Clinical significance of visceral fat reduction through health education in preventing atherosclerotic cardiovascular disease - Lesson from the Amagasaki Visceral Fat Study: A Japanese perspective. Nutr Metab (Lond). 2011;8:57. [PMID: 21846385 PMCID: PMC3199746 DOI: 10.1186/1743-7075-8-57]

Visceral fat loss by whole-body electromyostimulation is attenuated in male and absent in female older Non-Insulin-Dependent diabetes patients

INTRODUCTION

Type 2 diabetes and its reversal correlate with increases and decreases in visceral fat (VF). Resistance exercise reduces VF in healthy persons, but little is known in type 2 diabetes. Muscle contractions induced by whole-body electromyostimulation (WB-EMS) provide a very effective form of resistance training. We hypothesized that WB-EMS reduces VF and improves plasma glucose measures in older non-insulin dependent diabetes mellitus (NIDDM) males and females.

METHODS

A four-arm age-matched case control study was done on WB-EMS twice a week in older NIDDM patients (27 males, 18 females) compared with controls (15 males, 15 females). VAT area (VAT, cm² ), total fat mass (TFM, kg) and lean body mass (LBM, kg) were assessed by DEXA-scanning. HbA1c, fasting glucose and plasma lipoproteins were measured at baseline and after 4 months.

RESULTS

Baseline control VAT was higher in males than females (140.5 ± 35.6 vs. 96.7 ± 42.3, p < .001). In NIDDM, VAT was higher with no significant sex difference (206.5 ± 65.0 vs. 186.5 ± 60.5). In controls, WBEMS reduced VAT in males and females to similar extent (-16.9% and -16.4%, p < .001 vs. baseline) and in preference to TFM (-9.2% and -3.6%) or body weight loss (-2.8 and -2.1%). In NIDDM, VF loss was attenuated in males (-7.3%, p < .01) but completely absent in females. WBEMS reduced HbA1c and cholesterol and increased HDL levels (all p < .05) only in male NIDDM CONCLUSIONS: WBEMS induced VF loss in healthy older males and females an effect strongly attenuated in male and completely absent in female NIDDM patients. This questions the effectiveness of muscle contraction-induced VF lipolysis in NIDDM. Sex differences may dictate the success of resistance training in NIDDM, a subject that needs to be addressed in future studies.

Visceral obesity in Asian living kidney donors significantly impacts early renal function after donor nephrectomy

INTRODUCTION

Obesity may be a risk factor for kidney donors to develop reduced renal function. The Framingham heart study suggested that visceral adipose tissue (VAT) confers a more adverse metabolic profile compared with subcutaneous adipose tissue (SAT). Asians tend to have a higher VAT composition and it is unclear if their kidney function is affected differently. We hypothesized that Asian living kidney donors who have visceral obesity are at a higher risk of renal function deterioration 1 year after donation.

METHODS

Between 2011 and 2014, we retrospectively evaluated data from 73 consecutive patients (52% male; mean age 44.9 ± 11.7 years) before they underwent donor nephrectomy and at their 1 year routine follow-up. VAT and SAT were measured at the level of the umbilicus on pre-operative computerized tomography (CT). Visceral obesity (VO) was defined as a VAT > 100 cm [2] and patients were then further divided and compared in two subgroups: VAT > 100 and < 100 cm [2]. Estimated glomerular filtration rate (eGFR, mL/min per 1.73 m [2]) was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation pre-operatively and 1 year post-operatively.

RESULTS

Both subgroups had similar baseline kidney function (P = NS) pre-operatively. At the 1 year follow-up, patients with VO experienced a more significant decline of renal function (109 ± 9 to 89 ± 8 mL/min per 1.73 m²), compared to those without VO (111 ± 12 to 96 ± 11 mL/min per 1.73 m², P = 0.013). VO was associated with a body mass index (BMI) > 25 kg/m² (P < 0.001), male gender (P < 0.001) and older age at the time of donor nephrectomy (48.0 vs 39.5 years, P = 0.01). The presence of hypertension or hyperlipidaemia pre-operatively, choice of surgical approach, and post-operative complication rates, did not differ significantly between the subgroups.

CONCLUSIONS

Visceral obesity as defined by VAT > 100 cm² at the level of the umbilicus on cross-sectional imaging, may have a significant impact on early renal function after donor nephrectomy. Adiposity markers, as measured by cross-sectional CT imaging, may be incorporated into routine pre-operative kidney donor workup.

The relationship between the effect of matured hop extract and physical activity on reducing body fat: re-analysis of data from a randomized, double-blind, placebo-controlled parallel group study

BACKGROUND

We recently reported that successive ingestion of matured hop extract (MHE), produced by oxidation of hops, results in a reduction of body fat in healthy overweight participants. A combined effect of MHE and physical activity on body fat has not been investigated. Thus, we re-analyzed data from the previous study to explore the relationship between the effect of MHE and walking as an index of physical activity.

METHODS

This analysis uses existing data from a randomized, double-blind, placebo-controlled parallel group study in which MHE (active) or placebo was given for 12 w to 200 healthy overweight Japanese, from May to December 2014. Correlation between the change in abdominal fat areas at 12 w and the number of steps taken per day was tested by Spearman's correlation coefficient test. The subjects were stratified using the average number of steps per day of Japanese into walking less and walking more subgroups (WL and WM, respectively) as follows: placebo (WL, n = 43; WM, n = 44) and active (WL, n = 49; WM, n = 42). Reductions in total, visceral, and subcutaneous fat area (TFA, VFA and SFA, respectively) were evaluated. The interaction effect between ingestion (active/placebo) and walking (WL/WM) was analyzed using two-way analysis of variance (ANOVA).

RESULTS

There was a significant negative correlation between the change in VFA and daily steps taken in the active group (r = - 0.208, P = 0.048). No significant correlation in TFA or SFA. Although the interaction effect in TFA was not significant, the main effect of ingestion was significant (P = 0.045). In contrast, the interaction effect in VFA was suggested to be synergistic (P = 0.055).

CONCLUSION

The results suggested that MHE ingestion combined with light intensity exercise would induce a greater reduction in VFA which would be beneficial for obese or overweight individuals in reducing obesity and obesity-related diseases.

TRIAL REGISTRATION

UMIN-CTR UMIN000014185 registered 6 June 2014.

Effects of monthly feedback of VFA measured by dual BIA method in Japanese patients with obesity: a randomized controlled study

Objective

To investigate the effects of monthly feedback of changes in visceral fat area (VFA) as measured by dual bioelectrical impedance analysis method and the importance of VFA in individuals with obesity.

Methods

Thirty‐eight Japanese patients with obesity underwent VFA measurements. The feedback group was given feedback on VFA measurements each month for 4 months. The control group underwent VFA measurements at the beginning and end of the study but was not informed of the results. All the study participants completed eating behaviour and weight efficacy lifestyle questionnaires.

Results

Mean age was 53.9 (14.3) years; mean body mass index was 30.6 (4.3) kg m⁻². At the 4‐month follow‐up, there was no significant difference in VFA reduction between the control and feedback groups (−4.4% vs. −3.0%; 95% CI, −3.8 to 5.5). In post‐hoc analysis using the overall group irrespective of allocation, changes of eating style were significantly associated with a reduction in VFA at 4 months (p = 0.034).

Conclusions

Monthly feedback on changes in VFA does not reduce VFA. More frequent feedback may be required. In post‐hoc analysis, changes of eating style were associated with a reduction in VFA.

Clinical significance of visceral adiposity assessed by computed tomography: A Japanese perspective

Abdominal obesity, rather than total amount of fat, is linked to obesity-related disorders. Visceral adiposity is an important component of obesity-related disorders in Japanese individuals with a mild degree of adiposity compared with Western subjects. In 1983, our group reported techniques for body fat analysis using computed tomography (CT) and established the concept of visceral fat obesity in which intra-abdominal fat accumulation is an important factor in the development of obesity-related complications, such as diabetes, lipid disorders, hypertension and atherosclerosis. Our group also established ideal imaging conditions for determining abdominal fat area at the umbilical level CT scan. Visceral fat area (VFA) measured in a single slice at L4 level correlated significantly with the total abdominal visceral fat volume measured on multislice CT scan. In a large-scale study of a Japanese population, the mean number of obesity-related cardiovascular risk factors (hypertension, low high-density lipoprotein cholesterolemia and/or hypertriglyceridemia, and hyperglycemia) was greater than 1.0 at 100 cm² of VFA, irrespective of gender, age and body mass index. Our group also demonstrated that reduction of visceral fat accumulation subsequent to voluntary lifestyle modification, “Hokenshido”, correlated with a decrease in the number of obesity-related cardiovascular risk factors. It is important to select the most appropriate subjects from the general population (e.g., non-obese subjects with a cluster of risk factors for the metabolic syndrome) that are most suitable for body weight reduction, with the goal of preventing atherosclerotic cardiovascular diseases.

Short-term intervention reduces bioelectrical impedance analysis-measured visceral fat in type 2 diabetes mellitus

In 25 patients with Type 2 diabetes mellitus, the short-term in-hospital calorie restriction combined with moderate exercise reduced visceral fat. The reduction of visceral fat can improve metabolic cardiovascular risk factors, while the reductions in body weight and waist circumference were small and reduction in subcutaneous fat was not significant.

Substitution of TAG oil with diacylglycerol oil in food items improves the predicted 10 years cardiovascular risk score in healthy, overweight subjects

Dietary fat is normally in TAG form, but diacylglycerol (DAG) is a natural component of edible oils. Studies have shown that consumption of DAG results in metabolic characteristics that are distinct from those of TAG, which may be beneficial in preventing and managing obesity. The objective of the present study was to investigate if food items in which part of the TAG oil is replaced with DAG oil combined with high α-linolenic acid (ALA) content would influence metabolic markers. A 12-week double-blinded randomised controlled parallel-design study was conducted. The participants (n 23) were healthy, overweight men and women, aged 37–67 years, BMI 27–35 kg/m², with waist circumference >94 cm (men) and >88 cm (women). The two groups received 20 g margarine, 11 g mayonnaise and 12 g oil per d, containing either high ALA and sn-1,3-DAG or high ALA and TAG. Substitution of TAG oil with DAG oil in food items for 12 weeks led to an improvement of the predicted 10 years cardiovascular risk score in overweight subjects by non-significantly improving markers of health such as total body fat percentage, trunk fat mass, alanine aminotransferase, systolic blood pressure, γ-glutamyl transferase, alkaline phosphatase and total fat-free mass. This may suggest that replacing TAG oil with DAG oil in healthy, overweight individuals may have beneficial metabolic effects.

Reduction of visceral fat correlates with the decrease in the number of obesity-related cardiovascular risk factors in Japanese with Abdominal Obesity (VACATION-J Study)

AIM

Visceral fat accumulation is associated with obesity-related cardiovascular risk factor accumulation and atherosclerosis. The present study investigated whether one-year reduction of the visceral fat area (VFA) correlates with a decrease in the number of such factors in Japanese with or without visceral fat accumulation.

METHODS

The study subjects comprised 5,347 Japanese, who underwent health check-ups in 2007 and 2008, including measurements of VFA and subcutaneous fat area (SFA) by computed tomography at 9 centers in Japan. Subjects with one or more such factor(s) were categorized into tertiles based on the one-year change in VFA. We investigated the multivariate age, sex, and one-year change in SFA-adjusted odds ratios (ORs) and 95% confidence intervals (CI) for reductions in the number of risk factors in each of the three categories based on the one-year change in VFA, in subjects with one or more such factors (n= 3,648).

RESULTS

In the entire group (n=3,648), the OR and 95%CI for reductions in the number of risk factors in the first tertile were 0.804 (0.673-0.962, p=0.0172), compared with the second tertile set at 1.0. Subjects with VFA <100cm(2) showed no reduction in the number of risk factors. In subjects with VFA≥100 cm(2), OR in the first tertile was 0.788 (0.639-0.972, p=0.0257) relative to the second tertile set at 1.0.

CONCLUSIONS

In subjects with multiple cardiovascular risk factors, visceral fat reduction correlated with a decrease in the number of such factors in subjects with VFA≥100cm(2), but not in those with VFA<100cm(2).

Plasma leptin concentrations are greater in type II diabetic patients and stimulate monocyte chemotactic peptide-1 synthesis via the mitogen-activated protein kinase/extracellular signal-regulated kinase pathway

Background

Leptin is an adipokine that is recently reported to be a biomarker of systemic inflammation. Although atherosclerosis causes cardiovascular diseases, it is not clear whether leptin contributes to the acceleration of this process. In this study, we investigated whether alterations of plasma leptin levels were related to diabetic nephropathy and systemic inflammation. In addition, we examined the physiologic action of leptin in cultured vascular smooth muscle cells (VSMCs).

Methods

A total of 126 type 2 diabetic participants and 37 healthy controls were studied. The diabetic participants were divided into three groups according to stage of nephropathy. We investigated whether leptin induced monocyte chemotactic peptide-1 (MCP-1) synthesis through the mitogen-activated protein kinase (MAPK) pathway using cultured VSMCs.

Results

Plasma leptin concentrations were significantly higher in the diabetic group than in the controls. Plasma leptin levels were positively correlated with body mass index, fasting and postprandial blood glucose, hemoglobin A1c, total cholesterol, urinary albumin excretion, high-sensitivity C-reactive protein (hsCRP), and MCP-1 plasma levels, and negatively correlated with creatinine clearance values. In cultured VSMCs, leptin increased MCP-1 production in a dose-dependent manner, and this stimulating effect of leptin on MCP-1 expression was reversed by the MAPK (MEK) inhibitor PD98059. In addition, leptin stimulated the phosphorylation of MEK, extracellular signal–regulated kinase, and E26-like transcription factor, which are components of the MAPK pathway.

Conclusions

Overall, these findings suggest that activation of leptin synthesis may promote MCP-1 activation in a diabetic environment via the MAPK pathway in VSMCs and that it possibly contributes to the acceleration of atherosclerosis.

Cross-sectional and longitudinal study of association between circulating thiobarbituric acid-reacting substance levels and clinicobiochemical parameters in 1,178 middle-aged Japanese men - the Amagasaki Visceral Fat Study

Background

Circulating thiobarbituric acid-reacting substance (TBARS) levels, a marker of systemic oxidative stress, are predictive of cardiovascular events. However, they has not been evaluated in Japanese, especially with regard to the factors that contribute to the changes in circulating TBARS levels. We investigated the cross-sectional and longitudinal relationships between circulating TBARS levels and various clinicobiochemical parameters in middle-aged men.

Methods

In this population-based study (The Amagasaki Visceral Fat Study), 1,178 Japanese male urban workers who had undergone health check-ups in 2006, 2007 and 2008 and were not on medications for metabolic disorders during the follow-up period, were enrolled. Serum TBARS levels were measured by the method of Yagi. The estimated visceral fat area (eVFA) by bioelectrical impedance was measured annually. After health check-ups, subjects received health education with lifestyle modification by medical personnel.

Results

The number of cardiovascular risk factors (hypertension, hyperglycemia, low HDL-C, hypertriglyceridemia, hyperuricemia, hyper-LDL-C and impaired renal function) augmented with the increases in log-eVFA (p < 0.0001) and log-TBARS (p < 0.0001). The combination of TBARS and eVFA had a multiplicative effect on risk factor accumulation (F value = 79.1, p = 0.0065). Stepwise multiple regression analysis identified log-eVFA, as well as age, log-body mass index (BMI), LDL-C, log-adiponectin, γ-glutamyl transpeptidase (γ-GTP) and uric acid as significant determinants of log-TBARS. Stepwise multiple regression analysis identified one-year changes in eVFA as well as BMI, γ-GTP and estimated glomerular filtration rate (eGFR) as significant determinants of one-year change in TBARS, and biennial changes in eVFA as well as BMI and γ-GTP, eGFR as significant determinants of biennial change in TBARS.

Conclusions

The present study showed a significant cross-sectional and longitudinal correlation between TBARS and eVFA, as well as BMI and γ- GTP, eGFR. Visceral fat reduction may independently associate with the improvement in systemic ROS in middle-aged Japanese men.

Trial Registration

The Amagasaki Visceral Fat Study UMIN000002391.