Objective To generate and characterize natural killer cell (NK cell)-conditional Cd226 gene knockout mice using Cre-loxP technology, and to explore the role of CD226 on NK cells in alleviating intestinal inflammation in a murine model of ulcerative colitis (UC). Methods NK cell-conditional Cd226 gene knockout mice were generated by crossing loxP-flanked Cd226 mice with Ncr1-Cre mice via the Cre-loxP system. Polymerase chain reaction (PCR) and agarose gel electrophoresis were used for genotyping. A UC model was established by dextran sulfate sodium (DSS) induction. Flow cytometry was performed to analyze CD226 expression levels on NK cells and the infiltration of related immune cells in colon tissues. Hematoxylin-eosin (HE) staining was performed to assess the degree of colonic inflammation. Results DNA gel electrophoresis and flow cytometry confirmed the successful generation of NK cell-specific Cd226 knockout mice. After conditional knockout of Cd226 in NK cells, inflammation in the UC mouse model was alleviated. Flow cytometry results showed a reduced proportion of NK cells in peripheral blood and the colon lamina propria, while HE staining demonstrated attenuated inflammatory responses. Conclusion Specific knockout of Cd226 in NK cells mitigates intestinal inflammation in UC mice by reducing NK cell numbers and inhibiting their pro-inflammatory functions.
Animals ; Colitis, Ulcerative/pathology* ; Killer Cells, Natural/metabolism* ; Mice, Knockout ; T Lineage-Specific Activation Antigen 1 ; Antigens, Differentiation, T-Lymphocyte/genetics* ; Mice ; Disease Models, Animal ; Mice, Inbred C57BL ; Male

Objective:To explore therapeutic efficacy and mechanism of puerarin(PUE)in treating of ulcerative colitis(UC).Methods:Network pharmacology and molecular docking technique were used to screen and analyze targets of PUE in regulating UC.C57BL/6 mice were given free access to 2.5%DSS aqueous solution for 7 days,and influence of PUE on changes in body weight and disease activity index(DAI)score were subsequently observed.Histopathological alterations of colon tissue were observed by HE staining,changes of goblet cell population in colon tissue were evaluated through Alcian blue staining;expressions of inflammatory factors in colon tissue were detected by qRT-PCR and ELISA.Effect of PUE on MODE-K cell viability and apoptosis were assessed by CCK-8 and flow cytometry.Results:A total of 38 common targets of PUE in modulating UC,such as AKT1,TNF,STAT3,CASP3,HIF1A and etc,mainly involving TNF,IL-17 and PI3K-Akt signaling pathway.In vivo experiments confirmed that PUE ameliorated degree of colon shortening,body weight and DAI scores and reduced inflammatory cell infiltration in mice.Besides,expressions of inflammatory factors in colon,such as TNF-α and IL-1β,were inhibited by PUE.Furthermore,in vitro experiments validated that PUE relieved DSS-induced apoptosis of epithelial cells.Conclusion:PUE alleviates occurrence and development of DSS-induced UC in mice.