Protective Effect Of Collagen Oligopeptide Powder On DSS-Induced Ulcerative Colitis Mice

Objective:Ulcerative colitis(UC)is a chronic nonspecific inflammation of the colorectal mucosa,with an increasing incidence worldwide.The lesions are mainly in the colon and rectum,but can extend to the descending colon or even the entire rectum.In addition,ulcerative colitis is a long-term recurrent disease,clinical manifestations include abdominal pain,diarrhea,pus and blood stool.Collagen oligopeptide powder(CP)is a kind of fish skin collagen made from freeze-dried cod skin.Many studies have shown that collagen oligopeptide powder can inhibit inflammation,resist oxidation and improve immunity.The purpose of this study was to investigate the protective effect of collagen oligopeptide powder on DSS-induced ulcerative colitis mice.Methods:Forty female BABL/ C mice were randomly divided into 5 groups,including control group(no treatment,Control group,model group(DSS),DSS+300mg/kg CP group(DSS+L-CP),DSS+600mg/kg CP group(DSS+M-CP),DSS+900mg/kg CP group(DSS+H-CP).Except the control group,the other four groups were successfully induced intestinal inflammation similar to human ulcerative colitis by drinking 3% DSS solution for 7 days.DSS group was given 0.9% normal saline daily,and treatment group was given CP with different concentration gradients(300/600/900mg/kg)daily by gavage.During molding.Body weight,fecal traits and hematochezia of each mouse were recorded.After modeling,sacrificed mice were used to collect blood and colon tissue.Disease activity index was used to evaluate the severity of colitis in mice according to the data.The anti-inflammatory effects of CP were evaluated by general physical examination,pro-inflammatory cytokine examination,histopathological examination,immunohistochemical examination and inflammatory signaling pathway examination.Results:1.Mice treated with different concentrations of CP showed improved weight loss compared with DSS treated mice.As the experiment progressed,DAI scores in the DDS group gradually increased,but after 4 days,DAI scores in all treatment groups were lower than those in the model group.2.After CP treatment,the level of proinflammatory factors decreased significantly,and the secretion of TNF-α,IL-1β and IL-1 was inhibited.3.Compared with DSS treated mice,CP treated mice showed significant inflammation relief,colon length increased,secretion of pro-inflammatory cytokines decreased,colon wall edema decreased,intestinal gland recovered better than before,goblet cell loss was significantly alleviated,and colon inflammation was significantly reduced.4.CP also induced the increased expression of MKP-1 in mice with ulcerative colitis,thereby reducing the phosphorylation level of MAPKS,and thus slowing down the occurrence and development of inflammation.5.No drug-related lesions were observed in the overall structure of liver,kidney and spleen of mice in low-dose,medium-dose and high-dose groups,which proved that CP had low drug toxicity.Conclusion : CP has a protective effect on DSS induced ulcerative colitis mice,the mechanism may be that CP promotes the expression of MKP-1 and then inhibits the activation of MAPK signaling pathway in colitis.This study suggests that CP has preventive and protective effects on colon inflammation.