Crocin effects on the anticancer properties of Lactobacillus lactis probiotics against colorectal adenocarcinoma cells

There are numerous potential mechanisms that can account for the propensity of probiotics to prevent the onset of colorectal cancer. These effects include but are not limited to deactivation of cancer-causing agents, competition with harmful bacteria, boosting the immune system, and reducing cell proliferation by controlling apoptosis and cell differentiation. Other benefits include fermenting undigested food and limiting the activity of certain signaling pathways. Research has shown that the gut microbiota is impacted by nutrition, which subsequently affects the metabolomics, thereby establishing a connection between diet, microbiota, and overall health. The objective of this study was to assess the resistance of Lactobacillus lactis to Crocin. The study involved extracting cell-free supernatants from untreated bacteria and bacteria treated with crocin, and then examining their ability to prevent the growth of HCT-116 colon cancer cells. It was proven that L. lactic , when treated with crocin, can effectively fight against various types of harmful bacteria and can survive in acidic conditions. After 48 hours, both CFS and cro-CFS showed a dose-dependent inhibition of HCT-116 cell growth. The half-maximal inhibitory concentration was 97.41 µL/mL for CFS and 72.07 µL/mL for cro-CFS. The results of flow cytometry tests confirmed the MTT assay findings, showing that cro-CFS-treated cells had a higher rate of apoptosis at 46.8% compared to CFS-treated cells at 25.42%. The results were confirmed by qPCR, which showed that the Caspase 9 and BAX genes were upregulated and the BCL-2 expression level was reduced in cells treated with cro-CFS and CFS. Crocin could alter the metabolomics of probiotics present in the gut, potentially impacting their ability to fight cancer.