Decline in endothelial function across the menopause transition in healthy women is related to decreased estradiol and increased oxidative stress

Unveiling the role of exercise in modulating plasma heat shock protein 27 levels: insights for exercise immunology and cardiovascular health

Cardiovascular disease is one of the leading causes of mortality worldwide, primarily driven by atherosclerosis, a chronic inflammatory condition contributing significantly to fatalities. Various biological determinants affecting cardiovascular health across different age and sex groups have been identified. In this context, recent attention has focused on the potential therapeutic and preventive role of increasing circulating levels of heat shock protein 27 (plasma HSP27) in combating atherosclerosis. Plasma HSP27 is recognized for its protective function in inflammatory atherogenesis, offering promising avenues for intervention and management strategies against this prevalent cardiovascular ailment. Exercise has emerged as a pivotal strategy in preventing and managing cardiovascular disease, with literature indicating an increase in plasma HSP27 levels post-exercise. However, there is limited understanding of the impact of exercise on the release of HSP27 into circulation. Clarifying these aspects is crucial for understanding the role of exercise in modulating plasma HSP27 levels and its potential implications for cardiovascular health across diverse populations. Therefore, this review aims to establish a more comprehensive understanding of the relationship between plasma HSP27 and exercise.

Oxidative stress suppresses internal carotid artery dilation to hypercapnia in healthy older adults

Cerebrovascular disease and dementia risk increases with age, and lifetime risk is greater in women. Cerebrovascular dysfunction likely precedes cerebrovascular disease and dementia but the mechanisms are incompletely understood. We hypothesized that oxidative stress mediates cerebrovascular dysfunction with human aging. Internal carotid artery dilation (ICACO2 dilation) and middle cerebral artery cerebrovascular reactivity (MCA CVRCO2) in response to hypercapnia (5% CO2) were measured in 20 young [10 F/10 M; age 23 ± 3 yr (means ± SD)] and 21 older (11 F/10 M; age 69 ± 9 yr) adults during intravenous infusions of saline (control) and vitamin C (acutely reduced oxidative stress condition). ICACO2 dilation increased in response to vitamin C infusion in older adults (saline = 4.3 ± 2.4%; vitamin C = 6.7 ± 3.3%) but was unchanged in young adults (saline = 6.1 ± 2.7%; vitamin C = 5.5 ± 1.9%) (group × condition: P = 0.004). MCA CVRCO2 was not different in response to vitamin C in either group (group × condition: P = 0.341). However, when separated by sex, older female participants exhibited increased MCA CVRCO2 with vitamin C (saline = 0.85 ± 0.79 cm/s/mmHg; vitamin C = 1.33 ± 1.01 cm/s/mmHg) compared with older male participants (saline = 1.21 ± 0.57 cm/s/mmHg; vitamin C = 0.99 ± 0.47 cm/s/mmHg) (sex × condition: P = 0.011). Oxidative stress selectively impairs cerebrovascular function in older adults in an artery- and sex-specific manner.NEW & NOTEWORTHY This study is the first to report oxidative stress-mediated suppression of cerebrovascular reactivity to hypercapnia in the internal carotid artery in older compared with young adults. Overall, these in vivo findings identify oxidative stress as an important pathophysiological contributor to cerebrovascular aging in humans, highlighting the need to identify novel interventions that can reduce oxidative stress in the aging population.

Preservation of Vascular Endothelial Function in Late-Onset Postmenopausal Women

BACKGROUND

Postmenopausal women (PMW) who complete menopause at a late age (55+ years) have lower cardiovascular disease risk than PMW who complete menopause at a normal age (45-54 years). However, the influence of late-onset menopause on vascular endothelial dysfunction is unknown. Moreover, the mechanisms by which a later age at menopause may modulate endothelial function remain to be determined.

METHODS

We measured endothelial function (brachial artery flow-mediated dilation [FMDBA]) in age-matched late- and normal-onset PMW and a young premenopausal reference group. We determined mitochondrial reactive oxygen species (mitoROS)-related suppression of endothelial function (change in FMDBA with an acute dose of the mitochondria-targeted antioxidant MitoQ; ΔFMDBA, MTQ) in PMW. The effects of serum from late- and normal-onset PMW and premenopausal women on mitoROS bioactivity in human aortic endothelial cells in culture were assessed. Metabolomics analyses in combination with serum metabolite level normalization and human aortic endothelial cell serum exposure experiments were performed to identify the circulating factors contributing to the serum effects on endothelial cell mitoROS bioactivity.

RESULTS

FMDBA in PMW was lower than in premenopausal women. However, FMDBA was >50% higher in late- versus normal-onset PMW and positively related to age at menopause. ΔFMDBA, MTQ was >50% lower in late- versus normal-onset PMW. Serum from normal-onset PMW but not late-onset PMW induced higher mitoROS bioactivity in human aortic endothelial cells compared with serum from premenopausal women. mitoROS bioactivity was negatively related to FMDBA and age at menopause. Seventeen metabolites significantly differed between late- and normal-onset PMW; 15 were lipid specific; 8 were triglyceride derived. TG(16:0) was most strongly correlated with mitoROS bioactivity. Normalization of TG(16:0) concentrations in serum from premenopausal women and late-onset PMW to match serum levels in normal-onset PMW abrogated differences in mitoROS bioactivity in serum-treated human aortic endothelial cells.

CONCLUSIONS

Late-onset menopause is associated with preservation of endothelial function, which is mediated by lower mitoROS-associated oxidative stress. A more favorable profile of circulating lipid metabolites, specifically triglyceride-derived metabolites, contributes to lower endothelial cell mitoROS in late-onset PMW. These findings provide new insight into the possible mechanisms of reduced cardiovascular disease risk in late-onset menopause.

Vascular health and exercise in females throughout the lifespan: Exploring puberty, pregnancy and menopause

This narrative review highlights the impact of exercise on vascular health in females over the lifespan with an emphasis on puberty, pregnancy and menopause. These events encompass substantial changes in sex hormone levels, particularly oestrogens and progesterone. They are also accompanied by distinct adaptations of the central, peripheral and cerebral vasculature. Regular exercise is an effective mechanism to reduce vascular risk in females of all ages, especially for those at higher risk for vascular disorders. However, there are large variabilities in the vascular adaptations to exercise in females that may be related to circulating sex hormone levels. In addition, exogenous hormones, such as oral contraceptives taken after puberty or hormonal replacement therapy taken to mitigate symptoms of menopause, may interact with exercise-induced changes in vascular function. We highlight how more research is needed to understand the optimal exercise interventions to promote vascular health in females across the lifespan, especially during times of hormonal transition.

The Effects of Previous Amenorrhea on Endothelial and Vascular Function

Introduction: Endogenous estrogen has a protective cardiovascular effect. Estrogen loss, such as during menopause and amenorrhea, results in stiffer vessels and endothelial dysfunction. It is unknown if reversing amenorrhea and regaining a regular menstrual cycle leads to the restoration of cardiovascular function. Methods: Sixteen women were divided into groups: eumenorrheic (n = 10; 23 ± 3 years) women who had a consistent menstrual cycle and amenorrheic (n = 6; 22 ± 1 year) women who previously were without their menstrual cycle for at least 6 consecutive months. Endothelial function, arterial stiffness, and brachial and aortic blood pressure were assessed. Results: There were no differences between groups in endothelial function or arterial stiffness measures. The previously amenorrheic group displayed lower brachial systolic and mean pressures and aortic systolic, diastolic, and mean pressures. When controlling for physical activity, only central pressure remained significantly lower in the amenorrheic group. Conclusions: Previous amenorrhea in young women does not result in long-term cardiovascular consequences in arterial and endothelial function measures assuming regular menstruation resumes. Physical activity shows a blood pressure-lowering effect in the peripheral arteries, while the previously amenorrheic group demonstrated lower central pressures, independent of physical activity.

Prevention of cardiovascular disease in women with type 2 diabetes: the role of incretin mimetics and sodium-glucose cotransporter-2 inhibitors

Cardiovascular disease (CVD) is the leading cause of death among individuals with type 2 diabetes (T2D), with women experiencing a disproportionate risk of events compared with men. Women have an amplified burden of cardiovascular risk factors once T2D is diagnosed. Incretin mimetics now plays a central role in managing cardiovascular risk by improving glycemic control, promoting weight loss, and potentially exerting direct cardioprotective effects. Similarly, sodium-glucose cotransporter-2 inhibitors contribute to CVD prevention through various nonglucose-lowering mechanisms. Both classes of medications are integral to personalized treatment strategies aimed at addressing the heightened cardiovascular risk faced by women with diabetes. This mini-review addresses possible mechanisms underlying the increased cardiovascular risk and explores the role of incretin mimetics and SGLT2 inhibitors in mitigating CVD in women with T2D. Emphasizing personalized and sex-specific approaches in diabetes care is crucial for optimizing treatment outcomes and improving cardiovascular health.

Physical Activity and Arterial Stiffness: A Narrative Review

Arterial stiffness is a significant predictor of cardiovascular disease and mortality. Physical activity (PA) has been extensively studied for its potential to reduce arterial stiffness, but the relationship between different types, durations, and intensities of PA and arterial stiffness remains a topic of ongoing research. Therefore, in this narrative review, we evaluated the current evidence focusing on the effect of PA on arterial stiffness and vascular health and discussed the known underlying physiological mechanisms. PA, irrespective of its intensity or pattern, is consistently associated with lower arterial stiffness. Aerobic exercise, particularly at higher intensities, is the most effective strategy for reducing arterial stiffness. These benefits are especially significant in populations with higher cardiovascular risk, such as those with type 2 diabetes mellitus and hypertension. Therefore, maintaining an active lifestyle into older age is crucial for vascular health and may contribute to healthy aging.

Modulation of Vascular Health by Hormonal Contraceptives and Exercise in Young Women: Using the FITT Principles Methodological Framework

Cardiovascular health is governed by responses of the heart and vasculature to stimuli, including exercise and synthetic hormones in hormonal contraception. In this review, we draw similarities between research examining the effects of exercise training and hormonal contraception on vascular health, aligned using FITT principles (frequency, intensity, type, and time) as a methodological framework, and outline future directions for research.

Functional Foods and Nutraceuticals for the Management of Cardiovascular Disease Risk in Postmenopausal Women

Cardiovascular disease (CVD) is a leading cause of death in women and risk of development is greatly increased following menopause. Menopause occurs over several years and is associated with hormonal changes, including a reduction in estradiol and an increase in follicle-stimulating hormone. This hormonal shift may result in an increased risk of developing abdominal adiposity, insulin resistance, dyslipidemia, vascular dysfunction, hypertension, type 2 diabetes mellitus (T2DM), metabolic dysfunction-associated fatty liver disease (MAFLD), and metabolic syndrome (MetS). Furthermore, with the onset of menopause, there is an increase in oxidative stress that is associated with impaired vascular function, inflammation, and thrombosis, further increasing the risk of CVD development. Despite the harmful consequences of the menopause transition being well known, women in premenopausal, perimenopausal, and postmenopausal stages are unlikely to be enrolled in research studies. Therefore, investigations on the prevention and treatment of cardiovascular and metabolic disease in middle-aged women are still relatively limited. Whilst lifestyle interventions are associated with reduced CVD risk in this population sample, the evidence still remains inconclusive. Therefore, it is important to explore the effectiveness of early intervention and potential therapeutic approaches to maintain cellular redox balance, preserve endothelium, and reduce inflammation. Glycine, N-acetylcysteine, and L-theanine are amino acids with potential antioxidant and anti-inflammatory activity and are identified as therapeutic interventions in the management of age-related and metabolic diseases. The benefits of the intake of these amino acids for improving factors associated with cardiovascular health are discussed in this review. Future studies using these amino acids are warranted to investigate their effect on maintaining the vascular health and cardiovascular outcomes of postmenopausal women.

Menstrual cycle and the protective effects of remote ischemic preconditioning against endothelial ischemia/reperfusion injury: comparison with postmenopausal women

The aim of this study was to determine whether the capacity of remote ischemic preconditioning (IPC) against endothelial ischemia/reperfusion (I/R) injury changes across the menstrual cycle in premenopausal women and to compare IPC responses to postmenopausal women. Thirty-five women were studied (22 premenopausal/13 postmenopausal). Changes in endothelial function were determined during the early follicular vs. the late follicular phase (after positive urine ovulation test; Study 1), vs. the mid-luteal phase (after positive urine progesterone test; Study 2), and vs. estrogen-deficient postmenopausal women; Study 3). Endothelium-dependent vasodilation was assessed by the forearm blood flow (FBF) to reactive hyperemia with/without I/R injury with remote IPC (3 × 5 min cycles of upper arm ischemia). In the premenopausal women, peak FBF responses during the early follicular phase were blunted 20% (P < 0.0001) with I/R injury (from baseline: 23.4 ± 6.2 to 19.5 ± 4.9 mL/100 mL tissue/min) compared with the late follicular/mid-luteal phases despite IPC. In postmenopausal women, peak FBF was diminished (from: 21.1 ± 5.1 to 17.2 ± 4.4 mL/100 mL tissue/min), and total FBF (area under the curve) was decreased a third (-32%; P < 0.001) with I/R injury. Protection from I/R injury was preserved during the late follicular (from baseline: 21.7 ± 5.3 to 24.8 ± 5.9 mL/100 mL tissue/min; P = 0.109) and mid-luteal phases (from: 25.1 ± 3.9 to 27.2 ± 5.7 mL/100 mL tissue/min; P = 0.267). Reduced estrogen during the early follicular phase and the rise in estrogen associated with ovulation and the mid-luteal phase may contribute to changes in IPC-mediated protection in premenopausal women and shed light on how cardioprotection may change with ovarian hormone deficiency with the menopause transition.NEW & NOTEWORTHY The capacity of remote ischemic preconditioning to protect against vascular endothelial ischemia/reperfusion injury varies widely across the phases of the menstrual cycle in healthy premenopausal women. Robust protection was afforded during the late follicular and mid-luteal phases. In contrast, weakened protection was demonstrated during the early follicular phase, with a level of impairment similar to estrogen-deficient postmenopausal women.

Peripheral arterial disease in women

Peripheral arterial disease (PAD) represents one of the most frequent manifestations of atherosclerosis in men and women. In both sexes, PAD is related to classical risk factors of atherosclerosis, which are similarly distributed, but some additional factors determine differences between men and women. More frequent asymptomatic disease in women than in men and less frequent screening in women may result in a false underestimation of the prevalence of PAD in women. All these factors may cause delayed diagnosis and treatment of PAD in women. Estrogen hormones have vasoprotective properties that lower the prevalence of atherosclerosis in women of younger age. However, estrogen probably does not have a protective role against the development of cardiovascular disease in women of an older age. Hormone replacement therapy (HRT) of less than one year does not appear to reduce the odds of developing PAD in postmenopausal women. It may even increase the risk of morbidity from vascular interventions. However, some studies indicated that HRT for more than one year significantly decreases the risk of PAD if administered early after the last menstruation. Also, treatment of PAD in women differs to some extent from men.

Characterizing vascular and hormonal changes in women across the life span: a cross-sectional analysis

Vascular dysfunction, marked by lower endothelial function and increased aortic stiffness, is a nontraditional risk factor that precedes the development of cardiovascular disease (CVD). However, the age at which these changes in vascular function occur in women and the degree to which reproductive hormones mediate these changes has not been characterized. Women free from major disease were enrolled across the adult life span (aged 18-70 yr, n = 140). Endothelial function was assessed as flow-mediated dilation (FMD) of the brachial artery during reactive hyperemia using duplex ultrasound and expressed as percent dilation. Aortic stiffness was measured by carotid-femoral pulse wave velocity (cfPWV). Blood samples were obtained to quantify reproductive hormone concentration. Regression models determined age-related breakpoints and mediating factors between age and vascular outcomes. FMD declined with age with a breakpoint and steeper decline occurring at 47 yr of age. Thereafter, age was independently associated with lower FMD (B = -0.13, P < 0.001). cfPWV was relatively stable until a breakpoint at age 48, and age was independently associated with higher cfPWV thereafter (B = 0.10, P < 0.001). Path analysis revealed that the association between age and FMD was partially mediated by follicle-stimulating hormone (abind = 0.051, P = 0.01) and progesterone (abind = 0.513, P < 0.001) but not estradiol (abind = -0.004, P = 0.08). No mediation was present for cfPWV. Age was associated with endothelial dysfunction and aortic stiffness in women beginning at 47 and 48 yr old, respectively, 3 to 4 yr before the average age of menopause. The association between age and endothelial dysfunction was explained in part by elevations in follicle-stimulating hormone and progesterone, but not declining estradiol.NEW & NOTEWORTHY We demonstrate that the age at which endothelial function declines and aortic stiffness increases in healthy women is 47 and 48, respectively. The inflection point in flow-mediated dilation (FMD) is 6 yr earlier than previously reported, and the association between age and FMD was mediated by follicle-stimulating hormone (FSH) and progesterone (P4) but not estradiol (E2).

Endothelial and exercise vasodilation are reduced in postmenopausal females with obesity versus lean and overweight

BACKGROUND

Obesity (OB) is highly prevalent in females after menopause, especially visceral adipose tissue (VAT) accumulation which contributes to endothelial dysfunction. The endothelium assists in regulating blood flow (BF) during exercise and is attenuated in females with OB. The purpose of this study was to examine upper and lower limb flow-mediated dilation (FMD) and BF regulation during graded low-intensity submaximal exercises in postmenopausal females with BMI in the lean (LN), overweight (OW) and OB categories.

METHODS

Participants were grouped by body mass index (BMI) into LN (BMI 18.5-24.9 kg/m2; n = 11), OW (BMI 25.0-29.9 kg/m2; n = 15), and OB (BMI 30.0-39.9 kg/m2; n = 13). FMD of the brachial (BA-FMD) and superficial femoral arteries (FA-FMD) were assessed. Subsequently, BF and vascular conductance (VC) in the upper (BA-BF and BA-VC) and lower limbs (FA-BF and FA-VC) were measured during separate 3-stage incremental rhythmic handgrip and plantarflexion exercises.

RESULTS

Significantly lower FA-FMD (P < 0.05) were seen in OB than LN and OW groups with no differences in BA-FMD. Increases in FA-BF and FA-VC were attenuated during the last stage of plantarflexion exercise at 30% of 1RM in OB (both P < 0.001) compared to LN and OW, while upper-body exercise vasodilation was unchanged. FA-BF and FA-VC during plantarflexion exercise were correlated to FA-FMD (FA-BF: r = 0.423, P = 0.007, FA-VC: r = 0.367, P = 0.021) and BMI (FA-BF: r = -0.386, P = 0.015, FA-VC: r = -0.456, P = 0.004).

CONCLUSION

Postmenopausal females with OB have reduced lower-limb endothelial and exercise vasodilator function during submaximal dynamic plantarflexion exercise compared to LN and OW. Our findings indicate that obesity may predict diminished leg endothelial function, BF and VC during exercise in postmenopausal females.

The acute effects of dietary nitrate supplementation on postmenopausal endothelial resistance to ischemia reperfusion injury: a randomized, placebo-controlled, double blind, crossover clinical trial

Postmenopausal cardiovascular health is a critical determinant of longevity. Consumption of beetroot juice (BR) and other nitrate-rich foods is a safe, effective non-pharmaceutical intervention to increase systemic bioavailability of the vasoprotective molecule, nitric oxide, through the exogenous nitrate (NO3 -)-nitrite (NO2 -)-nitric oxide (NO) pathway. We hypothesized that a single dose of nitrate-rich beetroot juice (BRnitrate 600 mg NO3 -/140 mL, BRplacebo ∼ 0 mg/140 mL) would improve resting endothelial function and resistance to ischemia-reperfusion (IR) injury to a greater extent in early-postmenopausal (1-6 years following their final menstrual period (FMP), n = 12) compared to late-postmenopausal (6+ years after FMP, n = 12) women. Analyses with general linear models revealed a significant (p < 0.05) time*treatment interaction effect for brachial artery adjusted flow-mediated dilation (FMD). Pairwise comparisons revealed that adjusted FMD was significantly lower following IR-injury in comparison to all other time points with BRplacebo (early FMD 2.51 ± 1.18%, late FMD 1.30 ± 1.10, p < 0.001) and was lower than post-IR with BRnitrate (early FMD 3.84 ± 1.21%, late FMD 3.21 ± 1.13%, p = 0.014). A single dose of BRnitrate significantly increased resting macrovascular function in the late postmenopausal group only (p = 0.005). Considering the postmenopausal stage-dependent variations in endothelial responsiveness to dietary nitrate, we predict differing mechanisms underpin macrovascular protection against IR injury.

A clinical trial of the effects of cocoa rich chocolate on depression and sleep quality in menopausal women

In this triple-blind, randomized clinical trial, 60 menopausal women between the ages of 45 and 65 were randomized to receive 78% dark chocolate (12 g/day) or milk chocolate (12 g/day) for eight weeks. The primary outcome was depression scores. Secondary outcomes included sleep quality and anthropometric indices. ANCOVA with baseline adjustment showed that the mean depression score after the intervention in the group receiving dark chocolate was significantly reduced compared to the milk chocolate group (mean difference: -2.3; 95% confidence interval: -3.9 to -0.8; p = 0.003; Cohen's d = -0.54). However, no statistically significant difference in the overall sleep quality score and its subdomains was observed between the two groups after the intervention (p > 0.05). Furthermore, after the intervention, there was no statistically significant difference between the two groups in terms of anthropometric indices, including weight (p = 0.075), BMI (p = 0.137), waist circumference (p = 0.463), and hip circumference (p = 0.114). The study suggests that consuming 78% dark chocolate for eight weeks may contribute to improvements in depression scores, but it does not appear to improve sleep quality or anthropometric indices.Trial registration: IRCT20220926056046N1; December 2022.

Sex-specific effects of intensity and dose of physical activity on BOLD-fMRI cerebrovascular reactivity and cerebral pulsatility

Cerebrovascular reactivity (CVR) and cerebral pulsatility (CP) are important indicators of cerebrovascular health and have been shown to be associated with physical activity (PA). Sex differences have been shown to influence the impact of PA on cerebrovascular health. However, the sex-specific effects of PA on CP and CVR, particularly in relation to intensity and dosage of PA, remains unknown. Thus, this cross-sectional study aimed to evaluate the sex-specific effects of different intensities and doses of PA on CVR and CP. The Human Connectome - Aging dataset was used, including 626 participants (350 females, 276 males) aged 36-85 (mean age: 58.8 ± 14.1 years). Females were stratified into premenopausal and postmenopausal groups to assess the potential influence of menopausal status. Novel tools based solely on resting state fMRI data were used to estimate both CVR and CP. The International Physical Activity Questionnaire was used to quantify weekly self-reported PA as metabolic equivalent of task. Results indicated that both sexes and menopausal subgroups revealed negative linear relationships between relative CVR and PA. Furthermore, females presented a unique non-linear relationship between relative CVR and total PA in the cerebral cortex. In females, there were also relationships with total and walking PA in occipital and cingulate regions. In males, we observed relationships between total or vigorous PA and CVR in parietal and cingulate regions. Sex-specific effects were also observed with CP, whereby females benefited across a greater number of regions and intensities than males, especially in the postmenopause group. Overall, males and females appear to benefit from different amounts and intensities of PA, with menopause status significantly influencing the effect of PA on cerebrovascular outcomes, underscoring the need for sex-specific recommendations in promoting cerebrovascular health.

Acute impact of inorganic nitrate supplementation after ischemia and during small muscle mass exercise in postmenopausal females: A pilot study

Menopause is associated with reduced endothelial-dependent vasodilation and increased cardiovascular disease (CVD) risk. Dietary nitrate, a non-pharmacological approach, may increase vasodilatory capacity consequentially reducing CVD risk. We investigated macro- and microvascular function after acute nitrate supplementation in postmenopausal females (PMF). Vascular function was studied with flow-mediated vasodilation (FMD) and near-infrared post occlusive reactive hyperemia (PORH). Incremental handgrip exercise was performed to investigate blood flow and tissue oxygenation. We hypothesized acute dietary nitrate would not impact resting endothelial measures but would increase post ischemic vasodilation and incremental exercise blood flow. Late-phase PMF (n = 12) participated in a randomized crossover design with 140 mL of nitrate-rich (NR) beetroot juice or nitrate-poor black currant juice. Testing included a 5-min FMD, a 3-min ischemic exercise FMD, and incremental exercise at 10%, 15%, and 20% maximal voluntary contraction to measure blood flow and pressure responses. A p ≤ 0.05 was considered significant. One-way ANOVA indicated lower resting pressures, but no change to FMD, or PORH in either protocol. Two-way repeated measures ANOVA indicated NR supplementation significantly reduced mean arterial pressure at rest and during incremental exercise at all intensities without changes to blood flow. Acute nitrate is effective for resting and exercising blood pressure management in PMF.

Estrone-mediated lowering of ROS and NOX4 improves endothelial function in ovariectomized wistar rats

Estrone (E1) constitutes the primary component in oral conjugated equine estrogens (CEEs) and serves as the principal estrogen precursor in the female circulation in the post-menopause. E1 induces endothelium-dependent vasodilation and activate PI3K/NO/cGMP signaling. To assess whether E1 mitigates vascular dysfunction associated with postmenopause and explore the underlying mechanisms, we examined the vascular effects of E1 in ovariectomized (OVX) rats, a postmenopausal experimental model. Blood pressure was measured using tail-cuff plethysmography, and aortic rings were isolated to assess responses to phenylephrine, acetylcholine (ACh), and sodium nitroprusside. Responses to ACh in rings pre-incubated with superoxide dismutase (SOD), catalase (CAT), or apocynin were also evaluated. Protein expression of SOD, CAT, NOX1, NOX2, and NOX4 was determined by Western blotting. E1 treatment resulted in decreased body weight and retroperitoneal fat, increased uterine weight, and prevented elevated blood pressure in the OVX group. Furthermore, E1 improved endothelium-dependent ACh vasodilation, activated compensatory antioxidant mechanisms - i.e. increased SOD and CAT antioxidant enzymes activity, and decreased NOX4 expression. This, in turn, helped prevent oxidative stress and endothelial dysfunction in OVX rats. Additionally, E1 treatment reversed the increased total LDL cholesterol observed in the OVX group. The findings underscore protective effects of E1 on the cardiovascular system, counteracting OVX-related oxidative stress and endothelial dysfunction in Wistar rats. E1 exhibits promising therapeutic benefits for managing cardiovascular health, particularly in postmenopausal conditions.

Gonadal status modulates large elastic artery stiffness in healthy middle-aged and older men

Hypogonadism is a risk factor for cardiovascular disease (CVD) in men related, in part, to increased oxidative stress. Elevated large artery stiffness and central pulsatile hemodynamics (e.g., pulse pressure and wave reflection magnitude) are independent risk factors for CVD. However, whether large artery stiffness and central pulsatile hemodynamics are (1) elevated in hypogonadal men independent of traditional CVD risk factors and (2) related to increased oxidative stress is unknown. Young men (N = 23; 30 ± 4 years) and middle-aged/older (MA/O) men with normal (> 400-1000 ng/dL; n = 57; 59 ± 7 years) or low testosterone (< 300 ng/dL; n = 21; 59 ± 7 years) underwent assessments of large artery stiffness (carotid ß-stiffness via ultrasonography) and central pulsatile hemodynamics (pulse wave analysis; SphygmoCor XCEL) following an infusion of saline or vitamin C to test the tonic suppression of vascular function by oxidative stress. Carotid stiffness differed by age (p < 0.001) and gonadal status within MA/O men (low testosterone vs. normal testosterone: 9.3 ± 0.7 vs. 8.0 ± 0.3U, p = 0.036). Central pulsatile hemodynamics did not differ by age or gonadal status (p > 0.119). Vitamin C did not alter carotid stiffness in any group (p > 0.171). There was a significant group × infusion interaction on aortic reflection magnitude (p = 0.015). Vitamin C treatment reduced aortic reflection magnitude in young and MA/O men with normal testosterone (both p < 0.001) but not MA/O men with low testosterone (p = 0.891). Collectively, hypogonadism may accelerate age-related large artery stiffening in MA/O men with low testosterone, independent of CVD risk factors; however, this is not related to increased reactive oxygen species sensitive to an acute vitamin C infusion.

Precision Nutrition for Management of Cardiovascular Disease Risk during Menopause

BACKGROUND

Women can spend up to 40% of their lives in the postmenopausal state. As women begin to transition into menopause, known as perimenopause, changes in hormonal concentrations and body composition dramatically increase overall cardiometabolic risk. Dietary patterns and interventions can be utilized to prevent and treat cardiovascular disease (CVD) and some dietary patterns over others may be more beneficial due to their specific effects on the health aspects of menopause. In this narrative review, we summarize key cardiovascular alterations that occur during the menopause transition and explore current dietary recommendations to address CVD risk as well as explore the new frontier of precision nutrition and the implications for nutrition prescription during menopause.

SUMMARY

Popular dietary interventions for CVD such as the Dietary Approaches to Stop Hypertension (DASH) diet and the Mediterranean diet (MED) have limited data in women following menopause. However, both diets improve CVD risk biomarkers of total cholesterol and low-density lipoprotein cholesterol as well as lower oxidative stress and inflammation and improve endothelial function. As the menopause transition increases the risk for developing metabolic syndrome, insulin insensitivity, and dyslipidemia, the DASH diet and MED may be impactful dietary strategies for mediating CVD risk in menopausal women. However, these are "one-size-fits-all" approaches that neglect individual characteristics such as genetic predisposition and environmental factors. Precision nutrition considers individual factors for nutrition prescription, spanning from evaluating food intake preferences and behaviors to deep phenotyping. Data from a large-scale investigation of the menopause transition suggests nutritional strategies that address postprandial glycemic responses, and the gut microbiome may attenuate some of the unfavorable effects of menopause on CVD risk factors.

KEY MESSAGES

Considering menopause, women are a clinical population that would greatly benefit from precision nutrition. Future research should explore the use of machine learning and artificial intelligence in a precision nutrition framework to modify the DASH diet and MED to address adverse effects that occur during the menopause transition are vital for supporting women's health as they age.

Effectiveness of exercise training on arterial stiffness and blood pressure among postmenopausal women: a systematic review and meta-analysis

BACKGROUND

The acute and long-term benefits of exercise training on cardiovascular health have been well established. The systematic review and meta-analysis aimed to systematically assess the effectiveness of exercise training on arterial stiffness and blood pressure among postmenopausal women with elevated blood pressure.

METHODS

A comprehensive search was conducted on PubMed, Embase, Web of Science, ProQuest, Cochrane Library, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov website from inception to September 30, 2023, to identify the randomized controlled trials (RCTs), which evaluated the effectiveness of exercise training on arterial stiffness and blood pressure in postmenopausal women. Standardized mean differences (SMD), weighted mean differences (WMD), and 95% confidence intervals (95% CIs) were calculated using random/fixed effects models. Quality assessment was performed using the modified Jadad scale and the Cochrane Risk of Bias Tool. Sensitivity analysis and subgroup analysis were conducted based on drug dosage, treatment duration, and age of administration to further explore potential heterogeneity. Funnel plots were performed to assess publication bias and Begg's regression test was carried out for funnel plot asymmetry.

RESULTS

Twenty-two RCTs involving 1978 participants were included in the quantitative analysis. The mean quality of eligible studies was 4.2 out of 7 based on the modified Jadad scale. The results indicated that exercise training had a significant effect on reducing brachial-ankle pulse wave velocity [MD = - 0.69, 95%CI (- 1.11, - 0.27), P = 0.001], decreasing augmentation index (AIx) [MD = - 6.00, 95%CI (- 6.39, - 5.61), P < 0.00001] and AIx normalized to a heart rate of 75 beats per minute (AIx@75%) [MD = - 7.01, 95%CI - 7.91 to - 6.12, P < 0.00001], lowering systolic blood pressure [MD = - 6.19, 95%CI - 9.24 to - 3.15, P < 0.0001], diastolic blood pressure [MD = - 3.57, 95%CI (- 6.10, - 1.03), P = 0.006) and pulse pressure [MD = - 8.52, 95%CI (- 16.27, - 0.76), P = 0.03]. Subgroup analysis revealed that baseline blood pressure levels had a large impact on the effect of exercise training.

CONCLUSIONS

The systematic review and meta-analysis suggested that exercise training may ameliorate arterial stiffness and reduce blood pressure in postmenopausal women with elevated blood pressure. However, the optimal mode of exercise training that improves arterial stiffness and blood pressure in this population requires further investigation.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021211268.

L-Citrulline Supplementation Improves Arterial Blood Flow and Muscle Oxygenation during Handgrip Exercise in Hypertensive Postmenopausal Women

Endothelial dysfunction decreases exercise limb blood flow (BF) and muscle oxygenation. Acute L-Citrulline supplementation (CIT) improves muscle tissue oxygen saturation index (TSI) and deoxygenated hemoglobin (HHb) during exercise. Although CIT improves endothelial function (flow-mediated dilation [FMD]) in hypertensive women, the impact of CIT on exercise BF and muscle oxygenation (TSI) and extraction (HHb) are unknown. We examined the effects of CIT (10 g/day) and a placebo for 4 weeks on blood pressure (BP), arterial vasodilation (FMD, BF, and vascular conductance [VC]), and forearm muscle oxygenation (TSI and HHb) at rest and during exercise in 22 hypertensive postmenopausal women. Compared to the placebo, CIT significantly (p < 0.05) increased FMD (Δ-0.7 ± 0.6% vs. Δ1.6 ± 0.7%) and reduced aortic systolic BP (Δ3 ± 5 vs. Δ-4 ± 6 mmHg) at rest and improved exercise BF (Δ17 ± 12 vs. Δ48 ± 16 mL/min), VC (Δ-21 ± 9 vs. Δ41 ± 14 mL/mmHg/min), TSI (Δ-0.84 ± 0.58% vs. Δ1.61 ± 0.46%), and HHb (Δ1.03 ± 0.69 vs. Δ-2.76 ± 0.77 μM). Exercise BF and VC were positively correlated with improved FMD and TSI during exercise (all p < 0.05). CIT improved exercise artery vasodilation and muscle oxygenation via increased endothelial function in hypertensive postmenopausal women.

Seven-day dietary nitrate supplementation clinically significantly improves basal macrovascular function in postmenopausal women: a randomized, placebo-controlled, double-blind, crossover clinical trial

Introduction

Cardiovascular disease (CVD) is the leading cause of death in women, with increased risk following menopause. Dietary intake of beetroot juice and other plant-based nitrate-rich foods is a promising non-pharmacological strategy for increasing systemic nitric oxide and improving endothelial function in elderly populations. The purpose of this randomized, placebo-controlled, double-blind, crossover clinical trial was to determine the effects of short-term dietary nitrate (NO3 -) supplementation, in the form of beetroot juice, on resting macrovascular endothelial function and endothelial resistance to whole-arm ischemia-reperfusion (IR) injury in postmenopausal women at two distinct stages of menopause.

Methods

Early-postmenopausal [1-6 years following their final menstrual period (FMP), n = 12] and late-postmenopausal (6+ years FMP, n = 12) women consumed nitrate-rich (400 mg NO3 -/70 mL) and nitrate-depleted beetroot juice (approximately 40 mg NO3 -/70 mL, placebo) daily for 7 days. Brachial artery flow-mediated dilation (FMD) was measured pre-supplementation (Day 0), and approximately 24 h after the last beetroot juice (BR) dose (Day 8, post-7-day BR). Consequently, FMD was measured immediately post-IR injury and 15 min later (recovery).

Results

Results of the linear mixed-effects model revealed a significantly greater increase in resting FMD with 7 days of BRnitrate compared to BRplacebo (mean difference of 2.21, 95% CI [0.082, 4.34], p = 0.042); however, neither treatment blunted the decline in post-IR injury FMD in either postmenopausal group. Our results suggest that 7-day BRnitrate-mediated endothelial protection is lost within the 24-h period following the final dose of BRnitrate.

Conclusion

Our findings demonstrate that nitrate-mediated postmenopausal endothelial protection is dependent on the timing of supplementation in relation to IR injury and chronobiological variations in dietary nitrate metabolism.

Clinical trial registration

https://classic.clinicaltrials.gov/ct2/show/NCT03644472.

Sex and sex steroids as determinants of cardiovascular risk

There are considerable sex differences regarding the risk of cardiovascular disease (CVD), including arterial hypertension, coronary artery disease (CAD) and stroke, as well as chronic renal disease. Women are largely protected from these conditions prior to menopause, and the risk increases following cessation of endogenous estrogen production or after surgical menopause. Cardiovascular diseases in women generally begin to occur at a later age than in men (on average with a delay of 10 years). Cessation of estrogen production also impacts metabolism, increasing the risk of developing obesity and diabetes. In middle-aged individuals, hypertension develops earlier and faster in women than in men, and smoking increases cardiovascular risk to a greater degree in women than it does in men. It is not only estrogen that affects female cardiovascular health and plays a protective role until menopause: other sex hormones such as progesterone and androgen hormones generate a complex balance that differentiates heart and blood vessel function in women compared to men. Estrogens improve vasodilation of epicardial coronary arteries and the coronary microvasculature by augmenting the release of vasodilating factors such as nitric oxide and prostacyclin, which are mechanisms of coronary vasodilatation that are more pronounced in women compared to men. Estrogens are also powerful inhibitors of inflammation, which in part explains their protective effects on CVD and chronic renal disease. Emerging evidence suggests that sex chromosomes also play a significant role in shaping cardiovascular risk. The cardiovascular protection conferred by endogenous estrogens may be extended by hormone therapy, especially using bioidentical hormones and starting treatment early after menopause.

Accelerated Aging Induced by an Unhealthy High-Fat Diet: Initial Evidence for the Role of Nrf2 Deficiency and Impaired Stress Resilience in Cellular Senescence

High-fat diets (HFDs) have pervaded modern dietary habits, characterized by their excessive saturated fat content and low nutritional value. Epidemiological studies have compellingly linked HFD consumption to obesity and the development of type 2 diabetes mellitus. Moreover, the synergistic interplay of HFD, obesity, and diabetes expedites the aging process and prematurely fosters age-related diseases. However, the underlying mechanisms driving these associations remain enigmatic. One of the most conspicuous hallmarks of aging is the accumulation of highly inflammatory senescent cells, with mounting evidence implicating increased cellular senescence in the pathogenesis of age-related diseases. Our hypothesis posits that HFD consumption amplifies senescence burden across multiple organs. To scrutinize this hypothesis, we subjected mice to a 6-month HFD regimen, assessing senescence biomarker expression in the liver, white adipose tissue, and the brain. Aging is intrinsically linked to impaired cellular stress resilience, driven by dysfunction in Nrf2-mediated cytoprotective pathways that safeguard cells against oxidative stress-induced senescence. To ascertain whether Nrf2-mediated pathways shield against senescence induction in response to HFD consumption, we explored senescence burden in a novel model of aging: Nrf2-deficient (Nrf2+/-) mice, emulating the aging phenotype. Our initial findings unveiled significant Nrf2 dysfunction in Nrf2+/- mice, mirroring aging-related alterations. HFD led to substantial obesity, hyperglycemia, and impaired insulin sensitivity in both Nrf2+/- and Nrf2+/+ mice. In control mice, HFD primarily heightened senescence burden in white adipose tissue, evidenced by increased Cdkn2a senescence biomarker expression. In Nrf2+/- mice, HFD elicited a significant surge in senescence burden across the liver, white adipose tissue, and the brain. We postulate that HFD-induced augmentation of senescence burden may be a pivotal contributor to accelerated organismal aging and the premature onset of age-related diseases.

Effects of regular exercise on vascular function with aging: Does sex matter?

Vascular aging, featuring endothelial dysfunction and large elastic artery stiffening, is a major risk factor for the development of age-associated cardiovascular diseases (CVDs). Vascular aging is largely mediated by an excessive production of reactive oxygen species (ROS) and increased inflammation leading to reduced bioavailability of the vasodilatory molecule nitric oxide and remodeling of the arterial wall. Other cellular mechanisms (i.e., mitochondrial dysfunction, impaired stress response, deregulated nutrient sensing, cellular senescence), termed "hallmarks" or "pillars" of aging, may also contribute to vascular aging. Gonadal aging, which largely impacts women but also impacts some men, modulates the vascular aging process. Regular physical activity, including both aerobic and resistance exercise, is a first-line strategy for reducing CVD risk with aging. Although exercise is an effective intervention to counter vascular aging, there is considerable variation in the vascular response to exercise training with aging. Aerobic exercise improves large elastic artery stiffening in both middle-aged/older men and women and enhances endothelial function in middle-aged/older men by reducing oxidative stress and inflammation and preserving nitric oxide bioavailability; however, similar aerobic exercise training improvements are not consistently observed in estrogen-deficient postmenopausal women. Sex differences in adaptations to exercise may be related to gonadal aging and declines in estrogen in women that influence cellular-molecular mechanisms, disconnecting favorable signaling in the vasculature induced by exercise training. The present review will summarize the current state of knowledge on vascular adaptations to regular aerobic and resistance exercise with aging, the underlying mechanisms involved, and the moderating role of biological sex.

Dietary Nitrate from Plant Foods: A Conditionally Essential Nutrient for Cardiovascular Health

Under specific conditions, such as catabolic stress or systemic inflammation, endogenous nutrient production becomes insufficient and exogenous supplementation (for example, through dietary intake) is required. Herein, we propose consideration of a dietary nitrate from plant foods as a conditionally essential nutrient for cardiovascular health based on its role in nitric oxide homeostasis. Nitrate derived from plant foods may function as a conditionally essential nutrient, whereas nitrate obtained from other dietary sources, such as drinking water and cured/processed meats, warrants separate consideration because of the associated health risks. We have surveyed the literature and summarized epidemiological evidence regarding the effect of dietary nitrate on cardiovascular disease and risk factors. Meta-analyses and population-based observational studies have consistently demonstrated an inverse association of dietary nitrate with blood pressure and cardiovascular disease outcomes. Considering the available evidence, we suggest 2 different approaches to providing dietary guidance on nitrate from plant-based dietary sources as a nutrient: the Dietary Reference Intakes developed by the National Academies of Sciences, Engineering, and Medicine, and the dietary guidelines evaluated by the Academy of Nutrition and Dietetics. Ultimately, this proposal underscores the need for food-based dietary guidelines to capture the complex and context-dependent relationships between nutrients, particularly dietary nitrate, and health.

Improving Cognitive Function with Nutritional Supplements in Aging: A Comprehensive Narrative Review of Clinical Studies Investigating the Effects of Vitamins, Minerals, Antioxidants, and Other Dietary Supplements

Cognitive impairment and dementia are burgeoning public health concerns, especially given the increasing longevity of the global population. These conditions not only affect the quality of life of individuals and their families, but also pose significant economic burdens on healthcare systems. In this context, our comprehensive narrative review critically examines the role of nutritional supplements in mitigating cognitive decline. Amidst growing interest in non-pharmacological interventions for cognitive enhancement, this review delves into the efficacy of vitamins, minerals, antioxidants, and other dietary supplements. Through a systematic evaluation of randomized controlled trials, observational studies, and meta-analysis, this review focuses on outcomes such as memory enhancement, attention improvement, executive function support, and neuroprotection. The findings suggest a complex interplay between nutritional supplementation and cognitive health, with some supplements showing promising results and others displaying limited or context-dependent effectiveness. The review highlights the importance of dosage, bioavailability, and individual differences in response to supplementation. Additionally, it addresses safety concerns and potential interactions with conventional treatments. By providing a clear overview of current scientific knowledge, this review aims to guide healthcare professionals and researchers in making informed decisions about the use of nutritional supplements for cognitive health.

Effect of menstrual status on lipid profile: A cross-sectional study in a tertiary care hospital in Nepal

Background: The ovarian follicular cell's degradation and subsequent decrease in the synthesis of estrogen results in the decreased cardiovascular protection. As a result, the incidence of cardiovascular disease (CVD) increases in postmenopausal women and is characterized by change in lipid profile. This study sought to ascertain the extent of the impact that menstrual status might have on lipid profiles among premenopausal and postmenopausal women. Methods: A cross-sectional study was conducted with 260 premenopausal and postmenopausal women (1: 1) and serum lipid component concentrations (high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TGs), and total cholesterol (TC)) were measured. A comparison between two groups was made between premenopausal and postmenopausal women, and regression was carried out to estimate the effect of menstrual status on lipid components. Results: Compared with premenopausal women, the concentrations of the lipid components (HDL-C, LDL-C, TG, and TC) were found to be significantly higher in postmenopausal women. Using the linear regression, menstruation status was able to predict 11.7%-13.3% of the lipid components (TG and TC) when age and weight were adjusted. Conclusion: The difference in lipid components between premenopausal women and postmenopausal women exists, with menstrual status explaining 11.7%-13.3% variance for the observed lipid level. The factors influencing the lipid profile beside the menstrual status should also be explored. External intervention such as estrogen replacement therapy is also recommended in case of deviation of lipid profile from the suggested normal clinical range.

Menstrual cycle hormones and oral contraceptives: a multimethod systems physiology-based review of their impact on key aspects of female physiology

Hormonal changes around ovulation divide the menstrual cycle (MC) into the follicular and luteal phases. In addition, oral contraceptives (OCs) have active (higher hormone) and placebo phases. Although there are some MC-based effects on various physiological outcomes, we found these differences relatively subtle and difficult to attribute to specific hormones, as estrogen and progesterone fluctuate rather than operating in a complete on/off pattern as observed in cellular or preclinical models often used to substantiate human data. A broad review reveals that the differences between the follicular and luteal phases and between OC active and placebo phases are not associated with marked differences in exercise performance and appear unlikely to influence muscular hypertrophy in response to resistance exercise training. A systematic review and meta-analysis of substrate oxidation between MC phases revealed no difference between phases in the relative carbohydrate and fat oxidation at rest and during acute aerobic exercise. Vascular differences between MC phases are also relatively small or nonexistent. Although OCs can vary in composition and androgenicity, we acknowledge that much more work remains to be done in this area; however, based on what little evidence is currently available, we do not find compelling support for the notion that OC use significantly influences exercise performance, substrate oxidation, or hypertrophy. It is important to note that the study of females requires better methodological control in many areas. Previous studies lacking such rigor have contributed to premature or incorrect conclusions regarding the effects of the MC and systemic hormones on outcomes. While we acknowledge that the evidence in certain research areas is limited, the consensus view is that the impact of the MC and OC use on various aspects of physiology is small or nonexistent.

Protective effects of blueberries on vascular function: A narrative review of preclinical and clinical evidence

Blueberries are rich in nutrients and (poly)phenols, popular with consumers, and a major agricultural crop with year-round availability supporting their use in food-based strategies to promote human health. Accumulating evidence indicates blueberry consumption has protective effects on cardiovascular health including vascular dysfunction (i.e., endothelial dysfunction and arterial stiffening). This narrative review synthesizes evidence on blueberries and vascular function and provides insight into underlying mechanisms with a focus on oxidative stress, inflammation, and gut microbiota. Evidence from animal studies supports beneficial impacts on vascular function. Human studies indicate acute and chronic blueberry consumption can improve endothelial function in healthy and at-risk populations and may modulate arterial stiffness, but that evidence is less certain. Results from cell, animal, and human studies suggest blueberry consumption improves vascular function through improving nitric oxide bioavailability, oxidative stress, and inflammation. Limited data in animals suggest the gut microbiome mediates beneficial effects of blueberries on vascular function; however, there is a paucity of studies evaluating the gut microbiome in humans. Translational evidence indicates anthocyanin metabolites mediate effects of blueberries on endothelial function, though this does not exclude potential synergistic and/or additive effects of other blueberry components. Further research is needed to establish the clinical efficacy of blueberries to improve vascular function in diverse human populations in a manner that provides mechanistic information. Translation of clinical research to the community/public should consider feasibility, social determinants of health, culture, community needs, assets, and desires, barriers, and drivers to consumption, among other factors to establish real-world impacts of blueberry consumption.

Assessment of the neuroprotective effect of Cocos nucifera L. oil on learning and behavior impairment in ovariectomized rats

Objective

The current study aimed to investigate whether Cocos nucifera L. oil (CO) is effective on menopause-related memory dysfunction in ovariectomized (OVX) rats.

Materials and Methods

Fifty healthy female Wistar rats were randomly selected and classified into five groups as control, OVX rats, and three OVX groups of rats which received three different doses (100, 200, and 400 mg/kg/day) of CO for five consecutive weeks by gavage. To assess the effect of CO, neurobehavioral tests such as Morris water maze (MWM) and Passive avoidance (PA) were done and then the animals were sacrificed to remove cortical and hippocampal tissues for biochemical analysis.

Results

In both behavioral tests including MWM and PA, treatment with CO particularly two higher doses of 200, and 400 mg/kg demonstrated significant improvement in comparison with OVX group. Furthermore, antioxidant biomarkers such as total thiol content, catalase and superoxide dismutase (SOD) activities were significantly higher in the OVX-CO groups versus the OVX group. On the contrary, malondialdehyde (MDA) concentration as an oxidative stress biomarker was remarkably lower in the OVX-CO200 and 400 mg groups than the OVX group.

Conclusion

The present study demonstrated the significant improvement of CO on learning and memory impairment induced by ovariectomy. Although the exact mechanism needs further investigation, it might have occurred due to the anti-oxidative effect of CO.

Older females but not males exhibit increases in cerebral blood velocity, despite similar pulsatility increases after high-intensity resistance exercise

Sex differences in resting cerebral hemodynamics decline with aging. Given that acute resistance exercise (RE) is a hypertensive challenge, it may reveal sex-dependent abnormalities in cerebral hemodynamics. Thus, we hypothesized that cerebral blood velocity and pulsatility responses to RE would be sex-dependent in older adults. Fourteen older females and 11 males (50-68 yr) completed a high-intensity unilateral isokinetic knee flexion/extension exercise. Measurements were collected at baseline, immediately, 5- and 30-min post-RE. Blood pressure was measured via finger photoplethysmography. Mean middle cerebral artery blood velocity (MCAv) and pulsatility were assessed via transcranial Doppler ultrasound. Carotid pulsatility was obtained via duplex ultrasound. MCAv increased immediately after RE in older females [mean difference (d) = 6.02, 95% CI: 1.66 to 10.39 cm/s, P < 0.001] but not in males (d = -0.72, 95% CI: -3.83 to 5.27 cm/s, P = 0.99), followed by similar reductions 5-min post-RE in older females (d = -4.40, 95% CI: -8.81 to -0.10 cm/s, P = 0.045) and males (d = -6.41, 95% CI: -11.19 to -1.62 cm/s, P = 0.003). MCAv pulsatility increased similarly in older females (d = 0.24, 95% CI: 0.11 to 0.40, P < 0.001) and males (d = 0.38, 95% CI: 0.20 to 0.53, P < 0.001), persisting 5-min post-RE. Older females showed smaller increases in carotid pulsatility immediately after RE (d = 0.18, 95% CI: 0.03 to 0.38, P = 0.01) than males (d = 0.48, 95% CI: 0.26 to 0.68, P < 0.001). An exercise-mediated hypertensive stimulus revealed differential sex responses in MCAv and carotid pulsatility but not in cerebral pulsatility. Cerebral pulsatility findings suggest a similar sex susceptibility to cerebrovascular abnormalities following exercise-mediated hypertensive stimulus in older adults.NEW & NOTEWORTHY Sex differences in resting cerebral hemodynamics decline with advancing age as females experience larger reductions in cerebral blood velocity and steeper pulsatility increases than males. However, an exercise-mediated hypertensive stimulus might reveal sex differences in cerebral hemodynamics not apparent at rest. Following high-intensity resistance exercise, older females but not males exhibit increases in cerebral blood velocity, despite similar increases in cerebral pulsatility. The susceptibility to cerebrovascular abnormalities following exercise-mediated hypertensive stimulus appears similar between sexes.

Menopausal stage differences in endothelial resistance to ischemia-reperfusion injury

BACKGROUND

In postmenopausal women, reduced ovarian function precedes endothelial dysfunction and attenuated endothelial resistance to ischemia-reperfusion (IR) injury. We hypothesized that IR injury would lower endothelial function, with premenopausal women demonstrating the greatest protection from injury, followed by early, then late postmenopausal women.

METHODS

Flow-mediated dilation (FMD) was assessed at baseline and following IR injury in premenopausal (n = 11), early (n = 11; 4 ± 1.6 years since menopause), and late (n = 11; 15 ± 5.5 years since menopause) postmenopausal women.

RESULTS

There were significant group differences in baseline FMD (p = 0.007); post hoc analysis revealed a similar resting FMD between premenopausal (7.8% ± 2.1%) and early postmenopausal (7.1% ± 2.7%), but significantly lower FMD in late postmenopausal women (4.5% ± 2.3%). Results showed an overall decline in FMD after IR injury (p < 0.001), and a significant condition*time interaction (p = 0.048), with early postmenopausal women demonstrating the most significant decline in FMD following IR.

CONCLUSION

Our findings indicate that endothelial resistance to IR injury is attenuated in healthy early postmenopausal women.

The Protective Effect of Exogenous 17β-Estradiol against Experimentally Induced Oxidative Damage to Membrane Lipids Is Stronger in Male vs. Female Porcine Thyroids: Preliminary Results

It is well-known that thyroid diseases are more prevalent in women than in men. The contribution of sex hormones may explain such disparity. The aim of this study was to check if there are any differences between sexes concerning the effects of 17β-estradiol on oxidative damage to membrane lipids (lipid peroxidation) in porcine thyroid homogenates under basal conditions and in the presence of Fenton reaction (Fe2+ + H2O2→Fe3+ + •OH + OH-) substrates. We observed that 17β-estradiol did not change the basal level of lipid peroxidation (measured spectrophotometrically as concentrations of malondialdehyde + 4-hydroxyalkenals) in thyroid homogenates, and no differences were found between sexes. The lipid peroxidation level in response to Fe2+ + H2O2 plus 17β-estradiol was lower in male thyroids. In turn, in male thyroids, 17β-estradiol reduced experimentally induced lipid peroxidation in as low of a concentration as 0.1 μM, whereas in female thyroids the lowest effective concentration of 17β-estradiol was 10 μM, i.e., 100 times higher than in males. In conclusion, the protective effects of exogenous 17β-estradiol against experimentally induced oxidative damage to membrane lipids is stronger in male than in female thyroids. Our observation suggests that female tissue is less sensitive to the protective effects of exogenous 17β-estradiol. This sexual dimorphism of oxidative processes in the thyroid may constitute one of the mechanisms of the different prevalence of thyroid diseases in women and in men.

Estrogen and the Vascular Endothelium: The Unanswered Questions

Premenopausal women have a lower incidence of cardiovascular disease (CVD) compared with their age-matched male counterparts; however, this discrepancy is abolished following the transition to menopause or during low estrogen states. This, combined with a large amount of basic and preclinical data indicating that estrogen is vasculoprotective, supports the concept that hormone therapy could improve cardiovascular health. However, clinical outcomes in individuals undergoing estrogen treatment have been highly variable, challenging the current paradigm regarding the role of estrogen in the fight against heart disease. Increased risk for CVD correlates with long-term oral contraceptive use, hormone replacement therapy in older, postmenopausal cisgender females, and gender affirmation treatment for transgender females. Vascular endothelial dysfunction serves as a nidus for the development of many cardiovascular diseases and is highly predictive of future CVD risk. Despite preclinical studies indicating that estrogen promotes a quiescent, functional endothelium, it still remains unclear why these observations do not translate to improved CVD outcomes. The goal of this review is to explore our current understanding of the effect of estrogen on the vasculature, with a focus on endothelial health. Following a discussion regarding the influence of estrogen on large and small artery function, critical knowledge gaps are identified. Finally, novel mechanisms and hypotheses are presented that may explain the lack of cardiovascular benefit in unique patient populations.

Daily blueberry consumption for 12 weeks improves endothelial function in postmenopausal women with above-normal blood pressure through reductions in oxidative stress: a randomized controlled trial

Estrogen-deficient postmenopausal women have oxidative stress-mediated suppression of endothelial function that is exacerbated by high blood pressure. Previous research suggests blueberries may improve endothelial function through reductions in oxidative stress, while also exerting other cardiovascular benefits. The objective of this study was to examine the efficacy of blueberries to improve endothelial function and blood pressure in postmenopausal women with above-normal blood pressure, and to identify potential mechanisms for improvements in endothelial function. A randomized, double-blind, placebo-controlled, parallel-arm clinical trial was performed, where postmenopausal women aged 45-65 years with elevated blood pressure or stage 1-hypertension (total n = 43, endothelial function n = 32) consumed 22 g day^-1 of freeze-dried highbush blueberry powder or placebo powder for 12 weeks. Endothelial function was assessed at baseline and 12 weeks through ultrasound measurement of brachial artery flow-mediated dilation (FMD) normalized to shear rate area under the curve (FMD/SR_AUC) before and after intravenous infusion of a supraphysiologic dose of ascorbic acid to evaluate whether FMD improvements were mediated by reduced oxidative stress. Hemodynamics, arterial stiffness, cardiometabolic blood biomarkers, and plasma (poly)phenol metabolites were assessed at baseline and 4, 8, and 12 weeks, and venous endothelial cell protein expression was assessed at baseline and 12 weeks. Absolute FMD/SR_AUC was 96% higher following blueberry consumption compared to baseline (p < 0.05) but unchanged in the placebo group (p > 0.05), and changes from baseline to 12 weeks were greater in the blueberry group than placebo (+1.09 × 10^-4 ± 4.12 × 10^-5vs. +3.82 × 10^-6 ± 1.59 × 10^-5, p < 0.03, respectively). The FMD/SR_AUC response to ascorbic acid infusion was lower (p < 0.05) at 12 weeks compared to baseline in the blueberry group with no change in the placebo group (p > 0.05). The sum of plasma (poly)phenol metabolites increased at 4, 8, and 12 weeks in the blueberry group compared to baseline, and were higher than the placebo group (all p < 0.05). Increases in several plasma flavonoid and microbial metabolites were also noted. No major differences were found for blood pressure, arterial stiffness, blood biomarkers, or endothelial cell protein expression following blueberry consumption. These findings suggest daily consumption of freeze-dried blueberry powder for 12 weeks improves endothelial function through reduced oxidative stress in postmenopausal women with above-normal blood pressure. The clinical trial registry number is NCT03370991 (https://clinicaltrials.gov).

Comparison of peripheral and cerebral vascular function between premenopausal, early and late postmenopausal females

NEW FINDINGS

What is the central question of this study? We sought to investigate whether peripheral and cerebrovascular function are impaired in early and late postmenopausal females compared with premenopausal females, while also accounting for nitric oxide and estradiol levels. What is the main finding and its importance? We observed no differences in peripheral vascular and cerebrovascular function between healthy and physically active premenopausal females and early and late postmenopausal females. Our findings contradict previous cross-sectional observations of vascular and cerebrovascular dysfunction across menopause. Longitudinal studies assessing vascular and cerebrovascular outcomes across the menopausal transition are warranted.

ABSTRACT

The risk of cardiovascular and cerebrovascular disease increases in ageing females, coinciding with the onset of menopause. Differences in peripheral and cerebrovascular function across menopausal stages, however, are poorly characterized. The aim of this study was to compare peripheral and cerebrovascular function between healthy premenopausal (PRE), early (1-6 years after final menstrual period; E-POST) and late (>6 years after final menstrual period; L-POST) postmenopausal females. We also explored the association between reproductive hormones, NO bioavailability and cerebrovascular function. In 39 females (40-65 years of age), we measured arterial stiffness, brachial artery flow-mediated dilatation, and cerebrovascular reactivity (CVR) to hypercapnia in the middle (MCAv) and internal (ICA) carotid arteries. Follicle-stimulating hormone, estradiol, progesterone and plasma nitrate and nitrite concentrations were also measured. Years since final menstrual period (PRE, 0 ± 0 years; E-POST, 3 ± 1 years; L-POST, 11 ± 4 years; P < 0.001) and estradiol levels (PRE, 145.5 ± 65.6 pg ml-1 ; E-POSTm 30.2 ± 81.2 pg ml-1 ; L-POST, 7.7 ± 11.3 pg ml-1 ; P < 0.001) were different between groups. All groups exceeded the guidelines for recommended physical activity. There were no group differences in blood pressure (P = 0.382), arterial stiffness (P = 0.129), flow-mediated dilatation (P = 0.696) or MCAv CVR (P = 0.442). The ICA CVR blood flow response was lower in PRE compared with L-POST (26.5 ± 19.2 vs. 47.8 ± 12.6%; P = 0.010), but after adjusting for age these differences were no longer present. Flow-mediated dilatation (r = 0.313, P = 0.105) and ICA CVR (r = -0.154, P = 0.495) were not associated with the estradiol concentration. There were no associations between the estradiol concentration and NO bioavailability. These results suggest that in healthy, physically active early and late postmenopausal females, vascular and cerebrovascular function is generally well preserved.

Cardiovascular profiles associated with white matter hyperintensities in healthy young women

Women who experience hypertension in pregnancy have increased risk of both chronic hypertension and dementia. High blood pressure is associated with increased evidence of white matter hyperintensities (WMH) in brain imaging. WMH are disruptions of the white matter of the brain that occur with demyelination and axonal degeneration, are associated with vascular disease, occur more frequently in people with hypertension, and are associated with cognitive impairment. We evaluated the relationship between WMH and subclinical cardiovascular function in healthy young nulliparous women and women with a history of early-onset preeclampsia. Sixty-two reproductive-aged women were assessed during the follicular phase of the menstrual cycle after a 3-day sodium/potassium-controlled diet. Half of participants had a history of early-onset preeclampsia, and half were nulliparous. Blood was drawn to assess inflammatory markers. Cardiovascular assessments included tonometric blood pressure monitoring, volume loading to assess vascular compliance, echocardiography to assess cardiac ejection time, brachial pulse wave velocity of the brachial artery, assessing cardiovascular stiffness, and brachial artery flow mediated vasodilation to assess endothelial mediated dilatory response. T2 fluid-attenuated inversion recovery (FLAIR) MRI imaging was obtained. Two raters, blinded to cardiovascular assessments and pregnancy history, reviewed MRI scans for evidence of WMH using the Fazekas rating scale. WMHs were detected in 17 women; 45 had normal white matter structure. Participants with Fazekas score>0 had exaggerated response to volume loading compared to women with a Fazekas score of 0 and longer cardiac ejection times. Fazekas scores >0 had lower brachial flow-mediated vasodilation and increased white blood count compared to those with no evidence of WMH. Women with WMH had reduced cardiovascular compliance, and a trend towards decreased endothelial responsiveness compared to those without WMH. These data demonstrated that the relationship between cardiovascular and brain health was detectable in young, healthy, reproductive-aged women, and may play a role in later development of clinical disease. These findings may help identify women who are at risk for cognitive decline and pathological aging.

Sex differences in microvascular function and arterial hemodynamics in nondialysis chronic kidney disease

Cardiovascular disease (CVD) is the leading cause of death in chronic kidney disease (CKD). Abnormal arterial hemodynamics contribute to CVD, a relationship that can be mediated by microvascular dysfunction. The purpose of this study was to investigate potential sex differences in arterial hemodynamics and microvascular dysfunction in patients with stages 3 to 4 CKD. Vascular function was assessed in 22 male (mean ± SD; age, 56 ± 13 yr) and 10 female (age, 63 ± 9 yr) patients. Arterial hemodynamics were acquired with combined tonometry and oscillometry. Skin blood flow was used as a model of microvascular function. Participants were instrumented with three microdialysis fibers for the delivery of 1) Ringer's solution; 2) superoxide dismutase mimetic, Tempol; and 3) nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor, apocynin. Blood flow was measured via laser-Doppler flowmetry during standardized local heating (42°C). Central pulse pressure (mean ± SE; 62 ± 9 vs. 46 ± 3 mmHg; P = 0.01) and augmentation index (36 ± 3 vs. 26 ± 3%; P = 0.03) were higher in females. There was a trend for higher central systolic pressures in females (146 ± 9 vs. 131 ± 3 mmHg; P = 0.06). Females reported higher forward (39 ± 4 vs. 29 ± 2 mmHg; P = 0.004) and reflected (27 ± 3 vs. 19 ± 1 mmHg; P < 0.001) wave amplitudes. Cutaneous vascular function was impaired in females compared with males (77 ± 3 vs. 89 ± 1%, P = 0.001). Microvascular function was improved following the delivery of Tempol and apocynin in females but not in males. Female patients with CKD had poorer central hemodynamics and reduced microvascular function compared with their male counterparts. Oxidative stress may contribute to lower microvascular function observed in females.NEW & NOTEWORTHY There are limited data regarding the physiological mechanisms of potential sex differences in central hemodynamics and vascular function in chronic kidney disease (CKD). We report that older female patients with nondialysis CKD have higher central pulse pressures compared with male patients with CKD. In addition, older females with CKD have lower microvascular function compared with their male counterparts, and oxidative stress contributes to the lower microvascular function in older female patients with CKD.

Role of BH4 deficiency as a mediator of oxidative stress-related endothelial dysfunction in menopausal women

Endothelial function (brachial artery flow-mediated dilation [FMD]) is reduced in estrogen-deficient postmenopausal women, mediated, in part, by reduced nitric oxide (NO) bioavailability, secondary to tetrahydrobiopterin (BH4) deficiency and oxidative stress. FMD is increased, but not fully restored, in postmenopausal women after acute intravenous vitamin C (VITC; superoxide scavenger) or oral BH4 supplementation. In vitro studies demonstrate that coadministration of VITC with BH4 prevents endothelial nitric oxide synthase (eNOS) uncoupling and reductions in NO by peroxynitrite. To investigate mechanisms of endothelial dysfunction in women, we assessed the separate and combined effects of VITC and BH4 to determine whether coadministration of VITC + BH4 improves FMD in healthy postmenopausal women (n = 19, 58 ± 5 yr) to premenopausal (n = 14, 36 ± 9 yr) levels, with exploratory testing in perimenopausal women (n = 8, 51 ± 3 yr). FMD was measured during acute intravenous infusions of saline (control) and VITC (∼2-3 g) ∼3 h after a single dose of oral BH4 (KUVAN, 10 mg/kg body wt) or placebo (randomized crossover, separated by ∼1 mo). Under the placebo condition, FMD was reduced in postmenopausal compared with premenopausal women during the saline infusion (5.6 ± 0.7 vs. 11.6 ± 0.9%, P < 0.001) and increased in postmenopausal women during VITC (+3.5 [1.4, 5.6]%, P = 0.001) and acute BH4 (+1.8 [0.37, 3.2]%, P = 0.01) alone. Coadministration of VITC + BH4 increased FMD in postmenopausal women (+3.0 [1.7, 4.3]%, P < 0.001), but FMD remained reduced compared with premenopausal women (P = 0.02). Exploratory analyses revealed that VITC + BH4 did not restore FMD in perimenopausal women to premenopausal levels (P = 0.045). Coadministration of VITC + BH4 does not restore FMD in menopausal women, suggesting that additional mechanisms may be involved.NEW & NOTEWORTHY Endothelial function is reduced across the menopausal stages related to increased oxidative stress associated with estrogen deficiency. In vitro studies demonstrate that coadministration of VITC with BH4 prevents endothelial nitric oxide synthase (eNOS) uncoupling and reductions in NO by peroxynitrite; however, this remains untested in humans. We demonstrate that the coadministration of BH4 + VITC does not restore endothelial function in perimenopausal and postmenopausal women to the level of premenopausal women, suggesting that other mechanisms contribute.

Evaluation of atherosclerosis-related biomarkers during perimenopause: A prospective cohort study in women with endometriosis

AIM

Endometriosis is linked to asymptomatic atherosclerosis and increases the risk of cardiovascular disease (CVD). Vascular function tests are used to assess atherosclerosis, an important indicator of CVD development. In this study, we aimed to evaluate atherosclerosis-related biomarkers, such as vascular function tests and laboratory data, in perimenopausal women with endometriosis.

METHODS

This prospective cohort study enrolled 207 women (≥40 years old) with endometriosis. Laboratory data, ankle brachial index (ABI), and cardio-ankle vascular index (CAVI) were evaluated.

RESULTS

The mean age, CAVI, and ABI of the participants at the initial examination were 45.02 years, 6.9 ± 0.6, and 1.07 ± 0.06, respectively. In multiple regression analysis, no factor was associated with CAVI, but ABI was significantly correlated with elevated total cholesterol (TC), low-density lipoprotein cholesterol, and estradiol (partial regression coefficient [β] = -0.00074, p = 0.017; β = -0.00075, p = 0.033; and β = -0.00022, p = 0.015, respectively). The annual rate of change in CAVI showed a positive correlation with TC and pentosidine and a negative correlation with history of hormone therapy. Neither correlation was strong. In a comparison of three groups classified by the annual rate of change in CAVI, the group with the severe change had a higher level of pentosidine. In adjusted multinomial logistic regression analysis, high pentosidine levels were a risk factor for increased rate of change in CAVI.

CONCLUSIONS

The association between CAVI and serum markers related to lipid metabolism and ovarian function was mild. Longitudinal analysis of CAVI showed an association with pentosidine, which may be helpful in assessing atherosclerosis risk in women with endometriosis during perimenopause.

Inspiratory muscle strength training for lowering blood pressure and improving endothelial function in postmenopausal women: comparison with “standard of care” aerobic exercise

Background: High blood pressure (BP), particularly systolic BP (SBP), is the major modifiable risk factor for cardiovascular diseases and related disorders of aging. SBP increases markedly with aging in women such that the prevalence of above-normal SBP (i.e., ≥120 mmHg) in postmenopausal women exceeds rates in age-matched men. This increase in SBP is associated with vascular endothelial dysfunction, mediated by excessive reactive oxygen species-induced oxidative stress and consequent reductions in nitric oxide bioavailability. Moderate-intensity aerobic exercise is a recommended lifestyle strategy for reducing SBP. However, adherence to aerobic exercise guidelines among postmenopausal women is low (<30%) and aerobic exercise does not consistently enhance endothelial function in estrogen-deficient postmenopausal women. High-resistance inspiratory muscle strength training (IMST) is a time-efficient, adherable lifestyle intervention that involves inhaling against resistance through a handheld device (30 breaths/day). Here, we present the protocol for a randomized controlled trial investigating the efficacy of 3 months of high-resistance IMST compared to guideline-based, “standard-of-care” aerobic exercise training for decreasing SBP and improving endothelial function in estrogen-deficient postmenopausal women with above-normal SBP (120–159 mmHg) at baseline (ClinicalTrials.gov Identifier: NCT05000515).

Methods: A randomized, single-blind, parallel-group design clinical trial will be conducted in 72 (36/group) estrogen-deficient postmenopausal women with above-normal SBP. Participants will complete baseline testing and then be randomized to either 3 months of high-resistance IMST (30 breaths/day, 6 days/week, 75% maximal inspiratory pressure) or moderate-intensity aerobic exercise training (brisk walking 25 min/day, 6 days/week, 40–60% heart rate reserve). Outcome measures will be assessed after 3 months of either intervention. Following end-intervention testing, participants will abstain from their assigned intervention for 6 weeks, after which BP and endothelial function will be assessed to evaluate the potential persistent effects of the intervention on the primary and secondary outcomes.

Discussion: This study is designed to compare the effectiveness of time-efficient, high-resistance IMST to guideline-based aerobic exercise training for lowering SBP and improving endothelial function, and interrogating potential mechanisms of action, in estrogen-deficient postmenopausal women.

Clinical Trial Registration:ClinicalTrials.gov, Identifier: NCT05000515.

A single dose of dietary nitrate supplementation protects against endothelial ischemia-reperfusion injury in early postmenopausal women

The onset of menopause and accompanying changes to ovarian hormones often precedes endothelial dysfunction in women. In particular, accelerated impairments in macrovascular and microvascular function coincide with the loss of estrogen, as does impaired endothelial responses to ischemia-reperfusion (IR) injury. In healthy, early postmenopausal women (n = 12; 3.9 ± 1.5 years since menopause) we tested the hypothesis that acute dietary nitrate (NO3-) supplementation would improve endothelial function and attenuate the magnitude of endothelial dysfunction following whole-arm IR in comparison with placebo. In this randomized, double-blind, placebo-controlled, crossover study we tested participants before and after NO3--rich (BRnitrate) and NO3--depleted (BRplacebo) beetroot juice (BR) consumption, as well as following IR injury, and 15 min after IR to assess recovery. Analyses with repeated-measures general linear models revealed a condition × time interaction for brachial artery flow-mediated dilation (FMD; P = 0.04), and no interaction effect was found for the near-infrared spectroscopy-derived reperfusion slope (P = 0.86). Follow-up analysis showed a significant decline in FMD following IR injury with BRplacebo in comparison with all other timepoints (all, P < 0.05), while this decline was not present with BRnitrate (all, P > 0.05). Our findings demonstrate that a single dose of dietary NO3- minimizes IR-induced macrovascular endothelial dysfunction in healthy, early postmenopausal women, but does not improve resting macrovascular and microvascular function. Trial registration number: NCT03644472. Novelty: In healthy, early postmenopausal women, a single dose of NO3--rich BR can protect against IR-induced endothelial dysfunction. This protection may be due to nitric oxide bioactivity during IR rather than improved endothelial function prior to the IR protocol per se.

Melatonin Alleviates Ovariectomy-Induced Cardiovascular Inflammation in Sedentary or Exercised Rats by Upregulating SIRT1

We aimed to evaluate the impact of hormone replacement, melatonin, or exercise alone or their combination on oxidative damage and functional status of heart, brain, and aorta of ovariectomized (OVX) rats and to determine whether the signaling pathway is dependent on sirtuin-1 (SIRT1). Ovariectomized Sprague Dawley rats were orally given either a hormone replacement therapy (1 mg/kg/day,17β estradiol; HRT) or melatonin (4 mg/kg/day) or HRT + melatonin treatments or tap water, while each group was further divided into sedentary and exercise (30 min/5 days/week) groups. After the heart rate measurements and memory tests were performed, trunk blood was collected at the end of the 10th week to determine metabolic parameters in serum samples. Tissue samples of abdominal aorta, heart, and brain were taken for biochemical measurements and histopathological evaluation. Heart rates and memory performances of the OVX rats were not changed significantly by none of the applications. Melatonin treatment or its co-administration with HRT upregulated the expressions of IL-10 and SIRT1, reduced the expressions of IL-6 and TNF-α, and reduced DNA damage in the hearts and thoracic aortae of non-exercised rats. Co-administration of melatonin and HRT to exercised OVX rats reduced inflammatory response and upregulated SIRT1 expression in the aortic and cardiac tissues. The present study suggests that melatonin treatment, either alone or in combination with exercise and/or HRT, upregulates SIRT1 expression and alleviates oxidative injury and inflammation in the hearts and aortas of OVX rats. Melatonin should be considered in alleviating cardiovascular disease risk in postmenopausal women.

Markers of oxidative stress in postmenopausal women with metabolic syndrome

During the postmenopausal period, there are metabolic alterations that predispose individuals to metabolic syndrome (MS), oxidative stress (OS), and the risk of developing cardiovascular diseases. We aimed to compare the concentrations of OS markers in postmenopausal women with and without MS. Malondialdehyde, carbonyl groups, and total antioxidant capacity (TAC) were quantified. We conducted a cross-sectional study: Group 1 (n = 42) included women without MS, and Group 2 (n = 58) comprised women with MS. Participants' age was similar between groups. Glucose, insulin, the homeostasis model assessment of insulin resistance, triglycerides, uric acid, and body mass index were significantly lower in postmenopausal women without MS. OS markers were significantly lower in Group 1 vs. Group 2: malondialdehyde, 31.32 ± 14.93 vs. 40.27 ± 17.62 pmol MDA/mg dry weight (p = .01); protein carbonylation, 6325 ± 1551 vs. 7163 ± 1029 pmol PC/mg protein (p = .0003); and TAC, 1497 ± 297.3 vs. 1619 ± 278.8 pmol Trolox equivalent/mg protein (p = .041). OS markers were significantly higher in postmenopausal women with MS. Impact statementWhat is already known on this subject? Oxidative stress has been implicated in numerous disease processes; however, information on the relationship between oxidative stress and metabolic syndrome among postmenopausal women remains limited.What do the results of this study add? Our results indicate that in postmenopausal Mexican women, oxidative stress markers were significantly lower in those without metabolic syndrome, whereas total antioxidant capacity was higher in those with metabolic syndrome, which could be explained as an antioxidant defense mechanism capable of neutralising excess oxidative damage markers.What are the implications of these findings for clinical practice and/or further research? This study is of interest to a broad audience because it compares the concentrations of oxidative stress markers in postmenopausal women with and without metabolic syndrome. Our study could support intervention with supplements or foods rich in antioxidants as lifestyle modifications in postmenopausal women with metabolic syndrome.