Relation of Changes in Body Fat Distribution to Oxidative Stress.
ABSTRACT: Android fat is a surrogate measure of visceral obesity in the truncal region. Both visceral adiposity and oxidative stress (OS) are linked to cardiometabolic risk factors and clinical cardiovascular disease. However, whether body fat distribution (android vs gynoid) is associated with OS remains unknown. We hypothesized that increased android fat will be associated with greater OS. Body fat distribution and markers of OS, including plasma levels of reduced (cysteine and glutathione) and oxidized (cystine and glutathione disulfide) aminothiols, were estimated in 711 volunteers (67% female, 23% black, mean age 48?±?11) enrolled in the Emory Georgia Tech Predictive Health study. At 1 year, 498 subjects had repeat testing. At baseline, anthropometric and fat distribution indexes, including body mass index, waist circumference, weight/hip ratio, and android and gynoid fat mass correlated with lower plasma concentrations of glutathione and higher cystine levels indicative of higher OS. At 1 year, the change in android but not gynoid fat mass or body mass index negatively correlated with the change in the plasma glutathione level after adjustment for cardiovascular risk factors. Increased body fat, specifically android fat mass, is an independent determinant of systemic OS, and its change is associated with a simultaneous change in OS, measured as plasma glutathione. In conclusion, our findings suggest that excess android or visceral fat contributes to the development of cardiovascular disease through modulating OS.
Project description:OBJECTIVE:This study aimed to quantify the associations of regional fat mass and fat-free mass with systolic blood pressure. METHODS:This analysis combined individual participant data from two large-scale imaging studies: UK Biobank and Oxford BioBank. In both studies, participants were interviewed and measured, and they underwent dual-energy x-ray absorptiometry imaging. Linear regression was used to relate systolic blood pressure to anthropometric measures of adiposity (BMI, waist circumference, and waist to hip ratio) and dual-energy x-ray absorptiometry-derived measures of body composition (visceral android fat, subcutaneous android fat, subcutaneous gynoid fat, and fat-free mass). RESULTS:Among 10,260 participants (mean age 49; 96% white), systolic blood pressure was positively associated with visceral android fat (3.2 mmHg/SD in men; 2.8 mmHg/SD in women) and fat-free mass (1.92 mmHg/SD in men; 1.64 mmHg/SD in women), but there was no evidence of an association with subcutaneous android or gynoid fat. Associations of systolic blood pressure with BMI were slightly steeper than those with waist circumference or waist to hip ratio; these associations remained unchanged following adjustment for fat-free mass, but adjustment for visceral android fat eliminated associations with waist circumference and waist to hip ratio and more than halved associations with BMI. CONCLUSIONS:This analysis indicates that visceral fat is the primary etiological component of excess adiposity underlying the development of adiposity-related hypertension.
Project description:Whether fat is beneficial or detrimental to bones is still controversial, which may be due to inequivalence of the fat mass. Our objective is to define the effect of body fat and its distribution on bone quality in healthy Chinese men. A total of 228 men, aged from 38 to 89 years, were recruited. BMD, trabecular bone score (TBS), and body fat distribution were measured by dual-energy X-ray absorptiometry. Subcutaneous and visceral fat were assessed by MRI. In the Pearson correlation analysis, lumbar spine BMD exhibited positive associations with total and all regional fat depots, regardless of the fat distribution. However, the correlation disappeared with adjusted covariables of age, BMI, HDL-C, and HbA1c%. TBS was negatively correlated with fat mass. In multiple linear regression models, android fat (and not gynoid, trunk, or limbs fat) showed significant inverse association with TBS (β = -0.611, P < 0.001). Furthermore, visceral fat was described as a pathogenic fat harmful to TBS, even after adjusting for age and BMI (β = -0.280, P = 0.017). Our findings suggested that body fat mass, especially android fat and visceral fat, may have negative effects on bone microstructure; whereas body fat mass contributes to BMD through mechanical loading.
Project description:BACKGROUND: Fat accumulation in android compartments may confer increased metabolic risk. The incremental utility of measuring regional fat deposition in association with metabolic syndrome (MS) has not been well described particularly in an elderly population. METHODS AND FINDINGS: As part of the Korean Longitudinal Study on Health and Aging, which is a community-based cohort study of people aged more than 65 years, subjects (287 male, 75.9±8.6 years and 278 female, 76.0±8.8 years) with regional body composition data using Dual energy X-ray absorptiometry for android/gynoid area, computed tomography for visceral/subcutaneous adipose tissue (VAT/SAT), and cardiometabolic markers including adiponectin and high-sensitivity CRP were enrolled. We investigated the relationship between regional body composition and MS in multivariate regression models. Mean VAT and SAT area was 131.4±65.5 cm(2) and 126.9±55.2 cm(2) in men (P?=?0.045) and 120.0±46.7 cm(2) and 211.8±65.9 cm(2) in women (P<0.01). Mean android and gynoid fat amount was 1.8±0.8 kg and 2.5±0.8 kg in men and 2.0±0.6 kg and 3.3±0.8 kg in women, respectively (both P<0.01). VAT area and android fat amount was strongly correlated with most metabolic risk factors compared to SAT or gynoid fat. Furthermore, android fat amount was significantly associated with clustering of MS components after adjustment for multiple parameters including age, gender, adiponectin, hsCRP, a surrogate marker of insulin resistance, whole body fat mass and VAT area. CONCLUSIONS: Our findings are consistent with the hypothesized role of android fat as a pathogenic fat depot in the MS. Measurement of android fat may provide a more complete understanding of metabolic risk associated with variations in fat distribution.
Project description:AIM: To determine the independent and commingling effect of android and gynoid percent fat (measured using Dual Energy X-Ray Absorptiometry) on cardiometabolic dysregulation in normal weight American adults. METHODS: The 2005-2006 data (n=1802) from the United States National Health and Nutritional Examination Surveys (NHANES) were used in this study. Associations of android percent fat, gynoid percent fat and their joint occurrence with risks of cardiometabolic risk factors were estimated using prevalence odds ratios from logistic regression analyses. RESULTS: Android-gynoid percent fat ratio was more highly correlated with cardiometabolic dysregulation than android percent fat, gynoid percent fat or body mass index. Commingling of android and gynoid adiposities was associated with much greater odds of cardiometabolic risk factors than either android or gynoid adiposities. Commingling of android and gynoid adiposities was associated with 1.75 (95% confidence interval (CI)=1.42-2.93), 1.48 (95% CI=1.32-1.91), 1.61 (95% CI=1.50-1.89), 3.56 (95% CI=2.91-4.11) and 1.86 (95% CI=1.49-1.96) increased odds of elevated glucose, elevated blood pressure, elevated low-density lipoprotein-cholesterol, elevated triglyceride and low high-density lipoprotein-cholesterol, respectively. CONCLUSIONS: Normal weight subjects who present with both android and gynoid adiposities should be advised of the associated health risks. Both android and gynoid fat accumulations should be considered in developing public health strategies for reducing cardiometabolic disease risk in normal weight subjects.
Project description:Maternal polyunsaturated fatty acid (PUFA) concentrations during pregnancy may have persistent effects on growth and adiposity in the offspring. A suboptimal maternal diet during pregnancy might lead to fetal cardiometabolic adaptations with persistent consequences in the offspring.We examined the associations of maternal PUFA concentrations during pregnancy with childhood general and abdominal fat-distribution measures.In a population-based, prospective cohort study of 4830 mothers and their children, we measured maternal second-trimester plasma n-3 (?-3) and n-6 (?-6) PUFA concentrations. At the median age of 6.0 y (95% range: 5.6, 7.9 y), we measured childhood body mass index (BMI), the fat mass percentage, and the android:gynoid fat ratio with the use of dual-energy X-ray absorptiometry and measured the preperitoneal abdominal fat area with the use of ultrasound. Analyses were adjusted for maternal and childhood sociodemographic- and lifestyle-related characteristics.We observed that higher maternal total n-3 PUFA concentrations, and specifically those of eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid, were associated with a lower childhood total-body fat percentage and a lower android:gynoid fat mass ratio (P< 0.05) but not with childhood BMI and the abdominal preperitoneal fat mass area. Higher maternal total n-6 PUFA concentrations, and specifically those of dihomo-?-linolenic acid, were associated with a higher childhood total-body fat percentage, android:gynoid fat mass ratio, and abdominal preperitoneal fat mass area (P< 0.05) but not with childhood BMI. In line with these findings, a higher maternal n-6:n-3 PUFA ratio was associated with higher childhood total-body and abdominal fat mass.Lower maternal n-3 PUFA concentrations and higher n-6 PUFA concentrations during pregnancy are associated with higher body fat and abdominal fat in childhood. Additional studies are needed to replicate these observations and to explore the causality, the underlying pathways, and the long-term cardiometabolic consequences.
Project description:BACKGROUND:Maternal caffeine intake during pregnancy is associated with an increased risk of childhood obesity. Studies in adults suggest that caffeine intake might also directly affect visceral and liver fat deposition, which are strong risk factors for cardio-metabolic disease. OBJECTIVE:To assess the associations of maternal caffeine intake during pregnancy with childhood general, abdominal, and liver fat mass at 10?years of age. METHODS:In a population-based cohort from early pregnancy onwards among 4770 mothers and children, we assessed maternal caffeine intake during pregnancy and childhood fat mass at age 10?years. RESULTS:Compared with children whose mothers consumed <2 units of caffeine per day during pregnancy, those whose mothers consumed 4-5.9 and ?6 units of caffeine per day had a higher body mass index, total body fat mass index, android/gynoid fat mass ratio, and abdominal subcutaneous and visceral fat mass indices. Children whose mothers consumed 4-5.9 units of caffeine per day had a higher liver fat fraction. The associations with abdominal visceral fat and liver fat persisted after taking childhood total body fat mass into account. CONCLUSIONS:High maternal caffeine intake during pregnancy was associated with higher childhood body mass index, total body fat, abdominal visceral fat, and liver fat. The associations with childhood abdominal visceral fat and liver fat fraction were independent of childhood total body fat. This suggests differential fat accumulation in these depots, which may increase susceptibility to cardio-metabolic disease in later life.
Project description:Background Visceral adipose tissue ( VAT ) and other measures of central obesity predict incident atherosclerotic cardiovascular disease ( ASCVD ) events in middle-aged individuals, but these associations are less certain in older individuals age 70 years and older. Our objective was to estimate the associations of VAT and the android-gynoid fat mass ratio, another measure of central obesity, with incident ASCVD events among a large cohort of older men. Methods and Results Two thousand eight hundred ninety-nine men (mean [ SD ] age 76.3 [5.5] years) enrolled in the Outcomes of Sleep Disorders in Older Men study had rigorous adjudication of incident ASCVD events (myocardial infarction, coronary heart disease death, or fatal or nonfatal stroke). We used proportional hazards models to estimate the hazard ratios for incident ASCVD per SD increase of VAT or android-gynoid fat mass ratio (measured at baseline with dual-energy absorptiometry), adjusted for age, race, education, systolic blood pressure, smoking status, oxidized low-density lipoprotein level, treatment for hypertension, statin use, aspirin use, presence of diabetes mellitus, and study enrollment site. Over a mean ( SD ) follow-up period of 7.9 (3.4) years, 424 men (14.6%) had an incident ASCVD event. Neither VAT nor android-gynoid fat mass ratio were associated with incident ASCVD events, either unadjusted or after multivariable-adjustment (hazard ratios [95% confidence interval ] per SD increase 1.02 [0.92-1.13] and 1.05 [0.95-1.17], respectively). Conclusions Central adipose tissue, as measured by VAT or android-gynoid fat mass ratio, was not associated with incident ASCVD events in this study of older men.
Project description:AIM:Based on its regulatory action on glucagon-like peptide 1, dipeptidyl peptidase IV (DPP-IV) has increasingly been linked to Type 2 diabetes. However, there is no evidence as to how this normal modulatory enzyme leads to pathology. It is thought that DPP-IV is affected by the development of obesity, which is a common precursor to Type 2 diabetes. Little is known about the relationship between DPP-IV activity in plasma and specific body composition measures. MAIN METHODS:In the current study, plasma DPP-IV activity and body composition measures were collected from 111 healthy subjects between the ages of 19 and 70 years old for analysis. KEY FINDINGS:The mean plasma DPP-IV activity was 35.9U/L ± 12.3, falling within normal reference value range presented by Durinx et al. DPP-IV activity was negatively correlated with absolute body fat mass, but absolute lean mass was positively correlated. Consistent with the findings, DPP-IV activity was also negatively correlated with absolute gynoid fat (p = 0.0047). DPP-IV activity did not have a significant correlation with absolute android fat mass, visceral adipose tissue, BMI, and age. SIGNIFICANCE:From these results, it can be concluded that high activity of DPP-IV is not indicative of pathology, and specific body composition components may influence soluble DPP-IV activity in the blood.
Project description:High birth weight and greater weight gain in infancy have been associated with increased risk of obesity as assessed using body mass index, but few studies have examined associations with direct measures of fat and lean mass. This study examined associations of birth weight and weight and height gain in infancy, childhood and adolescence with fat and lean mass in early old age.A total of 746 men and 812 women in England, Scotland and Wales from the MRC National Survey of Health and Development whose heights and weights had been prospectively ascertained across childhood and adolescence and who had dual energy X-ray absorptiometry measures at age 60-64 years.Associations of birth weight and standardised weight and height (0-2 (weight only), 2-4, 4-7, 7-11, 11-15, 15-20 years) gain velocities with outcome measures were examined.Higher birth weight was associated with higher lean mass and lower android/gynoid ratio at age 60-64 years. For example, the mean difference in lean mass per 1 standard deviation increase in birth weight was 1.54 kg in males (95% confidence interval=1.04, 2.03) and 0.78 kg in females (0.41, 1.14). Greater weight gain in infancy was associated with higher lean mass, whereas greater gains in weight in later childhood and adolescence were associated with higher fat and lean mass, and fat/lean and android/gynoid ratios. Across growth intervals greater height gain was associated with higher lean but not fat mass, and with lower fat/lean and android/gynoid ratios.Findings suggest that growth in early life may have lasting effects on fat and lean mass. Greater weight gain before birth and in infancy may be beneficial by leading to higher lean mass, whereas greater weight gain in later childhood and adolescence may be detrimental by leading to higher fat/lean and android/gynoid ratios.
Project description:The adenylate cyclase 3 (ADCY3) gene is involved in the regulation of several metabolic processes including the development and function of adipose tissue. The effects of the ADCY3 rs10182181 genetic variant on changes in body composition depending on the macronutrient distribution intake after 16 weeks of the dietary intervention were tested. The ADCY3 genetic variant was genotyped in 147 overweight or obese subjects, who were randomly assigned to one of the two diets varying in macronutrient content: a moderately-high-protein diet and a low-fat diet. Anthropometric and body composition measurements (DEXA scan) were recorded. Significant interactions between the ADCY3 genotype and dietary intervention on changes in weight, waist circumference, and body composition were found after adjustment for covariates. Thus, in the moderately-high-protein diet group, the G allele was associated with a lower decrease of fat mass, trunk and android fat, and a greater decrease in lean mass. Conversely, in the low-fat diet group carrying the G allele was associated with a greater decrease in trunk, android, gynoid, and visceral fat. Subjects carrying the G allele of the rs10182181 polymorphism may benefit more in terms of weight loss and improvement of body composition measurements when undertaking a hypocaloric low-fat diet as compared to a moderately-high-protein diet.