BACKGROUNDAdiponectin is an adipokine with insulin-sensitising and anti-atherogenic properties. The aim of this study was to investigate whether low adiponectin levels predict the impairment of endothelial function in newly diagnosed type 2 diabetic patients in an 8-year prospective study.

METHODSIn the prospective study, we enrolled 133 newly diagnosed type 2 diabetic patients without subclinical atherosclerosis and gave them intensive therapy; the mean treatment period was 8 years. Intensive treatment was a stepwise implementation of behavior modification and pharmacological therapy targeting hyperglycaemia, hypertension, dyslipidaemia and obesity. We measured baseline circulating adiponectin with an enzyme-linked immunosorbent assay, endothelium-dependent and -independent vasodilation by high-resolution vascular ultrasound. At year 8, 102 patients were reexamined for endothelium-dependent and -independent vasodilation.

RESULTSSex-adjusted adiponectin level was positively correlated with endothelium-independent vasodilation both at baseline (r = 0.150, P = 0.043) and at year 8 (r = 0.339, P = 0.001), whereas no association was found between adiponectin and endothelium-dependent vasodilation. In a stepwise multivariate linear regression model, adiponectin was an independent predictor for impaired endothelium-independent vasodilation at year 8 (P = 0.001).

CONCLUSIONSPlasma adiponectin concentration was associated with endothelium-independent vasodilation and hypoadiponectinemia predicted the impairment of endothelium-independent vasodilation in newly diagnosed type 2 diabetic patients under multifactorial intervention. These data support the causative link of impairment of endothelium-independent vasodilation with hypoadiponectinemia.

Adiponectin ; blood ; Diabetes Mellitus, Type 2 ; blood ; physiopathology ; Endothelium, Vascular ; physiology ; Female ; Humans ; Male ; Middle Aged ; Prospective Studies ; Vasodilation ; physiology

It is the intent of this investigation to gain an insight into the relationship of serum total adiponectin with polycystic ovary syndrome (PCOS) and insulin resistance. Fifty-eight PCOS patients were enrolled (29 with high serum insulin level and 29 without), at the same time, 29 non-PCOS women with normal weight were included as control. The influencing factors of total adiponectin, PCOS and insulin resistance were analyzed. The serum total adiponectin of PCOS patients and all participants were found to be negatively related to waist hip ratio (r = -0.39, r = -0.36) and InHOMA-IR (r = -0.53, r = -0.45), respectively. Adiponectin was not a protective factor of PCOS (P > 0.1), but it was that of PCOS-insulin resistance (OR = 0.81; 95% CI: 0.67-0.97; P = 0.02). LH/FSH (OR = 1.51; 95% CI: 1.16-1.96; P = 0.01) and InHOMA-IR (OR = 1.26; 95% CI: 1.10-1.44; P = 0.01) were risk factors of PCOS, and waist hip ratio was that of PCOS-insulin resistance (OR = 8.57; 95% CI, 2.14-34.30, P = 0.01). Adiponectin might influence fasting insulin and InHOMA-IR (B = -0.22, P = 0.001; B = -0.02, P = 0.002). These data signify that adiponectin is not directly related with PCOS, but it is related with PCOS-HL Adiponectin might participate in the pathophysiologic mechanism of PCOS by influencing insulin sensitivity.
Adiponectin ; blood ; Adult ; Female ; Humans ; Insulin Resistance ; physiology ; Polycystic Ovary Syndrome ; blood ; physiopathology ; Waist-Hip Ratio ; Young Adult

OBJECTIVETo investigate the relationship between serum adiponectin and mean blood pressure (BP).

METHODSA total of 187 subjects were divided into four groups according to BP levels: optimal blood pressure group (n = 38), high normal blood pressure group (n = 50), treated hypertension group (n = 54) and untreated hypertension group (n = 45). Serum adiponectin and microalbuminuria were detected by radioimmunology assay. Insulin resistant index defined as HOMA-IR and urinary concentration of microalbuminuria/urinary concentration of creatinine defined as albumin creatinine ratio (ACR) were calculated.

RESULTS(1) Serum adiponectin decreased in proportion to BP increase and the serum adiponectin level was significantly higher in treated hypertension group than untreated hypertension group. (2) Correlation analysis showed that adiponectin concentration was negatively correlated with mean blood pressure (P < 0.01). (3) Multivariate regression analysis revealed that mean blood pressure and HOMA-IR were independent predictors of serum adiponectin level.

CONCLUSIONSMean blood pressure was the main determinant of serum adiponectin level and negatively correlated to serum adiponectin level.

Adiponectin ; blood ; Adult ; Blood Pressure ; physiology ; Female ; Humans ; Insulin Resistance ; Male ; Middle Aged ; Physical Examination ; statistics & numerical data

OBJECTIVETo investigate the relationship between adiponectin and beta-cell function in abdominal visceral obesity women.

METHODSNine abdominal visceral obesity women (VO), 9 normal subjects (C) and 7 patients with type 2 diabetes mellitus (T2DM) were enrolled in the study. Beta-cell function and insulin sensitivity were determined by hyperglycemic clamp, fasting serum adiponectin was assayed by ELISA and regional body fat was measured by MRI.

RESULTThe levels of first phase insulin release (FPIR), glucose disposal rates (GDR), insulin sensitivity index (ISI) and adiponectin were significantly elevated in control group compared with VO group and T2DM group. As compared with T2DM group, the levels of adiponectin, FPIR, second phase insulin release (SPIR) and maximum insulin release (INS(max)) increased significantly in VO group. Multiple stepwise regression analysis showed that age, FPIR and GDR were positively correlated to adiponectin (B=0.145, 0.194, 0.277 respectively, all P<0.05), while waist-hip ratio was negatively correlated with adiponectin (B=-7.424, P<0.05).

CONCLUSIONThe visceral obesity women have lower adiponectin levels, and hyperadiponectinemia may be the link with insulin secretion.

Abdominal Fat ; Adiponectin ; blood ; Adult ; Female ; Glucose Clamp Technique ; Humans ; Insulin-Secreting Cells ; physiology ; Middle Aged ; Obesity ; blood ; physiopathology

OBJECTIVE: To examine the serum visfatin, adiponectin and leptin levels in patients with polycystic ovarian syndrome (PCOS), and to explore the basis of the pathogenesis of PCOS. METHODS: A PCOS group (n=73) and a healthy control group (n=75) were included in the study, which were matched in age and body mass index (BMI). Serum visfatin, adiponectin, leptin, sex hormone levels, and metabolic parameters were measured by enzyme-linked immunosorbent assay (ELISA) or radioimmunoassay (RIA). RESULTS Serum levels of fasting insulin(Fins), homeostatic model assessment for insulin resistance (HOMA-IR), testosterone (T), luteinizing hormone (LH), and prolactin (PRL) in the PCOS group were significantly higher than those in the healthy group(all P<0.05),and follicle-stimulating hormone (FSH) level was significantly decreased in the PCOS group. The visfatin and leptin levels in the PCOS group increased significantly than those in the healthy group [PCOS group: (95.30+/-31.90) and (11.10+/-3.87) microg/L; healthy group: (73.20+/-20.30) and (7.21+/-2.47) microg/L,P<0.001]. The adiponectin level was significantly lower than that in the healthy group [PCOS group: (4.21+/-1.17) mg/L; healthy group:( 6.39+/-1.53) mg/L,P<0.001]. Pearson correlation analysis showed that visfatin level was negatively related to adiponectin levels (r=-0.452 and -0.378, P<0.01), but positively related to leptin and HOMA-IR levels in both the PCOS group and the healthy group (r=0.379-0.556, all P<0.01). The correlation remained between the visfatin and HOMA-IR levels in the PCOS group after correcting the influence of BMI. CONCLUSION Patients with PCOS have high visfatin and leptin levels but low adiponectin levels. Visfatin levels are positively related to insulin resistance.
Adiponectin ; blood ; Adolescent ; Adult ; Case-Control Studies ; Female ; Humans ; Insulin Resistance ; physiology ; Leptin ; blood ; Nicotinamide Phosphoribosyltransferase ; blood ; Polycystic Ovary Syndrome ; blood ; Young Adult

BACKGROUNDGenioglossal dysfuntion takes an important role in pathogenesis of obstructive sleep apnea hypopnea syndrome (OSAHS) in which chronic intermittent hypoxia (CIH) is the major pathological origin. Recent studies have suggested genioglossal injury induced by CIH might be improved by adiponectin. The aim of this study was to investigate the effects of adiponectin on genioglossus contractile properties in rats exposed to CIH.

METHODSThirty-nine healthy male Wistar rats were randomly divided into three groups: normal control (NC), CIH and adiponectin supplement (CIH+Ad) with 13 rats in each. Rats in NC were kept breathing normal air, while rats in CIH and CIH+Ad experienced the same CIH environment eight hours per day for 35 successive days. Rats in CIH+Ad were given intravenous adiponectin of 10 µg twice a week for 30 successive days. Rats in the NC and CIH were injected with normal saline as a control. After 35 days' CIH exposure, the levels of serum adiponectin and genioglossus contractile properties were compared.

RESULTSSerum adiponectin level was significantly lower in CIH than in NC (1210 ng/ml vs. 2236 ng/ml). Serum adiponectin level in CIH+Ad (1844 ng/ml) was significantly higher than CIH but lower than NC. Twitch tension, time to peak tension, half relaxation time and tetanic tension were significantly lower in CIH than NC and improved in CIH+Ad. All mean tetanic fatigue indices decreased more rapidly in the first 20 seconds than during the subsequent 100 seconds. Tetanic fatigue indices in NC and CIH+Ad were significantly higher compared to CIH.

CONCLUSIONSCIH could lead to hypoadiponectinaemia, impaired genioglossus contractile properties and decreased fatigue resistance in rats. Such changes could be partially offset by supplementation of adiponectin.

Adiponectin ; blood ; therapeutic use ; Animals ; Hypoxia ; blood ; physiopathology ; Male ; Muscle Contraction ; physiology ; Rats ; Rats, Wistar ; Sleep Apnea, Obstructive ; blood ; drug therapy ; physiopathology

OBJECTIVE: To determine whether serum adipocytokines and leptin level are associated with bone mineral density (BMD) in postmenopausal women. METHODS: Serum adiponectin and leptin level were measured by ELISA in 336 postmenopausal women. BMD was measured by dual energy X-ray absorptiometry (DXA) at the whole body, lumbar spine, hip, and forearm. Body compositions including lean tissue mass and body fat mass were measured by DXA, and their relationship was analyzed. RESULTS: Serum adiponectin levels were negatively related to BMD at the whole body, the lumbar spine, the hip, and the forearm (r = -0.181, r = -0.208, r = -0.228, r = -0.203, and P < 0.05, respectively). After adjustment for age and fat mass, the correlation with BMD still remained (r = -0.131, r = -0.140, r = -0.159, r = -0.172, and P<0.05, respectively). Serum leptin levels were positively related to BMD was at the hip and the forearm (r = 0.162, r = 0.210, and P < 0.05, respectively). After adjustment for age and fat mass, the correlation with BMD at the forearm remained (r = 0.157, P<0.05), but the correlation with BMD at the hip disappeared. In the multiple linear stepwise regression analysis, year since menopause, lean mass, adiponectin, and estradiol were independent predictors of BMD at the body, the hip and the forearm; year since menopause, lean mass, body mass index, adiponectin, and extradiol were independent predictors of BMD at the lumbar spine. CONCLUSION Adiponectin is the independent predictor of BMD.
Absorptiometry, Photon ; Adiponectin ; blood ; Aged ; Aged, 80 and over ; Bone Density ; physiology ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Leptin ; blood ; Middle Aged ; Postmenopause ; blood ; metabolism

OBJECTIVE: To examine the plasma adiponectin concentration in coronary heart disease (CHD) patients combined with abnormal glucose metabolism, and to explore the clinical significance of adiponectin. METHODS: Eighty-seven hospitalized CHD patients confirmed by coronary angiography from August 2009 to April 2010 at Xiangya Hospital were enrolled and divided into 3 groups according to their glucose metabolic state: 31 patients were selected as a simple CHD group, 28 were selected as a CHD combined with impaired glucose tolerance group (CHD+IGT group), and the other 28 as a CHD combined with diabetes mellitus group (CHD+DM group). The 31 healthy subjects who got health checkup at the same time were enrolled as a normal control group (NC group). Plasma adiponectin was measured by enzyme linked immunosorbent assay. The height, weight,waistline and blood pressure of all the subjects were checked, and the fasting blood glucose (FBG), insulin, lipids, high-sensitivity C-reactive protein (hs-CRP), free fatty acids (FFA), the liver function and the renal function were checked as well. The body mass index and the homeostasis model were assessed for insulin resistance. RESULTS: 1) Plasma adiponectin in the CHD group, the CHD+IGT group, and the CHD+DM group was all lower than that in the NC group (P<0.05); 2) Compared with the CHD group, the plasma adiponectin in the CHD+DM group was the lowest, followed by the CHD+IGT group, and there was significant difference in the 3 groups (P<0.05); 3) Plasma adiponectin level was positively related with the high density lipoprotein cholesterol-C (HDL-C) (r=0.483, P<0.01), while it was negatively related with the hs-CRP and Gensini score (r=-0.489, P<0.05;r=-0.252, P<0.05). CONCLUSION Plasma adiponectin concentration is reduced in the CHD patients, and significantly reduced in CHD patients combined with abnormal glucose metabolism. Plasma adiponectin concentration decreases significantly with the severity of abnormal glucose metabolism. CHD and the abnormal glucose metabolism are important influence factors for plasma adiponectin. That plasma adiponectin level significantly decreases may be the superimposed results of CHD and abnormal glucose metabolism. Plasma adiponectin combined with HDL-C, hs-CRP and Gensini score may provide the reference in the judgement of the severity of CHD patients with abnormal glucose metabolism.
Adiponectin ; blood ; Aged ; Coronary Disease ; blood ; complications ; metabolism ; Diabetes Mellitus, Type 2 ; blood ; complications ; Female ; Humans ; Insulin Resistance ; physiology ; Male ; Middle Aged

BACKGROUNDHyperinsulinemic euglycemic clamp is the gold standard to evaluate the insulin sensitivity, but it is too complicated and expensive to use in clinic. We tried to find an alternative indicator to reflect insulin sensitivity. To evaluate the association between the four adipokines, adiponectin, leptin, resistin and tumor necrosis factor-alpha (TNF-alpha) with insulin sensitivity, we used a hyperinsulinemic euglycemic clamp to test insulin sensitivity in Chinese patients with obesity and type 1 or type 2 diabetes mellitus versus controls.

METHODSIn this parallel control study, we tested insulin sensitivity using a hyperinsulinemic euglycemic clamp in different groups, then examined levels of adiponectin, leptin, resistin and TNF-alpha in serum, and the relationship between the different adipokines and glucose disposal rate (M value), as well as insulin sensitivity index (M value/insulin, M/I), which are the "gold standard" indices of insulin sensitivity.

RESULTSThere were significant differences in mean leptin values in the four adipokines from the four different groups (P < 0.001; comparison of the variation between different groups was analyzed by variance analysis). Compared to controls (using multiple comparison two-way Dunnett t test), only the leptin level showed significant differences in the four adipokines from the four different groups at the same time (P < 0.001). The association analysis between the different adipokines and M or M/I values also showed that only leptin negatively correlated with M (r = -0.64, P < 0.001) or M/I values (r = -0.56, P < 0.001); there was no relationship between the other three adipokines and M or M/I values.

CONCLUSIONOnly leptin was associated with M or M/I values. Therefore, leptin might be one of the predictive factors of the degree of insulin resistance and risk of the accompanying disease.

Adipokines ; blood ; Adiponectin ; blood ; Asian Continental Ancestry Group ; Diabetes Mellitus, Type 1 ; blood ; Diabetes Mellitus, Type 2 ; blood ; Glucose Clamp Technique ; Humans ; Insulin Resistance ; physiology ; Leptin ; blood ; Obesity ; blood ; Resistin ; blood ; Tumor Necrosis Factor-alpha ; blood

BACKGROUNDThe genioglossus (GG) is involved in the maintenance of an open airway for effective breathing. Although the pathogenesis of obstructive sleep apnea hypopnea syndrome (OSAHS) was closely associated with GG dysfunction, its causes and possible treatment have not been elucidated. The aim of the study was to investigate the effects of chronic intermittent hypoxia (CIH) on serum adiponectin levels, electromyograph (EMG) activity and ultrastructure of GG, as well as the effect of an adiponectin supplement in anesthetized rats.

METHODSForty-two healthy male Wistar rats were randomly divided into normal control (A), CIH (B) and adiponectin treatment (C) groups, 14 rats in each group. CIH was performed eight hours per day for five weeks in both groups B and C. Group C received transvenous injection of adiponectin at the dosage of 10 microg per injection, twice a week for five weeks. At the end of the 5th week the GG EMG voltage was measured and compared among the three groups. Transmission electron microscope was used to observe the ultrastructure of the GG.

RESULTSCIH caused significant hypoadiponectinemia, weakened activity of GG EMG at both baseline and hypoxia stimulation, and induced ultrastructural pathological changes, such as, myofibril discontinuities, lysis of myofilament, edema of mitochondria and disruption of cristae, vacuolus and lysis of some mitochondria. Venous supplement of adiponectin improved the above pathological changes resulting from CIH.

CONCLUSIONCIH resulted in pathological changes in GG's EMG and ultrastructure, which could be improved by supplement of adiponectin and be associated with hypoadiponectinemia caused by CIH.

Adiponectin ; administration & dosage ; blood ; Animals ; Electromyography ; Hypoxia ; blood ; physiopathology ; Male ; Microscopy, Electron, Transmission ; Muscle, Skeletal ; physiology ; ultrastructure ; Random Allocation ; Rats ; Rats, Wistar ; Sleep Apnea, Obstructive ; blood ; physiopathology ; Tongue ; physiology ; ultrastructure