Effect of Schizonepetae Herba and Saposhnikoviae Radix on expression of AQP4 and AQP8 in colonic mucosa of rats with ulcerative colitis / 中国中药杂志

ABSTRACT

The aim of this paper was to investigate the effect of Schizonepetae Herba and Saposhnikoviae Radix(wind medicine) on the expression of AQP4 and AQP8 in colonic mucosa in rats with ulcerative colitis(UC). A total of 35 healthy SD male rats were randomly divided into normal group(gavaged with normal saline), DSS model group, as well as low, middle, and high dose wind medicine groups(Schizonepeta and Saposhnikovia 1∶1, gavaged at dosages of 6, 12, and 24 g·kg~(-1)·d~(-1)), with 7 in each group. UC rat model was established by free drinking of 3% dextran sulphate sodium(DSS) solution for 10 days. At the end of the 10 th day after the treatment, mice were put to death to collect colonic mucosa. The length of colon was measured; the colonic mucosal injury index(CMDI) and pathological changes of colon were observed. ELISA method was used for measuring the content of serum IL-1, IL-8, and immunohistochemical method was used to measure AQP4, AQP8 protein expressions in colon mucosa. The expressions of AQP4, AQP8 mRNA were measured by Real-time PCR. As compared with the normal group, the length of colon tissue was significantly reduced(P<0.01), CMDI scores and pathological scores were significantly increased(P<0.01), the levels of serum IL-1 and IL-8 were significantly increased(P<0.05) in model group; the immunohistochemical results showed that the protein expressions of AQP4, AQP8 were lower; the color was light yellow or brown; AQP4, AQP8 mRNA expressions in colon mucosa were significantly decreased in model group(P<0.01). CMDI scores, pathological scores, and the levels of serum IL-1, IL-8 in high, middle, low dose wind medicine groups were obvious lower than those in the model group(P<0.01 or P<0.05); the protein expressions of AQP4, AQP8 were higher; the color was chocolate brown or dark brown; the length of colon tissue, and the expressions of AQP4, AQP8 mRNA were obvious higher in wind medicine groups(P<0.01 or P<0.05). Schizonepetae Herba and Saposhnikoviae Radix could significantly improve the symptoms and histopathology of UC model rats and accelerate the intestinal mucosal healing. The mechanism may be related with up-regulating the expression level of AQP4 and AQP8 in colonic mucosa.