Objective: To observe the effects of Jinqi Jiangtang Tablet, a compound Chinese herbal medicine, on serum matrix metalloproteinase-9 (MMP-9) level and MMP-9 expression in peripheral blood monocytes of rats with streptozocin-induced diabetes.
Methods: Thirty Wistar rats were randomly divided into 3 groups: control group, untreated group and Jinqi Jiangtang Tablet group. Diabetes in rats was induced by a single intraperitoneal injection of streptozocin (70 mg/kg body weight). After model building, rats in the Jinqi Jiangtang Tablet group were administered with Jinqi Jiangtang tablets at a dose of 0.8 g/(kg·d) for 6 weeks and rats in the control group and the untreated group were treated with normal saline. After treatment, level of fasting serum glucose was detected by hexokinas method; serum MMP-9 level was tested by enzyme-linked immunosorbent assay; MMP-9 expression in peripheral blood monocytes was measured by reverse transcription-polymerase chain reaction and Western blot method.
Results: After treatment, fasting serum glucose level in the Jinqi Jiangtang Tablet group was less than that in the untreated group (P<0.05). After modeling, the serum MMP-9 level of rats in the untreated group was (9.11±3.55) μg/L and that in Jinqi Jiangtang Tablet group was (8.97±3.07) μg/L, which were higher than that in the control group ((4.39±1.44) μg/L) (P<0.01). After gavage, the level of serum MMP-9 was lower in Jinqi Jiangtang Tablet group than in the untreated group (P<0.05). The expression of MMP-9 in peripheral blood monocytes in the untreated group was higher than that in the control group (P<0.05). The MMP-9 expression in peripheral blood monocytes of rats with diabetes was down-regulated by Jinqi Jiangtang Tablet (P<0.05).
Conclusion: Jinqi Jiangtang Tablet can decrease the level of serum MMP-9 and down-regulate the MMP-9 expression in peripheral blood monocytes at both mRNA and protein levels in rats with diabetes.

Key words: drugs,Chinese herbal, diabetes mellitus, matrix metalloproteinase-9, rats