Inflammation, insulin resistance, and obesity

Folic Acid Supplementation Improves Glycemic Control for Diabetes Prevention and Management: A Systematic Review and Dose-Response Meta-Analysis of Randomized Controlled Trials

Background: There is a growing interest in the considerable benefits of dietary supplementations, such as folic acid, on the glycemic profile. We aimed to investigate the effects of folic acid supplementation on glycemic control markers in adults. Methods: Randomized controlled trials examining the effects of folic acid supplementation on glycemic control markers published up to March 2021 were detected by searching online databases, including Scopus, PubMed, Embase, and ISI web of science, using a combination of related keywords. Mean change and standard deviation (SD) of the outcome measures were used to estimate the mean difference between the intervention and control groups at follow-up. Meta-regression and non-linear dose-response analysis were conducted to evaluate the association between pooled effect size and folic acid dosage (mg/day) and duration of the intervention (week). From 1814 detected studies, twenty-four studies reported fasting blood glucose (FBG), fasting insulin, hemoglobin A1C (HbA1C), and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) as an outcome measure. Results: Results revealed significant reductions in FBG (weighted mean difference (WMD): −2.17 mg/dL, 95% CI: −3.69, −0.65, p = 0.005), fasting insulin (WMD: −1.63 pmol/L, 95% CI: −2.53, −0.73, p < 0.001), and HOMA-IR (WMD: −0.40, 95% CI: −0.70, −0.09, p = 0.011) following folic acid supplementation. No significant effect was detected for HbA1C (WMD: −0.27%, 95% CI: −0.73, 0.18, p = 0.246). The dose-response analysis showed that folic acid supplementation significantly changed HOMA-IR (r = −1.30, p-nonlinearity = 0.045) in non-linear fashion. However, meta-regression analysis did not indicate a linear relationship between dose, duration, and absolute changes in FBG, HOMA-IR, and fasting insulin concentrations. Conclusions: Folic acid supplementation significantly reduces some markers of glycemic control in adults. These reductions were small, which may limit clinical applications for adults with type II diabetes. Further research is necessary to confirm our findings.

Integrated transcriptome and proteome analysis reveals potential mechanisms for differential abdominal fat deposition between divergently selected chicken lines

Genetic selection for meat production performance of broilers concomitantly causes excessive abdominal fat deposition, accompanied by several adverse effects, such as the reduction of feed conversion efficiency and reproduction performance. Our previous studies have identified important genes regulating chicken fat deposition, using the Northeast Agricultural University broiler lines divergently selected for abdominal fat content (NEAUHLF) as an animal model. However, the molecular mechanism underlying fat deposition differences between fat and lean broilers remains largely unknown. Here, we integrated the transcriptome (RNA-Seq) and quantitative proteome (isobaric tags for relative and absolute quantitation, iTRAQ) profiling analyses on abdominal fat tissues from NEAUHLF chicken lines. Differentially expressed genes (2167 DEGs, corrected p-value < 0.01) and differentially abundant proteins (199 DAPs, corrected p-value < 0.05) were identified in lean line compared to fat line. Down-regulated DEGs and DAPs mainly enriched in pathways related to fatty acid metabolism, fatty acid biosynthesis, and PPAR signaling, and interestingly, up-regulated DEGs and DAPs enriched both in lysosome pathway. Moreover, numerous key DEGs and DAPs involved in long-chain fatty acid uptake, in situ lipogenesis (fatty acid and cholesterol synthesis), and lipid droplet accumulation were discovered after integrated transcriptome and proteome analysis. SIGNIFICANCE: Excessive abdominal fat deposition critically affects the health of broilers and causes economic loss to broiler producers, but the molecular mechanism of abdominal fat deposition is still unclear in chicken. We identified key DEGs/DAPs and potential pathways through an integration of chicken abdominal fat tissues transcriptome and proteome analyses. Our findings will facilitate a better revealing the mechanism and provide a novel insight into abdominal fat content discrepancy between the fat and lean chicken lines.

Effect of Calorie Restriction and Exercise on Type 2 Diabetes

Type-2 diabetes (T2D) is a chronic condition, generally regarded as an irreversible, that is among the top 10 causes of death globally. The hallmark of T2D is hyperglycemia, which results from disturbances in insulin sensitivity, insulin secretion, β-cell dysfunction and insulin resistance. Several clinical and lifestyle factors are involved in the progression of T2D, such as obesity and physical inactivity. A high-calorie diet is the main contributor to the development of obesity, which results in T2D, as obesity or increased intra-abdominal adipose tissue is related to insulin resistance. Technological advances have contributed to individuals having a more sedentary lifestyle, leading to obesity and T2D. T2D can be treated with lifestyle interventions, such as diet and exercise. Herein, we highlight the positive impact of a very low-calorie diet (VLCD) and lifestyle modalities in the treatment and prevention of T2D. An inclusion of VLCD 400-800 kcal/day for 8 weeks and ≥ 150 minutes exercise 5 times a week as lifestyle interventions can decrease glucose levels to normal, reduce HbA1c and improve insulin resistance and sensitivity. Therefore, a potential mechanism in maintaining glucose homeostasis and remission of T2D by VLCD and exercise reduces body weight.

A Retrospective Analysis of the Impact of Bariatric Surgery on the Management of Chronic Migraine

PURPOSE

To investigate the association of the two most common bariatric surgical procedures, vertical sleeve gastrectomy (VSG) and Roux-en-Y gastric bypass (RYGB), with sustained remission from chronic migraine.

MATERIALS AND METHODS

Using IBM MarketScan® research database to examine inpatient and pharmacy claims from 2010 through 2017. A cohort of bariatric patients with chronic migraine was created using inclusion and exclusion criteria. Remission was defined as no refill of first-line migraine medication for 180 days after a patients' medication was expected to run out, and recurrence as medication refill after at least 180 days of remission.

RESULTS

Of 1680 patients in our cohort, 931 (55.4%) experienced remission of migraine. Of these, 462 (49.6%) had undergone VSG, while 469 (50.4%) had undergone RYGB. Patients who underwent RYGB had an 11% (RR = 1.11, 95% CI: 1.05, 1.17) increase in likelihood of remission of migraine and a 20% (RR = 0.80, 95% CI: 0.63, 1.04) decrease in likelihood of recurrence of migraine compared to patients who underwent VSG. Older age group, higher number of medications at time of surgery, and female sex were associated with a decreased likelihood of remission.

CONCLUSION

Type of bariatric procedure, age, number of medications at surgery, and sex were the most important predictors of migraine remission after surgery.

Vascular Cells Proteome Associated with Bradykinin and Leptin Inflammation and Oxidative Stress Signals

Among the primary contributors to cardiovascular diseases are inflammation and oxidative imbalance within the vessel walls as well as the fibrosis of rat aortic smooth muscle cell (RASMC). Bradykinin (BK) and leptin are inflammatory modulators that are linked to vascular injury. In this study, we employed tandem LC-MS/MS to identify protein signatures that encompass protein abundance in RASMC treated with BK or leptin followed by systems biology analyses to gain insight into the biological pathways and processes linked to vascular remodeling. In the study, 1837 proteins were identified in control untreated RASMC. BK altered the expression of 72 (4%) and 120 (6.5%) proteins, whereas leptin altered the expression of 189 (10.2%) and 127 (6.5%) proteins after 24 and 48 h, respectively, compared to control RASMC. BK increased the protein abundance of leptin receptor, transforming growth factor-β. On the other hand, leptin increased the protein abundance of plasminogen activator inhibitor 1 but decreased the protein abundance of cofilin. BK and leptin induced the expression of inflammatory cytokines such as tumor necrosis factor alpha (TNF-α) and interleukin-1β (IL-1β) and pathway analysis revealed the activation of mitogen-activated protein kinases (MAPKs) and AKT pathways. The proteome profile in response to BK and leptin revealed mechanistic interplay of multiple processes that modulate inflammation and oxidative stress signals in the vasculature.

Multiple Points Change in the Association of Blood Pressure Subtypes with Anthropometric Indices of Adiposity among Children in a Rural Population

BACKGROUND

Hypertension has gained global significance and risk of cardiovascular disease, and adiposity is the most important of the conditions associated with and considered responsible for hypertension in children. Therefore, the present study aimed to determine whether indices of adiposity independently predicted blood pressure at multiple points in gender-specific groups.

METHODS

This was a cross-sectional study involving 10 randomly selected primary schools within the Ellisras Longitudinal Study, and involved 1816 adolescents (876 girls and 940 boys) aged 8 to 17 years. All the anthropometric indices and blood pressures (BP) were examined according to the International Society for the Advancement of Kinanthropometry protocol.

RESULTS

In an adjusted linear quantile regression analysis of boys, waist circumference (WC) was associated with BP across all multiple points of systolic blood pressure (SBP). Furthermore, the triceps skinfold site was associated with high SBP. In girls, body mass index (BMI) was significantly associated with SBP after adjustment for potential confounders. Other anthropometric indices of adiposity, including WC, biceps, and triceps skinfold sites were not associated with SBP.

CONCLUSIONS

The results of the present study suggest that in black South African children, variables such as WC and triceps skinfold site may provide stronger explanatory capacity to SBP variance and systolic hypertension risk in boys than other adiposity indices; whereas in girls, only WC and BMI predict diastolic blood pressure (DBP) and SBP, respectively.

Salusin-α levels are negatively correlated with diastolic blood pressure in children with obesity

Salusins have emerged as a new biomarker that reflects an increased inflammatory state, which is associated with cardiovascular risk. We investigated the predictive value and usefulness of salusins as an inflammatory biomarker in obese children. This prospective cohort study included 75 obese children and 101 healthy children (as a control group). Salusin-α, Salusin-β, and various cardiovascular parameters were assessed in both groups. Correlation analyses of Salusin-α and Salusin-β with body mass index standard deviation scores and inflammatory and cardiovascular markers were performed. The mean patient age was 11.9±2.4 years for the obese group and 12.5±2.1 years for the control group. The obese children had a significantly higher heart rate, systolic blood pressure, diastolic blood pressure, epicardial adipose tissue thickness, and left ventricular mass than did the children in the control group. There was no significant correlation between Salusin-α and Salusin-β and body mass index; however, there was a negative correlation between Salusin- α and diastolic blood pressure (r = 0.277, p = 0.004). Overall, there was no significant difference in the Salusin-α and Salusin-β levels between obese and healthy children. However, a negative correlation was found between Salusin-α and diastolic blood pressure. Although this result suggests that Salusin-α might be an early marker of cardiovascular involvement in obese children, further studies are needed to demonstrate the predictive value of salusins.

Investigation of galectin-3, lipocalin 2, retinol binding protein (RBP), small dense low-density lipoprotein (sdLDL) in patients with hirsutism

Introduction

Hirsutism is defined as excessive terminal hair in androgen-dependent areas in women. Adipose tissue is no longer regarded as a storage site for triglycerides or as a source of free fatty acids but is currently emerging as a key constituent of energy metabolism secreting numerous enzymes, cytokines, growth factors, and hormones.

Aim

To evaluate serum levels of galectin-3 (Gal3), lipocalin-2 (LCN2), retinol binding protein (RBP), and small dense low-density lipoprotein (sdLDL) in patients with hirsutism and patients co-presenting with polycystic ovary syndrome (PCOS) and hirsutism.

Material and methods

The study included 90 patients that were divided into three groups: (I) patients with idiopathic hirsutism (IH) (n = 30), (II) PCOS patients with hirsutism (H-PCOS) (n = 30), and (III) the control group (n = 30). Informed consent was obtained from each participant. Idiopathic hirsutism was scored using the modified Ferriman-Gallwey (mFG) scoring system and the diagnosis of PCOS was established based on the modified Rotterdam criteria. Human Gal3, LCN2, RBP, and sdLDL levels were analysed using a commercially available double-antigen sandwich enzyme-linked immunosorbent assay.

Results

No significant difference was found between the three groups with regard to serum Gal3, LCN2, RBP, and sdLDL levels (p > 0.05). Median values were higher in the H-PCOS group than in the other two groups: body weight (median: 76.5 kg) (p < 0.001), waist circumference (median: 82.5 cm) (p = 0.001).

Conclusions

No significant correlation was found between the adipokines that play a role in the aetiology of numerous diseases and some mediators of the lipid metabolism and hirsutism.

Afamin: an early predictor of preeclampsia

Purpose

Oxidative stress is involved in the pathogenesis of hypertensive disorders such as preeclampsia (PE) and associated with the human vitamin E-binding protein afamin. The aim of this study was, therefore, to analyse afamin in the first trimester of patients developing PE later in pregnancy and in control subjects without pregnancy complications.

Methods

In this retrospective study, 137 serum samples from the first trimester of pregnancy were analysed in a case–control study design. 39 patients developed PE (10 patients with early-onset and 29 patients with late onset disease) and 98 women had an uncomplicated pregnancy. Mann–Whitney U test, t test, logistic regression and ROC analyses were performed for statistical evaluation.

Results

Pregnant women developing PE presented with higher afamin concentrations in the first trimester [median 101.81 mg/L; interquartile range (IQR) 88.94–113.26] compared to subjects with uncomplicated pregnancy (median 86.40; IQR 75.26–96.92; p < 0.001). After adjusting for confounders, the odds ratio per afamin standard deviation was 1.60 (95% CI: 1.04–2.58; p = 0.04). An afamin threshold concentration of 87.8 mg/L exhibited the best sensitivity (79.5%) and specificity (57.1%) in predicting PE. Subgroup analysis of early- and late-onset disease resulted in substantially higher afamin concentrations in women with developing late-onset PE compared to controls (p < 0.001) with an odds ratio per afamin standard deviation of 1.62 (95% CI: 0.98–2.70; p = 0.06).

Conclusions

Serum afamin concentrations are elevated in the first trimester among patients developing PE compared to controls. Substantial differences were observed mainly among patients with late-onset PE.

N1-methylnicotinamide (MNAM) as a guardian of cardiovascular system

Atherosclerosis is identified as the formation of atherosclerotic plaques, which could initiate the formation of a blood clot in which its growth to coronary artery can lead to a heart attack. N-methyltransferase (NNMT) is an enzyme that converts the NAM (nicotinamide) to its methylated form, N1-methylnicotinamide (MNAM). Higher levels of MNAM have been reported in cases with coronary artery disease (CAD). Further, MNAM increases endothelial prostacyclin (PGI2) and nitric oxide (NO) and thereby causes vasorelaxation. The vasoprotective, anti-inflammatory and anti-thrombotic roles of MNAM have been well documented; however, the exact underlying mechanisms remain to be clarified. Due to potential role of MNAM in the formation of lipid droplets (LDs), it might exert its function in coordination with lipids, and their targets. In this study, we summarized the roles of MNAM in cardiovascular system and highlighted its possible mode of actions.

Dietary Flavonoids in the Prevention of T2D: An Overview

Type 2 diabetes (T2D) is a progressive metabolic disease that is increasing in prevalence globally. It is well established that insulin resistance (IR) and a progressive decline in functional β-cell mass are hallmarks of developing T2D. Obesity is a leading pathogenic factor for developing IR. Constant IR will progress to T2D when β-cells are unable to secret adequate amounts of insulin to compensate for decreased insulin sensitivity. Recently, a considerable amount of research has been devoted to identifying naturally occurring anti-diabetic compounds that are abundant in certain types of foods. Flavonoids are a group of polyphenols that have drawn great interest for their various health benefits. Results from many clinical and animal studies demonstrate that dietary intake of flavonoids might be helpful in preventing T2D, although cellular and molecular mechanisms underlying these effects are still not completely understood. This review discusses our current understanding of the pathophysiology of T2D and highlights the potential anti-diabetic effects of flavonoids and mechanisms of their actions.

Down regulation of Peroxiredoxin-3 in 3T3-L1 adipocytes leads to oxidation of Rictor in the mammalian-target of rapamycin complex 2 (mTORC2)

Mitochondrially-derived oxidative stress has been implicated in the development of obesity-induced insulin resistance and is correlated with down regulation of Peroxiredoxin-3 (Prdx3). Prdx3 knockout mice exhibit whole-body insulin resistance, while Prdx3 transgenic animals remain insulin sensitive when placed on a high fat diet. To define the molecular events linking mitochondrial oxidative stress to insulin action, Prdx3 was silenced in 3T3-L1 adipocytes (Prdx3 KD) and the resultant cells evaluated for mitochondrial function, endoplasmic reticulum stress (ER stress), mitochondrial unfolded protein response (mtUPR) and insulin signaling. Prdx3 KD cells exhibit a two-fold increase in H₂O₂, reduced insulin-stimulated glucose transport and attenuated S⁴⁷³ phosphorylation of the mTORC2 substrate, Akt. Importantly, the decrease in glucose uptake can be rescued by pre-treatment with the antioxidant N-acetyl-cysteine (NAC). The changes in insulin sensitivity occur independently from activation of the ER stress or mtUPR pathways. Analysis of mTORC2, the complex responsible for phosphorylating Akt at S⁴⁷³, reveals increased cysteine oxidation of Rictor in Prdx3 KD cells that can be rescued with NAC. Taken together, these data suggest mitochondrial dysfunction in adipocytes may attenuate insulin signaling via oxidation of the mammalian-target of rapamycin complex 2 (mTORC2).

Toll-Like Receptor Function in Acute Wounds

Significance: Inflammation is an integral part of immune response and supports optimal wound healing in adults. Inflammatory cells such as neutrophils, macrophages, dendritic cells, lymphocytes, and mast cells produce important cytokines, chemokines, and growth factors. These immune cells interact with keratinocytes, fibroblasts, and endothelial cells (ECs), as well as the extracellular matrix within a complicated network that promotes and regulates wound healing. Aberrant and persistent inflammation may result in delayed wound healing, scar formation, or chronic wounds. Targeting the molecules involved in the inflammatory response may have great potential therapeutic value. Recent Advances and Critical Issues: Toll-like receptors (TLRs) are pattern recognition receptors that recognize pathogen-associated molecular patterns from microbes or danger-associated molecular patterns from damaged cells. The discovery of TLRs sheds new light on the mechanism by which the inflammatory or innate immune response is initiated in wound healing. Convincing evidence now shows that multiple types of cells, including infiltrating or resident inflammatory cells, keratinocytes, fibroblasts, and ECs, express specific types of TLRs. Experimental reduction of certain TLRs or treatment of wounds with TLR ligands has been shown to affect wound healing. A better understanding of the involvement of TLRs in the innate immune response during skin wound healing may suggest novel strategies to improve the quality of tissue repair. Future Directions: Despite the indisputable role of TLRs in regulating the immune response in acute wound healing, the functions of TLRs that are relevant to human wound healing and chronic wounds are poorly understood.

Resistin increases the expression of NOD2 in mouse monocytes

Previous studies have indicated that resistin, a type of adipokine, contributes to the development of insulin resistance and type 2 diabetes mellitus, and mediates inflammatory reactions. However, a specific receptor for resistin has not yet been identified. In this study, the relationship between resistin and nucleotide-binding oligomerization domain-like receptors, as well as resistin signal transduction, was examined through transfection, quantitative polymerase chain reaction, western blot analysis and ELISA. The mRNA expression of nucleotide-binding oligomerization domain-containing protein 2 (NOD2), a key immune receptor related to insulin resistance, was significantly increased by resistin treatment at concentrations of 100, 150 and 200 ng/ml (P<0.05, P<0.01 and P<0.01, respectively). The mRNA expression of downstream signaling molecules in the NOD2 signaling pathway, receptor-interacting serine/threonine-protein kinase 2 (RIP2; P<0.01 at 6, 12 and 24 h) and inhibitor of NF-κB kinase subunit beta (P<0.01 at 3, 6, 12 and 24 h) were significantly increased by resistin treatment compared with the control. The mRNA expression of key proinflammatory cytokines, tumor necrosis factor α, IL (interleukin)-6 and IL-1β, were also significantly increased by resistin treatment compared with the control (P<0.01). NOD2 knockdown by small interfering RNA (siRNA) significantly decreased the expression of NOD2 and RIP2 (P<0.01), and there was no significant increase in the levels of cytokines, as compared with treatment with control siRNA. These findings indicate that the inflammatory reaction induced by resistin involves the NOD2-nuclear factor (NF)-κB signaling pathway. The inhibition of NF-κB significantly decreased the secretion of key inflammatory cytokines (P<0.01), suggesting that NF-κB signaling mechanisms are essential to the resistin-induced inflammatory response.

Pathophysiological Role of Adiponectin, Leptin and Asymmetric Dimethylarginine in the Process of Atherosclerosis

Adipose tissue is recognized as a rich source of proinflammatory mediators that may directly contribute to vascular injury, insulin resistance, and atherogenesis. Many studies have shown that adiponectin has antiatherogenic and anti-inflammatory properties. Adiponectin acts not only as a factor increasing insulin sensitivity, and the protective effect may result from its ability to suppress production of proinflammatory cytokines. It negatively regulates the expression of TNF-alpha and C-reactive protein (CRP) in adipose tissue; reduces expression of vascular and intracellular adhesion molecules (VCAM-1, ICAM-1), E-selectin, interleukin-8 (IL-8). Hyperleptinemia has been linked with the development of hypertension and endothelial dysfunction/atherosclerosis, two main pathophysiological conditions associated with cardiovascular disease development. Leptin-mediated increases in sympathetic nervous system activity may be among the principal mechanisms evoking obesity related hypertension. Leptin stimulates the secretion of proinflammatory cytokines, and increases the release of endothelin-1 (ET-1), which may promote hypertension. Increased serum levels of asymmetric dimethylarginine (ADMA), a physiological regulator of the biosynthesis of nitric oxide (NO), promote the process of atherosclerosis, leading to the occurrence of endothelial dysfunction and cardiovascular disease.

Carotid intima media thickness in obese children: is there an association with hyperlipidemia?

BACKGROUND

We aimed to evaluate the association between hyperlipidemia and carotid intima media thickness in obese children, compared to non-obese ones.

METHODS

Two hundred (110 girls, 90 boys) children aged between 6 and 15 years participated in this study. The obese group included 53 girls, 47 boys whose body mass indices (BMI) above 95th percentile, the control group included 57 girls, 43 boys who had normal weight. Fasting total cholesterol, triglyceride, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) levels were measured. Carotid intima media thickness (cIMT) was performed with neck ultrasound.

RESULTS

The median thickness of right, left and mean carotis intima media were statistically higher in the study group, compared to the control group. The mean cholesterol, triglyceride, HDL-C, LDL-C levels of the study group were statistically higher, compared to the control group. There was no relationship between BMI and left carotis intima media thickness, but there was statistically significant relationship between BMI and right, mean cIMTs in the study group. There was no correlation between serum lipid levels and cIMTs in the study group. The mean atherogenic index of the study group was statistically higher, compared to the control group. There was no statistical correlation between atherogenic index and cIMTs in both of the groups.

CONCLUSIONS

We observed that obese children had higher carotis intima media thicknesses. Carotis intima media thickness related to obesity can play an important role in future pre-atherosclerotic changes. Large population based studies are required to confirm this associaton.

Metabolic syndrome, platelet activation and the development of transient ischemic attack or thromboembolic stroke

Stroke is the second most common cause of mortality in the world today, where transient ischemic attack (TIA) is a period of focal ischemia, the symptoms of which resemble a thromboembolic stroke. Contrary to stroke, TIA symptoms typically last less than one hour and necrosis is absent. Stroke is often preceded by TIA, making it an important predictor of future ischemic events. The causal role of atherosclerosis in the development of TIA is well established, however, research indicates that the atherosclerotic process begins years earlier with the development of metabolic syndrome, which affects approximately 45% of the adult population worldwide. Metabolic syndrome is present if three or more of the following is present: increased waist circumference, increased triglycerides, decreased HDL, increased fasting glucose and hypertension. This syndrome causes systemic inflammation that activates the coagulation system and may cause the formation of pathological thrombi. The role of platelets in stroke has been studied and platelet activation pathways identified. ADP and thromboxane A(2) are the most common activators of platelets in normal physiology. Several pharmacological treatments have been employed to prevent the activation of platelets, the most common of which include aspirin and P2Y(12)-inhibitors. Although treatment is administered strokes and subsequent TIAs are very common in individuals that suffered an initial event. This indicates that research needs to be done in order to elucidate new therapeutic targets, but also to better treat ischemic events to not only decrease the amount of recurring events but also decrease stroke mortality worldwide.

Effects of body weight reduction on plasma leptin and adiponectin/leptin ratio in obese patients with type 1 diabetes mellitus

The aim of this study was to explore the changes in the adipokines leptin and adiponectin in obese patients with type 1 diabetes mellitus (T1DM) who underwent seven days of fasting and 21 days of low-calorie diet (LCD). The plasma leptin and adiponectin concentrations were measured in 14 obese patients with T1DM at baseline, immediately after 7 days of fasting, and after 21 days of LCD. 13 non-obese patients with T1DM were studied only after an overnight fasting. Bioimpedance technique was used for determination of body composition. Obese T1DM patients lost 6.0 kg (6.0; 6.8) (median, 25 %; 75 %) and decreased their fat tissue after fasting and LCD. Plasma leptin in obese T1DM was significantly higher than in non-obese T1DM patients: 9.10 (5.06; 25.89) vs. 1.71 (1.12; 7.08) microg . l(-1) and transiently decreased immediately after fasting: 3.45 microg . l(-1) (1.47; 7.00), (P<0.05). Adiponectin/leptin ratio in obese T1DM was significantly lower than in non-obese T1DM patients: 0.67 (0.57; 1.49) vs. 3.50 (2.46; 6.30) . 10(3) and transiently increased immediately after fasting: 2.22 (1.26; 3.24) . 10(3), (P<0.05). We conclude that obese patients with T1DM are characterized by hyperleptinemia that is reduced by prolonged fasting, but only slightly affected by low calorie diet.

Mechanism and clinical evidence of lipocalin-2 and adipocyte fatty acid-binding protein linking obesity and atherosclerosis

Obesity is considered to be a chronic inflammatory state in which the dysfunction of adipose tissue plays a central role. The adipokines, which are cytokines secreted by adipose tissue, are key links between obesity and related diseases such as metabolic syndrome and atherosclerosis. LCN2 and A-FABP, both of which are major adipokines predominantly produced in adipose tissue, have recently been shown to be pivotal modulators of vascular function. However, different adipokines modulate the development of atherosclerosis in distinctive manners, which are partly attributable to their unique regulatory mechanisms and functions. This review highlights recent advances in the understanding of the role of two adipokines in mediating chronic inflammation and the pathogenesis of atherosclerosis.

High-fat diet induces changes in adipose tissue trans-4-oxo-2-nonenal and trans-4-hydroxy-2-nonenal levels in a depot-specific manner

Protein carbonylation is the covalent modification of proteins by α,β-unsaturated aldehydes produced by nonenzymatic lipid peroxidation of polyunsaturated fatty acids. The most widely studied aldehyde product of lipid peroxidation, trans-4-hydroxy-2-nonenal (4-HNE), is associated with obesity-induced metabolic dysfunction and has demonstrated reactivity toward key proteins involved in cellular function. However, 4-HNE is only one of many lipid peroxidation products and the lipid aldehyde profile in adipose tissue has not been characterized. To further understand the role of oxidative stress in obesity-induced metabolic dysfunction, a novel LC-MS/MS method was developed to evaluate aldehyde products of lipid peroxidation and applied to the analysis of adipose tissue. 4-HNE and trans-4-oxo-2-nonenal (4-ONE) were the most abundant aldehydes present in adipose tissue. In high fat-fed C57Bl/6J and ob/ob mice the levels of lipid peroxidation products were increased 5- to 11-fold in epididymal adipose, unchanged in brown adipose, but decreased in subcutaneous adipose tissue. Epididymal adipose tissue of high fat-fed mice also exhibited increased levels of proteins modified by 4-HNE and 4-ONE, whereas subcutaneous adipose tissue levels of these modifications were decreased. High fat feeding of C57Bl/6J mice resulted in decreased expression of a number of genes linked to antioxidant biology selectively in epididymal adipose tissue. Moreover, TNFα treatment of 3T3-L1 adipocytes resulted in decreased expression of GSTA4, GPx4, and Prdx3 while upregulating the expression of SOD2. These results suggest that inflammatory cytokines selectively downregulate antioxidant gene expression in visceral adipose tissue, resulting in elevated lipid aldehydes and increased protein carbonylation.

Effects of martial arts exercise on body composition, serum biomarkers and quality of life in overweight/obese premenopausal women: a pilot study

Various exercise interventions have been shown to benefit weight control and general health in different populations. However, very few studies have been conducted on martial arts exercise (MAE). The objective of this pilot study is to evaluate the efficacy of 12 weeks of MAE intervention on body composition, serum biomarkers and quality of life (QOL) in overweight/obese premenopausal women. We found that subjects in the MAE group did not lose body weight, while they significantly decreased fat-free mass and muscle mass as compared to those in the control group, who demonstrated an increase in these parameters. The MAE group demonstrated an increase in serum IGF-I concentration, but no change in others. MAE may be a feasible and effective approach to improve body composition and QOL in overweight/obese premenopausal women. Our study underscores the need for further studies using larger samples to establish possible benefits of MAE in various populations.

Inflammation triggers high mobility group box 1 (HMGB1) secretion in adipose tissue, a potential link to obesity

BACKGROUND

Low grade inflammation is one of the major metabolic disorders in case of obesity due to variable secretion of adipose derived cytokines called adipokines. Recently the nuclear protein HMGB1 was identified as an inflammatory alarmin in obesity associated diseases. However HMGB1 role in adipose tissue inflammation is not yet studied.

OBJECTIVES

The aim of this study was to prove the expression of HMGB1 in human adipose tissue and to assess the levels of expression between normo-weight and obese individuals. Furthermore we determined which type of cells within adipose tissue is involved in HMGB1 production under inflammatory signal.

METHODS

Western-blot was performed on protein lysates from human normo-weight and obese adipose tissue to study the differential HMGB1 expression. Human normo-weight adipose tissue, adipose-derived stromal cells (ASCs) and adipocytes were cultured and stimulated with LPS to induce inflammation. HMGB1, IL-6 and MCP-1 secretion and gene expression were quantified by ELISA and Q-PCR respectively, as well as cell death by LDH assay. HMGB1 translocation during inflammation was tracked down by immunofluorescence in ASCs.

RESULTS

HMGB1 was expressed 2-fold more in adipose tissue from obese compared to normo-weight individuals. LPS led to an up-regulation in HMGB1 secretion and gene expression in ASCs, while no change was noticed in adipocytes. Moreover, this HMGB1 release was not attributable to any cell death. In LPS-stimulated ASCs, HMGB1 translocation from nucleus to cytoplasm was detectable at 12h and the nuclear HMGB1 was completely drained out after 24h of treatment.

CONCLUSION

The expression level studies between adipose tissue from normo-weight and obese individuals together with in vitro results strongly suggest that adipose tissue secretes HMGB1 in response to inflammatory signals which characterized obesity.

Serum retinol-binding protein 4 is independently associated with pediatric NAFLD and fasting triglyceride level

OBJECTIVES

Nonalcoholic fatty liver disease (NAFLD) is identified as a major liver disease in children. The present study aimed to identify the prevalence and predictors of pediatric NAFLD and the correlation between serum retinol-binding protein 4 (RBP4) levels and metabolic characteristics in children.

METHODS

A total of 748 schoolchildren, ages 6 to 12 years, were enrolled in 2009. The body weight and height were measured in the morning before intake. Laboratory tests included overnight fasting serum lipids, insulin, liver enzymes, and RBP4 levels. Hepatic steatosis was determined by ultrasound in 219 volunteers.

RESULTS

The rates of NAFLD were 3% in the normal-weight, 25% in the overweight, and 76% in the obese children. Twenty (22%) of obese children had abnormal alanine aminotransferase (ALT) levels. In children with NAFLD, younger age and higher body mass index (BMI), insulin/homeostasis model of assessment, and male sex rate were associated with abnormal liver function. Stepwise increments in BMI, insulin, homeostasis model of assessment, and ALT were found in children with normal livers to simple steatosis, and to steatosis with abnormal ALT. Multiple logistic regression analysis confirmed that serum RBP4 levels (P = 0.048), ALT (P = 0.048), and BMI (P < 0.001) were independently predictors of pediatric NAFLD. Moreover, multiple linear regression analysis revealed that only serum triglycerides levels were positively related to RBP4 levels (P < 0.001).

CONCLUSIONS

Higher RBP4 and ALT levels as well as BMI are independently associated with pediatric NAFLD in Taiwan. In addition, an increment in RBP4 levels was positively correlated to hypertriglyceridemia in children.

NOD1 activation induces innate immune responses and insulin resistance in human adipocytes

AIMS

The innate immune-receptor nucleotide oligomerization domain (NOD) protein recognizes intracellular bacterial peptidoglycan. Activation of the innate immune system contributes to the development and progression of insulin resistance. The present study aimed to determine the presence of NOD1 and NOD2 in human adipose cells as well as to assess their functionality.

METHODS

Subcutaneous abdominal fat from obese subjects was biopsied and characterized for NOD expression using quantitative real-time PCR (qPCR). Human adipocytes were stimulated with iE-DAP (NOD1-specific ligand), and NOD1, proinflammatory cytokine production and nuclear factor (NF)-κB activation were quantified using qPCR, enzyme-linked immunosorbent assay (Elisa) and luciferase assay. Insulin-stimulated glucose uptake was determined by measuring 2-deoxy-D-[(3)H] glucose uptake. Expression and phosphorylation of IRS-1, Akt and JNK were evaluated using Western blotting.

RESULTS

NOD1/NOD2 mRNA expression was induced during adipocyte differentiation and enhanced in human adipose depots. Stimulation of isolated human adipocytes with iE-DAP induced NF-κB p65 nuclear translocation and a marked increase in proinflammatory cytokine production, including MCP-1, IL-6 and IL-8. NOD1 activation weakened insulin signal transduction as revealed by increased JNK and IRS-1 Ser307 phosphorylation, inhibited IRS-1 tyrosine phosphorylation, and reduced insulin-induced phosphorylation of Akt on Ser473 and Thr308 in human adipocytes. Moreover, NOD1 activation reduced insulin-induced glucose uptake, leading to insulin resistance.

CONCLUSION

These results suggest that NOD1 signaling could be one of the links between innate immunity and insulin resistance in human adipocytes. This study provides supporting evidence for NOD1 protein as a component of innate immunity involved in insulin resistance.

A Mediterranean dietary intervention in persons at high risk of colon cancer: recruitment and retention to an intensive study requiring biopsies

This study recruited persons at increased risk of colon cancer to an intensive dietary intervention study that required biopsies of the colon by flexible sigmoidoscopy at baseline and after six months of intervention. A total of 1314 individuals contacted the study, and only 16 individuals indicated that the sigmoidoscopy procedure was an obstacle to study participation. A total of 270 individuals completed a screening visit and signed a screening consent form. Inquiries about the study tended to be fewer in the winter and late summer. Failure to return food records was the most common reason for exclusion. Dietary recall at enrollment indicated that subjects were consuming significantly more vegetables, lower sodium and a lower glycemic load on the day before starting the study vs. during the eligibility phase which might have an impact on biomarker measures. This makes it important to capture dietary changes in the period between determination of eligibility and enrollment. Subjects (n=120) were randomized to follow a Healthy Eating or a Mediterranean Diet, each of which required substantial dietary record-keeping. The study completion rate was 78%, and subjects reported high satisfaction with study participation. Of the 93 individuals who completed the study, only one refused the flexible sigmoidoscopy at the final visit. These findings suggest that flexible sigmoidoscopy does not appear to be a barrier for recruitment of high-risk individuals to an intensive dietary intervention trial, but that completing food records can be.

Cardiovascular risk and dietary sugar intake: is the link so sweet?

Soft drinks and sugar-sweetened beverages have been targeted as one of the primary culprits in the escalating rates of obesity and diabetes and reduction of added sugars is considered between the goals to achieve in order to promote cardiovascular health and to reduce deaths from cardiovascular causes. Many reliable mechanisms, such as dislypidemia, inflammation and enhanced oxidative stress, have been proposed to support a causal link between sugar sweetened beverages intake and cardiovascular risk, but the ultimate underlying pathways remain to be determined in adequately designed studies. Furthermore, while epidemiological evidence strongly supports an association between sugar sweetened beverages consumption and obesity, type 2 diabetes mellitus or cardiovascular risk, incongruous findings yielded by clinical trials, or formal meta-analyses make difficult to draw firm conclusions in this regard. Further and rigorous studies are needed to better understand the role of sugar sweetened beverages in the etiology of cardiovascular diseases and to better address the warnings and decisions of regulatory authorities on public health worldwide.

Assessment of selected nutrient intake and adipocytokine profile among Saudi children and adults

We report the dietary intake of selected nutrients in apparently healthy adults and children and its correlation with circulating levels of serum leptin and resistin. In this observational study, 47 Saudi children (mean age 13.1 ± 2.8 year) and 47 adults (mean age 45.7 ± 10.5 year) were recruited. Anthropometric data and lipid profile were obtained. Food intake was assessed by a food questionnaire and a 24-hour diet recall method. The dietary intake of selected nutrients was compared with the estimated average requirement (EAR) or adequate intake (AI) for establishing nutritional status. Results demonstrated that the levels of choline and calcium intake were significantly lower than the EAR in adults (p= 0.01 and 0.04, respectively) and relatively low in children. The level of manganese in adults was significantly higher (p= 0.02) than their AI level. The increasing levels of dietary vitamin B6 and B12 were associated with a significant increase in serum concentrations of leptin in adults and children (p=0.02). Overall, the dietary intakes of selected nutrients in Saudi adults and children were not adequate with most of them below cut-off EAR values except for essential amino acids.

Management of the metabolic/bariatric surgery patient

There is currently a global pandemic of obesity and obesity-engendered comorbidities; in particular, certain major chronic metabolic diseases (eg, type 2 diabetes) which markedly reduce life expectancy and quality of life. This review is predicated on the fact that management of the obese patient is a primary concern of all physicians and health care providers, and that metabolic/bariatric surgery is a highly successful therapeutic option for this disease.

Contribution of visceral fat accumulation to carotid intima-media thickness in a Chinese population

Objective:

Recent observational studies have reported that body fat distribution might be differentially associated with subclinical atherosclerosis. We previously reported that visceral fat area (VFA) ⩾80 cm² is the optimal cutoff for identifying abdominal obesity in Chinese subjects. We examined whether VFA ⩾80 cm² reflects the association between abdominal obesity and subclinical atherosclerosis, and if determination of the visceral fat quantity is useful for assessing subclinical atherosclerosis in asymptomatic individuals.

Methods and results:

Participants (N=1005, men 515, women 490, 34–66 years) free of cardiovascular disease underwent magnetic resonance imaging and carotid ultrasound assessment to quantify VFA and carotid intima–media thickness (C-IMT). Overweight/obese subjects (body mass index (BMI) ⩾25.0 kg m⁻²) had a higher C-IMT than lean subjects (BMI <25.0 kg m⁻²) (P<0.01). Subjects with VFA ⩾80 cm² had significantly higher C-IMT than those without abdominal obesity regardless of BMI (P<0.01). By multivariate regression analysis adjusted for anthropometric measurements and cardiovascular risk factors, waist circumference but not BMI was independently correlated with C-IMT in men (P<0.001). Similar findings were observed with an accurate obesity indices adjusted model, which showed that VFA was an independent risk factor for increased C-IMT in men but not in women.

Conclusions:

VFA ⩾80 cm² effectively identified carotid atherosclerosis for both lean and obese individuals in middle-aged Chinese men.

Migraine and obesity: epidemiology, possible mechanisms and the potential role of weight loss treatment

Migraine and obesity are two public health problems of enormous scope that are responsible for significant quality of life impairment and financial cost. Recent research suggests that these disorders may be directly related with obesity exacerbating migraine in the form of greater headache frequency and severity, or possibly increasing the risk for having migraine. The relationship between migraine and obesity may be explained through a variety of physiological, psychological and behavioural mechanisms, many of which are affected by weight loss. Given that weight loss might be a viable approach for alleviating migraine in obese individuals, randomized controlled trials are needed to test the effect of weight loss interventions in obese migraineurs. Large-scale weight loss trials have shown that behavioural interventions, in particular, can produce sustained weight losses and related cardiovascular improvements in patients who are diverse in body weight, age and ethnicity. Consequently, these interventions may provide a useful treatment model for showing whether weight loss reduces headache frequency and severity in obese migraineurs, and offering further insight into pathways through which weight loss might exert an effect.

Differences in the laboratory parameters of obese and healthy Hungarian children and their use in automatic classification

Obesity is a rapidly spreading endemic in almost every country of the developed world, of which Hungary is no exception. By a joint research project we aim to deepen our understanding of obesity-associated, and especially obesity-predicting changes of clinical markers (anthropometric indices, body composition, laboratory results etc.) in children, especially in teenage population. This paper presents the preliminary results of our investigations which pertain to obesity-related alterations in routine blood test parameters. For that end, we examined 340 healthy and obese children. Results show that there are differences between the routine laboratory parameters of obese and healthy subjects that are both statistically significant and medically interesting. We point out these differences in a statistically precise way, and show a method which can be efficiently used to classify children based on their laboratory parameters. This result can be used later to develop a more realistic model to predict the risk of obesity.

Association between anthropometric measures of obesity, metabolic disturbances and polymorphism G-308A of the tumor necrosis factor-alpha gene in children

Introduction

TNF-α is one of the most important factors in the development and course of inflammation. It is suggested that polymorphism located in the 5'regulatory region of the TNF-α gene at position 308 (guanine [G]→ adenine[A]) may increase the expression of this cytokine in fat tissue and influence the fat mass and insulin resistance.

Objective

To investigate whether the G-308A polymorphism of the TNF-α gene may influence obesity, insulin resistance, fasting plasma lipids, serum leptin levels, and the incidence of metabolic syndrome.

Materials and methods

The obese group included 124 children with simple obesity (72 girls and 52 boys) aged 10-18 (mean age 15 years) with SDS of BMI ≥ 2.0. A control group consisted of 56 healthy non-obese children (36 girls and 20 boys) aged 11-18 (mean age 14 years) with SDS of BMI < 1.0. Polymorphism identification was performed in total genomic DNA, using PCR-RFLP method.

Results

Carriers of A (AG+AA) allele among the obese children were significantly more frequent than in the control group (OR = 2.29, 95% CI 1.2-4.4, χ²= 6.24, P < 0.05). Carriers of A alleles showed a higher concentrations of fasting glucose (81.3 ± 10.5 vs. 77.4 ± 10.3 mg/dl; P < 0.05), but lower values of fasting insulin (15.1 ± 7.3 vs. 19.0 ± 9.5 μIU/ml; P < 0.05), lower values of HOMA index (3.0 ± 1.5 vs. 3.7 ± 2.0; P < 0.05). In the group of boys, carriers of A alleles showed a tendency for lower concentrations of HDL (43.8 ± 12.6 vs. 48.3 ± 11.8 mg/dl; P < 0.05). Blood pressure and leptin level did not differ between the obese children with gene polymorphism and those of wild homozygous. The incidence of the full metabolic syndrome (MetS) in the children, according to the IDF definition, was 33%. The presence of the MetS in children with wild homozygous GG and carriers of A allele of TNF-α polymorphism gene did not show statistical differences (OR = 1.38; 95% CI 0.6-3.1, χ²= 0.58).

Conclusions

1/Polymorphism G-308A of the TNF-α gene is more common in children with obesity; and 2/Polymorphism G-308A of the TNF-α gene does not seem to be associated with the grade of obesity, insulin resistance, lipid profile, leptin levels, and the incidence of metabolic syndrome in obese children.

HIV and general cardiovascular risk

The incidence of cardiovascular disease (CVD) is increasing in HIV-infected people. Risk factors such as hyperlipidemia, impaired glucose tolerance, and insulin resistance have become common. CVD in HIV may also be related to nontraditional risk factors including accumulation of visceral fat, inflammation secondary to HIV, and effects of some antiretroviral drugs. This cross-sectional study described the CVD risk factors of 123 adults living with HIV and calculated the 10-year estimate for general cardiovascular risk score. Results showed that approximately 25% of the participants were considered to be at high risk for developing CVD in the next 10 years. Increased waist circumference and longer duration of smoking habit were associated with elevated general cardiovascular risk scores. Similar to the general population, most of the identified risks could be modified through lifestyle management.

Effects of a Therapeutic Lifestyle Modification Program on Inflammatory Chemokines and Insulin Resistance in Subjects With Metabolic Syndrome

Background. Although therapeutic lifestyle modification (TLM) effectively improves the values of diagnostic biomarkers of metabolic syndrome, less is known about its effects on inflammatory chemokines and insulin resistance (IR) in patients with this syndrome. Objectives. To examine the effects of a short-term TLM program on inflammatory chemokines (monocyte chemoattractant protein-1 [MCP-1], retinol binding protein-4 [RBP-4]) and IR in subjects with metabolic syndrome. Method. Twenty-nine women (aged 66.5 ± 9.5 years) with metabolic syndrome were randomly assigned to the TLM intervention group (n = 16) or control group (n = 13). The TLM intervention group was provided with 4 weeks of health screening, education, exercise, diet, and counseling. Participants in the control group were instructed to maintain their usual lifestyle behavior. Outcome variables measured included MCP-1, RBP-4, fasting glucose, fasting insulin, and homeostasis model assessment (HOMA). An intention-to-treat strategy was not followed, and the final number of subjects in the analysis was 22 (14 in the TLM group and 8 in the control group). Results. After a 4-week TLM program, MCP-1, fasting insulin, and HOMA were significantly decreased in the TLM group compared to those in the control group (all p < .05). Conclusions. We conclude that a short-term TLM program could be effective for improving inflammatory state and IR, which are significant preceding biomarkers for cardiovascular complications in subjects with metabolic syndrome.

Relationships among obesity, inflammation, and insulin resistance in African Americans and West Africans

Several research studies in different populations indicate that inflammation may be the link between obesity and insulin resistance (IR). However, this relationship has not been adequately explored among African Americans, an ethnic group with disproportionately high rates of obesity and IR. In this study, we conducted a comparative study of the relationship among adiposity, inflammation, and IR in African Americans and West Africans, the ancestral source population for African Americans. The associations between obesity markers (BMI and waist-to-hip ratio (WHR)), inflammatory markers (high-sensitivity C-reactive protein (hsCRP), haptoglobin, interleukin (IL)-6, and tumor necrosis factor (TNF)-alpha), and IR (homeostasis model assessment of insulin resistance (HOMA(IR))) were evaluated in 247 West Africans and 315 African Americans. In average, African Americans were heavier than the West Africans (by an average of 1.6 BMI units for women and 3 BMI units for men). Plasma hsCRP, haptoglobin, and IL-6 (but not TNF-alpha level) were higher in African Americans than in West Africans. In both populations, BMI was associated with markers of inflammation and with HOMA(IR), and these associations remained significant after adjusting for sex and age. However, the pattern of associations between measured inflammatory markers and IR was different between the two groups. In West Africans, hsCRP was the only inflammatory marker associated with IR. In contrast, hsCRP, haptoglobin, and IL-6 were all associated with IR in African Americans. Interestingly, none of the associations between markers of inflammation and IR remained significant after adjusting for BMI. This finding suggests that in African Americans, the relationship between inflammatory markers and IR is mediated by adiposity.

The aporphine alkaloid boldine induces adiponectin expression and regulation in 3T3-L1 cells

Adiponectin is an adipokine secreted by differentiated adipocytes. Clinical studies suggest a negative correlation between oxidative stress and adiponectin levels in patients with metabolic syndrome or cardiovascular disease. Natural compounds that can prevent oxidative stress mediated inhibition of adiponectin may be potentially therapeutic. Boldine, an aporphine alkaloid abundant in the medicinal plant Peumus boldus, is a powerful antioxidant. The current study demonstrates the effects of boldine on the expression of adiponectin and its regulators, CCAAT/enhancer binding protein-alpha (C/EBPalpha) and peroxisome proliferator-activated receptor (PPAR)-gamma, in 3T3-L1 cells. Differentiated 3T3-L1 adipocytes were exposed to either hydrogen peroxide (H(2)O(2)) (100 microM) or tumor necrosis factor-alpha (TNFalpha) (1 ng/mL) for 24 hours in the presence or absence of increasing concentrations of boldine (5-100 microM). Quantitative polymerase chain reaction showed that both the oxidants decreased the mRNA levels of adiponectin, PPARgamma, and C/EBPalpha to half of the control levels. Boldine, at all concentrations, counteracted the inhibitory effect of H(2)O(2) or TNFalpha and increased the expression of adiponectin and its regulators. The effect of boldine on adiponectin expression was biphasic, with the lower concentrations (5-25 microM) having a larger inductive effect compared to higher concentrations (50-100 microM). Boldine treatment alone in the absence of H(2)O(2) or TNFalpha was also able to induce adiponectin at the inductive phase of adipogenesis. Peroxisome proliferator response element-luciferase promoter transactivity analysis showed that boldine interacts with the PPAR response element and could potentially modulate PPAR responsive genes. Our results indicate that boldine is able to modulate the expression of adiponectin and its regulators in 3T3-L1 cells and has the potential to be beneficial in obesity-related cardiovascular disease.

Influence of birth weight on gene regulators of lipid metabolism and utilization in subcutaneous adipose tissue and skeletal muscle of neonatal pigs

Epidemiological studies suggest that low-birth weight infants show poor neonatal growth and increased susceptibility to metabolic syndrome, in particular, obesity and diabetes. Adipose tissue development is regulated by many genes, including members of the peroxisome proliferator-activated receptor (PPAR) and the fatty acid-binding protein (FABP) families. The aim of this study was to determine the influence of birth weight on key adipose and skeletal muscle tissue regulating genes. Piglets from 11 litters were ranked according to birth weight and 3 from each litter assigned to small, normal, or large-birth weight groups. Tissue samples were collected on day 7 or 14. Plasma metabolite concentrations and the expression ofPPARG2,PPARA,FABP3, andFABP4genes were determined in subcutaneous adipose tissue and skeletal muscle. Adipocyte number and area were determined histologically. Expression ofFABP3and4was significantly reduced in small and large, compared with normal, piglets in adipose tissue on day 7 and in skeletal muscle on day 14. On day 7,PPARAandPPARG2were significantly reduced in adipose tissue from small and large piglets. Adipose tissue from small piglets contained more adipocytes than normal or large piglets. Birth weight had no effect on adipose tissue and skeletal muscle lipid content. Low-birth weight is associated with tissue-specific and time-dependent effects on lipid-regulating genes as well as morphological changes in adipose tissue. It remains to be seen whether these developmental changes alter an individual's susceptibility to metabolic syndrome.

Obesity is associated with atypia in breast ductal lavage of women with proliferative breast disease

BACKGROUND

Benign proliferative breast disease without atypia slightly increases breast cancer risk but there are currently few clinical options for breast cancer prevention in this group of women.

METHODS

We conducted a pilot study of women with a past diagnosis of proliferative breast disease with a goal to determine if the characteristics of cells obtained by breast ductal lavage were related to nutritional factors.

RESULTS

There were 57 women who enrolled. A total of 39 women yielded nipple aspirate fluid (NAF) samples and 36 underwent breast ductal lavage. Five of the lavage samples were acellular and 28 had at least 200 cells. Surprisingly, atypia was present in 11 women. Presence of atypia was associated with slight changes in morphometric features of the epithelial cells such as measures of circularity as obtained by image analysis, but the only variable significantly different in women with atypia (versus no atypia) was a higher mean body mass index. Body mass index was also significantly correlated with C-reactive protein (CRP) levels in the nipple aspirate fluid, indicating that obesity might have a pro-inflammatory effect on the breast that can contribute to increased rates of atypia.

CONCLUSIONS

Although the clinical significance of atypia in breast ductal lavage is uncertain, these results support further work on prevention of obesity as a strategy for reducing breast cancer risk.

Association between adipocyte fatty acid-binding protein levels and childhood obesity in Korean children

Adipocyte fatty acid-binding protein (A-FABP) is a newly recognized adipokine that plays a role in the development of obesity and insulin resistance in adults. We investigated the association between A-FABP levels and obesity and insulin resistance in school-aged children. One hundred sixty-one 9-year-old Korean children (80 boys and 81 girls) voluntarily participated in this study at school-based health examinations. Weight, height, waist circumference, and blood pressure were measured. Fasting plasma glucose, triglycerides, high-density lipoprotein cholesterol, insulin, and A-FABP levels were measured; and insulin resistance was estimated by the homeostasis model assessment. Subjects with higher body mass index (BMI) percentiles had correspondingly higher concentrations of A-FABP in both boys and girls. Subjects within the highest quartile of A-FABP levels had correspondingly poor metabolic risk profiles (BMI, waist circumference, triglycerides, high-density lipoprotein cholesterol, fasting insulin, and homeostasis model assessment of insulin resistance) compared with those in the lowest A-FABP quartile (P < .01). Serum A-FABP concentrations were significantly correlated with BMI (r = 0.58, P < .01) and waist circumference (r = 0.51, P < .01). However, the significant correlation between serum A-FABP and insulin resistance faded after adjustment for BMI. Adipocyte fatty acid-binding protein was closely associated with obesity or abdominal obesity in children; however, the independent relationship between A-FABP and insulin resistance in children is still unclear and remains to be determined.

Adipocyte fatty acid-binding protein as a determinant of insulin sensitivity in morbid-obese women

The aim of the study was to evaluate human plasma circulating levels of adipocyte fatty acid-binding protein (A-FABP) and its relationship with proinflammatory adipocytokines and insulin resistance in a severely obese cohort, before and 1 year after a surgical gastric bypass. Plasmatic levels of A-FABP were measured in 77 morbid-obese women before and 1 year after bariatric surgery. Anthropometrical parameters and body composition by bioelectrical impedance analysis were determined. Circulating levels of soluble tumor necrosis factor receptor 2 (sTNFR2), Interleukin 18 (IL-18), adiponectin, and high-sensitive C-reactive protein (hsCRP) were also analyzed. Insulin resistance by homeostasis model assessment of insulin resistance (HOMA-IR) index was calculated. After massive weight loss, A-FABP plasmatic levels decreased significantly [7.6 (8.9) vs. 4.3 (5.1); P<0,001] but no association with circulating adipokines or proinflammatory cytokines, both at the beginning and at the end of follow-up, was observed. A decrease in sTNFR2, IL-18, hsCRP, and an increase in adiponectin levels (P<0.001 in all cases) were observed after the gastric bypass. HOMA-IR index improved 1 year after surgery and after multiple regression analysis remained associated with A-FABP after controlling for confounding variables (beta=0.322, P=0.014; R2 for the model 0.281). In morbid-obese women, plasma A-FABP concentrations were dramatically reduced after gastric bypass surgery. After weight loss this protein contributed to HOMA-IR index independently of proinflammatory/antinflammatory cytokine profile. Further studies are warranted to elucidate the role of A-FABP in the pathogenesis of insulin resistance in morbid obesity.

Anti-inflammatory effect of palmitoylethanolamide on human adipocytes

Obesity leads to the appearance of an inflammatory process, which can be initiated even with a moderate weight gain. Palmitoylethanolamide (PEA) is an endogenous lipid, secreted by human adipocytes, that possesses numerous anti-inflammatory properties. The main purpose of this study was to investigate the anti-inflammatory effect of PEA on human adipocytes, as well as in a murine model. The production of tumor necrosis factor-alpha (TNF-alpha) by lipopolysaccharide (LPS)-treated human subcutaneous adipocytes in primary culture and CF-1 mice was investigated by enzyme-linked immunosorbent assay. The effects of PEA on adipocyte TNF-alpha secretion were explored as well as some suspected PEA anti-inflammatory pathways: nuclear factor-kappaB (NF-kappaB) pathway, peroxisome proliferator-activated receptor-alpha (PPAR-alpha) gene expression, and TNF-alpha-converting enzyme (TACE) activity. The effects of PEA on the TNF-alpha serum concentration in intraperitoneally LPS-treated mice were also studied. We demonstrate that the LPS induced secretion of TNF-alpha by human adipocytes is inhibited by PEA. This action is neither linked to a reduction in TNF-alpha gene transcription nor to the inhibition of TACE activity. Moreover, PPAR-alpha is not implicated in this anti-inflammatory activity. Lastly, PEA exhibits a wide-reaching anti-inflammatory action as the molecule is able to completely inhibit the strong increase in TNF-alpha levels in the serum of mice treated with high doses of LPS. In view of its virtual lack of toxicity, PEA might become a potentially interesting candidate molecule in the prevention of obesity-associated insulin resistance.