Breast-Milk Lactobacillus Gasseri FN136 Alleviates DSS-Induced Ulcerative Colitis Through Microbiota-Independent...

Area of Science:

• Microbiology
• Immunology
• Gastroenterology

Background:

• Ulcerative colitis (UC) is a chronic inflammatory condition of the colon with increased colorectal cancer risk.
• Probiotics are explored as adjunctive therapies for UC management.

Purpose of the Study:

• To evaluate the efficacy of Lactobacillus gasseri FN136, a breast-milk-derived probiotic, as an intervention for ulcerative colitis.
• To elucidate the mechanism of action of FN136 in mitigating colitis.

Main Methods:

• In vitro assessment of FN136's anti-inflammatory properties, tolerance, and antimicrobial activity.
• In vivo study using a DSS-induced colitis model in mice, with daily oral administration of FN136.
• Analysis of serum markers, immune cell populations, colonic histology, and systemic inflammation markers.
• 16S rRNA sequencing to assess changes in gut microbial composition.

Main Results:

• FN136 demonstrated in vitro anti-inflammatory properties and tolerance.
• In vivo, FN136 significantly attenuated DSS-induced UC, reducing disease activity, weight loss, and colonic damage.
• FN136 restored serum L-arginine, increased splenic regulatory T cells, and elevated nitric oxide production.
• Systemic inflammation markers (IL-6, MPO, LPS, FITC-dextran) were significantly reduced.
• No significant alterations in global microbial composition were observed via 16S rRNA sequencing.

Conclusions:

• Lactobacillus gasseri FN136 mitigates DSS-induced UC through a microbiota-independent postbiotic-host axis.
• FN136 restores serum arginine and enhances immune-barrier homeostasis, offering a novel approach for UC intervention.