Silencing microRNA-34a inhibits chondrocyte apoptosis in a rat osteoarthritis model in vitro.
OBJECTIVE
miRNAs, which are non-coding RNAs, play a role in the pathogenesis of disease including OA. miRNA (miR)-34a is induced by p53, subsequently leading to cell apoptosis, which is one of the major factors in the pathogenesis of OA. The purpose of this study is to investigate the effect of silencing miR-34a on IL-1β-induced chondrocyte apoptosis in a rat OA model in vitro.


METHODS
Locked nucleotide analogue (LNA)-modified miR-34a-specific anti-sense was transfected into rat chondrocyte monolayer culture. After that, IL-1β was added to the chondrocytes to create an OA model in vitro. The effect of silencing miR-34a on the prevention of chondrocyte apoptosis was analysed by assessment of the expression levels of Col2a1 and iNOS, also through assessment of cell viability and TUNEL staining.


RESULTS
The expression of miR-34a was significantly up-regulated by IL-1β. Silencing of miR-34a significantly prevented IL-1β-induced down-regulation of Col2a1, as well as IL-1β-induced up-regulation of iNOS. Finally, MiR-34a inhibitor could also reduce TUNEL-positive cells.


CONCLUSIONS
Silencing of miR-34a by LNA-modified anti-sense could effectively reduce rat chondrocyte apoptosis induced by IL-1β. This present study revealed that silencing of miR-34a might develop a novel intervention for OA treatment through the prevention of cartilage degradation.
Abouheif
Mohamed M
MM
Department of Orthopaedic Surgery, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
Nakasa
Tomoyuki
T
Shibuya
Hayatoshi
H
Niimoto
Takuya
T
Kongcharoensombat
Wirat
W
Ochi
Mitsuo
M
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D001169:Arthritis, Experimental / Q000378:metabolism* / Q000473:pathology; D002478:Cells, Cultured; D019902:Chondrocytes / Q000187:drug effects* / Q000378:metabolism; D015536:Down-Regulation / Q000187:drug effects; D035683:MicroRNAs / Q000235:genetics*; D023421:Models, Animal; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction
C522425:MIRN34 microRNA, human; D035683:MicroRNAs