Correlation of plasma resistin with obesity and insulin resistance in type 2 diabetic patients

Correlation of plasma adipokines with endometrial atypical hyperplasia and type I/II endometrial cancer

The aim of the study was to systematically explore the relationships between various adipokines and risks of endometrial atypical hyperplasia (EAH), type I endometrial cancer (EC), and type II EC. We enrolled 219 patients in this study, including 39 EAH, 87 type I EC, 38 type II EC and 55 control individuals. We subsequently explored the association of adipokine levels and the leptin-to-adiponectin (L/A) ratio with EAH, type I EC, and type II EC. The plasma leptin level and L/A ratio were significantly higher in the EAH group than in the control group (p = 0.012). Leptin, resistin, vaspin, and visfatin levels were significantly higher in the type I EC group; however, the adiponectin level was lower in the type I EC, which resulted in a higher L/A ratio. Notably, the L/A ratio and visfatin level in the type II EC group were significantly higher. Multiple logistic regression analysis revealed that a higher leptin level was significantly associated with a higher EAH risk (p = 0.012). Higher leptin level (p = 0.042) and L/A ratio (p = 0.027) were significantly associated with an increased type I EC risk. By contrast, higher leptin (p = 0.059) and visfatin (p = 0.003) levels, higher L/A ratio (p = 0.033), and lower adiponectin level (p = 0.042) were associated with an increased type II EC risk. We suggested that adipokines are potentially correlated with EAH and EC risks.

The cause-effect relation of tuberculosis on incidence of diabetes mellitus

Tuberculosis (TB) is one of the oldest human diseases and is one of the major causes of mortality and morbidity across the Globe. Mycobacterium tuberculosis (Mtb), the causal agent of TB is one of the most successful pathogens known to mankind. Malnutrition, smoking, co-infection with other pathogens like human immunodeficiency virus (HIV), or conditions like diabetes further aggravate the tuberculosis pathogenesis. The association between type 2 diabetes mellitus (DM) and tuberculosis is well known and the immune-metabolic changes during diabetes are known to cause increased susceptibility to tuberculosis. Many epidemiological studies suggest the occurrence of hyperglycemia during active TB leading to impaired glucose tolerance and insulin resistance. However, the mechanisms underlying these effects is not well understood. In this review, we have described possible causal factors like inflammation, host metabolic changes triggered by tuberculosis that could contribute to the development of insulin resistance and type 2 diabetes. We have also discussed therapeutic management of type 2 diabetes during TB, which may help in designing future strategies to cope with TB-DM cases.

Dysfunctions, molecular mechanisms, and therapeutic strategies of pancreatic β-cells in diabetes

Pancreatic beta-cell death has been established as a critical mediator in the progression of type 1 and type 2 diabetes mellitus. Beta-cell death is associated with exacerbating hyperglycemia and insulin resistance and paves the way for the progression of DM and its complications. Apoptosis has been considered the primary mechanism of beta-cell death in diabetes. However, recent pieces of evidence have implicated the substantial involvement of several other novel modes of cell death, including autophagy, pyroptosis, necroptosis, and ferroptosis. These distinct mechanisms are characterized by their unique biochemical features and often precipitate damage through the induction of cellular stressors, including endoplasmic reticulum stress, oxidative stress, and inflammation. Experimental studies were identified from PubMed literature on different modes of beta cell death during the onset of diabetes mellitus. This review summarizes current knowledge on the crucial pathways implicated in pancreatic beta cell death. The article also focuses on applying natural compounds as potential treatment strategies in inhibiting these cell death pathways.

AMP-activated protein kinase is a key regulator of obesity-associated factors

An imbalance between caloric intake and energy expenditure leads to obesity. Obesity is an important risk factor for the development of several metabolic diseases including insulin resistance, metabolic syndrome, type 2 diabetes mellitus, and cardiovascular disease. So, controlling obesity could be effective in the improvement of obesity-related diseases. Various factors are involved in obesity, such as AMP-activated protein kinases (AMPK), silent information regulators, inflammatory mediators, oxidative stress parameters, gastrointestinal hormones, adipokines, angiopoietin-like proteins, and microRNAs. These factors play an important role in obesity by controlling fat metabolism, energy homeostasis, food intake, and insulin sensitivity. AMPK is a heterotrimeric serine/threonine protein kinase known as a fuel-sensing enzyme. The central role of AMPK in obesity makes it an attractive molecule to target obesity and related metabolic diseases. In this review, the critical role of AMPK in obesity and the interplay between AMPK and obesity-associated factors were elaborated.

Roles of plasma leptin and resistin in novel subgroups of type 2 diabetes driven by cluster analysis

Background

A novel classification has been introduced to promote precision medicine in diabetes. The current study aimed to investigate the relationship between leptin and resistin levels with novel refined subgroups in patients with type 2 diabetes mellitus (T2DM).

Methods

The k-means analysis was conducted to cluster 541 T2DM patients into the following four subgroups: mild obesity-related diabetes (MOD), severe insulin-deficient diabetes (SIDD), severe insulin-resistant diabetes (SIRD) and mild age-related diabetes (MARD). Individuals meeting the exclusion criteria were eliminated, the data for 285 patients were analyzed. Characteristics were determined using various clinical parameters. Both the leptin and resistin levels were determined using enzyme-linked immunosorbent assay.

Results

The highest levels of plasma leptin were in the MOD group with relatively lower levels in the SIDD and SIRD groups (P < 0.001). The SIRD group had a higher resistin concentration than the MARD group (P = 0.024) while no statistical significance in resistin levels was found between the SIDD and MOD groups. Logistic regression demonstrated that plasma resistin was associated with a higher risk of diabetic nephropathy (odds ratios (OR) = 2.255, P = 0.001). According to receiver operating characteristic (ROC) curves, the area under the curve (AUC) of resistin (0.748, 95% CI 0.610–0.887) was significantly greater than that of HOMA2-IR (0.447, 95% CI 0.280–0.614) (P < 0.05) for diabetic nephropathy in the SIRD group.

Conclusions

Leptin levels were different in four subgroups of T2DM and were highest in the MOD group. Resistin was elevated in the SIRD group and was closely related to diabetic nephropathy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-022-01623-z.

Analysis of an Indian diabetes prevention programme on association of adipokines and a hepatokine with incident diabetes

To study the association and possible predictive role of visfatin, resistin, fetuin-A and chemerin with incident type 2 diabetes (T2DM) among Asian Indians with prediabetes. Their association with insulin resistance, β-cell function, glycaemia and anthropometry were also studied. This is a nested case-control study of a large 2-year prospective prevention trial in persons at high risk of developing T2DM. Baseline HbA1c values between 6.0% (42 mmol/mol) and 6.2% (44 mmol/mol) were chosen for this analysis (n = 144). At follow-up, persons with incident T2DM (HbA1c ≥ 6.5%, 48 mmol/mol) were grouped as cases (n = 72) and those reverted to normoglycaemia, (HbA1c < 5.7% (39 mmol/mol) as controls (n = 72). Insulin resistance showed the strongest association with incident T2DM ((Odds Ratio (OR): 23.22 [95%CI 6.36-84.77]; p < 0.0001). Baseline visfatin (OR: 6.56 [95%CI 2.21-19.5]; p < 0.001) and fetuin-A (OR: 1.01 [95%CI (1.01-1.04)]; p < 0.0001) independently contributed to the conversion of prediabetes to T2DM. The contribution was significantly higher when their elevated levels coexisted (OR: 12.63 [95%CI 3.57-44.63]; p < 0.0001). The area under the curve was 0.77 ± SE 0.4 (95%CI 0.69-0.85) and 0.80 ± SE 0.04 (95%CI 0.73-0.88) for visfatin (median 17.7 ng/ml, sensitivity and specificity: 75%, p < 0.0001) and fetuin-A (mean 236.2 µg/ml, sensitivity: 71%, specificity: 75%, p < 0.0001) respectively. Higher baseline visfatin and fetuin-A concentrations are strongly associated with incident T2DM and are predictive of future diabetes.

Association of ANGPTL8 and Resistin With Diabetic Nephropathy in Type 2 Diabetes Mellitus

Background

Previous studies showed altered angiopoietin-like protein-8 (ANGPTL-8) and resistin circulating levels in type 2 diabetes mellitus (T2DM). Whether or not the alteration in ANGPTL-8 and resistin level can be a predictive maker for increased diabetic nephropathy risk remains unclear.

Aim

To Investigate the possible association of ANGPTL-8 and resistin with DN, and whether this association is affected by NAFLD status.

Methods

A total of 278 T2DM patients were enrolled. Serum levels of ANGPTL8, resistin, BMI, blood pressure, duration of diabetes, glycosylated hemoglobin (HbA1c), fasting blood glucose (FPG), hypersensitive C-reactive protein (hs-CRP), lipid profile, liver, and kidney function tests were assessed. The relationship between DN with ANGPTL8 and resistin was analyzed in the unadjusted and multiple-adjusted regression models.

Results

Serum levels of ANGPTL8 and resistin were significantly higher in DN compared with T2DM subjects without DN (respectively; P <0.001), especially in non-NAFLD populations. ANGPTL8 and resistin showed positive correlation with hs-CRP (respectively; P<0.01), and negative correlation with estimated GFR (eGFR) (respectively; P=<0.001) but no significant correlation to HOMA-IR(respectively; P>0.05). Analysis showed ANGPTL8 levels were positively associated with resistin but only in T2DM patients with DN(r=0.1867; P<0.05), and this significant correlation disappeared in T2DM patients without DN. After adjusting for confounding factors, both ANGPTL8(OR=2.095, 95%CI 1.253-3.502 P=0.005) and resistin (OR=2.499, 95%CI 1.484-4.208 P=0.001) were risk factors for DN. Data in non-NAFLD population increased the relationship between ANGPTL8 (OR=2.713, 95% CI 1.494-4.926 P=0.001), resistin (OR=4.248, 95% CI 2.260-7.987 P<0.001)and DN. The area under the curve (AUC) on receiver operating characteristic (ROC) analysis of the combination of ANGPTL8 and resistin was 0.703, and the specificity was 70.4%. These data were also increased in non-NAFLD population, as the AUC (95%CI) was 0.756, and the specificity was 91.2%.

Conclusion

This study highlights a close association between ANGPTL8, resistin and DN, especially in non-NAFLD populations. These results suggest that ANGPTL-8 and resistin may be risk predictors of DN.

Can serum resistin predict severity of acute pancreatitis?

OBJECTIVE

Acute pancreatitis (AP) is a common disorder with high mortality in severe cases. Several markers have been studied to predict development of severe AP (SAP) including serum resistin with conflicting results. This study aimed at assessing the role of baseline serum resistin levels in predicting SAP.

METHODS

This prospective study collected data from 130 AP patients from July 2017 to Nov 2018. Parameters measured included demographic profile, serum resistin at admission, severity scores, hospital stay, surgery, and mortality. Patients were divided into two groups, severe and non-severe AP. The two groups were compared for baseline characteristics, serum resistin levels, hospital stay, surgery and mortality.

RESULTS

Among 130 patients, 53 patients had SAP. SAP patients had higher BMI, baseline CRP, APACHE II and CTSI scores (p-value 0.045, <0.001, <0.001 and 0.001, respectively). Both groups had comparable serum resistin levels. Serum resistin levels were also not different for obese and non-obese patients (p-value = 0.62). On multivariate analysis, BMI and high APACHE II score and CRP levels were found to independently predict SAP.

CONCLUSION

We found that serum resistin is not a useful marker for predicting the severity of AP and does not correlate with increasing body weight.

Trelagliptin succinate: DPP-4 inhibitor to improve insulin resistance in adipocytes

Trelagliptin inhibits the enzyme dipeptidyl-4 (DPP-4) to treat type 2 diabetes and it may possess the potential to improve insulin resistance. However, the molecular mechanism is not known. In this study, the effect of trelagliptin succinate in improving insulin resistance was investigated. The differentiation system of 3T3-L1 mouse preadipocytes was used to determine the content of adipokines and the content of GLUT4 in the outer membrane. The expression of AKT, P-AKT, IRS-1 and P-IRS-1 in differentiated 3T3-L1 adipocytes was determined by western blotting. Our results demonstrated that trelagliptin succinate increased the expression of AKT, P-AKT, IRS-1 and P-IRS-1 in the PI-3K/AKT insulin signaling pathway. These events promote the trans-membrane function of GLUT4 and concomitant glucose intake in adipocytes. In addition, the secretion of free fatty acids and resistin were decreased. In conclusion, our study suggested that trelagliptin succinate improved insulin resistance in adipocytes via regulation of PI-3K/AKT/GLUT4 insulin signaling pathway.

A new research hot spot: The role of NLRP3 inflammasome activation, a key step in pyroptosis, in diabetes and diabetic complications

Pyroptosis is a form of cell death mediated by gasdermin D (GSDMD); it is characterised by NLRP3 inflammasome activation, caspase activation, cell membrane pore formation, and the release of interleukin-1β and interleukin-18. NLRP3 inflammasome activation plays a central role in pyroptosis. Recent research has suggested that NLRP3 inflammasome activation may be involved in the occurrence and development of diabetes mellitus and its associated complications. This finding provided the impetus for us to clarify the significance of pyroptosis in diabetes. In this review, we summarise the current understanding of the molecular mechanisms involved in pyroptosis, as well as recent advances in the role of NLRP3 inflammasome activation and pyroptosis in the development of diabetes and diabetic complications.

Relation of Circulating Resistin to Insulin Resistance in Type 2 Diabetes and Obesity: A Systematic Review and Meta-Analysis

Background: Resistin, a cysteine-rich polypeptide encoded by the RETN gene, which plays an important role in many mechanisms in rodent studies, including lipid metabolism, inflammation and insulin resistance. Nevertheless, the relationship between resistin and insulin resistance in humans is under debate. The present study was designed to clarify the correlation between resistin and insulin resistance. Methods: A systematic literature search was performed using PubMed, Embase and Cochrane Library until March 3, 2019 with the keywords "resistin" and "insulin resistance." Funnel plots and Egger's test were used to detect publication bias. A random-effects model was used to calculate the pooled effect size. Subgroup analysis and meta regression was performed to identify the sources of heterogeneity. Results: Fifteen studies were included in our systematic review. Among them, 10 studies with Pearson coefficients were used for meta-analysis. We found resistin levels were weakly correlated with insulin resistance in those with T2DM and obesity (r = 0.21, 95% CI: 0.06-0.35, I 2 = 59.7%, P = 0.003). Nevertheless, subgroup analysis suggested that circulating resistin levels were significantly positively correlated with insulin resistance in individuals with hyperresistinemia (≥14.8 ng/ml) (r = 0.52, 95% CI: 0.35-0.68, I 2 = 0.0%, P = 0.513). And there was no relationship between circulating resistin and insulin resistance in those with normal circulating resistin levels (<14.8 ng/ml) (r = 0.08, 95% CI: -0.01-0.18, I 2 = 0.0%, P = 0.455). Publication bias was insignificant (Egger's test P = 0.592). Conclusion: In T2DM and obese individuals, resistin levels were positively correlated with insulin resistance in those with hyperresistinemia, but not in those with normal circulating resistin levels.

New Insights into Adipokines as Potential Biomarkers for Type-2 Diabetes Mellitus

A large number of studies have been focused on investigating serum biomarkers associated with risk or diagnosis of type-2 diabetes mellitus. In the last decade, promising studies have shown that circulating levels of adipokines could be used as a relevant biomarker for diabetes mellitus progression as well as therapeutic future targets. Here, we discuss the possible use of recently described adipokines, including apelin, omentin-1, resistin, FGF-21, neuregulin-4 and visfatin, as early biomarkers for diabetes. In addition, we also include recent findings of other well known adipokines such as leptin and adiponectin. In conclusion, further studies are needed to clarify the pathophysiological significance and clinical value of these biological factors as potential biomarkers in type-2 diabetes and related dysfunctions.

Adipokine levels in overweight women with early-onset gestational diabetes mellitus

PURPOSE

The study of adipokines in overweight women with early-onset (diagnosed before 20 weeks) gestational diabetes mellitus (GDM) could help to understand the ethiopathological mechanisms of this disorder. Our aim was to assess adipokine levels in overweight pregnant women with early-onset GDM compared to patients with standard-onset (diagnosed at 24-28 weeks) GDM and to glucose-tolerant women at the same gestational ages.

METHODS

This nested case-control study included 133 overweight pregnant women: 33 with early-onset (diagnosed < 20 weeks) GDM; 40 with standard-onset (diagnosed ≥ 24 weeks) GDM and 60 glucose-tolerant (normal oral glucose tolerance tests < 20 and ≥ 24 weeks). Adiponectin, leptin, resistin, visfatin and ghrelin serum levels were measured by ELISA.

RESULTS

Adiponectin serum levels were significantly lower in early-onset GDM women than in standard-onset GDM patients or controls matched for gestational age. Leptin serum levels were significantly higher in women with early-onset GDM than in controls. Women with early-onset GDM had lower adiponectin/leptin ratio than those with standard-onset GDM. There were no significant differences in resistin, ghrelin and visfatin serum levels among the participants.

CONCLUSIONS

Our results suggest that, compared to overweight glucose-tolerant women and patients with standard-onset GDM, overweight women with early-onset GDM have unbalanced adipokine levels, suggesting that they have a more inflammatory profile.

Adipocytokines in Rheumatoid Arthritis: The Hidden Link between Inflammation and Cardiometabolic Comorbidities

Rheumatoid arthritis is a chronic autoimmune disease affecting typically synovial joints and leading to progressive articular damage, disability, and reduced quality of life. Despite better recent therapeutic strategies improving long-term outcomes, RA is associated with a high rate of comorbidities, infections, malignancies, and cardiovascular disease (CVD). Remarkably, some well-known pathogenic proinflammatory mediators in RA, such as interleukin-1β (IL-1β) and tumor necrosis factor (TNF), may play a pivotal role in the development of CVD. Interestingly, different preclinical and clinical studies have suggested that biologic agents commonly used to treat RA patients may be effective in improving CVD. In this context, the contribution of adipocytokines has been suggested. Adipocytokines are pleiotropic molecules, mainly released by white adipose tissue and immune cells. Adipocytokines modulate the function of different tissues and cells, and in addition to energy homeostasis and metabolism, amplify inflammation, immune response, and tissue damage. Adipocytokines may contribute to the proinflammatory state in RA patients and development of bone damage. Furthermore, they could be associated with the occurrence of CVD. In this study, we reviewed available evidence about adipocytokines in RA, because of their involvement in disease activity, associated CVD, and possible biomarkers of prognosis and treatment outcome and because of their potential as a possible new therapeutic target.

Obese subcutaneous adipose tissue impairs human myogenesis, particularly in old skeletal muscle, via resistin-mediated activation of NFκB

Adiposity and adipokines are implicated in the loss of skeletal muscle mass with age and in several chronic disease states. The aim of this study was to determine the effects of human obese and lean subcutaneous adipose tissue secretome on myogenesis and metabolism in skeletal muscle cells derived from both young (18-30 yr) and elderly (>65 yr) individuals. Obese subcutaneous adipose tissue secretome impaired the myogenesis of old myoblasts but not young myoblasts. Resistin was prolifically secreted by obese subcutaneous adipose tissue and impaired myotube thickness and nuclear fusion by activation of the classical NFκB pathway. Depletion of resistin from obese adipose tissue secretome restored myogenesis. Inhibition of the classical NFκB pathway protected myoblasts from the detrimental effect of resistin on myogenesis. Resistin also promoted intramyocellular lipid accumulation in myotubes and altered myotube metabolism by enhancing fatty acid oxidation and increasing myotube respiration and ATP production. In conclusion, resistin derived from human obese subcutaneous adipose tissue impairs myogenesis of human skeletal muscle, particularly older muscle, and alters muscle metabolism in developing myotubes. These findings may have important implications for the maintenance of muscle mass in older people with chronic inflammatory conditions, or older people who are obese or overweight.

The role of adipokines in skeletal muscle inflammation and insulin sensitivity

Background

There is currently an unmet clinical need to develop better pharmacological treatments to improve glucose handling in Type II Diabetes patients with obesity. To this end, determining the effect of obesity-associated adipokines on skeletal muscle insulin sensitivity has emerged as an important area of drug discovery research. This review draws together the data on the functional role of adipokines on skeletal muscle insulin signalling, highlights several understudied novel adipokines and provides a perspective on the direction of future research.

Main body

The adipokines leptin, resistin, visfatin and adiponectin have all been shown to affect skeletal muscle insulin sensitivity by impacting on the activity of components within insulin signalling pathways, affecting GLUT4 translocation and modulating insulin-mediated skeletal muscle glucose uptake. Furthermore, proteomic analysis of the adipose tissue secretome has recently identified several novel adipokines including vaspin, chemerin and pref-1 that are associated with obesity and insulin resistance in humans and functionally impact on insulin signalling pathways. However, predominantly, these functional findings are the result of studies in rodents, with in vitro studies utilising either rat L6 or murine C2C12 myoblasts and/or myotubes. Despite the methodology to isolate and culture human myoblasts and to differentiate them into myotubes being established, the use of human muscle in vitro models for the functional validation of adipokines on skeletal muscle insulin sensitivity is limited.

Conclusion

Understanding the mechanism of action and function of adipokines in mediating insulin sensitivity in skeletal muscle may lead to the development of novel therapeutics for patients with type 2 diabetes. However, to date, studies conducted in human skeletal muscle cells and tissues are limited. Such human in vitro studies should be prioritised in order to reduce the risk of candidate drugs failing in the clinic due to the assumption that rodent skeletal muscle target validation studies will to translate to human.

Benefits of Nut Consumption on Insulin Resistance and Cardiovascular Risk Factors: Multiple Potential Mechanisms of Actions

Epidemiological and clinical studies have indicated that nut consumption could be a healthy dietary strategy to prevent and treat type 2 diabetes (T2DM) and related cardiovascular disease (CVD). The objective of this review is to examine the potential mechanisms of action of nuts addressing effects on glycemic control, weight management, energy balance, appetite, gut microbiota modification, lipid metabolism, oxidative stress, inflammation, endothelial function and blood pressure with a focus on data from both animal and human studies. The favourable effects of nuts could be explained by the unique nutrient composition and bioactive compounds in nuts. Unsaturated fatty acids (monounsaturated fatty acids and polyunsaturated fatty acids) present in nuts may play a role in glucose control and appetite suppression. Fiber and polyphenols in nuts may also have an anti-diabetic effect by altering gut microbiota. Nuts lower serum cholesterol by reduced cholesterol absorption, inhibition of HMG-CoA reductase and increased bile acid production by stimulation of 7-α hydroxylase. Arginine and magnesium improve inflammation, oxidative stress, endothelial function and blood pressure. In conclusion, nuts contain compounds that favourably influence glucose homeostasis, weight control and vascular health. Further investigations are required to identify the most important mechanisms by which nuts decrease the risk of T2DM and CVD.

Maternal and fetal lipid metabolism under normal and gestational diabetic conditions

Maternal lipids are strong determinants of fetal fat mass. Here we review the overall lipid metabolism in normal and gestational diabetes mellitus (GDM) pregnancies. During early pregnancy, the increase in maternal fat depots is facilitated by insulin, followed by increased adipose tissue breakdown and subsequent hypertriglyceridemia, mainly as a result of insulin resistance (IR) and estrogen effects. The response to diabetes is variable as a result of greater IR but decreased estrogen levels. The vast majority of fatty acids (FAs) in the maternal circulation are esterified and associated with lipoproteins. These are taken up by the placenta and hydrolyzed by lipases. The released FAs enter various metabolic routes and are released into fetal circulation. Although these determinants are modified in maternal GDM, the fetus does not seem to receive more FAs than in non-GDM pregnancies. Long-chain polyunsaturated FAs are essential for fetal development and are obtained from the mother. Mitochondrial FA oxidation occurs in fetal tissue and in placenta and contributes to energy production. Fetal fat accretion during the last weeks of gestation occurs very rapidly and is sustained not only by FAs crossing the placenta, but also by fetal lipogenesis. Fetal hyperinsulinemia in GDM mothers promotes excess accretion of adipose tissue, which gives rise to altered adipocytokine profiles. Fetal lipoproteins are low at birth, but the GDM effects are unclear. The increase in body fat in neonates of GDM women is a risk factor for obesity in early childhood and later life.

Beneficial Effects of n-3 Fatty Acids on Cardiometabolic and Inflammatory Markers in Type 2 Diabetes Mellitus: A Clinical Trial

OBJECTIVE

To determine the effect of supplementation with n-3 polyunsaturated fatty acids (PUFAs) on circulatory resistin and monocyte chemoattractant protein 1 (MCP-1) levels in type 2 diabetes mellitus (T2DM) patients.

SUBJECTS AND METHODS

This was a 10-week, placebo-controlled, double-blind, randomized trial of n-3 PUFAs (2,700 mg/day) versus placebo (soft gels containing 900 mg of edible paraffin). Forty-four T2DM patients were supplemented with n-3 PUFAs and another 44 patients received placebo (3 patients discontinued the trial). Serum resistin, MCP-1, and the lipid profile were measured before and after supplementation. The adiponectin-resistin index (1 + log10 [resistin] - log10 [adiponectin]) and atherogenic index (log10 triglyceride/high-density lipoprotein cholesterol) of plasma (an indicator of cardiovascular complications) were assessed. The independent Student t test was used to assess the differences between the supplement and placebo groups and the paired t test to analyze the before/after changes.

RESULTS

In this study, n-3 PUFAs reduced serum MCP-1 levels (from 260.5 to 230.5 pg/mL; p = 0.002), but they remained unchanged in the placebo group. n-3 PUFAs could not decrease serum resistin levels. The adiponectin-resistin index was significantly reduced after supplementation with n-3 PUFAs when compared to the placebo. The atherogenic index was also significantly improved after supplementation with n-3 PUFAs (from 1.459 to 1.412; p = 0.006).

CONCLUSIONS

The MCP-1 levels and lipid profile were improved after supplementation with n-3 PUFAs, but resistin serum levels were not changed. Hence, the anti-inflammatory effects of n-3 PUFAs might be mediated by targeting MCP-1.

Maternal vitamin D deficiency during pregnancy affects expression of adipogenic-regulating genes peroxisome proliferator-activated receptor gamma (PPARγ) and vitamin D receptor (VDR) in lean male mice offspring

PURPOSE

Maternal vitamin D deficiency during pregnancy is a widespread issue that may have long-lasting consequences on offspring adiposity. We sought to determine how maternal vitamin D deficiency during the perinatal period would affect offspring adipose tissue development and gene expression.

METHODS

Female C57BL/6 J mice were fed either a vitamin D deficient (VDD) or control diet from 4 weeks before pregnancy (periconception) until 7 days postparturition. Male offspring were weighed and euthanized at 75 days of age (early adult period), at which point serum was collected for biochemical analyses, and perigonadal and subcutaneous white adipose tissue (PGAT and SQAT, respectively) were excised, weighed, then flash-frozen for later histology and analyses of adipogenic gene expression.

RESULTS

All adult male offspring were nonobese; there were no significant differences in body weight, adipose pad weight, or adipocyte size. However, VDD-exposed offspring had greater expression of the adipogenic-regulating genes peroxisome proliferator-activated receptor gamma (Pparg) and vitamin D receptor (Vdr).

CONCLUSIONS

This study suggests that exposure to vitamin D deficiency during the perinatal period can directly affect genes involved in the development of adipose tissue in nonobese offspring. These novel findings invite further investigation into the mechanisms by which maternal vitamin D status during pregnancy affects adipose development and metabolic health of offspring.

Increased circulating resistin is associated with insulin resistance, oxidative stress and platelet activation in type 2 diabetes mellitus

Resistin is an adipokine that promotes inflammation and insulin resistance by targeting several cells including platelets. We hypothesised that in type 2 diabetes (T2DM), resistin may foster in vivo oxidative stress, thromboxane-dependent platelet activation and platelet-derived inflammatory proteins release, key determinants of atherothrombosis. A cross-sectional comparison of circulating resistin, sCD40L, as a marker of platelet-mediated inflammation, asymmetric dimethylarginine (ADMA), endothelial dysfunction marker, Dickkopf (DKK)-1, reflecting the inflammatory interaction between platelets and endothelial cells, and urinary 8-iso-PGF_2α and 11-dehydro-TxB₂, reflecting in vivo lipid peroxidation and platelet activation, respectively, was performed between 79 T2DM patients and 30 healthy subjects. Furthermore, we investigated the effects of the α-glucosidase inhibitor acarbose and the PPARγ agonist rosiglitazone, targeting hyperglycaemia or insulin resistance, versus placebo, in 28 and 18 T2DM subjects, respectively. Age- and gender-adjusted serum resistin levels were significantly higher in patients than in controls. HOMA (β=0.266, p=0.017) and 11-dehydro-TXB₂ (β=0.354, p=0.002) independently predicted resistin levels. A 20-week treatment with acarbose was associated with significant reductions (p=0.001) in serum resistin, DKK-1, urinary 11-dehydro-TXB₂ and 8-iso-PGF_2α with direct correlations between the change in serum resistin and in other variables. A 24-week rosiglitazone treatment on top of metformin was associated with significant decreases in resistin, DKK-1, 11-dehydro-TXB₂ and 8-iso-PGF_2α, in parallel with HOMA decrease. In conclusion, resistin, antagonising insulin action in part through PPARγ activation, may favour insulin resistance and enhance oxidative stress, endothelial dysfunction and platelet activation. The adipokine-platelet interactions may be involved in platelet insulin resistance and their consequent pro-aggregatory phenotype in this setting.

Circulating Chemerin Is Associated With Carotid Plaque Instability, Whereas Resistin Is Related to Cerebrovascular Symptomatology

OBJECTIVE

The rupture of unstable carotid atherosclerotic plaques is one of the main causes of cerebrovascular ischemic events. There is need for circulating markers that can predict plaque instability and risk of stroke. Proinflammatory chemerin, leptin, and resistin, along with anti-inflammatory adiponectin, are adipokines with direct influence on vascular function. We investigated the association of circulating adipokines with carotid plaque instability and cerebrovascular symptomatology.

APPROACH AND RESULTS

Neurologically symptomatic and asymptomatic patients (n=165) scheduled for carotid endarterectomy were recruited. Fasting blood samples were collected preoperatively; adiponectin and leptin levels were determined by radioimmunoassay; and chemerin and resistin levels were measured by enzyme-linked immunosorbent assays. The instability of plaque specimens was assessed using gold-standard histological classifications. Chemerin was significantly associated with plaque instability. The fully adjusted model, accounting for age, sex, body mass index, high-sensitivity C-reactive protein, type 2 diabetes mellitus, and circulating adiponectin, leptin, and resistin, yielded an odds ratio of 0.991 (95% confidence interval 0.985-0.998) for plaque instability per unit increase in chemerin. High leptin levels were significantly associated with presence of specific features of plaque instability. In subjects with type 2 diabetes mellitus, resistin levels were significantly elevated in symptomatic when compared with asymptomatic subjects (P=0.001) and increased the risk of cerebrovascular symptomatology (adjusted odds ratio 1.264, 95% confidence interval 1.004-1.594).

CONCLUSIONS

Low chemerin and high resistin levels were associated with carotid disease severity, suggesting that these adipokines may act as potential markers for plaque instability and stroke risk. Future studies are needed to assess causation between circulating adipokines and plaque instability.

Biomarkers of Metabolic Syndrome: Biochemical Background and Clinical Significance

Biomarkers of the metabolic syndrome are divided into four subgroups. Although dividing them in groups has some limitations, it can be used to draw some conclusions. In a first part, the dyslipidemias and markers of oxidative stress are discussed, while inflammatory markers and cardiometabolic biomarkers are reviewed in a second part. For most of them, the biochemical background and clinical significance are discussed, although here also a well-cut separation cannot always be made. Altered levels cannot always be claimed as the cause, risk, or consequence of the syndrome. Several factors are interrelated to each other and act in a concerted, antagonistic, synergistic, or modulating way. Most important conclusions are summarized at the end of every reviewed subgroup. Genetic biomarkers or influences of various food components on concentration levels are not included in this review article.

The effects of serum from prostate cancer patients with elevated body mass index on prostate cancer cells in vitro

We examined whether serum from obese, compared to non-obese, PCa (prostate cancer) patients creates a growth-enhancing tumor micro-environment in vitro. Serum from 80 subjects was divided into four groups: normal weight men with and without PCa and overweight/obese men with and without PCa. Cell proliferation, migration, and invasion were measured in LNCaP, and PC3 cells treated with patient serum were obtained from the above groups. The results reveal that proliferation of LNCaP cells was significantly (P = 0.05) greater with serum from non-obese (mean = 1.26 ± 0.20) compared to that from obese patients (mean = 1.16 ± 0.19). Serum from obese PCa patients compared to non-obese PCa patients induced significantly greater amounts of cell migration (P < 0.01) in PC3 cells. Serum from obese patients induced significantly (P < 0.01) lower amounts of cell invasion (mean = 8.2 ± 4.5) compared to non-obese patients (mean = 18.1 ± 5.0) when treated on PC3 cells. Serum TNF-α (tumor necrosis factor alpha) levels correlated with LNCaP cell proliferation in vitro in non-obese PCa (P < 0.01) and non-obese control groups (P = 0.05). All statistical calculations controlled for age, since the PCa patient groups were significantly older than the control groups (P < 0.01). In conclusion, serum from obese PCa patients induced greater PCa cell migration and lower cell proliferation and invasion in vitro.

Resistin - 420 C/G polymorphism and serum resistin level in Iranian patients with gestational diabetes mellitus

Background

Resistin is a circulating adipokine with insulin-antagonizing effects. The aim of this study was to investigate the relationship between the single nucleotide polymorphism (SNP) -420C > G in the resistin gene with serum resistin levels, insulin resistance, and risk of gestational diabetes (GDM) in Iranian population.

Method

75 GDM patients and 70 healthy pregnant women were enrolled in this study. Genotyping for SNP- 420C > G in the resistin gene was performed by the polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) method. Serum resistin and insulin were measured by immunoassay. Blood glucose levels and lipid profile were measured by enzymatic methods. Homeostasis model of assessment for insulin resistance (HOMA-IR) were calculated.

Result

GG genotype and G allele of SNP-420C > G were more frequent in GDM patients compared to non-GDM subjects. Serum resistin level was similar in GDM and non-GDM patients. The serum levels of resistin in GDM and non-GDM women with GG genotype were similar to those with GC + CC genotype. Multivariate logistic regression analysis after adjusting for confounding factors showed a higher susceptibility to GDM in patients with GG genotype compared to subjects with GG + GT genotype (odds ratio = 4.59, 95% CI; 1.96-10.71, p = 0.00). Serum resistin level was correlated with serum triglyceride, total and low density lipoprotein (LDL) cholesterol (p < 0.05) in GDM patients. No significant association was found between serum resistin, insulin resistance, and SNP-420C > G.

Conclusion

The SNP-420C/G of resistin gene is associated with genetic susceptibility to GDM in our population. Further studies are necessary to confirm the role of this polymorphism in pathogenesis of GDM and to explore potential mechanisms by which it modulates susceptibility to GDM.

Mechanisms of enhanced insulin secretion and sensitivity with n-3 unsaturated fatty acids

The widespread acceptance that increased dietary n-3 polyunsaturated fatty acids (PUFAs), especially α-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), improve health is based on extensive studies in animals, isolated cells and humans. Visceral adiposity is part of the metabolic syndrome, together with insulin resistance, dyslipidemia, hypertension and inflammation. Alleviation of metabolic syndrome requires normalization of insulin release and responses. This review assesses our current knowledge of the mechanisms that allow n-3 PUFAs to improve insulin secretion and sensitivity. EPA has been more extensively studied than either ALA or DHA. The complex actions of EPA include increased G-protein-receptor-mediated release of glucagon-like peptide 1 (GLP-1) from enteroendocrine L-cells in the intestine, up-regulation of the apelin pathway and down-regulation of other control pathways to promote insulin secretion by the pancreatic β-cells, together with suppression of inflammatory responses to adipokines, inhibition of peroxisome proliferator-activated receptor α actions and prevention of decreased insulin-like growth factor-1 secretion to improve peripheral insulin responses. The receptors involved and the mechanisms of action probably differ for ALA and DHA, with antiobesity effects predominating for ALA and anti-inflammatory effects for DHA. Modifying both GLP-1 release and the actions of adipokines by n-3 PUFAs could lead to additive improvements in both insulin secretion and sensitivity.

Genetics and epigenetics of aging and longevity

Evolutionary theories of aging predict the existence of certain genes that provide selective advantage early in life with adverse effect on lifespan later in life (antagonistic pleiotropy theory) or longevity insurance genes (disposable soma theory). Indeed, the study of human and animal genetics is gradually identifying new genes that increase lifespan when overexpressed or mutated: gerontogenes. Furthermore, genetic and epigenetic mechanisms are being identified that have a positive effect on longevity. The gerontogenes are classified as lifespan regulators, mediators, effectors, housekeeping genes, genes involved in mitochondrial function, and genes regulating cellular senescence and apoptosis. In this review we demonstrate that the majority of the genes as well as genetic and epigenetic mechanisms that are involved in regulation of longevity are highly interconnected and related to stress response.

Adipokines, metabolic syndrome and rheumatic diseases

The metabolic syndrome (MetS) is a cluster of cardiometabolic disorders that result from the increasing prevalence of obesity. The major components of MetS include insulin resistance, central obesity, dyslipidemia, and hypertension. MetS identifies the central obesity with increased risk for cardiovascular diseases (CVDs) and type-2 diabetes mellitus (T2DM). Patients with rheumatic diseases, such as rheumatoid arthritis, osteoarthritis, systemic lupus erythematosus, and ankylosing spondylitis, have increased prevalence of CVDs. Moreover, CVD risk is increased when obesity is present in these patients. However, traditional cardiovascular risk factors do not completely explain the enhanced cardiovascular risk in this population. Thus, MetS and the altered secretion patterns of proinflammatory adipokines present in obesity could be the link between CVDs and rheumatic diseases. Furthermore, adipokines have been linked to the pathogenesis of MetS and its comorbidities through their effects on vascular function and inflammation. In the present paper, we review recent evidence of the role played by adipokines in the modulation of MetS in the general population, and in patients with rheumatic diseases.

Atorvastatin treatment modulates the interaction between leptin and adiponectin, and the clinical parameters in patients with type II diabetes

The aim of this study was to examine the effect of atorvastatin treatment on levels of leptin, adiponectin and insulin resistance, and their correlation with clinical parameters, in patients with type II diabetes. Patients with diabetes (n=394) were divided into two groups, comprising 161 patients who received 20 mg/day atorvastatin (statin group), and 233 patients who did not receive statins (statin-free group). The results showed that atorvastatin treatment of patients with diabetes was not associated with changes in leptin, adiponectin, the leptin/adiponectin (L/A) ratio or homeostasis model assessment-insulin resistance (HOMA-IR). However, low-density lipoprotein cholesterol (LDL-C), triglycerides (TG) and total cholesterol (Tchol) were positively correlated with leptin and L/A ratio in the statin group only (P<0.05). By contrast, high-density lipoprotein cholesterol (HDL-C) showed a significant positive correlation with adiponectin in the statin and statin-free groups (P<0.05). Additionally, a positive correlation was found between HOMA-IR and glycated hemoglobin (HbA1c), and TG, in both groups, whereas Tchol was positively correlated with HOMA-IR in the statin group only (P<0.05). When multivariate analysis was performed with HOMA-IR as the dependent variable, and with adjustment for age, body mass index (BMI) and waist circumference, HbA1c was found to be a significant predictor of HOMA-IR or insulin resistance. In conclusion, atorvastatin treatment may have several effects on the interaction between leptin and adiponectin, and on clinical parameters in patients with type II diabetes.

Ellagic acid improves hepatic steatosis and serum lipid composition through reduction of serum resistin levels and transcriptional activation of hepatic ppara in obese, diabetic KK-A(y) mice

Ellagic acid (EA) is a polyphenol found in a wide variety of plant foods that not only exhibits free radical-scavenging activity, but also confers protective effects against liver injury. Previously, we reported that pomegranate fruit extract (PFE) had an inhibitory effect on resistin secretion from differentiated murine 3T3-L1 adipocytes and identified EA contained in PFE as a potent suppressor of resistin secretion. Resistin, an adipocytokine, is considered the link between obesity and type 2 diabetes. In this study, we explored whether EA supplementation reduces serum resistin and improves hepatic steatosis and serum lipid profile by using KK-A(y) mice fed high-fat diet as a model for obese type 2 diabetes. We found that EA supplementation improved serum lipid profile and hepatic steatosis, and reduced serum resistin levels without altering mRNA expression levels in adipose tissue. Moreover, EA supplementation upregulated mRNA expression of apoa1, ldlr, cpt1a, and ppara genes in the liver. In conclusion, our findings indicate that EA is a potent suppressor of resistin secretion in vivo and a transcriptional activator of ppara in the liver, suggesting a possibility for improving obesity-induced dyslipidemia and hepatic steatosis in KK-A(y) mice.

Assessment of Cardiovascular Risk Factors Among University Students: The Gender Factor

Background

Evidence indicates that the pathophysiological process of cardiovascular (CV) disease begins at early age, though the manifestations of the disease do not appear until middle age adulthood. Risk factors for CV disease, particularly lipoprotein profiles, are affected by physiological abnormalities, and lifestyle related issues. To evaluate prevalence of CV diseases risk factors among university students and to investigate relation between number of risk factors and body anthropometric, hematological and biochemical indices parameters.

Methods

In this cross sectional study, 348 students were randomly recruited. Blood glucose, cholesterol profile (total, HDL, and LDL cholesterol), and triglyceride were measured using standard protocols. Physical activity (PA) level was assessed using the short-form Arabic version of the International Physical Activity Questionnaires (IPAQ).

Results

The most commonly encountered CV disease risk factor was low levels of HDL-C, followed by physical inactivity, high levels TG, and obese BMI. When stratified by gender, females were less likely to have low HDL-C, and high TG, whereas, males were more likely to have overweight or obese BMI (P < 0.001). About 49% of the participants had at least one CV disease risk factor, where as the prevalence of having one, two and three or more CV disease risk factors were 35.7%, 9.3% and 4%, respectively. Additionally, the number of CV disease risk factors showed strong positive correlation with increases in body fat and bone percentages, glucose, total cholesterol, TG, LDL-C, BMI, and WHR (range of R²: 0.17 to 0.603). On the other hand, physical activity, percentages of body water and muscle, HDL-C showed inverse strong correlation with cardiovascular risk factors (range of R²: -0.239 to -0.412).

Conclusions

Results indicate the high prevalence of CV disease risk factors among university students, and stress the need for early intervention programs to counteract these risks.

Resistin: functional roles and therapeutic considerations for cardiovascular disease

Resistin, originally described as an adipocyte-specific hormone, has been suggested to be an important link between obesity, insulin resistance and diabetes. Although its expression was initially defined in adipocytes, significant levels of resistin expression in humans are mainly found in mononuclear leukocytes, macrophages, spleen and bone marrow cells. Increasing evidence indicates that resistin plays important regulatory roles apart from its role in insulin resistance and diabetes in a variety of biological processes: atherosclerosis and cardiovascular disease (CVD), non-alcoholic fatty liver disease, autoimmune disease, malignancy, asthma, inflammatory bowel disease and chronic kidney disease. As CVD accounts for a significant amount of morbidity and mortality in patients with diabetes and without diabetes, it is important to understand the role that adipokines such as resistin play in the cardiovascular system. Evidence suggests that resistin is involved in pathological processes leading to CVD including inflammation, endothelial dysfunction, thrombosis, angiogenesis and smooth muscle cell dysfunction. The modes of action and signalling pathways whereby resistin interacts with its target cells are beginning to be understood. In this review, the current knowledge about the functions and pathophysiological implications of resistin in CVD development is summarized; clinical translations, therapeutic considerations and future directions in the field of resistin research are discussed.

LINKED ARTICLES

This article is part of a themed section on Fat and Vascular Responsiveness. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.165.issue-3.

Resistin: functional roles and therapeutic considerations for cardiovascular disease

Resistin, originally described as an adipocyte-specific hormone, has been suggested to be an important link between obesity, insulin resistance and diabetes. Although its expression was initially defined in adipocytes, significant levels of resistin expression in humans are mainly found in mononuclear leukocytes, macrophages, spleen and bone marrow cells. Increasing evidence indicates that resistin plays important regulatory roles apart from its role in insulin resistance and diabetes in a variety of biological processes: atherosclerosis and cardiovascular disease (CVD), non-alcoholic fatty liver disease, autoimmune disease, malignancy, asthma, inflammatory bowel disease and chronic kidney disease. As CVD accounts for a significant amount of morbidity and mortality in patients with diabetes and without diabetes, it is important to understand the role that adipokines such as resistin play in the cardiovascular system. Evidence suggests that resistin is involved in pathological processes leading to CVD including inflammation, endothelial dysfunction, thrombosis, angiogenesis and smooth muscle cell dysfunction. The modes of action and signalling pathways whereby resistin interacts with its target cells are beginning to be understood. In this review, the current knowledge about the functions and pathophysiological implications of resistin in CVD development is summarized; clinical translations, therapeutic considerations and future directions in the field of resistin research are discussed.

LINKED ARTICLES

This article is part of a themed section on Fat and Vascular Responsiveness. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.165.issue-3.

Visceral fat mass is always, but adipokines (adiponectin and resistin) are diversely associated with insulin resistance in Chinese type 2 diabetic and normoglycemic subjects

AIMS

The present study investigated alteration of abdominal visceral fat mass (VFM) and its relationship to adipokines and insulin resistance (IR) in obese and non-obese type 2 diabetes and normoglycemic subjects.

METHODS

Twenty-two diabetic patients and 37 normoglycemic controls were subgrouped into obese and non-obese according to their BMI. VFM was quantified by computed tomography. Plasma adiponectin and resistin, two adipokines exert contrary effects on insulin sensitivity were measured. Insulin sensitivity was evaluated by an established HOMA model.

RESULTS

Obese subjects showed remarkably expanded VFM, while non-obese diabetes obtained more abundant VFM than non-obese controls (104 ± 50 cm(2)vs. 77 ± 26 cm(2), P<0.05). Plasma adiponectin was only significantly decreased in obese diabetes. Plasma resistin was increased in diabetes, but compared between obese and non-obese subjects. Diabetic patients and obese controls were significantly insulin resistant. HOMA-IR index positively correlated to VFM in both groups (r=0.563, P=0.011 for diabetes and r=0.671, P=0.000 for controls). In diabetes but not controls, plasma adiponectin negatively related to VFM (r=-0.687, P=0.000) and HOMA-IR index (r=-0.659, P=0.002), while resistin had no relation to IR and VFM in both groups.

CONCLUSIONS

Increased VFM may lead to IR by mechanisms beyond adipokines in Chinese type 2 diabetic and normoglycemic subjects.

The clinical and nonclinical values of nonexercise estimation of cardiovascular endurance in young asymptomatic individuals

Exercise testing is associated with barriers prevent using cardiovascular (CV) endurance (CVE) measure frequently. A recent nonexercise model (NM) is alleged to estimate CVE without exercise. This study examined CVE relationships, using the NM model, with measures of obesity, physical fitness (PF), blood glucose and lipid, and circulation in 188 asymptomatic young (18–40 years) adults. Estimated CVE correlated favorably with measures of PF (r = 0.4 − 0.5) including handgrip strength, distance in 6 munities walking test, and shoulder press, and leg extension strengths, obesity (r = 0.2 − 0.7) including % body fat, body water content, fat mass, muscle mass, BMI, waist and hip circumferences and waist/hip ratio, and circulation (r = 0.2 − 0.3) including blood pressures, blood flow, vascular resistance, and blood (r = 0.2 − 0.5) profile including glucose, total cholesterol, LDL-C, HDL-C, and triglycerides. Additionally, differences (P < 0.05) in examined measures were found between the high, average, and low estimated CVE groups. Obviously the majority of these measures are CV disease risk factors and metabolic syndrome components. These results enhance the NM scientific value, and thus, can be further used in clinical and nonclinical settings.

Interactions between Serum Adipokines and Osteocalcin in Older Patients with Hip Fracture

Introduction. Experiments on genetically modified animals have discovered a complex cross-regulation between adipokines (leptin, adiponectin) and osteocalcin. The relationships between these molecules in human osteoporosis are still unclear. We evaluated the hypothesis of a bidirectional link between adipokines and osteocalcin. Materials and Methods. In a cross-sectional study of 294 older patients with osteoporotic hip fracture, we estimated serum concentrations of leptin, adiponectin, resistin, osteocalcin, parameters of mineral metabolism, and renal function. Results. After adjustment for multiple potential confounders, serum osteocalcin concentration was inversely associated with resistin and positively with leptin, leptin/resistin ratio, and adiponectin/resistin ratio. In multivariate regression models, osteocalcin was an independent predictor of serum leptin, resistin, leptin/resistin, and adiponectin/resistin ratios. Conclusions. Our data support the bidirectional regulation between osteocalcin and adipokines, but contrary to the genetically modified animal models, in older subjects with osteoporotic hip fracture, serum osteocalcin is positively associated with leptin and inversely with resistin.

Systemic resistin is increased in type 2 diabetic patients treated with loop diuretics

Increased serum resistin was found in rodent models of obesity and insulin resistance, whereas contradictory results have been obtained in human studies. In humans, resistin is primarily released by monocytes/macrophages, suggesting that soluble levels may be associated with macrophage activation. Here, systemic and monocyte-released resistin levels were found to be similar in type 2 diabetic (T2D) patients, overweight controls and normal-weight controls. When adjusted for body mass index and age, serum resistin modestly correlated with gamma-glutamyltransferase levels, fasting glucose and interleukin-6. Systemic resistin was marginally increased in T2D patients treated with beta-blockers or urate-lowering drugs and was considerably higher in patients treated with loop diuretics. Monocyte-released resistin was even reduced by the loop diuretic furosemide, excluding the possibility that this drug may directly stimulate resistin synthesis. In summary, the current data indicate that changes accompanying renal dysfunction but not obesity or type 2 diabetes are associated with increased serum resistin.

Lipodystrophy and insulin resistance in combination antiretroviral treated HIV-1-infected patients: implication of resistin

BACKGROUND

Little information is available with respect to the involvement of resistin in lipodystrophy and metabolic disturbances in HIV-1-infected patients treated with combination antiretroviral therapy (cART). We determined whether the resistin (rest) -420C>G single-nucleotide polymorphism and plasma resistin are associated with the development of lipodystrophy and metabolic disturbances in HIV-1-infected patients treated with cART.

METHODS

The study group comprised 299 HIV-1-infected patients treated with a stable cART for at least 1 year (143 with lipodystrophy and 156 without) and 175 uninfected controls. Anthropometric, clinical, and metabolic variables were determined. Homeostasis model assessment for insulin resistance was used to evaluate insulin resistance. Plasma resistin levels were determined by enzyme-linked immunosorbent assay. The rest -420C>G was assessed using restriction fragment length polymorphism. Student t test, 1-way and 2-way analysis of variance, χ2 test, and Pearson and Spearman correlations were performed for statistical analysis.

RESULTS

Genotypes containing the rest -420G variant allele were significantly more common in HIV-1-infected patients without lipodystrophy compared with those with lipodystrophy (P = 0.037). Infected patients had significantly greater plasma resistin levels than uninfected controls (P < 0.001). Among infected patients, plasma resistin levels were significantly lower in patients with lipodystrophy with respect to those without (P = 0.034). In infected patients, plasma resistin levels had a significant positive correlation with insulin and homeostasis model assessment for insulin resistance: P < 0.001 and P = 0.002 in the lipodystrophy subset and P = 0.002 and P = 0.03 in the nonlipodystrophy subset, respectively.

CONCLUSIONS

In our cohort of white Spaniards, the rest -420C>G single-nucleotide polymorphism may be associated with cART-related lipodystrophy. Plasma resistin correlates with insulin resistance in infected patients with and without lipodystrophy.