Effects of ethanol extracts and compounds from Astragali radix on chondrocytes and MIA-induced osteoarthritis model in rat

Abstract

This work was carried out to evaluate the effects of extract from the radix of Astragalus membranaceus (AR) and the natural product from AR on SW1353 Hyman chondrocytes and monosodium iodoacetate (MIA)-induced osteoarthritis (OA) model in rat. Ethanolic extract (ARE, 100, 200, 400 mg/kg) from AR were orally administered once a day for 14 days after the MIA injection. Administration of ARE to the MIA-induced OA rats decreased significantly knee arthritis scoring. The histopathological analyses showed remarkably that ARE treatment alleviated the severe joint damage such as the loss of necrotic chondrocytes and cartilage erosion in cartilage of MIA-OA model. ARE decreased significantly histopathological scoring to the level of 68.6 and 61.8% at the treatment of 200 and 400 mg/kg of ARE, respectively. ARE and butanol fraction from ARE inhibited the expression of matrix metalloproteinase-13 (MMP-13) mRNA in IL-1β-treated SW1353 cells. Eight compounds isolated from the ethyl acetate fraction of 80% methanol extract were tested for inhibitory effect on the production of MMPs in IL-1β-treated SW1353 cells. Isoastragaloside II revealed the inhibition of 21.3, 16.8 18.8, 8.2 and 23.5% on MMP-1, MMP-3, MMP-13, MMP-2 and MMP-9, respectively, at 10µM treatment, comparing to control. Calycosin exhibited the inhibition of 23.5, 39.8, 13.7, 15.9 and 23.4% on MMP-1, MMP-3, MMP-13, MMP-2 and MMP-9, respectively, at 40µM treatment, comparing to control. These results indicated that ARE might be useful in protecting and alleviating joint damage in OA through preventing chondrocyte injury and extracellular matrix degradation.