Background: There is a growing interest in the effects of probiotics for the prevention
and treatment of skin diseases due to their immunomodulatory and antiinflammatory
Objective: To assess a mixture of five bacterial strains in the prevention of chronic skin inflammation
Methods: Hairless SKH-1 mice received daily oral treatment with the probiotic mixture at
the dose of 1x109 Colony-Forming Unit (CFU)/day (or vehicle) for three weeks. Chronic
skin inflammation was induced by repeated applications of 12-O-tetradecanoylphorbol-13-
acetate (TPA; control mice received acetone). Macroscopic and microscopic evaluations of
skin lesions were performed and serum levels of interleukin (IL)-1β, IL-6, tumor necrosis
factor (TNF)-α, IL-17, IL-22, IL-10 and IL-4 measured at the end of the study.
Results: Treatment with the probiotic mixture significantly limited the induced chronic skin
inflammation at both the macroscopic and microscopic levels. This limitation was consistent
with downregulated levels of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, IL-
17 and IL-22) and up-regulated levels of the anti-inflammatory cytokines, IL-10 and IL-4.
Conclusion: The results suggest that the probiotic mixture tested could help in preserving
skin integrity and homeostasis and that its use could be beneficial in dermatological conditions
such as atopic dermatitis and psoriasis.