Low Molecular Weight Adiponectin Research Articles

DO ADIPONECTIN ISOFORMS IN OLDER ADULTS WITH OR WITHOUT CORONARY ARTERY DISEASE DIFFER ACCORDING TO GLUCOSE TOLERANCE STATES AND LIFESTYLE FACTORS?

To the Editor: Adiponectin, an adipose tissue–derived protein, is an important regulator of insulin sensitivity and inflammation. The hormone plays a role in the suppression of the metabolic derangements that may result in type 2 diabetes mellitus (DM), obesity, atherosclerosis, and nonalcoholic fatty liver disease, and is an independent risk factor for metabolic syndrome.1 Adiponectin circulates in three isoforms: a trimer (low molecular weight (LMW)), a hexamer (trimer-dimer) of medium molecular weight (MMW), and a larger multimeric high-molecular-weight (HMW) isoform. Various studies have demonstrated that the HMW adiponectin isoform is primarily responsible for direct associations between adiponectin and several metabolic parameters, including insulin sensitivity and lower abdominal fat accumulation.2,3 We read with great interest the recently published study by Rizza and colleagues4 on adiponectin isoforms in elderly patients with or without coronary artery disease. The data from this study confirmed that adiponectin isoform levels are higher in older adults with coronary heart disease. The special importance of this article is that LMW adiponectin may have a protective role in this special group, but there are several points that merit discussion. As shown in the study design section, subjects without known type 2 DM underwent an oral glucose tolerance test, but the participants with prediabetes were evaluated as patients without DM, not as a separate group. This is important because circulating blood adiponectin levels are altered in subjects with disordered glucose metabolism.5 Smoking has been known to affect adipocytokines and to cause decreases in adiponectin levels. Moderate alcohol consumption is associated with higher adiponectin concentrations in healthy individuals.6 Furthermore, physically active older women have higher adiponectin concentrations,7 but Rizza and colleagues, in their research, did not check lifestyle-related factors, which may affect adipocytokine status.4 For these reasons, we would like to ask the authors whether they can present some new results by categorizing the patients according to confounders such as glucose tolerance status and lifestyle factors. This may provide readers with clearer information about adiponectin isoforms in older populations. We hope that this letter might prompt them to provide additional perspective on these questions. Conflict of Interest: The editor in chief has reviewed the conflict of interest checklist provided by the authors and has determined that the authors have no financial or any other kind of personal conflicts with this paper. Author Contributions: All authors contributed to the interpretation of the examined article and preparation of the letter. Sponsor's Role: None.

The proportion and metabolic effects of adiponectin multimeric isoforms in patients with chronic kidney disease on maintenance hemodialysis

Adiponectin circulates at least in three major forms of oligomeric complexes in plasma: a low-molecular-weight (LMW) trimer, a middle-molecular-weight (MMW) hexamer, and high-molecular-weight (HMW) adiponectin. Although it has been reported that adiponectin has the favorable metabolic properties for humans, the roles of these multimers in the patients with the end-stage renal disease (ESRD) were unidentified. We determined the level of total and multimeric adiponectin in 71 patients with nondiabetic ESRD treated with hemodialysis (HD) using a commercially available kit of enzyme-linked immunosorbent assay (ELISA). Correlations between metabolic variables and total and multimeric adiponectin were examined by Spearman's correlations analysis. Forward stepwise multiple linear regression analysis was also performed to determine the factors independently associated with them. Female patients had significantly higher total, HMW, and MMW levels than male patients did. According to homeostasis model of assessment of insulin resistance (HOMA-IR), value was associated not only with HMW but also with MMW and LMW. In multivariate analyses, HMW showed independently and positively associated with high-density lipoprotein cholesterol (HDL-C), body mass index (BMI), and sex as total adiponectin did. Unexpectedly, LMW adiponectin was independently and negatively correlated with TG and high-sensitive C-reactive protein (hs-CRP). Not only HMW adiponectin but also LMW adiponectin track with favorable metabolic effects in the patient with the ESRD.

Adiponectin isoforms, insulin resistance and liver histology in nonalcoholic fatty liver disease

Background Nonalcoholic fatty liver disease is associated with insulin resistance and low adiponectin levels. Adiponectin circulates as high-, medium- and low-molecular weight complexes, possibly exerting different insulin-sensitising effects. Aim We investigated adiponectin isoforms in nonalcoholic fatty liver disease in relation to liver disease severity and insulin resistance. Patients and methods Total adiponectin and isoform distribution were measured in 54 biopsy-proven, non-diabetic nonalcoholic fatty liver disease subjects, divided according to their fasting and 120-min glucose levels during an oral glucose tolerance test, as well as in 44 matched healthy controls. Insulin resistance/sensitivity was estimated in nonalcoholic fatty liver disease by the homeostasis model assessment and the oral glucose insulin sensitivity during oral glucose tolerance test. Total adiponectin and adiponectin isoforms were determined by in-house assays. Results Total adiponectin was reduced in nonalcoholic fatty liver disease (5.32 ± 1.85 mg/L vs. 9.11 ± 3.46 mg/L), with a relative abundance of high-molecular weight (34% vs. 47%) and low-molecular weight adiponectin (16% vs. 19%), coupled with dearth of medium-molecular weight adiponectin (50% vs. 34%) ( P < 0.001 for all comparisons). In nonalcoholic fatty liver disease, adiponectin did not differ in relation to homeostasis model assessment, but levels were remarkably higher in relation to oral glucose insulin sensitivity-determined insulin sensitivity. However, the distribution of isoforms did not vary with disease severity, BMI class, glucose regulation or insulin resistance. Conclusion Adiponectin levels are reduced in nonalcoholic fatty liver disease, without any significant contribution of isoform distribution to progressive liver disease.

Type 2 Diabetes in Octogenarians Is Associated with Decreased Low Molecular Weight Adiponectin

Background: Adiponectin circulates in the blood in three different multimer isoforms, of which the high molecular weight form (HMW) is presumed to mediate insulin sensitivity. We examined whether adiponectin oligomer distribution is associated with aging and type 2 diabetes (T2D) in octogenarians without characteristic features of metabolic syndrome. Methods: The study included 154 octogenarians (58 men, 96 women), 24 normoglycemic middle-aged controls (11 men, 13 women; mean age 44 years), and 33 middle-aged individuals (14 men, 19 women; mean age 55 years) with T2D. Based on oral glucose tolerance test 62 octogenarians had normal, 63 impaired glucose tolerance, and 29 octogenarians had newly detected T2D. Serum adiponectin multimer isoforms were measured after overnight fast by enzyme-linked immunosorbent assays. Results:Compared to the normoglycemic middle-aged control group, male normoglycemic octogenarians revealed significantly higher total adiponectin and all adiponectin isoforms. The same was true for females with the exception of low molecular weight (LMW) adiponectin, which was not statistically higher in octogenarians. Male and female octogenarians with T2D had significantly higher levels of total, HMW, and middle molecular weight (MMW) adiponectin, but not LMW adiponectin, than middle-aged individuals with T2D. Female, but not male, octogenarians revealed significantly lower total adiponectin than normoglycemic octogenarians. Compared with normoglycemic octogenarians, male and female octogenarians with T2D were characterized by significantly lower LMW adiponectin. In male and female octogenarians, total adiponectin and all multimer isoforms were directly correlated with HDL cholesterol. LMW adiponectin in octogenarians of both sexes was inversely correlated with glucose level at 2-hour oral glucose tolerance test. Conclusions: Serum levels of total adiponectin as well as its HMW and MMW isoforms were significantly higher in octogenarians with normoglycemia or T2D than in corresponding middle-aged control groups. In male and female octogenarians without metabolic syndrome, T2D was associated with lower LMW adiponectin, while the HMW and MMW isoforms were not statistically different.

Adiponectin Isoforms in Elderly Patients with or without Coronary Artery Disease

To study the distribution of adiponectin isoforms in a group of very old patients. Cross-sectional. Geriatric ambulatory clinic of the Department of Medicine at Policlinico "Tor Vergata." One hundred eight elderly adults (mean age 85.0+/-3.2) with or without a history of a previous myocardial infarction as proof of established coronary artery disease (CAD) at least 3 months before entry into the study. Accordingly, subjects were divided into CAD positive (CAD+, n=50) and CAD negative (CAD-, n=58). Assessment of adiponectin isoforms along with metabolic, lipid, and inflammatory profiles. CAD+ subjects had significantly higher levels of total adiponectin (Tot-Ad) and low-molecular-weight adiponectin (LMW-Ad) than CAD- subjects (P=.008 for both). LMW-Ad and high-sensitivity C-reactive protein were positively correlated, even after adjustment for waist circumference, sex, glomerular filtration rate, and presence of diabetes mellitus (correlation coefficient (r)=0.25, P=.05). This association was not confirmed when CAD+ subjects were analyzed alone. A positive association was found in CAD+ subjects between brain natriuretic peptide (BNP), high-molecular-weight adiponectin (HMW-Ad), and Tot-Ad (r=0.798 and r=0.795, P<.001 for all) but not LMW-Ad. Distribution of adiponectin isoforms differed in populations of elderly subjects according to the presence of coronary atherosclerosis. The data support the hypothesis for a protective role of LMW-Ad during aging, although additional studies are needed to definitively clarify whether LMW-Ad plays a protective role in older people with a history of CAD.

Increased plasma isoprostane is associated with visceral fat, high molecular weight adiponectin, and metabolic complications in obese children

Oxidative stress is considered to be increased in obese subjects. However, the association of oxidative stress with visceral adiposity and adiponectin level is not fully understood in children. Forty-four obese Japanese children and adolescents, 28 boys and 16 girls, with median age of 9.9 years [5.2-13.8 years], and the 28 age-matched non-obese healthy controls, 15 boys and 13 girls, were enrolled in this study. The median BMI Z scores were +2.21 [1.31-4.38] for the obese subjects and -0.72 [-2.11-1.31] for the control. Plasma concentrations of 8-epi-prostaglandin F₂α (isoprostane), a marker of oxidative stress, and adiponectin fractions were assayed using ELISA. 8-epi-PGF₂α levels were significantly higher in the obese group (37.1 [4.7-112.7], median and the range) than in the control (11.5 [4.5-27.3]). In a univariate analysis, concentrations of 8-epi-PGF₂α positively correlated with visceral adipose tissue area measured by computed tomography, waist circumference, serum triglycerides, alanine aminotransferase, insulin levels, and the homeostasis of minimal assessment of insulin resistance and inversely correlated with high-density-lipoprotein cholesterol and high-molecular weight (HMW) adiponectin. Total-, medium-, or low-molecular weight adiponectin fraction did not show a significant correlation with 8-epi-PGF₂α Forty of 44 obese children had one or more metabolic complications. The 8-epi-PGF[Formula: see text] levels also elevated with increasing numbers of obesity-related complications. These results suggest that oxidative stress is enhanced in relation to visceral fat accumulation and decreasing HMW adiponectin level in childhood obesity. Oxidative stress may be associated with the development of obesity-related complications.

Disparity in circulating adiponectin multimers between term and preterm infants

To study circulating levels and distribution of adiponectin multimers [low molecular weight (LMW)-, medium molecular weight (MMW)- and high molecular weight (HMW)-adiponectin] in preterm and full-term infants. Total serum adiponectin and its multimers were measured in 40 healthy infants at the age of one month and associations with anthropometric parameters [body weight and length, body mass index (BMI)], weight gain and metabolic indices (glucose, insulin) were examined. Twenty of the infants were born preterm (gestational age 33.2+/-1.6 weeks). LMW-adiponectin level and its fractional ratio to total adiponectin were significantly higher in full-term than in preterm infants (P<0.001 and P<0.01, respectively), whereas, MMW-adiponectin level and its ratio were significantly lower (P=0.03 and P=0.01, respectively). HMW-adiponectin did not differ significantly between full-term and preterm infants and accounted for almost 60% of total adiponectin levels in both groups. HMW-adiponectin, but not MMW adiponectin or LMW adiponectin, correlated significantly with anthropometric measurements, similarly to total adiponectin; in addition, HMW adiponectin correlated significantly with weight gain. HMW adiponectin is the most prevalent form in infants. Circulating levels and distribution of MMW- and LMW-adiponectin differ between full-term and preterm infants, but the role of these adiponectin multimers needs to be studied further.

Association of adiponectin multimers with Barrett’s oesophagus

Objective:Barrett’s oesophagus is associated with abdominal obesity. Adiponectin is a peptide that is secreted from adipocytes and circulates in three multimeric forms: low molecular weight (LMW), middle molecular weight (MMW),...

Changes in adiponectin multimer distribution in response to atorvastatin treatment in patients with type 2 diabetes

Multimeric high molecular weight (HMW) forms of adiponectin were previously shown to be inversely associated with the extent of atherosclerosis in males and are down-regulated in patients with the metabolic syndrome and type 2 diabetes. In this study, potential influences of atorvastatin therapy on adiponectin multimer distribution were studied in patients with type 2 diabetes. The effect of 40 mg atorvastatin on HMW, medium molecular weight (MMW), and low molecular weight (LMW) isoforms of adiponectin were investigated in 75 patients (23 females; 52 males) with type 2 diabetes in an 8-week-long, placebo-controlled and randomized study. Adiponectin multimeric isoforms were detected by Western blot analysis. After atorvastatin therapy the median serum concentration of HMW adiponectin increased significantly by 42.3% (1.68 vs. 2.39 microg/ml; P < 0.001), while concentrations of MMW adiponectin and LMW adiponectin significantly decreased by 20.8% and 23.2%, respectively (MMW: 3.31 vs. 2.62 microg/ml, P = 0.047; LMW: 0.56 vs. 0.43 microg/ml, P = 0.033). Median total adiponectin levels were not significantly altered by atorvastatin treatment (6.0 vs. 6.2 microg/ml, P = 0.898). Consequently, the HMW: total-adiponectin ratio significantly increased by 25.0% (0.40 vs. 0.50; P = 0.013). Atorvastatin therapy is associated with significant changes in adiponectin multimer distribution in patients with type 2 diabetes. Since total adiponectin levels were not affected by intervention, atorvastatin may shift adiponectin size towards the HMW form.

Induction of chemokine expression by adiponectin in vitro is isoform dependent

Adiponectin is reported to have both proinflammatory and anti-inflammatory effects. Because adiponectin circulates in isoforms of various sizes and some responses to adiponectin are isoform dependent, it was postulated that the proinflammatory effects of adiponectin may be isoform specific. To test this theory, peripheral blood mononuclear cells (PBMCs), microvascular endothelial cells (MVECs), and human glomerular mesangial cells (HMCs) were treated with high-molecular-weight (HMW) or low-molecular-weight (LMW) recombinant human adiponectin, and chemokine production was measured. The PBMCs were isolated from healthy volunteers by density gradient centrifugation of ethylenediaminetetraacetic acid (EDTA) anticoagulated whole blood through endotoxin-free Ficoll (General Electric Healthcare Bio-Sciences, Uppsala, Sweden). The MVECs were of dermal origin, and the HMCs were isolated from kidneys not suitable for transplantation. Overnight (16 h) incubation with HMW adiponectin (0.01-1 microg/mL for PBMCs; 5-20 microg/mL for MVECs and HMCs) induced a dose-dependent increase in production of monocyte chemoattractant protein-1 and interleukin-8 by PBMCs and MVECs, but it had no effect on HMC chemokine production (n=3-5). LMW adiponectin at the same concentrations did not induce chemokine production in any of the cell types tested, and it did not block cytokine-induced chemokine production by PBMCs or MVECs (n=3-5). These in vitro data suggested that the HMW adiponectin isoform is proinflammatory. To examine the possibility of a relationship between HMW adiponectin and inflammation in vivo, the urine of patients with systemic lupus erythematosus (SLE) and kidney involvement, which was shown previously to contain immunoreactive adiponectin, was examined for the presence of specific adiponectin isoforms by nondenaturing gel electrophoresis. HMW adiponectin was found in the urine of patients with active lupus nephritis. Therefore, HMW adiponectin may contribute to the renal inflammation of SLE.

The Ratio of High-Molecular Weight Adiponectin and Total Adiponectin Differs in Preterm and Term Infants

Adiponectin consists of three subspecies (high-, middle- and low-molecular weight adiponectin). Among these, high-molecular weight adiponectin (H-adn) is suggested to be an active form of this protein. To assess the relationship between H-adn and postnatal growth in preterm infants (PIs), serum H-adn and total adiponectin (T-adn) were measured in 46 PIs at birth and at corrected term, and 26 term infants (TI) at birth. T-adn and H-adn concentrations, and the ratio of H-adn to T-adn (H/T-adn) were significantly greater in TI and PI at corrected term than in PI at birth (p < 0.001). T-adn and H-adn concentrations in PI at corrected term were similar to those in TI, but H/T-adn in PI at corrected term was less than that in TI (p < 0.02). Stepwise multiple regression analysis revealed that the factors contributing to H/T-adn and serum concentrations of T- and H-adn in PI at corrected term were different from those in TI. These data suggest that quality of early postnatal growth in PIs is different from that in normally developed TI. Postnatal growth accompanying adipose tissue similar to TI may be important for PI to prevent future development of cardiovascular disease.

Adiponectin Oligomers and Ectopic Fat in Liver and Skeletal Muscle in Humans

We aimed at determining which circulating forms of the adipokine adiponectin that increases lipid oxidation in liver and skeletal muscle are related to ectopic fat in these depots in humans. Plasma total-, high-molecular weight (HMW)-, middle-molecular weight (MMW)-, and low-molecular weight (LMW) adiponectin were quantified by an enzyme-linked immunosorbent assay. Their relationships with liver- and intramyocellular fat, measured using (1)H magnetic resonance spectroscopy, were investigated in 54 whites without type 2 diabetes. Liver fat, adjusted for gender, age, and total body fat, was associated only with HMW adiponectin (r = -0.35, P = 0.012), but not with total-, MMW-, or LMW adiponectin. In addition, subjects with fatty liver (liver fat > or =5.56%, n = 15) had significantly lower HMW- (P = 0.04), but not total-, MMW-, or LMW adiponectin levels, compared to controls (n = 39). Similarly, intramyocellular fat correlated only with HMW (r = -0.32, P = 0.039), but not with the other circulating forms of adiponectin. These data indicate that, among circulating forms of adiponectin, HMW is strongly related to ectopic fat, thus possibly representing the form of adiponectin regulating lipid oxidation in liver and skeletal muscle.

Altered molecular weight forms of adiponectin in hypertension.

An important link between adiponectin and hypertension has been proposed in clinical studies. In the circulation, adiponectin is predominantly present in multimeric complexes, of which high-molecular weight (HMW) adiponectin is thought to represent the biological active form. The authors investigated which role the different multimeric adiponectin isoforms play in context with hypertension as compared to total adiponectin levels. Fifty (19 normotensive/31 hypertensive) patients were included in the study. Total adiponectin and adiponectin multimers were determined by enzyme-linked immunosorbent assay and western blot. The authors analyzed associations between adiponectin multimer levels and blood pressure. Total adiponectin concentrations were not significantly different between hypertensive and normotensive patients (6.8+/-2.3 vs 7.5+/-4.2 microg/mL). HMW adiponectin was significantly lower (P<.05) and low-molecular weight adiponectin was significantly higher (P<.01) in hypertensive than in normotensive persons (3.8+/-1.7 vs 5.2+/-3.0 microg/mL and 0.9+/-0.5 vs 1.8+/-0.9, respectively). Low molecular weight was an independent predictor for the presence of hypertension (effect coefficient: 0.160-0.445; P<.001) in multivariate analyses. These results suggest that the composition of the molecular weight forms of adiponectin in hypertension are characterized by reduced HMW adiponectin, the proposed major active form of adiponectin, and increased low-molecular weight adiponectin. Moreover, the latter represents an independent predictor of prevalent hypertension, suggesting an association between adiponectin multimer composition and hypertension.

Adiponectin Multimers and Metabolic Syndrome Traits: Relative Adiponectin Resistance in African Americans

African Americans (AAs) tend to have lower total adiponectin levels compared to European Americans (EA); however, it is not known whether race affects adiponectin multimer distribution and their relationships to metabolic traits. We measured total adiponectin, high molecular weight (HMW), low molecular weight (LMW) (i.e., hexamer), and trimer adiponectin in 132 normoglycemic premenopausal women (75 AAs, 57 EAs), together with measures of total and abdominal fat, plasma lipids, insulin sensitivity (S(i)), and genetic admixture estimates. We found that lower total adiponectin in AAs was explained by reduced LMW, and trimer forms because levels of HMW did not differ between races. In EAs, HMW was highly correlated with multiple metabolic syndrome traits. In contrast, the LMW and trimer forms were most highly correlated with metabolic traits in AAs, including abdominal adiposity, lipids, and S(i). At similar levels of visceral adiposity, AAs exhibited significantly lower LMW adiponectin than EAs. Similarly, at comparable levels of HMW and LMW adiponectin, AAs were more insulin resistant than their EA counterparts. In conclusion, (i) serum adiponectin is lower in AAs predominantly as a result of reduced concentrations of LMW and trimers multimeric forms; (ii) LMW and trimer, not HMW, are most broadly correlated with metabolic traits in AAs. Thus, HMW adiponectin may exert less bioactivity in explaining the metabolic syndrome trait cluster in populations of predominant African genetic background.

Preatherosclerosis and Adiponectin Subfractions in Obese Adolescents

We evaluated total adiponectin, high-molecular weight (HMW), medium-molecular weight (MMW), low-molecular weight (LMW) adiponectin subfractions, clinical parameters, routine lab parameters, lipids, metabolic, inflammatory biomarkers, and intima-media thickness (IMT) of common carotid arteries in 70 obese juveniles and adolescents with preatherosclerosis and 55 normal weight controls of similar age and gender distribution. Compared with the controls, the obese probands had a significantly increased IMT (P < 0.001) and elevated ultra-sensitive C-reactive protein (P < 0.001) indicating early vascular burden. Total and HMW adiponectin were significantly decreased in the obese cohort. The ratio between HMW and total adiponectin was significantly decreased in obese probands whereas the LMW/total adiponectin ratio was increased. Overall, total-, HMW, and MMW adiponectin were significantly negatively correlated with carotid IMT. The HMW/total adiponectin ratio correlated significantly negatively, and the LMW/total adiponectin ratio significantly positively with the IMT. Furthermore, HMW adiponectin was significantly positively correlated with high-density lipoprotein (HDL)-cholesterol and serum apolipoprotein A1, and negatively with BMI, triglycerides, homeostatic model assessment (HOMA)-index, leptin, liver transaminases, and uric acid. This remained stable after controlling for gender. Multiple regression analysis of body measures and all other lab parameters showed the strongest correlation between HMW adiponectin and carotid IMT (beta = -0.35, P < 0.001). Taken together, our study provides the first evidence that preatherosclerosis in obese juveniles and adolescents is associated with altered subfractions of adiponectin, whereas after multiple testing the HMW subfraction showed a better correlation to IMT compared with total adiponectin.

Increase in high molecular weight adiponectin by bariatric surgery‐induced weight loss

To determine the changes in adiponectin multimers upon marked weight loss. Plasma samples were obtained preoperatively and 3, 6, 12 and 24 months after surgery from 12 obese subjects undergoing weight loss-inducing bariatric surgery. Seven non-operated obese subjects served as controls. Plasma levels of adiponectin multimers were determined by protease digestion and Enzyme-Linked ImmunoSorbent Assay (ELISA) detection. In addition, adiponectin multimers were assessed by western blotting. In patients with weight loss after surgery but not in controls, total adiponectin and high molecular weight (HMW) adiponectin steadily increased during the observation period. Twenty-four months after surgery, the increase in total and HMW adiponectin was 2.2 +/- 0.46 and 1.4 +/- 0.3 microg/ml, respectively. In contrast, plasma concentrations of middle and low molecular weight adiponectin remained unchanged. The increase in plasma adiponectin levels observed 24 months after bariatric surgery depended on continuous weight loss and was completely attributable to the HMW complex.

β-Conglycinin Embeds Active Peptides That Inhibit Lipid Accumulation in 3T3-L1 Adipocytes in Vitro

Obesity is a worldwide health concern because it is a well-recognized predictor of premature mortality. The objective was to identify soybean varieties that have improved potential to inhibit fat accumulation in adipocytes by testing the effects of soy hydrolysates having a range of protein subunit compositions on lipid accumulation and adiponectin expression in 3T3-L1 adipocytes. The results showed that differences in the protein distribution of 15 soy genotypes led to different potentials for the reduction of fat accumulation. The inhibition of lipid accumulation of soy alcalase hydrolysates in 3T3-L1 adipocytes ranged from 29 to 46%. Soy hydrolysates made from genotypes with 45.3 +/- 3.3% of total protein as beta-conglycinin, on average, showed significantly higher inhibition of lipid accumulation compared to those with 24.7 +/- 1.5% of extracted total protein as beta-conglycinin. Moreover, after in vitro simulated digestion with pepsin-pancreatin of the soy alcalase hydrolysates, 86% of the original activity remained. Adiponectin expression was induced in 3T3-L1 adipocytes treated with 15 soy hydrolysates up to 2.49- and 2.63-fold for high and low molecular weight adiponectin, respectively. The inhibition of lipid accumulation calculated from a partial least squares (PLS) analysis model correlated well with experimental data (R(2) = 0.91). In conclusion, it was feasible to differentiate soy varieties on the basis of the potential of their proteins to reduce fat accumulation using a statistical model and a cell-based assay in vitro. Furthermore, beta-conglycinin embeds more peptides than glycinin subunits that inhibit lipid accumulation and induce adiponectin in 3T3-L1 adipocytes. Therefore, soy ingredients containing beta-conglycinin may be important food components for the control of lipid accumulation in adipose tissue.

Adiponectin multimer distribution in patients with familial combined hyperlipidemia

Adiponectin is secreted from adipocytes in different multimers, of which the high molecular weight (HMW) form is supposed to mediate favorable metabolic and anti-atherogenic effects. We determined adiponectin multimers in 29 female and 22 male patients with familial combined hyperlipidemia (FCH) and 51 age-, gender-, and BMI-matched controls in relation to cardiovascular disease (CVD). We observed a clear sexual dimorphism of total adiponectin and its multimers. Female, but not male, FCH patients had significant lower total adiponectin and both HMW and low molecular weight (LMW) adiponectin than controls. The adiponectin sensitivity index (ASI), reflected by HMW/total adiponectin, and the LMW/HMW adiponectin ratio did not differ significantly between FCH females and control females. However, FCH females with CVD exhibited significantly lower ASI (34.2±10.1% vs 46.0±7.1%) and higher LMW/HMW ratio (1.5±0.8 vs 0.7±0.3) compared to FCH females without CVD, reflecting a more atherogenic adiponectin multimer distribution.

Nuchal thickness of subcutaneous adipose tissue is tightly associated with an increased LMW/total adiponectin ratio in obese juveniles

Subcutaneous adipose tissue (SAT) topography contributes significantly to metabolic risk profiles and atherosclerotic vascular burden in obese adults. However, little information exists concerning individual risk profiles in early phases of obesity found in childhood and adolescence. Thus, the rationale of this study was to evaluate possible impacts of SAT topography in obese juveniles on adiponectin subfractions, with special emphasis on low molecular weight (LMW) adiponectin. To address this, we analysed associations between lipometry, early metabolic and preatherosclerotic symptoms and adiponectin subfractions in 71 obese juveniles and 75 normal weight controls of similar age and gender distribution.Compared to the controls, obese juveniles had a significantly decreased ratio between high molecular weight (HMW) and total adiponectin whereas the LMW/total adiponectin ratio was increased. The LMW/total adiponectin ratio correlated significantly positively with the SAT thickness of trunk-located lipometer measure points neck, biceps, upper back, lower back, body mass index (BMI), and waist circumference. Further significant positive correlations were seen with systolic blood pressure, intima media thickness (IMT) of common carotid arteries, and metabolic parameters such as HOMA-index, leptin, oxidized LDL (oxLDL), liver transaminases, and HDL-triglycerides. This remained stable after controlling for gender. A stepwise multiple regression analysis encompassing all these variables revealed a robust positive association between LMW/total adiponectin ratio and nuchal SAT thickness defined by the lipometer measure point neck.Taken together, our data provide the first evidence that nuchal SAT thickness is tightly positively associated with an increased LMW/total adiponectin ratio.

Plasma high- but not low-molecular weight adiponectin is positively associated with resting energy expenditure in male non-diabetic hemodialysis patients

Plasma high- but not low-molecular weight adiponectin is positively associated with resting energy expenditure in male non-diabetic hemodialysis patients