Novel Lactobacillus Strains Alleviate E. coli-induced Inflammation in a Urinary Tract Infection Rat Model

Area of Science:

• Microbiology
• Immunology
• Urology

Background:

• Urinary tract infections (UTIs) are common bacterial infections, often caused by E. coli, significantly impacting quality of life, especially with recurrent cases.
• Antibiotic resistance and side effects necessitate alternative UTI therapies.
• Probiotics are being explored for their potential therapeutic benefits in managing bacterial infections.

Purpose of the Study:

• To investigate the anti-E. coli effects of heat-inactivated Lactobacillus helveticus GUT10 and L. salivarius HHuMin-U, individually and in combination.
• To evaluate the efficacy of these probiotics in mitigating inflammation and infection associated with UTIs in vitro and in vivo.

Main Methods:

• In vitro studies utilized LPS-induced T24 bladder cells to assess the impact of probiotics on inflammatory markers and signaling pathways.
• In vivo studies employed an E. coli-induced UTI rat model to evaluate the protective and therapeutic effects of the probiotic strains.
• Key markers assessed included pro-inflammatory cytokines, COX2, PGE2, NF-κB signaling, ROS production, bacterial load, and mucosal integrity.

Main Results:

• Probiotic treatments significantly suppressed pro-inflammatory cytokines (TNF-α, IL-1β, IL-6), COX2, and PGE2 by inhibiting NF-κB signaling and ROS production in T24 cells.
• In the UTI rat model, both Lactobacillus strains demonstrated significant protective and therapeutic effects, reducing bladder and urethral mucosal damage.
• Treatments led to decreased E. coli load in the bladder and urine, alongside an increased presence of lactobacilli in the bladder.

Conclusions:

• Heat-inactivated Lactobacillus helveticus GUT10 and L. salivarius HHuMin-U exhibit potent in vitro and in vivo anti-E. coli activity.
• The probiotic combination effectively reduces inflammation and bacterial load, offering a promising non-antibiotic strategy for UTI prevention and treatment.
• These findings support the development of probiotic-based therapies as a viable alternative to conventional antibiotics for managing UTIs.