(CECT7484 and CECT7485) and (CECT7483) enhance actin cytoskeleton and CYP1A1 expression restoring epithelial permeability alterations induced by irritable bowel syndrome mediators.

Irritable bowel syndrome (IBS) is a multifactorial condition with heterogeneous pathophysiology, including intestinal permeability alterations. The aim of the present study was to assess the ability of a probiotic blend (PB) consisting of two strains (CECT7484 and CECT7485) and one strain of (CECT7483) to recover the permeability increase induced by mediators from IBS mucosal biopsies and to highlight the underlying molecular mechanisms. Twenty-one IBS patients diagnosed according to ROME IV criteria (11 IBS-D and 10 IBS-M) and 7 healthy controls were enrolled. Mucosal mediators spontaneously released by IBS and HC biopsies were collected and incubated with/without the PB (10 and 10 CFU/ml). Paracellular permeability was assessed by evaluating the amount of sulfonic-acid-conjugated to fluorescein passing through the Caco-2 monolayer. RNA was extracted from Caco-2 cells and used to perform qPCR analyses, to evaluate the expression of ZO-1 and β-actin, and RNAseq to evaluate the transcriptomic profile. Untargeted metabolomics was used to characterize metabolites produced by the PB. The PB significantly reduced paracellular permeability after 3 h of incubation. Both doses of the PB significantly recovered the increase in paracellular permeability induced by IBS mediators. qPCR analyses showed that both doses of the PB co-incubated with IBS mediators induced a significant increase in beta-actin expression compared to IBS mediators alone. Concerning IBS subtypes, the high dose of the PB recovered the increase of permeability induced by IBS-D mediators. Transcriptomic analyses, confirmed by qPCR, showed that the high dose of the PB significantly increased CYP1A1 compared to IBS mediators alone. The PB produced a high amount of indole-3-lactic acid. The PB recovers the permeability increase induced by IBS mediators inducing the up-regulation of β-actin. In addition, the PB up-regulates the expression of CYP1A1, known to be involved in the metabolism of xenobiotics, possibly through the production of the indole-3-lactic acid.