Effects of miR103a3p on the autophagy and apoptosis of cardiomyocytes by regulating Atg5.
Int J Mol Med
; 43(5): 1951-1960, 2019 05.
Article
in En
| MEDLINE
| ID: mdl-30864677
ABSTRACT
Autophagy and apoptosis are associated with cardiovascular diseases. Emerging evidence shows that microRNAs (miRs) are critical in the development of pathological processes underlying cardiovascular diseases by regulating the induction of apoptosis and autophagy. The present study aimed to investigate the role of miR103a3p in cardiomyocyte injury through autophagy and apoptosis. H9c2 cells were cultured under hypoxia and reoxygenation (H/R) conditions and were used to mimic cells under ischemia. The transfection of cells with miR103a3p (mimics and inhibitors) was performed to examine its function in cardiomyocytes. The expression levels of miR103a3p were evaluated by reverse transcriptionquantitative polymerase chain reaction analysis. Cell viability was determined using an MTT assay, and the lactate dehydrogenase assay (LDH) was used to investigate cell injury. The expression levels of Bcell lymphoma 2 (Bcl2), Bcl2associated X protein, Beclin1, autophagyrelated 5 (Atg5), cleaved caspase3 and cleaved caspase9 were detected using western blotting. Immunofluorescence assays were performed to detect the expression of LC3 as a marker of autophagy. The target gene of miR103a3p was identified using dualluciferase reporter assays. The results revealed that the expression levels of miR103a3p were significantly downregulated in cardiomyocytes under H/R conditions. Injury of the cardiomyocytes was evaluated under H/R conditions. Following transfection of the cells with miR103a3p inhibitors, cell injury was increased, as determined by LDH and MTT assays. The expression levels of apoptotic proteins were consistent with the results obtained in the LDH and cell viability assays. The induction of autophagy was increased in cells under H/R conditions and cells with miR103a3p inhibitor transfection, whereas the induction of autophagy was decreased in cells transfected with miR103a3p mimics. In addition, the data indicated that miR103a3p directly targeted Atg5, which regulated the induction of autophagy and apoptosis. Taken together, these findings indicate that, following the inhibition of miR103a3p, Atg5 promotes autophagy and apoptosis in cardiomyocytes by directly targeting Atg5. Therefore, miR103a3p can be considered a potential therapeutic target for myocardial ischemia.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Autophagy
/
Apoptosis
/
Myocytes, Cardiac
/
MicroRNAs
/
Autophagy-Related Protein 5
Type of study:
Prognostic_studies
Limits:
Animals
Language:
En
Journal:
Int J Mol Med
Journal subject:
BIOLOGIA MOLECULAR
/
GENETICA MEDICA
Year:
2019
Document type:
Article