Abstract: This study observed the effect of Lactobacillus plantarum KSFY04 (LP-KSFY04) against carrageenan-induced thrombosis in mice by regulating the NF-κB signaling pathway. Commercial biochemical kits and quantitative polymerase chain reaction (qPCR) were used to detect related indexes in mouse serum and tissues, and hematoxylin-eosin (HE) staining was used for histopathological examination. The composition of intestinal microbiota was examined as well. The results showed that LP-KSFY04 could effectively reduce the degree of black tail in thrombotic mice, prolong the activated partial thromboplastin time (APTT), and reduce the prothrombin time (PT), thrombin time (TT) and fibrinogen (FIB) level. LP-KSFY04 could also reduce the levels of inflammatory cytokines including tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6) and interleukin-1 beta (IL-1β) in the serum, kidney and liver of thrombotic mice. Pathological observation showed that LP-KSFY04 could reduce liver and kidney lesions caused by thrombosis and the accumulation of tail vein thrombosis. qPCR results showed that LP-KSFY04 could down-regulate the mRNA expression of nuclear factor kappa-B p65 (NF-κB p65), IL-6, TNF-α, intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin. Moreover, LP-KSFY04 increased the relative abundance of Bacteroidetes, Lactobacillus and Bifidobacterium and decreased the relative abundance of Firmicutes. These results showed that LP-KSFY04 can reduce inflammation and inhibit thrombosis in thrombotic mice, and the effects of high concentration of LP-KSFY04 were most pronounced, which were close to those of dipyridamole.

Key words: thrombus; Lactobacillus plantarum; nuclear factor κB signaling pathway; coagulation; immune