More than a simple storage organ: adipose tissue as a source of adipokines involved in cardiovascular disease

Effects of curcumin/turmeric supplementation on obesity indices and adipokines in adults: A grade-assessed systematic review and dose-response meta-analysis of randomized controlled trials

In the present study, we explored the effect of curcumin/turmeric supplementation on anthropometric indices of obesity, leptin, and adiponectin. We searched PubMed, Scopus, Web of Science, Cochrane Library, and Google Scholar up to August 2022. Randomized clinical trials (RCTs) investigating the impact of curcumin/turmeric on obesity indices and adipokines were included. We applied the Cochrane quality assessment tool to evaluate the risk of bias. The registration number is CRD42022350946. Sixty eligible RCTs, with a total sample size of 3691 individuals were included for quantitative analysis. We found that supplementation with curcumin/turmeric significantly reduced body weight (WMD: -0.82 kg, 95% CI: -1.30, -0.35; p = 0.001), body mass index (WMD: -0.30 kg/m² , 95% CI: -0.53, -0.06, p = 0.013), waist circumference (WMD: -1.31 cm, 95% CI: -1.94, -0.69, p < 0.001), body fat percentage (WMD: -0.88%, 95% CI: -1.51, -0.25, p = 0.007), leptin (WMD = -4.46 ng/mL; 95% CI: -6.70, -2.21, p < 0.001), and increased adiponectin (WMD = 2.48 μg/mL; 95% CI: 1.34, 3.62, p < 0.001). Overall, our study shows that supplementation with curcumin/turmeric significantly improves anthropometric indices of obesity and adiposity-related adipokines (leptin and adiponectin). However, due to high between-studies heterogeneity, we should interpret the results with caution.

Understanding the effect of obesity on papillary thyroid cancer: is there a need for tailored diagnostic and therapeutic management?

INTRODUCTION

Several studies have focused on the relationship between obesity and differentiated thyroid carcinoma (DTC), particularly papillary histotype (PTC). However, the association of obesity with both incidence and aggressiveness of PTC is still incompletely understood.

AREAS COVERED

We reviewed the mechanisms underlying the cross talk between obesity and thyroid carcinomas and described the most recent evidence evaluating the effect of obesity on the development of PTC, as well as the impact of excessive body weight on the clinicopathologic features and outcome of this type of cancer.

EXPERT OPINION

Available evidence suggests that excessive body weight is linked with a higher risk of getting PTC, while its impact on the aggressiveness of the disease, if present, is still not clear. Therefore, while attention should be paid to discover thyroid cancer in patients with obesity earlier, once diagnosed it should be managed following a conventional workup as in normal weight patients, based on the clinical presentation of the disease and including active surveillance if appropriate, as recommended by referral guidelines.

Different Changes in Adipokines, Lipid Profile, and TNF-Alpha Levels between 10 and 20 Whole Body Cryostimulation Sessions in Individuals with I and II Degrees of Obesity

Obesity is associated with chronic inflammation. While cold therapy influences the pro/antioxidative status of an individual, by affecting adipokine levels and the lipid profile, the effect of body mass index (BMI) on the response to cold exposure is unclear. We analyzed the link between BMI and the differences in effects of whole-body stimulation, depending on the number of treatments, on specific physiological parameters in men. Twenty-seven non-active men were divided into three groups: N (n = 9, BMI < 24.9), IOb (n = 9, BMI 30.0–34.9), and IIOb (BMI ≥ 35.0). The subjects participated in 20 3-min cryochamber sessions (−120 °C), 1/day, 5 days/week. Body composition was analyzed before and after treatment. Blood adiponectin (ADP), leptin (LEP), and tumor necrosis factor alpha (TNF-alpha) levels, and the lipid profile were analyzed three times: at baseline and up to 2 h after 10 and 20 sessions. The 20 treatments caused significant changes in body composition. Between 10 and 20 whole-body cryostimulation (WBC) sessions, a significant decreased was observed in the LEP and TNF-alpha levels. No significant changes in the lipid profile were noted. However, a positive tendency to regain the metabolic balance in adipose tissue was apparent in the IOb group in the tested period (decreased TG levels, increased HDL levels or the HDL/LDL ratio, and significantly decreased visceral adiposity index levels). Collectively, for people with obesity increasing the number of treatments above the standard 10 should be recommended.

Association between adipokines and thyroid carcinoma: a meta-analysis of case-control studies

Background

The incidence of thyroid carcinoma is increasing all over the world. Some studies have suggested that the change of adipokines expression can induce thyroid carcinoma. However, other studies have come to the opposite conclusion. Therefore, we studied the relationship between adipokines and thyroid carcinoma.

Methods

Databases—PubMed, Cochrane Library, SinoMed, CNKI, Wanfang, and clinical trial registries were searched. A meta-analysis was then performed through a fixed or random-effects model to calculate I values for heterogeneity analysis.

Results

Twenty-nine articles were finally included for analysis. The level of serum tumor necrosis factor-alpha (TNF-α) [standardized mean difference (SMD) =1.31, 95% confidence interval (95% CI): 0.35 to 2.28, I² = 98%, P = 0.008] and the ratio of TNF-α immunoreactivity in tissues [odds ratios (OR) =6.36, 95% CI: 1.92 to 21.05, I² = 66%, P = 0.002] in thyroid carcinoma are significantly higher than those in control. The serum interleukin-6 (IL-6) in patients with thyroid carcinoma is higher than that in control (SMD = 1.04, 95% CI: 0.40 to 1.67, I² = 96%, P = 0.001). There is no significant difference of the ratio of IL-6 immunoreactivity in tissues between carcinoma and control (OR = 1.23, 95% CI: 0.62 to 2.43, I² = 86%, P = 0.55). The ratio of leptin immunoreactivity in tissues is significantly associated with the risk of thyroid carcinoma (OR = 12.21, 95% CI: 3.36 to 44.40, I² = 85%, P < 0.00001). However, after analyzing the expression level of serum adiponectin in three studies, no significant difference is found between thyroid carcinoma and the control (P = 0.81).

Conclusions

Adipokines (TNF-α, IL-6 and leptin) show a strong relationship between elevated concentrations (in serum and/or tissue) and thyroid carcinoma. However, the association between adiponectin and thyroid carcinoma needs further research.

The pro-inflammatory marker soluble suppression of tumorigenicity-2 (ST2) is reduced especially in diabetic morbidly obese patients undergoing bariatric surgery

BACKGROUND

High soluble suppression of tumorigenicity-2 (sST2) is a marker of poor prognosis in chronic inflammatory conditions. ST2 and its ligand interleukin (IL)-33 are elevated in adipose tissue of obese individuals. We aimed to evaluate circulating sST2 and IL-33 as possible markers of metabolic benefit in morbidly overweight patients after Roux-en-Y gastric bypass (RYGB) bariatric surgery.

METHODS

sST2, IL-33, high sensitive IL-6, high sensitive C-reactive protein (hsCRP), leptin, cholesterol metabolism and liver parameters were measured in 80 morbidly obese individuals before and 1 year after bariatric surgery.

RESULTS

sST2 was higher (P = 0.03) in diabetics as compared to individuals without diabetes. Baseline sST2 was also higher in males than in females (P= 0.0002). One year after bariatric surgery, sST2 levels were decreased (median 120, IQR 59-176 pg/mL) as compared to sST2 before surgery (median 141, IQR 111-181, P = 0.0024), and the diabetic group showed most pronounced reduction in sST2 (P = 0.0016). An association was found between sST2 and liver function parameters before and after bariatric surgery, and between baseline sST2 and total cholesterol, triglyceride, total low density lipoprotein (LDL), small dense LDL, Apolipoprotein B as well as with small dense high density lipoproteins (HDL). In the subgroup of diabetic patients positive correlation between IL-33 and sST2 (r = 0.44, P = 0.05) was noticed.

CONCLUSIONS

Circulating sST2 is associated with markers of liver functions and lipid metabolism in severely obese patients and a reduction of sST2 was shown after successful bariatric surgery, most prominently in diabetic patients.

Inflammatory Signaling and Brown Fat Activity

Obesity is characterized by a state of chronic inflammation in adipose tissue mediated by the secretion of a range of inflammatory cytokines. In comparison to WAT, relatively little is known about the inflammatory status of brown adipose tissue (BAT) in physiology and pathophysiology. Because BAT and brown/beige adipocytes are specialized in energy expenditure they have protective roles against obesity and associated metabolic diseases. BAT appears to be is less susceptible to developing inflammation than WAT. However, there is increasing evidence that inflammation directly alters the thermogenic activity of brown fat by impairing its capacity for energy expenditure and glucose uptake. The inflammatory microenvironment can be affected by cytokines secreted by immune cells as well as by the brown adipocytes themselves. Therefore, pro-inflammatory signals represent an important component of the thermogenic potential of brown and beige adipocytes and may contribute their dysfunction in obesity.

Reduction of Premature Aging Markers After Gastric Bypass Surgery in Morbidly Obese Patients

Background

Obesity is considered to be a major comorbidity. Obese patients suffer from an increased proinflammatory state associated with a premature aging phenotype including increased secretion of senescence-associated secretory proteins (SASP) and reduced telomere length. Micro-ribonucleic acids (miRNAs) are non-coding RNA molecules that could modify the post-transcriptional process. Several studies have reported associations between miRNAs and metabolic unhealthy conditions.

Aim

To determine if bariatric surgery and the resulting weight loss could reverse the premature aging phenotype.

Methods

We enrolled 58 morbidly obese patients undergoing bariatric surgery. Markers of premature aging including the SASP IL-6, CRP and PAI-1, 7 miRNAs, as well as telomere length and telomere oxidation in mononuclear cells were evaluated.

Results

Patients showed a significant drop of body mass index (BMI; 43.98 ± 3.5 versus 28.02 ± 4.1, p < 0.001). We observed a significant reduction in SASP including a reduction of 55% of plasma IL-6 levels (p = 0 < 0.001), 83% of CRP levels (p = 0.001) and 15% of plasma PAI-1 levels (p < 0.001). Telomere length doubled in the patient cohort (p < 0.001) and was accompanied by a reduction in the telomere oxidation index by 70% (p < 0.001). Telomere length was inversely correlated with telomere oxidation. The aging-associated miRNA miR10a_5p was upregulated significantly (p = 0.039), while the other tested miRNAs showed no difference.

Conclusion

Our data indicate a significant reduction of the proinflammatory SASP after bariatric surgery. We observed an increase in telomere length and reduced oxidative stress at telomeres. miR10a_5p which is downregulated during aging was upregulated after surgery. Overall, bariatric surgery ameliorated the premature aging phenotype.

Adiponectin, Obesity, and Cancer: Clash of the Bigwigs in Health and Disease

Adiponectin is one of the most important adipocytokines secreted by adipocytes and is called a “guardian angel adipocytokine” owing to its unique biological functions. Adiponectin inversely correlates with body fat mass and visceral adiposity. Identified independently by four different research groups, adiponectin has multiple names; Acrp30, apM1, GBP28, and AdipoQ. Adiponectin mediates its biological functions via three known receptors, AdipoR1, AdipoR2, and T-cadherin, which are distributed throughout the body. Biological functions of adiponectin are multifold ranging from anti-diabetic, anti-atherogenic, anti-inflammatory to anti-cancer. Lower adiponectin levels have been associated with metabolic syndrome, type 2 diabetes, insulin resistance, cardiovascular diseases, and hypertension. A plethora of experimental evidence supports the role of obesity and increased adiposity in multiple cancers including breast, liver, pancreatic, prostrate, ovarian, and colorectal cancers. Obesity mediates its effect on cancer progression via dysregulation of adipocytokines including increased production of oncogenic adipokine leptin along with decreased production of adiponectin. Multiple studies have shown the protective role of adiponectin in obesity-associated diseases and cancer. Adiponectin modulates multiple signaling pathways to exert its physiological and protective functions. Many studies over the years have shown the beneficial effect of adiponectin in cancer regression and put forth various innovative ways to increase adiponectin levels.

Bariatric surgery in morbidly obese individuals affects plasma levels of protein C and thrombomodulin

Obesity is associated with a prothrombotic milieu and an increased risk for thrombotic events. Bariatric surgery is the most effective treatment for obesity resulting in dramatic weight loss and reduced inflammation and extrinsic coagulation pathway activation. Blood samples were drawn from 60 patients undergoing Roux-en-Y gastric bypass surgery before and 1 year after the intervention. Protein C (PC), activated PC (APC), soluble thrombomodulin (TM), soluble E-selectin (E-Sel), prothrombin time (PT) and activated partial thromboplastin time (aPTT) were evaluated. Both PC (187.4 ± 64.5% before surgery to 118.1 ± 48% 1 year after surgery, p < 0.001) and APC (138.7 ± 64.4% before surgery to 69.1 ± 65.7% after surgery, p < 0.001) were reduced following surgical intervention. TM showed a similar behavior with a reduction of soluble TM after the procedure from 5.7 ± 2.6 to 3.2 ± 1.4 ng/ml (p < 0.001). Similarly, soluble E-Sel was reduced after surgery from 26.6 ± 12.7 to 5.5 ± 4.1 ng/ml (p < 0.001). In contrast, aPTT was not shortened but slightly increased from 29.1 ± 4.8 s. before surgery to 31 ± 4.4 s. (p = 0.001) after surgery and levels of PT were reduced after surgery to 89.6 ± 15.5% from an initial 97.5 ± 13.5% (p < 0.001). In conclusion, we demonstrate a reduction of PC and APC 1 year after bariatric surgery accompanied by a reduction in soluble TM and soluble E-Sel. The reduction of PC and APC is not paralleled by a reduction but in contrast by a prolongation of aPTT suggesting a compensatory upregulation of PC during obesity. The reduction of TM and E-Sel might hint towards an improved endothelial function in this cohort of patients.

Carnosine Supplementation Improves Serum Resistin Concentrations in Overweight or Obese Otherwise Healthy Adults: A Pilot Randomized Trial

Adipokines play an important role in the regulation of glucose metabolism. We have previously shown that carnosine supplementation in overweight or obese non-diabetic individuals improves glucose metabolism but does not change adiponectin concentrations. However, its effect on other adipokines has not been investigated. Herein we further determined the effect of carnosine supplementation on serum adipsin, resistin and leptin. Twenty-two overweight or obese otherwise healthy adults were randomly assigned to receive either 2 g of carnosine (n = 13) or identically looking placebo (n = 9) for 12 weeks. Serum adipsin, leptin and resistin were analyzed using a bead-based multiplex assay. Carnosine supplementation decreased serum resistin concentrations compared to placebo (mean change from baseline: −35 ± 83 carnosine vs. 35 ± 55 ng/mL placebo, p = 0.04). There was a trend for a reduction in serum leptin concentrations after carnosine supplementation (−76 ± 165 ng/mL carnosine vs. 20 ± 28 ng/mL placebo, p = 0.06). The changes in leptin and resistin concentrations were inversely related to the change in concentration for urinary carnosine (r = −0.72, p = 0.0002; r = −0.67, p = 0.0009, respectively), carnosine-propanal (r = −0.56, p = 0.005; r = −0.63, p = 0.001, respectively) and carnosine-propanol (r = −0.61, p = 0.002; r = −0.60, p = 0.002, respectively). There were no differences between groups in change in adipsin concentrations. Our findings show carnosine supplementation may normalize some, but not all, of the serum adipokine concentrations involved in glucose metabolism, in overweight and obese individuals. Further clinical trials with larger samples are needed to confirm these results.

Comparative gene expression profile and DNA methylation status in diabetic patients of Kazak and Han people

We attempted to investigate the mechanism and susceptibility genes for diabetes in Han and Kazak ethnic individuals.The abdominal omental adipose tissues were obtained from diabetic cases and healthy controls. The gene expression and methylation data were produced for Kazak and Han individuals, respectively, and analyzed by bioinformatics analysis.We obtained 921 differentially expressed genes (DEGs) in Han group and 1772 in Kazak group. DEGs in Han group were significantly related with type 2 diabetes mellitus, and biosynthesis of amino acids, while the DEGs specific to Kazak patients were significantly enriched in metabolism-related pathways such as carbon metabolism, propanoate metabolism, and 2-oxocarboxylic acid metabolism. Major facilitator superfamily domain containing 1 (MFSD1) was found to be a methylation associated gene at hypermethylation site of cg16289538 in Han group. Rho guanine nucleotide exchange factor 1 (ARHGEF1) was the susceptible gene corresponding to the methylation sites of cg18800192 and cg00759295 in Kazak group. ARHGEF1 was also a node in protein-protein interaction network and significantly enriched in hsa04270: vascular smooth muscle contraction pathways.The molecular mechanism of diabetes may be different in Han and Kazak patients. MFSD1 and ARHGEF1 may be the diabetes susceptible genes.

The Relationship of adiponectin level and ADIPOQ gene variants with BMI among young adult women

The current study examined the effect of single nucleotide (SNPs) polymorphisms in the ADIPOQ gene (I146T and G276T) on body mass index (BMI) of young adult women. The women were divided into underweight, normal, overweight and obese according to BMI. The circulating levels of adiponectin were measured using commercially available ELISA kits. Genetic polymorphisms were genotyped using the PCR-RFLP method. G276T and I164T SNPs are common in the examined population as the frequency of G allele of 276 SNP was 54.8% and for the T allele of 164 SNP it was 41.7%. Circulating adiponectin levels were related to BMI and were lowest in the obese versus overweight, normal weight and underweight groups (p<0.01). However, ADIPOQ gene SNPs (I146T and G276T) showed no association with BMI groups. In conclusion, the results may suggest that adiponectin level, but not ADIPOQ gene SNPs, is a good indicator to BMI in young adult women.

New insights into the role of adipose tissue in thrombosis

Central obesity is independently associated with an elevated risk of cardiovascular disease, particularly thrombotic complications. Increasing data supports a link between excess body weight and the risk to suffer acute myocardial infarction, stent thrombosis after percutaneous interventions, ischemic stroke and vein thrombosis. Experimental and in vitro data have provided insights as to the mechanisms currently presumed to increase the thrombotic risk in obese subjects. Obesity is characterized by a chronic low grade inflammation and systemic oxidative stress that eventually damage the endothelium losing its antithrombotic properties. Obesity also stimulates the expression of leptin and attenuates adiponectin release, a protective adipokine. Although the contribution of adipokines to thrombosis has been questioned, recent work has suggested that they enhance platelet activation and, although to a lesser extent, induce the coagulation cascade through tissue factor (TF) expression. Increased body weight also impairs platelet sensitivity to insulin signaling and enhances the production of bioactive isoprostanes further promoting platelet reactivity. Finally, obese subjects have shown elevated circulating levels of von Willebrand factor, TF, factor VII and VIII, and fibrinogen, favoring a mild-to-moderate hypercoagulable state, and, on the other hand, increased secretion of plasminogen activator inhibitor (PAI)-1 and thrombin activatable fibrinolysis inhibitor (TAFI) contributing to impair the fibrinolytic system. In the present review, we provide an overview of the impact of excess body weight on thrombosis. We will focus on the link between dysfunctional adipose tissue and endothelial damage, platelet reactivity, enhanced coagulation and impaired fibrinolysis; mechanisms currently recognized to increase arterial thrombotic risk in obese subjects.

The polyunsaturated fatty acid balance in kidney health and disease: A review

Epidemiological studies show that circulating polyunsaturated fatty acids contribute to preserve renal function. In renal disease states there is generally a lack of omega-3 long chain polyunsaturated fatty acids (n-3 LCPUFA) as measured in biological samples, but despite intense research for more than 30 years, it is still unclear how and to what extent their supplementation would benefit kidney disorders. Studies evaluating the n-6 series and the kidney are less frequent. The last compilation of clinical trials with n-3 LCPUFA supplements focusing on renal function and damage dates back to 2012. We here discuss n-3 and n-6 fatty acids in relation to the kidney summarizing single- and double blind randomized controlled trials performed between 2012 and 2016. Nine were sub-studies/post-hoc analyses of previous parent trials. Twelve out of the twenty trials reported on fatty acid profile or fatty acid species. Factors that may explain inconsistent results obtained after supplementation with the n-3 LCPUFA EPA and DHA in kidney disease are discussed such as baseline levels determining response, drug interaction. The need of evaluating fatty acid status before and after intervention is emphasized, to match changes in outcome measure with changes of any fatty acid potentially involved.

Treatment of venous thromboembolism with rivaroxaban in relation to body weight

The pharmacokinetics of oral rivaroxaban are highly predictable and only affected to a limited extent by bodyweight; therefore, dose adjustments for bodyweight are not required. However, this raises concerns among physicians for potential under- or overdosing. This substudy of the randomised EINSTEIN DVT and EINSTEIN PE trials, which compared rivaroxaban with enoxaparin/vitamin K antagonist (VKA) therapy, aimed to determine the incidence of major bleeding in patients with a low bodyweight and recurrent venous thromboembolism (VTE) in patients with a high bodyweight during rivaroxaban or enoxaparin/VKA therapy. More than 8,000 patients with objectively diagnosed deepvein thrombosis or pulmonary embolism were included. Adjusted hazard ratios for recurrent VTE and bleeding were calculated using the Cox proportional hazards model. Analyses were performed for both the first 21 days of treatment and the whole treatment period. For rivaroxaban recipients, there was no association between bodyweight or body mass index (BMI) and risk of recurrent VTE (ptrend=0.87 and 0.62, respectively), major bleeding (ptrend=0.24 and 0.36, respectively) or clinically relevant bleeding (ptrend=0.17 and 0.63, respectively). Major bleeding events were numerically lower in rivaroxaban patients across all bodyweight and BMI categories. Hazard ratios for rivaroxaban vs enoxaparin/VKA were similar in all bodyweight and BMI categories, both during the first 21 days and the whole treatment period. The fixed-dose rivaroxaban regimen is not associated with an increased risk of major bleeding or recurrent VTE in patients with either a low or high bodyweight. A high BMI was not associated with an increased risk of recurrent VTE during anticoagulation.

Note: This study was presented at the 25th Congress of the International Society on Thrombosis and Haemostasis; June, 2015, Toronto, Canada. Trial registration: EINSTEIN DVT (NCT00440193), EINSTEIN PE (NCT00439777).

Joint analysis of left ventricular expression and circulating plasma levels of Omentin after myocardial ischemia

BACKGROUND

Omentin-1, also known as Intelectin-1 (ITLN1), is an adipokine with plasma levels associated with diabetes, obesity, and coronary artery disease. Recent studies suggest that ITLN1 can mitigate myocardial ischemic injury but the expression of ITLN1 in the heart itself has not been well characterized. The purpose of this study is to discern the relationship between the expression pattern of ITLN1 RNA in the human heart and the level of circulating ITLN1 protein in plasma from the same patients following myocardial ischemia.

METHODS

A large cohort of patients (n = 140) undergoing elective cardiac surgery for aortic valve replacement were enrolled in this study. Plasma and left ventricular biopsy samples were taken at the beginning of cardiopulmonary bypass and after an average of 82 min of ischemic cross clamp time. The localization of ITLN1 in epicardial adipose tissue (EAT) was also further characterized with immunoassays and cell fate transition studies.

RESULTS

mRNA expression of ITLN1 decreases in left ventricular tissue after acute ischemia in human patients (mean difference 280.48, p = 0.001) whereas plasma protein levels of ITLN1 increase (mean difference 5.24, p < 0.001). Immunohistochemistry localized ITLN1 to the mesothelium or visceral pericardium of EAT. Epithelial to mesenchymal transition in mesothelial cells leads to a downregulation of ITLN1 expression.

CONCLUSIONS

Myocardial injury leads to a decrease in ITLN1 expression in the heart and a corresponding increase in plasma levels. These changes may in part be due to an epithelial to mesenchymal transition of the cells that express ITLN1 following ischemia. Trial Registration Clinicaltrials.gov ID: NCT00985049.

WAT-on-a-chip: a physiologically relevant microfluidic system incorporating white adipose tissue

Organ-on-a-chip systems possess a promising future as drug screening assays and as testbeds for disease modeling in the context of both single-organ systems and multi-organ-chips. Although it comprises approximately one fourth of the body weight of a healthy human, an organ frequently overlooked in this context is white adipose tissue (WAT). WAT-on-a-chip systems are required to create safety profiles of a large number of drugs due to their interactions with adipose tissue and other organs via paracrine signals, fatty acid release, and drug levels through sequestration. We report a WAT-on-a-chip system with a footprint of less than 1 mm2 consisting of a separate media channel and WAT chamber connected via small micropores. Analogous to the in vivo blood circulation, convective transport is thereby confined to the vasculature-like structures and the tissues protected from shear stresses. Numerical and analytical modeling revealed that the flow rates in the WAT chambers are less than 1/100 of the input flow rate. Using optimized injection parameters, we were able to inject pre-adipocytes, which subsequently formed adipose tissue featuring fully functional lipid metabolism. The physiologically relevant microfluidic environment of the WAT-chip supported long term culture of the functional adipose tissue for more than two weeks. Due to its physiological, highly controlled, and computationally predictable character, the system has the potential to be a powerful tool for the study of adipose tissue associated diseases such as obesity and type 2 diabetes.

Low adiponectin is associated with diastolic dysfunction in women: a cross-sectional study from the Tromsø Study

Background

Heart failure with preserved ejection fraction is closely associated with diastolic dysfunction and related to obesity and female sex. We investigated whether adiponectin, an adipocyte-secreted protein hormone with cardioprotective effects, was associated with indices of diastolic dysfunction, and whether the association was sex dependent.

Methods

We conducted a cross-sectional study on 1165 women and 896 men without diabetes. We stratified the multivariable adjusted logistic regression analyses and the fractional polynomial regression analyses according to sex, with echocardiographic markers of diastolic dysfunction as dependent variables, and adiponectin as the independent variable of interest.

Results

Decreased adiponectin was associated with higher odds of average tissue Doppler e’ < 9 in women (odds ratio [OR] 1.17 per 1 μg/mL adiponectin decrease, 95% confidence interval [CI] 1.04–1.30), but not in men (p for interaction with sex 0.04). Women, but not men, had higher odds of E/e’ ratio ≥ 8 with lower adiponectin (OR 1.12 per 1 μg/mL adiponectin decrease, 95% CI 1.02–1.24, p for interaction with sex 0.04). Adiponectin in the lower sex-specific tertile was associated with increased odds of concentric left ventricular hypertrophy in women (OR 2.44, 95% CI 1.03–5.77), but with decreased odds in men (OR 0.32, 95% CI 0.11–0.88, p for interaction with sex 0.002), and decreased odds of eccentric hypertrophy in men only (OR 0.53, 95% CI 0.33–0.88, p for interaction with sex 0.02). Adiponectin in the lower sex-specific tertile was associated with moderately enlarged left atria in women only (OR 1.43, 95% CI 1.01–2.03, p for interaction with sex 0.04). Finally, adiponectin had a non-linear relationship with left ventricular mass in women only, with exponentially increasing left ventricular mass with lower adiponectin levels (p for interaction with sex 0.01).

Conclusions

Low adiponectin was associated with higher odds of indices of diastolic dysfunction in women, but lower odds of indices of diastolic dysfunction in men. Lower adiponectin was associated with increased left ventricular mass in women only.

Peptide-based vaccination against OPN integrin binding sites does not improve cardio-metabolic disease in mice

Obesity causes insulin resistance via a chronic low-grade inflammation. This inflammation is characterized by elevated pro-inflammatory markers and macrophage accumulation in the adipose tissue (AT). AT inflammation is a key factor causing insulin resistance and thus type 2 diabetes, both linked to atherosclerotic cardiovascular disease. Osteopontin (OPN), a well-known inflammatory cytokine, is involved in obesity-linked complications including AT inflammation, insulin resistance, atherosclerosis and CVD. During inflammation, OPN is proteolytically cleaved by matrix metalloproteinases or thrombin leading to increased OPN activity. Therefore, OPN provides a new interesting target for immunological prevention and treatment of obesity-associated diseases. The aim of our study was to evaluate peptide-based vaccines against integrin binding sites of OPN and to examine whether these active immunotherapies are functional in reducing metabolic tissue inflammation, insulin resistance, and atherosclerosis in a cardio-metabolic (Ldlr^-/- mice) and a diet-induced obesity model (WT mice). However, atherosclerosis, insulin resistance and AT inflammation were not diminished after treatment with OPN-derived peptides in murine models. Lack of efficacy was based on a failure to induce antibodies capable to bind epitopes in the context of functional OPN protein. In conclusion, our data point to unexpected challenges in the immunotherapeutic targeting of adhesive motives, such as RGD containing sequences, on endogenous proteins.

Potential beneficial effect of some adipokines positively correlated with the adipose tissue content on the cardiovascular system

Obesity is a risk factor of cardiovascular diseases. However, in the case of heart failure, obese and overweight patients have a more favourable prognosis compared to patients who have a normal body weight. This phenomenon is referred to as the "obesity paradox," and it is explained by, among others, a positive effect of adipokines produced by adipose tissue, particularly by the tissue located in the direct vicinity of the heart and blood vessels. The favourable effect on the cardiovascular system is mostly associated with adiponectin and omentin, but the levels of these substances are reduced in obese patients. Among the adipokines which levels are positively correlated with the adipose tissue content, favourable activity is demonstrated by apelin, progranulin, chemerin, TNF-α (tumour necrosis factor-)α, CTRP-3 (C1q/tumour necrosis factor (TNF) related protein), leptin, visfatin and vaspin. This activity is associated with the promotion of regeneration processes in the damaged myocardium, formation of new blood vessels, reduction of the afterload, improvement of metabolic processes in cardiomyocytes and myocardial contractile function, inhibition of apoptosis and fibrosis of the myocardium, as well as anti-inflammatory and anti-atheromatous effects. The potential use of these properties in the treatment of heart failure and ischaemic heart disease, as well as in pulmonary hypertension, arterial hypertension and the limitation of the loss of cardiomyocytes during cardioplegia-requiring cardiosurgical procedures, is studied. The most advanced studies focus on analogues of apelin and progranulin.

[Omentin: Role in insulin resistance, inflammation and cardiovascular protection]

The omentin is an adipokine, which role is due to the capacity of regulate metabolic (insulin sensitivity) and anti-inflammatory activities, thus conferring vascular protection during obesity and diabetes mellitus type 2. By this, it is important to know the mechanisms by which omentin confers cardiovascular protection, with the purpose of establish omentin a possible therapeutic target or molecule on this scenario.

Lean mass, and not fat mass, is an independent determinant of carotid intima media thickness in obese subjects

BACKGROUND AND AIMS

Obesity is an important determinant of increased cardiovascular risk. Increased fat mass has been assumed to constitute the main prominent contributor to changes in carotid intima-media thickness (c-IMT).

METHODS

In 421 consecutive subjects (301 women), c-IMT was evaluated ultrasonographically in 6 independent territories and body composition was assessed by dual-energy X-ray absorptiometry.

RESULTS

c-IMT was positively associated with lean body mass in both men (r = 0.328, p = <0.0001) and women (r = 0.268 p = <0.0001) and increased across lean mass quartiles (p = <0.0001 for linear-trend ANOVA). Stepwise linear regression analysis showed that age and lean mass (but not fat mass or traditional cardiovascular risk factors) contributed to 46.2% of c-IMT variance in men (p = <0.0001). Even within obese men, lean mass was an independent contributor to c-IMT variance. Among women, age, lean mass and ultrasensitive CRP levels contributed independently to 47.7% of c-IMT variance (p < 0.0001).

CONCLUSIONS

Lean mass, and not fat mass, might contribute to increase c-IMT in obese patients independently of classical atherosclerotic risk factors. These data reinforce the concept that the increase in metabolically fat-free mass that accompanies the body weight enlargement is closely related to the raise in blood pressure.

Apolipoprotein E synthesized by adipocyte and apolipoprotein E carried on lipoproteins modulate adipocyte triglyceride content

Excessive energy storage of adipose tissue makes contribution to the occurrence and progression of obesity, which accompanies with multiple adverse complications, such as metabolic syndrome, cardiovascular diseases. It is well known that apolipoprotein E, as a component of lipoproteins, performs a key role in maintaining plasma lipoproteins homeostasis. Interestingly, apolipoprotein E is highly expressed in adipocyte and has positive relation with body fat mass. Apolipoprotein E knock-out mice show small fat mass compared to wild type mice. Moreover, adipocyte deficiency in apolipoprotein E shows impaired lipoproeteins internalization and triglyceride accumulation. Apolipopreotein E-deficient lipoproteins can not induce preadipocyte to form round full-lipid adipocyte, whereas apolipoprotein E-containing lipoproteins can. This article mainly reviews the modulation of apolipoprotein E synthesized by adipocyte and apolipoprotein E carried on lipoproteins in adipocyte triglyceride content.

New insight into adiponectin role in obesity and obesity-related diseases

Obesity is a major health problem strongly increasing the risk for various severe related complications such as metabolic syndrome, cardiovascular diseases, respiratory disorders, diabetic retinopathy, and cancer. Adipose tissue is an endocrine organ that produces biologically active molecules defined “adipocytokines,” protein hormones with pleiotropic functions involved in the regulation of energy metabolism as well as in appetite, insulin sensitivity, inflammation, atherosclerosis, cell proliferation, and so forth. In obesity, fat accumulation causes dysregulation of adipokine production that strongly contributes to the onset of obesity-related diseases. Several advances have been made in the treatment and prevention of obesity but current medical therapies are often unsuccessful even in compliant patients. Among the adipokines, adiponectin shows protective activity in various processes such as energy metabolism, inflammation, and cell proliferation. In this review, we will focus on the current knowledge regarding the protective properties of adiponectin and its receptors, AdipoRs (“adiponectin system”), on metabolic complications in obesity and obesity-related diseases. Adiponectin, exhibiting antihyperglycemic, antiatherogenic, and anti-inflammatory properties, could have important clinical benefits in terms of development of therapies for the prevention and/or for the treatment of obesity and obesity-related diseases.

Atherothrombotic risk in obesity

A link between obesity and coronary artery disease development has been repeatedly proposed, possibly in part due to the development of a proinflammatory and prothrombotic state in obese subjects. Adipocytes secrete numerous hormones and cytokines (adipokines) which influence gene expression and cell functions in endothelial cells, arterial smooth muscle cells, and monocytes/macrophages favouring the development of an atherosclerotic vulnerable plaque. Moreover, the release of such biologically active molecules also promotes endothelial function impairment, disturbs the haemostatic and fibrinolytic systems, and produces alterations in platelet function affecting the initiation, progression, and stabilization of thrombus formation upon atherosclerotic plaque rupture. In this review we will discuss the pathophysiological mechanisms by which obesity contributes to increase atherothrombosis paying special attention to its effects over thrombosis.

Comprehensive analysis of circulating adipokines and hsCRP association with cardiovascular disease risk factors and metabolic syndrome in Arabs

Background

Cardiovascular diseases (CVD) are a leading cause of death worldwide including the Middle East. This is caused in part by the dysregulation of adipose tissue leading to increased production of pro-inflammatory adipokines and reduction in cardio-protective adipokines such as adiponectin. Ethnicity has been recognized as a major factor in the association between CVD risk factors and the different circulating adipokines. In this study, for the first time, the relationship between traditional cardiovascular risk factors, Metabolic Syndrome (MetS) and circulating level of adipokines in Arab ethnicity was investigated.

Methods

We conducted a population-based cross-sectional survey on 379 adult Arab participants living in Kuwait. Traditional cardiovascular risk factors such as blood pressure (BP), low density lipoprotein (LDL) and triglyceride (TG) were measured. Plasma levels of circulating Leptin, Plasminogen Activator Inhibitor (PAI-1) visfatin, adiponectin, resistin and adipsin were assessed using the multiplexing immunobead-based assay.

Results

Circulating levels of High sensitivity C-Reactive Protein (hsCRP), Leptin, PAI-1 and adiponectin were significantly higher in Arab women than men (p < 0.0001). In multi-variate analysis, the homeostasis model assessment-insulin resistance (HOMA-IR) and body mass index (BMI) showed strong association with most of the biomarkers (p < 0.05). HsCRP showed significant association with all risk factors (p < 0.05). Leptin, PAI-1 and adipsin showed significant positive correlation with BMI, unlike adiponectin which showed inverse correlation (p < 0.05). Subjects in the highest tertile of leptin, PAI-1 and hsCRP had higher odds of having Metabolic Syndrome (MetS) (odd ratio [OR] = 3.02, 95% confidence interval [CI] = 1.47 – 6.19) and (OR = 2.52, 95% CI = 1.45 – 4.35), (OR = 4.26, 95% CI = 2.39 – 7.59) respectively. On the other hand subjects with highest tertile of adiponectin had lower odds of having MetS (OR = 0.22, 95% CI = 0.12 – 0.40). Leptin, PAI-1 and hsCRP showed significant positive association with increased MetS components (P-trend <0.05), while adiponectin was negatively associated with increased MetS components (P-trend <0.0001).

Conclusion

Our results show positive association between hsCRP, leptin, PAI-1 with increased MetS components and increase the odds of having MetS. Adiponectin on the other hand showed inverse correlation with MetS components and associated with reduction in MetS. Overall, our data highlights the significant clinical value these markers have in MetS especially hsCRP which can be used as good marker of low grade inflammation in Arabs.