Core Viewpoint - The research team at Tianjin University has developed a novel streamlined zinc oxide composite injectable hydrogel that opens new pathways for the treatment of osteoarthritis and cartilage regeneration [1][2] Group 1: Hydrogel Characteristics - The hydrogel exhibits dual characteristics of being "smooth during injection" and "firm after implantation" [1] - The streamlined zinc oxide structure optimizes the rheological and mechanical properties of the hydrogel, providing high mechanical strength and low flow viscosity [1][2] Group 2: Mechanism and Functionality - The hydrogel addresses the critical issue of extracellular matrix homeostasis imbalance in osteoarthritis treatment by incorporating matrix metalloproteinase-responsive features and delivering the miR-17-5p gene drug [1] - miR-17-5p is a small RNA molecule that effectively inhibits the overactive matrix metalloproteinases responsible for excessive degradation of the extracellular matrix [1] Group 3: Injection and Performance - The internal streamlined zinc oxide nanoparticles reduce fluid resistance during injection, allowing for smoother passage through the injection needle and rapid filling of irregular tissue defects [2] - Upon injection, the hydrogel undergoes a cross-linking reaction, forming a stronger network structure that enhances its mechanical performance and resistance to external mechanical stress [2] Group 4: Gene Therapy Implications - The streamlined structure significantly improves the transfection efficiency of miR-17-5p, providing new insights for precise delivery in gene therapy [2] - This design not only reduces energy loss during the injection process but also greatly enhances the hydrogel's supporting capacity at tissue defect sites, ensuring long-term treatment efficacy and structural integrity [2]