Investigating Sex-Linked miRNAs for Potential Osteoarthritis Therapy Biomarkers.

Sex-specific factors can influence the onset and progression of osteoarthritis (OA), yet the molecular mechanisms underlying their impact remain poorly defined. This study investigated whether plasma microRNAs (miRNAs) correlate to sex-dependent OA progression, based on evidence of enhanced spontaneous osteoclastogenesis in peripheral blood mononuclear cells (PBMCs) derived from OA patients. miRNAs were evaluated on OA-plasma (n = 20 men, 20 women with knee OA; KL grade I-II) and their role on OA signaling was investigated through bioinformatic analysis. Seven miRNAs were identified as significantly upregulated in men' vs. women' samples: hsa-miR-107, hsa-miR-23a-3p, hsa-miR-103a-3p, hsa-let-7g-5p, hsa-miR-22-3p, hsa-miR-106a-5p, hsa-miR-142-3p, and were associated with OA-related tissues and pathways. Notably, two common targets were identified: Adenosine Triphosphate Citrate Lyase (ACLY), a key enzyme linking citrate metabolism to epigenetic regulation, and phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1), a component of the phosphatidylinositol-3-kinase PI3K/AKT/mTOR pathway. In men, increased miRNA expression may repress ACLY and PIK3R1, affecting catabolic gene expression, inflammation, and OA progression. Conversely, their lower expression in women may mitigate these effects by counterbalancing the OA-promoting influences driven by sex hormones. A functional validation is needed to confirm miRNA-ACLY/PIK3R1 interactions and their sex-specific roles in early OA pathophysiology.