High hydrostatic pressure induces atrial electrical remodeling through angiotensin upregulation mediating FAK/Src pathway activation

doi:10.1016/j.yjmcc.2020.01.012

Journal of Molecular and Cellular Cardiology

Volume 140, March 2020, Pages 10-21

https://doi.org/10.1016/j.yjmcc.2020.01.012 Get rights and content

Highlights

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To explore the direct effects of hydrostatic pressure on the pathogenesis of AF.
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High-pressure increased AF susceptibility by altering I_{Ca, L}, I_to, I_Kur and APD.
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Ang II-AT1R was involved in high-pressure induced atrial electrical remodeling.
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FAK-Src was the potential signaling pathway and regulated by Ang II-AT1R.

Abstract

Hypertension is an independent risk factor for atrial fibrillation (AF), although its specific mechanisms remain unclear. Previous research has been focused on cyclic stretch, ignoring the role of high hydrostatic pressure. The present study aimed to explore the effect of high hydrostatic pressure stimulation on electrical remodeling in atrial myocytes and its potential signaling pathways. Experiments were performed on left atrial appendages from patients with chronic AF or sinus rhythm, spontaneously hypertensive rats (SHRs) treated with or without valsartan (10 mg/kg/day) and HL-1 cells were exposed to high hydrostatic pressure using a self-developed device. Whole-cell patch-clamp recordings and western blots demonstrated that the amplitudes of I_Ca,L, I_to, and I_Kur were reduced in AF patients with corresponding changes in protein expression. Angiotensin protein levels increased and Ang1–7 decreased, while focal adhesion kinase (FAK) and Src kinase were enhanced in atrial tissue from AF patients and SHRs. After rapid atrial pacing, AF inducibility in SHR was significantly higher, accompanied by a decrease in I_Ca,L, upregulation of I_to and I_Kur, and a shortened action potential duration. Angiotensin upregulation and FAK/Src activation in SHR were inhibited by angiotensin type 1 receptor inhibitor valsartan, thus, preventing electrical remodeling and reducing AF susceptibility. These results were verified in HL-1 cells treated with high hydrostatic pressure, and demonstrated that electrical remodeling regulated by the FAK-Src pathway could be modulated by valsartan. The present study indicated that high hydrostatic pressure stimulation increases AF susceptibility by activating the renin-angiotensin system and FAK-Src pathway in atrial myocytes.

Graphical abstract

Introduction

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice and is associated with increased morbidity and mortality. Hypertension has been well established to be the most common medical condition associated with AF [1,2]. Epidemiological studies have shown that hypertension is an independent risk factor for AF. However, the role of hypertension, especially mechanical stress, in the pathogenesis of AF has not been fully elucidated. The cardiovascular system is subjected to three different types of mechanical stimulation: shear stress, cyclic stretch, and hydrostatic pressure [3]. Hypertension is related to increased left atrial (LA) pressure, resulting in increased pressure in individual cardiomyocytes. The main mechanical stress changes are increased cyclic stretch and hydrostatic pressure. It is involved in the pathogenesis of atrial electrical and structural remodeling and contributes to the development and persistence of AF [4,5]. While animal studies have confirmed these findings [[6], [7], [8], [9], [10]], in vitro studies on this subject are limited. Previous research has been focused on cyclic stretch, ignoring the role of high hydrostatic pressure [11,12], which is not able to mimic the pathological environment of increased atrial pressure.

The renin-angiotensin system (RAS), especially angiotensin II (Ang II)-angiotensin type 1 receptor (AT1R) pathway, plays an important role in the development of both hypertension and AF. Valsartan, an AT1R blocker for hypertension treatment, has been reported to be effective in preventing atrial electrical remodeling [13,14], but related research is limited and specific pathological mechanisms remain unclear.

Mechanical signals, such as high-pressure stimulation or mechanical stretch, can directly activate mechanically sensitive receptors and allosterically regulate integrins in cardiomyocytes; thus, activating many cytosolic protein kinases, including focal adhesion kinase (FAK) and Src. As a non-receptor protein tyrosine kinase, activated FAK can bind to Src to activate multiple signaling pathways and participate in cell proliferation and migration [15]. The FAK-mediated signaling pathway plays a role in atrial fibrogenesis and some studies have focused on the role of Src in arrhythmia [[16], [17], [18], [19], [20]]. It was hypothesized that FAK-Src is involved in atrial electrical remodeling induced by high hydrostatic pressure.

The present study aimed to explore the effect of high hydrostatic pressure stimulation on electrical remodeling in atrial myocytes and its potential signaling pathways. The results suggest a pathogenic mechanism of hypertension involved in atrial electrical remodeling and provide valuable insight into the prevention and treatment of AF.

Section snippets

Methods

Detailed methods used in this study are available in the online-only Data Supplement. Briefly, left atrial appendages (LAAs) were obtained from patients with sinus rhythm (SR) or chronic AF (no. GDREC2013047H; Guangzhou, Guangdong, China). Spontaneously hypertensive rats (SHRs) treated with or without valsartan (10 mg/kg/day) were used for the electrophysiology analysis. The current density and protein levels of ion channels were assayed using the whole-cell patch-clamp technique and western

Expression of ion channel current and protein in LAAs of patients with SR and AF

In LAAs of patients with SR and AF, ion channel current and protein expression levels were detected using the whole-cell patch clamp and western blotting, respectively. As illustrated, the amplitudes of the L-type calcium current (I_Ca,L), transient outward potassium current (I_to) and ultra-rapid delayed rectifier potassium current (I_Kur) were significantly decreased in AF compared to the SR controls (−4.74 ± 0.25 pA/pF vs. -2.73 ± 0.28 pA/pF at 10 mV, P < .01; 10.45 ± 0.92 pA/pF vs. 3.89 ± 0.97

Discussion

The present study aimed to investigate the effect of high hydrostatic pressure stimulation on electrical remodeling in atrial myocytes and its associated mechanisms. The study results demonstrated the following (Fig. 7): (1) in atrial myocytes, high-pressure stimulation shortened APD by altering the L-type calcium channel (LCC), transient outward potassium channel, and ultra-rapid delayed rectifier potassium channel, which contributed to an increase in AF susceptibility; (2) Ang II-AT1R played

Perspectives

Hypertension is recognized as a risk factor for AF, while electrical remodeling of atrial myocytes induced by high hydrostatic pressure plays an important role in the pathophysiological mechanism of AF. According to the experimental results from human specimens, hypertensive animal and cells treated with high hydrostatic pressure intervention, angiotensin induces ion channel remodeling by regulating the activation of FAK-Src and increasing AF susceptibility. The present study discovered that

Sources of funding

This work was supported by the National Natural Science Foundation of China (No. 81370295, 81670314, and 81870254), Guangzhou Municipal Science and Technology Project (201804010059), Natural Science Foundation of Guangdong Province (No. 2015A030313657), and High-level Hospital Construction Plan (No. DFJH201808).

Declaration of Competing Interest

None.

References (36)

D.H. Lau et al.
Short-term hypertension is associated with the development of atrial fibrillation substrate: a study in an ovine hypertensive model
Heart Rhythm.
(2010)
C.T. Tsai et al.
Mechanical stretch of atrial myocyte monolayer decreases sarcoplasmic reticulum calcium adenosine triphosphatase expression and increases susceptibility to repolarization alternans
J. Am. Coll. Cardiol.
(2011)
Q.Y. Zhao et al.
Acetylcholine-regulated K⁺ current remodelling in the atrium after myocardial infarction and valsartan administration
Can. J. Cardiol.
(2009)
E.G. Kleinschmidt et al.
Focal adhesion kinase signaling in unexpected places
Curr. Opin. Cell Biol.
(2017)
C.A. Rutledge et al.
C-Src kinase inhibition reduces arrhythmia inducibility and connexin43 dysregulation after myocardial infarction
J. Am. Coll. Cardiol.
(2014)
P. Zhang et al.
Focal adhesion kinase mediates atrial fibrosis via the AKT/S6K signaling pathway in chronic atrial fibrillation patients with rheumatic mitral valve disease
Int. J. Cardiol.
(2013)
F. Rao et al.
Involvement of Src in L-type Ca²⁺ channel depression induced by macrophage migration inhibitory factor in atrial myocytes
J. Mol. Cell. Cardiol.
(2009)
R. Caballero et al.
In humans, chronic atrial fibrillation decreases the transient outward current and ultrarapid component of the delayed rectifier current differentially on each atria and increases the slow component of the delayed rectifier current in both
J. Am. Coll. Cardiol.
(2010)
T. Yu et al.
Decreased expression of small-conductance Ca²⁺-activated K⁺ channels SK1 and SK2 in human chronic atrial fibrillation
Life Sci.
(2012)
J. DeSantiago et al.
Loss of p21-activated kinase 1 (Pak1) promotes atrial arrhythmic activity
Heart Rhythm.
(2018)

J. Gu et al.

Beneficial effects of pioglitazone on atrial structural and electrical remodeling in vitro cellular models

J. Mol. Cell. Cardiol.

(2013)

C.T. Tsai et al.

Angiotensin II induces complex fractionated electrogram in a cultured atrial myocyte monolayer mediated by calcium and sodium-calcium exchanger

Cell Calcium

(2011)

E. Patrucco et al.

PI3Kgamma modulates the cardiac response to chronic pressure overload by distinct kinase-dependent and -independent effects

Cell

(2004)

L. Tatton et al.

The Src-selective kinase inhibitor PP1 also inhibits kit and Bcr-Abl tyrosine kinases

J. Biol. Chem.

(2003)

A.A. Sovari et al.

Inhibition of c-Src tyrosine kinase prevents angiotensin II-mediated connexin-43 remodeling and sudden cardiac death

J. Am. Coll. Cardiol.

(2011)

M.S. Dzeshka et al.

Atrial fibrillation and hypertension

Hypertension

(2017)

F. Rahman et al.

Global epidemiology of atrial fibrillation

Nat. Rev. Cardiol.

(2014)

B.E. Sumpio et al.

Increased ambient pressure stimulates proliferation and morphologic changes in cultured endothelial cells

J. Cell. Physiol.

(1994)

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Citation Excerpt :
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¹: These authors contributed equally to this work.

View full text

High hydrostatic pressure induces atrial electrical remodeling through angiotensin upregulation mediating FAK/Src pathway activation

Highlights

Abstract

Graphical abstract

Introduction

Section snippets

Methods

Expression of ion channel current and protein in LAAs of patients with SR and AF

Discussion

Perspectives

Sources of funding

Declaration of Competing Interest

Heart Rhythm.

J. Am. Coll. Cardiol.

Can. J. Cardiol.

Curr. Opin. Cell Biol.

J. Am. Coll. Cardiol.

Int. J. Cardiol.

J. Mol. Cell. Cardiol.

J. Am. Coll. Cardiol.

Life Sci.

Heart Rhythm.

J. Mol. Cell. Cardiol.

Cell Calcium

Cell

J. Biol. Chem.

J. Am. Coll. Cardiol.

Atrial fibrillation and hypertension

Hypertension

Global epidemiology of atrial fibrillation

Nat. Rev. Cardiol.

Increased ambient pressure stimulates proliferation and morphologic changes in cultured endothelial cells

J. Cell. Physiol.