The metabolic syndrome: an emerging health epidemic in women

Differential effects of Akkermansia-enriched fecal microbiota transplant on energy balance in female mice on high-fat diet

Estrogens protect against weight gain and metabolic disruption in women and female rodents. Aberrations in the gut microbiota composition are linked to obesity and metabolic disorders. Furthermore, estrogen-mediated protection against diet-induced metabolic disruption is associated with modifications in gut microbiota. In this study, we tested if estradiol (E2)-mediated protection against obesity and metabolic disorders in female mice is dependent on gut microbiota. Specifically, we tested if fecal microbiota transplantation (FMT) from E2-treated lean female mice, supplemented with or without Akkermansia muciniphila, prevented high fat diet (HFD)-induced body weight gain, fat mass gain, and hyperglycemia in female recipients. FMT from, and cohousing with, E2-treated lean donors was not sufficient to transfer the metabolic benefits to the E2-deficient female recipients. Moreover, FMT from lean donors supplemented with A. muciniphila exacerbated HFD-induced hyperglycemia in E2-deficient recipients, suggesting its detrimental effect on the metabolic health of E2-deficient female rodents fed a HFD. Given that A. muciniphila attenuates HFD-induced metabolic insults in males, the present findings suggest a sex difference in the impact of this microbe on metabolic health.

Distinct Changes in Gut Microbiota Are Associated with Estradiol-Mediated Protection from Diet-Induced Obesity in Female Mice

A decrease in ovarian estrogens in postmenopausal women increases the risk of weight gain, cardiovascular disease, type 2 diabetes, and chronic inflammation. While it is known that gut microbiota regulates energy homeostasis, it is unclear if gut microbiota is associated with estradiol regulation of metabolism. In this study, we tested if estradiol-mediated protection from high-fat diet (HFD)-induced obesity and metabolic changes are associated with longitudinal alterations in gut microbiota in female mice. Ovariectomized adult mice with vehicle or estradiol (E2) implants were fed chow for two weeks and HFD for four weeks. As reported previously, E2 increased energy expenditure, physical activity, insulin sensitivity, and whole-body glucose turnover. Interestingly, E2 decreased the tight junction protein occludin, suggesting E2 affects gut epithelial integrity. Moreover, E2 increased Akkermansia and decreased Erysipleotrichaceae and Streptococcaceae. Furthermore, Coprobacillus and Lactococcus were positively correlated, while Akkermansia was negatively correlated, with body weight and fat mass. These results suggest that changes in gut epithelial barrier and specific gut microbiota contribute to E2-mediated protection against diet-induced obesity and metabolic dysregulation. These findings provide support for the gut microbiota as a therapeutic target for treating estrogen-dependent metabolic disorders in women.

Chronic Stress Combined with a Fructose Diet Reduces Hypothalamic Insulin Signaling and Antioxidative Defense in Female Rats

BACKGROUND

Increased fructose consumption and chronic exposure to stress have been associated with the development of obesity and insulin resistance. In the hypothalamus, a crossroad of stress responses and energy balance, insulin and glucocorticoids regulate the expression of orexigenic neuropeptides, neuropeptide Y (NPY) and agouti-related protein (AgRP), and anorexigenic neuropeptides, proopio-melanocortin (POMC) and cocaine- and amphetamine-regulated transcript (CART).

OBJECTIVES

We investigated whether chronic stress and fructose diet disrupt these hormonal signaling pathways and appetite control in the hypothalamus, contributing to the development of insulin resistance and obesity. Potential roles of hypothalamic inflammation and oxidative stress in the development of insulin resistance were also analyzed.

METHODS

Insulin, glucocorticoid, and leptin signaling, expression of orexigenic and anorexigenic neuropeptides, and antioxidative and inflammatory statuses in the whole hypothalamus of fructose-fed female rats exposed to unpredictable stress for 9 weeks were analyzed using quantitative PCR and Western blotting.

RESULTS

Chronic stress combined with a fructose-enriched diet reduced protein content and stimulatory phosphorylation of Akt kinase, and elevated 11β-hydroxysteroid dehydrogenase 1 and glucocorticoid receptor expression, while alterations in appetite regulation (NPY, AgRP, POMC, CART, leptin receptor, and SOCS3 expression) were not observed. The expression of antioxidative defense enzymes (mitochondrial manganese superoxide dismutase 2, glutathione reductase, and catalase) and proinflammatory cytokines (IL-1β, IL-6, and TNFα) was reduced.

CONCLUSIONS

Our results underline the combination of long-term stress exposure and fructose overconsumption as more detrimental for hypothalamic function than for either of the factors separately, as it enhanced glucocorticoid and impaired insulin signaling, antioxidative -defense, and inflammatory responses of this homeostasis- regulating center.

Membrane-Initiated Estrogen Receptor Signaling Mediates Metabolic Homeostasis via Central Activation of Protein Phosphatase 2A

Women gain weight and their diabetes risk increases as they transition through menopause; these changes can be partly reversed by hormone therapy. However, the underlying molecular mechanisms mediating these effects are unknown. A novel knock-in mouse line with the selective blockade of the membrane-initiated estrogen receptor (ER) pathway was used, and we found that the lack of this pathway precipitated excessive weight gain and glucose intolerance independent of food intake and that this was accompanied by impaired adaptive thermogenesis and reduced physical activity. Notably, the central activation of protein phosphatase (PP) 2A improved metabolic disorders induced by the lack of membrane-initiated ER signaling. Furthermore, the antiobesity effect of estrogen replacement in a murine menopause model was abolished by central PP2A inactivation. These findings define a critical role for membrane-initiated ER signaling in metabolic homeostasis via the central action of PP2A.

Intensive lifestyle modification program on weight loss and metabolic syndrome risk reduction among obese women in rural areas of Thailand

Purpose

The purpose of this paper is to examine the effect of the intensive lifestyle modification program on weight and metabolic syndrome risk reduction in rural obese women who have no underlying non-communicable diseases in Thailand.

Design/methodology/approach

A randomized controlled trial was conducted. In total, 60 healthy obese women aged 30-50 years were recruited and randomly assigned to either the intervention (n=30) or control (n=30) group after health screening. Tailored nutritional counseling, health education and exercise training were included in the lifestyle modification program. Behavioral modification techniques were also incorporated. The intervention was conducted weekly for the first eight weeks, then biweekly until week 16.

Findings

The student’s t-test was used to compare mean difference between groups. The total weight loss in the intervention group (n=29) was significantly higher, 7.6±2.9 kg, compared with the control group (n=30) who lost 0.7±1.4 kg (p<0.001). The intervention group lost weight 10.2 percent from baseline which was significantly higher than that in the control group (p<0.001). Systolic and diastolic blood pressures, fasting blood sugar, and waist circumference were significantly improved. Triglyceride levels slightly improved while high density lipoprotein cholesterol was slightly lowered. The intervention group showed a statistical reduction in abnormal components of metabolic syndrome compared with the control group, with the relative risk=0.24, 95% confidence interval=0.072-0.791, and p=0.018.

Originality/value

Compatibility of the program activities conducted by a health professional who had achieved healthy weight loss and accepted as a role model was a key to achieving effective weight loss and metabolic syndrome risk reduction in obese women in rural areas. The program should be integrated into the conventional practice of health care centers.

Excessive daytime sleepiness and metabolic syndrome: a cross-sectional study

OBJECTIVE

Excessive daytime sleepiness (EDS) has been associated with singular independent symptoms of metabolic syndrome, such as insulin resistance and diabetes. The aim of this study was to assess whether this relationship is sustained among individuals who meet criteria for the whole syndrome.

MATERIALS/METHODS

994 Women aged 21-94 years (median 50.2 years, IQR 34-65) and 840 men aged 24-92 years (median 60.4 years, IQR 47-73) who resided in the Barwon Statistical Division, South-Eastern Australia, and participated in the Geelong Osteoporosis Study (GOS) between the years of 2001 and 2008. Anthropometric measurements, lifestyle, mood, demographic and health-related factors were obtained. Sleep duration was categorized as short (<6 h), average (6-9 h) and long (>9 h). Sleepiness was assessed using the Epworth Sleepiness Scale (ESS), and scores of ≥ 10 indicated EDS. The presence of metabolic syndrome was assessed using a modified version of criteria as outlined by the International Diabetics Federations recommendations (2005).

RESULTS

Women: 138 (14.0%) of the women reported EDS; those with EDS were heavier, had a greater body mass index (BMI) and were more likely to have metabolic syndrome. The association between EDS and metabolic syndrome was sustained following adjustment for age and hours sleep (adjusted OR=1.90, 95% CI 1.16-3.09), however BMI attenuated the relationship (adjusted OR=1.64, 95% CI =1.05-2.57). These findings were independent of smoking status, alcohol intake, medication use, socioeconomic status, physical activity and current diagnosis of a depressive illness. Men: 111 (13.2%) of the men reported EDS; those with EDS had a greater waist circumference and were more likely to have metabolic syndrome. Analysis of age-stratified data (<60 years vs. ≥60 years) revealed that the older men with EDS were more likely to have metabolic syndrome (OR=1.71, 95% CI 1.01-2.92), however, age explained this association (age adjusted OR=1.51, 95% CI 0.88-2.60). In the younger age group, no association was detected between EDS and metabolic syndrome. For both men and women, the prevalence of combined EDS and metabolic syndrome increased progressively with age.

CONCLUSION

For women, the association between EDS and metabolic syndrome appears to be driven by adiposity measures; while for men, the association is somewhat attributed to older age. Additional research is required to assess temporal associations with underlying sleep pathology.

Rice koji reduced body weight gain, fat accumulation, and blood glucose level in high-fat diet-induced obese mice

Rice koji is considered a readily accessible functional food that may have health-promoting effects. We investigated whether white, yellow, and red koji have the anti-obesity effect in C57BL/6J mice fed a high-fat diet (HFD), which is a model for obesity. Mice were fed HFD containing 10% (w/w) of rice koji powder or steamed rice for 4 weeks. Weight gain, epididymal white adipose tissue, and total adipose tissue weight were significantly lower in all rice koji groups than in the HFD-rice group after 4 weeks. Feed efficiency was significantly reduced in the yellow koji group. Blood glucose levels were significantly lower in the white and red koji groups with HOMA-R and leptin levels being reduced in the white koji group. White and red koji increased glucose uptake and GLUT4 protein expression in L6 myotube cells. These results showed that all rice koji have the anti-obesity or anti-diabetes effects although the mechanisms may differ depending on the type of rice koji consumed.

[Gender-specific aspects of coronary heart disease]

The total number of deaths from cardiovascular diseases (CVD) is greater for women than for men, although the mean age at manifestation of CVD is about 10 years older. However, the annual number of cases treated for CVD in acute hospital settings in men exceeds that of women by 50 %. Remarkable gender differences exist in terms of morphological and physiological conditions (e.g. mean coronary vessel diameter; ability to adapt to protective exercise-induced myocardial hypertrophy), as well as of the frequency and clinical significance of somatic risk factors (e.g. smoking). Female body weight increases after menopause and the body shape assumes a more android fat distribution. Women report higher levels of unspecific and affective symptoms. They suffer more from anxiety and depression than men; however, the secondary impact on CVD onset may be less pronounced. The post-acute CVD course is more complicated in women, mainly because they are older and suffer more from multi-morbidity. Whilst male CVD patients aim for a rapid recovery, physical fitness and an increased life expectancy, female patients seek relief from everyday challenges, the maintenance of their independence and emotional support.

Women's higher health risks in the obesogenic environment: a gender nutrition approach to metabolic dimorphism with predictive, preventive, and personalised medicine

Women's evolution for nurturing and fat accumulation, which historically yielded health and longevity advantages against scarcity, may now be counteracted by increasing risks in the obesogenic environment, recently shown by narrowing gender health gap. Women's differential metabolism/disease risks, i.e. in fat accumulation/distribution, exemplified during puberty/adolescence, suggest gender dimorphism with obesity outcomes. Women's higher body fat percentage than men, even with equal body mass index, may be a better risk predictor. Differential metabolic responses to weight-reduction diets, with women's lower abdominal fat loss, better response to high-protein vs. high-carbohydrate diets, higher risks with sedentariness vs. exercise benefits, and tendency toward delayed manifestation of central obesity, metabolic syndrome, diabetes, cardiovascular disease, and certain cancers until menopause-but accelerated thereafter-suggest a need for differing metabolic and chronological perspectives for prevention/intervention. These perspectives, including women's differential responses to lifestyle changes, strongly support further research with a gender nutrition emphasis within predictive, preventive, and personalized medicine.

Heterogeneity in sex differences in the metabolic syndrome in Dutch white, Surinamese African and South Asian populations

AIM

To determine whether sex differences in the prevalence of the metabolic syndrome and its components differ among different ethnic groups.

METHODS

A random sample of non-institutionalized adults aged 35-60 years in Amsterdam, the Netherlands (white Dutch men n = 242, women n = 244; African-Surinamese men n = 193, women n = 399, Hindustani-Surinamese men n = 149, women n = 186). The metabolic syndrome was defined according to the International Diabetes Federation criteria.

RESULTS

In all ethnic groups, the prevalence of central obesity and reduced HDL cholesterol were higher in women than in men, but the prevalence of elevated blood pressure, fasting glucose and triglycerides were lower in women than in men. However, the magnitude of the differences varied. The sex differences in the prevalence of central obesity and reduced HDL cholesterol were particularly larger in ethnic minority groups, especially in African-Surinamese than in white Dutch. After adjustment for education, smoking, alcohol intake and physical activity, the prevalence of the metabolic syndrome was lower in white Dutch women than in white Dutch men (adjusted prevalence ratio 0.70, 95% CI 0.52-0.94). By contrast, the prevalence of the metabolic syndrome was higher in African-Surinamese women than in African-Surinamese men (adjusted prevalence ratio 1.56, 95% CI 1.12-2.18). Among Hindustani-Surinamese, men and women had a similar prevalence of the metabolic syndrome (adjusted prevalence ratio 1.00, 95% CI 0.76-1.31).

CONCLUSIONS

Our findings suggest different patterns in sex differences in the metabolic syndrome among the ethnic groups. The relatively high prevalence of central obesity in African-Surinamese women may underlie their higher prevalence of the metabolic syndrome. Strategies to improve metabolic profiles among African-Surinamese and white Dutch people need to take sex differences into account.

Changes in metabolic profile and adipoinsular axis in morbidly obese premenopausal females treated with restrictive bariatric surgery

BACKGROUND

The aim of the present study was to evaluate the effects of surgically induced weight loss on the metabolic profile and adipocytokine levels in premenopausal morbidly obese females.

METHODS

Twenty premenopausal morbidly obese (MO) women with a median age of 34 years (range: 24-48 years) and a median body mass index (BMI) of 41.47 kg/m(2) (range: 38.0-56.73 kg/m(2)) were studied (13 women underwent gastric banding and 7 women underwent sleeve gastrectomy). In addition, 20 lean premenopausal women with a median age of 32 years (range: 22-44 years) and a median BMI of 20.0 kg/m(2) (range: 18.5-24.7 kg/m(2)) were also studied. Anthropometric measurements and metabolic parameters were analyzed in each patient, along with changes in leptin, adiponectin, resistin, and interleukin-6 (IL-6) before surgery, 6 months after surgery, and 12 months after surgery. Comparisons with the reference normal-weight subjects were also performed.

RESULTS

Both weight and BMI were found to be significantly decreased postoperatively. A 54.5% loss of excess BMI was observed 12 months after surgery, and was associated with significant improvement in all anthropometric and metabolic parameters. Twelve months after surgery we also observed decreased levels of serum leptin, resistin, and IL-6; increased levels of serum adiponectin; and a remarkable improvement in metabolic syndrome markers. Furthermore, postoperative serum resistin and IL-6 levels were found to reach those of normal-weight volunteers.

CONCLUSIONS

The results of this study suggest that weight loss through restrictive bariatric surgery results in a significant reduction in leptin, resistin, and IL-6 levels, and an increase in adiponectin levels, in addition to improving insulin sensitivity and glucose and lipid homeostasis in young morbidly obese female patients. These changes were significantly correlated with the magnitude of weight loss.

A gender-stratified comparative analysis of various definitions of metabolic syndrome and cardiovascular risk in a multiethnic U.S. population

INTRODUCTION

We sought to evaluate the ability of various metabolic syndrome definitions in predicting primary cardiovascular disease (CVD) outcomes in a vast multiethnic U.S. cohort.

METHODS

This study included 6,814 self-identified men and women aged 45-84 years enrolled in the Multi-Ethnic Study of Atherosclerosis (MESA) study. Gender-stratified analyses were performed to calculate hazard ratios of CVD, stroke, and mortality associated with various metabolic syndrome definitions and their individual constructs.

RESULTS

The hazard ratios [95% confidence interval (CI)] for all-cause CVD in men were 2.90 (2.18-3.85), 2.64 (1.98-3.51), 2.16 (1.62-2.88), 2.56 (1.91-3.44), 1.82 (1.35-2.46), and 2.92 (2.15-3.95) for the National Cholesterol Education Program (NCEP), American Heart Association (AHA), World Health Organization (WHO), International Diabetes Federation (IDF), European Group for the Study of Insulin Resistance (EGIR), and the newly defined consensus criteria. Hazard ratios in women were 2.11 (1.41-3.15), 2.17 (1.45-3.27), 2.04 (1.37-3.06), 1.91 (1.27-2.88), 1.85 (1.23-2.79), and 2.08 (1.37-3.14), respectively. Metabolic syndrome was strongly associated with stroke risk only in males. In men, all constitutive metabolic syndrome components were continuously and strongly associated with CVD. In women, high-density lipoprotein and triglycerides did not appear to be associated with short term CVD risk.

CONCLUSION

We found the newly defined consensus criteria for metabolic syndrome to be similarly predictive of cardiovascular events when compared to existing definitions. Significant gender differences exist in the association between metabolic syndrome, its individual components, and CVD.

Myeloid-specific estrogen receptor alpha deficiency impairs metabolic homeostasis and accelerates atherosclerotic lesion development

ERα is expressed in macrophages and other immune cells known to exert dramatic effects on glucose homeostasis. We investigated the impact of ERα expression on macrophage function to determine whether hematopoietic or myeloid-specific ERα deletion manifests obesity-induced insulin resistance in mice. Indeed, altered plasma adipokine and cytokine levels, glucose intolerance, insulin resistance, and increased adipose tissue mass were observed in animals harboring a hematopoietic or myeloid-specific deletion of ERα. A similar obese phenotype and increased atherosclerotic lesion area was displayed in LDL receptor-KO mice transplanted with ERα(-/-) bone marrow. In isolated macrophages, ERα was necessary for repression of inflammation, maintenance of oxidative metabolism, IL-4-mediated induction of alternative activation, full phagocytic capacity in response to LPS, and oxidized LDL-induced expression of ApoE and Abca1. Furthermore, we identified ERα as a direct regulator of macrophage transglutaminase 2 expression, a multifunctional atheroprotective enzyme. Our findings suggest that diminished ERα expression in hematopoietic/myeloid cells promotes aspects of the metabolic syndrome and accelerates atherosclerosis in female mice.

Fasting plasma glucose and hemoglobin A1c in identifying and predicting diabetes: the strong heart study

OBJECTIVE

To compare fasting plasma glucose (FPG) and HbA(1c) in identifying and predicting type 2 diabetes in a population with high rates of diabetes.

RESEARCH DESIGN AND METHODS

Diabetes was defined as an FPG level ≥ 126 mg/dL or an HbA(1c) level ≥ 6.5%. Data collected from the baseline and second exams (1989-1995) of the Strong Heart Study were used. RESULTS For cases of diabetes identified by FPG ≥ 126 mg/dL, using HbA(1c) ≥ 6.5% at the initial and 4-year follow-up diabetes screenings (or in identifying incident cases in 4 years) among undiagnosed participants left 46% and 59% of cases of diabetes undetected, respectively, whereas for cases identified by HbA(1c) ≥ 6.5%, using FPG ≥ 126 mg/dL left 11% and 59% unidentified, respectively. Age, waist circumference, urinary albumin-to-creatinine ratio, and baseline FPG and HbA(1c) levels were common significant risk factors for incident diabetes defined by either FPG or HbA(1c); triglyceride levels were significant for diabetes defined by HbA(1c) alone, and blood pressure and sibling history of diabetes were significant for diabetes defined by FPG alone. Using both the baseline FPG and HbA(1c) in diabetes prediction identified more people at risk than using either measure alone. CONCLUSIONS Among undiagnosed participants, using HbA(1c) alone in initial diabetes screening identifies fewer cases of diabetes than FPG, and using either FPG or HbA(1c) alone cannot effectively identify diabetes in a 4-year periodic successive diabetes screening or incident cases of diabetes in 4 years. Using both criteria may identify more people at risk. The proposed models using the commonly available clinical measures can be applied to assessing the risk of incident diabetes using either criterion.

Plasma Proteomic Signature in Overweight Girls Closely Correlates with Homeostasis Model Assessment (HOMA), an Objective Measure of Insulin Resistance

Obesity is known to be associated with a large number of long-term morbidities, and while in some cases the relationship of obesity and the consequences is clear (for example, excess weight and lower extremity orthopedic problems) in others the mechanism is not as clear. One common system of categorizing overweight in terms of the likelihood of negative consequences involves using the concept of “metabolic syndrome”. We hypothesized that the development of a plasma protein profile of overweight adolescents with and without the metabolic syndrome might give a more precise and informative picture of the disease process than the current clinical categorization and permit early targeted intervention. For this paper, we used antibody microarrays to analyze the plasma proteome of a group of 15 overweight female adolescent patients. Upon analysis of the proteome, the overweight patients diverged from the nonoverweight female controls. Furthermore, the overweight patients were divided by the analysis into two population clusters, each with distinctive protein expression patterns. Interestingly, the clusters were characterized by differences in insulin resistance, as measured by HOMA. Categorization according to the presence or absence of the metabolic syndrome did not yield such clusters.

Comparison of DEXA and QMR for assessing fat and lean body mass in adult rats

There are several techniques used to measure body composition in experimental models including dual energy X-ray absorptiometry (DEXA) and quantitative magnetic resonance (QMR). DEXA/QMR data have been compared in mice, but have not been compared previously in rats. The goal of this study was to compare DEXA and QMR data in rats. We used rats that varied by sex, diet, and age, in addition we compared dissected samples containing subcutaneous (pelt) or visceral fat (carcass). The data means were compared by focusing on the differences between DEXA/QMR data using a series of scatter plots without assuming that either method is more accurate as suggested by Bland and Altman. DEXA/QMR data did not agree sufficiently in carcass or pelt FM or in pelt LBM. The variation observed within these groups suggests that DEXA and QMR measurements are not comparable. Carcass LBM in young rats did yield comparable data once the data for middle-aged rats was removed. The variation in our data may be a result of different direct and indirect measures that DEXA and QMR technologies use to quantify FM and LBM. DEXA measures FM and estimates fat-free mass. In contrast, QMR uses separate equations of magnetic resonance to measure FM, LBM, total body water and free water. We found that QMR overestimated body mass in our middle-aged rats, and this increased the variation between methods. Our goal was to evaluate the precision of DEXA/QMR data in rats to determine if they agree sufficiently to allow direct comparison of data between methods. However DEXA and QMR did not yield the same estimates of FM or LBM for the majority of our samples.

IGF-binding protein 1 and abdominal obesity in the development of type 2 diabetes in women

OBJECTIVE

Low levels of IGF-binding protein 1 (IGFBP1) are associated with metabolic syndrome and predict diabetes development in men. The aim of this study was to determine the levels of IGFBP1 in women who later develop diabetes, in relation to abdominal obesity, and to compare these levels with those of men.

METHODS

IGFBP1 levels were determined at baseline and after 8 years in a case-control, prospective study of Swedish women aged 35-56 years. Individuals with normal oral glucose tolerance test (OGTT) who developed abnormal glucose regulation (n=240) were pair matched to controls for age and family history of diabetes and also compared to men of the same age (n=355).

RESULTS

Low fasting IGFBP1 and increased waist measurement predicted development of diabetes in women (n=60; odds ratio (OR) 70, 95% confidence interval (CI) 8-661, lowest tertile and OR 27, 95% CI 5-141, highest tertile). In women developing diabetes, baseline IGFBP1 levels were lower than expected for fasting insulin values, were associated with impaired suppression after OGTT and increased during 8 years despite an increase in fasting insulin. All individuals in the highest tertile for waist and with <or=40% suppression of IGFBP1 developed diabetes within 8 years. Circulating IGFBP1 concentrations were higher in women compared to men. Women and men who developed diabetes had a similar degree of abdominal obesity, corrected for height.

CONCLUSIONS

We conclude that low IGFBP1 and elevated waist measurement predict diabetes development and that IGFBP1 production is suppressed by a novel factor(s) in women developing diabetes. Increasing levels of IGFBP1 during the emergence of diabetes in men and women suggest the emergence of hepatic insulin resistance.

Variations in tryptophan hydroxylase 2 linked to decreased serotonergic activity are associated with elevated risk for metabolic syndrome in depression

Major depression and the metabolic syndrome (MetS) are interacting clinical conditions influenced by genetic susceptibility. For both disorders, impaired serotonergic neurotransmission in specific brain areas has been suggested. This led us to investigate whether variants in the gene coding for tryptophan hydroxylase 2 (TPH2), the brain-specific and rate-limiting enzyme for serotonin biosynthesis, might be predictive for an increased liability for the development of MetS in depressed patients. In a case-control study consisting of 988 patients with recurrent unipolar depression (RUD) and 1023 psychiatric healthy controls, MetS components were ascertained according to the International Diabetes Foundation criteria. A total of 41 single nucleotide polymorphisms fully covering the TPH2 gene region were genotyped in stage 1 (300 patients/300 controls), resulting in significant genetic associations of polymorphisms located in exon 7 and intron 8 of TPH2 and the occurrence of MetS in depressed patients after correction for age, gender and multiple testing (51 RUD-MetS/179 RUD-non-MetS). We were able to confirm the significant association of rs17110690 in stage 2 (688 patients/723 controls; 110 RUD-MetS/549 RUD-non-MetS) and to link risk-genotypes and risk-haplotypes for MetS to lower TPH2 mRNA expression and to lower 5-hydroxyindoleacetic acid levels in cerebrospinal fluid previously reported in functional studies. Our findings suggest that TPH2 polymorphisms characterize a subgroup of depressed patients who are especially prone to develop metabolic disorders induced by a genotype-dependent impairment of serotonergic neurotransmission. Identifying depressed patients at high risk for MetS using genetic variants could have direct clinical impact on individualized disease management and prevention strategies.

Adults with mood disorders have an increased risk profile for cardiovascular disease within the first 2 years of treatment

OBJECTIVES

People with bipolar disorder (BD) and major depressive disorder (MDD) are at risk for premature death from various physical illnesses. A large component of this risk may be accounted for by an elevated risk of metabolic syndrome (MeS) and coronary heart disease (CHD). The objective of our study was to examine patients' physical health prior to first treatment and over 2 years of follow-up.

METHODS

Ten-year risk for CHD and incidence of MeS were calculated for newly diagnosed patients with MDD (n = 30) and BD (n = 24) at baseline and over a 2-year follow-up. Age and sex-matched control subjects were obtained from the National Health and Nutrition Examination Survey III dataset.

RESULTS

At baseline, 11.2% of patients met diagnostic criteria for MeS and this increased to 16.8% at follow-up. Women had higher rates of MeS but rates were similar across diagnosis. There was a significant increase within all MeS criteria. The 10-year CHD risk was low for patients at baseline and follow-up but increased across the follow-up period. Changes in CHD and MeS risk were not associated with a specific type of pharmacotherapy, as all medication classes appeared to increase risk.

CONCLUSION

Prior to treatment, MeS and CHD risk rates for patients were similar to the general population, but their risk of CHD increased appreciably.

Metabolic impact of sex hormones on obesity

Obesity and its associated health disorders and costs are increasing. Men and post-menopausal women have greater risk of developing complications of obesity than younger women. Within the brain, the hypothalamus is an important regulator of energy homeostasis. Two of its sub-areas, the ventrolateral portion of the ventral medial nucleus (VL VMN) and the arcuate (ARC) respond to hormones and other signals to control energy intake and expenditure. When large lesions are made in the hypothalamus which includes both the VL VMN and the ARC, animals eat more, have reduced energy expenditure, and become obese. The ARC and the VL VMN, in addition to other regions in the hypothalamus, have been demonstrated to contain estrogen receptors. There are two estrogen receptors, estrogen receptor alpha (ERalpha) and estrogen receptor beta (ERbeta). We and others have previously demonstrated that activation of ERalpha by estrogens reduces food intake and increases body weight. This review focuses on the relative contribution of activation of ERalpha by estrogens in the ARC and the VL VMN in the regulation of food intake and body weight. Additionally, estrogen receptors have been found in many peripheral tissues including adipose tissue. Estrogens are thought to have direct effects on adipose tissue and estrogens may provide anti-inflammatory properties both in the periphery and the in the central nervous system (CNS) which may protect women from diseases associated with inflammation. Understanding the mechanisms by which estrogens regulate body weight and inflammation will assist in determining potential therapeutic agents for menopausal women to decrease the propensity of diseases associated with obesity.

Impaired oxidative metabolism and inflammation are associated with insulin resistance in ERalpha-deficient mice

Impaired estrogen action is associated with the metabolic syndrome in humans. We sought to determine whether impaired estrogen action in female C57Bl6 mice, produced by whole body Esr1 ablation, could recapitulate aspects of this syndrome, including inflammation, insulin resistance, and obesity. Indeed, we found that global knockout (KO) of the estrogen receptor (ER)alpha leads to reduced oxygen uptake and caloric expenditure compared with wild-type (WT) mice. In addition, fasting insulin, leptin, and PAI-1 levels were markedly elevated, whereas adiponectin levels were reduced in normal chow-fed KO. Furthermore, ERalpha-KO mice exhibited impaired glucose tolerance and marked skeletal muscle insulin resistance that was accompanied by the accumulation of bioactive lipid intermediates, inflammation, and diminished PPARalpha, PPARdelta, and UCP2 transcript levels. Although the relative glucose intolerance and insulin resistance phenotype in KO mice became more severe with high-fat feeding, WT mice were refractory to these dietary-induced effects, and this protection coincided with a marked increase in circulating adiponectin and heat shock protein 72 levels in muscle, liver, and fat. These data indicate that ERalpha is critical for the maintenance of whole body insulin action and protection against tissue inflammation during both normal chow and high-fat feeding.

Prevalence of metabolic syndrome in an adult urban population of the west of Iran

Objectives. We determine the prevalence of the metabolic syndrome in an urban population of Zanjan, a province located to the west of Tehran. Methods. Randomly selected adults >20 years were studied using stratified sampling. Target study sample was 2941 (1396 males and 1545 females). Metabolic syndrome was diagnosed using Adult Treatment Panel-III (ATP-III) guidelines when any three of the following were present: central obesity, raised triglycerides ≥150 mg/dl, low high-density lipoprotein (HDL) cholesterol, blood pressure ≥ 130/ ≥ 85 mm Hg, and diabetes or fasting plasma glucose (FPG) ≥ 100 mg/dl. Results. Metabolic syndrome was present in 697 (23.7%) subjects (CI 95%:22%–25%, P = .001), prevalence was 23.1% in men and 24.4% in women (P : .4). The prevalence increased from 7.5% in the population younger than 30 y to 45.6% in ages more than 50 years. Low HDL was the most common metabolic abnormality in both sexes. Most of those with metabolic syndrome had three components of the syndrome (75.6%), 170 subjects (24.4%) had four and none had five components simultaneously. The prevalence of obesity (BMI ≥ 30 kg/m²), hypercholesterolemia (≥200 mg/dl) and high LDL cholesterol (≥130 mg/dl) was greater in the metabolic syndrome group than normal subjects (P = .00). Conclusions. There is a high prevalence of metabolic syndrome in this urban population of the northern west of Iran. Focus of cardiovascular prevention should be undertaken in this area.

Menopause, the metabolic syndrome, and mind-body therapies

Cardiovascular disease risk rises sharply with menopause, likely due to the coincident increase in insulin resistance and related atherogenic changes that together comprise the metabolic or insulin resistance syndrome, a cluster of metabolic and hemodynamic abnormalities strongly implicated in the pathogenesis and progression of cardiovascular disease. A growing body of research suggests that traditional mind-body practices such as yoga, tai chi, and qigong may offer safe and cost-effective strategies for reducing insulin resistance syndrome-related risk factors for cardiovascular disease in older populations, including postmenopausal women. Current evidence suggests that these practices may reduce insulin resistance and related physiological risk factors for cardiovascular disease; improve mood, well-being, and sleep; decrease sympathetic activation; and enhance cardiovagal function. However, additional rigorous studies are needed to confirm existing findings and to examine long-term effects on cardiovascular health.

Gender aspects of the role of the metabolic syndrome as a risk factor for cardiovascular disease

BACKGROUND

The interaction of the risk factors of abdominal obesity, disturbed glucose homeostasis, dyslipidemia, and hypertension is believed to represent a distinct entity, termed the metabolic syndrome (MetS), that leads to a greater increase in cardiovascular risk than does the sum of its components.

OBJECTIVE

We reviewed currently available information regarding gender differences in the role of the MetS as a risk factor for cardiovascular disease (CVD).

METHODS

Using the search terms women, men, sex, gender, sex differences, and gender differences in combination with the metabolic syndrome, we conducted a systematic review of the available literature on sex differences in the MetS. The National Institutes of Health, PubMed, and MEDLINE databases were searched retrospectively from 2007 to 1987. Reference lists of identified articles were also used as a source, and articles were not restricted to the English language.

RESULTS

In recent years, the MetS has been more prevalent in men than in women but has risen particularly in young women, where it is mainly driven by obesity. Diagnostic criteria for the MetS vary for the cutoff points and definition of its components in a gender-specific manner. Based on the definition of impaired glucose homeostasis and pathologic abdominal circumference or waist/hip ratio, more or fewer women are included. Glucose and lipid metabolism are directly modulated by estrogen and testosterone, with a lack of estrogen or a relative increase in testosterone inducing insulin resistance and a proatherogenic lipid profile. Hypertension is a strong risk factor in both sexes, but the prevalence of hypertension increases more rapidly in aging women than in men. Menopause and polycystic ovary syndrome contribute to the development of MetS by the direct effects of sex hormones. Some components of the MetS (eg, diabetes and hypertension) carry a greater risk for CVD in women.

CONCLUSIONS

Future gender-related clinical and research activities should focus on the identification of sex- and gender-specific criteria for risk management in patients with the MetS. We propose small, focused, mechanistic studies on sex-specific surrogate end points and sex-specific studies in animal models for diabetes and aging.

Prevalence of metabolic syndrome in a rural area of Brazil

CONTEXT AND OBJECTIVE

Metabolic syndrome (MS) is recognized worldwide as an important public health concern. However, little information is available for rural populations in Brazil. The aim was to determine the prevalence and risk factors associated with MS in a rural village in Brazil in 2004.

DESIGN AND SETTING

Cross-sectional population-based study, in Virgem das Graças, a rural community in the Jequitinhonha Valley, State of Minas Gerais.

METHODS

MS was the dependent variable, defined as any three of these risk factors: arterial hypertension, high glucose or triglyceride concentrations, low high-density lipoprotein cholesterol and abdominal obesity. MS prevalence, according to selected socioeconomic and demographic variables (age, skin color, marital status, schooling and smoking habits), was determined in 251 subjects aged 20-88 years. Multivariate logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals.

RESULTS

MS prevalence was 21.6% (7.7% for men and 33.6% for women); the age-adjusted prevalence was 19.0%. The highest prevalences were observed for women > 60 years of age (52.9%) and women with body mass index (BMI) >or= 25 kg/m(2) (64%). Age, sex and BMI were associated risk factors for MS, while skin color was only significantly associated with MS for women. The models were adjusted for age, smoking habits, marital status, skin color and schooling.

CONCLUSIONS

BMI and age were independently associated factors for MS in this rural community. These findings provide important evidence on the prevalence of MS as a public health problem, particularly for women and overweight individuals.

Searching for polycystic ovary syndrome in postmenopausal women: evidence of a dose-effect association with prevalent cardiovascular disease

OBJECTIVE

To test the hypothesis that polycystic ovary syndrome (PCOS) is associated with an increased risk of atherosclerotic cardiovascular disease (CVD) in older postmenopausal women.

DESIGN

Cross-sectional study of community-dwelling non-estrogen-using postmenopausal-white women (N=713; mean+/-SD age, 73.8+/-7.9 years; mean body mass index, 24.0+/-3.5 kg/m) participating in the Rancho Bernardo Study. A putative PCOS phenotype was defined as the presence of three or more of the following features: (1) recalled history of irregular menses, (2) symptomatic premenopausal hyperandrogenism or biochemical evidence of current biochemical hyperandrogenism, (3) history of infertility or miscarriage, (4) central obesity, or (5) insulin resistance. Atherosclerotic CVD was determined from clinical history, electrocardiography, and structured interviews using validated techniques. The analysis was stratified by diabetes status, ascertained from medical history or 75-g oral glucose tolerance tests.

RESULTS

The PCOS phenotype was present in 9.3% of the entire cohort and 5.8% of nondiabetic women. The prevalence of CVD was similar between women with the phenotype and unaffected women (27.3% vs 24.4%). Among women with intact ovaries and no diabetes, there was a stepwise graded association between an increasing number of features of the PCOS phenotype (ie, none to three or more) and prevalent CVD (P=0.02). A similar association was also observed for coronary heart disease alone (P=0.03).

CONCLUSIONS

Among nondiabetic postmenopausal women with intact ovaries, prevalent atherosclerotic CVD is associated with features of a putative PCOS phenotype. This finding supports the thesis that PCOS increases the risk of atherosclerotic CVD after menopause.

Glucocorticoids, chronic stress, and obesity

Glucocorticoids either inhibit or sensitize stress-induced activity in the hypothalamo-pituitary-adrenal (HPA) axis, depending on time after their administration, the concentration of the steroids, and whether there is a concurrent stressor input. When there are high glucocorticoids together with a chronic stressor, the steroids act in brain in a feed-forward fashion to recruit a stress-response network that biases ongoing autonomic, neuroendocrine, and behavioral outflow as well as responses to novel stressors. We review evidence for the role of glucocorticoids in activating the central stress-response network, and for mediation of this network by corticotropin-releasing factor (CRF). We briefly review the effects of CRF and its receptor antagonists on motor outflows in rodents, and examine the effects of glucocorticoids and CRF on monoaminergic neurons in brain. Corticosteroids stimulate behaviors that are mediated by dopaminergic mesolimbic "reward" pathways, and increase palatable feeding in rats. Moreover, in the absence of corticosteroids, the typical deficits in adrenalectomized rats are normalized by providing sucrose solutions to drink, suggesting that there is, in addition to the feed-forward action of glucocorticoids on brain, also a feedback action that is based on metabolic well being. Finally, we briefly discuss the problems with this network that normally serves to aid in responses to chronic stress, in our current overindulged, and underexercised society.

Whole-Grain Diets Reduce Blood Pressure in Mildly Hypercholesterolemic Men and Women

The objective of this study was to compare the effects on blood pressure of predominantly insoluble fiber (whole wheat and brown rice) and soluble fiber (barley) in a whole-grain diet. Subjects (seven men, nine premenopausal women, and nine postmenopausal women) consumed a controlled Step I diet for 2 weeks; then about 20% of energy was replaced with whole wheat/brown rice, barley, or half wheat-rice/half barley, for 5 weeks each. Blood pressure was determined weekly and weight daily before breakfast. Urinary excretions of minerals that might affect blood pressure and urea nitrogen were determined each period. Systolic pressure was lower after the wheat/rice and half-and-half diets. Diastolic and mean arterial pressures were reduced by all whole-grain diets. No differences were observed in urinary measurements. In a healthful diet, increasing whole-grain foods, whether high in soluble or insoluble fiber, can reduce blood pressure and may help to control weight.

The metabolic syndrome: prevalence and association to leisure-time and work-related physical activity in 60-year-old men and women

BACKGROUND AND AIM

This study examined the prevalence of the metabolic syndrome and its association to lifestyle factors in 60-year-old men and women, with special emphasis on physical activity (PA).

METHODS AND RESULTS

Every third 60-year-old man and woman in the Stockholm County, Sweden, was invited to a survey of cardiovascular risk factors. Seventy-seven percent of the sample, 4228 individuals, agreed to participate (2036 men and 2192 women). Participants underwent physical examination and laboratory tests, and completed a questionnaire. After excluding 364 subjects suffering from cardiovascular disease and/or cancer, the prevalence of the metabolic syndrome was 24% and 19% in men and women, respectively. The adjusted odds ratio for having the metabolic syndrome in the high leisure-time PA group was 0.33 (95% confidence interval: 0.22-0.51) using the low leisure-time PA group as reference. However, no such inverse association was noted for work-related PA.

CONCLUSIONS

This cross-sectional survey of 60-year-old men and women demonstrates a high prevalence of the metabolic syndrome. The robust inverse dose-response relationship between leisure-time PA and the metabolic syndrome emphasises the role of PA in the prevention and treatment of the metabolic syndrome.

The metabolic syndrome in women: a growing problem for cardiac risk

The risk of developing cardiovascular disease has recently been associated with a set of metabolic and physiological risk factors that include abdominal obesity, atherogenic dyslipidemia, hypertension, and elevated plasma glucose. The term most commonly used to describe this conglomeration of risk factors is the metabolic syndrome. Coronary heart disease risk is tripled in those individuals with this syndrome. Primary treatment focuses on weight reduction and physical activity to reduce risk factors and prevent the progression to cardiovascular disease. This article will review the definition, prevalence, pathogenesis, and treatment of the metabolic syndrome in women and will discuss the role of polycystic ovarian syndrome in relation to the metabolic syndrome.

Anthropometric features and cardiovascular risk in young Latin Americans with type 2 diabetes mellitus

OBJECTIVE

The purpose of this study is to compare score systems used to estimate the risk for cardiovascular disease (CVD) in young patients with poorly controlled type 2 diabetes.

METHODS

Fifty-seven Latin American patients with type 2 diabetes, between the ages 18 and 45 years, were screened to participate in a clinical research study evaluating the effects of intensive insulin therapy on both traditional and nontraditional CVD risk factors. All women were premenopausal and had regular menstrual periods. Baseline reviews of cardiovascular (CV) risk scores, personal history, physical examination, and laboratory screening were performed. The Framingham Study Score system and the presence of features of the metabolic syndrome (MSyn) were recorded and compared.

RESULTS

Both genders had a comparable number of features of the MSyn, whereas according to the Framingham Score System, men had a slightly higher risk of CVD.

CONCLUSIONS

The Framingham Score system is not an accurate device to estimate risk of CVD in premenopausal women with type 2 diabetes mellitus, who otherwise have a multiple features of the MSyn. If used to estimate risk of CVD, the Framingham score system could underestimate the risk of CVD in both young men and women with type 2 diabetes mellitus.

Gender differences in the metabolic syndrome and their role for cardiovascular disease

Women live longer than men and develop cardiovascular disease (CVD) at an older age. The metabolic syndrome represents a major risk factor for the development of CVD, and gender differences in this syndrome may contribute to gender differences in CVD. In recent years, the metabolic syndrome has been more prevalent in men than in women. Prevalence is increasing and this increase has been steeper in women, particularly in young women, during the last decade. The contributions of the different components of the metabolic syndrome differ between genders and in different countries. In a recent survey in Germany, 40% of the adult population had been diagnosed with disturbed glucose tolerance or type 2 diabetes. Undiagnosed diabetes was more frequent in men than in women, and risk factors for undiagnosed diabetes differed between the sexes. Worldwide, in individuals with impaired glucose tolerance, impaired fasting glucose was observed more frequently in men, whereas impaired glucose tolerance occurred relatively more often in women. Lipid accumulation patterns differ between women and men. Premenopausal women more frequently develop peripheral obesity with subcutaneous fat accumulation, whereas men and postmenopausal women are more prone to central or android obesity. In particular, android obesity is associated with increased cardiovascular mortality and the development of type 2 diabetes. Visceral adipocytes differ from peripheral adipocytes in their lipolytic activity and their response to insulin, adrenergic and angiotensin stimulation and sex hormones. Visceral fat is a major source of circulating free fatty acids and cytokines, which are directly delivered via the portal vein to the liver inducing insulin resistance and an atherogenic lipid profile. Inflammation increases cardiovascular risk particularly in women. A relatively greater increase in cardiovascular risk by the appearance of diabetes in women has been reported in many studies.Thus, the presently available data suggest that the pathophysiology of the metabolic syndrome and its contribution to the relative risk of cardiovascular events and heart failure show gender differences, which might be of potential relevance for prevention, diagnostics, and therapy of the syndrome.

Association of increased body mass index and impaired endothelial function among Hispanic women

We tested the hypothesis that an increased body mass index was similarly associated with impaired endothelial function as measured by flow-mediated dilation in a high-risk, Hispanic population of men and women living in northern Manhattan. The association of flow-mediated dilation and body mass index was significant in women (beta -0.16 +/- 0.04, p <0.0001) but not in men (beta -0.02 +/- 0.06, p = 0.72). This is the first study to demonstrate a gender-specific difference in endothelial function associated with body mass index.

Underreporting of Pregnancy-Related Mortality in the United States and Europe

OBJECTIVE

Available maternal mortality statistics do not allow valid international comparisons. Our objective was to uniformly measure underreporting of mortality from pregnancy in official statistics from selected regions within the U.S. and Europe, and to provide comparable revised profiles of pregnancy-related mortality.

METHODS

We developed a standardized enhanced method to uniformly identify and classify pregnancy-associated deaths from 2 U.S. states, Massachusetts and North Carolina, and 2 European countries, Finland and France, for the years 1999-2000. Identification method included the use of all data available from the death certificate as well as computerized linkage of births and deaths registers. All cases were reviewed and classified by an international panel of experts.

RESULTS

Four-hundred-and-four pregnancy-associated deaths were identified and reviewed. Underestimation of mortality causally related to pregnancy based on International Classification of Diseases cause-of-death codes alone varied from 22% in France to 93% in Massachusetts. Underreporting was greater in the regions with lower initial maternal mortality ratios. The distribution of causes of pregnancy-related mortality was specific to each region. The leading causes of death were cardiovascular conditions in Massachusetts; hemorrhage, pregnancy-induced hypertension, and peripartum cardiomyopathy in North Carolina; noncardiovascular medical conditions in Finland; and hemorrhage in France.

CONCLUSION

This study shows the limitations of maternal mortality statistics based on International Classification of Diseases cause-of-death codes alone. Linkage of births and deaths registers should routinely be used in the ascertainment of pregnancy-related deaths. In addition, extension of the definition of a maternal death should be considered. Beyond pregnancy-related mortality ratios, considering the specific distribution of causes-of-death is important to define prevention strategies.

Comparison of Hormone and Glucose Responses of Overweight Women to Barley and Oats

OBJECTIVE

To determine the effect of particle size (flour vs. flakes) on glycemic responses after oats and barley (Prowashonupana cultivar), which contain high amounts of soluble fiber, are consumed by overweight women.

DESIGN

Ten women, average age 50 years and body mass index 30, consumed glucose (1 g/kg body weight) and four test meals (1 g carbohydrate/kg body weight; 2/3 of the carbohydrate from oat flour, oatmeal, barley flour, or barley flakes and 1/3 from pudding) in a Latin square design after consuming controlled diets for 2 days. Blood samples were collected at fasting and periodically after each meal.

RESULTS

Peak glucose and insulin levels after barley were significantly lower than those after glucose or oats. Glucose areas under the curve (AUCs) after test meals compared with AUCs after glucose were reduced after both oats and barley (29-36% by oats and 59-65% by barley) (p < 0.002). Insulin AUCs after test meals compared with glucose AUCs were significantly reduced only by barley (44-56%) (p < 0.005). Indexes for insulin resistance (HOMA, MFFM, Cederholm) after the oat and barley meals were not different from indexes after the glucose meal. Glucagon and leptin responses did not significantly differ for the carbohydrates tested.

CONCLUSIONS

Particle size of the oats or barley had little effect on the glycemic responses. Both oat and barley meals reduced glycemic responses; the high soluble fiber content of this barley appeared to be a factor in the greater reduction observed.

Enlarged Waist Combined With Elevated Triglycerides Is a Strong Predictor of Accelerated Atherogenesis and Related Cardiovascular Mortality in Postmenopausal Women

BACKGROUND

Upward trends of obesity urge more effective identification of those at cardiovascular risk. A simple dichotomous indicator, enlarged waist (> or =88 cm) combined with elevated triglycerides (> or =1.45 mmol/L) (EWET), was shown to offer advantages in identifying individuals with atherogenic "lipid overaccumulation" compared with other indicators, including the metabolic syndrome defined by the National Cholesterol Education Program (MS-NCEP). Whether EWET offers superior disease and event prediction in postmenopausal women, however, remains unknown.

METHODS AND RESULTS

A community-based sample of 557 women (48 to 76 years of age) were followed up for 8.5+/-0.3 years to assess the utility of EWET and MS-NCEP in estimating the risk of all-cause and cardiovascular mortality and the annual progression rate of aortic calcification. At baseline, 15.8% of women had EWET and 17.6% had MS-NCEP. All-cause mortality and cardiovascular mortality were increased in carriers of the dichotomous indicators (P<0.001). After adjustment for age, smoking, and LDL cholesterol, presence of EWET was associated with a 4.7-fold (95% CI, 2.2 to 9.8; P<0.001) increased risk and presence of MS-NCEP was associated with a 3.2-fold (95% CI, 1.5 to 6.5; P<0.001) increased risk for fatal cardiovascular events. Exclusion of women with prevalent diabetes did not change these trends; respective hazard ratios were 4.2 (95% CI, 1.9 to 9.3; P<0.001) and 2.5 (95% CI, 1.1 to 5.5; P<0.05). Among those who were discordant for EWET and MS-NCEP at baseline, those who had EWET alone (n=21) had a higher annual progression rate of aortic calcification compared with those who had MS-NCEP alone (n=31; P<0.05).

CONCLUSIONS

The combined presence of EWET may be the best indicator of cardiovascular risk in postmenopausal women. Other components of the MS-NCEP add little medical value to screening in general practices.

Inflammation, insulin resistance, and obesity

Obesity, in particular visceral obesity, has strong associations with cardiovascular disease and is related to many factors that are constituents of the metabolic syndrome. Increasing evidence suggests that features of the metabolic syndrome, including visceral obesity, are associated with a low-grade inflammatory state. Indeed, visceral fat is a source of several molecules, such as leptin, adiponectin, tumor necrosis factor-alpha, and interleukin 6, that are collectively called adipokines. All of them may induce a proinflammatory state and oxidative damage, leading to initiation and progression of atherosclerosis. Reduced-energy diets might represent an effective and healthful approach for long-term weight loss in patients with metabolic syndrome by reducing the underlying inflammatory condition.

Consumption of a high-fat diet alters the homeostatic regulation of energy balance

Humans in many countries are currently experiencing what has been called an epidemic of obesity. That is, the average body weight (and amount of fat stored in the body) is increasing over years, carrying with it a multitude of associated medical, psychological, and economic problems. While there is no shortage of possible causes of this epidemic, increased availability and consumption of high-fat (HF), calorically dense and generally quite palatable food is often touted as a likely culprit. In order to better assess the impact of consuming a diet with those qualities, we have developed a well-controlled animal model in which the effects of chronic consumption of a high-fat diet can be dissociated from those of becoming obese per se. Long-Evans rats are fed one of two semipurified pelleted diets, a HF diet that contains 20% fat by weight and a low-fat (LF) diet that contains 4% fat by weight. Pair-fed animals consume the HF diet but are limited to the daily caloric intake of LF rats. Another group receives pelleted chow. Relative to animals consuming diets low in fat, HF animals weigh more, have more carcass fat, are hyperinsulinemic and hyperleptinemic, and are insulin resistant. HF-fed animals, independent of whether they become obese or not, also have central insulin and MTII insensitivity. Finally, HF rats have a down-regulated hypothalamic apo A-IV system that could contribute to their hyperphagia.

New aspects in the pathogenesis of diabetic atherothrombosis

Diabetes mellitus is increasing worldwide, resulting from the interaction of obesity, inflammation, and hyperglycemia. Activated immunity and cytokine production lead to insulin resistance and other components of the metabolic syndrome, establishing the link between diabetes and atherosclerosis. Hyperglycemia-induced endothelial dysfunction is mediated by increased oxidative stress, a promoter of adventitial inflammation and vasa vasorum neovascularization in experimental models of diabetic atherosclerosis. Recent studies have documented increased inflammation, neovascularization, and intraplaque hemorrhage in human diabetic atherosclerosis. This inflammatory microangiopathic process is independently associated with plaque rupture, leading to coronary thrombosis. Tissue factor, the most potent trigger of the coagulation cascade, is increased in diabetic patients with poor glycemic control. Circulating tissue factor microparticles are also associated with apoptosis of plaque macrophages, closing the link among inflammation, plaque rupture, and blood thrombogenicity. High-density lipoproteins, responsible for free cholesterol removal, are reduced in patients with insulin resistance and diabetes. High-density lipoprotein therapy leads to a significant decrease in plaque macrophages and increase in smooth-muscle cells. These beneficial effects may be responsible for coronary plaque stabilization in patients treated with recombinant Apolipoprotein A-I Milano/phospholipid complex. Finally, peroxisomal proliferator-activated receptors (PPARs) are now considered the nuclear transcriptional regulators of atherosclerosis. Three subfamilies, including PPAR-alpha, -delta, and -gamma, have been identified with crucial roles in lipid metabolism, plaque inflammation, expression of adhesion molecules and cytokines, and regulation of matrix metalloproteinases. Multiple experimental studies have documented plaque stabilization with PPAR-gamma agonists, a group of medications holding great promise in the treatment of diabetes atherosclerosis.

Novel associations between bioavailable estradiol and adipokines in elderly women with different phenotypes of obesity: implications for atherogenesis

BACKGROUND

Peripheral adiposity confers protection against diabetes and atherosclerosis in elderly women. The underlying mechanisms, however, remain to be elucidated.

METHODS AND RESULTS

On the basis on dual-energy X-ray absorptiometry measurements of central fat mass (CFM) and peripheral fat mass (PFM), we identified 290 elderly women with distinct forms of body fat distribution (lean, peripheral obesity, central obesity, or general obesity). Study parameters were plasma tumor necrosis factor-alpha, interleukin (IL)-6, adiponectin, estradiol, sex hormone-binding globulin, insulin resistance, and aortic calcification, graded on lateral radiography. In peripherally and generally obese women, plasma estradiol and insulin resistance were significantly lower, whereas sex hormone-binding globulin and adiponectin were significantly higher compared with centrally obese women independent of age, body mass index, total fat mass, and smoking habits (all P<0.05). After adjustment for these confounders, IL-6 in centrally obese women was comparable with that seen in generally obese (similar high CFM%) but significantly higher than in peripherally obese women and lean women (low CFM%). Atherosclerosis was less severe in generally obese (2.5+/-0.3) compared with centrally obese women (5.0+/-0.7, P=0.001). In multiple regression analysis, total fat mass, body fat distribution, insulin resistance, estradiol, current smoking, treated hyperlipidemia, and treated hypertension contributed independently to the variation of aortic calcification (R=0.55, SEE=3.60, P<0.001).

CONCLUSIONS

Abundant presence of PFM in generally obese women is associated with increased plasma adiponectin and higher insulin sensitivity, which could explain the apparent protection against the atherogenic effects of IL-6 derived from CFM. Low peripheral exposure to estradiol appears to be a sine qua non of maintained adiponectin secretion from PFM.