Anti-cancer potential of postbiotic metabolites from Lactobacillus plantarum

In this study, researchers from Malaysia evaluated the cytotoxicity of postbiotic metabolites (PM) produced by six strains of Lactobacillus plantarum on various cancer and normal cells. Their findings were published on the journal BMC Complementary and Alternative Medicine.

• L. plantarum is a major species of lactic acid bacteria (LAB) capable of producing PM.
• Studies suggest that these PMs have probiotic effects on rats, poultry and pigs.
• However, their cytotoxicity and anti-proliferative activity have not yet been evaluated.
• For their study, the researchers used normal human primary cells and breast, colorectal, cervical, liver and leukemia cancer cell lines.
• They used different assays to determine the toxicity of PM in vitro.
• Subsequently, they used fluorescent microscopy and flow cytometry to determine the mode of cytotoxicity of a selected PM, UL4 PM, on MCF-7 cells (breast cancer) due to its pronounced cytotoxicity.
• The researchers reported that UL4 PM had the lowest IC50 value against breast cancer cells; RG14 PM against colorectal cancer cells; and RG11 and RI11 PM on leukemia cells.
• They also observed that all tested PMs did not cause hemolysis of human, dog, rabbit and chicken red blood cells, and exhibited no cytotoxic effects on normal breast MCF-10A cells and primary cultured cells like human peripheral blood mononuclear cells, mice splenocytes and thymocytes.
• UL4 PM and RG14 PM exerted anti-proliferative effects on MCF-7 and HT-29 (colorectal cancer) cells, respectively, after 72 hours of incubation at a concentration of 30 percent (v/v). Their cytotoxicity was mediated through apoptosis.

Based on these findings, the researchers concluded that the PMs produced by six strains of L. plantarum are selectively cytotoxic to malignant cancer cells in a strain-specific and cancer cell type-specific manner. These PMs can thus be used as functional supplements and as an adjunct to cancer treatments.

Read the full study at this link.

Journal Reference:

Chuah LO, Foo HL, Loh TC, Alitheen NBM, Yeap SK, Mutalib NEA, Rahim RA, Yusoff K. POSTBIOTIC METABOLITES PRODUCED BY LACTOBACILLUS PLANTARUM STRAINS EXERT SELECTIVE CYTOTOXICITY EFFECTS ON CANCER CELLS. BMC Complementary and Alternative Medicine. 03 June 2019;19(1). DOI: 10.1186/s12906-019-2528-2