肠上皮细胞紧密连接在肠屏障中的作用研究进展

Qingchang Suppository up-regulates the expression of tight junction proteins ZO-1 and occludin in experimental ulcerative colitis in rats

AIM: To observe the effect of Qingchang Suppository (QS) on the expression of tight junction proteins zonula occluden-1 (ZO-1) and occludin in the colon of rats with trinitrobenzenesulfonic acid (TNBS)-induced ulcerative colitis (UC).

METHODS: Thirty-six SD rats were randomly and equally divided into six groups: normal control group, model group, SASP group, high-, medium- and low-dose QS groups. UC was induced in rats with TNBS. The expression of tight junction proteins ZO-1 and occludin in the colon was examined by immunofluorescence.

RESULTS: The immunofluorescence signals of ZO-1 and occludin were irregularly distributed and appeared disrupted in rats with UC. The average optical density of ZO-1 and occludin immunofluorescence, as calculated using image analysis software, were decreased obviously in UC rats compared to normal controls (1.802 ± 1.304 vs 3.145 ± 0.110; 0.568 ± 0.063 vs 1.538 ± 0.220, both P < 0.01). Treatment with QS up-regulated the expression of ZO-1 and occludin in rats with UC (both P < 0.01).

CONCLUSION: QS exerts a beneficial effect against TNBS-induced UC in rats possibly by modulating intestinal mucosal barrier and decreasing increased intestinal permeability.

Role of andrographolide in the permeability of intestinal tract of cirrhosis rats and its clinical significance

AIM: To detect the impact of andrographolide on the permeability of intestinal tract of cirrhosis rats by high performance liquid chromatography and to probe its clinical significance.

METHODS: The discharge rate of mannitol (M) and lactulose (L) in cirrhosis rats was detected by high performance liquid chromatography (HPLC) and compared with the standard curve.

RESULTS: The lactulose/mannitol (L/M) discharge rate in cirrhosis rats was significantly higher than that in normal rats (0.036 ± 0.012 vs 0.026 ± 0.009, P < 0.05) and significantly lower in the andrographolide and norfloxacin intervention group than that in the control group (0.022 ± 0.010, 0.022 ± 0.007 vs 0.036 ± 0.012, P < 0.05).

CONCLUSION: The permeability of intestinal tract of cirrhosis rats is significantly higher than that of normal rats and significantly lower in the andrographitis and norfloxacin intervention group than that in the control group.