Development of gene therapy for the vascular proliferative diseases by ribozyme targetting TGF-β mRNA

我们设计了针对转化生长因子-β_1m RNA的锤头状核酶，它能切割合成的底物。我们研制了DNA-RNA嵌合核酶，它能显著抑制自发性高血压大鼠(SHR)血管平滑肌细胞(VSMC)的生长。DNARNA嵌合核酶抑制自发性高血压大鼠血管内皮细胞转化生长因子-β_1mRNA和蛋白的表达。嵌合核酶可显著抑制自发性高血压大鼠肾小球系膜细胞转化生长因子-β_1、纤维连接蛋白、I型胶原的表达。在体内实验中，FITC标记的核酶有效地分布在主动脉和肾脏中。DNA-RNA嵌合核酶可显著抑制自发性高血压大鼠肾毛细血管肥厚和肾小球硬化。我们正在将DNA-RNA嵌合核酶应用于猪血管成形术后冠状动脉狭窄的治疗，以确定其治疗效率、剂量和疗程，以开发转化生长因子-β_1的DNA-RNA嵌合核酶作为动脉增生性疾病和肾小球硬化的基因治疗。

We designed hammerhead ribozyme targetting TGF-β_1 mRNA which cleaved the synthetic substrate RNA. We developed DNA-RNA chimeric ribozyme, which significantly inhibited growth of vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR). DNA-RNA chimeric ribozyme inhibited TGF-β_1 mRNA and protein in VSMC from SHR. DNA-RNA chimeric ribozyme significantly suppressed expression of TGF-β_1, fibronectin, collagen type I mRNAs in mesangial cells from SHR-SP. In vivo experiments, FITC-labeled ribozyme was efficiently distributed in aorta and kidney. DNA-RNA chimeric ribozyme considerably inhibited hypertrophy of renal capirally artery and gromerulosclerosis in SHR-SP in vivo. We are appling DNA-RNA chimeric ribozyme on coronary stenosis after angioplasty in pig, by which efficiency, dosage, and period of treatment will be determined to develop the DNA-RNA chimeric ribozyme to TGF-β_1 as a gene therapy for arterial proliferative diseases and gromerulosclerosis.