Regulatory effects of hedgehog pathway on intestinal epithelial barrier function under hypoxia
10.3760/cma.j.issn.1673-9752.2013.06.016
- VernacularTitle:Hedgehog信号通路在缺氧肠上皮屏障功能调控的作用
- Author:
Guang YANG
;
Xuechao YANG
;
Guoqing CHEN
;
Lihua SUN
;
Hua YANG
- Publication Type:Journal Article
- Keywords:
Hedgehog signal pathway;
Cyclopamine;
Epithelial barrier function;
Transepithelial electrical resistance;
Tight junction proteins
- From:Chinese Journal of Digestive Surgery
2013;(6):465-468
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the regulatory effects of hedgehog pathway on intestinal epithelial barrier function under hypoxia.Methods The IEC-6 cells of rats were divided into 3 groups:the normoxia group (21％ oxygen concentration),the hypoxia group (2％ oxygen concentration) and the hypoxia + cyclopamine group (cells pretreated by 5 mmol/L of cyclopamine,and then exposed in an atmosphere with 2％ oxygen concentration).The mRNA expressions of IHH,PTCH and GLI-1 were detected,and the transepithelial electrical resistance (TER) was determined.The protein expressions of tight junction proteins (ZO-1,Occludin,Claudin-1) and IHH were assayed by using the Western blot.All data were analyzed using the one-way analysis of variance or LSD-t test.Results The relative mRNA expressions of IHH,PTCH and GLI-1 were 0.056 ± 0.009,0.459 ± 0.087,0.142 ± 0.023 in the normoxia group,and 0.303 ± 0.052,0.678 ± 0.073,0.483 ± 0.061 in the hypoxia group,with significant difference between the 2 groups (t =-14.05,-11.85,-6.52,P ＜ 0.05).The relative protein expressions of IHH in the normoxia group and the hypoxia group were 0.39 ±0.06 and 0.91 ±0.15,with a significant difference between the 2 groups (t =-8.08,P ＜ 0.05).The TERs of the normoxia group,the hypoxia group and the hypoxia + cyclopamine group were (134 ± 5) Ohm/cm3,(100 ± 6) Ohm/cm3 and (118 ± 5) Ohm/cm3,with significant difference between the 3 groups (F =1.04,P ＜ 0.05).Compared with the normoxia group,the TER of the hypoxia group was decreased by 27.7％ (t =7.84,P ＜ 0.05) ; compared with the hypoxia group,the TER of the hypoxia + cyclopamine group were increased by 16.4％,but it was still significantly lower than the normoxia group (t =4.23,P ＜ 0.05).The expressions of ZO-1,Occludin and Claudin-1 were 1.18 ± 0.24,0.80 ±0.13 and 0.90 ±0.09 in the normoxia group,and 0.58 ±0.08,0.32 ±0.05 and 0.50 ±0.09 in the hypoxia group,and 0.92 ± 0.21,0.43 ± 0.10 and 0.82 ± 0.11 in the hypoxia + cyclopamine group,with significant difference between the 3 groups (F =4.95,2.88,10.09,P ＜0.05).The expressions of ZO-1,Occludin and Claudin-1 in hypoxia group were decreased by 48.7％,40.0％ and 55.6％ when compared with the normoxia group (t =12.86,9.35,18.90,P ＜0.05).The expressions of ZO-1,Occludin and Claudin-1 in the hypoxia + cyclopamine group were increased by 59.9％,35.2％ and 65.1％ when compared with the hypoxia group (t =5.63,2.92,6.66,P ＜ 0.05).Conclusion Hedgehog signal pathway could be activated under hypoxia,and then the expressions of tight junction proteins are decreased,which finally induces the injury of intestinal epithelial barrier function.
