Objective

To study the mechanism of preventing proteinuria by traditional Chinese medicine YSGJD in early diabetic nephropathy (DN) in rats.

Methods

The male Sprague-Dawley (SD) rats were randomly divided into three groups: normal control, untreated control and treated groups. Experimental diabetes mellitus (DM) was induced in untreated control and treated rats with streptozotocin (STZ), and the normal group was given equal buffer solution. The treated rats were given YSGJD daily. The other two groups were given running water. Eight weeks later,the rats were raised in metabolic cages for 24 hours. Then, the 24 h urinary protein, serum glucose and nitric oxide (NO) were measured. In the renal cortex, the levels of iNOS mRNA and cGMP were determined by reverse transcription-polymerase chain reaction (RT-PCR) and radioimmunoassay separately.

Results

Compared with normal control, in DN rats, the 24 h urine protein, the levels of renal cortex iNOS mRNA and cGMP were increased significantly (P<0.01). All above in treated group were reduced than in untreated control (P<0.05). The serum glucose and NO were increased in DN rats than in normal control (P<0.01), and had a little decrease in the treated group, with no significance between untreated and treated groups.

Conclusion

This recipe can diminish the urine protein in early DN without the significant decrease of serum sugar, can correct the abnormal levels of iNOS mRNA and cGMP in renal cortex. Interfering with the function of NO may be one of its mechanisms.

Key words: diabetic nephropathy, proteinuria, nitric oxide, therapy, TCM