Association of hot flushes with ghrelin and adipokines in early versus late postmenopausal women

Obesity and menopause

Obesity is not a choice or a result of lack of willpower, but a multifactorial, chronic, progressive, and relapsing disease. During menopause, hormonal and body composition changes lead to greater visceral adiposity, that aggravates women's health at a cardiometabolic, mechanic and mental level. Adiposity has been identified as an important modifier of reproductive hormones. During female midlife, obesity has been associated with menstrual cycle alterations (anovulatory cycles ending with abnormal bleedings), menopausal symptoms including hot flashes, poor quality of sleep, aches and joint pain, genitourinary symptoms, and reduced quality of life. However, the relationships between weight, the menopausal process, aging, and hormone levels remain poorly understood. Women with obesity have an increased risk of thromboembolic disease when using menopause hormone therapy (MHT), and it is probably the main medical condition to prescribe or not MHT. However, this risk depends on the route and type of MHT. The use of estrogen-only or combined transdermal MHT does not increase the risk of a thrombotic event in women with obesity.

Comparison of leptin and estrone levels between normal body mass index and obese menopausal women

Postmenopausal women often experience hormonal changes and shifts in fat composition, affecting weight gain and obesity. Understanding the link between hormones, especially estrogen and leptin, is key to managing weight and lowering disease risk in menopausal women. The aim of this study was to compare the levels of leptin and estrone in menopausal women with normal weight and obesity. A cross-sectional study was conducted on menopausal women, either normal body mass index (BMI) or obese, at H. Adam Malik General Hospital, Medan, Indonesia. Blood samples were collected to measure leptin and estrone levels using the enzyme-linked immunosorbent assay (ELISA) method. The differences in leptin levels between groups were analyzed using the Wilcoxon test, while the correlation between BMI and leptin was examined using the Pearson correlation test. The disparity in estrone levels in both groups was analyzed using the Mann-Whitney test and the correlations between variables were assessed using the Spearman or Pearson correlation tests as appropriate. The mean leptin levels in normal BMI and obesity groups were 17.73±4.96 and 25.46±12.95 ng/mL, respectively, and were statistically different (p=0.006). The mean estrone levels in menopausal women with normal BMI and obesity were 943.23±391.79 and 851.38±282.23 ng/mol, respectively and were not statistically different (p=0.564). A significant positive correlation was found between BMI and leptin level (r=0.59; p<0.001), while BMI and estrone were not significantly correlated (r=0.083; p=0.559). In conclusion, leptin level was significantly different between BMI groups and had a strong positive correlation with BMI. This finding could be an important insight in body weight management and disease risk prevention in menopausal women.

Menopause Hot Flashes and Molecular Mechanisms Modulated by Food-Derived Nutrients

The causes of vasomotor symptoms, including hot flashes, are not fully understood, may be related to molecular factors, and have a polygenic architecture. Nutrients and bioactive molecules supplied to the body with food are metabolized using various enzymatic pathways. They can induce molecular cell signaling pathways and, consequently, activate effector proteins that modulate processes related to hot flashes in menopausal women. In this review, we analyzed the literature data from the last 5 years, especially regarding genome-wide association study (GWAS) analysis, and selected molecular factors and cell signaling pathways that may potentially be related to hot flashes in women. These are the kisspeptin-GnRH pathway, adipocyte-derived hormones, aryl hydrocarbon receptor signaling, catechol estrogens and estrogen sulfotransferase, inflammatory and oxidative stress biomarkers, and glucose availability. Then, single compounds or groups of food ingredients were selected that, according to experimental data, influence the course of the discussed molecular pathways and thus can be considered as potential natural therapeutic agents to effectively reduce the troublesome symptoms of menopause in women.

Menopausal vasomotor symptoms and adiponectin among midlife women

OBJECTIVE

Vasomotor symptoms (VMS) are prevalent symptoms that can have a negative impact on quality of life. VMS have also been linked to cardiovascular disease risk, yet the mechanisms underlying these associations have not been elucidated. Some initial works link VMS to adverse adipokine profiles or cytokines produced by adipose tissue. However, results are not entirely consistent and are based entirely on self-report VMS, which is influenced by a range of memory and reporting biases. The aim of this work was to test whether physiologically assessed VMS are associated with lower adiponectin, the most abundant adipokine in the body, controlling for confounding factors. We also consider whether adiponectin explains previously documented relationships between VMS and carotid atherosclerosis.

METHODS

A total of 300 peri- and postmenopausal nonsmoking women aged 40 to 60 years enrolled in the MsHeart study comprised the analytic sample. Women were free of hormone therapy or other medications impacting VMS, insulin-dependent diabetes, and cardiovascular disease. Participants underwent ambulatory physiologic VMS monitoring, physical measures, a carotid ultrasound, and fasting phlebotomy.

RESULTS

More frequent physiologically assessed VMS were associated with lower adiponectin ( B [SE] = -0.081 [0.028], P = 0.004; or 0.081 lower μg/mL in adiponectin for each additional VMS over 24 hours), controlling for age, race/ethnicity, education, insulin resistance, and waist circumference. Associations were not explained by endogenous estradiol. Adiponectin did not explain associations between VMS and carotid atherosclerosis.

CONCLUSIONS

Physiologic VMS were associated with lower adiponectin after considering potential confounders. The role of adipokines in VMS and in links between VMS and health warrants further attention.

Metabolically healthy and unhealthy obesity and risk of vasomotor symptoms in premenopausal women: cross-sectional and cohort studies

Objective

To examine the relationship between metabolically healthy and unhealthy obesity phenotypes and risk of vasomotor symptoms (VMS) in premenopausal women.

Design

Prospective cohort study.

Setting

Middle‐aged women in a cohort based on regular health screening examinations.

Population

Premenopausal Korean women aged 42–52 years were recruited and were followed up for a median of 4.2 years. The cross‐sectional and cohort studies comprised 4672 women and 2590 women without VMS at baseline, respectively.

Methods

Adiposity measures included body mass index (BMI), waist circumference and percentage body fat. Being metabolically healthy was defined as not having any metabolic syndrome components or a homeostasis model assessment of insulin resistance of 2.5 or more.

Main outcomes measures

VMS (hot flushes and night sweats) assessed using the questionnaire.

Results

All adiposity measures were positively associated with an increased risk of VMS in both cross‐sectional and longitudinal studies. The multivariable‐adjusted prevalence ratio (95% confidence interval [CI]) for VMS comparing percentage body fat of 35% or more with the reference was 1.47 (95% CI 1.14–1.90) in metabolically healthy women, and the corresponding prevalence ratio was 2.32 (95% CI 1.42–3.78) in metabolically unhealthy women (P_interaction = 0.334). The multivariable‐adjusted hazard ratio for incident VMS comparing percentage body fat of 35% or more with the reference was 1.34 (95% CI 1.00–1.79) in metabolically healthy women, whereas the corresponding hazard ratio was 3.61 (95% CI 1.81–7.20) in metabolically unhealthy women (P_interaction = 0.036). The association between BMI, waist circumference and VMS did not significantly differ by metabolic health status.

Conclusions

Maintaining normal weight and being metabolically healthy may help to prevent VMS in premenopausal women.

Tweetable abstract

Avoiding obesity and a metabolically unhealthy status may help reduce vasomotor symptoms in premenopausal women.

Avoiding obesity and a metabolically unhealthy status may help reduce vasomotor symptoms in premenopausal women.

Factors associated with high placebo response in clinical studies of hot flashes: a meta-analysis

IMPORTANCE

High placebo response can often mask the evaluation of active treatment in clinical studies for women with hot flashes and potentially undermine the evaluation of new treatments.

OBJECTIVE

The aim of this meta-analysis was to determine the factors associated with high placebo response (defined as the reduction in the mean number of hot flash frequency from baseline) in randomized, controlled, double-blind studies enrolling women with hot flashes.

EVIDENCE REVIEW

To identify eligible studies, Embase, MEDLINE, and BIOSIS Previews were searched for English-language articles published between April 1975 and August 2020. Placebo-controlled, double-blind, randomized studies that assessed changes in hot flash frequency were included if they satisfied the defined criteria. We conducted univariate and multivariate analyses using categorical and numerical data. Categorical data included the following variables and levels in brackets: active treatment type (hormone therapy /non- hormone therapy /complementary and alternative medicine), administration route (oral/non-oral), study region (in/excluded the US), breast cancer population (in/excluded), entry criteria of hot flash severity (moderate to severe only/all included), parallel or crossover study, placebo run-in period before treatment (yes/no), and menopausal status (postmenopausal only/include perimenopausal/include premenopausal). Numerical data included published year, pretreatment period duration, treatment period duration, number of sites, number of total participants, number of placebo participants, number of treatment arms, mean age, BMI, and hot flash frequency at baseline.

FINDINGS

Forty-three of the 802 identified publications were included in the review. Multivariate analysis identified three individual factors associated with high placebo response: treatment period duration, number of treatment arms, and BMI.

CONCLUSIONS AND RELEVANCE

We identified several factors associated with high placebo response in clinical studies of women with hot flashes. Knowing these factors may enable proactive implementation of operational and analytic strategies that further aid in determining the true treatment effect of an intervention.

Ghrelin promotes the osteogenic differentiation of rMSCs via miR-206 and the ERK1/2 pathway

OBJECTIVE

Mesenchymal stem cells (MSCs) can differentiate into chondroblasts, adipocytes, or osteoblasts under appropriate stimulation. Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor (GHSR), stimulates growth hormone (GH) secretion and exerts both orexigenic and adipogenic effects. The ERK1/2 signaling pathway is known to trigger osteogenic differentiation of rabbit bone marrow-derived mesenchymal stromal cells. In the present study, the function of miR-206 in the ghrelin-mediated osteogenic differentiation of rabbit bone marrow-derived mesenchymal stromal cells (rMSCs) was explored.

METHODS

The expression of miR-206 was detected by qPCR, and phosphorylated ERK1/2 and the protein expression levels of ALP, RUNX2, and Osterix were assessed by western blotting.

RESULTS

Ghrelin inhibited the expression of miR-206 to promote the osteogenic differentiation of rMSCs. Moreover, ghrelin increased the phosphorylation of ERK1/2, while overexpression of miR-206 suppressed ERK1/2 phosphorylation, indicating that miR-206 can regulate the ERK1/2 pathway. Further, inhibition of ERK1/2 had no influence on miR-206 expression; however, the phosphorylation of ERK1/2 was decreased, and the protein expression levels of ALP, RUNX2, and Osterix were downregulated.

CONCLUSIONS

Ghrelin promotes the osteogenic differentiation of rMSCs via miR-206 and the ERK1/2 pathway.