Effect of postmenopausal hormone therapy on glucose and insulin concentrations. PEPI Investigators. Postmenopausal Estrogen/Progestin Interventions

An estrogen receptor α-derived peptide improves glucose homeostasis during obesity

Estrogen receptor α (ERα) plays a crucial role in regulating glucose and energy homeostasis during type 2 diabetes mellitus (T2DM). However, the underlying mechanisms remain incompletely understood. Here we find a ligand-independent effect of ERα on the regulation of glucose homeostasis. Deficiency of ERα in the liver impairs glucose homeostasis in male, female, and ovariectomized (OVX) female mice. Mechanistic studies reveal that ERα promotes hepatic insulin sensitivity by suppressing ubiquitination-induced IRS1 degradation. The ERα 1-280 domain mediates the ligand-independent effect of ERα on insulin sensitivity. Furthermore, we identify a peptide based on ERα 1-280 domain and find that ERα-derived peptide increases IRS1 stability and enhances insulin sensitivity. Importantly, administration of ERα-derived peptide into obese mice significantly improves glucose homeostasis and serum lipid profiles. These findings pave the way for the therapeutic intervention of T2DM by targeting the ligand-independent effect of ERα and indicate that ERα-derived peptide is a potential insulin sensitizer for the treatment of T2DM.

Reproductive risk factors across the female lifecourse and later metabolic health

Metabolic health is characterized by optimal blood glucose, lipids, cholesterol, blood pressure, and adiposity. Alterations in these characteristics may lead to the development of type 2 diabetes mellitus or dyslipidemia. Recent evidence suggests that female reproductive characteristics may be overlooked as risk factors that contribute to later metabolic dysfunction. These reproductive traits include the age at menarche, menstrual irregularity, the development of polycystic ovary syndrome, gestational weight change, gestational dysglycemia and dyslipidemia, and the severity and timing of menopausal symptoms. These risk factors may themselves be markers of future dysfunction or may be explained by shared underlying etiologies that promote long-term disease development. Disentangling underlying relationships and identifying potentially modifiable characteristics have an important bearing on therapeutic lifestyle modifications that could ease long-term metabolic burden. Further research that better characterizes associations between reproductive characteristics and metabolic health, clarifies underlying etiologies, and identifies indicators for clinical application is warranted in the prevention and management of metabolic dysfunction.

Sesamin ameliorates lipotoxicity and lipid accumulation through the activation of the estrogen receptor alpha signaling pathway

Nonalcoholic fatty liver disease (NAFLD) has been linked to fat accumulation in the liver and lipid metabolism imbalance. Sesamin, a lignan commonly found in sesame seed oil, possesses antioxidant, anti-inflammatory, and anticancer properties. However, the precise mechanisms by which sesamin prevents hepatic steatosis are not well understood. This study aimed to explore the molecular mechanisms by which sesamin may improve lipid metabolism dysregulation. A in vitro hepatic steatosis model was established by exposing HepG2 cells to palmitate sodium. The results showed that sesamin effectively mitigated lipotoxicity and reduced reactive oxygen species production. Additionally, sesamin suppressed lipid accumulation by regulating key factors involved in lipogenesis and lipolysis, such as fatty acid synthase (FASN), sterol regulatory element-binding protein 1c (SREBP-1c), forkhead box protein O-1, and adipose triglyceride lipase. Molecular docking results indicated that sesamin could bind to estrogen receptor α (ERα) and reduce FASN and SREBP-1c expression via the Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ)/AMP-activated protein kinase (AMPK) signaling pathway. Sesamin attenuated palmitate-induced lipotoxicity and regulated hepatic lipid metabolism in HepG2 cells by activating the ERα/CaMKKβ/AMPK signaling pathway. These findings suggest that sesamin can improve lipid metabolism disorders and is a promising candidate for treating hepatic steatosis.

Cardiometabolic health, menopausal estrogen therapy and the brain: How effects of estrogens diverge in healthy and unhealthy preclinical models of aging

Research in preclinical models indicates that estrogens are neuroprotective and positively impact cognitive aging. However, clinical data are equivocal as to the benefits of menopausal estrogen therapy to the brain and cognition. Pre-existing cardiometabolic disease may modulate mechanisms by which estrogens act, potentially reducing or reversing protections they provide against cognitive decline. In the current review we propose mechanisms by which cardiometabolic disease may alter estrogen effects, including both alterations in actions directly on brain memory systems and actions on cardiometabolic systems, which in turn impact brain memory systems. Consideration of mechanisms by which estrogen administration can exert differential effects dependent upon health phenotype is consistent with the move towards precision or personalized medicine, which aims to determine which treatment interventions will work for which individuals. Understanding effects of estrogens in both healthy and unhealthy models of aging is critical to optimizing the translational link between preclinical and clinical research.

Continuous glucose monitoring in a healthy population: understanding the post-prandial glycemic response in individuals without diabetes mellitus

Continuous glucose monitoring has become a common adjunct in the management of Diabetes Mellitus. However, there has been a recent trend among individuals without diabetes using these devices as a means of monitoring their health. The increased visibility of glucose data has allowed users to study the effect lifestyle has upon post-prandial glucose levels. Although post-prandial hyperglycemia is well understood in the setting of diabetes, its impact in individuals without diabetes is less well defined. This article reviews the factors which contribute to post-prandial hyperglycemia in individuals without diabetes and how the data obtained from continuous glucose monitoring can be used to improve an individual's metabolic health.

Sex Hormones and Diabetes in 45- to 74-year-old Men and Postmenopausal Women: The Hispanic Community Health Study

Previous studies demonstrated associations of endogenous sex hormones with diabetes. Less is known about their dynamic relationship with diabetes progression through different stages of the disease, independence of associations, and role of the hypothalamic-pituitary gonadal axis. The purpose of this analysis was to examine relationships of endogenous sex hormones with incident diabetes, prediabetes, and diabetes traits in 693 postmenopausal women and 1015 men aged 45 to 74 years without diabetes at baseline participating in the Hispanic Community Health Study/Study of Latinos and followed for 6 years. Baseline hormones included estradiol, luteinizing hormone (LH), follicle stimulating hormone (FSH), sex hormone-binding globulin (SHBG), dehydroepiandrosterone sulfate (DHEAS), and, in men, testosterone and bioavailable testosterone. Associations were analyzed using multivariable Poisson and linear regressions. In men, testosterone was inversely associated with conversion from prediabetes to diabetes (incidence rate ratio [IRR] for 1 SD increase in testosterone: 0.821; 95% CI, 0.676, 0.997; P = 0.046), but not conversion from normoglycemia to prediabetes. Estradiol was positively associated with increase in fasting insulin and homeostatic model assessment of insulin resistance. In women, SHBG was inversely associated with change in glycosylated hemoglobin, postload glucose, and conversion from prediabetes to diabetes (IRR = 0.62; 95% CI, 0.44, 0.86, P = 0.005) but not from normoglycemia to prediabetes. Relationships with other hormones varied across glycemic measures. Stronger associations of testosterone and SHBG with transition from prediabetes to diabetes than from normoglycemic to prediabetes suggest they are operative at later stages of diabetes development. Biologic pathways by which sex hormones affect glucose homeostasis await future studies.

The influence of 17β-estradiol plus norethisterone acetate treatment on markers of glucose and insulin metabolism in women: a systematic review and meta-analysis of randomized controlled trials

Objective

Despite the fact that some evidence suggests that the administration of 17β-estradiol plus norethisterone acetate influences glucose and insulin metabolism in women, these findings are still contradictory. Thus, we aimed to examine the impact of the co-administration of 17β-estradiol and norethisterone acetate on glycated haemoglobin (HbA1c), fasting glucose, insulin and C-peptide concentrations in females by means of a systematic review and meta-analysis of randomized controlled trials (RCTs).

Methods

We searched four databases (PubMed/MEDLINE, Scopus, Embase, and Web of Science) using specific keywords and word combinations. The random-effects model (DerSimonian and Laird model) was employed to compute the weighted mean difference (WMD) and 95% confidence intervals (CIs) for the variations from baseline of HbA1c, fasting glucose, insulin, and C-peptide concentrations.

Results

In total, 14 RCTs were entered into the quantitative synthesis. The combined administration of 17β-estradiol and norethisterone acetate decreased HbA1c (WMD: -0.65%, 95% CI: -1.15 to -0.15; P=0.011), fasting glucose (WMD: -11.05 mg/dL, 95% CI: -16.6 to -5.5; P<0.001) and insulin (WMD: -1.35 mIU/L, 95% CI: -2.20 to -0.50; P=0.001) levels. C-peptide concentrations' declined only in females diagnosed with overweight/obesity or diabetes.

Conclusion

Evidence to date points out that the administration of 17β-estradiol and norethisterone acetate has a positive impact on glucose metabolism in women by reducing fasting glucose, HbA1c, and insulin values. Future studies need to confirm the potential benefits of this drug combination in the prevention and/or management of cardiometabolic disorders.

Association of Menopausal Hormone Therapy with Risk of Pancreatic Cancer: A Systematic Review and Meta-analysis of Cohort Studies

BACKGROUND

Although menopausal hormone therapy (MHT) is commonly prescribed, little is known about the association between MHT use and risk of pancreatic cancer.

METHODS

We searched PubMed, Embase, and Cochrane Library, from inception until April 20, 2022. The risk of bias was assessed with the Newcastle-Ottawa Quality Assessment Scale. Pooled relative risks (RR) for pancreatic cancer risk were calculated using random-effects models. We computed prediction intervals (PI) and performed subgroup meta-analyses. Meta-regression was performed to investigate the sources of heterogeneity.

RESULTS

This study included 2,712,313 women from 11 cohort studies. There was no association between MHT and pancreatic cancer risk (RR, 0.92; 95% confidence interval (CI), 0.83-1.02; I2, 64%; 95% PI, 0.68-1.25). Subgroup meta-analyses of four studies stratified by MHT formulations showed inverse associations with the risk of pancreatic cancer (women receiving estrogen-only MHT: RR, 0.77; 95% CI, 0.64-0.94; I2, 57%; estrogen plus progestin MHT: RR, 0.85; 95% CI, 0.75-0.96; I2, 0%). Subgroup analysis defined by recency and duration of treatment did not reveal evidence of associations between MHT and pancreatic cancer risk.

CONCLUSIONS

This study found no association between the overall use of MHT and risk of pancreatic cancer. However, among four studies with data on MHT formulations, subgroup analysis showed a decreased risk of pancreatic cancer among users of estrogen-only and combined estrogen-progestin therapy. Owing to the inconsistent findings between our main and subgroup analyses, future studies stratified by MHT formulations are warranted.

IMPACT

The findings of this study indicate that future investigation should focus on MHT formulations.

Associations Between Midlife Menopausal Hormone Therapy Use, Incident Diabetes, and Late Life Memory in the Wisconsin Longitudinal Study

BACKGROUND

Prior research suggests a link between menopausal hormone therapy (MHT) use, memory function, and diabetes risk. The menopausal transition is a modifiable period to enhance long-term health and cognitive outcomes, although studies have been limited by short follow-up periods precluding a solid understanding of the lasting effects of MHT use on cognition.

OBJECTIVE

We examined the effects of midlife MHT use on subsequent diabetes incidence and late life memory performance in a large, same-aged, population-based cohort. We hypothesized that the beneficial effects of MHT use on late life cognition would be partially mediated by reduced diabetes risk.

METHODS

1,792 women from the Wisconsin Longitudinal Study (WLS) were included in analysis. We employed hierarchical linear regression, Cox regression, and causal mediation models to test the associations between MHT history, diabetes incidence, and late life cognitive performance.

RESULTS

1,088/1,792 women (60.7%) reported a history of midlife MHT use and 220/1,792 (12.3%) reported a history of diabetes. MHT use history was associated with better late life immediate recall (but not delayed recall), as well as a reduced risk of diabetes with protracted time to onset. Causal mediation models suggest that the beneficial effect of midlife MHT use on late life immediate recall were at least partially mediated by diabetes risk.

CONCLUSION

Our data support a beneficial effect of MHT use on late life immediate recall (learning) that was partially mediated by protection against diabetes risk, supporting MHT use in midlife as protective against late life cognitive decline and adverse health outcomes.

A researcher's guide to preclinical mouse NASH models

Non-alcoholic fatty liver disease (NAFLD) and its inflammatory form, non-alcoholic steatohepatitis (NASH), have quickly risen to become the most prevalent chronic liver disease in the Western world and are risk factors for the development of hepatocellular carcinoma (HCC). HCC is not only one of the most common cancers but is also highly lethal. Nevertheless, there are currently no clinically approved drugs for NAFLD, and NASH-induced HCC poses a unique metabolic microenvironment that may influence responsiveness to certain treatments. Therefore, there is an urgent need to better understand the pathogenesis of this rampant disease to devise new therapies. In this line, preclinical mouse models are crucial tools to investigate mechanisms as well as novel treatment modalities during the pathogenesis of NASH and subsequent HCC in preparation for human clinical trials. Although, there are numerous genetically induced, diet-induced and toxin-induced models of NASH, not all of these models faithfully phenocopy and mirror the human pathology very well. In this Perspective, we shed some light onto the most widely used mouse models of NASH and highlight some of the key advantages and disadvantages of the various models with an emphasis on 'Western diets', which are increasingly recognized as some of the best models in recapitulating the human NASH pathology and comorbidities.

The interplay between diabetes mellitus and menopause: clinical implications

The menopausal transition is an impactful period in women's lives, when the risk of cardiovascular disease is accelerated. Similarly, diabetes mellitus profoundly impacts cardiovascular risk. However, the interplay between menopause and diabetes mellitus has not been adequately studied. The menopausal transition is accompanied by metabolic changes that predispose to diabetes mellitus, particularly type 2 diabetes mellitus (T2DM), as menopause results in increased risk of upper body adipose tissue accumulation and increased incidence of insulin resistance. Equally, diabetes mellitus can affect ovarian ageing, potentially causing women with type 1 diabetes mellitus and early-onset T2DM to experience menopause earlier than women without diabetes mellitus. Earlier age at menopause has been associated with a higher risk of T2DM later in life. Menopausal hormone therapy can reduce the risk of T2DM and improve glycaemic control in women with pre-existing diabetes mellitus; however, there is not enough evidence to support the administration of menopausal hormone therapy for diabetes mellitus prevention or control. This Review critically appraises studies published within the past few years on the interaction between diabetes mellitus and menopause and addresses all clinically relevant issues, such as the effect of menopause on the development of T2DM, and the management of both menopause and diabetes mellitus.

Estrogen receptor α activation modulates the gut microbiome and type 2 diabetes risk factors

Estradiol and exercise can decrease risk factors associated with type 2 diabetes (T2D) including total body weight gain and abdominal fat gain. Estradiol functions through estrogen receptor (ER) α and ERβ. Some studies suggest that activation of ERα may provide protection against T2D. Female Wistar rats were ovariectomized and fed a high‐fat diet for 10 weeks and divided into the following 5 experimental groups: (1) no treatment (control), (2) exercise, (3) estradiol, (4) propylpyrazoletriyl (a selective ERα agonist), and (5) diarylpropionitrile (a selective ERβ agonist). ERα activation decreased the abundance of Firmicutes, and ERα and ERβ activation increased the abundance of Bacteroidetes. ERα activation decreased food consumption, and ERα and ERβ activation increased voluntary activity. Exercise was the only treatment to decrease the blood glucose and serum insulin levels. ERα activation, but not ERβ, increased hepatic protein expression of ACC and FAS and decreased hepatic protein expression of LPL. ERα activation also decreased hepatic mRNA expression of PPARα and PPARγ. This study elucidates the functions of estradiol by assessing specific activation of ERα and ERβ. As obesity increases the abundance of Firmicutes and decreases the abundance of Bacteroidetes, our study shows that ERα activation can restore the gut microbiome to non‐obese abundances. This study further provides novel insights into ERα’s role in hepatic fat metabolism via regulation of ACC, FAS, LPL, PPARα, and PPARγ.

Change in metabolic parameters and reproductive hormones from baseline to 6-month hormone therapy

Adequate evidence showed hormone therapy (HT) reduces the risk of new-onset diabetes in midlife women by decreasing fasting glucose and insulin. However, the improvement of these diabetic biomarkers varied with each individual in clinical observations. The objective of our study was to investigate potential baseline factors associated with the change of fasting glucose and insulin during HT.A retrospective cohort study was performed among 263 midlife participants aged 40 to 60 years with menopausal symptoms who have received 6-month individualized HT. Demographic information and laboratory indicators including reproductive hormone, lipid profiles, diabetic indicators were collected and measured at baseline and were followed-up. A series of statistical analyses were performed to confirm the effectiveness of HT and compare the baseline factors between participants with different glycemic or insulinemic response. Multivariable linear regression model with stepwise variable selection was further used to identify the associated factor with the change of fasting glucose and insulin.Of all participants, fasting glucose (P = .001) and fasting insulin (P < .001) were significantly decreased after individualized HT. Significant differences in baseline reproductive hormones were observed in participants with different glycemic response to HT (P < .001 for both follicle stimulating hormone [FSH] and estradiol). Stepwise linear regression model showed that in addition to baseline fasting glucose levels, baseline FSH was also independently associated with the change of fasting glucose (β = -0.145, P = .019 for baseline FSH) but not fasting insulin. Greater reduction in fasting glucose in women with higher FSH levels was observed even though they have already been in better metabolic conditions (P = .037).Midlife women with higher baseline FSH levels have greater reduction in fasting glucose but not fasting insulin. FSH could be an independent predictor of glycemic response to HT in peri- and postmenopausal women.

Exercise prevents whole body type 2 diabetes risk factors better than estradiol replacement in rats

The absence of estrogens in postmenopausal women is linked to an increased risk of type 2 diabetes (T2D) and estradiol replacement can decrease this risk. Notably, exercise can also treat and prevent T2D. This study seeks to understand the molecular mechanisms by which estradiol and exercise induce their beneficial effects via assessing whole body and cellular changes. Female Wistar rats were ovariectomized and fed a high-fat diet for 10 wk and divided into the following four experimental groups: 1) no treatment (control), 2) exercise (Ex), 3) estradiol replacement, and 4) Ex + estradiol. Both Ex and estradiol decreased the total body weight gain. However, only exercise effectively reduced the white adipose tissue (WAT) weight gain, food intake, blood glucose levels, and serum insulin levels. At the molecular level, exercise increased the noninsulin-stimulated pAkt levels in the WAT. In the liver, estradiol increased the protein expression of acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) and estradiol decreased the hepatic protein expression of lipoprotein lipase (LPL). In the WAT, estradiol and exercise increased the protein expression of adipose triglyceride lipase (ATGL). Exercise provides better protection against T2D when considering whole body measurements, which may be due to increased noninsulin-stimulated pAkt in the WAT. However, at the cellular level, several molecular changes in fat metabolism and fat storage occurred in the liver and WAT with estradiol treatment.NEW & NOTEWORTHY Exercise provides better protection than estradiol against type 2 diabetes when considering whole body measurements including adipose tissue weight, blood glucose levels, and serum insulin levels, which may be due to increased noninsulin-stimulated pAkt in the adipose tissue. However, at the cellular level, several molecular changes in fat metabolism and fat storage occurred in the liver and adipose tissue with estradiol treatment.

Menopause and cardiometabolic diseases: What we (don't) know and why it matters

This narrative review discusses the current understanding, knowledge gaps and challenges in expanding our knowledge of the association between menopause and the reproductive aging process and cardiometabolic disease (CMD) in women, with a focus on type 2 diabetes and cardiovascular disease. The physiological changes that occur at different stages of the reproductive life span, as well as type of menopause and timing, are factors widely associated with CMD risk; however, the underlying mechanisms remain either unclear or insufficiently studied. Decreased ovarian estrogen production and relative androgen excess around menopause onset are the most studied factors linking menopause and cardiometabolic health; nevertheless, the evidence is not persuasive and other hypotheses might explain the changes in CMD risk during menopausal transition. In this context, hormone therapy has been widely adopted in the treatment and prevention of CMD, although uncertainty regarding its cardiometabolic effects has raised the need to optimize therapeutic modalities. Mechanisms such as the "iron overload theory" and new "omics" platforms could provide new insights into potential pathways underlying the association between menopause and cardiometabolic health, such as the DNA damage response. Although it has been widely reported that environmental and lifestyle factors affect both menopause and cardiometabolic health, there is little evidence on the role of these exposures in menopause-associated CMD risk.

Hormone therapy in the postmenopausal years: considering benefits and risks in clinical practice

BACKGROUND

Menopausal symptoms can be very distressing and considerably affect a woman's personal and social life. It is becoming more and more evident that leaving bothersome symptoms untreated in midlife may lead to altered quality of life, reduced work productivity and, possibly, overall impaired health. Hormone therapy (HT) for the relief of menopausal symptoms has been the object of much controversy over the past two decades. At the beginning of the century, a shadow was cast on the use of HT owing to the concern for cardiovascular and cerebrovascular risks, and breast cancer, arising following publication of a large randomized placebo-controlled trial. Findings of a subanalysis of the trial data and extended follow-up studies, along with other more modern clinical trials and observational studies, have provided new evidence on the effects of HT.

OBJECTIVE AND RATIONALE

The goal of the following paper is to appraise the most significant clinical literature on the effects of hormones in postmenopausal women, and to report the benefits and risks of HT for the relief of menopausal symptoms.

SEARCH METHODS

A Pubmed search of clinical trials was performed using the following terms: estrogens, progestogens, bazedoxifene, tibolone, selective estrogen receptor modulators, tissue-selective estrogen complex, androgens, and menopause.

OUTCOMES

HT is an effective treatment for bothersome menopausal vasomotor symptoms, genitourinary syndrome, and prevention of osteoporotic fractures. Women should be made aware that there is a small increased risk of stroke that tends to persist over the years as well as breast cancer risk with long-term estrogen-progestin use. However, healthy women who begin HT soon after menopause will probably earn more benefit than harm from the treatment. HT can improve bothersome symptoms, all the while conferring offset benefits such as cardiovascular risk reduction, an increase in bone mineral density and a reduction in bone fracture risk. Moreover, a decrease in colorectal cancer risk is obtainable in women treated with estrogen-progestin therapy, and an overall but nonsignificant reduction in mortality has been observed in women treated with conjugated equine estrogens alone or combined with estrogen-progestin therapy. Where possible, transdermal routes of HT administration should be preferred as they have the least impact on coagulation. With combined treatment, natural progesterone should be favored as it is devoid of the antiapoptotic properties of other progestogens on breast cells. When beginning HT, low doses should be used and increased gradually until effective control of symptoms is achieved. Unless contraindications develop, patients may choose to continue HT as long as the benefits outweigh the risks. Regular reassessment of the woman's health status is mandatory. Women with premature menopause who begin HT before 50 years of age seem to have the most significant advantage in terms of longevity.

WIDER IMPLICATIONS

In women with bothersome menopausal symptoms, HT should be considered one of the mainstays of treatment. Clinical practitioners should tailor HT based on patient history, physical characteristics, and current health status so that benefits outweigh the risks.

The use of oral contraceptive is inversely associated with the risk of type 2 diabetes mellitus among middle-aged women

OBJECTIVE

To assess the cross-sectional association between oral contraceptive (OC) use and type 2 diabetes mellitus (T2DM) risk among US women.

METHODS

The data was obtained from the National Health and Nutrition Examination Survey (NHANES 2007-2018). OC use was assessed by questionnaires and the diagnosis of T2DM was confirmed by the glycosylated hemoglobin, fasting blood glucose, and self-report. Binary logistic regression models and the restricted cubic spline model were adopted to evaluate whether OC use was associated with T2DM.

RESULTS

Compared with non-users, the odds ratio (OR) with 95% confidence interval (CI) of T2DM risk for the OC users was 0.71 (0.57-0.89) in unadjusted Model. The association remained significant in fully adjusted models, and the OR with 95%CI was 0.78 (0.62-0.99). In the stratified analyses, there was an inverse association of OC use with T2DM risk when women were overweight. Dose-response analysis also revealed an inversely nonlinear relationship between the duration of OC use and T2DM (p-value for linearity = .589).

CONCLUSIONS

Our findings suggested that OC use may be inversely associated with T2DM risk.

Sex hormones, vascular factors and cognition

After more than a century of research, we have failed to develop a pharmacological prevention or cure for dementia. There are strong indicators that sex hormones influence cognition. In this paper we discuss the role of these hormones at the intersection between vascular disease and dementia, in light of the mounting literature covering the shared risk factors, pathological features alongside the timeline of hormonal change with the evolution of vascular and neurodegenerative disease. Interactive risk factors and the role of inflammation over the duration of disease evolution are highlighted. Our summary tables assessing the impact of estrogen-based hormone therapy on cognition over the past 45 years illustrate the effort expended to determine the ideal age for intervention and the type, dose, administration, and duration of therapy that might improve or protect cognition as well as alleviate menopausal symptoms. As the prevalence of dementia is rising and is higher in women, it is crucial we advance our knowledge from the "inconclusive" position statement on menopausal hormone therapy of the US Preventive Services Task Force.

Effects of hormone replacement therapy on glucose and lipid metabolism in peri- and postmenopausal women with a history of menstrual disorders

BACKGROUND

Previous studies have indicated that women with a history of menstrual disorders have an increased risk of metabolic and cardiovascular diseases. This has been attributed to the high proportion of polycystic ovary syndrome (PCOS) among this group. The favorable effects of hormone replacement therapy (HRT) on serum lipid profiles and glucose homeostasis in postmenopausal women is widely accepted. Whether HRT can also show positive effects on metabolic homeostasis in menopausal women with prior menstrual disorders (a putative PCOS phenotype) has not been reported yet. The aim of the study was to compare the effects of HRT on glucose and lipid metabolism in peri- and postmenopausal women with prior menstrual disorders and controls who did not have prior menstrual disorders.

METHODS

A retrospective multicenter study was conducted including 595 peri- and postmenopausal women who received HRT at four hospitals in the Zhejiang Province from May 31, 2010 to March 8, 2021. Participants were divided into the Normal menstruation group and the Menstrual disorders group according to their prior usual menstrual cycle pattern. Glucose and lipid metabolism indicators were assessed at baseline and after HRT. The results were compared between and within the groups, and data from peri- and postmenopausal women were analyzed separately.

RESULTS

HRT significantly decreased fasting insulin and homeostasis model assessment of insulin resistance in perimenopausal users, and fasting plasma glucose levels in postmenopausal users with prior menstrual disorders, compared with baseline. Furthermore, HRT decreased low-density lipoprotein cholesterol, total cholesterol, fasting insulin, fasting plasma glucose and homeostasis model assessment of insulin resistance in both peri- and postmenopausal controls, compared with baseline. Nevertheless, no significant differences were observed in any of the glucose or lipid metabolism indicators at baseline and follow-up, as well as changes from baseline levels between menopausal women with and without prior menstrual disorders.

CONCLUSIONS

HRT shows more obvious within-group improvements in glucose and lipid metabolism in controls, but there is no significant between-group difference. Further prospective studies are required for confirmation.

Effect of bariatric surgery on endogenous sex hormones and sex hormone-binding globulin levels: a systematic review and meta-analysis

BACKGROUND

Most studies have shown beneficial effect of bariatric surgery (BS) on serum levels of sex hormones.

OBJECTIVE

A systematic review and meta-analysis was conducted to examine the magnitude of possible changes in levels of sex hormones following BS.

SETTINGS

Electronic databases were searched, including PubMed, Scopus, Web of Science, and Embase, for relevant studies.

METHODS

The heterogeneity of the studies was examined by χ² tests and the degree of heterogeneity was estimated using I² statistic.

RESULTS

The results of pooled analyses revealed that BS caused a significant increase in luteinizing hormone (LH), follicular stimulating hormone (FSH), total testosterone (TT), and sex hormone binding globulin (SHBG) levels and conversely, decreased dehydroepiandrosterone (DHEA) and estradiol (E2) levels in males. For females, BS significantly increased LH, FSH, and SHBG levels and conversely, decreased androstenedione (AE), E2 and TT levels. Additionally, the level of progesterone (P), prolactin (PRL), free testosterone (FT) and dehydroepiandrosterone sulfate (DHEA-S) showed no significant changes in patients who had undergone BS.

CONCLUSION

BS changed most sex hormones levels including LH, FSH, TT, SHBG, AE, DHEA, and E2. It seems that BS is able to exert substantial impacts on sex hormones levels and as well as sexual function, however, larger, and more precise trials are required to specifically focus on these claims.

The midlife transition and the risk of cardiovascular disease and cancer Part I: magnitude and mechanisms

Heart disease and cancer are the leading causes of death in the United States. In women, the clinical appearance of both entities-coronary heart disease and cancer (breast, endometrium, and ovary)-escalate during the decades of the midlife transition encompassing the menopause. In addition to the impact of aging, during the interval between the age of 40 and 65 years, the pathophysiologic components of metabolic syndrome also emerge and accelerate. These include visceral adiposity (measured as waist circumference), hypertension, diabetes, and dyslipidemia. Osteoporosis, osteoarthritis, sarcopenia, depression, and even cognitive decline and dementia appear, and most, if not all, are considered functionally related. Two clinical reports confirm the interaction linking the emergence of disease: endometrial cancer and metabolic syndrome. One describes the discovery of unsuspected endometrial cancer in a large series of elective hysterectomies performed in aged and metabolically susceptible populations. The other is from the Women's Health Initiative Observational Study, which found a positive interaction between endometrial cancer and metabolic syndrome regardless of the presence or absence of visceral adiposity. Both provide additional statistical support for the long-suspected causal interaction among the parallel but variable occurrence of these common entities-visceral obesity, heart disease, diabetes, cancer, and the prevalence of metabolic syndrome. Therefore, 2 critical clinical questions require analysis and answers: 1: Why do chronic diseases of adulthood-metabolic, cardiovascular, endocrine-and, in women, cancers of the breast and endometrium (tissues and tumors replete with estrogen receptors) emerge and their incidence trajectories accelerate during the postmenopausal period when little or no endogenous estradiol is available, and yet the therapeutic application of estrogen stimulates their appearance? 2: To what extent should identification of these etiologic driving forces require modification of the gynecologist's responsibilities in the care of our patients in the postreproductive decades of the female life cycle? Part l of this 2-part set of "expert reviews" defines the dimensions, gravity, and interactive synergy of each clinical challenge gynecologists face while caring for their midlife (primarily postmenopausal) patients. It describes the clinically identifiable, potentially treatable, pathogenic mechanisms driving these threats to quality of life and longevity. Part 2 (accepted, American Journal of Obstetrics & Gynecology) identifies 7 objectives of successful clinical care, offers "triage" prioritization targets, and provides feasible opportunities for insertion of primary preventive care initiatives. To implement these goals, a reprogrammed, repurposed office visit is described.

Diabetes in Menopause: Risks and Management

The aim of this review is to present, critically appraise and qualitatively synthesize current evidence on the risk of type 2 diabetes mellitus (T2DM) development during menopause, the management of climacteric symptoms in women with T2DM and the management of T2DM in postmenopausal women. Menopause represents the end of reproductive life in women, as a result of ovarian aging. It is characterized by substantial decrease in the endogenous oestrogen concentrations and it is accompanied by alterations in body weight, adipose tissue distribution and energy expenditure, as well as insulin secretion, insulin sensitivity and activity that can predispose to the development of T2DM, independently of, and additively to, aging. Many women in midlife experience climacteric symptoms, including hot flushes and night sweats, resulting in an indication to receive Hormone Replacement Treatment (HRT). HRT has a favourable effect on glucose homeostasis both in women without and with T2DM. The latter was considered in the past as a cardiovascular disease (CVD) equivalent, which would suggest that women with the disease should not receive HRT. However, nowadays evidence exists to support an individualized approach of women based on their CVD risk, as some women with T2DM may be excellent candidates for HRT. Regarding T2DM management for women in menopause, lifestyle intervention, including diet and exercise, constitutes its cornerstone. However, most of these women will eventually require pharmacologic therapy. The most suitable agents should be selected according to their metabolic, cardiovascular and bone effects, taking into consideration the specific characteristics and comorbidities of each postmenopausal woman.

Impact of contraception and IVF hormones on metabolic, endocrine, and inflammatory status

Assisted reproductive technologies (ART) represent commonly utilized management strategies for infertility with multifactorial causes (including genetically predisposed diseases). Amongst ART, in vitro fertilization (IVF) is the most popular. IVF treatment may predispose the mother to increased risks and complications during pregnancy, and there may be adverse fetal outcomes. Hormonal therapies, including oral contraceptives, may impair glucose and lipid metabolism, and promote insulin resistance and inflammation. IVF treatment involves administration of reproductive hormones, similar in composition but in much higher doses than those used for oral contraception. The provision of IVF reproductive hormones to mice associates with glucose intolerance. In addition, the physiological and hormonal changes of pregnancy can trigger an inflammatory response, and metabolic and endocrine changes. There is controversy regarding the potential effects of IVF hormonal therapies in the promotion of diabetogenic and inflammatory states, additional to those that occur during pregnancy, and which may therefore predispose women with IVF-conceived pregnancies to adverse obstetric outcomes compared with women with spontaneously conceived pregnancies. This review summarizes the limited published evidence regarding the effect of IVF-based fertility therapies on glucose homeostasis, insulin resistance, cardio-metabolic profile, and markers of inflammation.

A randomized trial on the effect of oral combined estradiol and drospirenone on glucose and insulin metabolism in healthy menopausal women with a normal oral glucose tolerance test

BACKGROUND

Menopause is often associated with a central accumulation of body fat. This provokes insulin resistance. The resulting hyperinsulinemia may increase the risk of diabetes, cardiovascular disease and breast cancer. Long-term studies indicate that menopausal hormone therapy (MHT) reduces insulin resistance. To broaden knowledge of the mechanisms behind the influence of MHT on glucose homeostasis we focused on the direct short-term effects of MHT with oral combined estradiol and drospirenone on glucose and insulin metabolism in healthy postmenopausal women.

METHODS

This randomized, placebo-controlled study recruited 80 healthy postmenopausal women. Women were randomized to treatment with estradiol 1 mg continuously combined with drospirenone 2 mg or placebo for 6-8 weeks. All participants underwent an oral glucose tolerance test (OGTT) before and after the treatment period. Glucose, insulin, fructosamine and C-peptide levels were measured in serum before and 30, 60, 90, 120 and 150 min after a 75-gram oral glucose challenge.

RESULTS

After intervention, significantly higher glucose levels at 120 min (p < 0.024) and 150 min (p < 0.030) were observed in the MHT group compared with the placebo group. These glucose levels remained within the normal range. A significantly lower insulin peak serum level (p < 0.040) and a non-significantly smaller area under the curve (AUC) for insulin levels (p = 0.192) was observed in the MHT group at the end of the study period relative to baseline. No significant change in the insulin AUC in the placebo group was observed. There were no significant differences in fructosamine, HOMA-IR and C-peptide levels between the MHT group and the placebo group.

CONCLUSION

This double-blind randomized study (EC/2008/694) indicates that treating healthy, postmenopausal women with 1 mg estradiol continuously combined with 2 mg drospirenone significantly decreases peak insulin levels and increases peak glucose levels during an OGTT compared to placebo. These glucose levels remained within the normal range.

Association of menopause and type 2 diabetes mellitus

OBJECTIVE

Limited information is available on the direct effect of menopause and risk of type 2 diabetes mellitus (T2DM) among women with different metabolic types. We aimed to investigate whether menopause is a direct risk factor for T2DM.

METHODS

In this population-based cross-sectional study, women were recruited from a rural area of China from July to August 2013 and July to August 2014. Multivariate logistic regression analysis yielded adjusted odds ratios (ORs) and 95% CIs. Mediation analysis was performed to examine the contribution of age to menopause status-related T2DM.

RESULTS

We included 8,191 women (median age 56, interquartile range 47-65). The prevalence of T2DM was 13.22%. Risk of T2DM was increased with postmenopause versus premenopause status after adjustment (adjusted OR [aOR] = 1.90, 95% CI = 1.51-2.37), with the strongest association between postmenopause status and T2DM among women with body mass index (BMI) <24.0 kg/m (aOR, 3.25; 95% CI, 1.98-5.32). Risk of T2DM was increased with postmenopause status interacting with BMI, hypertension, triglycerides level, and waist circumference. On mediation analysis, age partially mediated the menopause status-T2DM association (indirect effect: OR = 1.27, 95% CI = 1.13-1.46; direct effect: OR = 1.88, 95% CI = 1.49-2.36).

CONCLUSIONS

The prevalence of T2DM is high among women, and postmenopause status might be a stable and significant risk factor for T2DM; especially, postmenopausal women with normal weight should not be ignored in addressing the risk.

Correlation between glucose metabolism and serum steroid hormones in patients with polycystic ovary syndrome

OBJECTIVE

Polycystic ovary syndrome (PCOS) is associated with an increased prevalence of dysglycaemia, which includes impaired glucose tolerance and type 2 diabetes mellitus (T2DM). Patients with PCOS demonstrate abnormal patterns of steroid hormones. Here, we analyse the correlation between glucose metabolism and serum steroid hormones in PCOS.

DESIGN

Observational double-centre study.

PATIENTS

914 patients with PCOS.

MEASUREMENTS

We assessed the glucose metabolism status of all patients according to the 1999 WHO criteria. Serum steroid hormones were measured by liquid chromatography-tandem mass spectrometry.

RESULTS

The median age of the patients was 26 years (interquartile range: 21-30), and 40.6% (371/914) had abnormal glucose metabolism: 29.3% (268/914) had prediabetes, and 11.3% (103/914) had T2DM. Correlation analysis not adjusting for confounding factors revealed that serum aldosterone, androstenedione, oestrone, pregnenolone and the free androgen index were positively correlated, while progesterone was negatively correlated with the risk of abnormal glucose metabolism. After adjusting for age, body mass index and fasting insulin levels in the logistic regression model, only aldosterone (P = .013), androstenedione (P = .046) and oestrone (P = .014; in quartiles) were correlated with the risk of abnormal glucose metabolism.

CONCLUSIONS

This study indicates a high prevalence of prediabetes and T2DM in patients with PCOS. Furthermore, there were positive correlations of serum aldosterone, androstenedione and oestrone with the risk of abnormal glucose metabolism after adjusting for confounding factors.

The role of estrogen in intervertebral disc degeneration

Intervertebral disc degeneration (IVDD) is a main contributor to low back and radicular pain, which imposes heavy economic burdens on society. However, the etiology and mechanism of IVDD are complex and still not completely clear. In particular, the role of estrogen in IVDD has not received much attention in recent research, although estrogen plays a crucial role in the metabolic dysfunction of others musculoskeletal structures, such as bone, muscle, and tendon. In this review, we attempt to describe the role of estrogen in IVDD and to summarize the proposed mechanisms in vivo and in vitro, as well as, to outline several interesting questions in this field.

Interaction between postmenopausal hormone therapy and diabetes on cataract

Supplemental Digital Content is available in the text

Objective:

We investigated whether postmenopausal hormone therapy (HT) use interacts with diabetes, a risk factor for several age-related eye diseases.

Methods:

A cross-sectional analysis of women involved in the Canadian Longitudinal Study on Aging was performed. The random sample comprised of 15,320 community-dwelling women between ages 45 and 85 years old sampled from areas adjacent to 11 data collection centers across Canada. Information on menopausal status and HT were collected by self-report. Data on diabetes and eye disease were obtained by self-report of a physician diagnosis. Multivariable logistic regression was used.

Results:

After adjusting for demographic, lifestyle, and health variables, a multiplicative interaction was identified such that HT use for 10 years or more was associated with a much higher odds of a report of cataract in women with type 2 diabetes (odds ratio = 2.44, 95% confidence interval 1.49, 3.99) but not in long-term HT users with no diabetes (odds ratio = 1.03, 95% confidence interval 0.87, 1.21) (interaction term P value = 0.013). HT use was not associated with glaucoma or macular degeneration.

Conclusions:

Long-term HT use and type 2 diabetes interact in their relationship with cataract. This novel finding should be confirmed. If confirmed, women with type 2 diabetes should be informed that long-term HT use increases their risk of cataract.

Supplemental Digital Content is available in the text

Video Summary:.

Type 2 Diabetes Mellitus and Menopausal Hormone Therapy: An Update

During menopausal transition, various phenotypical and metabolic changes occur, affecting body weight, adipose tissue distribution and energy expenditure as well as insulin secretion and sensitivity. Taken together, these can predispose women to the development of type 2 diabetes mellitus (T2DM). Many women in midlife experience climacteric symptoms, including hot flashes and night sweats. Menopausal hormone therapy (MHT) is then indicated. MHT has a favourable effect on glucose homeostasis in both women without and with T2DM. T2DM was considered in the past as a cardiovascular disease (CVD) equivalent, which would suggest that women with T2DM should not receive MHT. This notion may still deter many clinicians from prescribing MHT to these patients. However, nowadays there is strong evidence to support an individualised approach after careful evaluation of CVD risk. In older women with T2DM (> 60 years old or > 10 years in menopause), MHT should not be initiated, because it may destabilise mature atherosclerotic plaques, resulting in thrombotic episodes. In obese women with T2DM or in women with moderate CVD risk, transdermal 17β-oestradiol could be used. This route of delivery presents beneficial effects regarding triglyceride concentrations and coagulation factors. In peri- or recently post-menopausal diabetic women with low risk for CVD, oral oestrogens can be used, since they exhibit stronger beneficial effects on glucose and lipid profiles. In any case, a progestogen with neutral effects on glucose metabolism should be used, such as natural progesterone, dydrogesterone or transdermal norethisterone. The goal is to maximise benefits and minimise adverse effects.

Estradiol regulates daily rhythms underlying diet-induced obesity in female mice

The circadian system is a critical regulator of metabolism and obesity in males, but its role in regulating obesity in females is poorly understood. Because there are sex differences in the development of obesity and susceptibility to obesity-related disorders, we sought to determine the role of estrogens in regulating the circadian mechanisms underlying diet-induced obesity. When fed high-fat diet, C57BL/6J male mice gain weight, whereas females are resistant to diet-induced obesity. Here, we demonstrate that estradiol regulates circadian rhythms in females to confer resistance to diet-induced obesity. We found that ovariectomized females with undetectable circulating estrogens became obese and had disrupted daily rhythms of eating behavior and locomotor activity when fed a high-fat diet. The phase of the liver molecular circadian rhythm was also altered by high-fat diet feeding in ovariectomized mice. Estradiol replacement in ovariectomized females a fed high-fat diet rescued these behavioral and tissue rhythms. Additionally, restoring the daily rhythm of eating behavior in ovariectomized females with time-restricted feeding inhibited diet-induced obesity and insulin resistance. Together, these data suggest that the circadian system is a target for treating obesity and its comorbidities in women after menopause, when circulating levels of estrogens are too low to protect their circadian rhythms.

The developmental Wnt signaling pathway effector β-catenin/TCF mediates hepatic functions of the sex hormone estradiol in regulating lipid metabolism

The bipartite transcription factor β-catenin (β-cat)/T cell factor (TCF), formed by free β-cat and a given TCF family member, serves as the effector of the developmental Wnt signaling cascade. β-cat/TCFs also serve as effectors of certain peptide hormones or growth factors during adulthood. We reported that liver-specific expression of dominant-negative Transcription factor 7 like 2 (TCF7L2DN) led to impaired glucose disposal. Here we show that, in this LTCFDN transgenic mouse model, serum and hepatic lipid contents were elevated in male but not in female mice. In hepatocytes, TCF7L2DN adenovirus infection led to stimulated expression of genes that encode lipogenic transcription factors and lipogenic enzymes, while estradiol (E2) treatment attenuated the stimulation, associated with Wnt-target gene activation. Mechanistically, this E2-mediated activation can be attributed to elevated β-cat Ser675 phosphorylation and TCF expression. In wild-type female mice, ovariectomy (OVX) plus high-fat diet (HFD) challenge impaired glucose disposal and insulin tolerance, associated with increased hepatic lipogenic transcription factor sterol regulatory element-binding protein 1-c (SREBP-1c) expression. In wild-type mice with OVX, E2 reconstitution attenuated HFD-induced metabolic defects. Some of the attenuation effects, including insulin intolerance, elevated liver-weight gain, and hepatic SREBP-1c expression, were not affected by E2 reconstitution in HFD-fed LTCFDN mice with OVX. Finally, the effects of E2 in hepatocytes on β-cat/TCF activation can be attenuated by the G-protein-coupled estrogen receptor (GPER) antagonist G15. Our study thus expanded the scope of functions of the Wnt pathway effector β-cat/TCF, as it can also mediate hepatic functions of E2 during adulthood. This study also enriches our mechanistic understanding of gender differences in the risk and pathophysiology of metabolic diseases.

Conjugated Estrogens and Bazedoxifene Improve β Cell Function in Obese Menopausal Women

CONTEXT

Studies suggest that menopausal hormone therapy (MHT) prevents type 2 diabetes (T2D). The combination of conjugated estrogens (CE) with the selective estrogen receptor modulator bazedoxifene (BZA) is an MHT that improves obesity and T2D in preclinical models of menopausal metabolic syndrome. The effect of CE/BZA on adiposity and glucose homeostasis in obese postmenopausal women is unknown.

OBJECTIVE

To investigate the effect of CE/BZA on body composition, glucose homeostasis, and markers of inflammation in obese postmenopausal women.

RESEARCH DESIGN INTERVENTION AND PARTICIPANTS

Randomized, double-blind, placebo-controlled pilot trial of 12 obese menopausal women assigned to 12-week treatment with CE 0.45 mg/BZA 20 mg (n = 7) or placebo (n = 5). At baseline and after 12 weeks, we assessed body composition (dual-energy X-ray absorptiometry), glucose homeostasis (IV glucose tolerance test), and inflammation biomarkers.

RESULTS

Women treated with CE/BZA exhibited increased β cell function using homeostatic model assessment-B [median (interquartile range) CE/BZA vs placebo: 18.5 (-0.9 to 320.6) μU/mM vs -25.5 (-39.9 to -0.1) μU/mM; P = 0.045], and decreased basal glucose concentrations (Gb) [-5.2 (-9.2 to -1.7) mg/dL vs 2.7 (0.9 to 4.9) mg/dL; P = 0.029]. Insulin sensitivity was higher in the placebo arm [1.35 (1.12 to 1.82) (μU/mL) min-1 vs -0.24 (-1.50 to 0.19) (μU/mL) min-1; P = 0.029]. No changes between treatment groups were observed for the acute insulin response to glucose (AIRg), the disposition index (DI), body composition, and inflammatory biomarkers.

CONCLUSIONS

A 12-week treatment of obese postmenopausal women with CEs/BZA improves fasting β cell function and glucose concentrations without change in AIRg, HOMA-IR, DI, body composition, or markers of inflammation.

Family-based quantitative trait meta-analysis implicates rare noncoding variants in DENND1A in polycystic ovary syndrome

CONTEXT

Polycystic ovary syndrome (PCOS) is among the most common endocrine disorders of premenopausal women, affecting 5-15% of this population depending on the diagnostic criteria applied. It is characterized by hyperandrogenism, ovulatory dysfunction and polycystic ovarian morphology. PCOS is highly heritable, but only a small proportion of this heritability can be accounted for by the common genetic susceptibility variants identified to date.

OBJECTIVE

The objective of this study was to test whether rare genetic variants contribute to PCOS pathogenesis.Design, Patients, and Methods: We performed whole-genome sequencing on DNA from 261 individuals from 62 families with one or more daughters with PCOS. We tested for associations of rare variants with PCOS and its concomitant hormonal traits using a quantitative trait meta-analysis.

RESULTS

We found rare variants in DENND1A (P=5.31×10-5, Padj=0.039) that were significantly associated with reproductive and metabolic traits in PCOS families.

CONCLUSIONS

Common variants in DENND1A have previously been associated with PCOS diagnosis in genome-wide association studies. Subsequent studies indicated that DENND1A is an important regulator of human ovarian androgen biosynthesis. Our findings provide additional evidence that DENND1A plays a central role in PCOS and suggest that rare noncoding variants contribute to disease pathogenesis.

Sirt6 deletion in hepatocytes increases insulin sensitivity of female mice by enhancing ERα expression

Sirtuin 6 (Sirt6), a NAD⁺ -dependent protein deacetylase, is involved in hepatic glucose metabolism and insulin sensitivity, which impact metabolic homeostasis. In this paper, we discover that Sirt6 affects the insulin sensitivity of mice in a gender-dependent manner; few studies have been conducted on this issue. Based on reports revealing the influences of sex hormones on insulin signaling, this investigation explores the mechanism by which Sirt6 regulates the estrogen pathway and disrupts insulin signal transduction. Hepatocyte-specific Sirt6 knockout (Sirt6HKO) mice were generated to investigate the function of Sirt6 in hepatocytes. Mice were castrated or spayed to eliminate sex hormones. Insulin sensitivity was assessed via an insulin tolerance test (ITT) in vivo. The interaction of Sirt6 with the estrogen pathway and their impacts on insulin signal transduction were revealed by immunoblot and immunoprecipitation. Sirt6 deletion in hepatocytes significantly enhanced insulin sensitivity and signal transduction in female mice but not in male or spayed female mice as demonstrated by ITT and the phosphorylation level of Akt in the liver. We also identified upregulation of p300, ERα, and interaction of ERα with p85 in the liver of female Sirt6HKO mice. Additionally, Sirt6 was found to inhibit ERα protein stability in a p300-dependent manner without interacting directly with ERα. Our findings show that hepatic Sirt6 downregulates the ERα protein level in a p300-dependent manner and thus disturbs estrogen-induced improvement in insulin sensitivity in the liver, which may partially explain the gender difference in insulin sensitivity.

Impact of micronized progesterone on body weight, body mass index, and glucose metabolism: a systematic review

In women, body weight increases with age. Often menopausal hormone therapy (MHT) is blamed for enhancing this effect. In recent years, the debate on bioidentical MHT including micronized progesterone (MP) has increased. Among others, the question has been raised of whether MHT containing MP has an impact on body weight and glucose metabolism. Based on a systematic literature review on the impact of MHT containing MP on body weight, body mass index (BMI), and glucose metabolism, the following conclusions can be drawn: estrogens combined with MP (1) either do not change or reduce body weight in normal weight postmenopausal women, (2) do not change BMI in normal and overweight postmenopausal women, (3) do not change or improve fasting serum glucose levels in (non-)diabetic postmenopausal women, (4) do not change or improve fasting serum insulin levels in (non-)diabetic postmenopausal women, and (5) do not have an impact on serum glycated hemoglobin in postmenopausal diabetic women. This beneficial effect is probably mostly due to the estrogen MHT component.

Estrogen deficiency exacerbates Aβ-induced memory impairment through enhancement of neuroinflammation, amyloidogenesis and NF-ĸB activation in ovariectomized mice

Estrogen is well known to have a preventative effect in Alzheimer's disease (AD) pathology. Several studies have demonstrated that nuclear factor kappa-B (NF-ĸB) can contribute to the effects of estrogen on the development of AD. We investigated whether NF-ĸB affects amyloid-beta (Aβ)-induced memory impairment in an estrogen-lacking condition. In the present study, nine-week-old Institute cancer research (ICR) mice were ovariectomized to block estrogen stimulation. Ten weeks after the ovariectomization, mice were administered with Aβ (300 pmol) via intracerebroventricular (ICV) infusion for 2 weeks. Memory impairment, neuroinflammatory protein expression, and amyloidogenic pathways were then measured. Ovariectomized mice demonstrated severe memory impairment, Aβ accumulation, neprilysin downregulation, and activation of NF-ĸB signaling compared to sham-control mice. In vitro experiments demonstrated that β-estradiol (10 μM) inhibited Aβ (1 μM)-induced neuroinflammation in microglial BV-2 cells and prevented Aβ-induced cell death in primary cultured neuronal cells. As in in vivo experiments, NF-ĸB activation was significantly upregulated in in vitro experiments. Furthermore β-estradiol treatment inhibited NF-ĸB activation in both of microglial BV-2 cells and cultured neuronal cells. These findings suggest that estrogen may protect against memory impairment through the regulation of Aβ accumulation and neurogenic inflammation by inhibiting NF-κB activity.

Estrogens Promote Misfolded Proinsulin Degradation to Protect Insulin Production and Delay Diabetes

Conjugated estrogens (CE) delay the onset of type 2 diabetes (T2D) in postmenopausal women, but the mechanism is unclear. In T2D, the endoplasmic reticulum (ER) fails to promote proinsulin folding and, in failing to do so, promotes ER stress and β cell dysfunction. We show that CE prevent insulin-deficient diabetes in male and in female Akita mice using a model of misfolded proinsulin. CE stabilize the ER-associated protein degradation (ERAD) system and promote misfolded proinsulin proteasomal degradation. This involves activation of nuclear and membrane estrogen receptor-α (ERα), promoting transcriptional repression and proteasomal degradation of the ubiquitin-conjugating enzyme and ERAD degrader, UBC6e. The selective ERα modulator bazedoxifene mimics CE protection of β cells in females but not in males.

Menstrual Dysfunction in Girls From the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) Study

CONTEXT

Little is known about reproductive function in girls with youth-onset type 2 diabetes.

OBJECTIVES

To characterize girls with irregular menses and effects of glycemic treatments on menses and sex steroids in the Treatment Options for Type 2 Diabetes in Youth (TODAY) study.

DESIGN

Differences in demographic, metabolic, and hormonal characteristics between regular- vs irregular-menses groups were tested; treatment group (metformin with or without rosiglitazone, metformin plus lifestyle) effect on menses and sex steroids over time in the study was assessed. This is a secondary analysis of TODAY data.

SETTING

Multicenter study in an academic setting.

PATIENTS

TODAY girls not receiving hormonal contraception and those at least 1-year postmenarche were included. Irregular menses was defined as three or fewer periods in the prior 6 months.

RESULTS

Of eligible participants with serum measurement of sex steroids (n = 190; mean age, 14 years), 21% had irregular menses. Those with irregular vs regular menses had higher body mass index (BMI) (P = 0.001), aspartate aminotransferase (AST) (P = 0.001), free androgen index (P = 0.0003), and total testosterone (P = 0.01) and lower sex hormone-binding globulin (SHBG) (P = 0.004) and estradiol (P = 0.01). Differences remained after adjustment for BMI. There was no treatment group effect on menses or sex steroids at 12 or 24 months, and no association of sex steroids was seen with measures of insulin sensitivity or secretion.

CONCLUSIONS

Menstrual dysfunction is common in girls with recently diagnosed type 2 diabetes and associated with alterations in sex steroids, SHBG, and AST but not with alteration in insulin sensitivity or β-cell function and did not improve with 2 years of antihyperglycemic treatment.

Gender difference in NASH susceptibility: Roles of hepatocyte Ikkβ and Sult1e1

Myeloid cell and hepatocyte IKKβ may mediate the genesis of obesity and insulin resistance in mice fed high fat diet. However, their gender-specific roles in the pathogenesis of non-alcoholic steatohepatitis (NASH) are not known. Here we demonstrate myeloid IKKβ deficiency prevents Western diet-induced obesity and visceral adiposity in females but not in males, and attenuates hyperglycemia, global IR, and NASH in both genders. In contrast, all metabolic sequela including NASH are aggravated by hepatocyte IKKβ deficiency (IkbkbΔhep) in male but not female mice. Gene profiling identifies sulfotransferase family 1E (Sult1e1), which encodes a sulfotransferase E1 responsible for inactivation of estrogen, as a gene upregulated in NASH in both genders and most conspicuously in male IkbkbΔhep mice having worst NASH and lowest plasma estradiol levels. LXRα is enriched to LXRE on Sult1e1 promoter in male WT and IkbkbΔhep mice with NASH, and a Sult1e1 promoter activity is increased by LXRα and its ligand and augmented by expression of a S32A mutant of IκBα. These results demonstrate striking gender differences in regulation by IKKβ of high cholesterol saturated fat diet-induced metabolic changes including NASH and suggest hepatocyte IKKβ is protective in male due at least in part to its ability to repress LXR-induced Sult1e1. Our findings also raise a caution for systemic IKK inhibition for the treatment of NASH as it may exacerbate the disease in male patients.

Effect of Half-dose and Standard-dose Conjugated Equine Estrogens Combined with Natural Progesterone or Dydrogesterone on Components of Metabolic Syndrome in Healthy Postmenopausal Women: A Randomized Controlled Trial

Background:

Menopausal hormone therapy (MHT) has been proven to have beneficial effects on several components of metabolic syndrome. However, the effects vary according to different regimens, dosages, and duration of MHT. The aim of the study was to evaluate the effect of standard-dose 0.625 mg conjugated equine estrogen (CEE) and half-dose 0.3 mg CEE daily with different progestogens in a continuous sequential regimen on postmenopausal metabolic parameters in generally healthy postmenopausal women.

Methods:

A prospective, open-label, randomized controlled clinical trial was conducted between February 2014 and December 2015. Totally 123 Chinese postmenopausal women with climacteric symptoms were included in this study and were randomly assigned to three groups: Group A received CEE 0.3 mg/micronized progesterone (MP) 100 mg daily; Group B received CEE 0.625 mg/MP 100 mg daily; and Group C received CEE 0.625 mg/dydrogesterone 10 mg daily. Drugs were given in a continuous sequential pattern. The duration of treatment was 12 months. Clinical, anthropometrical, and metabolic variables were measured. Data were analyzed according to intention-to-treat analysis, using Student's t-test and analysis of variance.

Results:

A total of 107 participants completed the 12-month follow-up and were included in the data analysis. At 12 months of treatment, high-density lipoprotein cholesterol and apolipoprotein A significantly increased, and low-density lipoprotein cholesterol, fasting glucose, and glycosylated hemoglobin significantly decreased in Groups B and C, compared with baseline (all P < 0.05). Among the three groups, only Group C showed significantly increased triglycerides compared with baseline (1.61 ± 0.80 mmol/L vs. 1.21 ± 0.52 mmol/L, P = 0.026). Each group showed a neutral effect on total cholesterol, lipoprotein A, apolipoprotein B, and fasting insulin levels. No cardiovascular and venous thromboembolic events occurred in the three groups.

Conclusions:

Among Chinese postmenopausal women, half-dose CEE was not sufficient to induce a favorable lipid and carbohydrate profile compared with standard-dose CEE. Adding natural MP may counterbalance the TG-increasing effect of CEE.

Trial Registration:

ClinicalTrials.gov, NCT01698164; https://clinicaltrials.gov/ct2/show/NCT01698164?term=NCT01698164&rank=1.

Menopausal Hormone Therapy and Type 2 Diabetes Prevention: Evidence, Mechanisms, and Clinical Implications

Type 2 diabetes has reached epidemic proportions in the United States. Large, randomized controlled trials suggest that menopausal hormone therapy (MHT) delays the onset of type 2 diabetes in women. However, the mechanisms and clinical implications of this association are still a matter of controversy. This review provides an up-to-date analysis and integration of epidemiological, clinical, and basic studies, and proposes a mechanistic explanation for the effect of menopause and MHT on type 2 diabetes development and prevention. We discuss the beneficial effects of endogenous estradiol with respect to insulin secretion, insulin sensitivity, and glucose effectiveness; we also discuss energy expenditure and adipose distribution, both of which are affected by menopause and improved by MHT, which thereby decreases the incidence of type 2 diabetes. We reconcile differences among studies that investigated the effect of menopause and MHT formulations on type 2 diabetes. We argue that discrepancies arise from physiological differences in methods used to assess glucose homeostasis, ranging from clinical indices of insulin sensitivity to steady-state methods to assess insulin action. We also discuss the influence of the route of estrogen administration and the addition of progestogens. We conclude that, although MHT is neither approved nor appropriate for the prevention of type 2 diabetes due to its complex balance of risks and benefits, it should not be withheld from women with increased risk of type 2 diabetes who seek treatment for menopausal symptoms.

Associations of Steroid Sex Hormones and Sex Hormone-Binding Globulin With the Risk of Type 2 Diabetes in Women: A Population-Based Cohort Study and Meta-analysis

It remains unclear whether endogenous sex hormones (ESH) are associated with risk of type 2 diabetes (T2D) in women. Data of 3,117 postmenopausal women participants of the Rotterdam Study were analyzed to examine whether ESH and sex hormone-binding globulin (SHBG) were associated with the risk of incident T2D. Additionally, we performed a systematic review and meta-analysis of studies assessing the prospective association of ESH and SHBG with T2D in women. During a median follow-up of 11.1 years, we identified 384 incident cases of T2D in the Rotterdam Study. No association was observed between total testosterone (TT) or bioavailable testosterone (BT) with T2D. SHBG was inversely associated with the risk of T2D, whereas total estradiol (TE) was associated with increased risk of T2D. Similarly, in the meta-analysis of 13 population-based prospective studies involving more than 1,912 incident T2D cases, low levels of SHBG and high levels of TE were associated with increased risk of T2D, whereas no associations were found for other hormones. The association of SHBG with T2D did not change by menopause status, whereas the associations of ESH and T2D were based only in postmenopausal women. SHBG and TE are independent risk factors for the development of T2D in women.

Menopause, hormone therapy and diabetes

Over the past three decades, the prevalence of diabetes has increased four-fold. Coupled with the global obesity epidemic and aging of the world's population, a perfect metabolic storm is brewing. The influence of menopause and exogenous estrogen and progestogens must be included in this equation. In this review, criteria for diagnosing diabetes and recommendations for screening are described. The reported effects of menopause on diabetes risk in healthy women are reviewed as well as the relationship between established diabetes and the timing of menopause. The effects of menopausal hormone therapies (MHT) on glucose control in women with diabetes and the effect of MHT on diabetes risk in menopausal women without diabetes are described. Evidence-based strategies to prevent diabetes in midlife women are highlighted. The augmenting effect of diabetes on chronic health concerns of aging women, such as cardiovascular disease, osteoporosis, and cancer, along with current recommendations for screening and prevention are presented. Given the current demographics of today's world, the content of this review may apply to as many as one-third of the average practitioner's postmenopausal patient population.

Reproductive history and risk of type 2 diabetes mellitus in postmenopausal women: findings from the Women's Health Initiative

OBJECTIVE

The aim of the study was to understand the association between women's reproductive history and their risk of developing type 2 diabetes. We hypothesized that characteristics signifying lower cumulative endogenous estrogen exposure would be associated with increased risk.

METHODS

Prospective cohort analysis of 124,379 postmenopausal women aged 50 to 79 years from the Women's Health Initiative (WHI). We determined age of menarche and final menstrual period, and history of irregular menses from questionnaires at baseline, and calculated reproductive length from age of menarche and final menstrual period. Presence of new onset type 2 diabetes was from self-report. Using multivariable Cox proportional hazards models, we assessed associations between reproductive variables and incidence of type 2 diabetes.

RESULTS

In age-adjusted models, women with the shortest (<30 y) reproductive periods had a 37% (95% CI, 30-45) greater risk of developing type 2 diabetes than women with medium-length reproductive periods (36-40 y). Women with the longest (45+ y) reproductive periods had a 23% (95% CI, 12-37) higher risk than women with medium-length periods. These associations were attenuated after full adjustment (HR 1.07 [1.01, 1.14] for shortest and HR 1.09 [0.99, 1.22] for longest, compared with medium duration). Those with a final menstrual period before age 45 and after age 55 had an increased risk of diabetes (HR 1.04; 95% CI, 0.99-1.09 and HR 1.08; 95% CI, 1.01-1.14, respectively) compared to those with age of final menstrual period between 46 and 55 years. Timing of menarche and cycle regularity was not associated with risk after full adjustment.

CONCLUSIONS

Reproductive history may be associated with type 2 diabetes risk. Women with shorter and longer reproductive periods may benefit from lifestyle counseling to prevent type 2 diabetes.

Role of Estrogens in the Regulation of Liver Lipid Metabolism

Before menopause, women are protected from atherosclerotic heart disease associated with obesity relative to men. Sex hormones have been proposed as a mechanism that differentiates this risk. In this review, we discuss the literature around how the endogenous sex hormones and hormone treatment approaches after menopause regulate fatty acid, triglyceride, and cholesterol metabolism to influence cardiovascular risk.The important regulatory functions of estrogen signaling pathways with regard to lipid metabolism have been in part obscured by clinical trials with hormone treatment of women after menopause, due to different formulations, routes of delivery, and pairings with progestins. Oral hormone treatment with several estrogen preparations increases VLDL triglyceride production. Progestins oppose this effect by stimulating VLDL clearance in both humans and animals. Transdermal estradiol preparations do not increase VLDL production or serum triglycerides.Many aspects of sex differences in atherosclerotic heart disease risk are influenced by the distributed actions of estrogens in the muscle, adipose, and liver. In humans, 17β-estradiol (E2) is the predominant circulating estrogen and signals through estrogen receptor alpha (ERα), estrogen receptor beta (ERβ), and G-protein-coupled estrogen receptor (GPER). Over 1000 human liver genes display a sex bias in their expression, and the top biological pathways are in lipid metabolism and genes related to cardiovascular disease. Many of these genes display variation depending on estrus cycling in the mouse. Future directions will likely rely on targeting estrogens to specific tissues or specific aspects of the signaling pathways in order to recapitulate the protective physiology of premenopause therapeutically after menopause.

The Metabolic Syndrome in Women

The clustering of metabolic risk factors, overweight and hypertension is of particular importance in postmenopausal women due to the negative effect of menopause on bodyweight, glucose metabolism and the development of hypertension. Menopause acts directly as a risk factor by reducing the direct beneficial effect of ovarian hormones on cardiovascular functions, and indirectly by negatively influencing traditional risk factors for coronary artery disease. All changes occurring after the menopause must be regarded under a unifying mechanism that induces unfavorable changes in cardiovascular risk factors and vascular functions, which interact with each other, amplifying the effect of ovarian hormone deficiency and aging.

Diabetes and Menopause

During menopause, women's body composition, sex hormone profile, and metabolic profile may change dramatically. In this review, we summarize studies examining whether the menopausal transition and physiologic factors characterizing the transition are associated with increased risk of diabetes. We review the evidence for estrogen therapy and diabetes risk and studies examining the relationship between diabetes and menarche, which represents an extension of the reproductive life span at the opposite end of the age spectrum. Although studied less extensively, the presence of type 1 or type 2 diabetes may increase the risk of ovarian failure, and we review this literature. In conclusion, we note that the evidence linking menopausal sex hormone changes with increased diabetes risk is weak, although rapid changes as observed with oophorectomy may increase risk. Further studies should investigate the contradictory effects of estrogen therapy upon hepatic and glucose metabolism in mid-life women.