Portulaca oleracea extracts and their active compounds ameliorate inflammatory bowel diseases in vitro and in vivo by modulating TNF-α, IL-6 and IL-1β signalling

Fermented Portulaca oleracea L. Juice: A Novel Functional Beverage with Potential Ameliorating Effects on the Intestinal Inflammation and Epithelial Injury

P. oleracea L. contains high level of nutrients and biologically active compounds. Recently, lactic fermentation has been proposed as a biotechnological option to enrich the profile of biogenic compounds of Portulaca oleracea L. puree. This study investigated the capability of fermentation by selected lactic acid bacteria to enhance the restoring features of Portulaca oleracea juice towards intestinal inflammation and epithelial injury. Lactic acid fermentation markedly increased the total antioxidant capacity of P. oleracea juice, preserved the inherent levels of vitamins C, A, and E, and increased the bioavailability of the level of vitamin B₂ and that of phenolics. The effects of fermented P. oleracea juice on a Caco-2 cell line were investigated using an in vitro model closest to the in vivo conditions. Fermented P. oleracea juice strongly decreased the levels of pro-inflammatory mediators and reactive oxygen species. It also counteracted the disruption of the Caco-2 cell monolayers treated with the inflammatory stimulus. We used a diversified spectrum of lactic acid bacteria species, and some effects appeared to be strains- or species-specific. Fermentation with Lactobacillus kunkeei B7 ensured the best combination for the content of bioactive compounds and the ability to counteract the intestinal inflammation and epithelial injury.

The protective and anti-inflammatory effects of a modified glucagon-like peptide-2 dimer in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic, recurrent, and remitting inflammatory disease resulting from immune dysregulation in the gut. As a clinically frequent disease, it can affect individuals throughout their lives, with multiple complications. Glucagon-like peptide 2 (GLP-2) is a potent epithelium-specific intestinal growth factor. However, native GLP-2 has a relatively short half-life in human circulation because of extensive renal clearance and rapid degradation by the proteolytic enzyme dipeptidyl peptidase-IV (DPP-IV). Previously, We prepared a recombinant GLP-2 variant (GLP-2②), which has increased half-life and activity as compared to the [Gly²]GLP-2 monomer. The aim of the present study was to investigate the protective potential of GLP-2② in IBD models. LPS-induced in vitro model and dextran sulfate sodium (DSS)-induced in vivo model were used to study the anti-inflammatory and therapeutic effect of GLP-2②. We found that treated with GLP-2② showed a significantly reduction in the secretion of inflammatory cytokines. Furthermore, GLP-2② alleviated symptoms of DSS-induced colitis. GLP-2② treated mice displayed an increase in body weight, lower colitis scores, and fewer mucosal damage compared with GLP-2 treated mice. MPO activities, protein expression of NLRP3 and COX2 in the colon tissues were significantly reduced in GLP-2② groups. Importantly, the ameliorative effect of GLP-2② was related to anti-apoptosis effect in colon tissues. These findings demonstrated that GLP-2② may offer a superior therapeutic benefit over [Gly²]GLP-2 monomer for treatment of IBD.