The correlation between fecal microbiota profiles and intracellular junction genes expression in young Iranian patients with celiac disease.

Celiac disease (CD) is characterized by the disruption of the intestinal barrier integrity and alterations in the microbiota composition. This study aimed to evaluate the changes in the fecal microbiota profile and mRNA expressions of intracellular junction-related genes in pediatric patients with CD compared to healthy controls (HCs). Thirty treated CD patients, 10 active CD, and 40 HCs were recruited. Peripheral blood (PB) and fecal samples were collected. Microbiota analysis was performed using quantitative real-time PCR (qPCR) test. The mRNA expressions of ZO-1, occludin, β-catenin, E-cadherin, and COX-2 were also evaluated. In active and treated CD patients, the PB expression levels of ZO-1 ( p  = 0.04 and 0.002, respectively) and β-catenin ( p  = 0.006 and 0.02, respectively) were lower than in HCs. PB Occludin's level was upregulated in both active and treated CD patients compared to HCs ( p  = 0.04 and 0.02, respectively). However, PB E-cadherin and COX-2 expression levels and fecal mRNA expressions of ZO-1, occludin, and COX-2 did not differ significantly between cases and HCs (P˃0.05). Active CD patients had a higher relative abundance of the Firmicutes ( p  = 0.04) and Actinobacteria ( p  = 0.03) phyla compared to treated subjects. The relative abundance of Veillonella ( p  = 0.04) and Staphylococcus ( p  = 0.01) genera was lower in active patients in comparison to HCs. Researchers should explore the precise impact of the gut microbiome on the molecules and mechanisms involved in intestinal damage of CD. Special attention should be given to Bifidobacteria and Enterobacteriaceae, as they have shown a significant correlation with the expression of tight junction-related genes.