Effect of catalpol from the root of rehmannia glutinosa on the expression of inflammatory proteins in synovium of the knee joint in rats with early osteoarthritis / 中国组织工程研究

ABSTRACT

BACKGROUND: Inflammatory transmitters secreted from the synovium may be one of the important factors inducing the onset of knee osteoarthritis, and further exacerbate knee osteoarthritis. OBJECTIVE: To observe the effect of different concentrations of catalpol from the root of Rehmannia glutinosa on the expression of interleukin-1β, galectin 3 and S100A12 in the synovium of the knee joint in rats with early knee osteoarthritis, and to explore the mechanism of catalpol from the root of Rehmannia glutinosa in the treatment of early knee osteoarthritis. METHODS: The 14 of 48 adult male Wistar rats were randomly selected as a normal control group, and the remaining 34 rats were injected with 4% papain and 0.03 mol/L cysteine solution (0.2 mL) into the right knee joint cavity at 1, 4, 7 days after the initialization of the experiment to duplicate the model of early knee osteoarthritis. At 10 days after the initialization of the experiment, 4 rats in each group were randomly selected for histological observation using hematoxylin-eosin staining and validation of the model using Mankin and OARSI grading evaluation. After the model was successfully verified, the remaining 30 rats in the model group were randomly divided into model control group, low-dose group and high-dose group. At 2 days after successful modeling, each treatment group was infused with corresponding drugs at a dose of 0.2 mL/kg, and normal control group and model control group were infused with normal saline, once a day for 28 consecutive days. The synovium of the right knee joint was then taken from rats in each group, and the expression of interleukin-1β, galectin 3 and S100A12 in the rat synovium was detected by ELISA. RESULTS AND CONCLUSION: Mankin score and OARSI grading were significantly higher in the model control group than the normal control group (P < 0.05). The levels of S100A12, interleukin-1β and galectin 3 in the synovium were significantly higher in the model control group than the normal control group (P < 0.01). Compared with the model control group, the levels of S100A12, interleukin-1β and galectin 3 in the synovium was decreased somewhat in the low-dose group (P < 0.05), but significantly decreased in the high-dose group (P < 0.01). Therefore, catalpol from the root of Rehmannia glutinosa can delay the progression of knee osteoarthritis by reducing the level of inflammatory factors in the synovium.