Acupotomy alleviates knee osteoarthritis in rabbit by regulating chondrocyte mitophagy Pink1-Parkin pathway.

OBJECTIVE: To investigate the effect of acupotomy, on mitophagy and the Pink1-Parkin pathway in chondrocytes from rabbits with knee osteoarthritis (KOA). METHODS: A KOA model was established via the modified Videman method. Rabbits were randomly divided into a control group (CON), KOA group and KOA + acupotomy group (Acu). Rabbits in the acupotomy group were subjected to acupotomy for 4 weeks after model establishment. The behavior of the rabbits before and after intervention was recorded. Cartilage degeneration was evaluated by optical microscopy and fluorescence microscopy. The level of mitophagy was evaluated by transmission electron microscopy, immunofluorescence and enzyme-linked immunosorbent assay (ELISA). The expression of phosphatase and tensin homolog (PTEN)-induced kinase 1 (Pink1)-Parkin mitophagy pathway components was evaluated by immunofluorescence, Western blotting and real-time polymerase chain reaction. RESULTS: In rabbits with KOA, joint pain, mobility disorders and cartilage degeneration were observed, the Mankin score was increased, collagen type Ⅱ (Col-Ⅱ) expression was significantly decreased, mitophagy was inhibited, mitochondrial function was impaired, and factors associated with the Pink1-Parkin pathway were inhibited. Acupotomy regulated the expression of Pink1-Parkin pathway-related proteins, the mitophagy-related protein microtubule-associated protein-1 light chain-3, the translocase of the outer membrane, and the inner mitochondrial membrane 23; increased the colocalization of mitochondria and autophagosomes; promoted the removal of damaged mitochondria; restored mitochondrial adenosine-triphosphate (ATP) production; and alleviated cartilage degeneration in rabbits with KOA. CONCLUSIONS: Acupotomy played a role in alleviating KOA in rabbits by activating mitophagy in chondrocytes via the regulation of proteins that are related to the Pink1-Parkin pathway.

Application of Acupotomy in a Knee Osteoarthritis Model in Rabbit.

Knee osteoarthritis (KOA) is one of the most frequently encountered diseases in the orthopedic department, which seriously reduces the quality of life of people with KOA. Among several pathogenic factors, the biomechanical imbalance of the knee joint is one of the main causes of KOA. Acupotomology believes that restoring the mechanical balance of the knee joint is the key to treating KOA. Clinical studies have shown that acupotomy can effectively reduce pain and improve knee mobility by reducing adhesion, contracture of soft tissues, and stress concentration points in muscles and tendons around the knee joint. In this protocol, we used the modified Videman method to establish a KOA model by immobilizing the left hindlimb in a straight position. We have outlined the method of operation and the precautions related to acupotomy in detail and evaluated the efficacy of acupotomy in conjunction with the theory of "Modulating Muscles and Tendons to Treat Bone Disorders" through the detection of the mechanical properties of quadriceps femoris and tendon, as well as cartilage mechanics and morphology. The results show that acupotomy has a protective effect on cartilage by adjusting the mechanical properties of the soft tissues around the knee joint, improving the cartilage stress environment, and delaying cartilage degeneration.

Acupotomy ameliorates subchondral bone absorption and mechanical properties in rabbits with knee osteoarthritis by regulating bone morphogenetic protein 2-Smad1 pathway.

OBJECTIVE: To investigate the effects of acupotomy on the subchondral bone absorption and mechanical properties in rabbits with knee osteoarthritis (KOA). METHODS: The rabbits were divided into blank control, model, acupotomy and electroacupuncture (EA) groups, with 12 rabbits in each. Modified Videman's method was used to prepare KOA model. The acupotomy and EA group were given indicated intervention for 3 weeks. The behavior of rabbits in each group was recorded. Subsequently, cartilage-subchondral bone units were obtained and morphological changes were observed by optical microscope and micro computed tomography. Compression test was used to detect the mechanical properties of subchondral bone, Western blot and real-time polymerase chain reaction (RT-PCR) were applied to detect the expression of bone morphogenetic protein 2-Smad1 (BMP2-Smad1) pathway in subchondral bone. RESULTS: Compared with the control group, rabbits in the KOA group showed lameness, knee pain, and cartilage degradation; the subchondral bone showed active resorption, the mechanical properties decreased significantly and the BMP2-Smad1 pathway downregulated significantly. Both acupotomy and EA intervention could increase the thickness of trabecular bone (Tb. Th), the bone volume fraction (BV/TV) and the thickness of subchondral bone plate, reduce the separation of trabecular bone (Tb. Sp), improve the maximum load and elastic modulus of subchondral bone, and effectively delay cartilage degeneration in KOA rabbits. This process may be achieved through upregulation the related proteins of BMP2-Smad1 pathway. The maximum load and elastic modulus of subchondral bone in the acupotomy group were slightly better than those in the EA group. CONCLUSIONS: Acupotomy could effectively protect cartilage by inhibiting abnormal bone resorption and improving mechanical properties of subchondral bone thorough the related proteins of BMP2-Smad1 pathway in KOA rabbits.

Acupotomy inhibits aberrant formation of subchondral bone through regulating osteoprotegerin/receptor activator of nuclear factor-κB ligand pathway in rabbits with knee osteoarthritis induced by modified Videman method.

OBJECTIVE: To investigate the effects of acupotomy on inhibiting abnormal formation of subchondral bone in rabbits with knee osteoarthritis (KOA). METHODS: A total of 24 New Zealand rabbits were randomly divided into four groups of 6 rabbits each [control, model, electroacupuncture (EA) and acupotomy]. Eighteen KOA model rabbits were established using a modified Videman method. Rabbits in EA and acupotomy groups received the intervention for 3 weeks. Then, the cartilage and subchondral bone unit were obtained and the histomorphological changes were recorded. Osteo-protegerin (OPG) and receptor activator of nuclear factor-κB ligand (RANKL) in subchondral bone were evaluated by Western blotting, real-time polymerase chain reaction and immunohistochemistry. RESULTS: Compared with the model group, both the acupotomy and EA groups showed a significant decrease in the Lequesne index (both 0.01) and Mankin score ( 0.01, < 0.05). In addition, both EA and acupotomy groups had a higher expression of total articular cartilage (TAC) ( 0.05, < 0.01) and lower expression of articular calcified cartilage (ACC)/TAC ( 0.05, < 0.05) compared with the model group. The thickness of the subchondral bone plate in EA and acupotomy groups were decreased (both 0.01) compared to the model group. Moreover, trabecular bone volume (BV/TV), protein and relative expression of OPG and the ratio of OPG/RANKL in the subchondral bone of acupotomy group were decreased statistically significant, while these parameters were not significantly changed in the EA group compared with the model group. CONCLUSIONS: In the rabbit model of KOA, acupotomy inhibits aberrant formation of subchondral bone by suppressing OPG/RANKL ratio as a potential therapy for KOA.