Effect of TrkB-PLC/IP3 pathway on intestinal inflammatory factors and enterocyte apoptosis in mice with colitis

Abstract Background This study aimed to explore the effect of TrkB-PLC/IP3 pathway on intestinal inflammatory factors and enterocyte apoptosis in mice with colitis.Methods Forty 8-week SPF C57BL/6J mice were randomly and averagely divided into normal group (healthy mice), control group (sham-operated mice), model group (model mice without any treatment), and K252a group (model mice with the treatment of 100 μmoL/kg TrkB-PLC/IP3 pathway inhibitor for 5 d before clysis). Mice in model and K252a groups were used to establish ulcerative colitis models after medication.Results There were no significant changes of the content of serum tumor necrosis factor-α (TNF-α) and TNF-γ and protein expressions of TNF-α and TNF-γ in the colon tissues (all P >0.05), a significant increase of disease activity index, colon mucosa damage index, tissue damage index scores, content and protein expressions of serum interleukin-4 (IL-4) and IL-8, and a significant decrease of content and protein expressions of serum IL-10 (all P <0.05) in model and K252a groups, as compared to normal and control groups. Mice in model and K252a groups had blocked enterocyte cycle progression, raised apoptosis ratio, significantly increased mRNA and protein expressions of Caspase3, Bax, FasL and Fas, and significantly reduced mRNA and protein expressions of p-TrkB, PLC-γ1, IP3 and Bcl-2 (all P <0.05). Moreover, intestinal inflammation and apoptosis induced by colitis in K252a group became more aggravated through the inhibition of TrkB-PLC/IP3 pathway activity.Conclusions Inhibition of TrkB-PLC/IP3 pathway can promote the expression of intestinal inflammatory factors and enterocyte apoptosis in mice with colitis.