MicroRNA‑489 suppresses isoproterenol‑induced cardiac fibrosis by downregulating histone deacetylase 2

Figures

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  Figure 1.. Pathological changes in myocardial tissue and expression of fibrosis-associated markers in ISO-treated rat heart tissues and CFs. (A) H&E and Masson staining revealed myocardial collagen deposition in myocardial tissues subsequent to ISO injection (scale bar, 100 µm). (B) CK activity, (C) CK-MB activity and (D) cTnI concentration were measured in the serum of ISO-treated and normal control rats. (E) miR-489 expression, and (F) Col1A1 and α-SMA mRNA levels in heart tissues obtained from the control and ISO-treated rats, as well as (G) miR-489, and (H) Col1A1 and α-SMA levels in the control and ISO-treated CFs were determined by reverse transcription-quantitative polymerase chain reaction. The data are presented as the mean ± standard deviation. *P<0.05 vs. saline group. ISO, isoproterenol; CFs, cardiac fibroblasts; CK, creatine kinase; CK-MB, CK isozyme; cTnI, troponin I; miR, microRNA; Col1A1, collagen I; α-SMA, α-smooth muscle actin.

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  Figure 2.. miR-489 overexpression inhibited the viability and differentiation of CFs. (A) miR-489 expression, and (B) Col1A1 and α-SMA mRNA levels in CFs transfected with NC and miR-489 mimic were determined by reverse transcription-quantitative polymerase chain reaction. *P<0.05 vs. NC group. (C) An MTT assay was used to investigate the viability of CFs transfected with NC and miR-489 mimic treated with ISO. The data are presented as the mean ± standard deviation. *P<0.05 and **P<0.01. miR, microRNA; CFs, cardiac fibroblasts; NC, negative control; Col1A1, collagen I; α-SMA, α-smooth muscle actin.

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  Figure 3.. miR-489 directly targets HDAC2. (A) Bioinformatics analysis suggested that the 3′-untranslated region of HDAC2 was complementary to miR-489. (B) The luciferase reporter assay revealed that miR-489 binds to WT HDAC2, but not MUT HDAC2 in 293T cells. (C) RT-qPCR was used to determine the expression levels of miR-489 and HDAC2 mRNA in isoproterenol-treated CFs transfected with NC, miR-489 mimic or miR-489 inhibitor. (D) HDAC2 expression, and (E) Col1A1 and α-SMA mRNA levels in CFs transfected with siNC and siHDAC2 were determined by RT-qPCR. The data are presented as the mean ± standard deviation. *P<0.05 and **P<0.01, vs. corresponding NC group. miR, microRNA; HDAC2, histone deacetylase 2; WT, wild-type; MUT, mutant; RT-qPCR, reverse transcription-quantitative polymerase chain reaction; CFs, cardiac fibroblasts; NC, negative control; Col1A1, collagen I; α-SMA, α-smooth muscle actin; si, small interfering RNA.

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  Figure 4.. miR-489 inhibited the isoproterenol-induced cardiac fibrosis induced via HDAC2. (A) RT-qPCR was used to determine the expression level of HDAC2 in CFs transfected with pcDNA3.1 and pcDNA3.1-HDAC2. (B) HDAC2, and (C) Col1A1 and α-SMA expression levels in CFs transfected with NC, miR-489 mimic or miR-489 mimic plus HDAC2 were determined by RT-qPCR. (D) An MTT assay was used to assess the viability of CFs transfected with NC, miR-489 mimic or miR-489 mimic plus HDAC2. The data are presented as the mean ± standard deviation. *P<0.05 and **P<0.01. miR, microRNA; HDAC2, histone deacetylase 2; RT-qPCR, reverse transcription-quantitative polymerase chain reaction; CFs, cardiac fibroblasts; Col1A1, collagen I; α-SMA, α-smooth muscle actin; NC negative control.