Inhibitory Effect of Lactobacillus plantarum CQPC06 Isolated from Sichuan Pickles on Colitis

Lactobacillus plantarum CQPC06 (LP-CQPC06) is a newly discovered lactic acid bacteria. Here, its protective effects on dextran sulfate sodium-induced colitis in C57BL/6J mice were investigated. LP-CQPC06 was found to have stronger acid and bile salt-resistant activities than L. delbrueckii subsp. bulgaricus (LB). Results from mouse experiments showed that LP-CQPC06 decreased the colon weight/length ratio and increased the colon length in untreated mice, and the effects were better than those of LB. LP-CQPC06 also reduced the serum levels of interleukin 8 (IL-8), IL-1, tumor necrosis factor alpha, macrophage inflammatory protein-1 alpha and also could reduce the colonic tissue levels of myeloperoxidase (MPO), nitric oxide (NO) in colitis mice in colon tissue, meanwhile, these reducing effects were stronger than LB. Quantitative polymerase chain reaction and western blot analyses showed that LP-CQPC06 upregulated the mRNA and protein expression of neuronal nitric oxide synthase, endothelial nitric oxide synthase, nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha; and downregulated the expression of inducible nitric oxide synthase, nuclear factor kappa-beta, C-X-C motif chemokine receptor 1 (CXCR1), and CXCR2. The results of this study showed that L. plantarum CQPC06 had good preventative effects on colitis through the IL-8 pathway. L. plantarum CQPC06 could be used as a probiotics for colonic protection.