Novel probiotic evidence of lactobacilli on immunomodulation and regulation of satiety hormones release in intestinal cells

• Lactobacillus strains survive gut conditions in simulated digestion in vitro model.
• Studied Lactobacillus strains are able to adhere on Caco-2 cell model.
• Strains aren't cytotoxic on Caco-2 cells and modulate secretion of interleukins.
• Studied Lactobacillus strains modulate secretion of CCK and GLP-1 on STC-1 cells.

Lactobacilli strains with probiotic traits were tested for their ability to survive to the digestion process modelled during this study. These strains managed to sustain the harsh conditions of the gastric and duodenal phases and showed good adhesion capacities to human Caco-2 cell line. These probiotic microorganisms have survived during these steps, exposed to low pH, high concentration of bile salts and enzymes occurring in the digestion and virtually reached the duodenal compartment in sufficient amount with limited population loss. These lactobacilli strains appeared to be non-cytotoxic after contact with Caco-2 cells for 24 h. Importantly, some of these strains showed immunomodulatory effect, lowering the pro-inflammatory cytokine IL-8 and promoting secretion of the anti-inflammatory IL-10. Besides, Lactobacillus gasseri CMUL34 and Lactobacillus acidophilus CMUL67 strains were able to modulate secretion and expression of two intestinal hormones: the Glucagon-Like Peptide 1 (GLP-1) and the cholecystokinin (CCK) in STC-1 cells.