Exosomes-Shuttled lncRNA SNHG7 by Bone Marrow Mesenchymal Stem Cells Alleviates Osteoarthritis Through Targeting miR-485-5p/FSP1 Axis-Mediated Chondrocytes Ferroptosis and Inflammation
- Affiliations
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- 1Rheumatology and Immunology Department, The First Hospital of Nanchang, No. 128, North Xiangshan Road, Nanchang 330008, Jiangxi Province, China
Abstract
- BACKGROUND
Osteoarthritis (OA), a degenerative joint disorder, is a major reason of disability in adults. Accumulating evidences have proved that bone marrow mesenchymal stem cells (BMSCs)-carried exosomes play a significant therapeutic effect on OA. However, the precise regulatory network remains unknown.
METHODS
OA and normal cartilage samples were acquired from patients, and chondrocytes were exposed to IL-1b to conduct a cellular OA model. Exosomes prepared from BMSCs were identified using nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM). Cell viability was determined with CCK-8 assay. Inflammatory injury was assessed by LDH and inflammatory factors (TNF-a and IL-6) using corresponding ELISA kits, respectively. Ferroptosis was evaluated by GSH, MDA and iron levels using corresponding kits, and ROS level with DCFH-DA. The expressions of genes/proteins were determined with RT-qPCR/western bolt. RNA immunoprecipitation and luciferase activity assay were conducted for testing the interactions of small nucleolar RNA host gene 7 (SNHG7)/ferroptosis suppressor protein 1 (FSP1) and miR-485-5p.
RESULTS
The expressions of SNHG7 and FSP1 were both reduced in IL-1b-induced chondrocytes and OA cartilage tissues, and there was a positive correlation between them in clinical level. Moreover, SNHG7 was enriched in BMSCsderived exosomes (BMSCs-Exos) and could be internalized by chondrocytes. Functional analysis illustrated that BMSCsExos administration repressed inflammatory injury, oxidative stress and ferroptosis in IL-1b-induced chondrocytes, while these changes were reinforced when SNHG7 was overexpressed in BMSCs-Exos. Notably, FSP1 silencing in chondrocytes abolished the beneficial effects mediated by exosomal SNHG7.
CONCLUSIONS
Exosomal SNHG7 released from BMSCs inhibited inflammation and ferroptosis in IL-1b-induced chondrocytes through miR-485-5p/FSP1 axis. This work suggested that BMSCs-derived exosomal SNHG7 would be a prospective target for OA treatment.