Zhonghua Nei Ke Za Zhi. 2000 Oct; 39(10): 677-81.

[Isolation of genes associated with renoprotective effects of astragalus and angelica by silver staining mRNA differential display]

Yu L, Wang H, L� Y.

Renal Division, First Teaching Hospital and Institute of Nephrology, Peiking University, Beijing 100034, China.

OBJECTIVE: To isolate genes associated with chronic progression of renal diseases and renoprotective effects of Astragalus and Angelica(A & A). METHODS: Chronic puromycin nephropathy, which is characterized by massive proteinuria and progressive glomerular sclerosis and tubulointerstitial fibrosis, was induced in SD rats by repeated peritoneal injections of puromycin. Rats were randomly divided into three groups: (1) normal control (n = 7), (2) puromycin nephropathy without A&A treatment (n = 7), (3) puromycin nephropathy A & A treatment (3 ml/d, n = 7). After 12 weeks, serum, urine and renal tissue were collected for study. The technique of silver staining mRNA differential display (DD) was used to investigate the changes of gene expression in kidneys of normal and nephropathy with and without A&A treatment rats. Genes expressing differently during the progression of renal diseases were isolated and the progression could be normalized by A&A. RESULTS: Twenty-six candidate cDNA fragments were isolated with DD. Northern blot analysis of eight randomly chosen candidate cDNA fragments demonstrated one exhibiting reduced mRNA expression in the fibrogenic process but upregulated by A&A treatment. Besides kidney, the gene was also expressed in lung, heart, liver and spleen. Whether it takes part in fibrogenic processes of these organs needs further study. Homology analysis through BLAST revealed that this gene was a novel one. CONCLUSION: Silver staining mRNA differential display is a simple and quick technique for isolating differently expressed genes. The downregulated expression of the isolated new gene may contribute significantly to the fibrogenic process and be associated with A&A's protective effects.