Protective effect of the riboflavin-overproducing strain Lactobacillus plantarum CRL2130 on intestinal mucositis in mice

•Riboflavin-overproducing bacterium has a protective effect against mucositis.•Riboflavin-overproducing bacterium showed better beneficial effect to pure vitamin.•The effectiveness of chemotherapy was not affected by the bacterium.•Riboflavin-overproducing bacterium has a mechanism against oxidative stress. Intestinal mucositis (IM) is a local inflammatory response that causes alterations of the intestinal structure that in turn affect nutrient absorption and a side effect that is commonly associated with cancer treatments. Lactobacillus plantarum CRL2130 is a riboflavin-overproducing strain that has previously been shown to provide antiinflammatory properties. The objective of this study was to evaluate the effects of this riboflavin-producing strain in a chemically induced murine mucositis model. Mucositis was induced by daily injections of 5-fluororacil (5-FU) after which mice were either given L. plantarum CRL2130, CRL725 (strain from which CRL2130 was derived that does not overproduce riboflavin), or commercial riboflavin twice daily during 6 d of chemotherapy agent injections. The effect of the strains and riboflavin was also evaluated in vitro using Caco-2 intestinal cancer cell cultures to determine if they interfere with 5-FU's anticancer activity. The administration of L. plantarum CRL2130 significantly attenuated the pathologic changes induced by 5-FU in mice such as body weight loss, diarrhea, shortening of villus height, increases in proinflammatory cytokine concentrations, and elevated production of interleukin 10. In vitro assays using Caco-2 cells showed that the effectiveness of 5-FU was not affected by L. plantarum CRL2130 and that this strain exerted an inhibitory mechanism against oxidative stress. These results indicate that the riboflavin-overproducing strain L. plantarum CRL2130 could be useful to prevent mucositis during cancer treatments and would not affect the primary treatment.