Curcumin chitosan microsphere improve ulcerative colitis inflammatory response by regulating miR-224-3p/TLR4 axise

Abstract

Objective To observe the clinical effect of curcumin chitosan microsphere (CCM) on ulcerative colitis. Methods: Our group selected 75 cases with ulcerative colitis (UC) receiving treatment at The First Affiliated Hospital of Nanchang University as observation group, and 75 cases that were healthy and received examination at the same time as control group. We detected serum miR-224-3p, TLR4, TNF-α and NF-κB levels using the double antibody sandwich ELISA (DAS-ELISA). In animal experiments, our team applied DSS to induce IBD mice models, allocated into control group, model group, sulfasalazine group, curcumin group and CCM high dose group, CCM medium dose group, and CCM low dose group, in total 7 groups (n = 10). After molding, on 3rd day our team began intragastric administration for 10 days. On 14th d, we sacrificed the mice, conducted HE staining, observed changes in the pathological form of bowel tissue in each group, and gave inflammation scores. Taking the colon tissue and serum, our team applied ELISA to detect inflammatory factors such as TNF-α, TLR4, IFN-γ levels in supernate of tissue homogenate, as well as performed western blot to detect SDF-1, CXCR4, miR-224-3p protein expression levels in intestinal tissue. Results: TNF-α, TLR4, NF-κB expressions in observation group were signally elevated while miR-224-3p expression visually decreased. In control group, TNF-α, TLR4, NF-κB expressions in observation group were signally decreased while miR-224-3p expression visually elevated, the difference was significant (P < 0.05). After treatment, serum TNF-α, TLR4, NF-κB expressions in sulfasalazine group, curcumin group, CCM low, medium and high dose groups were signally reduced, while IFN-γ expression was elevated significantly, when comparing with those in model control group, the difference was significant (P < 0.01). Compared CCM low, medium and high dose groups with sulfasalazine group, there was a significant difference in efficacy (P < 0.05). Compared CCM low, medium and high dose groups with curcumin group, there was a significant difference in efficacy (P < 0.05). We applied western blot to detect SDF-1, CXCR4, and miR-224-3p protein expression levels, finding that CCM enhanced in SDF-1, CXCR4, and miR-224-3p protein expression levels, with significant differences when comparing with those in model control and curcumin groups. Conclusion: CCM may elevate IFN-γ level and enhance SDF-1, CXCR4, and miR-224-3p protein expression levels through inhibiting TNF-α, NF-κB, and TLR4 expressions, thus reducing inflammatory response as well as damage to colon tissue in mice with UC through anti-inflammatory effects.