Exploring New Horizons: Advancements in Cartilage Tissue Engineering Under Space Microgravity.

Novel investigations of how microgravity affects cellular and tissue development have recently been made possible by the multidisciplinary fusion of tissue engineering and space science. This review examines the intersection of cartilage tissue engineering (CTE) and space science, focusing on how microgravity affects cartilage development. Space microgravity induces distinct physiological changes in chondrocytes, including a 20-30% increase in cell diameter, a 1.5- to 2-fold increase in proliferation rates, and up to 3-fold increases in chondrogenic markers such as SOX9 and collagen type II. These cellular alterations impact extracellular matrix composition and tissue structure. Space-optimized bioreactors using dynamic culture methods replicate physiological conditions and enhance tissue growth, but the absence of gravity raises concerns about the mechanical properties of engineered cartilage. Key research areas include the role of growth factors in cartilage development under microgravity, biocompatibility and degradation of scaffold materials in space, and in situ experiments on space stations. This review highlights the opportunities and challenges in leveraging microgravity for CTE advancements, emphasizing the need for continued research to harness space environments for therapeutic applications in cartilage regeneration. The multidisciplinary fusion of tissue engineering and space science opens novel avenues for understanding and improving cartilage tissue engineering, with significant implications for the future of biomedical applications in space and on Earth.