Yunfeng Xiao

Associations of serum 25-hydroxyvitamin D3 levels with visceral adipose tissue in Chinese men with normal glucose tolerance.

Objective Decreased serum vitamin D level is a common observation in obese adults. Since no Chinese population-based study has yet evaluated the relationship between serum vitamin D levels and the accurate adiposity variables, this study investigated the association of serum vitamin D (assessed by 25-hydroxyvitamin D3 [25(OH)D3]) levels with precise body fat content and distribution in a cohort of Chinese men. Methods Serum samples were collected from a total of 567 men with normal glucose tolerance (NGT) for assessment by electrochemiluminescence immunoassay to measure 25(OH)D3 levels. In addition, each participant underwent bioelectrical impedance analysis to quantify total body fat and magnetic resonance imaging to measure visceral fat area (VFA) and subcutaneous fat area (SFA). Results Overweight/obese (BMI ≥25 kg/m2) subjects had significantly lower serum 25(OH)D3 levels than non-overweight/non-obese (BMI <25 kg/m2) subjects (P  = 0.029). Greater fat mass and VFA were accompanied by a downward trend in serum 25(OH)D3 levels (P for trend <0.01). Among overweight/obese subjects, those with body fat percent ≥25% also had significantly lower serum 25(OH)D3 levels (P <0.05). Moreover, participants with VFA ≥80 cm2 had significantly lower serum 25(OH)D3 (P <0.05), regardless of BMI value. VFA was independently correlated with serum 25(OH)D3 levels (β  =  −0.023, P <0.001), even after adjustments for confounding factors. In addition, serum 25(OH)D3 levels were found to decrease by 0.26 ng/mL per 10 cm2 increment of VFA. Conclusions Serum 25(OH)D3 levels were inversely associated with VFA in Chinese men with NGT.

Serum glycated albumin is inversely influenced by fat mass and visceral adipose tissue in Chinese with normal glucose tolerance.

Background Recent studies have revealed that body mass index (BMI) inversely influenced serum glycated albumin (GA), which may cause an underestimation of GA-monitored short-term hyperglycemic control. Objective This study was to investigate the association between anthropometric variables (BMI and waist circumference (W)) and accurate adiposity variables (percentage of body fat (%fat), fat mass, free fat mass (FFM), subcutaneous fat area (SFA), and visceral fat area (VFA)) with serum GA. Design A total of 2563 subjects (1037 men, 593 premenopausal women, and 933 postmenopausal women) with normal glucose tolerance underwent bioelectrical impedance body fat content measurement and magnetic resonance imaging. Serum GA and absolute value of GA (aGA) were measured by enzymatic assay. Results Compared to the BMI <25.0 kg/m2 group, the BMI ≥25.0 kg/m2 group had significantly higher fasting plasma glucose, glycated hemoglobin A1c, and body fat parameters including W, %fat, fat mass, FFM, SFA, and VFA, but significantly lower aGA, and GA in all the three sex- and menopause-stratified groups (all P<0.05). GA decreased with the increment of fat mass for all three groups (all P for trend <0.001). In the same BMI category, men and postmenopausal women with elevated %fat (men, ≥25%; women, ≥35%) still had significantly lower GA than those with normal %fat (men, <25%; women, <35%) (all P<0.05). Multiple stepwise regression showed that %fat, fat mass, and VFA were independently associated with GA. Conclusions Serum GA was inversely influenced by fat mass and visceral adipose tissue in Chinese with normal glucose tolerance.

Beneficial Effects of an 8-Week, Very Low Carbohydrate Diet Intervention on Obese Subjects

Aim. To investigate the effects of weight loss during an 8-week very low carbohydrate diet (VLCD) on improvement of metabolic parameters, adipose distribution and body composition, and insulin resistance and sensitivity in Chinese obese subjects. Methods. Fifty-three healthy obese volunteers were given an 8-week VLCD. The outcomes were changes in anthropometry, body composition, metabolic profile, abdominal fat distribution, liver fat percent (LFP), and insulin resistance and sensitivity. Results. A total of 46 (86.8%) obese subjects completed the study. The VLCD caused a weight loss of -8.7 ± 0.6 kg (mean ± standard error (SE), P < 0.0001) combined with a significant improvement of metabolic profile. In both male and female, nonesterified fatty acid (NEFA) significantly decreased (-166.2 ± 47.6  μ mol/L, P = 0.001) and β -hydroxybutyric acid (BHA) increased (0.15 ± 0.06 mmol/L, P = 0.004) after eight weeks of VLCD intervention. The significant reductions in subcutaneous fat area (SFA), visceral fat area (VFA), and LFP were -66.5 ± 7.9 cm(2), -35.3 ± 3.9 cm(2), and -16.4 ± 2.4%, respectively (all P values P < 0.0001). HOMA IR and HOMA β significantly decreased while whole body insulin sensitivity index (WBISI) increased (all P values P < 0.001). Conclusion. Eight weeks of VLCD was an effective intervention in obese subjects. These beneficial effects may be associated with enhanced hepatic and whole-body lipolysis and oxidation.

Neck circumference as an effective measure for identifying cardio-metabolic syndrome: a comparison with waist circumference

Neck circumference is a new anthropometric index for estimating obesity. We aimed to determine the relationship between neck circumference and body fat content and distribution as well as the efficacy of neck circumference for identifying visceral adiposity and metabolic disorders. A total of 1943 subjects (783 men, 1160 women) with a mean age of 58 ± 7 years were enrolled in this cross-sectional study. Metabolic syndrome was defined according to the standard in the 2013 China Guideline. Analyses were conducted to determine optimal neck circumference cutoff points for visceral adiposity quantified by magnetic resonance imaging, and to compare the performance of neck circumference with that of waist circumference in identifying abdominal obesity and metabolic disorders. Visceral fat content was independently correlated with neck circumference. Receiver operating characteristic curves showed that the area under the curve for the ability of neck circumference to determine visceral adiposity was 0.781 for men and 0.777 for women. Moreover, in men a neck circumference value of 38.5 cm had a sensitivity of 56.1 % and specificity of 83.5 %, and in women, a neck circumference value of 34.5 cm had a sensitivity of 58.1 % and specificity of 82.5 %. These values were the optimal cutoffs for identifying visceral obesity. There were no statistically significant differences between the proportions of metabolic syndrome and its components identified by an increased neck circumference and waist circumference. Neck circumference has the same power as waist circumference for identifying metabolic disorders in a Chinese population.

Positive relationship between serum low-density lipoprotein cholesterol levels and visceral fat in a Chinese nondiabetic population.

Background It has been reported that obesity and serum low-density lipoprotein cholesterol (LDL-c) are important risk factors of cardiovascular disease (CVD). It is recognized that regionalized adiposity has different cardiovascular risk, visceral versus subcutaneous, is a better predictor of CVD. However, the relationship between regionalized adiposity and LDL-c is unclear. The present study was designed to investigate the relationship between visceral fat accumulation and serum LDL-c levels in a Chinese cohort. Methods A total of 1 538 subjects (539 men, 999 women; 20–75 years old) with normal glucose tolerance and blood pressure were recruited. All subjects underwent magnetic resonance imaging to quantify visceral fat area (VFA) and subcutaneous fat area. Serum LDL-c levels were detected by direct assay method. Results Overweight/obese subjects (body mass index (BMI) ≥25 kg/m2) had significantly higher serum LDL-c levels than the lean subjects (BMI <25 kg/m2) (P<0.01). An increasing trend in serum LDL-c levels was found to accompany the increase in VFA (P for trend <0.01). Within the same BMI category, subjects with abdominal obesity (VFA ≥80 cm2) had significantly higher LDL-c levels than those without abdominal obesity (VFA <80 cm2) (P<0.05). Multiple stepwise regression analysis showed that increased VFA was an independent risk factor for elevated LDL-c levels, not only in the entire study population (Standard β = 0.138; P<0.01), but also when the study population was subdivided into men, premenopausal and postmenopausal women (Standard β = 0.117, 0.145, 0.090 respectively for men, premenopausal women, postmenopausal women; all P<0.01). Conclusions VFA was positively correlated with serum LDL-c levels in a nondiabetic Chinese population with normal blood pressure.

Associations of Serum Adipocyte Fatty Acid Binding Protein With Body Composition and Fat Distribution in Nondiabetic Chinese Women

CONTEXT Previous studies have demonstrated evidence of a positive relationship between serum adipocyte fatty acid binding protein (A-FABP) and obesity. However, associations of A-FABP with body composition and ectopic fat accumulation remain unclear. OBJECTIVE This study aimed to elucidate the effect of body composition, visceral fat area (VFA), and subcutaneous fat area (SFA) on serum A-FABP levels in a cohort of Chinese women without diabetes mellitus. DESIGN, SETTING, AND PARTICIPANTS A total of 2108 women without diabetes (760 premenopausal and 1348 postmenopausal women; age, 20-78 y) selected from the Shanghai Obesity Study were enrolled. MAIN OUTCOME MEASURES VFA and SFA were measured by magnetic resonance imaging, and body composition was determined by bioelectrical impedance analysis. A high VFA was defined as ≥ 80 cm(2). A high SFA was defined as that above the 75th percentile cutoff point of the menopause-specific population, respectively. RESULTS Serum A-FABP levels were higher in postmenopausal than premenopausal women (P < .001). Both premenopausal and postmenopausal women with an isolated high VFA had higher A-FABP levels than did those with an isolated high SFA (P = .017 and .002, respectively). In both body mass index (BMI) groups (< 25 and ≥ 25 kg/m(2)), women with a high VFA had higher serum A-FABP levels regardless of their menopausal status. Multiple stepwise regression analysis showed that A-FABP was independently associated with fat mass (Standardized β = 0.417 and 0.252 for premenopausal and postmenopausal status, respectively, both P < .001). Moreover, VFA was identified as an independent risk factor for A-FABP in postmenopausal women (Standardized β = 0.114, P = .001). Application of the same regression analyses model to the two BMI groups produced similar results in both BMI categories. CONCLUSIONS Serum A-FABP levels were associated with fat mass, and were also influenced by VFA after menopause in Chinese women without diabetes mellitus.

Association between serum osteocalcin level and visceral obesity in Chinese postmenopausal women

A low serum osteocalcin level, visceral obesity and postmenopausal status are recognized risk factors for cardiovascular disease.

Serum lipocalin-2 levels are positively associated with not only total body fat but also visceral fat area in Chinese men.

AbstractSerum lipocalin-2 (LCN2) plays an important role in the regulation of the obesity-associated dysmetabolic state and cardiovascular disease. However, relatively little is known about the relationship between serum LCN2 levels and body fat content and distribution. We examined the associations of total body fat content and abdominal fat distribution with serum LCN2 levels in Chinese men.The study was based on a cross-sectional analysis of data for 1203 Chinese men aged 22 to 78 years from the Shanghai Obesity Study. Body fat percentage (fat%) was assessed by bioelectrical impedance analysis, and magnetic resonance imaging was adopted to quantify the visceral fat area (VFA) and subcutaneous fat area (SFA). Serum levels of LCN2 were measured with a standard enzyme-linked immunosorbent assay method.Subjects with a high fat% had higher serum LCN2 levels than those with a normal fat% regardless of their body mass index category (<25 and ≥25 kg/m2). The frequency of isolated high VFA was increased with increasing quintiles of serum LCN2 levels (P < 0.001), but the frequency of isolated high SFA did not differ between quintiles of serum LCN2 levels. A trend of increasing VFA was observed with increasing serum LCN2 levels (P < 0.001). Multiple stepwise regression analysis showed that VFA was positively associated with serum LCN2 levels, independent of overall obesity and other confounding factors (standardized &bgr; = 0.082, P = 0.008).Serum LCN2 levels are positively correlated with body fat content and independently associated with VFA in Chinese men.

Contribution of maternal diabetes to visceral fat accumulation in offspring

BACKGROUND/OBJECTIVES Genetic and epidemiological studies provide evidence supporting the contribution of a genetic background of diabetes to the development of obesity and further suggest differences in the metabolic and cardiovascular risks between offspring with a paternal versus maternal family history of diabetes (FHD). The goal of this study was to explore the contribution of a parental FHD to visceral fat area (VFA). SUBJECTS/METHODS This study enrolled 1875 subjects with normal glucose tolerance (age range: 20-78 years). VFA was assessed with magnetic resonance imaging. RESULTS The study population consisted of 1573 subjects without a FHD, 115 subjects with a paternal FHD, and 187 subjects with a maternal FHD. For both genders, VFA was greater in offspring with a maternal FHD compared with those without a FHD (both P<0.05). For both genders, only VFA was an independent factor associated with a maternal FHD (both P<0.01). Compared with those without a FHD, men and women with a maternal FHD, but not those with a paternal FHD, were more likely to develop abdominal obesity (both P<0.05). After adjustment for independent factors related to VFA, VFA was increased by 9.60cm2 (standardized β=0.069, P=0.012) and 4.57cm2 (standardized β=0.056, P=0.007) in men and women with a maternal FHD, respectively. CONCLUSION A maternal FHD contributed to visceral fat accumulation independently in both genders. Maternal transmission had a pronounced effect on obesity and related cardiovascular risk factors.