Protective Effects of Lacticaseibacillus paracasei 63 on DSS-Induced Colitis in Mice

Area of Science:

• Gastroenterology
• Immunology
• Microbiology

Background:

• Ulcerative colitis (UC) is a chronic inflammatory bowel disease.
• UC involves colonic mucosal damage and immune dysregulation.
• Current treatments have limitations, necessitating novel therapeutic approaches.

Purpose of the Study:

• To evaluate the protective effects of Lacticaseibacillus paracasei 63 in a dextran sulfate sodium (DSS)-induced mouse model of ulcerative colitis.
• To investigate the impact of L. paracasei 63 on intestinal inflammation, barrier integrity, gut microbiota, and systemic inflammatory markers.

Main Methods:

• Oral administration of L. paracasei 63 to male ICR mice with DSS-induced colitis.
• Assessment of intestinal inflammation, barrier function markers (TLR4, NF-κB, MLCK), gut microbiota composition, short-chain fatty acid (SCFA) levels, and systemic inflammatory markers (IL-1β, TNF-α).
• Evaluation of primary immune organ indices, including the thymus.

Main Results:

• L. paracasei 63 significantly alleviated colitis symptoms and improved intestinal barrier function.
• Administration reduced TLR4 expression, NF-κB p65 phosphorylation, and MLCK-related markers.
• Modulation of gut microbiota composition, increased SCFA levels (especially acetate), reduced systemic inflammation (lower IL-1β, TNF-α), and an increased thymus index were observed.

Conclusions:

• L. paracasei 63 demonstrates significant ameliorative effects on DSS-induced ulcerative colitis.
• These benefits are linked to enhanced intestinal barrier integrity, improved inflammatory status, beneficial gut microbiota modulation, increased SCFA production, and normalized systemic immune indicators.