Polyunsaturated fatty acids suppress PIEZO ion channel mechanotransduction in articular chondrocytes.

Osteoarthritis (OA) is characterized by articular cartilage degeneration, leading to pain and loss of joint function. Recent studies have demonstrated that omega-3 (ω3) polyunsaturated fatty acid (PUFA) supplementation can decrease injury-induced OA progression in mice fed a high-fat diet. Furthermore, PUFAs have been shown to influence the mechanical properties of chondrocyte membranes, suggesting that alterations in mechanosensitive ion channel signaling could contribute to the mechanism by which ω3 PUFAs decreased OA pathogenesis.

PIEZO1-mediated calcium influx transiently alters nuclear mechanical properties via actin remodeling in chondrocytes.

Mechanosensation allows cells to generate intracellular signals in response to mechanical cues from their environment. Previous research has demonstrated that mechanical stress can alter the mechanical properties of the nucleus, affecting gene transcription, chromatin methylation, and nuclear mechanoprotection during mechanical loading. PIEZO1, a mechanically gated Ca ion channel, has been shown to be important in sensing mechanical stress, however its signal transduction pathway is not thoroughly understood.

Mode of injury and level of synovitis alter inflammatory chondrocyte gene expression and associated pathways.

Although various joint injuries result in post-traumatic osteoarthritis (PTOA), differences in chondrocyte response to specific injuries, such as blunt compression or fracture, are unclear. Furthermore, the role of underlying joint inflammation, or synovitis, is often not considered. We investigated how injury mechanisms and underlying synovitis affect chondrocyte gene expression using osteochondral injury models with synovial co-culture.

Engineered self-regulating macrophages for targeted anti-inflammatory drug delivery.

Background: Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by increased levels of inflammation that primarily manifests in the joints. Macrophages act as key drivers for the progression of RA, contributing to the perpetuation of chronic inflammation and dysregulation of pro-inflammatory cytokines such as interleukin 1 (IL-1). The goal of this study was to develop a macrophage-based cell therapy for biologic drug delivery in an autoregulated manner.