核心蛋白聚糖基因治疗肾功能衰竭大鼠的实验研究

Effect of the gene therapy of decorin on progression to experimental renal interstitial fibrosis

目的 利用已转染核心蛋白聚糖(DCN)的成纤维细胞可表达DCN,以中和肾功能衰竭(肾衰)大鼠肾组织内增高的TGF-β1活性,探索基因治疗肾功能不全的新途径。方法 选用雄性SD大鼠在无菌条件下采用5/6肾脏大部分切除。假手术组(A组)6只,5/6肾切除肾衰大鼠模型建立后随机分组,手术对照组(不予任何处理,为B组)10只,空白对照组[成纤维细胞FB(LXSN)细胞处理组,为C组110只,治疗组[FB(LDCNSN)细胞处理组,为D组]10只。4周后观察体重、血脂、肾功能、肾组织病理学变化,并应用免疫组织化学方法检测肾组织内TGF-β1和DCN的表达。结果 经不同处理4周后,各组大鼠在体重和血脂方面各组之间差异无显著性意义。D组大鼠BUN、Scr水平与C组相比有显著下降(P<0.05),而与其基础值相比较虽有所升高,但差异无显著性意义。D组肾衰大鼠4周后,DCN在肾组织内的表达明显增加,与各组比较,差异有显著性意义;而TGF-β1的表达与B组和C组比较差异无显著性意义。同时,病理上也显示D组大鼠肾间质损害明显减轻,与B组和C组比较,差异有显著性意义。结论 通过转染DCN的成纤维细胞转导至肾脏,可在肾脏局部表达DCN。高表达的DCN可改善肾纤维化,延缓肾衰的进程。

Objective To explore the new way of gene therapy to renal dysfunction. Methods FB(LDCNSN) cells,fibroblasts which contain the decorin(DCN) gene,were used to express the DCN to neutralize the higher activity of TGF-β1 in the kidneys with renal interstitial fibrosis. SD rats with 5/6 renal ablation were used as animal models. They were divided into three groups: no treatment group,FB(LXSN) treatment group and FB(LDCNSN) treatment group. FB(LXSN) cells,fibroblasts which contain the control plasmid,were used as control. The FB(LXSN) and FB(LDCNSN) cells were directly injected into the kidneys respectively. Another group was performed shamed-operation.Body weight,serum lipid,renal function and kidneys were collected before the experiment and 4 weeks later. Expression of TGF-β1 and DCN in renal tissue was also studied by immunohistochemical staining. Results Four weeks later,body weight and serum lipid were increased in all groups,but there were no significant differences between the four groups. BUN and Scr levels in FB(LDCNSN) treatment group returned to normal levels. But in the no-treatment group and FB(LXSN) treatment group,BUN and Scr levels increased gradually. There were significant differences in renal function between the FB(LDCNSN) group and other two groups. In kidneys, the damaged renal interstitium was improved in FB(LDCNSN) group. There were significant differences in the degree of renal interstitial fibrosis between FB(LDCNSN) group and other two groups. The expression of DCN increased in FB(LDCNSN) treatment group compared with no treatment group and FB(LXSN) group. Expression of TGF-β1 elevated in all animal models and there were no significant differences among four groups. Conclusions The balance of TGF-β1 and DCN can be changed by transferring DCN gene to kidney to increase the expression of DCN. DCN can improve the renal interstitial fibrosis and slow the progression of renal failure.