OBJECTIVETo investigate the reactive oxygen species (ROS) content and nuclear transcription factor-kappa B expression (NF-kappaB) in renal tissue of diabetic rats and the effect of Astragalus and Arctium in combination on them.

METHODSStreptozotocin (STZ)-induced diabetic model rats were established. Astragalus and Arctium in different dosages (low, moderate, high) were combined after orthogonal design and administered respectively to the model rats via gastrogavage for 4 or 8 weeks. Content of ROS in the renal tissue was detected by flow cytometry and expression of functional NF-kappaB p65 was assessed by Western blot at the 4th and 8th weekends (4th week and 8th week).

RESULTSROS content of renal tissue in the model rats was 36.55 +/- 7.46% at the 4th week and 31.91 +/- 5.83% at the 8th week, NF-kappaB p65 expression was 165.00 +/- 3.14 at the 4th week and 214.00 +/- 5.11 at the 8th week, all higher than those in normal rats (6.21 +/- 1.83% and 129.00 +/- 1.58 at the 4th week, 6.95 +/- 1.41% and 148.00 +/- 2.32 at the 8th week) respectively. The combined use of Astragalus and Arctium showed decreasing effects on both indexes significantly, and the decreasing effects of the combination with moderate and high dose Astragalus were better than those with low dose, with the details as follows: those of ROS at the 4th week were 11.43 +/- 2.42%, 18.37 +/- 7.58% and 22.10 +/- 4.71% for high, moderate and low dose Astragalus combination respectively (same hereinafter), at the 8th week 12.55 +/-4.40%, 19.15 +/- 6.64% and 23.48 +/- 3.13%; and for NF-kappaB p65 expression at the 8th week, 185.00 +/- 6.99, 183.00 +/- 3.89 and 194.00 +/- 4.98 respectively.

CONCLUSIONCombined use of Astragalus and Arctium may ameliorate the condition of diabetic nephropathy by inhibiting the activation of the ROS-NF-kappaB signal passage.