The relation of adipose tissue to cardiometabolic risk

Males With Traumatic Lower Limb Loss Differ in Body Fat Distribution Compared to Those Without Limb Loss

OBJECTIVES

The primary objective was to examine body fat composition in males with traumatic lower limb loss and a comparison group without limb loss. A secondary objective was to determine if there are differences in body fat composition by traumatic limb loss level.

RESEARCH METHODS AND PROCEDURES

Cross-sectional analyses of baseline in-person intake data was completed at a large military medical center. Data were collected from 2011 to 2020, and analysis was conducted in 2020. Participants (n = 89) included males who sustained traumatic lower limb loss (n = 50) and an age-matched comparison group without limb loss (n = 39). Mean age of participants was 36.0 ± 13.2 years. Main outcomes measured included age, height, body mass index, weight, body fat mass and percent, android fat mass and percent, gynoid fat mass and percent, and android/gynoid percent fat ratio. Differences between groups were assessed using t-tests or Mann-Whitney U tests. Differences between limb loss levels were assessed using one-way ANOVA or Wilcoxon signed-rank test.

RESULTS

Body fat percent (P = .001), gynoid fat percent (P = .010), android fat mass (P = .01), and percent (P = .02) were higher in the group with limb loss. There were no differences in body fat composition between limb loss levels (P > .05).

CONCLUSION

Males with traumatic lower limb loss had a higher body fat percent compared to those without limb loss. Given higher body fat composition in individuals with limb loss and the relationship between body fat composition and cardiovascular disease risk, including body composition analysis with clinical screening could identify changes and allow for early intervention.

The Pivotal Role of Adipocyte-Na K peptide in Reversing Systemic Inflammation in Obesity and COVID-19 in the Development of Heart Failure

This review summarizes data from several laboratories that have demonstrated a role of the Na/K-ATPase, specifically its α1 subunit, in the generation of reactive oxygen species (ROS) via the negative regulator of Src. Together with Src and other signaling proteins, the Na/K-ATPase forms an oxidant amplification loop (NKAL), amplifies ROS, and participates in cytokines storm in obesity. The development of a peptide fragment of the α1 subunit, NaKtide, has been shown to negatively regulate Src. Several groups showed that the systemic administration of the cell permeable modification of NaKtide (pNaKtide) or its selective delivery to fat tissue-adipocyte specific expression of NaKtide-ameliorate the systemic elevation of inflammatory cytokines seen in chronic obesity. Severe acute respiratory syndrome - coronavirus 2 (SARS-CoV-2), the RNA Coronavirus responsible for the COVID-19 global pandemic, invades cells via the angiotensin converting enzyme 2 (ACE-2) receptor (ACE2R) that is appended in inflamed fat tissue and exacerbates the formation of the cytokines storm. Both obesity and heart and renal failure are well known risks for adverse outcomes in patients infected with COVID-19. White adipocytes express ACE-2 receptors in high concentration, especially in obese patients. Once the virus invades the white adipocyte cell, it creates a COVID19-porphyrin complex which degrades and produces free porphyrin and iron and increases ROS. The increased formation of ROS and activation of the NKAL results in a further potentiated formation of ROS production, and ultimately, adipocyte generation of more inflammatory mediators, leading to systemic cytokines storm and heart failure. Moreover, chronic obesity also results in the reduction of antioxidant genes such as heme oxygenase-1 (HO-1), increasing adipocyte susceptibility to ROS and cytokines. It is the systemic inflammation and cytokine storm which is responsible for many of the adverse outcomes seen with COVID-19 infections in obese subjects, leading to heart failure and death. This review will also describe the potential antioxidant drugs and role of NaKtide and their demonstrated antioxidant effect used as a major strategy for improving obesity and epicardial fat mediated heart failure in the context of the COVID pandemic.

Weight-Loss Diets, Adiponectin, and Changes in Cardiometabolic Risk in the 2-Year POUNDS Lost Trial

CONTEXT

Compelling evidence suggests that the beneficial effects of weight-loss diet interventions on improvement of cardiometabolic risk factors may be partly through modulating secretion of adiponectin from adipose tissue.

OBJECTIVE

To investigate the effects of long-term weight-loss diets with different compositions of macronutrients on longitudinal changes in circulating adiponectin concentrations and how such changes, if they exist, affect cardiometabolic risk.

DESIGN, SETTING, AND PARTICIPANTS

In the 2-year Preventing Overweight Using Novel Dietary Strategies trial, 811 overweight or obese adults were randomly assigned to 1 of 4 diets varying in macronutrient intakes. The current analysis was restricted to participants who had baseline adiponectin measurement (n = 768). Circulating concentrations of adiponectin and cardiometabolic outcomes were repeatedly measured at baseline, 6 months, and 2 years.

MAIN OUTCOME MEASURES

Circulating concentrations of adiponectin and cardiometabolic risk factors.

RESULTS

Weight-loss diet interventions significantly increased circulating adiponectin concentrations over 2 years, similarly in 4 diet groups (P value for difference >.05). We found that the increase of adiponectin was significantly associated with reduction of waist circumference and low-density lipoprotein cholesterol, but associated with increase of high-density lipoprotein cholesterol (P < .001 for each), after adjusting for age, sex, ethnicity, follow-up time, diet group, baseline body mass index, baseline level of respective outcome trait, and concurrent weight change.

CONCLUSIONS

Our findings indicate that long-term interventions by weight-loss diets varying in macronutrients similarly increase circulating adiponectin, which may particularly improve abdominal fat distribution and lipid metabolism independently of weight change.

Tumor Necrosis Factor-Α, Interleukin-6, C-Reactive Protein Levels and Insulin Resistance Associated with Type 2 Diabetes in Abdominal Obesity Women

We aim to investigate the association between elevated tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and high sensitivity-C-reactive protein (hs-CRP) with type 2 diabetes mellitus (T2DM) in abdominal obesity (AO) women subjects. A total of 428 AO subjects (age 48.4 ± 10.2 years), and 107 non-AO women subjects (age 48.8 ± 11.8 years) were enrolled for the all biochemistry testing, inflammatory cytokines, fasting insulin and Homeostasis Model Assessment of insulin resistance (HOMA-IR). Body mass index, waist circumference (WC), blood pressure (BP), plasma glucose (Glu), triglyceride (TG), insulin, HOMA-IR and inflammatory cytokines were significantly higher and lower total antioxidant capacity, HDL-C in AO subjects (p < 0.05). WC was significantly correlated with BP, Glu, TG, LDL-C, insulin, HOMA-IR, TNF-α, IL-6 and negative correlation with HDL-C in AO subjects. Elevation of TNF-α, IL-6, hs-CRP and insulin resistance were significantly associated with T2DM in AO subjects, after adjusting with insulin resistance, increased oxidative stress, elevated TG and reduced HDL-C by using multiple logistic regression analysis. In conclusions, elevation of inflammatory cytokines, oxidative stress and insulin resistance were associated with T2DM in AO women subjects. These inflammatory cytokines are positively associated with T2DM and may have a causal relation with an increased oxidative stress and insulin resistance in these AO women subjects.

Measurement and Interpretation of Body Mass Index During Childhood and Adolescence

The landscape of childhood health and disease has changed over the past century, and school nurses are now in a unique position to address the conditions that lead to chronic disease, such as obesity. Measuring body mass index (BMI) during childhood and adolescence is the recommended method for screening and/or monitoring obesity in school communities. Yet changes in the size, proportion, and distribution of fat mass and fat-free mass during growth and development introduce challenges to interpreting BMI measurements. Understanding these challenges and ensuring accurate measurement techniques are the foundation for implementing school-based BMI measurement programs. This article will provide an overview of body composition during childhood and adolescence, introduce strategies to improve the accuracy of BMI measurements, and explore the school nurse's role in BMI surveillance and/or screening activities.

Prevalence of obesity in children aged 6-12 years in Greece: nutritional behaviour and physical activity

INTRODUCTION

During the last two decades, obesity has proved to be one of the most important problems of public health, and it is considerably more frequent in developed countries, not only in adults, but in children, too. The aim of the current study is to evaluate the prevalence of overweight and obesity in children.

MATERIAL AND METHODS

Two thousand three hundred and seventy-four pupils in primary education were considered for the study (1206 boys and 1168 girls).

RESULTS

In the population-based study, the proportion of overweight children was 23.9%, of obese children 7.3%, and of those with central obesity 35.5%. The boys were obese in a higher percentage than the girls (9.2% vs. 5.3%, p < 0.05). The obesity rates were gradually reduced as the children were growing older. The nutritional habits which were identified to have a positive association with obesity were the following: skipping breakfast, not consuming fruits and vegetables, and consuming bread and soft drinks. Children's healthy nutrition in school was related to lower rates of generalised and central obesity, while the hours spent watching TV were positively associated with all types of obesity.

CONCLUSIONS

Results from the study suggest that a high proportion of children are overweight or obese. Therefore, it is important to adhere to a healthy lifestyle which emphasizes healthy food choices and habits, regular physical activity, and limiting screen time.

Drug treatment of obesity in cardiovascular disease

Obesity is a significant health problem worldwide and is associated with a number of co-morbidities including type 2 diabetes mellitus, hypertension, dyslipidemia, obstructive sleep apnea, and cardiovascular disease. A number of different pathophysiologic mechanisms including increased inflammation, oxidative stress, and insulin resistance have been associated with initiation and progression of atherosclerotic disease in obese individuals. Lifestyle modifications have provided modest results in weight reduction and the focus of interest has now shifted towards drug development to treat severely obese individuals with a body mass index (BMI) >30 kg/m(2) or those with a BMI >27 kg/m(2) who have additional co-morbidities. Different regimens focusing on dietary absorption or acting centrally to control hunger and food intake have been developed. However, their weight loss effect is, in most cases, modest and this effect is lost once the medication is discontinued. In addition, long-term use of these drugs is limited by significant side effects and lack of long-term safety and efficacy data. Orlistat is the only US FDA-approved medication for long-term use. A number of new medications are currently under investigation in phase III trials with promising preliminary results. This review comments on available anti-obesity pharmacologic regimens, their weight-loss benefit, and their impact on cardiovascular risk factors.

Tissue Factor, Tissue Factor Pathway Inhibitor and Factor VII Activity in Cardiovascular Complicated Type 2 Diabetes Mellitus

OBJECTIVES

Tissue factor (TF) is the main initiator of the extrinsic coagulation pathway through factor VII (FVII) activation, which is physiologically inhibited by tissue factor pathway inhibitor (TFPI). Alteration of this pathway has been described in Type 2 diabetes mellitus (T2DM). The aim of this study is to assess TF and TFPI plasma levels and FVII coagulant activity (FVIIa) in T2DM in relation to cardiothrombotic disease and their correlation to metabolic and clinical behavior of the patients.

METHODS

The study was conducted on 80 T2DM patients divided to accordingly; groupI: 40 patients without a history or clinically detected heart disease, and groupII: 40 patients with a history of myocardial infarction compared to 30 controls. The patients were recruited from Ain Shams University diabetes clinic from September 2007 to February 2009 after informed consent was obtained. Peripheral blood samples were taken for measurement of plasma TF and TFPI levels using ELISA technique and quantitative FVIIa using FVII deficient plasma.

RESULTS

Plasma levels of TF, TFPI and FVIIa were significantly higher in T2DM patients compared to the controls (p<0.001). TF (236.50±79.23)and TFPI (242.33±85.84)were significantly higher in group II, compared to group I (150.33±81.16), (152.8± 82.46), (p<0.001). TF and TFPI were significantly correlated to body mass index and glycemic control. Also, TF and TFPI were significantly higher in hypertensives (p=0.001) and dyslipidemics (p=0.006) but not in smokers (p=0.64), (p=0.11) respectively.

CONCLUSION

There was a correlation between high TF, TFPI plasma levels, FVIIa activity and cardiothrombotic complications in T2DM especially in the presence of high risk factors such as poor glycemic control, dyslipidemia and obesity. Future target therapy against TF may be beneficial for T2DM patients.

Cannabinoid type 1 receptor mediates depot-specific effects on differentiation, inflammation and oxidative metabolism in inguinal and epididymal white adipocytes

Objective:

The endocannabinoid system is a major component in the control of energy metabolism. Cannabinoid 1 (CB1)-receptor blockade induces weight loss and reduces the risk to develop the metabolic syndrome with its associated cardiovascular complications. These effects are mediated by central and peripheral pathways. Interestingly, weight loss is mainly achieved by a reduction of visceral fat mass. We analyzed fat depot-specific differences on adipocyte differentiation, inflammation and oxidative metabolism in CB1-receptor knockout cells.

Materials and methods:

We used newly generated epididymal/inguinal adipose cell lines from CB1-receptor knockout mice. Differences in differentiation were measured by fat-specific Oil Red O staining and quantitative analysis of key differentiation markers. Induction of apoptosis was evaluated by cell death detection and investigation of p53 phosphorylation. Inflammation markers were quantified by real-time PCR. For analyzing the process of transdifferentiation we measured oxygen consumption and mitochondrial biogenesis.

Results:

Differentiation was reduced in visceral adipocytes from CB1-receptor knockout mice as compared with wild-type controls. Moreover, we found an induction of apoptosis in these cells. In contrast, subcutaneous adipocytes from CB1-receptor knockout mice showed an accelerated differentiation and a reduced rate of apoptosis. Inflammation was increased in visceral fat cells, as analyzed by the expression pattern of interleukin-6, monocyte chemoattractant protein 1 (MCP-1), tumor necrosis factor-α, whereas in subcutaneous adipocytes these markers were decreased. Furthermore, subcutaneous CB1-receptor knockout cells were more sensitive toward a conversion into a brown fat phenotype. Uncoupling protein-1 as well as PGC-1α expression was significantly elevated. This was accompanied by an increase in mitochondrial biogenesis and oxygen consumption.

Conclusion:

In conclusion, we found depot-specific effects on differentiation, apoptosis, inflammation and oxidative metabolism in CB1-receptor knockout cells. Thus, CB1-receptor-mediated pathways differentially target adipose tissue depots to a dual effect that minimizes cardiometabolic risk, on the one hand, by diminishing visceral fat, and that enhances thermogenesis in subcutaneous adipocytes, on the other.

Safety, tolerability and sustained weight loss over 2 years with the once-daily human GLP-1 analog, liraglutide

Objective:

Having demonstrated short-term weight loss with liraglutide in this group of obese adults, we now evaluate safety/tolerability (primary outcome) and long-term efficacy for sustaining weight loss (secondary outcome) over 2 years.

Design:

A randomized, double-blind, placebo-controlled 20-week study with 2-year extension (sponsor unblinded at 20 weeks, participants/investigators at 1 year) in 19 European clinical research centers.

Subjects:

A total of 564 adults (n=90–98 per group; body mass index 30–40 kg m⁻²) enrolled, 398 entered the extension and 268 completed the 2-year trial. Participants received diet (500 kcal deficit per day) and exercise counseling during 2-week run-in, before being randomly assigned (with a telephone or web-based system) to once-daily subcutaneous liraglutide (1.2, 1.8, 2.4 or 3.0 mg, n=90–95), placebo (n=98) or open-label orlistat (120 mg × 3, n=95). After 1 year, liraglutide/placebo recipients switched to liraglutide 2.4 mg, then 3.0 mg (based on 20-week and 1-year results, respectively). The trial ran from January 2007–April 2009 and is registered with Clinicaltrials.gov, number NCT00480909.

Results:

From randomization to year 1, liraglutide 3.0 mg recipients lost 5.8 kg (95% confidence interval 3.7–8.0) more weight than those on placebo and 3.8 kg (1.6–6.0) more than those on orlistat (P⩽0.0001; intention-to-treat, last-observation-carried-forward). At year 2, participants on liraglutide 2.4/3.0 mg for the full 2 years (pooled group, n=184) lost 3.0 kg (1.3–4.7) more weight than those on orlistat (n=95; P<0.001). Completers on liraglutide 2.4/3.0 mg (n=92) maintained a 2-year weight loss of 7.8 kg from screening. With liraglutide 3.0 mg, 20-week body fat decreased by 15.4% and lean tissue by 2.0%. The most frequent drug-related side effects were mild to moderate, transient nausea and vomiting. With liraglutide 2.4/3.0 mg, the 2-year prevalence of prediabetes and metabolic syndrome decreased by 52 and 59%, with improvements in blood pressure and lipids.

Conclusion:

Liraglutide is well tolerated, sustains weight loss over 2 years and improves cardiovascular risk factors.

Exploring the complexity of cardiometabolic risk in women

Cardiovascular disease (CVD) is the leading cause of death in the United States. Women are more likely than men to present with advanced disease and experience higher CVD-related morbidity and mortality. Metabolic syndrome is a constellation of risk factors for Type 2 diabetes mellitus (T2DM) and CVD. Abdominal adiposity, a component of metabolic syndrome, is associated with insulin resistance and promotes an atherogenic inflammatory milieu. Cardiometabolic risk (CMR) encompasses metabolic syndrome and incorporates other risk factors such as lifestyle choices, gender, and genetics as risk factors for CVD yet still does not include more recently recognized physiological risk factors such as vitamin D deficiency or psychosocial risk factors such as perceived stress and lack of social support. Because a more comprehensive view of CVD risk factors may facilitate earlier identification and risk reduction, we undertook this exploratory pilot study to answer the question, How do healthy women with and without abdominal adiposity differ physiologically and psychosocially?. We recruited a total of 41 women for a single study visit and assessed a battery of baseline physiological and psychological measures. While the women in this study were free of any diagnoses associated with increased CMR, women with increased waist circumference (WC) exhibited significantly altered levels of several measures associated with impending CMR including insulin sensitivity, lipids, and adiponectin as well as lower social support. These findings suggest that a more comprehensive conceptualization of and refinement of measures for CMR may be useful for identifying and reducing CMR and ultimately CVD in women.

Role of AMP-activated protein kinase and adiponectin during development of hepatic steatosis in high-fat diet-induced obesity in rats

Obesity, an abnormal condition of adipose tissue, has recently been recognized as a major cause of metabolic syndromes, especially non-alcoholic fatty liver disease (NAFLD). The aim of the present study was to examine the possible involvement of adipokines in the development of fatty liver. Sprague-Dawley (SD) rats fed a high-fat (HF) diet for 15 weeks developed increased hepatocellular vacuolation, hepatic triglyceride (TG) content and serum TG, total cholesterol and free fatty acid levels, with increases in adipose tissue mass. The serum concentration of adiponectin decreased slightly in these animals. Western blotting analysis demonstrated a decrease in the levels of AMP-activated protein kinase (AMPK) and phosphorylated-AMPK in the livers of these rats. These results indicate similarities between the diet-induced obesity rat model of NAFLD and human NAFLD, thus making the rat a useful model for the further study of NAFLD, including the interactions between adipokines and hepatic fat metabolism.

Shifts in diet from high fat to high carbohydrate improved levels of adipokines and pro-inflammatory cytokines in mice fed a high-fat diet

High-fat diets induce an expansion of the adipose tissue (AT) that can be characterized by chronic low-grade inflammation. AT is an important source of adipokines and pro-inflammatory cytokines. The purpose of this study was to evaluate the effects of a shift from a high-fat diet to high-carbohydrate (CHO) diet on the blood levels of adipokines and pro-inflammation cytokines in mice fed a high-fat diet. Six-week-old male C57BL/6 mice were fed a high-fat diet (40% of the total calories) for 9 weeks to induce obesity, and then the diet was shifted to a high CHO diet (70% of the total calories) for 3 weeks. Body weight and organ weight as well as blood lipid levels were measured. The serum levels of adipokines and pro-inflammatory cytokines were analyzed. Shifting the diet from high fat to high CHO decreased significantly body weight, adipose tissues, and liver weight (p < 0.05). The lipid blood levels (TG, Total-chol, and LDL-chol) decreased. The leptin and resistin blood levels significantly decreased after the diet was shifted to a high-CHO diet (p < 0.05); however, the adiponectin concentrations did not change. The IL-6 levels were also significantly decreased by the high-CHO diet (p < 0.05). The IL-13 serum levels were significantly increased by the high-CHO diet (p < 0.05). Further, the serum levels of the TNF-alpha and supernatant IL-1 beta concentrations in mice fed a high-carbohydrate diet were significantly increased after the mice were shifted to a high-fat diet. On the other hand, the serum IL-4 and supernatant levels did not change. Conclusively, reduction of body weight and adipose tissues through shifts from a high-fat diet to a high-carbohydrate diet effectively improved low-grade inflammation states in mice fed a high-fat diet. Particularly, the reduction of body weight was associated with the levels of leptin, resistin, and IL-6.

Comparison of insulin resistance, metabolic syndrome and adiponectin in overweight bipolar patients taking sodium valproate and controls

OBJECTIVE

Metabolic abnormalities in patients with bipolar disorder may be secondary to obesity, aspects of the disorder or its treatment. To investigate this further, the purpose the present study was to compare insulin resistance, components of the metabolic syndrome and adiponectin levels in a group of overweight bipolar patients taking sodium valproate and a group of non-psychiatric control subjects.

METHODS

Data were collected from 60 overweight bipolar patients who had experienced clinically significant weight gain thought to be related to sodium valproate treatment and from 60 control subjects without psychiatric illness matched for age, gender, body mass index and ethnicity.

RESULTS

The frequency of the metabolic syndrome was high in both groups (50% and 32%, respectively), although not significantly different between groups (p = 0.06). Similar frequencies of insulin resistance (HOMA-IR), abdominal obesity, hypertriglyceridaemia, hypertension and fasting hyperglycaemia were found in both groups. High-density lipoprotein cholesterol levels were lower in patients (p = 0.006), while adiponectin was unexpectedly higher than in control subjects (9.6+/-5.9 microg mL(-1) vs 7.4+/-4.3 microg mL(-1), p = 0.03). The frequencies of insulin resistance (HOMA-IR), the metabolic syndrome and its individual components were not significantly different in patients taking atypical antipsychotic medication and patients not on these medications.

CONCLUSIONS

Frequencies of insulin resistance and the metabolic syndrome were similar in bipolar patients taking sodium valproate and matched control subjects, but dyslipidaemia was more frequent. Adiponectin levels were higher in patients. Further research is required to clarify the reasons for these findings.

Characterization of the transcriptional regulation of the regulator of G protein signaling 2 (RGS2) gene during 3T3-L1 preadipocyte differentiation

Adipocyte differentiation is a complex process involving several signaling pathways. Molecular mechanisms regulating the very early stage of adipocyte differentiation is not fully appreciated yet. Several inducible genes at the early stage of preadipocyte differentiation have been identified, including the regulator of G protein signaling 2 (RGS2), a member of the RGS protein superfamily. This study aimed to clarify the precise induction profile of RGS2 and to determine the essential transcription element(s) regulating RGS2 expression in differentiating 3T3-L1 preadipocytes. RGS2 mRNA expression was elevated immediately at 1 h after differentiation initiation and it remained high until the late stage of differentiation. The putative promoter sequence (approximately 3,000 bp) of the mouse RGS2 gene was isolated and the RGS2 promoter activity was significantly upregulated 3 h after inducing differentiation. The primary signaling pathway leading to RGS2 transcriptional activation appeared to be cAMP-dependent. Sequential deletion and site-directed mutagenesis strategies demonstrate that the RGS2 promoter sequence truncated down to 78 bp in size retained full inducibility by the differentiation stimuli. Mutation of a Sp1 site within the 78 bp region significantly blocked promoter activity. In addition, high expression of Sp1 transcription factor was noted prior to and paralleling the differentiation process. Taken together, our data suggest that RGS2 transcription is immediately induced via a cAMP-dependent pathway after initiation of 3T3-L1 differentiation and the RGS2 mRNA level remains consistently high throughout the differentiation progression. A Sp1 site within RGS2 promoter appeared to be a crucial response element to regulate RGS2 transcription.

Grape-seed procyanidins prevent low-grade inflammation by modulating cytokine expression in rats fed a high-fat diet

OBJECTIVE

The main objective of this study was to evaluate the effect of procyanidin intake on the level of inflammatory mediators in rats fed a hyperlipidic diet, which are a model of low-grade inflammation as they show an altered cytokine production.

DESIGN

Male Zucker Fa/fa rats were randomly grouped to receive a low-fat (LF) diet, a high-fat (HF) diet or a high-fat diet supplemented with procyanidins from grape seed (HFPE) (3.45 mg/kg feed) for 19 weeks and were then euthanized. We determined biochemical parameters, C-reactive protein (CRP) and IL-6 levels in plasma. Adipose tissue depots and body weight were also determined. We assessed CRP, IL-6, TNF-alpha and adiponectin gene expression in liver and white adipose tissue (WAT).

RESULTS

As expected, rats fed the HF diet show an enhanced production of CRP. Our results demonstrate that the HFPE diet decreases rat plasma CRP levels but not IL-6 levels. The decrease in plasma CRP in HFPE rats is related to a down-regulation of CRP mRNA expression in the liver and mesenteric WAT. We have also shown a decrease in the expression of the proinflammatory cytokines TNF-alpha and IL-6 in the mesenteric WAT. In contrast, adiponectin mRNA is increased in this tissue due to the procyanidin treatment. As previously reported, CRP plasma levels correlate positively with its expression in the mesenteric WAT, suggesting that procyanidin extract (PE) modulates CRP at the synthesis level. CRP plasma levels also correlate positively with body weight. As expected, body weight is associated with the adiposity index. Also, TNF-alpha expression and IL-6 expression have a strong positive correlation. In contrast, the expression of the anti-inflammatory cytokine adiponectin correlates negatively with the expression of TNF-alpha and IL-6 in the mesenteric WAT.

CONCLUSION

These results suggest a beneficial effect of PE on low-grade inflammatory diseases, which may be associated with the inhibition of the proinflammatory molecules CRP, IL-6 and TNF-alpha and the enhanced production of the anti-inflammatory cytokine adiponectin. These findings provide a strong impetus to explore the effects of dietary polyphenols in reducing obesity-related adipokine dysregulation to manage cardiovascular and metabolic risk factors.

Serum adipocyte fatty acid binding protein as a new biomarker predicting the development of type 2 diabetes: a 10-year prospective study in a Chinese cohort

OBJECTIVE

Adipocyte fatty acid-binding protein (A-FABP) is abundantly expressed in adipocytes and plays a role in glucose homeostasis in experimental animals. We have previously shown that circulating A-FABP levels are associated with the metabolic syndrome, which confers an increased risk of type 2 diabetes. Here we investigated whether serum A-FABP levels could predict the development of diabetes in a 10-year prospective study.

RESEARCH DESIGN AND METHODS

Baseline serum A-FABP levels were measured with an enzyme-linked immunosorbent assay in 544 nondiabetic subjects, recruited from the Hong Kong Cardiovascular Risk Factor Prevalence Study cohort, who were followed prospectively to assess the development of type 2 diabetes. The role of A-FABP in predicting the development of type 2 diabetes over 10 years was investigated using Cox regression analysis.

RESULTS

At baseline, serum sex-adjusted A-FABP levels were higher in subjects with impaired glucose tolerance (IGT) or impaired fasting glucose (IFG) (P < 0.00001 versus normal glucose tolerance) and correlated positively with adverse cardiometabolic risk factors. Over 10 years, 96 subjects had developed type 2 diabetes. High baseline A-FABP was predictive of type 2 diabetes, independent of obesity, insulin resistance, or glycemic indexes (relative risk [RR] 2.25 [95% CI 1.40-3.65]; P = 0.001; above versus below sex-specific median). High A-FABP levels remained an independent predictor of type 2 diabetes in the high-risk IGT/IFG subgroup (adjusted RR 1.87 [1.12-3.15]; P = 0.018).

CONCLUSIONS

Serum A-FABP was associated with glucose dysregulation and predicted the development of type 2 diabetes in a Chinese cohort.

Serum adipokines are associated with cholesterol metabolism in the metabolic syndrome

BACKGROUND

The purpose of this study was to investigate whether cholesterol metabolism is associated with serum adipokines and inflammatory markers.

METHODS

In fifty-eight subjects with impaired fasting glucose or impaired glucose tolerance and features of the metabolic syndrome cholesterol metabolism was assayed with serum non-cholesterol sterol ratios to cholesterol, surrogate markers of synthesis (cholesterol precursors) and dietary absorption % of cholesterol (cholestanol and plant sterols) and related them to serum adiponectin, leptin, high-sensitive C-reactive protein (hs-CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha).

RESULTS

Adiponectin was negatively related to synthesis markers (e.g. desmosterol r=-0.371, P<0.01), and positively to absorption markers (e.g. cholestanol r=0.269, P<0.05). Leptin was associated with synthesis markers (e.g. desmosterol r=0.271, P<0.05) and negatively with absorption markers (e.g. sitosterol r=-0.278, P<0.05). Hs-CRP was negatively associated with absorption markers (e.g. sitosterol r=-0.407, P<0.001). IL-6 and TNF-alpha were not related to cholesterol metabolism. When dividing the subjects into tertiles by the serum desmosterol/cholestanol ratio, the I tertile (high synthesis/low absorption) was associated with low adiponectin concentrations, high BMI and serum leptin concentrations (P<0.05 for all).

CONCLUSIONS

Adiponectin, leptin and hs-CRP were associated with variables of cholesterol metabolism. A high ratio of cholesterol synthesis to absorption is characterized by high serum leptin and low adiponectin concentrations.