Gut Microbiota Manipulation by Probiotic <i>Lacticaseibacillus paracasei DG I1572</i> as New Therapeutical Strategy to Counteract Vascular Inflammaging

The present study investigated the potential beneficial effect of probiotic Lacticaseibacillus paracasei DG I1572 (L. paracasei DG I1572) in a murine model of vascular inflammaging. Aged (40-weeks-old) and young (10-weeks-old) Sprague-Dawley rats were treated with L. paracasei DG I1572 for 3 months. Vascular functions were assessed by pressurized myography, while intravascular ROS and NO production, as well as inflammatory parameters (IL-1β, IL-6, IL-10, and TNF), were measured using dihydroethidium, 4-amino-5-methylamino-2',7'-difluorofluorescein dyes, and ELISA, respectively. Malondialdehyde (MDA) and claudin-1 were examined. Old rats showed: (1) vascular endothelial dysfunctions due to a reduced NO availability; (2) increase in intravascular ROS, (3) the presence of systemic inflammation and oxidative stress, as documented by increased plasma levels of IL-6 and MDA, respectively; (4) a slight decrease in claudin-1 colonic expression, as compared with young rats. Treatment with L. paracasei DG I1572 in old rats improved: (1) endothelial function, increasing NO bioavailability; (2) systemic and in situ oxidative stress in vessels, reducing MDA and intravascular ROS production, respectively; (3) inflammatory parameters, reducing IL-1β and IL-6 as well as increasing IL-10; (4) colonic expression of claudin-1. L. paracasei DG I1572 supplementation can mitigate the low-grade inflammation, and the vascular dysfunctions associated with age, likely through antioxidant and anti-inflammatory properties.