[HTML][HTML] MicroRNA-155 suppresses autophagy in chondrocytes by modulating expression of autophagy proteins
S D'Adamo, O Alvarez-Garcia, Y Muramatsu… - Osteoarthritis and …, 2016 - Elsevier
Osteoarthritis and Cartilage, 2016•Elsevier
Objective Autophagy dysfunction has been reported in osteoarthritis (OA) cartilage. The
objective of this study was to investigate the role of microRNA-155 (miR-155), which is
overexpressed in OA, in the regulation of autophagy in human chondrocytes. Design
Rapamycin (50 nM) and 2-deoxyglucose (2-DG)(5 mM) were used to stimulate autophagy in
primary human articular chondrocytes and in the T/C28a2 human chondrocyte cell line.
Cells were transfected with LNA GapmeR or mimic specific for miR-155 and autophagy flux …
objective of this study was to investigate the role of microRNA-155 (miR-155), which is
overexpressed in OA, in the regulation of autophagy in human chondrocytes. Design
Rapamycin (50 nM) and 2-deoxyglucose (2-DG)(5 mM) were used to stimulate autophagy in
primary human articular chondrocytes and in the T/C28a2 human chondrocyte cell line.
Cells were transfected with LNA GapmeR or mimic specific for miR-155 and autophagy flux …
Objective
Autophagy dysfunction has been reported in osteoarthritis (OA) cartilage. The objective of this study was to investigate the role of microRNA-155 (miR-155), which is overexpressed in OA, in the regulation of autophagy in human chondrocytes.
Design
Rapamycin (50 nM) and 2-deoxyglucose (2-DG) (5 mM) were used to stimulate autophagy in primary human articular chondrocytes and in the T/C28a2 human chondrocyte cell line. Cells were transfected with LNA GapmeR or mimic specific for miR-155 and autophagy flux was assessed by LC3 western blotting and by Cyto-ID® dye quantification in autophagic vacuoles. Expression of predicted miR-155 targets in the autophagy pathway were analyzed by real-time PCR and western blotting.
Results
Autophagy flux induced by rapamycin and 2-DG was significantly increased by miR-155 LNA, and significantly decreased after miR-155 mimic transfection in T/C28a2 cells and in human primary chondrocytes. These effects of miR-155 on autophagy were related to suppression of gene and protein expression of key autophagy regulators including Ulk1, FoxO3, Atg14, Atg5, Atg3, Gabarapl1, and Map1lc3.
Conclusion
MiR-155 is an inhibitor of autophagy in chondrocytes and contributes to the autophagy defects in OA.
Elsevier