Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Adiponectin”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 343 records · Page 19Linked to original sources

Aberrant serum adiponectin levels in women with uterine leiomyomas.

BACKGROUND: Adiponectin is an adipocyte-secreted hormone. Serum adiponectin levels are inversely correlated with insulin resistance, and low plasma adiponectin levels have been demonstrated in type 2 diabetic patients. However, information on serum adiponectin levels in gynecological disorders is mostly lacking. In this study, we analyzed the possible correlation between serum adiponectin levels and uterine leiomyomas. METHODS: Serum adiponectin levels, determined by radioimmunoassay, were compared in women with uterine leiomyomas (n = 47) and normal controls (n = 46). RESULTS: Serum adiponectin levels in women with uterine leiomyomas (16.4 +/- 0.9 microg/ml) were significantly lower (p < 0.05) than those in the normal controls (19.5 +/- 1.0 microg/ml). Furthermore, there was an inverse correlation between serum adiponectin levels and body mass index, in both women with leiomyomas and normal controls. CONCLUSIONS: Serum adiponectin levels are significantly decreased in myomatous patients.

Adiponectin↗

Markers of endothelial cell activation/injury: CD146 and thrombomodulin are related to adiponectin in kidney allograft recipients.

BACKGROUND: Adiponectin may be used for assessing the risk of coronary artery disease (CAD) and may be related to the development of acute coronary syndrome. Decreased adiponectin has been associated with some risk factors for cardiovascular diseases such as male sex, obesity and diabetes mellitus. Adiponectin has antiatherogenic properties and attenuates endothelial inflammatory responses. CD146, a novel cell adhesion molecule, is localized at the endothelial junction. In kidney allograft recipients, endothelial dysfunction and atherosclerosis are almost universal. The aim of this cross-sectional study was to evaluate possible relations between adiponectin, CD146, and other markers of endothelial cell injury in 82 stable kidney transplant recipients (mean age 45 years, mean time after transplantation 47 months) with and without CAD. METHODS: Adiponectin and markers of endothelial injury: CD146, von Willebrand factor, thrombomodulin, ICAM, CD40L, P-selectin and other hemostatic markers were assessed using commercially available kits. RESULTS: Patients with CAD had evidence of more pronounced endothelial dysfunction, procoagulant state and lower adiponectin than patients without CAD. Adiponectin correlated significantly, in univariate analysis, with CD146 (r = 0.29, p = 0.009), thrombomodulin (r = 0.37, p = 0.001), protein Z (r = -0.25, p = 0.03), BMI (r = -0.26, p = 0.047), serum creatinine (r = 0.26, p = 0.02) and urea (r = 0.38, p = 0.001). CD146 correlated significantly with von Willebrand factor (r = 0.33, p = 0.002), thrombomodulin (r = 0.25, p = 0.025), age (r = 0.34, p = 0.001), platelets (r = -0.33, p = 0.002), serum urea (r = 0.24, p = 0.039), cholesterol (r = 0.24, p = 0.046), ICAM (r = 0.23, p = 0.036), protein C activity (r = -0.26, p = 0.019) and tended to correlate with serum creatinine and time after transplantation. In multivariate linear regression, independent predictors of adiponectin were CD146, thrombomodulin and urea, and of CD146 was mainly age of patients. CONCLUSIONS: Endothelial dysfunction and procoagulant state are more pronounced in kidney transplant recipients with CAD, particularly in those with lower GFR. In kidney transplant recipients, markers of endothelial cell injury are significantly increased relative to healthy volunteers. Elevation of adiponectin may be a defense mechanism against endothelial damage, reflected by elevated CD146 and thrombomodulin.

Adiponectin↗

Higher basal adiponectin levels are associated with better ovarian response to gonadotropin stimulation during in vitro fertilization.

AIMS: To measure adiponectin levels in the serum samples from day 3 of the menstrual cycle prior to the administration of gonadotropin during in vitro fertilization, and to measure any correlations between adiponectin levels and the number of oocytes retrieved, body weights and body mass indexes. Also, to examine whether there is a difference in adiponectin levels between women who conceive and those who do not. METHODS: In a case-control design, 56 women undergoing in vitro fertilization procedures were included in this study: 28 women who conceived were matched with 28 women who did not conceive. Adiponectin levels in serum were determined by radioimmunoassay and compared. RESULTS: The adiponectin levels were positively correlated with the number of oocytes retrieved (r = 0.306, p = 0.022), but negatively correlated with body mass index and body weight (r = -0.367, p = 0.005; r = -0.326, p = 0.014). No significant correlations were found between the number of oocytes retrieved and body mass index or body weight (r = 0.020, p = 0.882; r = 0.069, p = 0.613). We further observed that adiponectin levels in women who conceived (23.0 +/- 2.0 microg/ml) were found to be significantly higher (p = 0.026) than those in women who did not conceive (17.3 +/-1.4 microg/ml). The number of oocytes retrieved from women who conceived (13.3 +/- 0.9) was also higher than that in women who did not (10 +/- 1.2; p = 0.029). CONCLUSIONS: The number of oocytes retrieved was found to correlate positively with the adiponectin levels on the day prior to the administration of gonadotropin. In addition, basal adiponectin levels were significantly higher in those women who conceived. Therefore, adiponectin is a better marker of adequate follicular development during in vitro fertilization than is body weight or body mass index.

Adiponectin↗

Increased serum high-molecular-weight complex of adiponectin in type 2 diabetic patients with impaired renal function.

BACKGROUND/AIM: Adiponectin, an adipocyte-derived protein, has been shown to exert antidiabetic, anti-inflammatory, and antiatherosclerotic effects. Although recent reports show an increase in the total adiponectin levels in chronic kidney disease patients and in patients with end-stage renal disease, the nature of biodegradation and renal involvement of adiponectin is largely unknown. We aimed at determining whether the high-molecular-weight (HMW) complex of adiponectin is associated with renal insufficiency in type 2 diabetic patients. METHODS: A total of 179 type 2 diabetic patients were selected from among outpatients and divided into four groups according to their albumin-to-creatinine ratio: patients with normoalbuminuria (n = 86), patients with microalbuminuria (n = 44), patients with macroalbuminuria (n = 23), and patients on hemodialysis (n = 26). The serum HMW adiponectin was specifically assayed with a commercially available enzyme-linked immunosorbent assay kit. RESULTS: The HMW adiponectin levels were higher in patients on hemodialysis (17.1 +/- 8.2 microg/ml) and in those with macroalbuminuria (14.3 +/- 8.7 microg/ml) than in patients with normoalbuminuria (7.2 +/- 5.6 microg/ml) and microalbuminuria (10.8 +/- 7.0 microg/ml). Univariate linear regression analysis showed that the HMW adiponectin concentrations correlated negatively with the estimated glomerular filtration rate in patients with normoalbuminuria, microalbuminuria, and macroalbuminuria (r = -0.42, p < 0.001). Multiple stepwise regression analysis disclosed that estimated glomerular filtration rate, pioglitazone therapy, gender differences, and systolic blood pressure were independently associated with HMW adiponectin levels (r = 0.56). CONCLUSIONS: The serum HMW adiponectin concentrations are higher in type 2 diabetic patients with nephropathy, and these levels are also associated with renal insufficiency.

Adiponectin↗

Adiponectin is inversely related to plasminogen activator inhibitor type 1 in patients with stable exertional angina.

Adipose tissue is a secretory organ producing a variety of bioactive substances, such as adiponectin. Adiponectin has antiatherogenic properties while plasminogen activator inhibitor type 1 (PAI-1) is closely involved in the development of atherosclerosis. The relationship between adiponectin and PAI-1 in patients with coronary artery disease (CAD) has not been clarified. This study examined plasma levels of adiponectin and PAI-1 in 64 patients with stable exertional angina (SEA) and 65 patients with the chest pain syndrome (CPS). Plasma log-adiponectin levels were significantly lower in patients with SEA (0.62+/-0.08 micro g/dL) compared to those with CPS (0.86+/-0.05 micro g/dL) (p<0.0001). The plasma levels of log-PAI-1 were significantly higher in patients with SEA (1.23+/-0.18 ng/mL) compared to those with CPS (1.15+/-0.22 ng/mL) (p<0.05). Plasma log-adiponectin levels correlated negatively with diabetes mellitus (DM), body mass index (BMI), log-PAI-1 (r=-0.284, p<0.001), triglyceride (TG), and remnant-like particles cholesterol (RLP-C), and positively with high-density lipoprotein cholesterol (HDL-C) levels. Plasma levels of log-PAI-1 correlated positively with DM, BMI,TG and RLP-C levels, and negatively with HDL-C levels. Multiple logistic regression analysis identified sex, angina pectoris, and PAI-1 as independent determinants of hyperadiponectinemia (p<0.05). Adiponectin is inversely related to PAI-1. DM, BMI,TG, HDL-C, and RLP-C are common mediators between adiponectin and PAI-1, and treatment for common mediators may prevent the development of CAD by reducing PAI-1 and increasing adiponectin levels.

Adiponectin↗

Paradoxical elevation in adiponectin concentrations in women with preeclampsia.

Adiponectin is a recently identified, insulin-sensitizing and anti-inflammatory protein released by adipocytes, which is paradoxically reduced in obesity. It suppresses endothelial activation. Physiological insulin resistance occurs in normal pregnancy and is exaggerated in women with preeclampsia (PE), together with enhanced inflammatory and endothelial activation. Women with increased body mass index (BMI) and insulin resistance are predisposed to PE. We hypothesized that adiponectin concentrations are reduced in normal pregnancy compared with postpartum values and further reduced in women with PE. Fifteen women with PE and 30 control subjects with similar first trimester BMI had adiponectin concentrations measured in the third trimester; postpartum measurements were repeated in 16 control subjects. Adiponectin concentration in healthy pregnant women correlated inversely with early pregnancy BMI (r=-0.47, P=0.01) and fasting insulin concentrations (r=-0.58, P=0.001). However, adiponectin concentrations did not differ significantly in pregnancy and postpartum samples (mean change, -0.15 microg/mL; 95% CI, -2.28 to 1.98, P=0.88). Plasma adiponectin concentrations were markedly elevated (P=0.01) in women with PE (mean, 21.6; SD, 8.18 microg/mL) compared with control subjects (mean, 14.7; SD, 7.06 microg/mL). Moreover, in PE, adiponectin concentrations did not correlate with first trimester BMI or insulin or with serum urate or creatinine concentrations or urinary protein levels. We conclude that plasma adiponectin concentrations are not elevated in normal human pregnancy and paradoxically elevated (by 47%) in women with PE. This may be secondary to exaggerated nonspecific adipocyte lipolysis or as a physiological response to enhance fat utilization and attenuate endothelial damage. Future studies should determine whether adiponectin concentrations help improve prediction of PE.

Adiponectin↗

Selective suppression of endothelial cell apoptosis by the high molecular weight form of adiponectin.

Adiponectin is an adipocyte-derived, antiatherogenic protein that is present in serum as three isoforms. Total adiponectin levels are decreased in obese or diabetic humans or animal models. This study was designed to elucidate the relative isoform distribution of adiponectin in human disease states and identify the active form of adiponectin toward vascular endothelial cells. The percentage of high molecular weight form (HMW) per total adiponectin was significantly lower in patients with coronary artery disease than control subjects, whereas the hexamer form was similar and the trimer form was significantly higher. During weight reduction in obese subjects, the HMW form increased and the trimer and hexamer forms decreased. Recombinant adiponectin dose-dependently suppressed apoptosis and caspase-3 activity in human umbilical vein endothelial cells (HUVECs). Transduction with dominant-negative AMP-activated protein kinase (AMPK) abolished the suppressive effect of adiponectin on HUVECs. Gel filtration chromatography was used to separate the adiponectin isoforms, and the antiapoptotic effect toward HUVECs was only observed with the HMW form. These data suggest that HMW adiponectin specifically confers the vascular-protective activities of this adipocytokine. The full text of this article is available online at http://circres.ahajournals.org.

AMP-Activated Protein Kinases↗

Plasma adiponectin levels and sonographic phenotypes of subclinical carotid artery atherosclerosis: data from the SAPHIR Study.

BACKGROUND AND PURPOSE: Adipose tissue produces and secretes a number of bioactive molecules, conceptualized as adipocytokines. Adiponectin has been identified as one of the adipocytokines, and hypoadiponectinemia was demonstrated in patients with obesity, diabetes mellitus, and coronary artery disease. Whether decreased adiponectin levels are cause or consequence is an important issue in the discussion on the association between adiponectin and atherosclerosis. In the present study, we investigated the association of plasma adiponectin levels with sonographic phenotypes of subclinical atherosclerosis, which may represent different stages of disease as well as common and distinct determinants. METHODS: A total of 1515 middle-aged healthy white subjects (940 males and 575 females) were included. Common carotid artery intima-media thickness (CIMT) and presence of atherosclerotic plaques were assessed by B-mode ultrasound. RESULTS: After adjustment for established risk factors, per 1 microg/mL decrease in adiponectin CIMT increased on the average by 3.48 microm in males (95% CI, 1.23 to 5.73 microm) and by 2.39 microm in females (95% CI, 0.50 to 4.27 microm). After dichotomizing adiponectin levels at the median and adjustment for established risk factors, the mean difference of CIMT between subjects with low and high adiponectin levels was 20.42 microm in men (95% CI, 6.80 to 34.04; P=0.003) and 20.75 microm in women (95% CI, 1.08 to 40.42; P=0.039). No significant relationship was found between adiponectin levels and presence of atherosclerotic plaques. CONCLUSIONS: Our results demonstrate an independent negative association of adiponectin levels and CIMT, whereas no relationship with presence of atherosclerotic plaques was found, thus suggesting hypoadiponectinemia as a risk factor in the development of early atherosclerosis.

Adiponectin↗

Plasma adiponectin, body mass index, and mortality in patients with chronic heart failure.

BACKGROUND: Recent studies have suggested that higher body mass index (BMI) is associated with improved prognosis in chronic heart failure (CHF). The adipocytokine adiponectin is inversely associated with BMI, and in healthy subjects, low adiponectin is a predictor of mortality. In a prospective study, we therefore evaluated the association between plasma adiponectin levels and mortality among patients with CHF. METHODS AND RESULTS: In 195 CHF patients (age 69.3+/-10.2 years, BMI 27.3+/-5.2 kg/m2, left ventricular ejection fraction 30+/-8.9%, mean+/-SD), plasma adiponectin and N-terminal pro brain natriuretic peptide (NT-proBNP) were measured at baseline. Adiponectin was positively associated with NT-proBNP (beta=0.47, P<0.001), and both biomarkers were negatively associated with BMI (beta=-0.43, P<0.001 for adiponectin and beta=-0.38, P<0.001 for NT-proBNP, respectively) During a median follow-up of 2.6 years, 46 (23.5%) of the patients died. After adjustment for clinical variables associated with CHF severity (age, systolic blood pressure, left ventricular ejection fraction <25%, duration of CHF, and creatinine clearance) and for NT-proBNP, the hazard ratio of mortality for values in the 2 upper tertiles relative to the lowest tertile of adiponectin was 3.23 (P=0.032). BMI predicted mortality independently of clinical parameters of CHF severity (hazard ratio=0.63, P=0.012), but this association became insignificant after additional adjustment for NT-proBNP (hazard ratio=0.74, P=0.13). CONCLUSIONS: A high adiponectin level was a predictor of mortality, independent of risk markers of CHF severity, presumably because of its role as a marker for wasting. BMI was also associated with mortality, but a part of this relation may be mediated by adiponectin and NT-proBNP levels.

Adiponectin↗

The fat-derived hormone adiponectin alleviates alcoholic and nonalcoholic fatty liver diseases in mice.

Adiponectin has recently been shown to be a promising candidate for the treatment of obesity-associated metabolic syndromes. Replenishment of recombinant adiponectin in mice can decrease hyperglycemia, reverse insulin resistance, and cause sustained weight loss without affecting food intake. Here we report its potential roles in alcoholic and nonalcoholic fatty liver diseases in mice. Circulating concentrations of adiponectin decreased significantly following chronic consumption of high-fat ethanol-containing food. Delivery of recombinant adiponectin into these mice dramatically alleviated hepatomegaly and steatosis (fatty liver) and also significantly attenuated inflammation and the elevated levels of serum alanine aminotransferase. These therapeutic effects resulted partly from the ability of adiponectin to increase carnitine palmitoyltransferase I activity and enhance hepatic fatty acid oxidation, while it decreased the activities of two key enzymes involved in fatty acid synthesis, including acetyl-CoA carboxylase and fatty acid synthase. Furthermore, adiponectin treatment could suppress the hepatic production of TNF-alpha and plasma concentrations of this proinflammatory cytokine. Adiponectin was also effective in ameliorating hepatomegaly, steatosis, and alanine aminotransferase abnormality associated with nonalcoholic obese, ob/ob mice. These results demonstrate a novel mechanism of adiponectin action and suggest a potential clinical application of adiponectin and its agonists in the treatment of liver diseases.

Adiponectin↗

Leptin and adiponectin stimulate the release of proinflammatory cytokines and prostaglandins from human placenta and maternal adipose tissue via nuclear factor-kappaB, peroxisomal proliferator-activated receptor-gamma and extracellularly regulated kinase 1/2.

Beyond their effects on central metabolic functions, leptin, resistin, and adiponectin have profound effects on a number of other physiologic processes, including immune function and inflammation. Although leptin, resistin, and adiponectin are produced in human placenta and adipose tissue, their immunoregulatory actions in these tissues are not known. Therefore, the aim of this study was to determine the effect of leptin, resistin, and adiponectin on the release of proinflammatory mediators in human placenta and sc adipose tissue. Samples were obtained from normal pregnancies at the time of cesarean section. Tissue explants (n = 5) were incubated in the absence (basal control) or presence of a leptin (1, 10, and 100 ng/ml), resistin (1, 10, and 100 ng/ml), and adiponectin (0.1 and 0.5 microg/ml). After 6 h incubation, the medium was collected, and the release of IL-1beta, IL-6, TNFalpha, prostaglandin (PG)F2alpha and PGE2 was quantified by ELISA. There was no effect of resistin on proinflammatory cytokine or prostaglandin release; however, leptin at 100 ng/ml and adiponectin at 0.1 and/or 0.5 microg/ml significantly increased the release of IL-1beta, IL-6, TNFalpha, and PGE2 from human placenta and adipose tissue. Although both leptin and adiponectin significantly increased PGF2alpha release from human placenta, there was no effect of these hormones on PGF2alpha release from adipose tissue. Furthermore, this leptin- and adiponectin-induced proinflammatory response could be abrogated by treatment with the antiinflammatory ERK1/2 MAPK inhibitor U0126, the peroxisomal proliferator-activated receptor-gamma ligand troglitazone, and the nuclear factor-kappaB inhibitor BAY 11-7082. Collectively, these data indicate that leptin and adiponectin activate proinflammatory cytokine release and phospholipid metabolism in human placenta and adipose tissue, and antiinflammatory agents can abrogate leptin- and adiponectin-induced inflammation.

Adiponectin↗

Plasma adiponectin concentrations in relation to endometrial cancer: a case-control study in Greece.

Adiponectin is a hormone secreted exclusively by adipocytes, and obesity is an established risk factor for endometrial cancer. We have, thus, evaluated the association of adiponectin with the occurrence of endometrial cancer. Questionnaire information and blood samples were taken before treatment from 84 women with newly diagnosed, histologically confirmed endometrial cancer and 84 control women who were admitted for minor gynecologic problems, mainly pelvic prolapse. Adiponectin levels were measured by immunoassay. The results were analyzed through multiple logistic regression and controlled for known risk factors for endometrial cancer, leptin, as well as major components of the IGF system (IGF-I, IGF-II, and IGF-binding protein 3). Among control women, there was no significant association of adiponectin with age or parity. Although there was no association of adiponectin with endometrial cancer among women 65 yr or older, there was an inverse, fairly strong, and statistically significant inverse association among younger women. Among women younger than 65 yr, an increase of adiponectin by 1 SD was associated with a more than 50% reduction of the risk for endometrial cancer [odds ratio (OR) 0.44; 95% confidence interval (CI) 0.24-0.81], even after controlling for body mass index and other potential confounders. Among all women, the adjusted OR for a 1 SD increase in adiponectin was not significant (OR, 0.78; 95% CI, 0.56-1.10) but was significant for a one quintile increase in adiponectin (OR, 0.74; 95% CI, 0.56-0.97). In women younger than 65 yr, among whom obesity represents a powerful risk factor for endometrial cancer, adiponectin is inversely and significantly related to the risk of this disease. This association is independent of possible effects of major components of the IGF system, leptin, body mass index, sociodemographic variables, and known endometrial cancer risk factors. Future studies are needed to prove causality and provide insight on both the mechanism of action of this hormone and its potential role in endometrial cancer.

Adiponectin↗

Low adiponectin levels in adolescent obesity: a marker of increased intramyocellular lipid accumulation.

We examined the impact of adolescent obesity on circulating adiponectin levels and the relationship between adiponectin and insulin sensitivity, intramyocellular (IMCL) lipid content, plasma triglycerides, and free fatty acids. Plasma adiponectin levels were measured in 8 nonobese (percentage fat, 18 +/- 1.8) and 14 obese adolescents (percentage fat, 41 +/- 1.6). Insulin sensitivity was assessed by the euglycemic-hyperinsulinemic clamp. Intramuscular lipid content was quantified using (1)H-nuclear magnetic resonance spectroscopy, and abdominal fat distribution by magnetic resonance imaging. Adiponectin levels were lower in obese adolescents (9.2 +/- 1 microg/ml, P < 0.001) and were positively related to insulin sensitivity in all subjects (r = 0.531, P < 0.02). Strong inverse relationships were found between adiponectin and triglyceride levels (r = -0.80, P < 0.001) and IMCL (r = -0.73, P < 0.001). Triglycerides (partial r(2) = 0.52; P < 0.0002) and IMCL (partial r(2) = 0.10; P < 0.05) were the most significant predictors of adiponectin levels, explaining 62% of the variation. In conclusion, plasma adiponectin levels are reduced in adolescent obesity and related to insulin resistance, independent of total body fat and central adiposity. There is a strong relationship between adiponectin and IMCL lipid content in this pediatric population. The putative modulatory effects of adiponectin on insulin sensitivity may, in part, be mediated via its effects on IMCL lipid content.

Abdomen↗

Diurnal and ultradian dynamics of serum adiponectin in healthy men: comparison with leptin, circulating soluble leptin receptor, and cortisol patterns.

Adiponectin is an abundant serum adipokine secreted exclusively from differentiated adipocytes, which plays an important role in regulating insulin sensitivity. The dynamics of circulating adiponectin concentrations have yet to be systematically investigated. We sought to determine whether serum adiponectin levels exhibit diurnal or ultradian rhythms in healthy normal-weight men and to compare the 24-h profile of adiponectin fluctuations with those of leptin, leptin-binding protein (sOB-R), and cortisol. We collected blood samples at 15-min intervals over 24 h from six subjects receiving an isocaloric diet, and we measured adiponectin, leptin, sOB-R, and cortisol levels. Fourier and cross-correlation analyses were performed on these time series to study diurnal variations, and the Cluster7 program was used for pulsatility analysis. Circulating adiponectin and sOB-R levels exhibited ultradian pulsatility as well as a diurnal variation with a significant decline at night, reaching a nadir in the early morning. The 24-h variations of serum adiponectin and sOB-R were nearly identical and followed those of cortisol after a few hours, but were out-of-phase with leptin diurnal rhythms. These data suggest that adiponectin and sOB-R levels might be influenced by common regulatory factors and challenge the notion that cortisol may have a direct inhibitory effect on adiponectin in humans.

Activity Cycles↗

Adiponectin gene expression in subcutaneous adipose tissue of obese women in response to short-term very low calorie diet and refeeding.

Adiponectin is an adipocyte-derived protein suggested to be involved in energy homeostasis and in lipid and glucose metabolism. Little is known regarding the consequence of acute changes in energy balance on adiponectin mRNA expression in human adipose tissue. Using a real-time RT-PCR assay, we investigated the effects of 2-d very low calorie diet (VLCD) and subsequent refeeding on adiponectin mRNA expression in sc adipose tissue of morbidly obese women. Basal adiponectin mRNA abundance of the obese women showed a wide distribution (2.6-14.3 mRNA/18S rRNA; coefficient of variation, 51.2%) and was significantly lower than that of lean controls (P < 0.001). In the obese group, the VLCD caused a 33% rise (P < 0.01) in the average level of mRNA, whereas refeeding caused a 32.8% fall (P < 0.05). In contrast, the change in leptin mRNA expression with either VLCD or refeeding was not statistically significant. The obese subjects who showed an acute adiponectin mRNA response to the changes in energy intake had a higher basal level of adiponectin mRNA (P = 0.02) and a borderline-significantly lower body mass index compared with the subjects who showed no or weak adiponectin mRNA response. Insulin sensitivity of the responder subgroup significantly increased by 89% (P = 0.008) after the VLCD, whereas insulin sensitivity of the nonresponder subgroup only increased by 24% (P = 1.56). This study indicates that adiponectin mRNA in sc adipose tissue can acutely respond to short-term energy changes in some obese subjects. Both the levels of adiposity and insulin sensitivity may contribute to the variation in adiponectin gene expression in response to acute energy changes.

Adiponectin↗

Decreased plasma adiponectin concentrations are closely related to hepatic fat content and hepatic insulin resistance in pioglitazone-treated type 2 diabetic patients.

The effect of pioglitazone (PIO) on plasma adiponectin concentration, endogenous glucose production (EGP), and hepatic fat content (HFC) was studied in 11 type 2 diabetic patients (age, 52 +/- 2 yr; body mass index, 29.6 +/- 1.1 kg/m(2); HbA(1c), 7.8 +/- 0.4%). HFC (magnetic resonance spectroscopy) and basal plasma adiponectin concentration were quantitated before and after PIO (45 mg/d) for 16 wk. Subjects received a 3-h euglycemic insulin (100 mU/m(2).min) clamp combined with 3-[(3)H] glucose infusion to determine rates of EGP and tissue glucose disappearance (Rd) before and after PIO. PIO reduced fasting plasma glucose (10.0 +/- 0.7 to 7.2 +/- 0.6 mmol/liter, P < 0.01) and HbA(1c) (7.8 +/- 0.4 to 6.5 +/- 0.3%, P < 0.01) despite increased body weight (83.0 +/- 3.0 to 86.4 +/- 3.0 kg, P < 0.01). PIO improved Rd (6.6 +/- 0.6 vs. 5.2 +/- 0.5 mg/kg.min, P < 0.005) and reduced EGP (0.23 +/- 0.04 to 0.05 +/- 0.02 mg/kg.min, P < 0.01) during the 3-h insulin clamp. After PIO treatment, HFC decreased from 21.3 +/- 4.2 to 11.0 +/- 2.4% (P < 0.01), and plasma adiponectin increased from 7 +/- 1 to 21 +/- 2 micro g/ml (P < 0.0001). Plasma adiponectin concentration correlated negatively with HFC (r = -0.60, P < 0.05) and EGP (r = -0.80, P < 0.004) and positively with Rd before (r = 0.68, P < 0.02) pioglitazone treatment; similar correlations were observed between plasma adiponectin levels and HFC (r = -0.65, P < 0.03) and Rd after (r = 0.70, P = 0.01) pioglitazone treatment. EGP was almost completely suppressed after pioglitazone treatment; taken collectively, plasma adiponectin concentration, before and after pioglitazone treatment, still correlated negatively with EGP during the insulin clamp (r = -0.65, P < 0.001). In conclusion, PIO treatment in type 2 diabetes causes a 3-fold increase in plasma adiponectin concentration. The increase in plasma adiponectin is strongly associated with a decrease in hepatic fat content and improvements in hepatic and peripheral insulin sensitivity. The increase in plasma adiponectin concentration after thiazolidinedione therapy may play an important role in reversing the abnormality in hepatic fat mobilization and the hepatic/muscle insulin resistance in patients with type 2 diabetes.

Adiponectin↗

Adiponectin concentrations are influenced by renal function and diabetes duration in Pima Indians with type 2 diabetes.

Adiponectin is produced exclusively by adipocytes, and its serum concentration is inversely associated with adiposity. This study examines the relationship among diabetes, renal function, and serum adiponectin in Pima Indians. Serum adiponectin was measured in 1069 people in whom glycemia and renal function had been measured. Serum adiponectin, adjusted for age, sex, and body mass index, was lowest in those with impaired glucose regulation or diabetes of less than 10 yr duration and highest in those with normal glucose tolerance or diabetes of duration of at least 10 yr. Both urinary albumin to creatinine ratio (ACR) and serum creatinine were positively correlated with adiponectin (Spearman's r = 0.43; P < 0.0001, and r = 0.37; P < 0.0001, respectively) in diabetic subjects. After stratification by albuminuria (normoalbuminuria ACR < 30 mg/g, microalbuminuria ACR = 30-299 mg/g, and macroalbuminuria ACR >or= 300 mg/g), the highest adiponectin concentration was in the macroalbuminuria group (geometric mean = 9.6 microg/ml) and the lowest was in the normoalbuminuric group (geometric mean = 5.6 microg/ml). After adjustment for age, sex, body mass index, and diabetes duration, the serum adiponectin concentration in the macroalbuminuria group was significantly higher than in both other groups (P < 0.0001). Serum adiponectin is lowest in the presence of impaired glucose regulation and early diabetes. In the presence of diabetes, serum adiponectin is positively associated with abnormal renal function and diabetes duration.

Adiponectin↗

Gender differences of adiponectin levels develop during the progression of puberty and are related to serum androgen levels.

Adiponectin is an adipocytokine with profound antidiabetic and antiatherogenic effects that is decreased in obesity. With the increasing prevalence of obesity and the emergence of related disorders, including type 2 diabetes in children, the regulation of adiponectin and its relationship to childhood obesity is of great interest. In this study we aimed to elucidate the impact of gender, pubertal development, and obesity on adiponectin levels in children. We investigated two phenotypically characterized cohorts of 200 normal weight and 135 obese children and adolescents covering a wide range of age (3.4-17.9 yr) and body mass index (-2.1 to +4.8 sd score). In healthy lean boys, adiponectin levels significantly declined in parallel with physical and pubertal development, subsequently leading to significantly reduced adiponectin levels in adolescent boys compared with girls (5.6 +/- 0.5 vs. 7.1 +/- 0.5 mg/liter; P = 0.03). This decline was inversely related to testosterone (r = -0.42; P < 0.0001) and dehydroepiandrosterone sulfate (r = -0.20; P = 0.0068) serum concentrations and may account for the gender differences seen in adults. Using a stepwise forward multiple regression model, pubertal stage was the strongest independent predictor of adiponectin (r(2) = 0.206; P < 0.0001), with additional influences of body mass index sd score and testosterone. Adiponectin levels were decreased in obese children and adolescents compared with lean peers of corresponding age and pubertal stage (5.18 vs. 7.13 mg/liter; P = 0.015). In obese children, adiponectin levels were closely associated with parameters related to the metabolic syndrome, such as insulin resistance, hyperinsulinemia, blood pressure, and uric acid, in univariate and multivariate analyses, with the insulin sensitivity index being the strongest independent parameter identified by stepwise forward multiple regression (r(2) = 0.226; P < 0.0001). Hence, there is a strong association of adiponectin serum concentrations with obesity, pubertal development, and metabolic parameters in children indicating epidemiological and pathophysiological relevance already in childhood.

Adiponectin↗