Influence of food emulsifiers on cellular function and inflammation, a preliminary study

Emulsifiers are extensively used as food additives and their consumption is increasing in Western countries. However, so far only few studies examined their potential effects on intestinal cellular functions and gut inflammation. The aim of this preliminary analysis was to study the emulsifiers and their concentrations capable of causing cellular damage compared to extra virgin olive oil (EVOO). We tested two commonly used emulsifiers (EMI, EMII) and EVOO on Caco-2 cells, derived from a colon carcinoma and widely used as a model of the intestinal inflammation. The diphenyltetrazolium bromide test MTT and clonogenic assay were used to study the effect of emulsifiers on cell viability. Cell migration was determined by the wound-healing assay. The inflammation was studied by measuring the levels of interleukin 6 (IL-6) and monocyte chemoattractant protein-1/C-C motif chemokine ligand 2 (CCL2), multifunctional cytokines with a major role in the acute-phase response. Furthermore, we analyzed the effect of conditioned media of Caco-2 cells treated with EMs on macrophages activation. In conclusion, our preliminary data provide evidence that EMs increase the proliferation and migration rate of Caco-2 cells. Moreover, Caco-2 cells treated with EMs enhance the IL-6 and CCL2 release and activated macrophages, supporting their role as proinflammatory molecules.

First case report of M1 macrophage polarization in an untreated symptomatic patient with toxoplasmosis

Background

In immunocompetent patients, acute toxoplasmosis is usually asymptomatic. We identified M1 macrophages in a case of symptomatic acute Toxoplasma gondii infection that resolved without treatment. M1 macrophages have been demonstrated in animal models of toxoplasmosis, but not in humans.

Case presentation

A 63-year-old woman presented with laterocervical and axillary bilateral lymphadenopathy. Her anamnesis defined an episode of high fever and prolonged asthenia 4 months previously, which suggested an infectious disease. Following laboratory, radiological, and pathological analyses, she was diagnosed with toxoplasmosis. Immunohistochemical analyses were performed on lymph node sections. More than 50% of the macrophages in the lymph node microgranulomas were M1 macrophages, defined by CD68⁺/p-Stat1⁺ staining, and the presence of T helper 1 lymphocytes indicated an immune response known to induce M1 macrophage polarization. Activated endothelial cells were found only in inflamed areas. No therapy was administered before or after diagnosis, and the lymphadenopathy resolved after a follow-up of 5 months.

Conclusions

This is the first report to demonstrate the presence of M1 macrophages in human toxoplasmosis. Our findings contribute to the understanding of the pathogenesis of toxoplasmosis, and encourage further studies on the role of macrophage polarization in human toxoplasmosis.

IL-7-induced phosphorylation of the adaptor Crk-like and other targets

IL-7 is required for T cell differentiation and mature T cell homeostasis and promotes pro-B cell proliferation and survival. Tyrosine phosphorylation plays a central role in IL-7 signaling. We identified by two-dimensional electrophoresis followed by anti-phosphotyrosine immunoblotting and mass spectrometry sixteen tyrosine phosphorylated proteins from the IL-7-dependent cell line D1. IL-7 stimulation induced the phosphorylation of the proteins STI1, ATIC and hnRNPH, involved in pathways related to survival, proliferation and gene expression, respectively, and increased the phosphorylation of CrkL, a member of a family of adaptors including the highly homologous Crk isoforms CrkII and CrkI, important in multiple signaling pathways. We observed an increased phosphorylation of CrkL in murine pro-B cells and in murine and human T cells. In addition, IL-7 increased the association of CrkL with the transcription factor Stat5, essential for IL-7 pro-survival activity. The selective tyrosine kinase inhibitor Imatinib. counteracted the IL-7 pro-survival effect in D1 cells and decreased CrkL phosphorylation. These data suggested that CrkL could play a pro-survival role in IL-7-mediated signaling. We observed that pro-B cells also expressed, in addition to CrkL, the Crk isoforms CrkII and CrkI and therefore utilized pro-B cells conditionally deficient in all three to evaluate the role of these proteins. The observation that the IL-7 pro-survival effect was reduced in Crk/CrkL conditionally-deficient pro-B cells further pointed to a pro-survival role of these adaptors. To further evaluate the role of these proteins, gene expression studies were performed in Crk/CrkL conditionally-deficient pro-B cells. IL-7 decreased the transcription of the receptor LAIR1, which inhibits B cell proliferation, in a Crk/CrkL-dependent manner, suggesting that the Crk family of proteins may promote pro-B cell proliferation. Our data contribute to the understanding of IL-7 signaling and suggest the involvement of Crk family proteins in pathways promoting survival and proliferation.

ROS1 Gene Fusion in Advanced Lung Cancer in Women: A Systematic Analysis, Review of the Literature, and Diagnostic Algorithm

Purpose

Crizotinib, a mesenchymal-epithelial transition/anaplastic lymphoma kinase/c-ros oncogene 1 (ROS1) inhibitor, has recently been approved by the US Food and Drug Administration for the treatment of patients with advanced ROS1-positive non–small-cell lung cancer (NSCLC). Therefore, interest in ROS1 testing is growing. ROS1 gene fusions affect approximately 0.5% to 2% of unselected NSCLCs. Limited data are available on the prevalence and distribution of ROS1 fusions in patients with advanced-stage NSCLC.

Material and Methods

A series of 727 lung adenocarcinomas from patients with stage IV disease, negative for epidermal growth factor receptor and anaplastic lymphoma kinase alterations, were tested for ROS1 fusions by fluorescent in situ hybridization analysis, with confirmation by immunohistochemistry. Results were correlated with clinicopathologic parameters and compared with data from the literature.

Results

ROS1 fusions were detected in 29 patients (4%), including 27 of 266 females (10.2%) and two of 461 males (0.4%; P = 1.2E-10). The mean age of patients with ROS1-positive disease was lower than that of patients with ROS1-negative disease (49.21 v 62.96 years, respectively; P = 1.1E-10). Eleven of 583 smokers (1.9%) and 18 of 144 nonsmokers (12.5%) showed ROS1 rearrangement ( P = 4.05E-7). By logistic regression analysis, ROS1 fusions were independently associated with female sex, younger age at diagnosis, and absence of smoking history, (odds ratios, 12.4, 7.9, and 3.6, respectively). These data, integrated with those reported in the literature, indicate that the prevalence of ROS1 fusions in females and in nonsmokers was higher in patients with advanced disease than in patients with operable disease (11.2% v 3.1%, P < .001; 11.6% v 2.8%, P < .001, respectively). The mean age at diagnosis was significantly lower in patients with advanced disease (49.8 years) than in patients with operable disease (55.6 years; P < .001).

Conclusion

Our data indicate that ROS1 fusions in patients with advanced-stage lung adenocarcinoma are more frequent in females, particularly if young and nonsmokers. A diagnostic algorithm for an accurate screening of ROS1 alterations was elaborated.

A systems biology approach to the hepatic role of the oxysterol receptor LXR in the regulation of lipogenesis highlights a cross-talk with PPARα

The Liver X Receptors (LXRs) α and β and the Peroxisome Proliferator-Activated Receptor α (PPARα) are transcription factors that belong to class II nuclear receptors. They drive the expression of genes involved in hepatic lipid homeostasis and therefore are important targets for the prevention and treatment of nonalcoholic fatty liver disease (NAFLD). LXRs and PPARα are regulated by endogenous ligands, oxysterols and fatty acid derived molecules, respectively. In the liver, pharmacological activation of LXRs leads to the over-expression of genes involved in de novo lipogenesis, while PPARα is critical for fatty acid catabolism in nutrient deprivation. Even if these two nuclear receptors seemed to play opposite parts, recent studies have highlighted that PPARα also influence the expression of genes involved in fatty acids synthesis. In this study, we used pharmacological approaches and genetically engineered mice to investigate the cross-talk between LXRs and PPARα in the regulation of genes responsible for lipogenesis. We first investigated the effect of T0901317 and fenofibrate, two synthetic agonists of LXRs and PPARα, respectively. As expected, T0901317 and fenofibrate induce expression of genes involved LXR-dependent and PPARα-dependent lipogenic responses. Considering such overlapping effect, we then tested whether LXR agonist may influence PPARα driven response and vice versa. We show that the lack of PPARα does not influence the effects of T0901317 on lipogenic genes expression. However, PPARα deficiency prevents the up-regulation of genes involved in ω-hydroxylation that are induced by the LXR agonist. In addition, over-expression of lipogenic genes in response to fenofibrate is decreased in LXR knockout mice as well as the expression of PPARα target genes involved in fatty acid oxidation. Altogether, our work provides in vivo evidence for a central interconnection between nuclear receptors that drive hepatic lipid metabolism in response to oxysterol and fatty acids.