RESUMEN
ObjectiveTo assess the curative effects of Fangji Huangqi detumescence prescription （FHDP） on synovitis and polarization of synovial macrophages of knee osteoarthritis （KOA） model in rats induced by Hulth method. MethodThirty-six rats were randomly divided into sham operation group， model group， high-dose， medium-dose， and low-dose （29.16， 14.58， and 7.29 g·kg-1） FHDP groups， and loxoprofen sodium （16.2 mg·kg-1） group. KOA model in rats was induced by modified Hulth method. Six weeks after the operation， rats were given high， medium， and low concentrations of FHDP， normal saline （NS）， and loxoprofen sodium according to the group to intervene， and sacrificed after 2-week administration. Synovium and cartilage histopathological changes were observed after hematoxylin-eosin （HE） staining. Flow cytometry （FCM） and immunofluorescence （IF） test were used to evaluate the polarization of M1/M2 macrophages. Immunohistochemistry （IMC） and enzyme-linked immunosorbent assay （ELISA） were used to detect the related protein expression levels of macrophage polarization， such as interleukin-1β （IL-1β）， tumor necrosis factor-α （TNF-α）， interleukin-10 （IL-10）， and matrix metalloproteinase-13 （MMP-13） in joint tissues and serum. ResultCompared with the sham operation group， Krenn and Mankin scores in the model group were significantly increased （P<0.01）. Compared with the model group， Krenn score was decreased in all administration groups （P<0.05， P<0.01）， but there was no significant difference in Mankin score in any administration groups. Compared with the sham operation group， M1/mø （CD38+） ratio in the model group was significantly increased （P<0.01）， and M2/mø （CD206+） ratio in the model group was decreased （P<0.05）. Compared with the model group， M1/mø ratio in the high， medium， and low-dose FHDP groups was decreased （P<0.05， P<0.01）， but M2/mø ratio was increased in all administration groups （the difference had no statistical significance）. Compared with the sham operation group， M1/M2 ratio in the model group was significantly increased （P<0.01）. Compared with the model group， M1/M2 ratio in all FHDP groups was significantly decreased （P<0.01）， and M1/M2 ratio in the high and medium-dose FHDP groups was lower than that in the loxoprofen sodium group （P<0.05）. Compared with the sham operation group， the levels of TNF-α， IL-1β， and MMP-13 in synovium and cartilage of the model group were significantly increased （P<0.01）， the level of IL-10 was significantly decreased （P<0.01）. Compared with the model group， the levels of TNF-α and IL-1β in synovium were decreased in all administration groups （P<0.05）， but the difference of the levels of MMP-13 and IL-10 in synovium had no statistical significance. The level of inflammatory mediators in cartilage was not affected in all administration groups. Compared with the sham operation group， the levels of TNF-α and IL-β in serum of the model group were significantly increased （P<0.01）， the level of IL-10 was decreased （P<0.05）. Compared with the model group， the level of TNF-α in the high-dose FHDP group was decreased （P<0.05）， and the level of IL-10 was increased in all administration groups （P<0.05， P<0.01）. The difference of the level of IL-β in all administration groups had no statistical significance. ConclusionFHDP attenuated the synovitis of KOA rats. FHDP exert the effect on the releasing of proinflammatory cytokines and MMP by inhibiting the polarization of M1 macrophages in synovium， and had no significant effect on the polarization of M2 macrophages. Modulating the imbalanced polarization of synovial macrophages was a possible mechanism of FHDP on attenuating synovitis and treating KOA.