Simulated microgravity recapitulates early molecular events and sex differences of knee osteoarthritis

This study aims to establish an osteoarthritis (OA)-like phenotype in human meniscus models under SMG conditions and assess whether sex-dependent expression patterns indicative of knee OA (KOA) are present under short-term SMG. Cell cultures were maintained on human matrix coated surface to maintain original phenotype. Overall design: Primary fibrochondrocytes obtained from six donors (three male and three female) without KOA were cultured on human matrix coated surface and used to engineer human meniscus constructs. The constructs were cultured under normal gravity and simulated microgravity for seven days, and samples were collected on days 0, 1, 3, and 7. The expression levels of selected markers and whole transcriptome profile were assessed using RT-qPCR and RNA sequencing.