Increased visceral fat and decreased energy expenditure during the menopausal transition

Greater short-term weight loss in women 20-45 versus 55-65 years of age following bariatric surgery

BACKGROUND

Whether and how sex and age affect bariatric-surgery outcome is poorly understood. Estrogens regulate body composition in women and animals, and increase weight loss in a rodent model of gastric bypass, suggesting that premenopausal women may lose more weight following bariatric surgery.

METHODS

One thousand three hundred fifty-six female gastric-bypass or gastric-banding patients were retrospectively grouped as 20-45 years old (presumptively premenopausal; n = 1,199) and 55-65 years old (presumptively postmenopausal; n = 157). Mixed-model ANCOVA followed by Bonferroni-corrected t tests were used to categorically test the effect of age on percent excess body weight loss (%EBWL) at 1 and 2 years post-surgery, controlling for preoperative EBW and surgery type. Age effects were also tested dimensionally in all women and in 289 male patients.

RESULTS

Twenty- to forty-five-year-old women showed greater %EBWL 1 and 2 years post-surgery than 55-65-year-old women (p's < 0.0005). No age effect was detected in 20-25- vs. 30-35-, 30-35- vs. 40-45-, or 20-25- vs. 40-45-year-old women (p's > 0.2) This age effect was detected only after gastric banding, with 20-45-year-old women losing ∼7 kg more than 55-65-year-old women after 2 years. Dimensional analysis confirmed a significant inverse effect of age on bariatric surgery outcome in women, but did not detect any effect in men.

CONCLUSIONS

Results indicate that 55-65-year-old women lose less weight than 20-45-year-old women in the initial 2 years after bariatric surgery, especially gastric banding; this may be mediated by age- or menopause-associated changes in physical activity, energy expenditure, or energy intake.

Pediatric non-alcoholic fatty liver disease: New insights and future directions

One of the most common complications of childhood obesity is the non-alcoholic fatty liver disease (NAFLD), which is the most common form of liver disease in children. NAFLD is defined by hepatic fat infiltration > 5% hepatocytes, as assessed by liver biopsy, in the absence of excessive alcohol intake, viral, autoimmune and drug-induced liver disease. It encompasses a wide spectrum of liver diseases ranging from simple steatosis to non-alcoholic steatohepatitis, which, in turn, can evolve into cirrhosis and end stage liver disease. Obesity and insulin resistance are the main risk factors for pediatric NAFLD. In fact, NAFLD is strongly associated with the clinical features of insulin resistance especially the metabolic syndrome, prediabetes and type 2 diabetes mellitus (T2D). In particular, it has been clearly shown in obese youth that the prevalence of metabolic syndrome, pre-diabetes and type 2 diabetes increases with NAFLD severity progression. Evidence that not all of the obese patients develop NAFLD suggests that the disease progression is likely to depend on complex interplay between environmental factors and genetic predisposition. Recently, a non-synonymous SNP (rs738409), characterized by a C to G substitution encoding an isoleucine to methionine substitution at the amino acid position 148 in the patatin like phospholipase containing domain 3 gene (PNPLA3), has been associated with hepatic steatosis in a multiethnic cohort of adults as well as in children. Another important polymorphisms that acts with PNPLA3 to convey susceptibility to fatty liver in obese youths is the rs1260326 polymorphism in the glucokinase regulatory protein. The pharmacological approach in NAFLD children poorly adherent to or being unresponsive/partially responsive to lifestyle changes, is aimed at acting upon specific targets involved in the pathogenesis. There are some therapeutic approaches that are being studied in children. This article reviews the current knowledge regarding the pediatric fatty liver disease, the new insights and the future directions.

Estrogen or raloxifene during postmenopausal weight loss: adiposity and cardiometabolic outcomes

OBJECTIVE

Estrogen-based hormone therapy (HT) attenuates abdominal fat gain after menopause, but whether HT improves abdominal fat loss during weight loss is unknown. It was hypothesized that HT or a selective estrogen receptor modulator (raloxifene) would augment reductions in abdominal visceral fat during weight loss when compared to placebo, potentially increasing improvements in glucose tolerance and lipid profile.

METHODS

Healthy postmenopausal women (n = 119; age 50-70 yr) underwent a 6-month weight-loss (primarily exercise) intervention with randomization to raloxifene (60 mg/d), HT (conjugated estrogens, 0.625 mg/d), or placebo. Outcomes were change in total and abdominal (visceral and subcutaneous) fat mass, lipid profile, and fasting and post-challenge glucose and insulin.

RESULTS

Neither HT nor raloxifene augmented loss of total or abdominal fat mass during exercise-induced weight loss when compared with placebo. Weight loss-induced improvements in risk factors were similar among the three groups, except for a greater reduction in fasted glucose in the HT group (difference in change [95%CI] from placebo; -0.40 [-0.76, -0.05]) and greater reductions in LDL (-0.36 [-0.63, -0.09]) and increases in HDL (0.15 [0.07, 0.24]) in both treatment groups.

CONCLUSIONS

Postmenopausal HT and raloxifene did not increase abdominal fat loss during weight loss, but did improve some cardiometabolic outcomes.

Gender and menopause impact severity of fibrosis among patients with nonalcoholic steatohepatitis

Estrogens inhibit stellate cell activation and fibrogenesis. Thus, gender and reproductive states may influence the degree of fibrosis in patients with nonalcoholic steatohepatitis (NASH). To investigate the association between gender, menopause, and the severity of liver fibrosis in patients with NASH, we analyzed 541 adult patients enrolled from our Duke Liver Clinics (n = 338) and the Duke Metabolic and Weight Loss Surgery Program (n = 203) who had a histologic diagnosis of NASH. Multiple ordinal logistic regression models were used to assess the association between gender, menopause, and severity of liver fibrosis. Overall, men, premenopausal, and postmenopausal women composed 35.1%, 28.4%, and 36.5% of the population, respectively. The mean age was 48 years and 22% had advanced fibrosis. After adjusting for covariates (enrolling site, grades of portal inflammation, and hepatocyte ballooning) and potential confounders (race, body mass index, diabetes/prediabetes, hypertension), adjusted cumulative odd ratio (ACOR) and 95% confidence interval (CI) for greater fibrosis severity was 1.4 (0.9, 2.1) (P = 0.17) for postmenopausal women and 1.6 (1.0, 2.5) (P = 0.03) for men, having premenopausal women as a reference. There was borderline interaction between gender and age group divided by age 50, the average age at menopause in the U.S. (P = 0.08): ACOR and 95% CI of having greater fibrosis severity in men compared to women was 1.8 (1.1, 2.9) for patients with age <50 years (P = 0.02) and 1.2 (0.7, 2.1) for patients with age ≥50 years (P = 0.59).

CONCLUSION

Men are at a higher risk of having more severe fibrosis compared to women before menopause, while postmenopausal women have a similar severity of liver fibrosis compared to men. These findings may be explained by the protective effects of estrogen against fibrogenesis.

Determinants of sedentary 24-h energy expenditure: equations for energy prescription and adjustment in a respiratory chamber

BACKGROUND

Achieving energy balance is critical for the interpretation of results obtained in respiratory chambers. However, 24-h energy expenditure (24EE) predictions based on estimated resting metabolic rate and physical activity level are often inaccurate and imprecise.

OBJECTIVE

We aimed to develop and validate equations to better achieve energy balance in a respiratory chamber by adding or subtracting food items.

DESIGN

By using a randomized data set with measures of 24EE (n = 241) performed at the Pennington Biomedical Research Center, we developed equations to predict 24EE from anthropometric, demographic, and body composition variables before and at 3 and 7 h into the chamber measurement. The equations were tested on an independent data set (n = 240) and compared with published predictive equations.

RESULTS

By using anthropometric and demographic variables, the equation was as follows: 24EE (kcal/d) = 11.6 [weight (kg)] + 8.03 [height (cm)] - 3.45 [age (y)] + 217 (male) - 52 (African American) - 235. The mean prediction error was -9 ± 155 kcal/d (2046 ± 305 compared with 2055 ± 343 kcal/d for measured 24EE; P = 0.36). The prediction achieved a precision of ±10% of measured 24EE in 83% of the participants. Energy prescription was then refined by equations with the use of energy expenditure values after 3 h, 7 h, or both into the chamber study. These later equations improved the precision (±10% of measured 24EE) to 92% (P = 0.003) and 96% (P < 0.0001) of the participants at 3 and 7 h, respectively. Body composition did not improve 24EE predictions.

CONCLUSIONS

We showed the use of a set of equations to prescribe and adjust energy intake to achieve energy balance in respiratory chambers over 24 h. These equations may be used in most respiratory chambers and modified to accommodate exercise or specific feeding protocols.

Age-related differences in abdominal fat distribution in premenopausal and postmenopausal women with cardiovascular disease

OBJECTIVE

The aim of this study was to determine the effect of sex and the menopausal transition on age-related differences in visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) among patients with cardiovascular disease.

METHODS

A cross-sectional study of 997 women and 3,409 men with cardiovascular disease was performed. VAT and SAT were measured by ultrasonography. Differences in abdominal fat per decade in premenopausal and postmenopausal women were analyzed with linear regression and compared with men younger and older than the mean menopause age of women.

RESULTS

VAT increased gradually across advancing age groups. For postmenopausal women, the 10-year differences in VAT were smaller than those for premenopausal women (0.24 cm [β = 0.24; 95% CI, 0.05 to 0.43] vs 0.71 cm [β = 0.71; 95% CI, 0.29 to 1.12]). There were no differences in SAT (β = -0.12; 95% CI, -0.37 to 0.13) in premenopausal women, and SAT decreased across the age groups of postmenopausal women (-0.36 cm per decade [β = -0.36; 95% CI, -0.47 to -0.26]). Postmenopausal women showed 10-year differences in VAT that were larger than those for men 48 years or older (0.24 cm per decade [β = 0.24; 95% CI, 0.05 to 0.43] vs -0.01 cm per decade [β = -0.01; 95% CI, -0.12 to 0.10]). In addition, 10-year differences in SAT were larger in postmenopausal women than in men 48 years or older (-0.36 cm [β = -0.36; 95% CI, -0.47 to -0.26] vs -0.22 cm [β = -0.22; 95% CI, -0.27 to -0.18]).

CONCLUSIONS

Menopause is not associated with accelerated fat gain in women with cardiovascular disease. Compared with similar-aged men, postmenopausal women show a steeper increase in VAT and a steeper decrease in SAT. These ongoing changes might add to an unfavorable metabolic profile associated with an increased risk of recurrent cardiovascular events.

Aldehyde dehydrogenase 1A1: friend or foe to female metabolism?

In this review, we summarize recent advances in understanding vitamin A-dependent regulation of sex-specific differences in metabolic diseases, inflammation, and certain cancers. We focus on the characterization of the aldehyde dehydrogenase-1 family of enzymes (ALDH1A1, ALDH1A2, ALDH1A3) that catalyze conversion of retinaldehyde to retinoic acid. Additionally, we propose a “horizontal transfer of signaling” from estrogen to retinoids through the action of ALDH1A1. Although estrogen does not directly influence expression of Aldh1a1, it has the ability to suppress Aldh1a2 and Aldh1a3, thereby establishing a female-specific mechanism for retinoic acid generation in target tissues. ALDH1A1 regulates adipogenesis, abdominal fat formation, glucose tolerance, and suppression of thermogenesis in adipocytes; in B cells, ALDH1A1 plays a protective role by inducing oncogene suppressors Rara and Pparg. Considering the conflicting responses of Aldh1a1 in a multitude of physiological processes, only tissue-specific regulation of Aldh1a1 can result in therapeutic effects. We have shown through successful implantation of tissue-specific Aldh1a1^−/− preadipocytes that thermogenesis can be induced in wild-type adipose tissues to resolve diet-induced visceral obesity in females. We will briefly discuss the emerging role of ALDH1A1 in multiple myeloma, the regulation of reproduction, and immune responses, and conclude by discussing the role of ALDH1A1 in future therapeutic applications.

Lower resting and total energy expenditure in postmenopausal compared with premenopausal women matched for abdominal obesity

The menopause is accompanied by increased risk of obesity, altered body fat distribution and decreased skeletal muscle mass. The resulting decrease in RMR should be accompanied by a compensatory change in energy balance to avoid weight gain. We aimed to investigate habitual energy intake and expenditure in pre- and postmenopausal women matched for abdominal obesity. We recruited fifty-one healthy Caucasian women, BMI > 18·5 and <35 kg/m(2), aged 35-45 years (premenopausal, n 26) and 55-65 years (postmenopausal, n 25). Energy intake was measured using 3 d diet diaries and dietary fat quality assessed using adipose tissue fatty acid biomarkers. RMR was measured using indirect calorimetry, and total energy expenditure (TEE) and activity energy expenditure using a combined accelerometer and heart rate monitor. Postmenopausal women had lower RMR and TEE and spent significantly less time undertaking moderate exercise than premenopausal women. Postmenopausal women had a tendency for a lower energy intake, and a similar macronutrient intake but a significantly lower adipose tissue n-6:n-3 ratio (24·6 (se 1·6) v. 37·7 (se 3·1); P < 0·001). The main lifestyle determinant of bone mineral density (which was significantly lower in postmenopausal women) was TEE for premenopausal women, and dietary n-6:n-3 ratio for postmenopausal women. The present results suggest that weight maintenance is achieved in the post- compared with premenopausal status through a combination of reduced energy intake and reduced TEE in a regimen that compromises micronutrient intake and has a negative impact on lean tissue mass. However, lower n-6:n-3 fatty acid intake in postmenopausal women is associated with greater bone mineral density.

Effects of preventive acupuncture and moxibustion on fat accumulation, blood lipid, and uterus e 2 of menopause rats

Objective. To observe the effect of preventive acupuncture and moxibustion on blood lipid of menopause rats. Methods. Seventy 10-month-old SD rats with estrous cycle disorders were divided into three control groups and four treatment groups (n = 10/group) and another ten 3.5-month-old female SD rats were chosen as young control group. Preventive acupuncture and moxibustion were applied at Guanyuan (CV 4). Body weight growth rate has been recorded. Plasma total cholesterol (TC), triglyceride (TG), low density lipoprotein (LDL), and high density lipoprotein (HDL) levels and uterus E 2 level were measured. Results. Compared to young control group, plasma TC and LDL increased and uterus E 2 reduced significantly in 12-month-old control group. Compared to 12-month-old control group, plasma TC and LDL level and body weight growth rate decreased while HDL level increased remarkably in preventive acupuncture 12-month-old group. Compared to 14-month-old control group, plasma TC level and body weight growth rate decreased remarkably in preventive moxibustion 14-month-old group. Conclusions. Preventive acupuncture and moxibustion can significantly decrease the plasma TG and LDL, increase the plasma HDL, and prevent fat accumulation. Our finding suggests that preventive acupuncture and moxibustion have beneficial effects on blood lipid. Different treatment effects were found between preventive acupuncture and preventive moxibustion.

Employment status, depressive symptoms, and waist circumference change in midlife women: the Study of Women's Health Across the Nation (SWAN)

PURPOSE

Changes in employment status have shown inconsistent associations with adiposity. This study tested whether the presence of elevated depressive symptoms explains variability in the time-varying association between employment status and central adiposity.

METHOD

Employment status, depressive symptoms, and waist circumference (WC) were assessed annually over 10 years in a multiethnic sample of 3220 midlife women enrolled in the Study of Women's Health Across the Nation. Linear mixed-effects models tested time-varying associations of employment status, depressive symptoms, and their interaction with WC.

RESULTS

WC increases were greatest during the years of combined nonemployment and elevated depressive symptoms (1.00 cm/y) and lowest in the years of full-time employment and elevated depressive symptoms (0.25 cm/y), compared with the years of full-time employment and nonelevated depressive symptoms (0.51 cm/y). Employment status was unrelated to WC in years without elevated depressive symptoms. The pattern of results was unchanged when analyses were restricted to preretirement observations and did not vary according to WC at baseline or ethnicity/race.

CONCLUSIONS

Identifying and managing depressive symptoms in midlife women who are not working may help prevent increases in central adiposity.

To exercise, or, not to exercise, during menopause and beyond

Menopausal symptoms in women can be severe and disruptive to overall quality of life. Hormone replacement therapy, is known to be effective in ameliorating symptoms, however, reporting of side effects has resulted in alternative treatment options. Exercise has been assessed as an alternative treatment option for alleviating menopausal symptoms, including, psychological, vasomotor, somatic and sexual symptoms. Here we report the effects of physical activity and exercise on menopause symptoms in menopausal women.

BRCA1/2 mutation carriers are potentially at higher cardiovascular risk

BRCA1/2 mutation carriers have an elevated risk of developing breast and ovarian cancer at a relatively young age. Risk-reducing salpingo-oophorectomy is an established strategy to tremendously reduce the risk of ovarian cancer. It is recommended to perform this surgery at age 35-40 years (BRCA1) and at age 40-45 years (BRCA2) resulting in an early and abrupt menopause. BRCA1/2 mutation carriers are potentially at higher risk of cardiovascular diseases due to early surgical menopause, and cardiotoxic effects of adjuvant treatment for breast cancer. Furthermore, preliminary results of experimental studies suggest a possible causative function of the BRCA genes in cardiovascular risk. More research on cardiovascular health risks in BRCA1/2 mutation carriers is needed, especially in the field of cardio-oncology, requiring additional attention to potentially cumulative effects on cardiovascular risks in this specific group of women.

Role of estrogen on skeletal muscle mitochondrial function in ovariectomized rats: a time course study in different fiber types

Postmenopausal women are prone to develop obesity and insulin resistance, which might be related to skeletal muscle mitochondrial dysfunction. In a rat model of ovariectomy (OVX), skeletal muscle mitochondrial function was examined at short- and long-term periods after castration. Mitochondrial parameters in the soleus and white gastrocnemius muscle fibers were analyzed. Three weeks after surgery, there were no differences in coupled mitochondrial respiration (ATP synthesis) with pyruvate, malate, and succinate; proton leak respiration; or mitochondrial reactive oxygen species production. However, after 3 wk of OVX, the soleus and white gastrocnemius muscles of the OVX animals showed a lower use of palmitoyl-carnitine and glycerol-phosphate substrates, respectively, and decreased peroxisome proliferator-activated receptor-γ coactivator-1α expression. Estrogen replacement reverted all of these phenotypes. Eight weeks after OVX, ATP synthesis was lower in the soleus and white gastrocnemius muscles of the OVX animals than in the sham-operated and estrogen-treated animals; however, when normalized by citrate synthase activity, these differences disappeared, indicating a lower muscle mitochondria content. No differences were observed in the proton leak parameter. Mitochondrial alterations did not impair the treadmill exercise capacity of the OVX animals. However, blood lactate levels in the OVX animals were higher after the physical test, indicating a compensatory extramitochondrial ATP synthesis system, but this phenotype was reverted by estrogen replacement. These results suggest early mitochondrial dysfunction related to lipid substrate use, which could be associated with the development of the overweight phenotype of ovariectomized animals.

The cut-off values of anthropometric indices for identifying subjects at risk for metabolic syndrome in Iranian elderly men

AIM

This study aimed to investigate which anthropometric indices could be a better predictor of metabolic syndrome (MetS) and the cut-off points for these surrogates to appropriately differentiate MetS in the Iranian elderly.

METHOD

The present cross-sectional study was conducted on a sample of Isfahan Healthy Heart Program (IHHP). MetS was defined according to Third Adult Treatment Panel (ATPIII). In total, 206 elderly subjects with MetS criteria were selected. Anthropometric indices were measured and plotted using receiver operating characteristic (ROC) curves.

RESULTS

WC followed by WHtR yielded the highest area under the curve (AUC) (0.683; 95% CI 0.606-0.761 and 0.680; 95% CI 0.602-0.758, resp.) for MetS. WC at a cut of 94.5 cm resulted in the highest Youden index with sensitivity 64% and 68% specificity to predict the presence of ≥2 metabolic risk factors. BMI had the lowest sensitivity and specificity for MetS and MetS components. WC has the best ability to detect MetS which followed by WHtR and BMI had a lower discriminating value comparatively.

CONCLUSION

WC is the best predictor for predicting the presence of ≥2 metabolic risk factors among Iranian elderly population and the best value of WC is 94.5 cm. This cut-off values of WC should be advocated and used in Iranian men until larger cross-sectional studies show different results.

Lifestyle interventions targeting body weight changes during the menopause transition: a systematic review

OBJECTIVE

To determine the effectiveness of exercise and/or nutrition interventions and to address body weight changes during the menopause transition.

METHODS

A systematic review of the literature was conducted using electronic databases, grey literature, and hand searching. Two independent researchers screened for studies using experimental designs to evaluate the impact of exercise and/or nutrition interventions on body weight and/or central weight gain performed during the menopausal transition. Studies were quality appraised using Cochrane risk of bias. Included studies were analyzed descriptively.

RESULTS

Of 3,564 unique citations screened, 3 studies were eligible (2 randomized controlled trials, and 1 pre/post study). Study quality ranged from low to high risk of bias. One randomized controlled trial with lower risk of bias concluded that participation in an exercise program combined with dietary interventions might mitigate body adiposity increases, which is normally observed during the menopause transition. The other two studies with higher risk of bias suggested that exercise might attenuate weight loss or weight gain and change abdominal adiposity patterns.

CONCLUSIONS

High quality studies evaluating the effectiveness of interventions targeting body weight changes in women during their menopause transition are needed. Evidence from one higher quality study indicates an effective multifaceted intervention for women to minimize changes in body adiposity.

The role of borderline personality disorder and depression in the relationship between sexual assault and body mass index among women veterans

This article examines lifetime sexual assault (LSA) and mental health history as risk factors associated with body mass index (BMI) in a population of women veterans. This cross-sectional study of a retrospective cohort of 948 Veterans Affairs (VA)-enrolled midwestern enlisted rank women veterans included computer-assisted telephone interviews. Findings show that 33.4% of the participants had a BMI of 30.0 or more meeting the criteria for obesity and 62.5% reported lifetime attempted or completed sexual assault. Greater BMI was positively associated with older age, less education, LSA, depression, and borderline personality disorder (BPD) and negatively associated with current substance use disorder in multivariate models. Mediation analysis found that the relationship between sexual assault and BMI was completely mediated by BPD and depression. Interventions should combine physical and mental health care in gender-specific services for overweight women veterans with trauma histories and mental health conditions.

Estrogen: a master regulator of bioenergetic systems in the brain and body

Estrogen is a fundamental regulator of the metabolic system of the female brain and body. Within the brain, estrogen regulates glucose transport, aerobic glycolysis, and mitochondrial function to generate ATP. In the body, estrogen protects against adiposity, insulin resistance, and type II diabetes, and regulates energy intake and expenditure. During menopause, decline in circulating estrogen is coincident with decline in brain bioenergetics and shift towards a metabolically compromised phenotype. Compensatory bioenergetic adaptations, or lack thereof, to estrogen loss could determine risk of late-onset Alzheimer's disease. Estrogen coordinates brain and body metabolism, such that peripheral metabolic state can indicate bioenergetic status of the brain. By generating biomarker profiles that encompass peripheral metabolic changes occurring with menopause, individual risk profiles for decreased brain bioenergetics and cognitive decline can be created. Biomarker profiles could identify women at risk while also serving as indicators of efficacy of hormone therapy or other preventative interventions.

Sex Differences in the Metabolic Syndrome: Implications for Cardiovascular Health in Women

BACKGROUND

The metabolic syndrome is a clinical condition characterized by the presence of multiple interrelated risk factors for type 2 diabetes and cardiovascular disease. Component features include dysglycemia, increased blood pressure, increased triglycerides, decreased HDL cholesterol concentrations, and obesity (in particular, abdominal obesity). The underlying biology, optimal diagnostic criteria, and clinical implications, once diagnosed, have been matter for intense debate. Despite these areas of controversy, there is now general consensus that the observed risk factor clustering signifies heightened cardiovascular risk.

CONTENT

The influence of sex on the clinical expression and pathophysiology of the syndrome is underrecognized, and is an issue of increasing importance given the alarming increase in prevalence among young women. This minireview will highlight sex differences in the epidemiology, etiology, biology, and clinical expression of the metabolic syndrome. In particular, key sex differences include distinctions in (a) prevalence of dysglycemia, (b) body fat distribution, (c) adipocyte size and function, (d) hormonal regulation of body weight and adiposity, and (e) the influence of estrogen decline on risk factor clustering.

SUMMARY

Accumulated and emerging data convincingly demonstrate that significant heterogeneity exists between men and women developing the metabolic syndrome, in large part related to hormonal regulation of body fat distribution and attendant metabolic abnormalities.

Sexual dimorphism in the effects of exercise on metabolism of lipids to support resting metabolism

Exercise training is generally a healthful activity and an effective intervention for reducing the risk of numerous chronic diseases including cardiovascular disease and diabetes. This is likely both a result of prevention of weight gain over time and direct effects of exercise on metabolism of lipids and the other macronutrient classes. Importantly, a single bout of exercise can alter lipid metabolism and metabolic rate for hours and even into the day following exercise, so individuals who regularly exercise, even if not performed every single day, overall could experience a substantial change in their resting metabolism that would reduce risk for metabolic diseases. However, resting metabolism does not respond similarly in all individuals to exercise participation, and indeed gender or sex is a major determinant of the response of resting lipid metabolism to prior exercise. In order to fully appreciate the metabolic effects and health benefits of exercise, the differences between men and women must be considered. In this article, the differences in the effects of exercise on resting metabolic rate, fuel selection after exercise, as well as the shuttling of triglyceride and fatty acids between tissues are discussed. Furthermore, concepts related to sex differences in the precision of homeostatic control and sex differences in the integration of metabolism between various organs are considered.

Energy metabolism and fertility: a balance preserved for female health

In female animals, energy metabolism and fertility are tightly connected, and reciprocally regulated. However, the relative contributions of metabolic and reproductive pathways have changed over the course of evolution. In oviparous animals, metabolic factors take precedence over fertility, enabling egg production to be inhibited in a nutritionally poor environment. By contrast, in placental mammals, the opposite occurs: the need to feed a developing embryo and neonate forces metabolic pathways to adapt to these reproductive needs. This physiological necessity explains why in female mammals alterations of gonadal activity, including age-dependent cessation of ovarian functions, are associated with a disruption of metabolic homeostasis and consequent inflammatory reactions that trigger the onset of metabolic, cardiovascular, skeletal and neural pathologies. This Review discusses how metabolic homeostasis and reproductive functions interact to optimize female fertility and explains the pathogenic mechanisms underlying the disordered energy metabolism associated with human ovarian dysfunction owing to menopause, polycystic ovary syndrome and Turner syndrome. Finally, this article highlights how hormone replacement therapy might aid the restoration of metabolic homeostasis in women with ovarian dysfunction.

Menopause, complement, and hemostatic markers in women at midlife: the Study of Women's Health Across the Nation

OBJECTIVE

To evaluate whether higher circulating levels of complement proteins C3 and C4 are associated with menopausal status and with hemostatic/thrombus formation markers (circulating factor VII (factor VIIc), fibrinogen, plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator antigen (tPA-ag)) in a sample of midlife women.

METHODS AND RESULTS

A total of 100 women (50 late peri-/postmenopausal and 50 pre-/early peri- menopausal women) from the Study of Women's Health Across the Nation (SWAN) Pittsburgh site were included in the present analysis. Factor VIIc and PAI-1 were log transformed. Linear regression was used for analysis. The mean age of the study participants was 50.5 ± 2.6 years with 73% were Caucasian and 27% were African American. C3 but not C4 was significantly higher in postmenopausal women compared to premenopausal women (P value = 0.03), adjusting for age, race and BMI. In final model (adjusting for age, race, BMI and menopausal status), C3 was associated with higher levels of log PAI-1 (P value = 0.0009) and tPA-ag (P value = 0.0003), while C4 was associated with higher levels of log factor VIIc (P value = 0.04) and fibrinogen (P value = 0.005).

CONCLUSIONS

These data suggest that C3 and C4 may be related to blood clots via their associations with hemostatic markers and that C3 is related to menopausal status. Complement proteins C3 and C4 could be possible pathways by which postmenopausal women are at higher risk of atherosclerosis and cardiovascular related events. It is important to replicate these findings in a larger sample size.

GPER deficiency in male mice results in insulin resistance, dyslipidemia, and a proinflammatory state

Estrogen is an important regulator of metabolic syndrome, a collection of abnormalities including obesity, insulin resistance/glucose intolerance, hypertension, dyslipidemia, and inflammation, which together lead to increased risk of cardiovascular disease and diabetes. The role of the G protein-coupled estrogen receptor (GPER/GPR30), particularly in males, in these pathologies remains unclear. We therefore sought to determine whether loss of GPER contributes to aspects of metabolic syndrome in male mice. Although 6-month-old male and female GPER knockout (KO) mice displayed increased body weight compared with wild-type littermates, only female GPER KO mice exhibited glucose intolerance at this age. Weight gain in male GPER KO mice was associated with increases in both visceral and sc fat. GPER KO mice, however, exhibited no differences in food intake or locomotor activity. One-year-old male GPER KO mice displayed an abnormal lipid profile with higher cholesterol and triglyceride levels. Fasting blood glucose levels remained normal, whereas insulin levels were elevated. Although insulin resistance was evident in GPER KO male mice from 6 months onward, glucose intolerance was pronounced only at 18 months of age. Furthermore, by 2 years of age, a proinflammatory phenotype was evident, with increases in the proinflammatory and immunomodulatory cytokines IL-1β, IL-6, IL-12, TNFα, monocyte chemotactic protein-1, interferon γ-induced protein 10, and monokine induced by interferon gamma and a concomitant decrease in the adipose-specific cytokine adiponectin. In conclusion, our study demonstrates for the first time that in male mice, GPER regulates metabolic parameters associated with obesity and diabetes.

The 40-Something randomized controlled trial to prevent weight gain in mid-age women

Background

Obesity prevention is a major public health priority. Despite the health risks associated with weight gain, there has been a distinct lack of research into effective interventions to prevent, rather than treat, obesity particularly at high risk life stages such as menopause in women. This paper describes the rationale for and design of a 2-year randomized controlled trial (RCT) (the 40-Something Study) aimed at testing the feasibility and efficacy of a relatively low intensity intervention designed to achieve weight control in non-obese women about to enter the menopause transition.

Methods and design

The study is a parallel-group RCT consisting of 12 months of intervention (Phase 1) and 12 months of monitoring (Phase 2). Non-obese pre-menopausal healthy females 44–50 years of age were screened, stratified according to Body Mass Index (BMI) category (18.5-24.9 and 25–29.9 kg/m²) and randomly assigned to one of two groups: motivational interviewing (MI) intervention (n = 28), or a self-directed intervention (SDI) (control) (n = 26). The MI intervention consisted of five consultations with health professionals (four with a Dietitian and one with an Exercise Physiologist) who applied components of MI counselling to consultations with the women over a 12 month period. The SDI was developed as a control and these participants received print materials only. Outcome measures were collected at baseline, three, 12, 18 and 24 months and included weight (primary outcome), waist circumference, body composition, blood pressure, plasma markers of metabolic syndrome risk, dietary intake, physical activity and quality of life. Analysis of covariance will be used to investigate outcomes according to intervention type and duration (comparing baseline, 12 and 24 months).

Discussion

The 40-Something study is the first RCT aimed at preventing menopausal weight gain in Australian women. Importantly, this paper describes the methods used to evaluate whether a relatively low intensity, health professional led intervention will achieve better weight control in pre-menopausal women than a self-directed intervention. The results will add to the scant body of literature on obesity prevention methods at an under-researched high-risk life stage, and inform the development of population-based interventions.

Trial registration

ACTRN12611000064909

[Prevalence of metabolic syndrome and its components in the menopausal transition: a systematic review]

Metabolic syndrome is a complex disorder involving a combination of cardiovascular risk factors. Menopausal transition can be a key factor in the increased prevalence of metabolic syndrome. The current study aims to evaluate the prevalence of metabolic syndrome and its components in the menopausal transition, using a systematic review. Three reviewers conducted an article search in PubMed. The articles' quality was evaluated according to Strengthening the Reporting of Observational Studies in Epidemiology (STROBE). Based on the selected studies, prevalence of metabolic syndrome increases in the post-menopausal (as compared to pre-menopausal) period, regardless of the population and study design. The change was more significant for waist circumference and blood pressure, suggesting that these components have the greatest influence on prevalence of metabolic syndrome.

The cutoff value of waist circumference for predicting metabolic risks in pre- and post-menopausal korean women: analysis of 2010 korean national health and nutrition examination survey data

Background

With metabolic syndrome (MS) being a major risk factor for cardiovascular disease, and central obesity being a major predisposing factor for MS, intensive research is currently being performed on cutoff values according to race and sex. Menopause is an especially significant factor in designating cutoff values for female central obesity, as menopause brings sudden bodily changes that induce central obesity and increased prevalence of MS. Therefore this study aimed to investigate the cutoff values for the obesity index and its validity in predicting the criteria for MS in Korean women according to menstrual status.

Methods

The study focused on 3,103 women 20 years of age or older participating in the 2007 Korea National Health and Nutrition Examination Survey. Definitions of non-adipose components of MS were defined by the International Diabetes Federation, and menstrual status was judged on the basis of survey results. The sensitivity, specificity, and positive and negative predictive values of the central obesity index (body mass index [BMI], waist circumference [WC], waist-to-height ratio [WHtR]) according to menstrual status for two or more non-adipose components of MS were calculated based on the Youden index.

Results

Area under the curve (AUC) values predicting the presence of two or more metabolic risk factors were higher in pre-menopausal women, with AUC values for BMI, WC, and WHtR being, in pre- and post-menopausal women, 23.1 kg/m² vs. 23.9 kg/m², 76.1 cm vs. 82.5 cm, and 0.49 vs. 0.53, respectively. The WC cut off (76 cm) for pre-menopausal women was found to be more sensitive and more effective at screening for MS risks than the cutoff value given by the Korea Society for the Study of Obesity.

Conclusion

The central obesity index showed better predictability for MS risk in pre-menopausal women. Because the central obesity index cutoff values are lower in pre-menopausal women, the possibility of metabolic risk can be considered for pre-menopausal women with WC lower than 85 cm. Assessment and control of other risks are needed accordingly for preventing the development of MS.

Effects of the menopausal transition on dietary intake and appetite: a MONET Group Study

Objective

The purpose of this study was to investigate changes in dietary intake and appetite across the menopausal transition.

Methods

This was a 5-year observational, longitudinal study on the menopausal transition. The study included 94 premenopausal women at baseline (age: 49.9 ± 1.9 yrs; BMI: 23.3 ± 2.3 kg/m²). Body composition (DXA), appetite (visual analogue scale), eating frequency, energy intake (EI) and macronutrient composition (7-day food diary and buffet-type meal) were measured annually.

Results

Repeated-measures analyses revealed that total EI and carbohydrate intake from food diary decreased significantly over time in women who became postmenopausal by year 5 (P > 0.05) compared to women in the menopausal transition. In women who became postmenopausal by year 5, fat and protein intakes decreased across the menopausal transition (0.05 > P < 0.01). Although a decrease in % fat intake was observed during the menopausal transition (P < 0.05), this variable was significantly increased in the postmenopausal years (P < 0.05). Spontaneous EI and protein intake also declined over time and were higher in the years preceding menopause onset (P < 0.05). Desire to eat, hunger and prospective food consumption increased during the menopausal transition and remained at this higher level in the postmenopausal years (0.05 > P< 0.001). Fasting fullness decreased across the menopausal transition (P < 0.05).

Conclusion

These results suggest that menopausal transition is accompanied with a decrease in food intake and an increase in appetite.

Association of leptin levels with radiographic knee osteoarthritis among a cohort of midlife women

OBJECTIVE

To relate serum leptin levels to prevalent and incident radiographic knee osteoarthritis (OA) and to determine if patterns of change in longitudinal serum leptin measures differ by knee OA status over a 10-year period.

METHODS

Participants in the Michigan Study of Women's Health Across the Nation underwent bilateral knee radiographs at baseline and followup visits 2, 4, and 11 for ascertainment of knee OA status (Kellgren/Lawrence score ≥2). Serum leptin measures were available from baseline and followup visits 1 and 3-7.

RESULTS

The baseline prevalence of knee OA (mean age 46 years) was 18%; the 2-year incidence of knee OA at followup visits 2 and 4 was 18% and 14%, respectively. Serum leptin levels were associated with prevalent and incident knee OA. A 5 ng/ml increase in serum leptin level was associated with 38% higher odds of prevalent knee OA (odds ratio [OR] 1.38, 95% confidence interval [95% CI] 1.26-1.52) and 31% greater odds of incident knee OA (OR 1.31, 95% CI 1.21-1.41) after adjustment for covariates, including body mass index residuals. Leptin levels increased with time; on average, serum leptin levels increased by 0.38 ng/ml per year (P = 0.0004). Women with incident knee OA during the 10-year followup period had consistently higher serum leptin levels as compared to women with no knee OA during followup.

CONCLUSION

Our findings support a metabolic role of obesity in knee OA. A better understanding of the mechanisms by which increased fat mass is associated with joint damage is needed. Management of cardiometabolic dysfunction, including elevated serum leptin levels, may be beneficial in forestalling the onset or progression of knee OA.

Light physical activity is a better determinant of lower adiposity during the menopausal transition

OBJECTIVE

To investigate the relationship between time spent performing physical activity (PA) and adiposity across the menopausal transition.

METHODS

Body weight and body composition were analyzed in 65 women (47-54 years old; body mass index 23.2 ± 2.4 kg/m(2)) in a 5-year prospective study. Time spent in PA of varying intensities (sedentary, light, moderate and vigorous) was determined from 7-day accelerometer measurement and energy intake with a 7-day food diary.

RESULTS

Significant negative correlations were observed between the time spent in light-intensity PA and fat mass (FM) (r = -0.38, p < 0.005), central FM (r = -0.36, p < 0.005), peripheral FM (r = -0.33, p < 0.01), and percent body fat (r = -0.42, p < 0.001) at year 1, respectively. No significant correlations were noted between measures of adiposity and time spent performing either moderate or vigorous PA. Analyses using tertiles of time spent in light PA at year 1 showed that FM (20.7 ± 4.0 vs. 20.3 ± 6.6 vs. 16.6 ± 4.6 kg, p < 0.05), central FM (10.1 ± 2.6 vs. 10.0 ± 3.8 vs. 7.8 ± 2.4 kg; p < 0.05) and percent body fat (34.5 ± 5.1 vs. 32.2 ± 7.7 vs. 28.1 ± 6.2%, p < 0.01) were all significantly lower in women in the highest tertile. These differences remained significant after covariate analyses using time spent in moderate- and high-intensity PA and total energy intake. Finally, lower levels of FM, percent body fat, central and peripheral FM persisted in women who spent more time in light PA (highest tertiles) over the 5-year follow-up.

CONCLUSION

Our results suggest that the time spent performing light PA may have a greater impact on adiposity than moderate and/or vigorous PA, an observation independent of the menopausal status.

Sex differences in the physiology of eating

Hypothalamic-pituitary-gonadal (HPG) axis function fundamentally affects the physiology of eating. We review sex differences in the physiological and pathophysiological controls of amounts eaten in rats, mice, monkeys, and humans. These controls result from interactions among genetic effects, organizational effects of reproductive hormones (i.e., permanent early developmental effects), and activational effects of these hormones (i.e., effects dependent on hormone levels). Male-female sex differences in the physiology of eating involve both organizational and activational effects of androgens and estrogens. An activational effect of estrogens decreases eating 1) during the periovulatory period of the ovarian cycle in rats, mice, monkeys, and women and 2) tonically between puberty and reproductive senescence or ovariectomy in rats and monkeys, sometimes in mice, and possibly in women. Estrogens acting on estrogen receptor-α (ERα) in the caudal medial nucleus of the solitary tract appear to mediate these effects in rats. Androgens, prolactin, and other reproductive hormones also affect eating in rats. Sex differences in eating are mediated by alterations in orosensory capacity and hedonics, gastric mechanoreception, ghrelin, CCK, glucagon-like peptide-1 (GLP-1), glucagon, insulin, amylin, apolipoprotein A-IV, fatty-acid oxidation, and leptin. The control of eating by central neurochemical signaling via serotonin, MSH, neuropeptide Y, Agouti-related peptide (AgRP), melanin-concentrating hormone, and dopamine is modulated by HPG function. Finally, sex differences in the physiology of eating may contribute to human obesity, anorexia nervosa, and binge eating. The variety and physiological importance of what has been learned so far warrant intensifying basic, translational, and clinical research on sex differences in eating.

The associations of multiple dimensions of discrimination and abdominal fat in African American adults: the Jackson Heart Study

BACKGROUND

Discrimination may be adversely associated with abdominal obesity, but few studies have examined associations with abdominal fat.

PURPOSE

The purpose of this study was to examine whether discrimination was independently associated with visceral (VAT) and subcutaneous (SAT) fat and whether these associations differed by sex and age.

METHODS

Participants self-reported experiences of everyday and lifetime discrimination. The main reason for and the coping response to these experiences were also reported. VAT and SAT were quantified by computed tomography.

RESULTS

In fully adjusted models, higher reports of everyday discrimination were associated with greater SAT, but not VAT, volumes in men only: SAT increased by 3.6 (standard error = 1.8) cm(3) for each unit increase in the everyday discrimination score. In women, higher reports of lifetime non-racial discrimination were associated with greater VAT (71.6 ± 32.0, P < 0.05) and SAT (212.6 ± 83.6, P < 0.05), but these relationships were attenuated after controlling for body mass index.

CONCLUSIONS

These cross-sectional findings do not fully support the independent hypothesis of discrimination and abdominal fat. Additional investigations involving longitudinal designs are warranted.

Estradiol effects on subcutaneous adipose tissue lipolysis in premenopausal women are adipose tissue depot specific and treatment dependent

Estrogen has direct effects within adipose tissue and has been implicated in regional adiposity; however, the influence of estrogen on in vivo lipolysis is unclear. The purpose of this study was to investigate the effect of local 17β-estradiol (E(2)) on subcutaneous adipose tissue (SAT) lipolysis in premenopausal women. In vivo lipolysis (dialysate glycerol) was measured in 17 women (age 27.4 ± 2.0 yr, BMI 29.7 ± 0.5 kg/m(2)) via microdialysis of abdominal (AB) and gluteal (GL) SAT. Glycerol was measured at baseline and during acute interventions to increase lipolysis including local perfusion of isoproterenol (ISO, β-adrenergic agonist, 1.0 μmol/l), phentolamine (PHEN, α-adrenergic antagonist, 0.1 mmol/l), and submaximal exercise (60% Vo(2peak), 30 min); all with and without coperfusion of E(2) (500 nmol/l). E(2) coperfusion blunted the lipolytic response to ISO in AB (E(2) 196 ± 31%, control 258 ± 26%, P = 0.003) but not in GL (E(2) 113 ± 14%, control 111 ± 12%, P = 0.43) adipose tissue. At rest, perfusion of PHEN with ISO did not change dialysate glycerol. Submaximal exercise during ISO + PHEN increased dialysate glycerol in the AB (56 ± 9%) and GL (62 ± 12%) regions. Probes perfused with E(2) during exercise and ISO + PHEN had an increased lipolytic response in AB (90 ± 9%, P = 0.007) but a lower response in GL (35 ± 7%, P = 0.05) SAT compared with no-E(2) conditions. E(2) effects on lipolysis are region specific and may work through both adrenergic and adrenergic-independent mechanisms to potentiate and/or blunt SAT lipolysis in premenopausal women.

Menopause is associated with decreased whole body fat oxidation during exercise

The purpose of this study was to examine if fat oxidation was affected by menopausal status and to investigate if this could be related to the oxidative capacity of skeletal muscle. Forty-one healthy women were enrolled in this cross-sectional study [premenopausal (n = 19), perimenopausal (n = 8), and postmenopausal (n = 14)]. Estimated insulin sensitivity was obtained from an oral glucose tolerance test. Body composition was measured by dual-energy X-ray absorptiometry and magnetic resonance imaging. Fat oxidation and energy expenditure were measured during an acute exercise bout of 45 min of ergometer biking at 50% of maximal oxygen consumption (Vo2 max). Muscle biopsies from the vastus lateralis of the quadriceps muscle were obtained before and immediately after the exercise bout. Postmenopausal women had 33% [confidence interval (CI) 95%: 12-55] lower whole body fat oxidation (P = 0.005) and 19% (CI 95%: 9-22) lower energy expenditure (P = 0.02) during exercise, as well as 4.28 kg lower lean body mass (LBM) than premenopausal women. Correction for LBM reduced differences in fat oxidation to 23% (P = 0.05), whereas differences in energy expenditure disappeared (P = 0.22). No differences between groups were found in mRNA [carnitine palmitoyltransferase I, β-hydroxyacyl-CoA dehydrogenase (β-HAD), peroxisome proliferator-activated receptor-α, citrate synthase (CS), pyruvate dehydrogenase kinase 4, peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α)], protein [phosphorylated AMP-activated protein kinase (AMPK), vascular endothelial growth factor, pyruvate dehydrogenase-1Eα, cytochrome oxidase I], or enzyme activities (β-HAD, CS) in resting skeletal muscle, except for an increased protein level of cytochrome c in the post- and perimenopausal women relative to premenopausal women. Postmenopausal women demonstrated a trend to a blunted exercise-induced increase in phosphorylation of AMPK compared with premenopausal women (P = 0.06). We conclude that reduced whole body fat oxidation after menopause is associated with reduced LBM.

Sex-stratified genome-wide association studies including 270,000 individuals show sexual dimorphism in genetic loci for anthropometric traits

Given the anthropometric differences between men and women and previous evidence of sex-difference in genetic effects, we conducted a genome-wide search for sexually dimorphic associations with height, weight, body mass index, waist circumference, hip circumference, and waist-to-hip-ratio (133,723 individuals) and took forward 348 SNPs into follow-up (additional 137,052 individuals) in a total of 94 studies. Seven loci displayed significant sex-difference (FDR<5%), including four previously established (near GRB14/COBLL1, LYPLAL1/SLC30A10, VEGFA, ADAMTS9) and three novel anthropometric trait loci (near MAP3K1, HSD17B4, PPARG), all of which were genome-wide significant in women (P<5×10(-8)), but not in men. Sex-differences were apparent only for waist phenotypes, not for height, weight, BMI, or hip circumference. Moreover, we found no evidence for genetic effects with opposite directions in men versus women. The PPARG locus is of specific interest due to its role in diabetes genetics and therapy. Our results demonstrate the value of sex-specific GWAS to unravel the sexually dimorphic genetic underpinning of complex traits.

Association of bilateral oophorectomy and body fatness in a representative sample of US women

OBJECTIVE

Preclinical studies suggest that abrupt hormone deprivation caused by oophorectomy, leads to obesity and its metabolic sequelae. The purpose of the current study was to examine the association between oophorectomy and body fatness in a nationally representative sample of women.

METHODS

The association between prior oophorectomy and nine adiposity measures was examined using data from the Third National Health and Nutrition Examination Survey (NHANES III, 1988-1994). The analytic population included cancer-free women age 40 or older (N=3549) who underwent standardized body measurements and reported on whether or not they had a bilateral oophorectomy. Multivariate linear and polytomous logistic regressions were used to evaluate the association of oophorectomy with multiple measures of adiposity.

RESULTS

Mean percent body fat, skinfold thickness, waist circumference and body mass index were significantly higher in women with oophorectomy before age 40 compared to those with intact ovaries, but no difference was observed in women with oophorectomy at an older age. Women who underwent an early oophorectomy were nearly three times more likely than women with intact ovaries to have percent body fat in the highest tertile compared to the lowest tertile (OR=2.82, 95% CI 1.39-5.75). Excluding hormone therapy (HT) users yielded stronger associations.

CONCLUSION

Bilateral oophorectomy in young women is strongly associated with an increase in percent body fat, a well-established risk factor for cancer and other chronic diseases. Measuring body fat in addition to BMI may provide a more comprehensive assessment of adiposity in these women.

The role of estrogens in control of energy balance and glucose homeostasis

Estrogens play a fundamental role in the physiology of the reproductive, cardiovascular, skeletal, and central nervous systems. In this report, we review the literature in both rodents and humans on the role of estrogens and their receptors in the control of energy homeostasis and glucose metabolism in health and metabolic diseases. Estrogen actions in hypothalamic nuclei differentially control food intake, energy expenditure, and white adipose tissue distribution. Estrogen actions in skeletal muscle, liver, adipose tissue, and immune cells are involved in insulin sensitivity as well as prevention of lipid accumulation and inflammation. Estrogen actions in pancreatic islet β-cells also regulate insulin secretion, nutrient homeostasis, and survival. Estrogen deficiency promotes metabolic dysfunction predisposing to obesity, the metabolic syndrome, and type 2 diabetes. We also discuss the effect of selective estrogen receptor modulators on metabolic disorders.

Progression rates of carotid intima-media thickness and adventitial diameter during the menopausal transition

OBJECTIVE

The aim of this study is to assess whether the levels and progression rates of carotid intima-media thickness (IMT) and adventitial diameter (AD) vary by menopausal stage.

METHODS

Two hundred forty-nine women (aged 42-57 y; 49% premenopausal and 46% early perimenopausal) from the Study of Women's Health Across the Nation were included in the current analysis. Participants were followed up for up to 9 years (median, 3.7 y) and underwent up to five carotid scans. Linear mixed-effect models were used for the analysis.

RESULTS

The overall rate of change in IMT was 0.007 mm/year. Independent of age and race, the progression rate of IMT increased substantially in the late perimenopausal stage (0.017 mm/y) compared with both the premenopausal stage (0.007 mm/y) and the early perimenopausal stage (0.005 mm/y; P ≤ 0.05). For AD, although the overall rate of change was negative (-0.009 mm/y), significant positive increases in the rate of change were observed in the late perimenopausal stage (0.024 mm/y) and the postmenopausal stage (0.018 mm/y) compared with the premenopausal stage (-0.032 mm/y; P < 0.05). In the final models, the postmenopausal stage was independently associated with higher levels of IMT and AD (P < 0.05) compared with the premenopausal stage.

CONCLUSIONS

During the menopausal transition, the carotid artery undergoes adaptation that is reflected in adverse changes in IMT and AD. These changes may have an impact on the vulnerability of the vessel to disease in older women.

Sex dimorphism and depot differences in adipose tissue function

Obesity, characterized by excessive adiposity, is a risk factor for many metabolic pathologies, such as type 2 diabetes mellitus (T2DM). Numerous studies have shown that adipose tissue distribution may be a greater predictor of metabolic health. Upper-body fat (visceral and subcutaneous abdominal) is commonly associated with the unfavorable complications of obesity, while lower-body fat (gluteal-femoral) may be protective. Current research investigations are focused on analyzing the metabolic properties of adipose tissue, in order to better understand the mechanisms that regulate fat distribution in both men and women. This review will highlight the adipose tissue depot- and sex-dependent differences in white adipose tissue function, including adipogenesis, adipose tissue developmental patterning, the storage and release of fatty acids, and secretory function. This article is part of a Special Issue entitled: Modulation of Adipose Tissue in Health and Disease.

From passive overeating to "food addiction": a spectrum of compulsion and severity

A psychobiological dimension of eating behaviour is proposed, which is anchored at the low end by energy intake that is relatively well matched to energy output and is reflected by a stable body mass index (BMI) in the healthy range. Further along the continuum are increasing degrees of overeating (and BMI) characterized by more severe and more compulsive ingestive behaviours. In light of the many similarities between chronic binge eating and drug abuse, several authorities have adopted the perspective that an apparent dependence on highly palatable food-accompanied by emotional and social distress-can be best conceptualized as an addiction disorder. Therefore, this review also considers the overlapping symptoms and characteristics of binge eating disorder (BED) and models of food addiction, both in preclinical animal studies and in human research. It also presents this work in the context of the modern and "toxic" food environment and therein the ubiquitous triggers for over-consumption. We complete the review by providing evidence that what we have come to call "food addiction" may simply be a more acute and pathologically dense form of BED.

Overweight, obesity and related non-communicable diseases in Asian Indian girls and women

The prevalence of obesity is rising globally and in India. Overweight, obesity and related diseases need to be delineated in Asian Indian women. A literature search was done using key words like 'obesity', 'Asian Indian women', 'body fat distribution', 'type 2 diabetes', 'fertility', 'polycystic ovarian disease', metabolic syndrome', 'cardiovascular disease', 'non-alcoholic fatty liver disease', 'gender', 'sex' and 'prevalence' up to September 2012 in Pubmed and Google Scholar search engines. This review highlights the Asian Indian body composition with regards to obesity and provides a collated perspective of gender-specific prevalence of the co-morbidities. Recent data show that women (range of prevalence of overweight and obesity from different studies 15-61%) have higher prevalence of overweight and obesity as compared with men (range of prevalence of overweight and obesity from different studies 12-54%) in India and that obesity is increasing in the youth. The prevalence of overweight and obesity in both men and women steeply rose in a Punjabi community from Jaipur. Importantly, prevalence of abdominal obesity has been consistently higher in women than in men. The lowest prevalence (6.0%) of type 2 diabetes mellitus in women is reported from South India (rural Andhra Pradesh; 2006) and the highest (14.0%) by the National Urban Diabetes Survey (2001). Although the clustering of cardiovascular disease risk factors was generally high, it increased further in post-menopausal women. There are a number of factors that predispose Indian women to obesity; sedentary behaviour, imbalanced diets, sequential and additive postpartum weight gain and further decrease in physical activity during this period and cultural issues. In view of these data, preventive measures should be specifically targeted to Indian women.

Adipocyte fatty acid storage factors enhance subcutaneous fat storage in postmenopausal women

Increases in weight have been associated with corresponding increases in insulin resistance in postmenopausal women. Although estrogen has significant impact on body fat and body fat distribution, the cellular mechanisms that influence this process are not yet known. We measured adipose tissue fatty acid (FA) storage and FA storage factors in 12 premenopausal and 11 postmenopausal women matched for age and body composition. Postmenopausal women had lower postprandial FA oxidation (indirect calorimetry), greater meal FA, and direct free FA (FFA) storage than premenopausal women, including two-fold greater meal FA storage in the femoral depot. The fed/fasted activities of adipose tissue lipoprotein lipase were not significantly different between premenopausal and postmenopausal women. In contrast, adipocyte acyl-CoA synthetase and diacylglycerol acyltransferase activities in postmenopausal women were significantly upregulated and were positively correlated with direct FFA storage rates. These findings suggest that the propensity for subcutaneous adipose tissue FA storage is increased in postmenopausal women, more so from changes in adipocyte FA storage factors than from adipose tissue lipoprotein lipase activity. Our results suggest that female sex steroids, most likely estrogen, have important effects on adipose tissue FA storage and FA oxidation that could promote fat gain in postmenopausal women.

Cellular mechanism by which estradiol protects female ovariectomized mice from high-fat diet-induced hepatic and muscle insulin resistance

Estrogen replacement therapy reduces the incidence of type 2 diabetes in postmenopausal women; however, the mechanism is unknown. Therefore, the aim of this study was to evaluate the metabolic effects of estrogen replacement therapy in an experimental model of menopause. At 8 weeks of age, female mice were ovariectomized (OVX) or sham (SHAM) operated, and OVX mice were treated with vehicle (OVX) or estradiol (E2) (OVX+E2). After 4 weeks of high-fat diet feeding, OVX mice had increased body weight and fat mass compared with SHAM and OVX+E2 mice. OVX mice displayed reduced whole-body energy expenditure, as well as impaired glucose tolerance and whole-body insulin resistance. Differences in whole-body insulin sensitivity in OVX compared with SHAM mice were accounted for by impaired muscle insulin sensitivity, whereas both hepatic and muscle insulin sensitivity were impaired in OVX compared with OVX+E2 mice. Muscle diacylglycerol (DAG), content in OVX mice was increased relative to SHAM and OVX+E2 mice. In contrast, E2 treatment prevented the increase in hepatic DAG content observed in both SHAM and OVX mice. Increases in tissue DAG content were associated with increased protein kinase Cε activation in liver of SHAM and OVX mice compared with OVX+E2 and protein kinase Cθ activation in skeletal muscle of OVX mice compared with SHAM and OVX+E2. Taken together, these data demonstrate that E2 plays a pivotal role in the regulation of whole-body energy homeostasis, increasing O(2) consumption and energy expenditure in OVX mice, and in turn preventing diet-induced ectopic lipid (DAG) deposition and hepatic and muscle insulin resistance.

Pathophysiology of human visceral obesity: an update

Excess intra-abdominal adipose tissue accumulation, often termed visceral obesity, is part of a phenotype including dysfunctional subcutaneous adipose tissue expansion and ectopic triglyceride storage closely related to clustering cardiometabolic risk factors. Hypertriglyceridemia; increased free fatty acid availability; adipose tissue release of proinflammatory cytokines; liver insulin resistance and inflammation; increased liver VLDL synthesis and secretion; reduced clearance of triglyceride-rich lipoproteins; presence of small, dense LDL particles; and reduced HDL cholesterol levels are among the many metabolic alterations closely related to this condition. Age, gender, genetics, and ethnicity are broad etiological factors contributing to variation in visceral adipose tissue accumulation. Specific mechanisms responsible for proportionally increased visceral fat storage when facing positive energy balance and weight gain may involve sex hormones, local cortisol production in abdominal adipose tissues, endocannabinoids, growth hormone, and dietary fructose. Physiological characteristics of abdominal adipose tissues such as adipocyte size and number, lipolytic responsiveness, lipid storage capacity, and inflammatory cytokine production are significant correlates and even possible determinants of the increased cardiometabolic risk associated with visceral obesity. Thiazolidinediones, estrogen replacement in postmenopausal women, and testosterone replacement in androgen-deficient men have been shown to favorably modulate body fat distribution and cardiometabolic risk to various degrees. However, some of these therapies must now be considered in the context of their serious side effects. Lifestyle interventions leading to weight loss generally induce preferential mobilization of visceral fat. In clinical practice, measuring waist circumference in addition to the body mass index could be helpful for the identification and management of a subgroup of overweight or obese patients at high cardiometabolic risk.

Physical activity and cardiovascular risk factors at menopause: the Nord-Trøndelag health study

BACKGROUND

Lowered physical activity levels may partially explain changes in metabolic risk factors in women after menopause.

OBJECTIVES

To evaluate the association between physical activity and metabolic risk factors at baseline and after 11 years, as well as the change in that association over time in women who were premenopausal and ≥ 40 years at baseline.

METHODS

Subjects in a Norwegian population-based health survey answered questionnaires and had body and serum measurements during 1995-1997 (HUNT 2) and in a follow-up study during 2006-2008 (HUNT 3). Repeated-measures analyses were used to estimate the association between physical activity and metabolic factors, adjusting for age, smoking status, education, alcohol intake, and parity. Adjustment for hormonal treatment and medication was made, as appropriate.

RESULTS

In women remaining premenopausal, a higher physical activity score in HUNT 3 was associated with lower weight (p < 0.01) and waist-hip ratio (p < 0.01) and higher high density lipoprotein (HDL) cholesterol in HUNT 3 (p < 0.01). In women that were postmenopausal by the time of follow-up, a higher physical activity score in HUNT 3 was associated with lower weight (p < 0.01), waist-hip ratio (p < 0.01), triglycerides (p < 0.01), and higher total cholesterol (p < 0.05), HDL cholesterol (p < 0.01), and diastolic blood pressure (p < 0.05) in HUNT 3. The association of total physical activity score with weight and waist-hip ratio was stronger in HUNT 3 than in HUNT 2 (p < 0.01).

CONCLUSION

Increased physical activity may reduce the risk of adverse outcomes and use of pharmacological management in women of menopausal age.

Effects of the menopausal transition on energy expenditure: a MONET Group Study

Objectives

Factors that influence weight gain during the menopausal transition are not fully understood. The purpose of this study was to investigate changes in energy expenditure (EE) across the menopausal transition.

Methods

One hundred and two premenopausal women (age: 49.9 ± 1.9 yrs; BMI: 23.3 ± 2.2 kg/m²) were followed for 5 years. Body composition (DXA), physical activity EE (accelerometer), resting EE and thermic effect of food (indirect calorimetry) were measured annually.

Results

Total EE decreased significantly over time in postmenopausal women (P < 0.05), which was mostly due to a decrease in physical activity EE (P < 0.05). Although average resting EE remained stable over time in postmenopausal women, a significant increase, over the 5-year period, was noted in women who were in the menopausal transition by year 5 (P < 0.05). Finally, the time spent in moderate physical activity decreased and the time spent in sedentary physical activity increased during the menopausal transition (P < 0.05).

Conclusion

These results suggest that menopausal transition is accompanied with a decline in EE mainly characterized by a decrease in physical activity EE and a shift to a more sedentary lifestyle.

Cut-off value of body fat in association with metabolic syndrome in Thai peri- and postmenopausal women

BACKGROUND

Pathophysiologic changes during the menopause transition may contribute to the risk of metabolic syndrome (MetS). Body fat composition, particularly visceral fat, is highly associated with increased insulin resistance, abnormal carbohydrate metabolism and high blood pressure. We purposefully wished to determine the optimal cut-off values of body fat composition, including visceral fat, in order to predict MetS and to assess the prevalence of MetS in peri- and postmenopausal women.

METHODS

This cross-sectional study was conducted in a population-based, prospective cohort at the Menopause and Gynecology clinics, King Chulalongkorn Memorial Hospital. Body fat percentage and visceral fat rating were measured by a bioelectrical impedance analyzer (Tanita SC 330). MetS was diagnosed using the Harmonizing criteria of A Joint Interim Statement of IDF/NHLBI/AHA/WHF/IAS/IASO 2009. Receiver operating characteristic analyses were performed to determine the optimal cut-off values of body fat, visceral fat, waist circumference and body mass index to identify peri- and postmenopausal women at risk of MetS.

RESULTS

Ninety-two perimenopausal and 446 postmenopausal women aged 40-60 years were recruited for the analyses. The optimal cut-off values for body fat percentage, visceral fat rating, waist circumference and body mass index for identifying women at risk of MetS were 34%, 7, 88 cm and 24 kg/m(2), respectively. The prevalence of MetS in this study was 27.9%.

CONCLUSION

The optimal cut-off values to predict MetS of body fat percentage, visceral fat and waist circumference were established. Using the Harmonizing 2009 criteria, we found that approximately one out of four peri- and postmenopausal women in this study had MetS.