Bifidobacterium Infantis Ameliorates Chemotherapy-Induced Intestinal Mucositis Via Regulating T Cell Immunity in...

Area of Science:

• Gastroenterology
• Oncology
• Immunology
• Microbiology

Background:

• Chemotherapy often causes intestinal mucositis (IM), a debilitating side effect for cancer patients.
• Colorectal cancer (CRC) models are crucial for studying IM and potential therapeutic interventions.

Purpose of the Study:

• To investigate the efficacy of Bifidobacterium infantis (B. infantis) in mitigating chemotherapy-induced intestinal mucositis (IM).
• To explore the impact of B. infantis on T cell subsets in a rat model of colorectal cancer (CRC).

Main Methods:

• A colorectal cancer (CRC) model was established in Sprague-Dawley rats using dimethyl hydrazine (DMH) and SW480 cells.
• Rats were divided into Control, Chemotherapy (5-FU+Oxaliplatin), and B. infantis (B. infantis + 5-FU+Oxaliplatin) groups.
• Intestinal mucositis (IM) was assessed via diarrhea severity, gut morphology, pro-inflammatory cytokines (IL-6, IL-1β, TNF-α), and T cell subsets (Th17, Tregs) using RT-PCR and flow cytometry.

Main Results:

• B. infantis administration improved body weight and intestinal villus height while maintaining crypt depth compared to chemotherapy alone.
• B. infantis significantly reduced elevated levels of IL-6, IL-1β, and TNF-α.
• B. infantis modulated T cell responses by decreasing Th1/Th17 related cytokines and increasing CD4+ CD25+ Foxp3+ Tregs in mesenteric lymph nodes.

Conclusions:

• Bifidobacterium infantis (B. infantis) effectively attenuates chemotherapy-induced intestinal mucositis (IM).
• B. infantis exerts its protective effects by suppressing Th1 and Th17 immune responses.
• The probiotic promotes an increase in regulatory T cells (Tregs), contributing to the resolution of IM.