单侧输尿管梗阻大鼠肾脏岩藻糖基转移酶8的表达变化

目的: 探讨岩藻糖基转移酶8(FUT8)在单侧输尿管梗阻(UUO)大鼠模型肾脏中表达及意义。方法: 90只雄性Wistar 大鼠随机分为正常对照组(control组)、假手术组(sham组)和UUO组,分别在术后1 d、3 d、7 d、14 d和21 d处死,检测各组大鼠肾功能情况;PAS与Masson染色观察大鼠肾间质病理形态学改变;RT-PCR和Western blotting检测各组大鼠肾组织不同时点FUT8 mRNA及蛋白的表达;免疫荧光检测大鼠肾组织不同时点FUT8和活化素受体样激酶5(ALK5)的分布以及表达;免疫组化检测大鼠肾脏纤维连接蛋白(FN)、Ⅰ型胶原(Col I)和α-平滑肌肌动蛋白(α-SMA)表达。结果: 与control组相比,UUO组大鼠血肌酐及尿素氮于术后3 d开始升高(P<0.05),第21 d升至最高(P<0.01);UUO3 d开始肾间质可见明显炎症细胞浸润,14 d出现明显肾小管萎缩,21 d可见明显肾间质纤维化。FUT8的mRNA表达与蛋白水平表达于术后3 d出现上升并随梗阻时间延长逐渐增加(P<0.05),分别于14 d及21 d达到最高峰(P<0.01); ALK5在肾小管的表达与FUT8一致,呈正相关(r=0.87,P<0.05),且两者分布一致,共表达区域随着肾纤维化进展逐渐增加。FN、Col I和α-SMA表达于术后第3 d出现上升并随梗阻时间延长逐渐增加(P<0.05),且与FUT8呈正相关(r=0.80,r=0.76,r=0.89,P<0.05)。结论: 在肾间质纤维化的进展中,FUT8与ALK5表达呈时空一致性升高,可能与肾间质纤维化程度密切相关。

Increased fucosyltransferase 8 expression in rat kidney with unilateral ureteral obstruction

AIM: To investigate the effect of fucosyltransferase 8(FUT8) on rat renal interstitial fibrosis induced by unilateral ureteral obstruction(UUO).METHODS: Ninety male Wistar rats were randomly divided into normal control group(control),sham operation group(sham) and UUO group,and sacrificed on day 1,3,7,14 and 21 after operation.Serum creatinine and urea nitrogen were detected to assess renal function.PAS and Masson staining were used to observe histological changes of the rat kidneys.The time-correlated expression of FUT8 in the kidney was monitored by RT-PCR and Western blotting.The protein expression levels of FUT8 and activin receptor-like kinase 5(ALK5) were determined by immunofluorescence double-staining.Immunohistochemical staining was also used to assess the protein expression of fibronectin(FN),type I collagen(Col I) and α-smooth muscle actin(α-SMA).RESULTS: Compared with control group,serum creatinine and urea nitrogen in UUO group elevated on day 3 after operation(P<0.05) and reached the peak value on day 21 after operation(P<0.01).Renal tubule atrophy and renal interstitial fibrosis were observed in UUO group 7 and 14 days after operation.The mRNA and protein expression levels of FUT8 increased markedly in UUO group on day 3(P<0.05) and reached its peak value on day 14 and 21 after operation(P<0.01).The results of immunofluorescence and immunohistochemistry showed that FUT8 and ALK5 were coexpressed in renal tubulointestitium.FN,Col I and α-SMA were significantly elevated in UUO group(P<0.05),and were positively correlated with the expression of FUT8(P<0.05).CONCLUSION: The expression of FUT8 influences the progress of renal interstitial fibrosis,tubule atrophy and inflammatory cell infiltration in the kidney.