Lentivirus-based shRNA of Caspase-3 gene silencing inhibits chondrocyte apoptosis and delays the progression of surgically induced osteoarthritis

Chondrocyte apoptosis is an important pathological feature of osteoarthritis (OA). Excessive apoptosis of chondrocytes disrupts the dynamic balance of cell proliferation and apoptosis, with a marked reduction in chondrocytes and cartilage matrix disintegration, which represents the main pathology of OA. Caspases, especially Caspase-3, play a central role in cell apoptosis. In this study, a lentiviral vector was used to transduce caspase-3 short hairpin RNA (shRNA) into rat chondrocytes (RCs), and the apoptotic and phenotypic genes of RCs were analyzed using real-time PCR and western blotting in vitro. In addition, in vivo intra-articular injection of Caspase-3 shRNA lentivirus was performed in a surgically induced OA rat model. Our results showed that Caspase-3 gene silencing could down-regulate the TNF-alpha-mediated inflammatory gene expression of TNFR1, FADD, and IL-1 beta, apoptotic gene expression of APAF1, Caspase-3, and Caspase-9, thereby attenuating the apoptotic pathway in vitro. Caspase-3 gene silencing also attenuated TNF-alpha-mediated decreased gene expression of ACAN, Col1-a1, and Col2-a1. Furthermore, Caspase-3 gene silencing could effectively reduce the OARSI score, and gene expression of Caspase-3, Caspase-9, MMP13, and TNF-alpha in a surgically induced OA rat model. Caspase-3 gene silencing may serve as a novel therapeutic strategy for cartilage injury and OA. Apoptosis of chondrocytes is an important pathological feature of osteoarthritis (OA). This study demonstrated that using a lentivirus-based gene delivery system to silence gene Caspase-3 could protect cells from TNF-alpha-mediated apoptosis, limit the extent of cartilage lesions, and promote repair of the surgically induced OA by maintaining cellular phenotypic properties. The research scheme for delivery of therapeutic gene by intra-articular injection can provide direct and effective experimental evidence for clinical translational application and open up a new way for the treatment of OA. image