Upper body fat predicts metabolic syndrome similarly in men and women

Influence of Home Language Use on the Association Between Parent Education and Child Adiposity in Latino Families

BACKGROUND

Parent education and language use are associated with child obesity, but the impact of their interaction is less known. This study assessed whether parent education was associated with child adiposity and if this association was moderated by home language use in Latino families.

METHODS

Participants (n = 415) were Latino families from the Long Beach area. Demographic data were obtained by self-report parent surveys, and children's body size was objectively assessed via bioelectric impedance. Independent t-tests and hierarchical linear regressions were performed on baseline data from a larger intervention study.

RESULTS

In the overall sample, parent education and child body mass index (BMI) percentile were not related (p = .050). However, stratification by home language use revealed that parent education was inversely associated with child BMI percentile among those whose primary home language was Spanish (p = .049), but not English/bilingual homes (p = .296). There were no significant associations with child percent body fat.

CONCLUSION

Higher education was associated with a lower BMI percentile only in Spanish-speaking homes. Research to understand how home language influences this relationship is warranted, particularly as it relates to a subset of education and health literacy. Significant results with BMI percentile but not percent body fat highlight the fact that these distinct markers of obesity are not interchangeable.

Omega-3 and omega-6 fatty acids: Inverse association with body fat percentage and obesity risk

To investigate the association between the omega-6 and omega-3 intakes and body fat percentage (BF%), and the risk of obesity, we conducted a cross-sectional analysis of data from the National Health and Nutrition Examination Survey (NHANES). We hypothesized that increasing omega-3 or omega-6 intakes could reduce BF% and, consequently, the risk of obesity. Therefore, we utilized data from NHANES collected between 2011 and 2018, focusing on adults aged 20 to 59 years. Omega-3 and omega-6 intakes were categorized into tertiles, and weighted multivariate linear regression models were used to assess their association with BF%. The dose-response relationship was further analyzed using a restricted cubic spline (RCS) function. A total of 6372 adults were included in the study. Both omega-6 and omega-3 intakes were significantly lower in the obese group compared to the non-obese group (P< .05). Multivariable adjusted models demonstrated a significantly lower BF% among participants in the highest tertile of the omega-3 (β = -0.90, 95% CI: -1.25, -0.55, P< .001) and omega-6 group (β = -0.82, 95% CI :-1.17, -0.47, P< .001). An inverse correlation between the omega-3 and omega-6 intakes and BF% was observed (P< .05), consistent across both genders. Restricted cubic splines (RCS) analysis revealed a linear relationship between the omega-3 and omega-6 intakes and BF%, consistent across gender subgroups (P for nonlinear > .05). These findings suggest that higher omega-3 and omega-6 intakes may contribute to reduced obesity risk by lowering BF%. Further longitudinal studies are warranted to validate these results.

Multilevel Mediators on the Associations of Neighborhood Social Environmental Factors and Severity of Metabolic Syndrome: The Jackson Heart Study

BACKGROUND

Neighborhood characteristics serve as risk factors for metabolic syndrome (MetS). However, the intermediary factors linking this relationship remain understudied. Thus, we investigated the sex-specific mediating role of C-reactive protein, physical activity (PA), and perceived stress in the associations of perceived neighborhood social environment (PNSE) with MetS severity among Black adults.

METHODS AND RESULTS

This cross-sectional study included 3185 adults (64% women) from exam 1 (2000-2004) of the Jackson Heart Study. MetS severity Z scores were calculated based on the Adult Treatment Panel III criteria formula. PNSE included neighborhood violence, problems, and social cohesion. Men and women were analyzed separately. A bootstrap resampling technique with 95% bias-corrected CI (95% BC CI) was used to evaluate whether C-reactive protein, PA, and perceived stress mediated the association between each PNSE and MetS severity, adjusting for covariates. All PNSE factors were directly related to MetS severity in women but not in men. In women, neighborhood problems were indirectly associated with MetS severity mediated through PA (β=0.02 [95% BC CI, 0.00-0.05]). In men, neighborhood violence, problems, and social cohesion were indirectly associated with MetS severity mediated through PA (β=0.05 [95% BC CI, 0.01-0.10]; β=0.03 [95% BC CI, 0.00-0.06]; and β=-0.04 [95% BC CI, -0.09 to -0.01], respectively). Neither C-reactive protein nor perceived stress mediated such associations in either women or men.

CONCLUSIONS

All PNSEs (violence, problems, and social cohesion) were directly related to MetS severity in women only. PA mediated the relationship between each PNSE and MetS in a sex-specific manner. Efforts focusing on local conditions are needed to better understand why such disparities exist for at-risk minoritized groups.

Obesity and Cancer: A Current Overview of Epidemiology, Pathogenesis, Outcomes, and Management

BACKGROUND

Obesity or excess body fat is a major global health challenge that has not only been associated with diabetes mellitus and cardiovascular disease but is also a major risk factor for the development of and mortality related to a subgroup of cancer. This review focuses on epidemiology, the relationship between obesity and the risk associated with the development and recurrence of cancer and the management of obesity.

METHODS

A literature search using PubMed and Google Scholar was performed and the keywords 'obesity' and cancer' were used. The search was limited to research papers published in English prior to September 2022 and focused on studies that investigated epidemiology, the pathogenesis of cancer, cancer incidence and the risk of recurrence, and the management of obesity.

RESULTS

About 4-8% of all cancers are attributed to obesity. Obesity is a risk factor for several major cancers, including post-menopausal breast, colorectal, endometrial, kidney, esophageal, pancreatic, liver, and gallbladder cancer. Excess body fat results in an approximately 17% increased risk of cancer-specific mortality. The relationship between obesity and the risk associated with the development of cancer and its recurrence is not fully understood and involves altered fatty acid metabolism, extracellular matrix remodeling, the secretion of adipokines and anabolic and sex hormones, immune dysregulation, and chronic inflammation. Obesity may also increase treatment-related adverse effects and influence treatment decisions regarding specific types of cancer therapy. Structured exercise in combination with dietary support and behavior therapy are effective interventions. Treatment with glucagon-like peptide-1 analogues and bariatric surgery result in more rapid weight loss and can be considered in selected cancer survivors.

CONCLUSIONS

Obesity increases cancer risk and mortality. Weight-reducing strategies in obesity-associated cancers are important interventions as a key component of cancer care. Future studies are warranted to further elucidate the complex relationship between obesity and cancer with the identification of targets for effective interventions.

Managing Atherosclerotic Cardiovascular Risk in Young Adults: JACC State-of-the-Art Review

There is a need to identify high-risk features that predict early-onset atherosclerotic cardiovascular disease (ASCVD). The authors provide insights to help clinicians identify and address high-risk conditions in the 20- to 39-year age range (young adults). These include tobacco use, elevated blood pressure/hypertension, family history of premature ASCVD, primary severe hypercholesterolemia such as familial hypercholesterolemia, diabetes with diabetes-specific risk-enhancing factors, or the presence of multiple other risk-enhancing factors, including in females, a history of pre-eclampsia or menopause under age 40. The authors update current thinking on lipid risk factors such as triglycerides, non-high-density lipoprotein cholesterol, apolipoprotein B, or lipoprotein (a) that are useful in understanding an individual's long-term ASCVD risk. The authors review emerging strategies, such as coronary artery calcium and polygenic risk scores in this age group, that have potential clinical utility, but whose best use remains uncertain. Finally, the authors discuss both the obstacles and opportunities for addressing prevention in early adulthood.

Neck Circumference Predicts Mortality in Hospitalized COVID-19 Patients

We aimed to determine whether neck circumference predicts mortality among hospitalized COVID-19 patients with respiratory failure. We performed a prospective multicenter (Italy and Brasil) study carried out from March to December 2020 on 440 hospitalized COVID-19 patients with respiratory failure. Baseline neck circumference was measured. The study outcome was 30- and 60-days mortality. Female and male participants were classified as “large neck” when exceeding fourth-quartile. Patients had a median age of 65 years (IQR 54–76), 68% were male. One-quarter of patients presented with grade-1 or higher obesity. The median neck circumference was 40 cm (IQR 38–43): 38 cm (IQR 36–40) for female and 41 cm (IQR 39–44) for male subjects. “Large neck” patients had a significantly higher prevalence of hypertension (63 vs. 48%), diabetes (33 vs. 19%), obesity (26 vs. 14%), and elevated C-reactive protein (CRP) (98 vs. 88%). The cumulative mortality rate was 13.1% (n = 52) and 15.9% (n = 63) at 30 and 60 days, respectively. After adjusting for age, BMI, relevant comorbidities, and high C-reactive protein to albumin ratio, “large neck” patients showed a significantly increased risk of death at 30- (adjusted HR 2.50; 95% CI 1.18–5.29; p = 0.017) and 60-days (adjusted HR 2.26; 95% CI 1.14–4.46; p = 0.019). Neck circumference is easy to collect and provides additional prognostic information to BMI. Among hospitalized COVID-19 patients with respiratory failure, those with large neck phenotype had a more than double risk of death at 30 and 60 days.

Prevalence and significance of risk enhancing biomarkers in the United States population at intermediate risk for atherosclerotic disease: Risk Enhancing Factors in Intermediate Risk for ASCVD

BACKGROUND

Pooled cohort equations (PCEs) estimate 10-year risk for atherosclerotic cardiovascular disease (ASCVD) in US adults. One use is to guide statin eligibility. However, PCEs risk estimate is inaccurate in some US subpopulations.

OBJECTIVE

Recent cholesterol guidelines proposed addition of risk enhancing factors to improve risk assessment for selection of statin therapy. This study examines frequencies of several risk enhancing biomarkers in NHANES subjects at intermediate risk (7.5 -<20% 10-year risk for ASCVD) and considers how they may be used to better assess risk for individuals.

METHODS

Prevalence of the following biomarkers were determined; elevations in apolipoprotein B-containing lipoproteins, i.e., LDL cholesterol (LDL-C) (160-189 mg/dL), non-HDL-cholesterol (non-HDL-C) (190-219 mg/dL), or total apolipoprotein B (apoB) (≥ 130 mg/dL), serum triglyceride (≥175 mg/dL), hemoglobin A1c (5.7-6.4%), high sensitivity C-reactive protein (2-10 mg/L), and waist circumference ≥ 102 cm, and abnormal estimated glomerular filtration rate (15 - ≤ 60 mg/min/1.73 m²).

RESULTS

25% of NHANES population had intermediate risk. In this subpopulation, 85% had ≥ 1 biomarkers-similarly in women and men-with a third having ≥3 abnormal markers. Frequencies were not age-related, except in those 40-49 years, in whom > 40% had ≥3 abnormal biomarkers. It made little difference whether LDL-C, non-HDL-C or apoB was used as the atherogenic lipoprotein.

CONCLUSION

Three or more enhancing risk factors in intermediate risk subjects can complement PCE-estimated 10-year risk and guide the patient-provider discussion toward use of lipid-lowering medication. Future research is needed to integrate risk estimates by PCE and multiple risk enhancers.

The Impact of Obesity on SARS-CoV-2 Pandemic Mortality Risk

The COVID-19 pandemic has uncovered the increased susceptibility of individuals with obesity to infection and severe disease leading to hospitalization and death. Studies in New York City demonstrated that after advanced age, obesity was the most common risk factor leading to severe disease and death from COVID-19. While the connection has been recognized, there has not been a general recognition of the potential mechanisms for this link between excess body fat and mortality from this viral pandemic including respiratory complications and sequelae of increased activation of the immune system. Despite plans for vaccination of the global population, the risk community spread of COVID-19 and future pandemics will be linked in part to obesity and immunity. This review will detail a number of potential mechanisms through which obesity may contribute to the lethality of this viral infection. These insights will hopefully lead to a greater emphasis on obesity prevention and treatment as part of the global response to this and future pandemic threats.

Metabolic flexibility during late pregnancy is associated with neonatal adiposity

The aim of this study was to determine the relationships between maternal metabolic flexibility during pregnancy and neonatal health outcomes. Percent change in lipid oxidation (before and after a high-fat meal) was calculated as the measure of "metabolic flexibility". Neonatal adiposity was assessed within 48 h of delivery by skinfold anthropometry. Metabolic flexibility (r = -0.271, p = 0.034), maternal HOMA-IR (r = 0.280, p = 0.030), and maternal body mass index (r = 0.299, p = 0.018) were correlated with neonatal subscapular skinfold (i.e., measure of neonatal adiposity). Clinical Trail Registration Number: NCT03504319. Novelty: This is the first study to link maternal metabolic flexibility, body mass index, and insulin resistance during pregnancy to neonatal adiposity at parturition.

Utility of metabolic syndrome as a risk enhancing factor in decision of statin use

BACKGROUND

Statins effectively reduce risk for atherosclerotic cardiovascular disease (ASCVD) when 10-year risk is ≥ 7.5%. In many patients at intermediate risk (7.5-<20% risk), there is uncertainty about reliability of risk assessment by current pooled cohort equations (PCE). A decision to initiate statin therapy is favored by several risk enhancing factors not employed in PCEs.

OBJECTIVE

This study examines the scope of the metabolic syndrome, a risk enhancing factor, and its principal sequala, diabetes, in 26,796 US adults age 40-75 years from the NHANES survey data, 1999-2016.

METHODS

The prevalence of metabolic syndrome without diabetes (MetS+) and of diabetes (DM+) were determined for 10-year risk categories estimated to be low (<7.5%), intermediate (7.5% -< 20%) and high (≥20%). Data were weighted to account for complex study design.

RESULTS

90.4% of the population was free of ASCVD. In subjects projected to be at low risk by PCEs, MetS+ was present in 15.0% and 17.6% of women and men, respectively. MetS + increased to 30.6% of women and 29.6% of men at intermediate risk, and to 21.5% of women and 32.2% of men at high risk. In addition, DM+ was present in 6.1%/5.3% (F/M) of low risk individuals, 20.1%/14.8% (F/M) of intermediate risk subjects, and 44.3%/39.4% (F/M) of high-risk persons. Prevalence of both MetS+ and DM + rose progressively with age in women and men.

CONCLUSIONS

MetS+ and DM + are common multiplex risk factors that predispose to higher lifetime risk and support statin therapy in patients at intermediate and high risk.

Correlation Between the Distribution of Abdominal, Pericardial and Subcutaneous Fat and Muscle and Age and Gender in a Middle-Aged and Elderly Population

OBJECTIVE

The present study aimed to explore the relationships between the distribution of abdominal fat and muscle and age and gender in a middle-aged and elderly population.

METHODS

The levels of abdominal (visceral and subcutaneous) fat, pericardial fat, and psoas major muscle were measured in subjects who had physical examinations at the Health and Medical Department of Peking Union Medical College Hospital from July 2019 to June 2020. The relationship between fat in different areas (ie, different types of fat) and the relationship between different types of fat and the psoas major muscle were investigated in the context of different genders and ages.

RESULTS

The distribution of fat and muscle differed between males and females of the middle-aged and elderly study sample. Volumes of pericardial fat, total abdominal fat, and visceral fat were significantly lower in females than in males, and the area of the psoas major muscle was also significantly lower in females than in males. Levels of subcutaneous fat and total abdominal fat showed no significant correlation with age. The level of muscle showed a significant negative correlation with age.

CONCLUSION

1) Within the middle-aged and elderly sample, male subjects had higher levels than females of all types of fat except for abdominal subcutaneous fat, and had higher levels of psoas muscle than females. 2) Pericardial fat increased with age, whereas levels of abdominal fat did not change significantly with age. 3) The area of psoas major muscle appears to be positively correlated with volumes of all types of fat: subjects with more fat tended to have higher levels of psoas major muscle.

Comparisons of conventional and novel anthropometric obesity indices to predict metabolic syndrome among vegetarians in Malaysia

Our study aimed to compare the ability of anthropometric obesity indices to predict MetS and to determine the sex-specific optimal cut-off values for MetS among Malaysian vegetarians. Body weight, height, waist circumference (WC), blood pressure (BP), fasting venous blood sample were collected from 273 vegetarians in Selangor and Kuala Lumpur, Malaysia. The abilities of body mass index (BMI), body fat percentage (BF%), waist to height ratio (WHtR), lipid accumulation product (LAP), visceral adiposity index (VAI), a body shape index (ABSI), and body roundness index (BRI) to identify MetS were tested using receiver operating characteristic (ROC) curve analyses. MetS was defined according to the Joint Interim Statement 2009. The ROC curve analyses show that BMI, BF%, WHtR, LAP and VAI were able to discriminate MetS in both sexes. LAP was a better predictor to predict MetS, followed by WHtR for male and female vegetarians. The suggested WHtR’s optimal cut-offs and LAP’s optimal cut-offs for MetS for male and female vegetarians were 0.541, 0.532, 41.435 and 21.743, respectively. In conclusion, LAP was a better predictor to predict MetS than other anthropometric obesity indices. However, WHtR could be an alternative obesity index in large epidemiology survey due to its convenient and cost-effective characteristics.

High body fat percentage is associated with primary aldosteronism: a cross-sectional study

BACKGROUND

Excess aldosterone has been shown to be associated with obesity; however, there is currently a lack of data regarding the relationship between percentage of body fat and primary aldosteronism (PA), particularly pertaining to Asian populations. Furthermore, essential hypertension may mimic the condition of PA and there needs to be differentiation between the two. This study aimed to assess the association between percentage of body fat and PA.

METHODS

A cross-sectional study was conducted in the outpatient department of the Endocrine and Metabolism Unit of the tertiary care medical center in Thailand. Data was obtained from 79 patients who had been screened for PA due to hypertension in young-onset, hypokalemia, adrenal incidentaloma or resistance hypertension. Essential hypertension was defined as patients who had high blood pressure and were negative for PA screening. Body fat percentage was assessed by bioelectrical impedance analysis. The relationship between percentage of body fat and a diagnosis of PA was assessed using logistic regression analysis, including adjustment for confounding factors.

RESULTS

The participants were divided into a PA group (n = 41) and an essential hypertension group (n = 38). After controlling for confounding variables (age, sex, body mass index, cholesterol and insulin resistance status), the odds ratio of having PA in males with a percentage of body fat > 25% and females with percentage > 30% was 1.82 (95%CI = 1.79-1.86, p < 0.001).

CONCLUSION

A higher percentage of body fat is associated with an increased risk of PA. Further studies need to be conducted to confirm the relationship between body fat percentage and PA.

Choline Intake as Supplement or as a Component of Eggs Increases Plasma Choline and Reduces Interleukin-6 without Modifying Plasma Cholesterol in Participants with Metabolic Syndrome

Metabolic syndrome (MetS) is characterized by low-grade inflammation and insulin resistance, which increase the risk of heart disease. Eggs have numerous nutrients including choline, carotenoids, and fat-soluble vitamins that may protect against these conditions. Egg phosphatidylcholine (PC) is a major contributor of dietary choline in the American diet. However, uncertainty remains regarding eggs due to their high concentration of cholesterol. In this study, we evaluated the effect of two sources of choline, whole eggs (a source of PC) and a choline supplement (choline bitartrate, CB), on plasma lipids, glucose, insulin resistance, and inflammatory biomarkers. We recruited 23 subjects with MetS to participate in this randomized cross-over intervention. After a 2-week washout, with no choline intake, participants were randomly allocated to consume three eggs/day or CB (~400 mg choline/d for both) for 4 weeks. After a 3-week washout period, they were allocated to the alternate treatment. Dietary records indicated higher concentrations of vitamin E and selenium during the egg period (p < 0.01). Interestingly, there were no changes in plasma total, low density lipoprotein (LDL)- or high density lipoprotein (HDL)-cholesterol, triglycerides, or glucose, compared either to baseline or between treatments. In contrast, interleukin-6 was reduced, with both sources of choline compared to baseline, while eggs also had an effect on lowering C-reactive protein, insulin, and insulin resistance compared to baseline. This study demonstrates that in a MetS population, intake of three eggs per day does not increase plasma LDL cholesterol, and has additional benefits on biomarkers of disease compared to a choline supplement, possibly due to the presence of other antioxidants in eggs.

Cold-Activated Brown Adipose Tissue is Associated with Less Cardiometabolic Dysfunction in Young Adults with Obesity

OBJECTIVE

This study aimed to test the hypothesis that young adults with obesity and cold-activated brown adipose tissue (BAT) are less likely to have metabolic dysfunction (dyslipidemia, insulin resistance, and hypertension) than those without cold-activated BAT. Previous studies have noted a potentially protective effect of BAT and higher adiponectin/leptin ratios, but they have acknowledged that the clinical implications of these findings remain uncertain.

METHODS

Twenty-one females and twenty-three males with obesity (BMI ≥ 30 kg/m² ) underwent a 2-hour cooling protocol before ¹⁸ F-fluorodeoxyglucose (¹⁸ F-FDG)-positron emission tomography/x-ray computed tomography scan to determine the prevalence, volume, and ¹⁸ F-FDG uptake of cold-activated BAT.

RESULTS

Cold-activated BAT was identified in 43% of participants (11 female, 8 male); females had greater ¹⁸ F-FDG uptake. Those with cold-activated BAT had a lesser degree of metabolic dysfunction. Cold-activated BAT volume correlated with triglycerides (inversely) and adiponectin (concordantly). Body-mass-adjusted cold-activated BAT activity correlated with high-density lipoprotein cholesterol (concordantly). Males with cold-activated BAT had lower leptin and higher adiponectin/leptin ratio.

CONCLUSIONS

A high prevalence of cold-activated BAT was found in the study participants. BAT could be important in decreasing metabolic dysfunction among young adults with obesity, making it a potential target for treating metabolically unhealthy obesity.

Body mass index is associated with epigenetic age acceleration in the visceral adipose tissue of subjects with severe obesity

Background

There is solid evidence that obesity induces the acceleration of liver epigenetic aging. However, unlike easily accessible blood or subcutaneous adipose tissue, little is known about the impact of obesity on epigenetic aging of metabolically active visceral adipose tissue (VAT). Herein, we aimed to test whether obesity accelerates VAT epigenetic aging in subjects with severe obesity.

Results

A significant and positive correlation between chronological age and epigenetic age, estimated with a reduced version of the Horvath’s epigenetic clock, was found in both blood (r = 0.78, p = 9.4 × 10⁻¹²) and VAT (r = 0.80, p = 1.1 × 10⁻¹²). Epigenetic age acceleration, defined as the residual resulting from regressing epigenetic age on chronological age, was significantly correlated with body mass index (BMI) in VAT (r = 0.29, p = 0.037). Multivariate linear regression analysis showed that, after adjusting for chronological age, sex and metabolic syndrome status, BMI remained significantly associated with epigenetic age acceleration in VAT (beta = 0.15, p = 0.035), equivalent to 2.3 years for each 10 BMI units. Binomial logistic regression showed that BMI-adjusted epigenetic age acceleration in VAT was significantly associated with a higher loss of excess body weight following biliopancreatic diversion with duodenal switch surgery (odds ratio = 1.21; 95% CI = 1.04–1.48; p = 0.03).

Conclusions

Epigenetic age acceleration increases with BMI in VAT, but not in blood, as previously reported in liver. These results suggest that obesity is associated with epigenetic age acceleration of metabolically active tissues. Further studies that deepen the physiological relevance of VAT epigenetic aging will help to better understand the onset of metabolic syndrome and weight loss dynamics following bariatric surgery.

Cognitive flexibility and the health of Black college-attending young adults experiencing interpersonal racial discrimination

This study examined the utility of cognitive flexibility for the health of college-attending Black young adults facing chronic interpersonal racial discrimination in a sample of 218 healthy students attending a predominantly White university in the southeastern United States. Path and simple slope analysis indicated that cognitive flexibility moderated the association between racial discrimination and waist circumference but not depressive symptoms. At high cognitive flexibility, more experiences of discrimination were significantly associated with larger waist circumference. Findings suggest that cognitive flexibility may be detrimental for physical health and not of paramount importance for mental health of college-attending Black young adults.

Differential open chromatin profile and transcriptomic signature define depot-specific human subcutaneous preadipocytes: primary outcomes

Background

Increased lower body fat is associated with reduced cardiometabolic risk. The molecular basis for depot-specific differences in gluteofemoral (GF) compared with abdominal (A) subcutaneous adipocyte function is poorly understood. In the current report, we used a combination of Assay for Transposase-Accessible Chromatin followed by sequencing (ATAC-seq), RNA-seq, and chromatin immunoprecipitation (ChIP)-qPCR analyses that provide evidence that depot-specific gene expression patterns are associated with differential epigenetic chromatin signatures.

Methods

Preadipocytes cultured from A and GF adipose tissue obtained from premenopausal apple-shaped women were used to perform transcriptome analysis by RNA-seq and assess accessible chromatin regions by ATAC-seq. We measured mRNA expression and performed ChIP-qPCR experiments for histone modifications of active (H3K4me3) and repressed chromatin (H3K27me3) regions respectively on the promoter regions of differentially expressed genes.

Results

RNA-seq experiments revealed an A-fat and GF-fat selective gene expression signature, with 126 genes upregulated in abdominal preadipocytes and 90 genes upregulated in GF cells. ATAC-seq identified almost 10-times more A-specific chromatin-accessible regions. Using a combined analysis of ATAC-seq and global gene expression data, we identified 74 of the 126 abdominal-specific genes (59%) with A-specific accessible chromatin sites within 200 kb of the transcription start site (TSS), including HOXA3, HOXA5, IL8, IL1b, and IL6. Interestingly, only 14 of the 90 GF-specific genes (15%) had GF-specific accessible chromatin sites within 200 kb of the corresponding TSS, including HOXC13 and HOTAIR, whereas 25 of them (28%) had abdominal-specific accessible chromatin sites. ChIP-qPCR experiments confirmed that the active H3K4me3 chromatin mark was significantly enriched at the promoter regions of HOXA5 and HOXA3 genes in abdominal preadipocytes, while H3K27me3 was less abundant relative to chromatin from GF. This is consistent with their A-fat specific gene expression pattern. Conversely, analysis of the promoter regions of the GF specific HOTAIR and HOXC13 genes exhibited high H3K4me3 and low H3K27me3 levels in GF chromatin compared to A chromatin.

Conclusions

Global transcriptome and open chromatin analyses of depot-specific preadipocytes identified their gene expression signature and differential open chromatin profile. Interestingly, A-fat-specific open chromatin regions can be observed in the proximity of GF-fat genes, but not vice versa.

Trial registration

Clinicaltrials.gov, NCT01745471. Registered 5 December 2012.

Electronic supplementary material

The online version of this article (10.1186/s13148-018-0582-0) contains supplementary material, which is available to authorized users.

Upper body fat predicts metabolic syndrome similarly in men and women

BACKGROUND

The metabolic syndrome is a constellation of risk factors including dyslipidemia, dysglycemia, hypertension, a pro-inflammatory state, and a prothrombotic state. All of these factors are accentuated by obesity. However, obesity can be defined by body mass index (BMI), percent body fat, or by body fat distribution. The latter consists of upper body fat (subcutaneous and visceral fat) and lower body fat (gluteofemoral fat). Waist circumference is a common surrogate marker for upper body fat.

METHODS

Data from the National Health and Nutrition Examination Survey (NHANES) for the years 1999-2006 was examined for associations of metabolic risk factors with percent body fat, waist circumference, and BMI.

RESULTS

Associations between absolute measures of waist circumference and risk factors were similiar for men and women. The similarities of associations between waist circumference and risk factors suggests that greater visceral fat in men does not accentuate the influence of upper body fat on risk factors.

CONCLUSIONS

Different waist concumference values should not be used to define abdominal obesity in men and women.