Lactobacillus Plantarum 299v Supplementation Does Not Acutely Improve Endothelium Dependent Vasodilation

Introduction: Endothelial dysfunction is characterized by systemic vasoconstriction, thrombosis, and inflammation. Emerging data suggests that modulation of gut microbiota with probiotics, such as Lactobacillus plantarum 299v ( Lp299v ), is an effective way of reducing systemic inflammation and subsequent endothelial dysfunction. Our group previously showed daily supplementation with Lp299v in men with stable coronary artery disease improved endothelium dependent vasodilation. However, it was unclear if improvement in endothelial function manifests immediately after supplementation, potentially related to the fermentation products consumed with Lp299v , or happens as a result of prolonged supplementation. We therefore set out to assess acute impact of Lp299v supplementation on endothelial dependent vasodilation. Hypothesis: We hypothesized endothelial dependent vasodilation measured at two- and 24-hours would not differ after Lp299v supplementation. Methods: A total of 26 patients (ages 47-74) with a diagnosis of hypertension, hyperlipidemia, diabetes mellitus, peripheral vascular disease, cerebrovascular disease, or cardiovascular disease were randomized, to receive 20 million CFU of Lp299v supplementation contained in 30 mL of the GoodBelly® Straightshot or matching heat-killed placebo. Endothelial function was measured using brachial artery flow mediated dilation (FMD) at baseline, two-, and 24-hours post-intervention. Results: Within the placebo and Lp299v groups, there were no significant differences in resting diameter, FMD, and baseline peak shear between time points. Conclusion: Lp299v supplementation does not produce a significant acute effect on FMD within the first 24 hours of supplementation. This supports the hypothesis that the beneficial effect of Lp299v supplementation is likely a result of long-term supplementation rather than acute effects of concomitant ingestion of fermentation products.