Knockdown of exosome‑mediated lnc‑PVT1 alleviates lipopolysaccharide‑induced osteoarthritis progression by mediating the HMGB1/TLR4/NF‑κB pathway via miR‑93‑5p.

Abstract

Osteoarthritis is a chronic degenerative joint disease. Long non-coding RNA plasmacytoma variant translocation 1 (PVT1) is involved in the progression of osteoarthritis and exosomes serve a central role in intercellular communication. However, whether PVT1 can be mediated by exosomes in osteoarthritis has not been reported. Whole blood was drawn from osteoarthritis patients and healthy volunteers. Lipopolysaccharide (LPS) was used to stimulate human normal chondrocytes (C28/I2) to construct a cell damage model in vitro. Protein levels were examined via western blot analysis. eThe expression of PVT1, microRNA (miR)-93-5p and high mobility groupprotein B1 (HMGB1) was evaluated through reverse transcription-quantitative PCR. Cell viability and apoptosis were determined through CCK-8 or flow cytometric assay. Inflammatory cytokines were measured via ELISA. The relationship between PVT1 or HMGB1 and miR-93-5p was confirmed by dual-luciferase reporter assay. PVT1, HMGB1 and exosomal PVT1 were upregulated while miR-93-5p was downregulated in osteoarthritis patient serum and LPS-induced C28/I2 cells. Exosomes from osteoarthritis patient serum and LPS-treated C28/I2 cells increased PVT1 expression in C28/I2 cells. PVT1 depletion reversed the decrease of viability and the increase of apoptosis, inflammation responses and collagen degradation of C28/I2 cells induced by LPS. PVT1 regulated HMGB1 expression via sponging miR-93-5p. miR-93-5p inhibition abolished PVT1 silencing-mediated viability, apoptosis, inflammation responses and collagen degradation of LPS-stimulated C28/I2 cells. HMGB1 increase overturned miR-93-5p upregulation-mediated viability, apoptosis, inflammation responses and collagen degradation of LPS-stimulated C28/I2 cells. Furthermore, PVT1 modulated the Toll-like receptor 4/NF-κB pathway through an miR-93-5p/HMGB1 axis. In summary, exosome-mediated PVT1 regulated LPS-induced osteoarthritis progression by modulating the HMGB1/TLR4/NF-κB pathway via miR-93-5p, providing a new route for possible osteoarthritis treatment.