[Effects of acupotomy therapy on macrophage polarization and inhibition of synovial inflammation in rabbits with knee osteoarthritis based on the Notch1/Jagged1/Hes1 signaling pathway].

Abstract

Objectives: To observe the effects of acupotomy therapy on synovial inflammation, macrophage polarization, and protein expressions of drosophila double-wing edge notch homologous gene 1 (Notch1)/Jagged typical Notch ligand 1 (Jagged1)/Hes family BHLH transcription factor 1 (Hes1) signaling pathway, so as to explore its mechanisms underlying improvement of knee osteoarthritis (KOA).

Methods: Male New Zealand rabbits were randomly divided into the blank, model and acupotomy groups (8 rabbits in each group). The KOA model was established by immobilizing the left hind limb in an extended position using a modified Videman method with a plaster cast for 6 weeks. After modeling, 3 meridian lesion points with significant reactions were selected from "Hedingci", "Binwaishang" "Binneishang" "Chengfeijian" "Weiyangci" and "Yinlingci" for acupotomy treatment, once a week for a total of 4 times. X-ray detection was performed after modeling. Behavioral changes in the affected knee joint of the rabbits were observed before and after the intervention and the Lequesne MG scores were recorded. Histopathological changes in the synovial tissue of the left knee joint of rabbits were observed and pathological scores were recorded after HE staining. The positive expressions of cluster differentiation 86 (CD86) and macrophage mannose receptor-1 (CD206) in the synovial tissue were detected by immunohistochemical staining. The mRNA expression levels of inducible nitric oxide synthase (iNOS), CD206, Jagged1, Notch1, arginase-1 (Arg-1) and Hes1 in the synovial tissue were detected by real-time qPCR, and the protein expression levels of Jagged1, Notch1, Arg-1, and Hes1 were detected by Western blot.

Results: Compared with the blank group, the knee joint space of rabbits in the modeling group was significantly narrowed. Compared to the blank group, the model group showed significant increase in Lequesne MG scores (P<0.01), pathological scores (P<0.01), the positive expressions of CD86 and the mRNA expression levels of iNOS (P<0.01), the mRNA and protein expression levels of Notch1, Jagged1 and Hes1 (P<0.01, P<0.05) in synovial tissue;and a decrease in the positive expression of CD206 (P<0.01), the expression levels of CD206 mRNA, and Arg-1 mRNA and protein (P<0.01, P<0.05). After acupotomy intervention, modeling induced increase and decrease indexes mentioned above were reversed (P<0.01, P<0.05).

Conclusions: Acupotomy can reduce the inflammatory response in synovial tissue of KOA rabbits by regulating the Notch1/Jagged1/Hes1 signaling pathway and promoting the polarization shift of synovial macrophages from M1-type to M2-type. This may be one of the mechanisms by which acupotomy treats KOA.