The stimulation with LPS increased the production of IL-6 and IL-1β while PM decreased the production of IL-6 in WT macrophages. In KO macrophages, LPS increased the production of TNF-α and IL-6 and PM decreased the production of TNFα.The expression of inflammatory markers such NFκB and IL1β were increased by LPS and decreased by PM in both WT and KO macrophages. PM reduced the expression of MyD88 and caspase-1 in KO macrophages, and the expression of TLR4 and HIF-1αin both WT and KO macrophages, although LPS had not effect. CD86, an inflammatory macrophage marker, was reduced by PM independently of genotype. PM increased PPARγ and reduced PPARβ gene expression in macrophages of both genotypes, and increased ACOX-1 expression in KO macrophages. In conclusion, PM promotes anti-inflammatory effects in macrophages exposed to LPS through inhibition of inflammasome pathway, which was independent of PPARα, PPARϒ and AMPK, thus the molecular mechanisms of anti-inflammatory response caused by PM is still unclear.

BackgroundPrevious studies have shown an association between adiposity, especially intra-abdominal adipose tissue, and hemodynamic/metabolic comorbidities in adults, however it is not clear in pediatric population. The aim of the study was to analyze the relationship between non-alcoholic fatty liver disease (NAFLD) and components of metabolic syndrome (MS) with values of intra-abdominal (IAAT) and subcutaneous (SCAT) adipose tissue in obese children and adolescents.MethodsCross-sectional study. Subjects: 182 obese sedentary children and adolescents (aged 6 to 16 y), identified by the body mass index (BMI). Measurements: Body composition and trunk fat by dual-energy X-ray absorptiometry- DXA; lipid profile, blood pressure and pubertal stage were also assessed. NAFLD was classified as absent (0), mild (1), moderate (2) and severe (3), and intra-abdominal and subcutaneous abdominal fat thickness were identified by ultrasound. The MS was identified according to the cut offs proposed by World Health Organization adapted for children and adolescents. The chi-square test was used to compare categorical variables, and the binary logistic regression indicated the magnitude of the associations adjusted by potential cofounders (sex, age, maturation, NAFLD and HOMA-IR).ResultsHigher quartile of SCAT was associated with elevated blood pressure (p = 0.015), but not associated with NAFLD (p = 0.665). Higher IAAT was positively associated with increased dyslipidemia (p = 0.001), MS (p = 0.013) and NAFLD (p = 0.005). Intermediate (p = 0.007) and highest (p = 0.001) quartile of IAAT were also associated with dyslipidemia, independently of age, sex, maturation, NAFLD and HOMA-IR (homeostatic model assessment-insulin resistance).ConclusionObese children and adolescents, with higher IAAT are more prone to develop MS and NAFLD than those with higher values of SCAT, independent of possible confounding variables.

BackgroundNonalcoholic fatty liver disease (NAFLD) is a disorder associated with excessive fat accumulation, mainly in the intra-abdominal region. A simple technique to estimate abdominal fat in this region could be useful to assess the presence of NAFLD, in obese subjects who are more vulnerable to this disease. The aim of this cross-sectional study was to verify the reliability of waist circumference and body composition variables to identify the occurrence of NAFLD in obese children and adolescents.MethodsSample was composed of 145 subjects, aged 11 to 17 years. Assessments of waist circumference (WC), trunk fat mass (TFM) and fat mass (FM) by dual-energy X-ray absorptiometry (DXA) and ultrasound for diagnosis of NAFLD and intra-abdominal adipose tissue (IAAT) were used. Correlation between variables was made by Spearman’s coefficients; ROC curve parameters (sensitivity, specificity, area under curve) were used to assess the reliability of body composition variables to assess the presence of NAFLD. Statistical significance was set at 5%.ResultsSignificant correlations were observed between NAFLD and WC (p = 0.001), TFM (p = 0.002) and IAAT (p = 0.001). The higher values of area under the ROC curve were for WC (AUC = 0.720), TFM (AUC = 0.661) and IAAT (AUC = 0.741).ConclusionsOur findings indicated that TFM, IAAT and WC present high potential to identify NAFLD in obese children and adolescents.

Macrophages are cells of the innate immune response that trigger inflammation resolution. The phenotype of "classically activated macrophages" (M1) has anti-tumoricidal and anti-bactericidal activities. On the other hand, "alternatively activated macrophages" (M2) are involved in tissue remodeling and immunomodulatory functions. The change in the polarization of macrophages varies according to the diversity of cytokines present in the microenvironment or by the stimuli of an antigen. It involves such factors as interferon-regulatory factors, peroxisome proliferator-activated receptors (PPARs), hypoxia-inducible factors (HIFs), and signal transducers and activators of transcription (STATs). Switching the phenotype of macrophages can help attenuate the development of an inflammatory disease. Exercise can promote alterations in the number of innate immune cells and stimulates phagocytic function. Chronic exercise seems to inhibit macrophage infiltration into adipose tissue by attenuating the expression of F4/80 mRNA. Furthermore, exercise may also increase the expression of M2 markers and reduce TNF-α and TLR4 mRNA expression, which activates the inflammatory pathway of NF-κB. Chronic exercise reduces β2-adrenergic receptors in monocytes and macrophages by modulating TLR4 signaling as well as suppressing IL-12 production, a stimulator of interferon Y. In this review, we discuss macrophage polarization in metabolic diseases and how exercise can modulate macrophage plasticity.