How two sites of inflammation promote carcinogenesis: The role of macrophages in inflammation associated carcinogenesis

The roles of tumor-associated macrophages in tumor angiogenesis and metastasis

Tumor associated macrophages (TAMs) are the most frequent immune cells within tumor microenvironment (TME). There is growing evidence that TAMs are involved in tumor progression via multiple mechanisms. TAMs create an immunosuppressive TME by producing growth factors, chemokines, and cytokines which modulate recruitment of immune cells and inhibit anti-tumor responses. They also serve as angiogenesis promoting cells by production of pro-angiogenic factors and matrix metalloproteinases (MMPs) and vascular constructing which guarantee supplying oxygen and nutrients to solid tumor cells. Furthermore, TAMs play important functions in tumor metastasis through contributing to invasion, extravasation, survival, intravasation, and colonization of tumor cells. In this review, we summarized macrophage classification, TAMs polarization, and mechanisms underlying TAM-promoting angiogenesis and metastasis.

Integrated omics profiling of dextran sodium sulfate-induced colitic mice supplemented with Wolfberry (Lycium barbarum)

We used a multi-omics profiling approach to investigate the suppressive effects of 2% Wolfberry (WOL)-enriched diets on dextran sodium sulfate (DSS)-induced colitis in mice. It was observed that in mice fed the WOL diet, the disease activity index, colon shortening, plasma concentrations of matrix metalloproteinase-3 and relative mesenteric fat weight were significantly improved as compared to the DSS group. Results from colon transcriptome and proteome profiles showed that WOL supplementation significantly ameliorated the expression of genes and proteins associated with the integrity of the colonic mucosal wall and colonic inflammation. Based on the hepatic transcriptome, proteome and metabolome data, genes involved in fatty acid metabolism, proteins involved in inflammation and metabolites related to glycolysis were downregulated in WOL mice, leading to lowered inflammation and changes in these molecules may have led to improvement in body weight loss. The integrated nutrigenomic approach thus revealed the molecular mechanisms underlying the ameliorative effect of whole WOL fruit consumption on inflammatory bowel disease.

The anti-inflammatory potential of a moderately hydrolysed casein and its 5 kDa fraction in in vitro and ex vivo models of the gastrointestinal tract

Bioactive peptides from milk can impart a wide range of physiological benefits without the allergies and intolerance associated with the consumption of whole milk. The objective of this study was to characterise the anti-inflammatory properties of intact sodium caseinate (NaCAS), a moderately hydrolysed NaCAS enzyme hydrolysate (EH) and its 5 kDa fraction (5kDaR), in both in vitro and ex vivo systems. In vitro, Caco-2 cells were stimulated with tumor necrosis factor (TNF) α and co-treated ± casein hydrolysates or dexamethasone (control). The inflammatory marker interleukin (IL)-8 was measured by ELISA in the supernatant at 24 h. Ex vivo, porcine colonic tissues were stimulated with lipopolysaccharide (LPS) and co-treated with casein hydrolysates for 3 h from which the relative expression of a panel of cytokines was measured in vitro. While the steroid dexamethasone brought about a 41.6% reduction in the IL-8 concentration in the supernatant, the 5kDaR reduced IL-8 by 59% (P < 0.05) when compared to the TNFα stimulated Caco-2 cells. In the ex vivo system, 5kDaR was associated with decreases in IL-1α, IL-1β, IL-8 and TGF-β expression and an increase in IL-17 expression (P < 0.05) relative to the LPS challenged tissues. We concluded, that a 5 kDa casein fraction demonstrates potent anti-inflammatory effects both in in vitro and ex vivo models of the gastrointestinal tract.

Anti-inflammatory effects of a casein hydrolysate and its peptide-enriched fractions on TNFα-challenged Caco-2 cells and LPS-challenged porcine colonic explants

Bioactive milk peptides are reported to illicit a range of physiological benefits and have been proposed as potential functional food ingredients. The objective of this study was to characterize the anti-inflammatory properties of sodium caseinate (NaCAS), its enzyme hydrolysate (EH) and peptide-enriched fractions (5 kDa retentate [R], 1 kDaR and 1 kDa permeate [P]), both in vitro using a Caco-2 cell line, and also ex vivo using a porcine colonic tissue explant system. Caco-2 cells were stimulated with tumour necrosis factor alpha (TNFα) and co-treated with casein hydrolysates for 24 h. Following this, interleukin (IL)-8 concentrations in the supernatant were measured using enzyme-linked immunosorbent assay. Porcine colonic tissue was stimulated with lipopolysaccharide and co-treated with casein hydrolysates for 3 h. The expression of a panel of inflammatory cytokines was measured using qPCR. While dexamethasone reduced the IL-8 concentration by 41.6%, the 1 kDaR and 1 kDaP fractions reduced IL-8 by 68.7% and 66.1%, respectively, relative to TNFα-stimulated Caco-2 cells (P < 0.05). In the ex vivo system, only the 1 kDaR fraction elicited a decrease inIL1-α,IL1-β,IL-8,TGF-β andIL-10 expression (P < 0.05). This study provides evidence that the bioactive peptides present in the 1 kDaR fraction of the NaCAS hydrolysate possess anti-inflammatory properties in vitro and ex vivo. Further in vivo analysis of the anti-inflammatory properties of the 1 kDaR is proposed.