Aki Hiuge-Shimizu

Absolute value of visceral fat area measured on computed tomography scans and obesity-related cardiovascular risk factors in large-scale Japanese general population (the VACATION-J study)

Abstract Background. The management of cardiovascular risk factors is important for prevention of atherosclerotic cardiovascular diseases (ACVD). Visceral fat accumulation plays an important role in the clustering of cardiovascular risk factors, leading to ACVD. The present study investigated the gender- and age-specific relationship between obesity-related cardiovascular risk factor accumulation and computed tomography (CT)-measured fat distribution in a large-scale Japanese general population. Methods and results. Fat distribution was measured on CT scans in 12,443 subjects (males/females = 10,080/2,363), who underwent medical health check-up at 9 centers in Japan. The investigated obesity-related cardiovascular risk factors were hyperglycemia, dyslipidemia, and elevated blood pressure. Visceral fat area (VFA) for all males and old females showed almost symmetric distribution, while that of young females showed skewed distribution with a marked left shift. Only a small proportion of young females had large visceral fat and cardiovascular risk accumulation. The mean number of risk factors exceeded 1.0 at around 100 cm2 for VFA in all groups, irrespective of gender, age (cut-off age 55), and BMI (cut-off BMI 25 kg/m2). Conclusions. In this large-scale Japan-wide general population study, an absolute VFA value of about 100 cm2 equated with obesity-related cardiovascular risk factor accumulation, irrespective of gender, age, and BMI. Clinical trial registration information. https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=brows&action=brows&type=summary&recptno=R000002780&language=E.

Short-term effects of liraglutide on visceral fat adiposity, appetite, and food preference: a pilot study of obese Japanese patients with type 2 diabetes

BackgroundTo examine the effects of liraglutide, a glucagon-like peptide-1 (GLP-1) analogue, on visceral fat adiposity, appetite, food preference, and biomarkers of cardiovascular system in Japanese patients with type 2 diabetes.MethodsThe study subjects were 20 inpatients with type 2 diabetes treated with liraglutide [age; 61.2 ± 14.0 years, duration of diabetes; 16.9 ± 6.6 years, glycated hemoglobin (HbA1c); 9.1 ± 1.2%, body mass index (BMI); 28.3 ± 5.2 kg/m2, mean ± SD]. After improvement in glycemic control by insulin or oral glucose-lowering agents, patients were switched to liraglutide. We assessed the estimated visceral fat area (eVFA) by abdominal bioelectrical impedance analysis, glycemic control by the 75-g oral glucose tolerance test (OGTT) and eating behavior by the Japan Society for the Study of Obesity questionnaire.ResultsTreatment with liraglutide (dose range: 0.3 to 0.9 mg/day) for 20.0 ± 6.4 days significantly reduced waist circumference, waist/hip ratio, eVFA. It also significantly improved the scores of eating behavior, food preference and the urge for fat intake and tended to reduce scores for sense of hunger. Liraglutide increased serum C-peptide immunoreactivity and disposition index.ConclusionsShort-term treatment with liraglutide improved visceral fat adiposity, appetite, food preference and the urge for fat intake in obese Japanese patients with type 2 diabetes.

Contribution of glucocorticoid-mineralocorticoid receptor pathway on the obesity-related adipocyte dysfunction.

AIMS Mineralocorticoid receptor (MR) blockade ameliorated insulin resistance with improvements in adipocytokine dysregulation, inflammation, and excess of reactive oxygen species (ROS) in obese adipose tissue and adipocytes, but its mechanism has not been clarified. The 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), producing active glucocorticoids, is highly expressed in adipocytes and glucocorticoids bind to MR with higher affinity than to glucocorticoid receptor (GR). We investigated whether glucocorticoids effect on adipocytokines and ROS through MR in adipocytes. In addition, fat distributions of MR and GR were investigated in human subjects. METHODS AND RESULTS Corticoid receptors and their target genes were examined in adipose tissue of obese db/db mice. 3T3-L1 adipocytes were treated with glucocorticoids, H(2)O(2), MR antagonist eplerenone (EP), GR antagonist RU486 (RU), MR-siRNA, and/or N-acetylcysteine. Human adipose tissues were obtained from seven patients who underwent abdominal surgery. The mRNA levels of MR and its target gene were higher in db/db mice than in control db/m+mice. In 3T3-L1 adipocytes, glucocorticoids, similar to H(2)O(2), caused the dysregulation of mRNA levels of various genes related to adipocytokines and the increase of intracellular ROS. Such changes were rectified by MR blockade, not by GR antagonist. In human fat, MR mRNA level was increased in parallel with the increase of body mass index (BMI) and its increase was more significant in visceral fat, while there were no apparent correlations of GR mRNA level to BMI or fat distribution. CONCLUSION Glucocorticoid-MR pathway may contribute to the obesity-related adipocytokine dysregulation and adipose ROS.

Dynamic Changes of Adiponectin and S100A8 Levels by the Selective Peroxisome Proliferator–Activated Receptor-γ Agonist Rivoglitazone

Objective—Accumulating evidence indicates that the regimen to increase adiponectin will provide a novel therapeutic strategy for metabolic syndrome. Here, we tested the effect of a potent and selective peroxisome proliferator–activated receptor-&ggr; agonist, rivoglitazone (Rivo), a newly synthesized thiazolidinedione derivative, on adiponectin, insulin resistance, and atherosclerosis. Methods and Results—ob/ob mice, apolipoprotein E knockout (apoE KO) mice, and apoE and adiponectin double knockout mice were administered pioglitazone, Rivo, or no compound. Remarkable elevation of plasma adiponectin was observed, especially in Rivo-treated ob/ob mice. Rivo ameliorated insulin resistance in ob/ob mice and reduced atherosclerotic areas in apoE KO mice compared with the pioglitazone group but failed to decrease atherosclerotic areas in double knockout mice. Among adipose mRNAs, adipose S100A8, which activates Toll-like receptor 4–dependent signal transduction cascades and locates upstream of inflammation, was markedly increased in ob/ob mice, and its increase was completely reversed by Rivo treatment. In RAW264.7 macrophage cells and 3T3-L1 adipocytes, Rivo significantly reduced S100A8 mRNA levels. Conclusion—The peroxisome proliferator–activated receptor-&ggr; agonist Rivo remarkably enhanced adiponectin in plasma and decreased adipose S100A8 mRNA levels in obese mice. Rivo treatment apparently ameliorated insulin resistance in ob/ob mice and reduced atherosclerosis in apoE KO mice, partly through adiponectin.

A Pilot Investigation of Visceral Fat Adiposity and Gene Expression Profile in Peripheral Blood Cells

Evidence suggests that visceral fat accumulation plays a central role in the development of metabolic syndrome. Excess visceral fat causes local chronic low-grade inflammation and dysregulation of adipocytokines, which contribute in the pathogenesis of the metabolic syndrome. These changes may affect the gene expression in peripheral blood cells. This study for the first time examined the association between visceral fat adiposity and gene expression profile in peripheral blood cells. The gene expression profile was analyzed in peripheral blood cells from 28 obese subjects by microarray analysis. Reverse transcription-polymerase chain reaction (RT-PCR) was performed using peripheral blood cells from 57 obese subjects. Obesity was defined as body mass index (BMI) greater than 25 kg/m2 according to the Japanese criteria, and the estimated visceral fat area (eVFA) was measured by abdominal bioelectrical impedance. Analysis of gene expression profile was carried out with Agilent whole human genome 4×44 K oligo-DNA microarray. The expression of several genes related to circadian rhythm, inflammation, and oxidative stress correlated significantly with visceral fat accumulation. Period homolog 1 (PER1) mRNA level in blood cells correlated negatively with visceral fat adiposity. Stepwise multiple regression analysis identified eVFA as a significant determinant of PER1 expression. In conclusion, visceral fat adiposity correlated with the expression of genes related to circadian rhythm and inflammation in peripheral blood cells.

High prevalence of gastroesophageal reflux symptoms in type 2 diabetics with hypoadiponectinemia and metabolic syndrome

BackgroundThe prevalence of gastroesophageal reflux disease (GERD) has been increasing worldwide. Abdominal obesity or visceral fat accumulation rather than simple obesity is associated with GERD. Previous reports demonstrated the association between GERD and type 2 diabetes mellitus (T2DM). Signification of visceral fat accumulation and adiponectin in T2DM patients with GERD remains unclear. The present study investigated the relationships between GERD symptoms, visceral fat accumulation and adiponectin in subjects with T2DM.FindingsThe study (ADMIT study) subjects were 66 Japanese T2DM outpatients, who answered the questionnaire regarding GERD symptoms in Frequency Scale for the Symptoms of GERD (FSSG), and were measured visceral fat area by bioelectrical impedance analysis. Patients with FSSG scores of more than 8 were considered as positive. The prevalence of FSSG score ≥ 8 and average FSSG score in T2DM subjects with the metabolic syndrome (Mets) were significantly higher compared to those without Mets. The prevalence of FSSG score ≥ 8 and average FSSG score in T2DM subjects with low levels of serum adiponectin were significantly higher compared to those with high levels of serum adiponectin. Moreover, the combination of Mets and hypoadiponectinemia had a multiplicative effect on GERD symptom score (p = 0.047).ConclusionsOur study showed that the coexistence of MetS and low levels of serum adiponectin was associated with the higher prevalence of FSSG score ≥ 8 and the higher scores of GERD symptom in subjects with T2DM.Trial RegistrationUMIN 000002271.

High serum S100A8/A9 levels and high cardiovascular complication rate in type 2 diabetics with ultrasonographic low carotid plaque density

AIMS S100A8/A9 complex is an inflammation-associated biomarker, which binds toll-like receptor 4 and was associated with the receptor for advanced glycation end-products. S100A8 and S100A9 were accumulated in atherosclerotic lesions. High serum levels of S100A8/A9 are associated with acute coronary syndrome and atherosclerosis in type 2 diabetes mellitus (T2DM). However, association between serum S100A8/A9 levels and vulnerable plaque remains unclear. The present study investigated the relation between serum S100A8/A9 levels and relative plaque density (RPD) of the carotid artery determined by ultrasonography in T2DM. METHODS The study subjects were 72 consecutive T2DM outpatients (males/females=42/30), who underwent the carotid artery ultrasonography. RPD in the carotid artery was calculated by the formula; RPD=[density of the carotid plaque/density of vessel lumen]. Serum levels of adiponectin and S100A8/A9 were measured. RESULTS The median RPD was 2.1. Patients with low RPD (≤2.1) were significantly more likely to have metabolic syndrome, nephropathy, coronary artery disease, and peripheral artery disease, and higher levels of S100A8/A9, S100A8/A9-to-adiponectin ratio, and uric acid, compared to those with high RPD (>2.1). CONCLUSIONS T2DM patients with low RPD had higher prevalence of metabolic syndrome, cardiovascular diseases and higher serum S100A8/A9 levels, compared to those with high RPD.

Qualitative score of systemic arteriosclerosis by vascular ultrasonography as a predictor of coronary artery disease in type 2 diabetes.

OBJECTIVE Patients with type 2 diabetes mellitus (T2DM) are at risk of polyvascular comorbidities and poor prognosis. Non-invasive techniques for early prediction of coronary artery disease (CAD) are desirable to prevent cardiovascular events in these patients. The aim of the present study was to investigate the association between CAD and systemic arteriosclerosis by qualitative vascular ultrasonography. METHODS The study subjects were 102 consecutive outpatients with T2DM [males/females = 60/42, age: mean ± SD 67 ± 9 (range, 40-85) years] evaluated by vascular ultrasonography for arteriosclerosis in the abdominal aorta, carotid, renal, and common iliac arteries. The total number of detected arteriosclerotic vascular lesions in the four arteries was determined. CAD was diagnosed by two cardiologists using either stress electrocardiography, myocardial scintigraphy, multi-detector row computed tomography or coronary angiography. RESULTS Multiple arteriosclerotic vascular lesions (>1) were detected in 64 (63%) patients. The total systemic vascular score was significantly higher in patients with CAD than those without (average score 2.7 versus 1.0, p < 0.0001). None of the CAD patients had a total score of 0. Age- and sex-adjusted multiple logistic regression analysis identified total score of ≥ 2 as the only predictor of CAD (p < 0.001). The sensitivity, specificity, positive and negative predictive values for total systemic vascular score in the prediction of CAD were 98%, 77%, 83%, and 97%, respectively, which were better than those for carotid mean and maximum intima-media thickness. CONCLUSION Non-invasive qualitative evaluation of systemic arteriosclerosis by the total systemic vascular score is potentially useful for the early prediction of CAD in T2DM patients.

Metabolic syndrome correlates with polyvascular lesions detected by systemic vascular ultrasonography in Japanese people with type 2 diabetes

Atherosclerosis is a systemic disease of blood vessels. We investigated clinical characteristics of Japanese type 2 diabetic patients with polyvascular lesions detected by systemic vascular ultrasonography. The results showed that the metabolic syndrome correlated with polyvascular lesions detected by systemic vascular ultrasonography in Japanese type 2 diabetics.