Adiponectin plays a role as a positive contributor to the stabilization of atherosclerotic plaques. Circulating total adiponectin (Total-APN) levels associates with the number of coronary vessels in men with coronary artery disease (CAD). We recently reported that adiponectin binds to C1q in human blood, and serum C1q-binding adiponectin (C1q-APN) /Total-APN levels are associated with CAD in type 2 diabetic subjects. The present study investigated the relationship between circulating C1q-APN levels and the number of angiographic coronary artery vessel in male subjects.
The study subjects were 53 male Japanese patients who underwent diagnostic coronary angiography. Blood total adiponectin (Total-APN), high-molecular weight adiponectin (HMW-APN), C1q-APN and C1q were measured by enzyme-linked immunosorbent assays.
Serum C1q-APN/Total-APN ratio significantly increased in subjects with single and multi-vessel coronary diseases (p = 0.029 for trend, the Kruskal-Wallis test). However, serum Total-APN, HMW-APN, C1q-APN and C1q levels did not correlate with number of diseased coronary vessels.
Serum C1q-APN/Total-APN ratio progressively increases in men with single and multi-vessel coronary disease.
Adiponectin; C1q; C1q-binding adiponectin; Coronary artery disease; Angiographic coronary vessel
The dipeptidyl-peptidase-IV (DPP-4) inhibitors, including sitagliptin, are used for the treatment of type 2 diabetes mellitus (T2DM). Adiponectin, an adipocyte-derived circulating protein, has anti-atherosclerotic and anti-diabetic properties and is effectively elevated in bloodstream by thiazolidinediones, an insulin sensitizer. However, the effect of sitagliptin treatment on serum adiponectin level in T2DM has not fully elucidated in Japanese T2DM patients. The aim of the present study was to examine the effect of sitagliptin treatment on serum adiponectin levels in T2DM subjects.
Twenty-six consecutive Japanese T2DM outpatients were recruited between April 2011 and March 2013, and randomized into the control (conventional treatment, n = 10) group and sitagliptin treatment group (n = 16). Serum adiponectin was measured by enzyme-linked immunosorbent assay.
Indices of glycemic control, such as hemoglobin A1c, glycated albumin, and 1.5-anhydro-D-glucitol, were significantly improved after the three-month treatment in both the control and sitagliptin groups. Serum adiponectin level was significantly increased in sitagliptin group from 6.7 ± 0.8 to 7.4 ± 1.0 μg/mL without change of body mass index (p = 0.034), while serum adiponectin level was not altered in the control group (p = 0.601).
In Japanese T2DM patients, serum adiponectin level was elevated by three-month treatment with sitagliptin without change of body weight.
Sitagliptin; Adiponectin; DPP4 inhibitor; Inctrein; Diabetes; Oxidative stress
Adiponectin, adipose-specific secretory protein, abundantly circulates in bloodstream and its concentration is around 1000-fold higher than that of other cytokines and hormones. Hypoadiponectinemia is a risk factor for atherosclerosis. There is little or no information on ultrastructural localization of adiponectin in the vasculature. Herein we investigated the localization of vascular adiponectin in the aorta using the immunoelectron microscopic technique. In wild-type (WT) mice, adiponectin was mainly detected on the luminal surface membrane of endothelial cells (ECs) and also found intracellularly in the endocytic vesicles of ECs. In the atherosclerotic lesions of apolipoprotein E-knockout (ApoE-KO) mice, adiponectin was detected in ECs, on the cell surface membrane of synthetic smooth muscle cells, and on the surface of monocytes adherent to ECs. Changes in adiponectin localization within the wall of the aorta may provide novel insight into the pathogenesis of atherosclerosis.
To establish the validity of the plasma glucose disappearance rate (KITT), derived from an insulin‐tolerance test (ITT), for evaluating the insulin sensitivity of patients with type 2 diabetes after insulin therapy.
Materials and Methods
In the first arm of the study, 19 patients with poorly controlled diabetes were treated with insulin and underwent an ITT and a euglycemic clamp test (clamp‐IR). The relationship between the insulin resistance index, as assessed by both the clamp‐IR and KITT tests, was examined. In the second arm of the study, the relationships between KITT values and various clinical parameters were investigated in 135 patients with poorly controlled diabetes, after achieving glycemic control with insulin.
In study 1, a close correlation between KITT and the average glucose infusion rate during the last 30 min of the standard clamp‐IR test (M‐value) was noted (P < 0.001). In study 2, body mass index (P = 0.0011), waist circumference (P = 0.0004), visceral fat area (P = 0.0011) and the log‐transformed homeostasis model assessment of insulin resistance value (P = 0.0003) were negatively correlated with the log‐transformed KITT. High‐density lipoprotein cholesterol (P = 0.0183), low‐density lipoprotein cholesterol (P = 0.0121) and adiponectin (P = 0.0384) levels were positively correlated with the log‐transformed KITT.
The ITT is a valid and useful test for evaluating the insulin sensitivity of patients with diabetes, even after treatment with insulin.
Insulin resistance; Insulin therapy; Insulin tolerance test
•We generated a hetero parabiosis model of wild type and adiponectin knockout (KO) mice.•Adiponectin protein was detected in adipose tissues of the KO parabiotic partner.•High adiponectin levels were found in stromal vascular fraction of the obese KO partner.•Obese parabiotic mice exhibited marked hypoadiponectinemia.
Adiponectin is exclusively synthesized by adipocytes and exhibits anti-diabetic, anti-atherosclerotic and anti-inflammatory properties. Hypoadiponectinemia is associated in obese individuals with insulin resistance and atherosclerosis. However, the mechanisms responsible for hypoadiponectinemia remain unclear. Here, we investigated adiponectin movement using hetero parabiosis model of wild type (WT) and adiponectin-deficient (KO) mice. WT mice were parabiosed with WT mice (WT–WT) or KO mice (WT–KO) and adiponectin levels were measured serially up to 63 days after surgery. In the WT–KO parabiosis model, circulating adiponectin levels of the WT partners decreased rapidly, on the other hand, those of KO partners increased, and then these reached comparable levels each other at day 7. Circulating adiponectin levels decreased further to the detection limit of assay, and remained low up to day 63. However, adiponectin protein was detected in the adipose tissues of not only the WT partner but also WT–KO mice. In the diet-induced obesity model, high adiponectin protein levels were detected in adipose stromal vascular fraction of diet-induced obese KO partner, without changes in its binding proteins. The use of parabiosis experiments shed light on movement of native adiponectin among different tissues such as the state of hypoadiponectinemia in obesity.
APN, adiponectin; KO, adiponectin deficient mice; HF/HS, high fat/high sucrose diet; KO (WT–KO), KO partner of WT–KO; MAF, mature adipocyte fraction; NC, normal chow diet; SVF, stromal vascular fraction; WATmes, mesenteric white adipose tissue; WATsub, subcutaneous white adipose tissue; WT (WT–KO), WT partner of WT–KO; WT (WT–WT), WT partner of WT–WT; WT, wild type mice; WT–KO, parabiosis between WT and KO; WT–WT, parabiosis between WT and WT; Adiponectin; Adipose tissue; Obesity; Parabiosis
Obesity is an epidemic matter increasing risk for cardiovascular diseases and metabolic disorders such as type 2 diabetes. We recently examined the association between visceral fat adiposity and gene expression profile of peripheral blood cells in human subjects. In a series of studies, Opa (Neisseria gonorrhoeae opacity-associated)-interacting protein 5 (OIP5) was nominated as a molecule of unknown function in adipocytes and thus the present study was performed to investigate the role of OIP5 in obesity. Adenovirus overexpressing Oip5 (Ad-Oip5) was generated and infected to 3T3-L1 cells stably expressing Coxsackie-Adenovirus Receptor (CAR-3T3-L1) and to mouse subcutaneous fat. For a knockdown experiment, siRNA against Oip5 (Oip5-siRNA) was introduced into 3T3-L1 cells. Proliferation of adipose cells was measured by BrdU uptake, EdU-staining, and cell count. Significant increase of Oip5 mRNA level was observed in obese white adipose tissues and such increase was detected in both mature adipocytes fraction and stromal vascular cell fraction. Ad-Oip5-infected CAR-3T3-L1 preadipocytes and adipocytes proliferated rapidly, while a significant reduction of proliferation was observed in Oip5-siRNA-introduced 3T3-L1 preadipocytes. Fat weight and number of adipocytes were significantly increased in Ad-Oip5-administered fat tissues. Oip5 promotes proliferation of pre- and mature-adipocytes and contributes adipose hyperplasia. Increase of Oip5 may associate with development of obesity.
The complement system is part of the immune system in acute coronary syndrome (ACS). Adiponectin has anti-atherogenic and anti-inflammatory properties. Adiponectin and C1q form a protein complex in blood, and serum C1q binding adiponectin (C1q-APN) can be measured. We investigated the comparative evaluation of serum C1q-APN levels in males with ACS, stable angina pectoris (SAP) versus controls.
The study subjects were 138 Japanese patients who underwent diagnostic coronary angiography. Blood total adiponectin (Total-APN), C1q-APN and C1q were measured by enzyme-linked immunosorbent assays. Patients were divided into three groups according to the clinical condition: ACS (n = 78), SAP (n = 41) or normal coronary (NC, n = 19) groups.
Serum C1q levels were significantly higher in the ACS group (54.9±1.2 μg/mL) than in the NC group (48.0±2.5 μg/mL). Although serum Total-APN levels were significantly lower in the SAP and ACS groups, compared with the NC group (7.0±0.5, 7.2±0.3, 10.6±2.0 μg/mL, respectively), serum C1q-APN levels were significantly higher in the ACS group than in the NC and SAP groups (112.1±4.1, 66.3±4.4, 65.7±2.9 units/mL, respectively).
Patients with ACS had higher serum C1q-APN levels.
Adiponectin; C1q; C1q-binding adiponectin; Acute coronary syndrome
Ephrin-B1 (EfnB1) was selected among genes of unknown function in adipocytes or adipose tissue and subjected to thorough analysis to understand its role in the development of obesity.
Methods and Results
EfnB1 mRNA and protein levels were significantly decreased in adipose tissues of obese mice and such reduction was mainly observed in mature adipocytes. Exposure of 3T3-L1 adipocytes to tumor necrosis factor-α (TNF-α) and their culture with RAW264.7 cells reduced EFNB1 levels. Knockdown of adipose EFNB1 increased monocyte chemoattractant protein-1 (Mcp-1) mRNA level and augmented the TNF-α-mediated THP-1 monocyte adhesion to adipocytes. Adenovirus-mediated adipose EFNB1-overexpression significantly reduced the increase in Mcp-1 mRNA level induced by coculture of 3T3-L1 adipocytes with RAW264.7 cells. Monocyte adherent assay showed that adipose EfnB1-overexpression significantly decreased the increase of monocyte adhesion by coculture with RAW264.7 cells. TNF-α-induced activation of extracellular signal-regulated kinase 1/2 (ERK1/2) was reduced by EFNB1-overexpression.
EFNB1 contributes to the suppression of adipose inflammatory response. In obesity, reduction of adipose EFNB1 may accelerate the vicious cycle involved in adipose tissue inflammation.
The aim of the present study was to determine whether weight reduction is associated with improvement of glycemic control in non‐obese and obese subjects with or without visceral fat accumulation, whose hemoglobin A1c (A1C) is 5.6–6.4%.
Materials and Methods
A total of 798 male subjects whose A1C levels were between 5.6% and 6.4% were divided into subgroups based on body mass index (BMI) and/or estimated visceral fat area (eVFA), and were analyzed with respect to the relationships between 1‐year changes in BMI (ΔBMI) and A1C (ΔA1C).
In both the BMI ≥25 and BMI <25 groups, ΔA1C correlated positively with ΔBMI (BMI ≥25 (n = 321): r = 0.236, P < 0.0001; BMI <25 (n = 477): r = 0.095, P = 0.0387) although the r‐value was very small for the latter group. In addition, for the group with eVFA ≥100 cm2 (n = 436), ΔA1C correlated positively with ΔeVFA (r = 0.150, P = 0.0017), but this correlation was not found for the eVFA <100 cm2 group (n = 339, P = 0.3505). Furthermore, ΔA1C positively correlated with ΔBMI for the groups in BMI ≥25 with eVFA >100 cm2 (n = 293, r = 0.256, P < 0.0001) and BMI <25 with eVFA ≥100 cm2 (n = 145, r = 0.250, P = 0.0024), but not for the groups in BMI ≥25 with eVFA <100 cm2 (n = 28, P = 0.6401) nor BMI <25 with eVFA <100 cm2 (n = 332, P = 0.6605).
These results suggest that the assessment of visceral fat, rather than BMI, might be more important in identifying subjects in whom lifestyle intervention aiming at weight reduction could be effective to prevent diabetes. This trial was registered with University Hospital Medical Information Network Clinical Trials Registry (no. UMIN 000002391).
Glycemic control; Visceral fat accumulation; Weight reduction
Inflammation is closely associated with the development of atherosclerosis and metabolic syndrome. Adiponectin, an adipose-derived secretory protein, possesses an anti-atherosclerotic property. The present study was undertaken to elucidate the presence and significance of adiponectin in vasculature.
Methods and Results
Immunofluorescence staining was performed in aorta of wild-type (WT) mice and demonstrated that adiponectin was co-stained with CD31. Thoracic aorta was cut through and then aortic intima was carefully shaved from aorta. Western blotting showed the existence of adiponectin protein in aortic intima, while there was no adiponectin mRNA expression. Adiponectin knockout (Adipo-KO) and WT mice were administered with a low-dose and short-term lipopolysaccharide (LPS) (1 mg/kg of LPS for 4 hours). The endothelium vascular adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) were highly increased in Adipo-KO mice compared to WT mice after LPS administration.
Adiponectin protein exists in aortic endothelium under steady state and may protect vasculature from the initiation of atherosclerosis.
Although many Asian type 2 diabetic patients have been considered to be not obese and have low capacity of insulin secretion, the proportion of obese patients with visceral fat accumulation has increased in recent years. We found previously considerable number of Japanese non-obese subjects (body mass index (BMI) < 25 kg/m2) with visceral fat accumulation and multiple cardiovascular risk factors. The aim of the study was to investigate the difference in clinical features of type 2 diabetic patients with and without visceral fat accumulation, focusing on vascular complications and changes in BMI.
We enrolled 88 Japanese hospitalized type 2 diabetic patients. Abdominal obesity represented waist circumference (WC) of ≥85 cm for males and ≥90 cm for females (corresponding to visceral fat area of 100 cm2). Subjects were divided into two groups; with or without abdominal obesity.
Hypertension, dyslipidemia and cardiovascular diseases were significantly more in the patients with abdominal obesity. The prevalence of cardiovascular disease in the non-obese patients (BMI < 25 kg/m2) with abdominal obesity were similar in obese patients (BMI ≥25 kg/m2). The mean BMI of the patients with abdominal obesity was < 25 kg/m2 at 20 years of age, but reached maximum to more than 30 kg/m2 in the course. Furthermore, substantial portion of the type 2 diabetic patients (52% in males and 43% in females) were not obese at 20 year-old (BMI < 25 kg/m2), but developed abdominal obesity by the time of admission.
These results emphasize the need to control multiple risk factors and prevent atherosclerotic disease in patients with abdominal obesity. The significant weight gain after 20 years of age in patients with abdominal obesity stresses the importance of lifestyle modification in younger generation, to prevent potential development of type 2 diabetes and future atherosclerotic cardiovascular disease.
Abdominal obesity; Type 2 diabetes; Waist circumference; Visceral fat accumulation; Body mass index; Cardiovascular disease
Atherosclerosis is an age-related disease. Adiponectin and C1q form a protein complex in human blood, and that serum C1q and C1q-binding adiponectin (C1q-APN) concentrations can be measured. We investigated circulating C1q and C1q-APN levels in Japanese men including elderly men.
The study subjects were 509 Japanese men including elderly men. Serum levels of total adiponectin (Total-APN), high-molecular weight-adiponectin (HMW-APN), C1q-APN and C1q were measured by enzyme-linked immunosorbent assay. Total-APN, HMW-APN and C1q-APN, but not C1q, correlated significantly and positively with aging (r=0.26, r=0.24, r=0.17, p<0.01, respectively). The HMW-APN/Total-APN ratio correlated significantly and positively with aging (r=0.14, p<0.01). The C1q-APN/Total-APN ratio and C1q-APN/HMW-APN ratio correlated significantly and negatively with aging (r=−0.17, p<0.01, r=−0.12, p=0.01). C1q-APN/C1q correlated significantly and positively with aging (r=0.09, p=0.03). Multiple regression analysis identified age and body mass index as significant determinants of C1q-APN.
The present study demonstrates that serum HMW-APN, C1q-APN, and Total-APN, but not C1q, correlated positively with aging. These preliminary results could form the basis for future research.
Clinical Trial Registration Number: UMIN000004318
Adiponectin; C1q; C1q-binding adiponectin; Aging
Recently, dipeptidyl peptidase‐4 (DPP‐4) inhibitors have become available in Japan. It has not yet been clarified what clinical parameters could discriminate DPP‐4 inhibitor‐effective patients from DPP‐4 inhibitor‐ineffective patients.
Materials and Methods
We reviewed 33 consecutive patients with type 2 diabetes admitted to Osaka University Hospital for glycemic control. All of the patients were treated with medical nutrition therapy plus insulin therapy to improve fasting plasma glucose (FPG) and postprandial glucose below 150 and 200 mg/dL, respectively. After insulin secretion and insulin resistance were evaluated, insulin was replaced by DPP‐4 inhibitors. The efficacy of DPP‐4 inhibitors was determined according to whether glycemic control was maintained at the target levels.
Dipeptidyl peptidase‐4 inhibitors were effective in 16 of 33 patients. DPP‐4 inhibitor‐effective patients were younger than DPP‐4 inhibitor‐ineffective patients. Body mass index (BMI) was significantly higher in DPP‐4 inhibitor‐effective patients. Endogeneous insulin‐secreting capacity, including insulinogenic index (II), fasting plasma C‐peptide (F‐CPR) and C‐peptide index (CPI), was more sustained in DPP‐4 inhibitor‐effective patients than DPP‐4 inhibitor‐ineffective patients. Insulin resistance evaluated by homeostasis model assessment of insulin resistance (HOMA‐IR) was significantly higher in DPP‐4 inhibitor‐effective patients than DPP‐4 inhibitor‐ineffective patients. In receiver operating characteristic analyses, the cut‐off values for predicting the efficacy of DPP‐4 inhibitors were 0.07 for II, 1.5 ng/mL for F‐CPR, 1.0 for CPI, 23.0 kg/m2 for BMI, 1.3 for HOMA‐IR and 67.5 years for age.
Dipeptidyl peptidase‐4 inhibitors were effective in Japanese type 2 diabetic patients with sustained endogenous insulin‐secreting capacity, a higher BMI and insulin resistance.
Dipeptidyl peptidase‐4 inhibitor; Insulin secretion; Type 2 diabetes
Visceral fat accumulation is caused by over-nutrition and physical inactivity. Excess accumulation of visceral fat associates with atherosclerosis. Polyunsaturated fatty acids have an important role in human nutrition, but imbalance of dietary long-chain polyunsaturated fatty acids, especially low eicosapentaenoic acid (EPA) / arachidonic acid (AA) ratio, is associated with increased risk of cardiovascular disease. The present study investigated the correlation between EPA, docosahexaenoic acid (DHA), AA parameters and clinical features in male subjects.
The study subjects were 134 Japanese with diabetes, hypertension and/or dyslipidemia who underwent measurement of visceral fat area (eVFA) by the bioelectrical impedance method and serum levels of EPA, DHA and AA. EPA/AA ratio correlated positively with age, and negatively with waist circumference and eVFA. Stepwise regression analysis demonstrated that age and eVFA correlated significantly and independently with serum EPA/AA ratio. Serum EPA/AA ratio, but not serum DHA/AA and (EPA+DHA)/AA ratios, was significantly lower in subjects with eVFA ≥100 cm2, compared to those with eVFA <100 cm2 (p=0.049). Subjects with eVFA ≥100 cm2 were significantly more likely to have the metabolic syndrome and history of cardiovascular diseases, compared to those with eVFA <100 cm2 (p<0.001, p=0.028, respectively).
Imbalance of dietary long-chain polyunsaturated fatty acids (low serum EPA/AA ratio) correlated with visceral fat accumulation in male subjects.
Clinical trial registration number
Arachidonic acid; Eicosapentaenoic acid; Docosahexaenoic acid; Visceral fat; Metabolic syndrome; Obesity
Patients on maintenance hemodialysis (HD) have much higher levels of adiponectin (Total-APN). Adiponectin and C1q form a protein complex in human blood, and serum C1q-binding adiponectin (C1q-APN) can be measured. We recently reported that C1q-APN/Total-APN ratio rather than Total-APN correlated with atherosclerosis in diabetics. However, the characteristics of C1q-APN in HD patients remain unclear. The preset study investigated the characteristics of the adiponectin parameters including C1q-APN and also to clarify the relationship between various serum adiponectin parameters and atherosclerotic cardiovascular diseases (ACVD) in HD patients.
The single cross-sectional study subjects were 117 Japanese patients (males/females = 61/56) on regular HD. Blood Total-APN, high molecular weight-adiponectin (HMW-APN), C1q-APN and C1q concentrations were measured by enzyme-linked immunosorbent assays. ACVD were defined as stroke, coronary and peripheral artery diseases, thoracic and abdominal aneurysms.
Stepwise regression analysis identified high-density lipoprotein-cholesterol (HDL-C) as the only significant and independent determinant of C1q-APN in males, and duration of HD as the only significant and independent determinant of C1q-APN in females. Stepwise regression analysis identified uric acid, low-density lipoprotein-cholesterol and triglyceride as significant and independent determinants of C1q-APN/Total-APN ratio in males, and leukocyte count and HDL-C as significant and independent determinants of C1q-APN/Total-APN ratio in females. Multiple logistic regression analysis identified inorganic phosphorus and C1q-APN or C1q-APN/C1q ratio as significant determinants of ACVD.
Low serum C1q-APN and C1q-APN/C1q ratio, but not C1q-APN/Total-APN ratio, correlated with ACVD in HD patients.
Adiponectin; C1q; C1q-binding adiponectin, Hemodialysis
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.
We recently reported that short-term treatment with liraglutide (20.0 ± 6.4 days) reduced body weight and improved some scales of eating behavior in Japanese type 2 diabetes inpatients. However, it remained uncertain whether such liraglutide-induced improvement is maintained after discharge from the hospital. The aim of the present study was to determine the long-term effects of liraglutide on body weight, glycemic control, and eating behavior in Japanese obese type 2 diabetics.
Patients with obesity (body mass index (BMI) >25 kg/m2) and type 2 diabetes were hospitalized at Osaka University Hospital between November 2010 and December 2011. BMI and glycated hemoglobin (HbA1c) were examined on admission, at discharge and at 1, 3, and 6 months after discharge. For the liraglutide group (BMI; 31.3 ± 5.3 kg/m2, n = 29), patients were introduced to liraglutide after correction of hyperglycemic by insulin or oral glucose-lowering drugs and maintained on liraglutide after discharge. Eating behavior was assessed in patients treated with liraglutide using The Guideline For Obesity questionnaire issued by the Japan Society for the Study of Obesity, at admission, discharge, 3 and 6 months after discharge. For the insulin group (BMI; 29.1 ± 3.0 kg/m2, n = 28), each patient was treated with insulin during hospitalization and glycemic control maintained by insulin after discharge.
Liraglutide induced significant and persistent weight loss from admission up to 6 months after discharge, while no change in body weight after discharge was noted in the insulin group. Liraglutide produced significant improvements in all major scores of eating behavior questionnaire items and such effect was maintained at 6 months after discharge. Weight loss correlated significantly with the decrease in scores for recognition of weight and constitution, sense of hunger, and eating style.
Liraglutide produced meaningful long-term weight loss and significantly improved eating behavior in obese Japanese patients with type 2 diabetes.
Liraglutide; Glucagon-like peptide-1 (GLP-1); Obesity; Eating behavior; Diabetes; Incretin
Aims/Introduction: Pronounced reduction of insulin secretion in response to a rise in glucose level has been reported in Japanese patients compared with Caucasian patients, but the mean body mass index (BMI) is also lower in Japanese patients. As BMI is a determinant of insulin secretion, we examined insulin‐secretion capacity in obese and non‐obese Japanese patients.
Materials and Methods: Using the oral glucose tolerance test (OGTT), we estimated the insulin‐secreting capacity in obese (BMI ≥ 25) and non‐obese (BMI < 25) Japanese patients, including 1848 patients with normal glucose tolerance (NGT), 321 patients with impaired glucose tolerance (IGT) and 69 diabetes (DM) patients.
Results: The insulinogenic index (I.I.), calculated by dividing the increment in serum insulin by the increment in plasma glucose from 0 to 30 min during OGTT, decreased from NGT to IGT and to DM in patients with and without obesity. In patients with NGT, IGT and DM, the I.I. values of obese patients were higher than those of the non‐obese patients. The peak of insulin concentration in OGTT appeared at 60 min in NGT and at 120 min in IGT in both obese and non‐obese patients, but in DM it was observed at 120 min in obese patients and at 60 min in non‐obese patients.
Conclusions: These results show that early‐phase insulin secretion in obese Japanese patients is higher than in non‐obese patients in all stages of glucose tolerance, and delayed insulin‐secretion capacity is also conserved in obese Japanese patients, even in IGT and DM, which is similar to Caucasian patients. (J Diabetes Invest, doi:10.1111/j.2040‐1124.2011.00180.x, 2011)
Insulin secretion; Non‐obese Japanese; Obese Japanese
Aims/Introduction: Recently, glucagon‐like peptide‐1 (GLP‐1) receptor agonists of liraglutide have become available in Japan. It has not yet been clarified what clinical parameters could discriminate liraglutide‐effective patients from liraglutide‐ineffective patients.
Materials and Methods: We reviewed 23 consecutive patients with type 2 diabetes admitted to Osaka University Hospital for glycemic control. All of the patients were treated with diet plus insulin (or plus oral antidiabetic drugs) to improve fasting plasma glucose (FPG) and postprandial glucose below 150 and 200 mg/dL, respectively. After insulin secretion and insulin resistance were evaluated, insulin was replaced by liraglutide. The efficacy of liraglutide was determined according to whether glycemic control was maintained at the target levels.
Results: Liraglutide was effective in 13 of 23 patients. There were significant differences in the parameters of insulin secretion, including fasting C‐peptide (F‐CPR), C‐peptide index (CPI), insulinogenic index (I.I.) and urine C‐peptide (U‐CPR), between liraglutide‐effective and ‐ineffective patients. The duration of diabetes was significantly shorter in liraglutide‐effective patients than in liraglutide‐ineffective patients. In receiver operating characteristic analyses, the cut‐off value for predicting the efficacy of liraglutide was 0.14 for I.I., 1.1 for CPI, 1.5 ng/mL for F‐CPR, 33.3 μg/day for U‐CPR and 19.5 years for duration of type 2 diabetes.
Conclusions: Insulin secretion evaluated by F‐CPR, CPI, I.I., U‐CPR and the duration of type 2 diabetes were useful parameters for predicting the efficacy of liraglutide in patients with type 2 diabetes. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2011.00168.x, 2011)
Glucagon‐like peptide‐1; Incretin; Type 2 diabetes
B-type natriuretic peptide (BNP), a member of the natriuretic peptide family, is a cardiac-derived secretory hormone with natriuretic, diuretic, and vasorelaxant activities. Intraabdominal fat accumulation is associated with atherosclerotic cardiovascular diseases and cardiac dysfunction. Circulating BNP levels are relatively low (within the normal limits) in obesity and the metabolic syndrome. However, the relationship between plasma BNP levels and visceral fat accumulation in general population has not been reported. The present study analyzed the relationships between plasma BNP levels and various clinical variables, including insulin, visceral and subcutaneous fat area (VFA and SFA, respectively), in normal Japanese men.
The study (Victor-J study) subjects were consecutive 500 Japanese male workers, who underwent a health checkup and were measured VFA and SFA by computed tomography.
Age-adjusted simple linear regression analysis showed that log-BNP correlated positively with HDL-cholesterol, and negatively with VFA, log-immunoreactive insulin (IRI), log-triglyceride, and LDL-cholesterol, but not body mass index or SFA. Stepwise multiple regression analysis identified log-IRI and HDL-cholesterol as significant determinants of log-BNP. Subjects with IRI ≥5.5 μIU/mL had lower plasma BNP levels than those with IRI < 5.5 μIU/mL, irrespective of obesity (body mass index, cutoff value 25 kg/m2), visceral fat accumulation (VFA, cutoff value 100 cm2) and subcutaneous fat accumulation (SFA, cutoff value 128 cm2).
Our study showed that hyperinsulinemia correlated with low levels of plasma BNP in general men, irrespective of fat distribution.
B-type natriuretic peptide; Hyperinsulinemia; Visceral fat
Sleep-disordered breathing (SDB), especially obstructive sleep apnea (OSA), has frequent complications include hypertension, dyslipidemia and insulin resistance based on abdominal obesity or excess visceral fat (called Syndrome Z). OSA is a potential risk factor for cardiovascular diseases. The clinical characteristics of Japanese OSA subjects with OSA remain unclear. The present study investigated prevalence and predictive factors of intracoronary stenosis detected by multislice computed tomography (MSCT) in Japanese male subjects with SDB/OSA.
The study (O-VFStudy) subjects were 39 Japanese men with SDB/OSA who underwent all-night cardiorespiratory monitoring with fully attended polysomnography, and moreover both fat computed tomography (CT) scan and 64-row MSCT coronary angiography. The prevalence of coronary stenosis in this selected population with SDB/OSA was 15%. Logistic regression analysis showed a significant relationship between age-adjusted CAD and metabolic syndrome (p < 0.05), but not serum adiponectin levels and nocturnal fall in adiponectin. Subjects with the metabolic syndrome had significantly higher prevalence of CAD (31.3 versus 4.3%, p = 0.033), and lower levels of serum adiponectin (4.5 ± 0.6 versus 6.4 ± 0.6 μg/mL, p = 0.014), compared with groups without the metabolic syndrome.
The present study describes that the prevalence of greater than 50% intracoronary stenotic lesions detected by MSCT was 15% and the metabolic syndrome was correlated with intracoronary stenosis detected by MSCT in Japanese SDB/OSA subjects.
Coronary Stenosis; Sleep apnea-hypopnea; Visceral fat; Adiponectin
Ectopic lipid storage in muscle (intramyocellular lipids [IMCL]) and liver (hepatocellular lipids [HCL]) coexists with impaired myocellular flux through ATP synthase (fATPase) in certain cohorts with increased risk of type 2 diabetes. Because women with a history of gestational diabetes mellitus (pGDM) have elevated ectopic lipids and diabetes risk, we tested whether deteriorated energy metabolism contributes to these abnormalities.
RESEARCH DESIGN AND METHODS
A total of 23 glucose-tolerant nonobese pGDM and eight women with normal glucose metabolism during pregnancy with similar age, body mass, and physical activity underwent oral glucose tolerance tests (OGTT) and intravenous glucose tolerance tests at 4–5 years after delivery. OGTT values <463 mL ⋅ min−1 ⋅ m−2 were considered to indicate insulin resistance. pGDM were further stratified into insulin-resistant (pGDM-IR) and insulin-sensitive (pGDM-IS) groups. IMCL, HCL, and fATPase were measured with 1H/31P magnetic resonance spectroscopy.
pGDM had 36% higher fat mass and 12% lower insulin sensitivity. Log-transformed fATPase was lower in pGDM (10.6 ± 3.8 µmol ⋅ mL muscle−1 ⋅ min−1 vs. 12.1 ± 1.4 µmol ⋅ mL muscle−1 ⋅ min−1, P < 0.03) and related to plasma adiponectin after adjustment for body fat (r = 0.44, P < 0.04). IMCL were 61% and 69% higher in pGDM-IR (P < 0.05 vs. pGDM-IS) and insulin resistant women (P < 0.003 vs. insulin sensitive), respectively. HCL were doubled (P < 0.05) in pGDM and insulin resistant women, and correlated positively with body fat mass (r = 0.50, P < 0.01) and inversely with insulin sensitivity (r = −0.46, P < 0.05).
Glucose-tolerant pGDM show increased liver fat but only slightly lower muscular insulin sensitivity and ATP synthesis. This suggests that alteration of hepatic lipid storage represents an early and predominant abnormality in this cohort.
The 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.
The 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).
Our 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.
gastroesophageal reflux symptom; metabolic syndrome; visceral fat; adiponectin