evaluate the behavior of blood antioxidant enzymes (superoxide dismutase (SOD), catalase and glutathione peroxidase), plasma total antioxidant capacity and oxidative damage (lipid oxidation and protein carbonyl levels) and their relationship with the serum levels of steroid hormones in premenopausal and postmenopausal women without and with estrogen alone (ET) or estrogen plus progestin therapy (EPT).

METHODS

Blood was collected from four groups of subjects: premenopausal women (n = 24), postmenopausal women without hormone therapy (n = 31), postmenopausal women with ET (n = 12) and postmenopausal women with EPT (n = 16).

RESULTS

The activities of the different SOD isoforms (CuZnSOD and MnSOD) and the plasma total antioxidant power were significantly higher in the postmenopausal women under EPT than in the postmenopausal women without hormone replacement therapy (HRT). Only CuZnSOD activity was increased in women receiving ET compared to the postmenopausal women without HRT. However, no differences were observed in the levels of lipid or protein oxidation or in the non-enzymatic plasma antioxidants (uric acid and albumin) among the groups. The duration of HRT and serum estrogen levels were positively correlated to the blood CuZnSOD activity and to plasma total antioxidant power, whereas the serum progesterone levels were positively correlated to CuZnSOD activity and negatively correlated to protein carbonyl groups. Interestingly, the total antioxidant power of plasma was positively correlated to CuZnSOD and glutathione peroxidase activities.

CONCLUSION

We conclude that EPT increases blood MnSOD and CuZnSOD activity in postmenopausal women, leading to an increased plasma total antioxidant capacity. This finding may be relevant to the prevention of oxidative stress-related disorders in postmenopausal women.

Homocysteine as a risk factor for hypertension: a 2-year follow-up study

Homocysteine (Hcy) is regarded as a risk factor for hypertension, but research on the causal relationship between Hcy and hypertension is limited. In the present study, we prospectively tracked the blood pressure progression of a normotensive population with different Hcy levels over a 2-year period. The incidence of hypertension with increasing Hcy quartiles produced an approximately U-shaped curve, with significance in males. Compared with the third quartile, the risk of hypertension in the first and second quartiles was increased by 1.55 (95% confidence interval [CI] 1.154–2.081) fold and 1.501 (95% CI 1.119–2.013) fold, respectively, with the increase being more significant in males. In conclusion, Hcy is related to hypertension incidence with the results approximating an U-shaped curve. Low Hcy levels might also increase the risk of hypertension.

More than hormones: sex differences in cardiovascular parameters after sleep loss in rats

Although the influence of sex on sleep pattern and cardiovascular parameters is well known, knowledge regarding the effects of sleep loss on heart responses in both sexes is scarce. The present study investigated the effects of paradoxical sleep deprivation (PSD) and chronic sleep restriction (SR) on cardiovascular parameters and adrenocorticotropic hormone (ACTH) levels in male and female rats. Both groups were randomly assigned to PSD for 96 h, SR for 21 days or home-cage control. Mean arterial pressure (MAP), heart rate (HR), baroreflex sensitivity (bradycardia and tachycardia responses) and ACTH levels were evaluated. The results showed that PSD induced a significant increase in HR and ACTH levels in both sexes, although male rats presented higher levels of ACTH hormone compared to females. In addition to sex-specific responses, PSD decreased the tachycardia only in male rats. SR, induced a significant increase in MAP and decrease in bradycardia in both sexes. Male rats were more affected by sleep deprivation protocols than females for MAP, bradycardia response, and ACTH levels. The results showed that the effects of sleep loss on cardiovascular parameters are associated with the protocol of sleep deprivation and that sex can modulate these effects. We suggested this experimental model as a suitable tool for further investigations of the relationship between cardiovascular parameters and sleep.