CCL2 level is elevated with metabolic syndrome and CXCL10 level is correlated with visceral fat area in obese children

Extra virgin olive oil extract rich in secoiridoids induces an anti-inflammatory profile in peripheral blood mononuclear cells from obese children

Obesity represents an important public health challenge of the twenty first century reaching epidemic proportions worldwide; this is especially true for the pediatric population. In this context, bioactive compounds from foods are crucial to counteract chronic inflammation as a typical feature of obesity. In particular, extra virgin olive oil (EVOO) is one of the most important functional foods exerting, among others, an anti-inflammatory activity not only due to its major (monounsaturated fatty acids) but also to its minor (phenolics) components, as reported in the last years. However, only a limited number of studies were performed on pediatric population, and even fewer are those focusing on EVOO phenolics that investigate the correlation of the chemical characterization with the biological function. Thus, starting from our in vitro data identifying an EVOO chemical profile characterized by a high content of secoiridoids correlating with an anti-inflammatory effect, we studied the ability of an EVOO extract with the same chemical profile to retain this function ex vivo. Specifically, peripheral blood mononuclear cells (PBMCs) collected from obese children were treated with EVOO and olive oil extracts, characterized by a low polyphenol content, to study the ability of secoiridoids to dampen the inflammatory response. A reduction of pro-inflammatory CD14⁺CD16⁺ monocytes was detected by cytofluorimetric analysis when PBMCs were treated with EVOO as compared to olive oil extracts. According to this, a down modulation of CCL2 and CCL4 chemokines involved in the recruitment of inflammatory cells, was reported in the supernatants of EVOO relative to olive oil extracts treated PBMCs. Moreover, a high-throughput gene expression analysis revealed that PBMCs molecular profile from obese children is greatly modulated after the treatment with EVOO extract in terms of metabolic and inflammatory pathways. Importantly, some of the significantly modulated genes were involved in the pathways promoting the development of severe obesity. Overall, our ex vivo data demonstrated the ability of EVOO to reduce the inflammatory milieu of PBMCs from obese children both at protein and molecular levels. Of note, a good correlation between the EVOO chemical profile and the biological modulations in terms of anti-inflammatory activity was reported.

Beneficial effects of PCSK9 inhibition with alirocumab in familial hypercholesterolemia involve modulation of new immune players

Familial hypercholesterolemia (FH) is associated with low-grade systemic inflammation, a key driver of premature atherosclerosis. We investigated the effects of inhibiting proprotein convertase subtilisin/kexin type 9 (PCSK9) function on inflammatory state, endothelial dysfunction and cardiovascular outcomes in patients with FH. Fourteen patients with FH were evaluated before and 8 weeks after administration of a PCSK9 blocking monoclonal antibody (alirocumab, 150 mg/subcutaneous/14 days). In vivo and ex vivo analysis revealed that alirocumab blunted the attachment of leukocytes to TNFα-stimulated human umbilical arterial endothelial cells (HUAEC) and suppressed the activation of platelets and most leukocyte subsets, which was accompanied by the diminished expression of CX₃CR1, CXCR6 and CCR2 on several leukocyte subpopulations. By contrast, T-regulatory cell activation was enhanced by alirocumab treatment, which also elevated anti-inflammatory IL-10 plasma levels and lowered circulating pro-inflammatory cytokines. Plasma levels of IFNγ positively correlated with levels of total and LDL-cholesterol, whereas circulating IL-10 levels negatively correlated with these key lipid parameters. In vitro analysis revealed that TNFα stimulation of HUAEC increased the expression of PCSK9, whereas endothelial PCSK9 silencing reduced TNFα-induced mononuclear cell adhesion mediated by Nox5 up-regulation and p38-MAPK/NFκB activation, concomitant with reduced SREBP2 expression. PCSK9 silencing also decreased endothelial CX₃CL1 and CXCL16 expression and chemokine generation. In conclusion, PCSK9 inhibition impairs systemic inflammation and endothelial dysfunction by constraining leukocyte-endothelium interactions. PCSK9 blockade may constitute a new therapeutic approach to control the inflammatory state associated with FH, preventing further cardiovascular events in this cardiometabolic disorder.

Systemic Inflammation in Metabolic Syndrome: Increased Platelet and Leukocyte Activation, and Key Role of CX3CL1/CX3CR1 and CCL2/CCR2 Axes in Arterial Platelet-Proinflammatory Monocyte Adhesion

BACKGROUND

Metabolic syndrome is associated with low-grade systemic inflammation, which is a key driver of premature atherosclerosis. We characterized immune cell behavior in metabolic syndrome, its consequences, and the potential involvement of the CX₃CL1/CX₃CR1 and CCL2/CCR2 chemokine axes.

METHODS

Whole blood from 18 patients with metabolic syndrome and 21 age-matched controls was analyzed by flow cytometry to determine the leukocyte immunophenotypes, activation, platelet-leukocyte aggregates, and CX₃CR1 expression. ELISA determined the plasma marker levels. Platelet-leukocyte aggregates adhesion to tumor necrosis factor-α (TNFα)-stimulated arterial endothelium and the role of CX₃CL1/CX₃CR1 and CCL2/CCR2 axes was investigated with the parallel-plate flow chamber.

RESULTS

When compared with the controls, the metabolic syndrome patients presented greater percentages of eosinophils, CD3⁺ T lymphocytes, Mon2/Mon3 monocytes, platelet-eosinophil and -lymphocyte aggregates, activated platelets, neutrophils, eosinophils, monocytes, and CD8⁺ T cells, but lower percentages of Mon1 monocytes. Patients had increased circulating interleukin-8 (IL-8) and TNFα levels and decreased IL-4. CX₃CR1 up-regulation in platelet-Mon1 monocyte aggregates in metabolic syndrome patients led to increased CX₃CR1/CCR2-dependent platelet-Mon1 monocyte adhesion to dysfunctional arterial endothelium.

CONCLUSION

We provide evidence of generalized immune activation in metabolic syndrome. Additionally, CX₃CL1/CX₃CR1 or CCL2/CCR2 axes are potential candidates for therapeutic intervention in cardiovascular disorders in metabolic syndrome patients, as their blockade impairs the augmented arterial platelet-Mon1 monocyte aggregate adhesiveness, which is a key event in atherogenesis.

Adverse Childhood Experiences, Epigenetic Measures, and Obesity in Youth

OBJECTIVE

To determine if measures of adverse childhood experiences and DNA methylation relate to indices of obesity in youth.

STUDY DESIGN

Participants were derived from a cohort of 321 8 to 15-year-old children recruited for an investigation examining risk and resilience and psychiatric outcomes in maltreated children. Assessments of obesity were collected as an add-on for a subset of 234 participants (56% female; 52% maltreated). Illumina arrays were used to examine whole genome epigenetic predictors of obesity in saliva DNA. For analytic purposes, the cohort analyzed in the first batch comprised the discovery sample (n = 160), and the cohort analyzed in the second batch the replication sample (n = 74).

RESULTS

After controlling for race, sex, age, cell heterogeneity, 3 principal components, and whole genome testing, 10 methylation sites were found to interact with adverse childhood experiences to predict cross-sectional measures of body mass index, and an additional 6 sites were found to exert a main effect in predicting body mass index (P < 5.0 × 10^-7, all comparisons). Eight of the methylation sites were in genes previously associated with obesity risk (eg, PCK2, CxCl10, BCAT1, HID1, PRDM16, MADD, PXDN, GALE), with several of the findings from the discovery data set replicated in the second cohort.

CONCLUSIONS

This study lays the groundwork for future longitudinal studies to elucidate these mechanisms further and identify novel interventions to alleviate the health burdens associated with early adversity.

Plasma immunological markers in pregnancy and cord blood: A possible link between macrophage chemo-attractants and risk of childhood type 1 diabetes

PROBLEM

Previous studies have suggested that immune perturbations during pregnancy can affect offspring type 1 diabetes (T1D) risk. We aimed to identify immunological markers that could predict offspring T1D or that were linked to T1D risk factors.

METHOD OF STUDY

We quantified selected circulating immunological markers in mid-pregnancy (interleukin [IL]-1β, IL-1ra, IL-2Rα, IL-2, -4, -5, -6, -10, -12p70, 13, -17A, GM-CSF, IFN-γ, CXCL10, CCL 2, CCL3, CCL4, TNF) and cord blood plasma (neopterin and kynurenine/tryptophan ratio) in a case-control study with 175 mother/child T1D cases (median age 5.8, range 0.7-13.0 years) and 552 controls.

RESULTS

Pre-pregnancy obesity was positively associated with CCL4, CXCL10, kynurenine/tryptophan ratio and neopterin (P < .01). The established T1D SNPs rs1159465 (near IL2RA) and rs75352297 (near CCR2 and CCR3) were positively associated with IL-2Rα and CCL4, respectively (P < .01). There was a borderline association of CCL4 and offspring T1D risk, independent of maternal obesity and genotype. When grouping the immunological markers, there was a borderline association (P = .05) with M1 phenotype and no association between M2-, Th1-, Th2- or Th17 phenotypes and offspring T1D risk.

CONCLUSION

Increased mid-pregnancy CCL4 levels showed borderline associations with increased offspring T1D risk, which may indicate a link between environmental factors in pregnancy and offspring T1D risk.