敲除Colgalt2基因加重小鼠急性肝损伤

目的：初步探讨Colgalt2基因介导的胶原Glcα1，2 Galβ1?糖基化修饰在急性肝损伤过程中的作用。方法取60只Colgalt2＋／＋小鼠和60只Colgalt2－／－小鼠进行急性肝损伤实验，雌雄各半。每组随机选取20只小鼠腹腔注射CCl4（CCl4∶橄榄油＝2∶7，20 ml／kg）。观察小鼠死亡情况，并绘制生存曲线。每组剩余40只小鼠随机分为0、4、8、12 h组，每组10只，腹腔注射CCl4（剂量同上）。分别于0、4及8 h各处死6只小鼠，之后将4及8 h组剩余的小鼠均纳入12 h组（ Colgalt2＋／＋小鼠， n＝14； Colgalt2－／－小鼠， n＝16），并于12 h处死小鼠。 HE染色观察肝组织的病理学改变，取血清进行生化指标ALT、 AST测定。利用qRT?PCR和Western印迹技术检测小鼠Colgalt2在基因及蛋白水平的表达情况。结果Colgalt2基因在Col?galt2＋／＋小鼠肝组织内表达，而在Colgalt2－／－小鼠肝组织内不表达。注射CCl4后10 h， Colgalt2＋／＋小鼠死亡率为35％， Colgalt2－／－小鼠死亡率为70％，两组小鼠死亡率差异显著（P＜0．05）。注射CCl4后12 h， Colgalt2＋／＋小鼠死亡率达50％， Colgalt2－／－小鼠死亡率为70％，差异不显著（P＞0．05）。肝功检测及HE染色结果均提示，与Colgalt2＋／＋小鼠相比， Colgalt2－／－小鼠肝损伤较重。注射CCl4后，野生型小鼠Colgalt2在RNA水平和蛋白水平表达下调。结论 Colgalt2基因敲除在一定程度上可加重小鼠急性肝损伤。该观察结果提示， Colgalt2基因介导的胶原Glcα1，2 Galβ1?糖基化修饰可能与肝损伤的修复有关。

Colgalt2 Knock-out Exacerbates Acute Liver Injury

Objective To investigate the role of Colgalt2?mediated collagen Glcα1 , 2 Galβ1?glycosylation in CCl4?induced acute liver injury. Methods The C57 BL/6 J mice were divided into two groups: Colgalt2 +/ +mice ( n=60 ) and Colgalt2 -/ - mice ( n=60 ) , half male and half fe?male. Twenty mice were randomly selected from each group and intraperitoneally injected with CCl4 solution (CCl4∶oil 2∶7 (v/v), 20 ml/kg body weight) . The deaths of mice were recorded and the survival curve drawn. Additionally, the rest of mice in each group were divided into four groups:0 h, 4 h, 8 h, 12 h groups, 10 mice in each group. They were treated with CCl4 as mentioned a?bove. Six mice were sacrificed at each time point. The rest mice in 4 h group and 8 h group were brought into 12 h group ( Colgalt2 +/ + mice group, n =14; Colgalt2 -/ - mice group, n =16 ) . Then, all mice were sacrificed at 12 h. The expression of Colgalt2 gene in mice was detected by Western blotting and qRT?PCR. Serum AST and ALT levels were determined and liver tissues of the mice were examined by HE staining. Results Colgalt2 gene was expressed in the liver tissues of Colgalt2 +/ + mice but not in Colgalt2 -/ - mice. The mortality of Colgalt2 +/ + mice was 35% and that of Colgalt2 -/ - mice was 70 % at 10 h after injection of CCl4 and the difference was significant ( P<0. 05) . At 12 h, the mortality of Colgalt2 +/ + mice was 50 %, which was not significantly dif?ferent from that of Colgalt2 -/ - mice ( 70 %) ( P>0. 05 ) . Liver function test and HE staining showed that liver injury in Colgalt2 -/ - mice was severer than that in Colgalt2 +/ + mice. Colgalt2 at the level of RNA and protein was down?regulated after injection of CCl4. Conclusion Colgalt2 gene knock?out may aggravate the liver injury of mice to some extent. Collagen Glcα1 , 2 Galβ1?glycosy?lation mediated by Colgalt2 may be related to the repair of liver injury.