Regulatory effect of 3'-tRF-PheGAA on Ang Ⅱ-induced cardiomyocyte hypertrophy and its mechanism

Abstract

Objective To investigate the regulatory effect of 3'-tRF-PheGAA on angiotensin Ⅱ (Ang Ⅱ)-induced cardiomyocyte hypertrophy and its mechanism. Methods Primary cardiomyocytes of neonatal mice were obtained and cultured for 24 h, and were then divided into groups A to G. The cardiomyocytes in group A were cultured with DMEM/F12 complete culture medium for 36 h. The cardiomyocytes in group B were transfected with negative control (NC) for 36 h. The cardiomyocytes in group C were transfected with agomir-3'-tRF-PheGAA for 36 h. The cardiomyocytes in group D were cultured with DMEM/F12 complete culture medium for 84 h. The cardiomyocytes in group E were treated with Ang Ⅱ at a final concentration of 1 μmol/L for 48 h. The cardiomyocytes in group F were transfected with anta-NC for 36 h and then treated with Ang Ⅱ at a final concentration of 1 μmol/L for 48 h. The cardiomyocytes in group G were transfected with anta-3'-tRF-PheGAA for 36 h and then treated with Ang Ⅱ at a final concentration of 1 μmol/L for 48 h. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to determine the gene expression levels of 3'-tRF-PheGAA, atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and β-myosin heavy chain (β-MHC) in the cardiomyocytes in each group. Rhodamine-labeled phalloidin was used to stain F-actin in the cardiomyocytes in each group and calculate the skeletal surface area of cardiomyocytes. Results The RT-qPCR results showed significant differences between groups A to C in the gene expression levels of 3'-tRF-PheGAA, ANP, BNP, and β-MHC in cardiomyocytes (F=137.10-1 061.00,P<0.05). The gene expression levels of 3'-tRF-PheGAA, ANP, BNP, and β-MHC were significantly upregulated in group C compared to group A (P<0.05). There were significant differences between groups D to G in gene expression levels of 3'-tRF-PheGAA, ANP, BNP, and β-MHC in cardiomyocytes (F=117.60-572.30,P<0.05). The gene expression levels of 3'-tRF-PheGAA, ANP, BNP, and β-MHC were significantly decreased in group G compared to group E (P<0.05). The staining results of rhodamine-labeled phalloidin showed significant differences between groups A to C in the skeletal surface area of cardiomyocytes (F=35.06,P<0.05). The skeletal surface area was significantly increased in group C compared to group A (P<0.05). There were significant differences between groups D to G in skeletal surface area of cardiomyocytes (F=48.05,P<0.05); the skeletal surface area was significantly reduced in group G compared to group E (P<0.05). Conclusion 3'-tRF-PheGAA inhibit its expression to alleviate Ang Ⅱ-induced cardiomyocyte hypertrophy by inhibiting 3'-tRF-PheGAA expression.

Keywords

• rna, small untranslated|angiotensinⅱ|myocytes, cardiac|cardiomegaly