Loss of AMIGO2 causes dramatic damage to cardiac preservation after ischemic injury
Abstract
Background: Recent studies have identified amphoterin-induced gene and open reading frame (AMIGO2). The role of AMIGO2 in tumour research is well-studied, but its role in ischemic heart diseases is seldom reported. In the present study, the role of AMIGO2 in myocardial infarction (MI) is under investigation for the first time.
Methods: For in vitro studies, cardiomyocytes (CMs) and endothelial cells (ECs) were isolated from both AMIGO2 knockout (KO) and WT mice. The apoptosis of CMs was tested after 48 h of ischemic stimulation. A proliferation test was implemented after 7 days of normoxic incubation and tube formation on ECs. For in vivo studies, the MI model was built in mice hearts. Echocardiographic evaluation was performed at 3 days and 28 days post-MI, while the hemodynamics test was performed at 28 days post-MI. The histological results of the apoptosis, proliferation, angiogenesis and infarct zone assessments were determined using terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) assay, Ki67 staining, a-SMA/CD31 immunostain and the Masson-Trichrome method, respectively. The expression changes of the Akt pathway and related proteins were confirmed using both quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot.
Results: The present results demonstrated that AMIGO2 deficiency caused more CMs suffering apoptosis, lower proliferation and less angiogenesis in vitro and in vivo. Weaker cardiac function and larger scar formation were detected in AMIGO2 KO mice, and increased expression of active-caspase-3 and decreased expression of PDK1, p-Akt, Bcl-2/Bax and VEGF occurred.
Conclusions: Herein the findings indicate that AMIGO2 deficiency plays an attenuated cardio-protective role in ischemic heart disease via inactivation of the PDK1/Pten/Akt pathway.
Keywords: AMIGO2myocardial infarctionapoptosisangiogenesis
References
- Alpert JS, Thygesen K, Antman E, et al. Myocardial infarction redefined--a consensus document of The Joint European Society of Cardiology/American College of Cardiology Committee for the redefinition of myocardial infarction. J Am Coll Cardiol. 2000; 36(3): 959–69.
- Kitsis RN, Peng CF, Cuervo AM. Eat your heart out. Nat Med. 2007; 13(5): 539–541.
- White HD, Norris RM, Brown MA, et al. Left ventricular end-systolic volume as the major determinant of survival after recovery from myocardial infarction. Circulation. 1987; 76(1): 44–51.
- Pluta A, Stróżecki P, Krintus M, et al. Left ventricular remodeling and arterial remodeling in patients with chronic kidney disease stage 1-3. Ren Fail. 2015; 37(7): 1105–1110.
- Kuja-Panula J, Kiiltomäki M, Yamashiro T, et al. AMIGO, a transmembrane protein implicated in axon tract development, defines a novel protein family with leucine-rich repeats. J Cell Biol. 2003; 160(6): 963–973.
- Kajander T, Kuja-Panula J, Rauvala H, et al. Crystal structure and role of glycans and dimerization in folding of neuronal leucine-rich repeat protein AMIGO-1. J Mol Biol. 2011; 413(5): 1001–1015.
- Rabenau KE, O'Toole JM, Bassi R, et al. DEGA/AMIGO-2, a leucine-rich repeat family member, differentially expressed in human gastric adenocarcinoma: effects on ploidy, chromosomal stability, cell adhesion/migration and tumorigenicity. Oncogene. 2004; 23(29): 5056–5067.
- Andersson U, Harris HE. The role of HMGB1 in the pathogenesis of rheumatic disease. Biochim Biophys Acta. 2010; 1799(1-2): 141–148.
- Thompson CB. Apoptosis in the pathogenesis and treatment of disease. Science. 1995; 267(5203): 1456–1462.
- Dimmeler S, Zeiher AM. Endothelial cell apoptosis in angiogenesis and vessel regression. Circ Res. 2000; 87(6): 434–439.
- Sheppard K, Kinross KM, Solomon B, et al. Targeting PI3 kinase/AKT/mTOR signaling in cancer. Crit Rev Oncog. 2012; 17(1): 69–95.
- Raimondi C, Falasca M. Targeting PDK1 in cancer. Curr Med Chem. 2011; 18(18): 2763–2769.
- Maehama T, Taylor GS, Dixon JE. PTEN and myotubularin: novel phosphoinositide phosphatases. Annu Rev Biochem. 2001; 70: 247–279.
- Leslie NR, Downes CP. PTEN: The down side of PI 3-kinase signalling. Cell Signal. 2002; 14(4): 285–295.
- Shiojima I, Walsh K. Regulation of cardiac growth and coronary angiogenesis by the Akt/PKB signaling pathway. Genes Dev. 2006; 20(24): 3347–3365.
- Vadlakonda L, Dash A, Pasupuleti M, et al. The Paradox of Akt-mTOR Interactions. Front Oncol. 2013; 3: 165.
- Vanhaesebroeck B, Leevers SJ, Ahmadi K, et al. Synthesis and function of 3-phosphorylated inositol lipids. Annu Rev Biochem. 2001; 70: 535–602.
- Park H, Lee S, Shrestha P, et al. AMIGO2, a novel membrane anchor of PDK1, controls cell survival and angiogenesis via Akt activation. J Cell Biol. 2015; 211(3): 619–637.
- Xiao J, Moon M, Yan L, et al. Cellular FLICE-inhibitory protein protects against cardiac remodelling after myocardial infarction. Basic Res Cardiol. 2012; 107(1): 239.
- Sun Y, Yi W, Yuan Y, et al. C1q/tumor necrosis factor-related protein-9, a novel adipocyte-derived cytokine, attenuates adverse remodeling in the ischemic mouse heart via protein kinase A activation. Circulation. 2013; 128(11 Suppl 1): S113–S120.
- Li J, Yuan J. Caspases in apoptosis and beyond. Oncogene. 2008; 27(48): 6194–6206.
- Newmeyer DD, Ferguson-Miller S. Mitochondria: releasing power for life and unleashing the machineries of death. Cell. 2003; 112(4): 481–490.
- Cory S, Adams JM. The Bcl2 family: regulators of the cellular life-or-death switch. Nat Rev Cancer. 2002; 2(9): 647–656.
- Cook SA, Sugden PH, Clerk A. Regulation of bcl-2 family proteins during development and in response to oxidative stress in cardiac myocytes: association with changes in mitochondrial membrane potential. Circ Res. 1999; 85(10): 940–949.
- Misao J, Hayakawa Y, Ohno M, et al. Expression of bcl-2 protein, an inhibitor of apoptosis, and Bax, an accelerator of apoptosis, in ventricular myocytes of human hearts with myocardial infarction. Circulation. 1996; 94(7): 1506–1512.
- Li W, Wang H, Kuang CY, et al. An essential role for the Id1/PI3K/Akt/NFkB/survivin signalling pathway in promoting the proliferation of endothelial progenitor cells in vitro. Mol Cell Biochem. 2012; 363(1-2): 135–145.
- Hussain AR, Ahmed SO, Ahmed M, et al. Cross-talk between NFkB and the PI3-kinase/AKT pathway can be targeted in primary effusion lymphoma (PEL) cell lines for efficient apoptosis. PLoS One. 2012; 7(6): e39945.
