Immunomodulatory effects of live and UV-killed Bacillus subtilis natto on inflammatory response in human colorectal adenocarcinoma cell line in vitro

Parisa Abedi Elkhichi; Masoumeh Aslanimehr; Amir Javadi; Abbas Yadegar

doi:10.18502/ijm.v16i4.16301

Parisa Abedi Elkhichi Medical Microbiology Research Center, Qazvin University of Medical Sciences, Qazvin, Iran
Masoumeh Aslanimehr Medical Microbiology Research Center, Qazvin University of Medical Sciences, Qazvin, Iran
Amir Javadi Department of Statistics, Qazvin University of Medical Sciences, Qazvin, Iran
Abbas Yadegar Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran

DOI: https://doi.org/10.18502/ijm.v16i4.16301

Keywords: Bacillus subtilis; Probiotics; Gene expression; Colorectal neoplasms; Immunomodulation

Abstract

Background and Objectives: Colorectal cancer (CRC) is a heterogeneous disease of the colon or rectum arising from adenoma precursors and serrated polyps. Recently, probiotics have been proposed as an effective and potential therapeutic approach for CRC prevention and treatment. Probiotics have been shown to alleviate inflammation by restoring the integrity of the mucosal barrier and impeding cancer progression.

Materials and Methods: In this study, we aimed to investigate the immunomodulatory effects of live and UV-killed Bacillus subtilis natto on the inflammatory response in CRC. Caco-2 cells were exposed to various concentrations of live and UV- killed B. subtilis natto, and cell viability was assessed using MTT assay. Gene expression analysis of IL-10, TGF-β, TLR2 and TLR4 was performed using RT-qPCR.

Results: Our findings showed that both live and UV-killed B. subtilis natto caused significant reduction in inflammatory response by decreasing the gene expression of TLR2 and TLR4, and enhancing the gene expression of IL-10 and TGF-β in Caco-2 cells as compared to control group.

Conclusion: The results of this study suggest that live and UV-killed B. subtilis natto may hold potential as a therapeutic supplement for modulating inflammation in CRC.