[Effect of needle-knife on chondrocyte apoptosis of knee joint in rabbits with knee osteoarthritis based on CircSERPINE2-miR-1271-5P-ERG axis].

Objective: To observe the effect of needle-knife on the chondrocyte apoptosis of knee joint in rabbits with knee osteoarthritis (KOA) based on the CircSERPINE2-miR-1271-5P-E26 specific transformation-related gene (ERG) axis, and to explore the mechanism of needle-knife for KOA.

Methods: Thirty-six New Zealand white rabbits were randomly divided into a normal group, a model group, a needle-knife group and a sham needle-knife group, 9 rabbits in each group. The rabbits in the model group, the needle-knife group and the sham needle-knife group were treated with modified Videman method to prepare KOA model. After successful modeling, the rabbits in the needle-knife group were treated with needle-knife at cord adhesion and nodules near quadriceps femoris tendon and internal and external collateral ligament on the affected knee joint; the rabbits in the sham needle-knife group were treated with sham needle-knife baside the needle insertion point of the needle-knife group (needle-knife was only inserted, without any operation). The treatment was given once a week, 3 times in total. The Lequesne MG behavioral score was used to evaluate the knee joint damage in each group before and after intervention. After intervention, HE staining and transmission electron microscopy were used to observe the cartilage tissue morphology and ultrastructure of chondrocytes in the knee joint in each group; TUNEL method was used to detect the level of chondrocyte apoptosis in the knee joint; real-time fluorescence quantitative PCR was used to detect the expression of CircSERPINE2, miR-1271-5P and ERG mRNA in knee cartilage tissue in each group.

Results: After intervention, compared with the normal group, the Lequesne MG behavioral score in the model group was increased (<0.01). Compared with the model group and the sham needle-knife group, the Lequesne MG behavioral score in the needle-knife group was decreased (<0.01). In the model group and the sham needle-knife group, the number of chondrocytes and organelles was decreased, the cell nucleus was shrunk, mitochondria was swelling or disappeared; in the needle-knife group, the number of chondrocytes and organelles was increased, the cell nucleus was not obviously shrunk and the mitochondria was not obviously swelling. Compared with the normal group, the level of chondrocyte apoptosis in the model group was increased (<0.01); compared with the model group and the sham needle-knife group, the level of chondrocyte apoptosis in the needle-knife group was decreased (<0.01, <0.05). Compared with the normal group, the expression of CircSERPINE2 and ERG mRNA in the model group was decreased (<0.01), and the expression of miR-1271-5P mRNA was increased (<0.01); compared with the model group and the sham needle-knife group, the expression of CircSERPINE2 and ERG mRNA in the needle-knife group was increased (<0.01), and the expression of miR-1271-5P mRNA was decreased (<0.01).

Conclusion: Needle-knife could reduce the knee joint damage and chondrocyte apoptosis in KOA rabbits, which may be related to up-regulating the expression of CircSERPINE2 and ERG mRNA, and inhibiting the expression of miR-1271-5P mRNA.