Gut Limosilactobacillus reuteri-secreted Components Mitigate Susceptibility to Radiation by Alleviating Oxidative Stress in the Intestinal Epithelium

Radiotherapy is the most effective method to eliminate several types of cancer; however, radiation-induced intestinal damage, such as epithelial cell apoptosis, remains a perennial problem. The study revealed that the feces of mice surviving exposure to 7.5 Gy ionizing radiation (IR) originally harbored higher levels of Lacticaseibacillus casei, Lactobacillus salivarius (LS), and Limosilactobacillus reuteri (LR) than those in the commensal bacteria of dead mice. While mice pre-inoculated with LS and LR for 8 weeks showed protective efficacy against 7.5 Gy IR, mice pretreated with LR-Secreted Components (LR-SCs) for 7 days demonstrated lesser epithelial damage and susceptibility to high IR doses than those of LS-SC treated mice. LR-SC treatment also regulated the increased levels of IR-induced cellular reactive oxygen species levels in intestinal epithelial cells. In summary, LR-SCs are potential prophylactic agents to alleviate the side effects of radiotherapy in patients with cancer.