Probiotic therapy to men with incipient arteriosclerosis initiates increased bacterial diversity in colon: a randomized controlled trial

Objective: This study aimed to clarify the microbial change in the intestinal microbiota in patients, with cardiovascular disease, consuming a drink with high numbers of live Lactobacillus plantarum.

Methods: Sixteen males, with atherosclerotic plaque on the carotid wall, were randomly selected from a larger cohort and included in this double blind, placebo controlled study. Colonic biopsies, taken before and after four weeks of probiotic treatment, were analysed with Terminal Restriction Fragment Length Polymorphism, including digestion with MspI and HaeIII. Microbial diversity was calculated, short-chain fatty acids in faeces, and blood markers were analysed.

Results: Consumption of one probiotic strain of L. plantarum (DSM 9843) increased intestinal microbial diversity. The probiotic group had an increased diversity after consumption of the probiotic drink compared to the change in the placebo group when Shannon and Weaner diversity index (MspI and HaeIII, p=0.026) and Simpson index of diversity (MspI, p=0.044 and HaeIII, p=0.026) were calculated. The fermentation pattern of short-chain fatty acids in faeces were unaffected for most acids, but the probiotic group had decreased concentration of isovaleric acid (p=0.006) and valeric acid (p=0.029). Viable count of lactobacilli increased in the probiotic group (p=0.001), but no significant changes in blood markers were observed.

Conclusion: Administration of a single-strain probiotic increases the bacterial diversity in the gut, and affects the concentration of some short-chain fatty acids. Consumption of the single strain L. plantarum DSM 9843 might be a strategy to favour a diverse intestinal microbiota, which is beneficial for the host.