Effetti di ceppi selezionati di probiotici su modelli di cellule epiteiali in vitro.

A growing body of evidence support the use of probiotics in the prevention and treatment of difficult healing wounds. Even if several studies in vitro and in vivo have highlighted the pro-healing effects of several probiotic bacteria, the underlying mechanisms are still not fully defined.The doctoral project aimed to investigate the in vitro effects of selected strains of probiotics on two different epithelial models, to study their ability to influence tissue repair. in the first model were analyzed the effect of the soluble fraction of seven selected strains of probiotics on a wound healing model using the HaCaT cell line. Screening of bacterial strains was carried out to identify those able to accelerate the repair process; subsequently the effects of these strains on the two main processes involved in wound healing were evaluated: cell proliferation and migration. The involvement of NO was analyzed in the acceleration process induced by the different bacterial strains evaluating, in particular, the expression of NOS2. In the second model the effects of a probiotic formulation (VIVOMIXX), composed by eight probiotic strains were analyzed on trans-epithelial electrical resistance (TEER), dextran flux, and expression TJ proteins i.e. zonulin-1 (ZO-1) and occludin, in the absence or presence of a heat stress-related damage of cell monolayer. In vitro models, such as those used for this work can be very useful and suitable for an in-vitro verification of the effects of a probiotic or a probiotic combination.