Adiponectin serum levels correlate with insulin resistance in type 2 diabetic patients

Cigarette Smoking and Hyperglycaemia in Diabetic Patients

BACKGROUND:

The incidence rate of diabetes mellitus has increased throughout the year. Various studies indicate that smoking may affect glucose metabolism and cause hyperglycemia in diabetes mellitus. This study aimed to compare the blood glucose and HbA1c level in diabetic smoking patients and non-smoking diabetic patients.

METHODS:

This study used the cross-sectional approach. The study population consisted of 30 diabetic smoking patients and 30 non-smoking diabetic patients. The diabetes history and the smoking status of the study population obtained by questionnaire-based interview, the blood glucose and HbA1c level were measured by hexokinase and immunoturbidimetry method using cobas 6000 analyser module c501 (Roche Diagnostics, Switzerland).

RESULTS:

The result in this study showed the fasting blood glucose, postprandial blood glucose, and HbA1c were higher by 23.64 mg/dl (p = 0.325), 58.00 mg/dl (p = 0.016), 0.39% (p = 0.412) in smoking diabetic patients compared to non-smoking diabetic patients. After statistical analysis, there was a significant difference (p < 0.05) of postprandial glucose level between smokers group and non-smokers group, but the non-significant difference of fasting blood glucose and HbA1c

CONCLUSIONS:

This study concluded that there was a significant difference in postprandial glucose level between smokers group and non-smokers group but the non-significant difference of fasting blood glucose and HbA1c.

Single Nucleotide Polymorphism at +276 G>T of the Adiponectin Gene and Plasma Adiponectin Level in Myanmar Type 2 Diabetic Patients

Objective

The aim of the study was to investigate the association between single nucleotide polymorphisms (SNP) at rs 1501299 (SNP+276 G>T) of the adiponectin gene and plasma adiponectin levels in type 2 diabetes mellitus (T2DM) patients in Myanmar.

Methodology

One hundred T2DM patients and 104 non-diabetic subjects were included in this cross-sectional analytical study. Genotype frequencies were determined by polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) method. Plasma adiponectin level was measured by enzyme-linked immunosorbent assay (ELISA).

Result

Genotype frequencies (GG, GT, TT) of SNP+276 in diabetic patients were 39%, 48% and 13%, respectively. The GT and TT genotypes were more frequent in T2DM patients (OR 1.98, 95% CI, 1.10-3.55; p=0.02 and OR 4.07, 95% CI, 1.34-12.3; p=0.01), respectively. The T allele of SNP+276 was significantly associated with T2DM (OR 1.96, 95% CI, 1.27-3.01; p=0.002). Mean plasma adiponectin level was significantly lower than in T2DM patients (27.41±16.7 μg/mL) compared to non-diabetic subjects (37.19±26.77 μg/mL) (p=0.002).

Conclusion

SNP+276 at rs 1501299 of the adiponectin gene was associated with type 2 diabetes and low plasma adiponectin levels in this Myanmar population.

Association of adiponectin with cognitive function precedes overt diabetes in the Brazilian Longitudinal Study of Adult Health: ELSA

BACKGROUND

Adiponectin is an insulin-sensitizer adipocytokine endowed with neuroprotective actions. Whether adiponectin regulates neuronal functioning toward delaying cognitive decline independently of the glucose metabolism disturbance has been poorly explored. This study evaluated if the performance in cognitive tests was associated with adiponectin levels prior the development of type 2 diabetes in middle-aged individuals.

METHODS

A sample of 938 non-diabetic participants of ELSA had their cognitive function assessed by the CERAD delayed word recall test, the verbal fluency test and the trail making test. Stepwise multiple linear regression using forward selection had the response to cognitive tests as the dependent variable and adiponectin as the independent variable of main interest, adjusted for glucose tolerance status and confounders.

RESULTS

Mean age was 45.7 ± 4.9 years, 54.5% were women, 43.0% had high education level, 59.3% weight excess and 70.0% prediabetes. In crude model, only the delayed recall memory was associated with adiponectin levels. In an initial regression model, delayed recall memory remained independently associated with adiponectin levels and prediabetes. After complete adjustments, adiponectin but not prediabetes maintained independently associated with delayed recall memory (β 0.067; 95% CI 0.006-0.234; p = 0.040). On the other hand, learning memory showed to be associated with prediabetes (β 0.71 95% CI 0.17; 1.24; p = 0.009) but not with adiponectin.

CONCLUSIONS

The association of memory with adiponectin in middle-aged individuals, prior overt diabetes, suggests that this adipocytokine could anticipate cognitive impairmentρ detection, when preventive strategies could be more effectively implemented. The usefulness of adiponectin to identify increased risk for cognitive dysfunction before advanced age needs to be prospectively investigated in ELSA cohort.

Adiponectin, Leptin, and Leptin Receptor in Obese Patients with Type 2 Diabetes Treated with Insulin Detemir

The aim of the present study is to quantitatively assess the expression of selected regulatory molecules, such as leptin, leptin receptor, and adiponectin in the blood of obese patients with type 2 diabetes both before treatment and after six months of pharmacological therapy with the long-lasting insulin analogue, insulin detemir. A significant decrease in the analysed regulatory molecules, i.e., leptin receptor and adiponectin, was found in blood plasma of the patients with untreated type 2 diabetes. These changes were accompanied by an increase in plasma leptin concentrations. Insulin treatment resulted in the normalization of plasma leptin receptor and adiponectin concentrations. The circulating leptin level did not change following anti-diabetic therapy with insulin detemir. Gender was a significant factor modifying the circulating level of all the analysed regulatory active compounds. Bioinformatic analysis was performed using Matlab with the Signal Processing Toolbox. The conducted discriminant analysis revealed that the leptin receptor, Δw(19), and adiponectin, Δw(21), were the parameters undergoing the most significant quantitative changes during the six-month therapy with insulin detemir. The conducted examinations indicated the contribution of adipocytokines—the biologically-active mediators of systemic metabolism, such as leptin and adiponectin in the pathomechanism of disorders being the basis for obesity which leads to development of insulin resistance, which, in turn, results in the occurrence of type 2 diabetes.

Adiponectin attenuates high glucose-induced apoptosis through the AMPK/p38 MAPK signaling pathway in NRK-52E cells

Excessive apoptosis of proximal tubule cell is closely related to the development of diabetes. Recent evidence suggests that adiponectin (ADPN) protects cells from high glucose induced apoptosis. However, the precise mechanisms remain poorly understood. We sought to investigate the role of p38 mitogen-activated protein kinase (p38 MAPK) and AMP activated protein kinase (AMPK) in anti-apoptotic of adiponectin under high glucose condition in rat tubular NRK-52E cells. Cells were cultured in constant and oscillating high glucose media with or without recombinant rat adiponectin for 48 h. Cell counting kit-8 (CCK-8) was used to detect cell viability, flow cytometry and Hoechst Staining were applied to investigate cell apoptosis, and western blotting was used to examine protein expression, such as phospho-AMPK and phospho-p38MAPK. Exposure to oscillating high glucose exerted lower cell viability and higher early apoptosis than constant high glucose, which were both partially prevented by adiponectin. Further studies revealed that adiponectin suppressed p38MAPK phosphorylation, but led to an increase in AMPK α phosphorylation. Compared to stable high glucose group, blockage of p38MAPK cascade with SB203580 attenuated apoptosis significantly, but failed to affect the phosphorylation level of AMPK. While AMPK inhibitor, Compound C, increased apoptosis and remarkably inhibited the p38MAPK phosphorylation. Adiponectin exert a crucial protective role against apoptosis induced by high glucose via AMPK/p38MAPK pathway.

Adiponectin and pro-inflammatory cytokines are modulated in Vietnamese patients with type 2 diabetes mellitus

AIMS/INTRODUCTION

Adipose tissue-derived hormones are associated with metabolic disorders including type 2 diabetes mellitus. The present study investigated the levels of adiponectin and pro-inflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin-1 beta (IL-1β) and IL-10 in Vietnamese patients with type 2 diabetes mellitus, and their correlations with clinical parameters of overweight and type 2 diabetes mellitus.

MATERIALS AND METHODS

Based on body mass index, 73 patients with type 2 diabetes mellitus were categorized either as overweight or non-overweight. As healthy controls, 57 overweight and non-overweight individuals without type 2 diabetes mellitus were included. The adiponectin, TNF-α, IL-1β and IL-10 levels were measured in the sera samples in all study participants by enzyme-linked immunosorbent assay and were correlated with clinical parameters.

RESULTS

The adiponectin levels were lower in patients with type 2 diabetes mellitus (2.5 ± 1.5 μg/mL) compared with controls (16 ± 18.6 μg/mL; P < 0.0001), and were decreased in overweight individuals compared with those who were not overweight. The TNF-α and IL-1β levels were increased, whereas the IL-10 levels were decreased in patients with type 2 diabetes mellitus and in overweight controls compared with non-overweight controls (P < 0.0001). The adiponectin levels were correlated with the TNF-α, IL-1β, IL-10 levels, and the clinical parameters of overweight and type 2 diabetes mellitus. The quantitative insulin sensitivity check index and homeostasis model assessment insulin resistance indexes were correlated with the relative ratios of adiponectin/TNF-α, adiponectin/IL-1β, adiponectin/IL-10, TNF-α/IL-10 and IL-1β/IL-10.

CONCLUSIONS

Adiponectin and pro-inflammatory cytokines are associated with type 2 diabetes mellitus, and might serve as a prognostic marker and a therapeutic intervention for overweight-related type 2 diabetes mellitus.

Leptin and adiponectin: pathophysiological role and possible therapeutic target of inflammation in ischemic stroke

Stroke is a multifactorial disease contributing to significant noncommunicable disease burden in developing countries. Risk of stroke is largely a consequence of morbidities of diabetes, obesity, hypertension, and heart diseases. Incidence of stroke is directly proportional to body mass index. Adipose tissue stores energy as well as acts as an active endocrine organ, which secretes numerous humoral factors. Adiponectin and leptin are the commonest adipocytokines and have been invariably linked to the development of coronary heart disease and may be involved in the underlying biological mechanism of stroke. Leptin and adiponectin mediate proatherogenic and antiatherogenic responses, respectively, and hence, determining the plasma or serum levels of leptin and adiponectin alone or in combination may act as a novel prognostic biomarker for inflammation and atherosclerosis in stroke. This review addresses leptin- and adiponectin-mediated inflammatory mechanism in ischemic stroke and their potential as therapeutic targets.

Antihyperglycemic Effect of Rosa Damascena is Mediated by PPAR.γ Gene Expression in Animal Model of Insulin Resistance

Insulin resistance is a condition in which insulin signaling and action are impaired in insulin sensitive tissues and result in hyperglycemia, hyperlipidemia, and type 2 diabetes mellitus. Our previous studies have shown that Rosa damascena has antihyperglycemic effects on diabetic and normal rats. Therefore, we conducted a study to evaluate the effect of this medicinal plant on insulin sensitivity in rats. This study was performed on high fructose diet insulin resistant rats and pioglitazone, an insulin sensitizing drug, was used as a positive control. Insulin resistance was developed in animals by high fructose diet within six weeks. Then, Rosa damascena extract and pioglitazone were administered by gavage for two weeks and results were compared with two control groups. After treatment period, serum glucose, insulin, adiponectin, triglyceride, and cholesterol were assayed in fasting state. Plasma free fatty acid profile was analyzed by GC. Liver PPAR.γ and muscle GLUT.4 gene expressions were assessed by real time PCR and western blotting. Animals were treated with rosa damascena extract showed levels of insulin (42 ± 2.7 pmol/L). adiponectin (5.6±0.17 μg/mL). glucose (129±4.7 mg/dL). and triglyceride (75 ± 9 mg/dl) which were significantly improved as compared with control group insulin (137 ± 34 pmol/L), adiponectin (3.9±0.15 μg/mL). glucose (187±15 mg/dL). and triglycerides (217±18 mg/dL). PPARγ protein level was also significantly increased in Rosa damascene treated group. Our results demonstrated that rosa damascena extract has useful effects on insulin resistant animals and by increasing insulin sensitivity can be considered as a potential agent in control of diabetes.

Investigating Susceptibility to Diabetes Using Features of the Adipose Tissue in Response to In Utero Polycyclic Aromatic Hydrocarbons Exposure

BACKGROUND

In recent times, there has been an increase in the incidence of type 2 diabetes mellitus (T2DM) particularly in children. Adipocyte dysfunction provide a critical link between obesity and insulin resistance resulting in diabetes outcome. Further, environmental chemical exposure during early years of life might be a significant contributing factor to the increase in the incidence of T2DM. This study tests the idea that exposure to environmental contaminants (2-aminoanthracene [2AA]) in utero will show effects in the adipose tissue (AT) that signify T2DM vulnerability. 2AA is a polycyclic aromatic hydrocarbon found in a variety of products.

METHODS

To accomplish the study objective, pregnant dams were fed various amounts of 2AA adulterated diets from gestation through postnatal period. The neonates and older offspring were analyzed for diabetic-like genes in the ATs and analysis of serum glucose. Furthermore, weight monitoring, histopathology and immunohistochemical (IHC) staining for CD68 in AT, adipocyte size determination and adiponectin amounts in serum were undertaken.

RESULTS

Up-regulation of adiponectin and interleukin-6 genes were noted in the pups and older rats. Combination of intrauterine 2AA toxicity with moderate high fat diet exhibited gene expression patterns similar to those of the neonates. Elevated serum glucose levels were noted in treated groups. IHC of the AT indicated no significant malformations; however, CD68+ cells were greater in the animals treated to 2AA. Similarly, mean sizes of the adipocytes were larger in treated and combined 2AA and moderate high fat animals. Adiponectin was reduced in 2AA groups.

CONCLUSION

From the preceding, it appears intrauterine 2AA disturbance, when combined with excess fat accumulation will lead to greater risk for the diabetic condition.