Cardiometabolic benefits of Lacticaseibacillus paracasei 8700:2: A randomized double-blind placebo-controlled trial.

Background & Aims: Modulating microbial metabolism via probiotic supplementation has been proposed as an attractive strategy for the prevention of cardiometabolic diseases. Recently, Lacticaseibacillus paracasei (L. paracasei) was reported to alleviate metabolic disorders in murine models, however, its beneficial effects in humans remain to be determined. This study evaluated whether L. paracasei supplementation could improve endothelial function and cardiometabolic health in subjects with metabolic syndrome (MetS).

Methods: In this randomized, double-blind and placebo-controlled trial among 130 participants with MetS, subjects were randomly assigned to placebo or L. paracasei 8700: 2 (10 billion CFU) daily for 12 weeks. Endothelial function was measured by flow-mediated slowing, and cardiometabolic health was determined by both components and severity of MetS. Ideal compliance was defined as consumption no less than 70% of the capsules.

Results: 130 individuals (mean [SD] age, 45.97 [7.11] years; 95 men [73.1%]) were enrolled and randomized to L. paracasei (n = 66) or placebo control (n = 64). Compared to placebo, L. paracasei supplementation led to a greater reduction in remnant cholesterol (-0.16 mmol/L, 95%CI: -0.29 mmol/L to -0.02 mmol/L; P = 0.024). Such a reduction in remnant cholesterol was significantly associated with improvement in endothelial function (r = -0.23, P = 0.027). In subjects with an ideal compliance with trial protocol, L. paracasei treatment additionally lowered triglycerides, alleviated MetS severity and delayed weight gain. On the contrary, no obvious effect on insulin sensitivity or pancreatic beta-cell function was observed after L. paracasei intervention. Moreover, regarding safety and tolerability, no significant between-group difference in protocol-specified adverse events of interest was observed.

Conclusions: L. paracasei supplementation enhanced endothelial function potentially through downregulating remnant cholesterol levels. Our study provides a feasible and safe strategy for the prevention of cardiometabolic diseases in subjects with severe dyslipidemia and endothelial dysfunction.

Registered: Under ClinicalTrails.gov identifier NCT05005754.