Probiotic Lactobacillus Species Strengthen Intestinal Barrier Function and Tight Junction Integrity in Experimental Necrotizing Enterocolitis

Abstract

Necrotizing enterocolitis (NEC) is a serious intestinal disease that occurs in newborn infants. It is associated with major morbidity and affects 5% of all infants admitted to neonatal intensive care units. Probiotics have variable efficacy in preventing necrotizing enterocolitis. Tight junctions (TJ) are protein complexes that maintain epithelial barrier integrity. We hypothesized that the probiotics Lactobacillus rhamnosus and Lactobacillus plantarum strengthen intestinal barrier function, promote TJ integrity, and protect against experimental NEC. Both an in vitro and an in vivo experimental model of NEC were studied. Cultured human intestinal Caco-2 cells were pretreated with L. rhamnosus and L. plantarum probiotics. TJ were then disrupted by EGTA calcium switch or LPS to mimic NEC in vitro. Trans-epithelial resistance (TER) and flux of fluorescein isothiocynate dextran was measured. TJ structure was evaluated by ZO-1 immunofluorescence. In vivo effects of ingested probiotics on intestinal injury and ZO-1 expression were assessed in a rat model of NEC infected with Cronobacter sakazakii (CS). Caco-2 cells treated with individual probiotics demonstrated higher TER and lower permeability compared to untreated cells (p<0.0001). ZO-1 immunofluorescence confirmed TJ stability in treated cells. Rat pups fed probiotics alone had more intestinal injury compared with controls (p=0.0106). Probiotics were protective against injury when given in combination with CS, with no difference in intestinal injury compared to controls (p=0.21). Increased permeability was observed in the probiotic and CS groups (p=0.03, p=0.05), but not in the probiotic plus CS group (p=0.79). Lactobacillus sp. strengthened intestinal barrier function and preserved TJ integrity in an in vitro experimental model of NEC. In vivo, probiotic bacteria were not beneficial when given alone, but were protective in the presence of CS in a rat model of NEC.

Probiotic Lactobacillus plantarum Promotes Intestinal Barrier Function by Strengthening the Epithelium and Modulating Gut Microbiota

“…Alternatively, the observed increase in Lactobacillus abundance may have resulted from the proliferation of the administered probiotic strain ( Takahashi et al, 2007 ). Certain lactobacilli, such as L. rhamnosus , L. reuteri , and L. plantarum , protect TJ proteins after stress and infection and may, therefore, contribute to TJ integrity and intestinal barrier function ( Yang et al, 2015 ; Blackwood et al, 2017 ). Further studies are needed to investigate specific species and their effects on piglet epithelial TJ proteins.…”

The Effect of the Ultra-High-Pressure Homogenization of Protein Encapsulants on the Survivability of Probiotic Cultures after Spray Drying

“…Powdered SPI (ProFam 646, Archer Daniels Midland Company, Chicago, IL, USA) and Powdered WPI (ISOPURE, The Isopure company, Downers Grove, IL, USA) were dissolved in reverse osmosis water to yield 9% suspensions that were stored at 4 • C for 24 h prior to any UHPH or culture suspension in order to ensure full hydration of the powders and provide a sufficiently low inlet temperature during processing. A pure culture sample of Lactobacillus plantarum, (NRRL B-1927 aka ATCC 10241) originally isolated from sauerkraut and frequently identified as a probiotic [19][20][21], was obtained from the USDA-ARS Culture collection (Peoria, IL, USA) and used to propagate all cultures used in this study.…”

Bacillus amyloliquefaciens Ameliorates H2O2-Induced Oxidative Damage by Regulating Transporters, Tight Junctions, and Apoptosis Gene Expression in Cell Line IPEC-1

“…Probiotics are live microorganisms that, when ingested in adequate amounts, provide health benefits to the host. More recently, studies have shown that some beneficial effects of probiotic application include regulation of gut microbiota [8], enhancement of the mucosal barrier [9], stimulation of the immune system [10], and protection of epithelia [11]. Our team has previously shown that Bacillus amyloliquefaciens SC06 (Ba) is beneficial to intestinal tract of piglets, which also has a great antioxidant effect on IPEC-1 cells by regulating the Nrf2/Keap1 pathway [12,13], but effects of oxidative stress on intestinal structure and absorptive function were not completely understood.…”