IL-33/ST2 axis in innate and acquired immunity to tumors

Interleukin-33, a ligand for ST2/T1, has an important role in allergy, autoimmunity and inflammation. The role of IL-33/ST2 axis in cancer is not elucidated. Using metastatic breast cancer model we provide evidence that lack of ST2 signaling led to reduced tumor growth and metastasis and enhanced anti-tumor immunity

Galectin-3 In Obesity And Type 2 Diabetes

Galectin-3 is an important regulator of inflammation and acts as a receptor for advanced-glycation (AGE) and lipoxidation end-products (ALE). Evidence indicates a significant upregulation in circulating levels and visceral adipose tissue production of Galectin-3 in obesity and type 2 diabetes. Recent studies demonstrate development of obesity and dysregulation of glucose metabolism in Galectin-3 “knockout” (KO) mice, which also develop accelerated and more severe pathology in models of atherosclerosis and metabolically-induced kidney damage. Thus, evidence that Galectin-3 is an important player in metabolic disease is accumulating. This review discusses current evidence on the connection between Galectin-3 and metabolic disease, focusing on mechanisms by which this galectin modulates adiposity, glucose metabolism and obesity-associated inflammatory responses

Galectin-3 Deletion Enhances Visceral Adipose Tissue Inflammation and Dysregulates Glucose Metabolism in Mice on a High-Fat Diet

Obesity and type 2 diabetes mellitus (T2DM) constitute major health problems worldwide. Increased visceral adiposity enhances the risk of insulin resistance and type 2 diabetes. The mechanisms involved in obesity-associated chronic inflammation in metabolic tissues (metaflammation) that lead to insulin resistance and dysregulated glucose metabolism are incompletely defined. Galectin-3 (Gal-3), a β-galactoside-binding lectin, modulates immune/inflammatory responses and specifically binds to metabolic danger molecules. To dissect the role of Gal-3 in obesity and diabetes, Gal-3-deficient (LGALS3-/-) and wild-type (WT) C57Bl/6 male mice were placed on a high-fat diet (HFD, 60% kcal fat) or a standard chow diet (10% kcal fat) for 6 months and metabolic, histological and immunophenotypical analyses of the visceral adipose tissue were performed. HFD-fed LGALS3-/- mice had higher body weights and more body weight gain, visceral adipose tissue (VAT), hyperglycaemia, hyperinsulinemia, insulin resistance and hyperlipidemia than diet-matched WT mice. Compared to WT mice, the enlarged VAT in obese LGALS3-/- mice contained larger adipocytes. Additionally, we demonstrate enhanced inflammation in the VAT of LGALS3-/- mice compared with diet-matched WT mice. The VAT of LGALS3-/- mice fed a HFD contained more numerous dendritic cells and proinflammatory F4/80+CD11c+CD11b+ and F4/80high macrophages. In contrast to WT mice, the numbers of CXCR3+ and CD8+ T cells were increased in the VAT of Gal-3-deficient mice after 6 months of high-fat feeding. We provide evidence that Gal-3 ablation results in enhanced HFD-induced adiposity, inflammation in the adipose tissue, insulin resistance and hyperglycaemia. Thus, Gal-3 represents an important regulator of obesity-associated immunometabolic alterations

Innate Lymphoid Cells: Roles In Tumour Genesis And Progression

Innate lymphoid cells (ILCs) represent the most recently identified members of the innate immune system. These cells play important roles in inflammation, tissue remodelling and metabolic disease. ILCs can be subdivided into three major groups according to their cytokine production. The role of ILCs in tumourigenesis and tumour progression is not completely clarified. In this review, we discuss whether and how ILCs are involved in tumour genesis, growth and metastasis

ST2 Deficiency Ameliorates High Fat Diet-Induced Liver Steatosis In BALB/c Mice

Non-alcoholic fatty liver disease (NAFLD) is strongly associated with obesity, but the molecular mechanisms of liver steatosis and its progression to non-alcoholic steatohepatitis and fibrosis are incompletely understood. Immune reactivity plays an important role in the pathogenesis of NAFLD. The IL-33/ST2 axis has a protective role in adiposity and atherosclerosis, but its role in obesity-associated metabolic disorders requires further clarification. To investigate the unresolved role of IL-33/ST2 signalling in NAFLD, we used ST2-deficient (ST2-/-) and wild type (WT) BALB/c mice maintained on a high-fat diet (HFD) for 24 weeks. HFD-fed ST2-/- mice exhibited increased weight gain, visceral adipose tissue weight and triglyceridaemia and decreased liver weight compared with diet-matched WT mice. Compared with WT mice on an HFD, ST2 deletion significantly reduced hepatic steatosis, liver inflammation and fibrosis and downregulated the expression of genes related to lipid metabolism in the liver. The frequency of innate immune cells in the liver, including CD68+ macrophages and CD11c+ dendritic cells, was lower in HFD-fed ST2-/- mice, accompanied by lower TNFα serum levels compared with diet-matched WT mice. Less collagen deposition in the livers of ST2-/- mice on an HFD was associated with lower numbers of profibrotic CD11b+Ly6clow monocytes and CD4+IL-17+ T cells in the liver, lower hepatic gene expression of procollagen, IL-33 and IL-13, and lower serum levels of IL-33 and IL-13 compared with diet-matched WT mice

Primers used for qRT-PCR analysis.

<p>Primers used for qRT-PCR analysis.</p

Liver gene expression in chow and HFD-fed C57Bl/6 and BALB/c mice.

<p>(A) Expression of genes related to lipid metabolism in liver in chow and HFD-fed C57Bl/6 and BALB/c mice. Expression of LXRα and PPARγ was significantly lower in C57Bl/6 mice mice on HFD. (B) Expression of profibrogenic genes in liver in chow and HFD-fed C57Bl/6 and BALB/c mice. Expression of procollagen and TGF-β was significantly higher in C57Bl/6 mice on both diets. The results are shown as the means ± SEM of 9–10 animals per group. *p<0.05. The results are representative of two experiments.</p