Mechanism underlying exosomal lncRNA H19 derived from umbilical cord mesenchymal stem cells promotes cartilage injury repair
- VernacularTitle:脐带间充质干细胞外泌体LncRNA H19修复软骨损伤的机制
- Author:
Xianfeng WANG
1
;
Kun WANG
;
Han SUN
;
Xiaoliang SUN
;
Litao YAN
Author Information
- Keywords: osteoarthritis; mesenchymal stem cell; exosome; long non-coding RNA
- From: Chinese Journal of Tissue Engineering Research 2024;28(1):20-25
- CountryChina
- Language:Chinese
- Abstract: BACKGROUND:Umbilical cord mesenchymal stem cells(UMSCs)have been proven to have therapeutic effects on cartilage injury,and exosomes are the main carriers for UMSCs to exert therapeutic effects in vivo.Our research group previously found that lncRNA H19 is an important active molecule that mediates the activity of UMSCs-derived exosomes regulating chondrocytes.LncRNA H19 could adsorb miR-29b-3p to promote the proliferation and regeneration of chondrocytes,but its downstream mechanism is still unclear. OBJECTIVE:To reveal the specific mechanism of UMSCs in the treatment of cartilage injury from the perspective of exosomes and lncRNAs,so as to provide a new target for the treatment of cartilage injury. METHODS:UMSCs stably overexpressing lncRNA H19 were constructed.H19-Exos were extracted by ultra-centrifugation.The exosomes were identified by transmission electron microscopy,Nanosight,western blot assay and exosome uptake assay.The effect of miR-29b-3p overexpression and silencing on the TGF-β1/Smad3 pathway was detected by western blot assay,qPCR and dual luciferase reporter gene system.The biological effect of H19-Exos on cartilage regeneration was verified by the specific TGF-β1/Smad3 inhibitor in vitro and in vivo. RESULTS AND CONCLUSION:(1)H19-Exos showed a typical cup shape under an electron microscope,and the particle size was approximately 130 nm.H19-Exos expressed CD63,CD81 and TSG1010.(2)Overexpression of miR-29b-3p could down-regulate the mRNA and protein levels of TGF-β1 and Smad3,while silencing miR-29b-3p could up-regulate the mRNA and protein levels of TGF-β1/Smad3.(3)Dual-luciferase reporter gene system showed that miR-29b-3p had significant differences in the activities of downstream target genes TGF-β1 and Smad3.(4)The osteoarthritis models of rats were successfully established by injection of type II collagenase into the knee joint.H19-Exos significantly promoted cartilage regeneration.The specific TGF-β1/Smad3 inhibitor SB-431542 could block the biological effect of H19-Exos on cartilage regeneration in vitro and in vivo.(5)This study systematically demonstrated the promotion effect of UMSCs-derived exosomes highly expressing lncRNA H19 on cartilage regeneration,and the specific mechanism is that lncRNA H19 promotes cartilage regeneration by targeting miR-29b-3p/TGF-β1/Smad3 pathway.
