Regulatory effect of transcription factor E4BP4 on pathological myocardial fibrosis through the AMPK-TGF-β1/SMAD3 signaling pathway
10.13406/j.cnki.cyxb.003762
- VernacularTitle:转录因子E4BP4通过AMPK-TGF-β1/SMAD3信号转导途径调控病理性心肌纤维化
- Author:
Derong HUANG
1
;
Qing WEN
;
Yuchen SU
Author Information
1. 遵义医科大学附属医院心脏大血管外科,遵义 563000
- Keywords:
myocardial fibrosis;
adenovirus E4 promoter-binding protein;
adenosine monophosphate-activated protein kinase;
trans-forming growth factor-β;
Smad homolog 3
- From:
Journal of Chongqing Medical University
2025;50(5):640-648
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the effects of transcription factor adenovirus E4 promoter-binding protein(E4BP4)in regulating pathological myocardial fibrosis through the adenosine monophosphate-activated protein kinase(AMPK)-transforming growth factor(TGF)-β1/Smad homolog 3(SMAD3)pathway.Methods:A mouse model of myocardial fibrosis was established,and the expression of E4BP4 was determined in the model group and the sham-operation group.Primary cardiac fibroblasts were isolated,cultured,activated by angiotensin Ⅱ(Ang Ⅱ),and divided into the following groups:Ang Ⅱ+E4BP4 group(transfected with E4BP4 overexpression plasmids),Ang Ⅱ+siE4BP4 group(transfected with E4BP4 interfering plasmids),Ang Ⅱ group,and control group(without Ang Ⅱtreatment).The fluorescence intensity of ɑ-smooth muscle actin(α-SMA)was determined by the immunofluorescence assay,the cell viability by the cell counting kit,the expression of E4BP4,α-SMA,collagen type Ⅰ(collagen Ⅰ),and collagen type Ⅲ(collagen Ⅲ)by polymerase chain reaction,and the protein expression of TGF-β1,AMPK,and SMAD3 by Western blot.Results:Compared with the sham-operation group,the model group showed significantly in-creased myocardial fibrosis degree(38.46±1.21 vs.3.39±0.39,t=-78.564,P=0.000)and E4BP4 protein expression(0.96±0.03 vs.0.75±0.03,t=-11.480,P=0.000).In vitro experiments found that the mean fluorescence intensity(0.05±0.01 vs.0.42±0.03,F=677.591,P=0.000),cell viability(91.30±2.39 vs.123.74±2.60,F=132.696,P=0.000),and the levels of α-SMA(1.26±0.09 vs.3.59±0.86,F=52.274,P=0.000),collagen Ⅰ(1.16±0.11 vs.3.79±0.89,F=55.336,P=0.000),collagen Ⅲ(1.23±0.13 vs.2.92±0.36,F=119.929,P=0.000),TGF-β1(0.66±0.04 vs.0.96±0.02,F=142.954,P=0.000),and p-SMAD3/SMAD3(0.81±0.03 vs.1.37±0.02,F=739.609,P=0.000)in the Ang Ⅱ+siE4BP4 group were significantly lower than those in the Ang Ⅱ+E4BP4 group.The expression of p-AMPK/AMPK in the Ang Ⅱ+siE4BP4 group was significantly higher than that in the Ang Ⅱ+E4BP4 group(0.89±0.01 vs.0.58±0.02,F=284.541,P=0.000).Conclusion:E4BP4 plays a crucial role in the regulation of fibrosis.Inhibition of E4BP4 expression exerts an anti-fibrotic effect by activating AMPK and inhibiting TGF-β1/SMAD3 pathway.
