Micro-fragmented adipose tissue regulated the biological functions of osteoarthritis synoviocytes by upregulating MiR-92a-3p expression.

Apart from the treatment potential of micro-fragmented adipose tissue (MF) in joint diseases, what's less clear is the mechanism of MF on Osteoarthritis (OA). Synoviocytes isolated from synovium tissues of 11 knee joint OA patients were identified and co-cultured with MF collected by Lipogems®. Cytokines and mRNA levels in synoviocytes were detected by enzyme-linked immunosorbent assay (ELISA) and quantitative reverse transcription polymerase chain reaction (qRT-PCR). Cell viability, apoptosis and apoptosis-related protein expression of Tumor Necrosis Factor-α (TNF-α)-activated synoviocytes were detected by cell counting kit-8, flow cytometry and western blot, respectively. The rescue experiments were conducted to verify the causal relationship of MF and miR-92a-3p. The relationship between miR-92a-3p and KLHL29 was verified by bioinformatics analysis, qRT-PCR, dual-luciferase reporter assay and western blot. OA synoviocytes were composed of synovial fibroblasts and synovial macrophages. After co-cultivation of synoviocytes and TNF-α, the levels of Interleukin (IL)-8 and hyaluronic acid (HA) appeared a few changes, and those of chemotactic cytokine ligand (CCL) 2, CCL3, CCL5 and matrix metalloproteinases (MMP)-9 were downregulated, while the levels of Tissue Inhibitor of Metalloproteinases (TIMP)-1, IL-10 and Prostaglandin E2 (PGE) were up-regulated. Co-culture of MF and activated synoviocytes reversed the above-mentioned effects regulated by TNF-α and reduced the mRNA levels of inflammatory factors. However, miR-92a-3p inhibitor overturned the reversal. KLHL29 was the target gene of miR-92a-3p and its expression was suppressed in activated synoviocytes co-cultured with MF, which was reversed by down-regulated miR-92a-3p. Collectively, MF regulated the biological functions of OA synoviocytes by upregulating miR-92a-3p expression.