scholarly journals p47phox-Dependent Oxidant Signalling through ASK1, MKK3/6 and MAPKs in Angiotensin II-Induced Cardiac Hypertrophy and Apoptosis

Antioxidants ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1363
Author(s):  
Fangfei Liu ◽  
Lampson M. Fan ◽  
Li Geng ◽  
Jian-Mei Li
Keyword(s):  
Angiotensin Ii ◽  
Cardiac Hypertrophy ◽  
Cardiomyocyte Apoptosis ◽  
Regulatory Subunit ◽  
Signalling Pathways ◽  
Oxygen Species ◽  
Pathological Changes ◽  
Wild Type ◽  
Elevated Expression ◽  
Significant Activation

The p47phox is a key regulatory subunit of Nox2-containing NADPH oxidase (Nox2) that by generating reactive oxygen species (ROS) plays an important role in Angiotensin II (AngII)-induced cardiac hypertrophy and heart failure. However, the signalling pathways of p47phox in the heart remains unclear. In this study, we used wild-type (WT) and p47phox knockout (KO) mice (C57BL/6, male, 7-month-old, n = 9) to investigate p47phox-dependent oxidant-signalling in AngII infusion (0.8 mg/kg/day, 14 days)-induced cardiac hypertrophy and cardiomyocyte apoptosis. AngII infusion resulted in remarkable high blood pressure and cardiac hypertrophy in WT mice. However, these AngII-induced pathological changes were significantly reduced in p47phox KO mice. In WT hearts, AngII infusion increased significantly the levels of superoxide production, the expressions of Nox subunits, the expression of PKCα and C-Src and the activation of ASK1 (apoptosis signal-regulating kinase 1), MKK3/6, ERK1/2, p38 MAPK and JNK signalling pathways together with an elevated expression of apoptotic markers, i.e., γH2AX and p53 in the cardiomyocytes. However, in the absence of p47phox, although PKCα expression was increased in the hearts after AngII infusion, there was no significant activation of ASK1, MKK3/6 and MAPKs signalling pathways and no increase in apoptosis biomarker expression in cardiomyocytes. In conclusion, p47phox-dependent redox-signalling through ASK1, MKK3/6 and MAPKs plays a crucial role in AngII-induced cardiac hypertrophy and cardiomyocyte apoptosis.

Abstract 478: FGF23 Expression in Cardiac Fibroblasts Is Augmented by S100/Calgranulins-Mediated Inflammation and Associated With Cardiac Hypertrophy, but Not in Angiotensin II-Induced Cardiac Hypertrophy

2015 ◽  
Vol 35 (suppl_1) ◽  
Author(s):  
Marion Hofmann Bowman ◽  
Brandon Gardner ◽  
Judy Earley ◽  
Debra L Rateri ◽  
Alan Daugherty ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Cardiac Hypertrophy ◽  
Cardiac Fibroblasts ◽  
Left Ventricular ◽  
Heart Weight ◽  
Ang Ii ◽  
Wild Type ◽  
Wild Type Littermate ◽  
Transgenic Expression ◽  
Significant Difference

Background: Serum S100A12 and fibroblast growth factor (FGF) 23 are biomarkers for cardiovascular mortality in patients with chronic kidney disease (CKD) and are associated with left ventricular hypertrophy (LVH). FGF23 is induced in cultured cardiac fibroblasts in response to cytokines including IL-6, TNF-a, LPS and S100/calgranulins. Moreover, hBAC-S100 transgenic mice with CKD had increased FGF23 in valvular interstitial cells and exhibited LVH. The present study was designed to examine cardiac FGF23 expression in other murine models of LVH in the absence of CKD. Methods: Hearts from five groups of male mice were studied: (i) C57BL6/J with transgenic expression a bacterial artificial chromosome of the human S100/calgranulins (S1008/9 and S100A12, hBAC-S100), (ii) wild type littermates, (iii) LDLR-/- infused with saline (29 days, 0.9%), (iv) LDLR-/- infused with angiotensin (Ang) II (29 days, 1000 ng/kg/min), and (v) fibroblast specific depletion of angiotensin II type 1a receptor (AT1aR) (S100A4-Cre x AT1aR-/- x LDLR-/-) infused with AngII. Results: hBAC-S100, but not wild type littermate mice, developed significant LVH at 10 months by heart weight/body weight (5.9 ±1.1 mg/g vs. 4.2 ±0.8, p<0.04), decreased E/A ratio, and increased LVPW thickness, and associated with increased expression of FGF23 mRNA and protein in cardiac tissue lysates (2-4 fold increase). Similarly, Ang II induced significant LVH compared to saline infused LDLR-/- mice (6.1±1.3 vs. 3.6 ±0.9 mg/g, p<0.01), and associated with increased mRNA for hypertrophic genes (ANP, BNP, b-MHC, CTGF and Col1a1). However, there was no significant difference in FGF23 mRNA and protein between Ang II and saline infused mice. Cardiac hypertrophy was attenuated in AngII-infused mice with deficiency of AT1aR (S100A4-Cre+/-xAT1aRxLDLR-/-). In vitro, Ang II (100nM) did not induce FGF23 in valvular interstitial fibroblasts or myocytes. Summary: Transgenic expression of S100/calgranulins is sufficient to induce LVH in aged mice with normal renal function, and this is associated with FGF23 expression in cardiac interstitial fibroblasts. Future studies are needed to determine whether cardiac FGF23 promotes LVH in a paracrine manner. However, FGF23 does not play a role in Ang II-induced LVH.

Abstract 066: Cyclooxygenase-depended Signaling Via Thromboxane Prostanoid Receptors Mediates Endothelin-i Induced Ros Generation In Mesenteric Resistance Vessels From Mice Infused With Angiotensin Ii

Hypertension ◽  
2014 ◽  
Vol 64 (suppl_1) ◽  
Author(s):  
Christopher S Wilcox ◽  
Cheng Wang ◽  
Dan Wang
Keyword(s):  
Reactive Oxygen Species ◽  
Angiotensin Ii ◽  
Ros Generation ◽  
Oxygen Species ◽  
Ang Ii ◽  
Wild Type ◽  
Prostanoid Receptors ◽  
Resistance Vessels ◽  
Cox 2 ◽  
Cox 1

Background: Angiotensin II (Ang II) increases reactive oxygen species (ROS) and contractions to thromboxane and endothelin-1 (ET-1). Therefore, we tested the hypothesis that cyclooxygenase (COX) and/or thromboxane-prostanoid receptors (TP-Rs) mediate enhanced ROS generations with ET-1 in Ang II-infused mice. Methods: ROS was assessed by urinary 8-isoprotane(8-Iso) excretion and ethedium : dihydroetheldium (DHE) in mesenteric resistance arterioles (MRAs) from wild type (+/+) and littermate COX-1 -/- or TP-R -/- mice infused with vehicle or angiotensin II (Ang II, 400 ng/kg/min for 14 days) (n=6/ group, mean ±SEM). Results: Ang II infusion increased excretion (ng/mg creatine) of TxB 2 (1.3±0.1±1.0±0.1 in COX-1 +/+ mice and 1.9±0.1 vs 1.2±0.1 in TP-R +/+ mice, all P<0.05) and 8-Iso (2.1±0.2 vs 1.4±0.1 in COX-1 +/+ mice and 2.2±0.1 vs 1.4±0.2 in TP-R +/+ mice, all P<0.05) but not in COX-1 -/- or TP-R -/- mice. Ang II enhanced ROS generation (Δunit) with 10 -7 M ET-1 in MRAs from both +/+ mouse genotypes (1.7±0.2 vs 0.1±0.1 in COX-1 +/+ mice and 3.2±0.3 vs 0.1±0.1 in TP-R +/+ mice, all P<0.01). However, this increase in ROS was fully prevented in TP-R-/- mouse vessels (0.3±0.2 vs 0.2±0.1, NS) and in COX-1 +/+ mouse vessels after combined blockade of COX-1( 10 -5 M SC-560) and -2 (paracoxib 10 -5 M) (0.2±0.1 vs 0.1±0.1, NS) and in COX-1 -/- mouse vessels after paracoxib (0.2±0.1 vs 0.2±0.2, NS). Increased ROS generation was only partially prevented in COX-1 -/- mouse vessels (0.5±0.1 vs 0.2±0.2, P<0.05) or in COX-1 +/+ mouse vessels after blockade of COX-1 ( 0.7±0.1 vs 0.1±0.1, NS) or COX-2 (1.0±0.1 vs 0.1±0.1,P<0.05). Conclusions: Increased ROS generation with ET-1 in microvessels from Ang II infused mice depends on products of both COX-1 and -2 that activate TP-Rs. Thus, combined blockade of COX-1 and -2 or TP-Rs may prevent vascular ROS and its many complications during increased Ang II and ET-1, such as hypertension, hypoxia or shock.

scholarly journals CCR2 mediates the uptake of bone marrow-derived fibroblast precursors in angiotensin II-induced cardiac fibrosis

2011 ◽  
Vol 301 (2) ◽  
pp. H538-H547 ◽  
Author(s):  
Jing Xu ◽  
Song-Chang Lin ◽  
Jiyuan Chen ◽  
Yuanxin Miao ◽  
George E. Taffet ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Angiotensin Ii ◽  
Cardiac Hypertrophy ◽  
Knockout Mice ◽  
Molecular Mechanisms ◽  
Cardiac Fibrosis ◽  
Systolic Function ◽  
Left Ventricular ◽  
Collagen I ◽  
Wild Type

Angiotensin II plays an important role in the development of cardiac hypertrophy and fibrosis, but the underlying cellular and molecular mechanisms are not completely understood. Recent studies have shown that bone marrow-derived fibroblast precursors are involved in the pathogenesis of cardiac fibrosis. Since bone marrow-derived fibroblast precursors express chemokine receptor, CCR2, we tested the hypothesis that CCR2 mediates the recruitment of fibroblast precursors into the heart, causing angiotensin II-induced cardiac fibrosis. Wild-type and CCR2 knockout mice were infused with angiotensin II at 1,500 ng·kg−1·min−1. Angiotensin II treatment resulted in elevated blood pressure and cardiac hypertrophy that were not significantly different between wild-type and CCR2 knockout mice. Angiotensin II treatment of wild-type mice caused prominent cardiac fibrosis and accumulation of bone marrow-derived fibroblast precursors expressing the hematopoietic markers, CD34 and CD45, and the mesenchymal marker, collagen I. However, angiotensin II-induced cardiac fibrosis and accumulation of bone marrow-derived fibroblast precursors in the heart were abrogated in CCR2 knockout mice. Furthermore, angiotensin II treatment of wild-type mice increased the levels of collagen I, fibronectin, and α-smooth muscle actin in the heart, whereas these changes were not observed in the heart of angiotensin II-treated CCR2 knockout mice. Functional studies revealed that the reduction of cardiac fibrosis led to an impairment of cardiac systolic function and left ventricular dilatation in angiotensin II-treated CCR2 knockout mice. Our data demonstrate that CCR2 plays a pivotal role in the pathogenesis of angiotensin II-induced cardiac fibrosis through regulation of bone marrow-derived fibroblast precursors.

Mice expressing ACE only in the heart show that increased cardiac angiotensin II is not associated with cardiac hypertrophy

2008 ◽  
Vol 294 (2) ◽  
pp. H659-H667 ◽  
Author(s):  
Hong D. Xiao ◽  
Sebastien Fuchs ◽  
Ellen A. Bernstein ◽  
Ping Li ◽  
Duncan J. Campbell ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Cardiac Hypertrophy ◽  
Connexin 43 ◽  
Left Ventricular ◽  
Compound Heterozygous ◽  
Moderate Increase ◽  
Wild Type ◽  
Aortic Banding ◽  
Atrial Enlargement ◽  
Normal Cardiac Function

In the heart, angiotensin II has been suggested to regulate cardiac remodeling and promote cardiac hypertrophy. To examine this, we studied compound heterozygous mice, called angiotensin-converting enzyme (ACE) 1/8, in which one ACE allele is null, whereas the other ACE allele (the 8 allele) targets expression to the heart. In this model, cardiac ACE levels are about 15 times those of wild-type mice, and ACE expression is reduced or eliminated in other tissues. ACE 1/8 mice have 58% the cardiac ACE of a previous model, called ACE 8/8, but both ACE 1/8 and ACE 8/8 mice have ventricular angiotensin II levels about twofold those of wild-type controls. Despite equivalent levels of cardiac angiotensin II, ACE 1/8 mice do not develop the marked atrial enlargement or the conduction defects previously reported in the ACE 8/8 mice. Six-month-old ACE 1/8 mice have normal cardiac function, as determined by echocardiography and left ventricular catheterization, despite the elevated levels of angiotensin II. ACE 1/8 mice also have normal levels of connexin 43. Both wild-type and ACE 1/8 mice develop similar degrees of cardiac hypertrophy after aortic banding. These data suggest that a moderate increase of local angiotensin II production in the heart does not produce cardiac dysfunction, at least under basal conditions, and that, in response to aortic banding, cardiac hypertrophy is not augmented by a twofold increase of cardiac angiotensin II.

scholarly journals Cardiovascular homeostasis dependence on MICU2, a regulatory subunit of the mitochondrial calcium uniporter

2017 ◽  
Vol 114 (43) ◽  
pp. E9096-E9104 ◽  
Author(s):  
Alexander G. Bick ◽  
Hiroko Wakimoto ◽  
Kimberli J. Kamer ◽  
Yasemin Sancak ◽  
Olga Goldberger ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Aortic Rupture ◽  
Systolic Dysfunction ◽  
Regulatory Subunit ◽  
Aortic Tissue ◽  
Mitochondrial Calcium ◽  
Rna Seq ◽  
Wild Type ◽  
Mitochondrial Calcium Uniporter ◽  
Calcium Uniporter

Comparative analyses of transcriptional profiles from humans and mice with cardiovascular pathologies revealed consistently elevated expression of MICU2, a regulatory subunit of the mitochondrial calcium uniporter complex. To determine if MICU2 expression was cardioprotective, we produced and characterized Micu2−/− mice. Mutant mice had left atrial enlargement and Micu2−/− cardiomyocytes had delayed sarcomere relaxation and cytosolic calcium reuptake kinetics, indicating diastolic dysfunction. RNA sequencing (RNA-seq) of Micu2−/− ventricular tissues revealed markedly reduced transcripts encoding the apelin receptor (Micu2−/− vs. wild type, P = 7.8 × 10−40), which suppresses angiotensin II receptor signaling via allosteric transinhibition. We found that Micu2−/− and wild-type mice had comparable basal blood pressures and elevated responses to angiotensin II infusion, but that Micu2−/− mice exhibited systolic dysfunction and 30% lethality from abdominal aortic rupture. Aneurysms and rupture did not occur with norepinephrine-induced hypertension. Aortic tissue from Micu2−/− mice had increased expression of extracellular matrix remodeling genes, while single-cell RNA-seq analyses showed increased expression of genes related to reactive oxygen species, inflammation, and proliferation in fibroblast and smooth muscle cells. We concluded that Micu2−/− mice recapitulate features of diastolic heart disease and define previously unappreciated roles for Micu2 in regulating angiotensin II-mediated hypertensive responses that are critical in protecting the abdominal aorta from injury.

scholarly journals Role of Nox isoforms in angiotensin II-induced oxidative stress and endothelial dysfunction in brain

2012 ◽  
Vol 113 (2) ◽  
pp. 184-191 ◽  
Author(s):  
Sophocles Chrissobolis ◽  
Botond Banfi ◽  
Christopher G. Sobey ◽  
Frank M. Faraci
Keyword(s):  
Oxidative Stress ◽  
Angiotensin Ii ◽  
Endothelial Dysfunction ◽  
Minor Role ◽  
Oxygen Species ◽  
Ang Ii ◽  
Wild Type ◽  
Vascular Beds ◽  
A Minor

Angiotensin II (Ang II) promotes vascular disease through several mechanisms including by producing oxidative stress and endothelial dysfunction. Although multiple potential sources of reactive oxygen species exist, the relative importance of each is unclear, particularly in individual vascular beds. In these experiments, we examined the role of NADPH oxidase (Nox1 and Nox2) in Ang II-induced endothelial dysfunction in the cerebral circulation. Treatment with Ang II (1.4 mg·kg−1·day−1 for 7 days), but not vehicle, increased blood pressure in all groups. In wild-type (WT; C57Bl/6) mice, Ang II reduced dilation of the basilar artery to the endothelium-dependent agonist acetylcholine compared with vehicle but had no effect on responses in Nox2-deficient (Nox2−/y) mice. Ang II impaired responses to acetylcholine in Nox1 WT (Nox1+/y) and caused a small reduction in responses to acetylcholine in Nox1-deficient (Nox1−/y) mice. Ang II did not impair responses to the endothelium-independent agonists nitroprusside or papaverine in either group. In WT mice, Ang II increased basal and phorbol-dibutyrate-stimulated superoxide production in the cerebrovasculature, and these increases were abolished in Nox2−/y mice. Overall, these data suggest that Nox2 plays a relatively prominent role in mediating Ang II-induced oxidative stress and cerebral endothelial dysfunction, with a minor role for Nox1.

scholarly journals Endothelin-1-Induced Microvascular ROS and Contractility in Angiotensin-II-Infused Mice Depend on COX and TP Receptors

Antioxidants ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 193 ◽  
Author(s):  
Christopher S. Wilcox ◽  
Cheng Wang ◽  
Dan Wang
Keyword(s):  
Angiotensin Ii ◽  
Nadph Oxidase ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Ros Generation ◽  
Oxygen Species ◽  
Ang Ii ◽  
Wild Type ◽  
Endothelin 1 ◽  
Ros Metabolism ◽  
Tp Receptors

(1) Background: Angiotensin II (Ang II) and endothelin 1 (ET-1) generate reactive oxygen species (ROS) that can activate cyclooxygenase (COX). However, thromboxane prostanoid receptors (TPRs) are required to increase systemic markers of ROS during Ang II infusion in mice. We hypothesized that COX and TPRs are upstream requirements for the generation of vascular ROS by ET-1. (2) Methods: ET-1-induced vascular contractions and ROS were assessed in mesenteric arterioles from wild type (+/+) and knockout (−/−) of COX1 or TPR mice infused with Ang II (400 ng/kg/min × 14 days) or a vehicle. (3) Results: Ang II infusion appeared to increase microvascular protein expression of endothelin type A receptors (ETARs), TPRs, and COX1 and 2 in COX1 and TPR +/+ mice but not in −/− mice. Ang II infusion increased ET-1-induced vascular contractions and ROS, which were prevented by a blockade of COX1 and 2 in TPR +/+ mice. ET-1 increased the activity of aortic nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and decreased superoxide dismutase (SOD) 1, 2, and 3 in Ang-II-infused mice, which were prevented by a blockade of TPRs. (4) Conclusion: Activation of vascular TPRs by COX products are required for ET-1 to increase vascular contractions and ROS generation from NADPH oxidase and reduce ROS metabolism by SOD. These effects require an increase in these systems by prior infusion of Ang II.

scholarly journals TLR2 signaling pathway combats Streptococcus uberis infection by inducing production of mitochondrial reactive oxygen species

2019 ◽  
Author(s):  
Bin Li ◽  
Zhixin Wan ◽  
Zhenglei Wang ◽  
Jiakun Zuo ◽  
Yuanyuan Xu ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Signaling Pathways ◽  
Host Defense ◽  
Proinflammatory Cytokines ◽  
Mammary Glands ◽  
Oxygen Species ◽  
Mitochondrial Reactive Oxygen Species ◽  
Pathological Changes ◽  
Wild Type ◽  
Streptococcus Uberis

AbstractMastitis caused by Streptococcus uberis is a hazardous clinical disease in dairy animals. In this study, the role of Toll-like receptors (TLRs) and TLR-mediated signaling pathways in mastitis caused by S. uberis was investigated using mouse models and mammary epithelial cells (MECs). We used S. uberis to infect mammary glands of wild type, TLR2−/− and TLR4−/− mice and quantified the adaptor molecules in TLR signaling pathways, proinflammatory cytokines, tissue damage and bacterial count in mammary glands. When compared with TLR4 deficiency, TLR2 deficiency induced more severe pathological changes through myeloid differentiation primary response 88 (MyD88)-mediated signaling pathways during S. uberis infection. In MECs, TLR2 detected S. uberis infection and induced mitochondrial reactive oxygen species (mROS) to assist host control of secretion of inflammatory factors and elimination of intracellular S. uberis. Our results demonstrate that TLR2-mediated mROS have a significant effect on S. uberis-induced host defense responses in mammary glands as well as MECs.Author summaryS. uberis contributes significantly to global mastitis and remains a major obstacle for inflammation elimination due to its ability to form persistent infection in mammary tissue. The Toll-like receptor (TLR) family plays a significant role in identifying infections of intracellular bacteria and further triggering inflammatory reactions in immune cells. However, the detailed molecular mechanism by which TLR is regulated, and whether MECs, as the main cells in mammary gland, are tightly involved in these processes is poorly understood. Here, we used S. uberis to infect mammary glands of wild type, TLR2−/−, TLR4−/− mice and MECs to assess pathogenesis, proinflammatory cytokines, ROS as well as mROS levels during infection. We found that during S.uberis infection, it is TLR2 deficiency that induced more severe pathological changes through MyD88-mediated signaling pathways. In addition, our work demonstrates that mROS mediated by TLR2 has an important role in host defense response to combat S. uberis infection in mammary glands as well as MECs.

Cooperative interaction between reactive oxygen species and Ca2+ signals contributes to angiotensin II-induced hypertrophy in adult rat cardiomyocytes

2012 ◽  
Vol 302 (4) ◽  
pp. H901-H909 ◽  
Author(s):  
Rukhsana Gul ◽  
Asif Iqbal Shawl ◽  
Suhn-Hee Kim ◽  
Uh-Hyun Kim
Keyword(s):  
Reactive Oxygen Species ◽  
Angiotensin Ii ◽  
Cardiac Hypertrophy ◽  
Reactive Oxygen ◽  
Ros Production ◽  
Oxygen Species ◽  
Ang Ii ◽  
Rat Cardiomyocytes ◽  
Adult Rat ◽  
Adp Ribosyl Cyclase

Reactive oxygen species (ROS) and Ca2+ signals are closely associated with the pathogenesis of cardiac hypertrophy. However, the cause and effect of the two signals in cardiac hypertrophy remain to be clarified. We extend our recent report by investigating a potential interaction between ROS and Ca2+ signals utilizing in vitro and in vivo angiotensin II (ANG II)-induced cardiac hypertrophy models. ANG II-induced initial Ca2+ transients mediated by inositol trisphosphate (IP3) triggered initial ROS production in adult rat cardiomyocytes. The ROS generated by activation of the NAD(P)H oxidase complex via Rac1 in concert with Ca2+ activates ADP-ribosyl cyclase to generate cyclic ADP-ribose (cADPR). This messenger-mediated Ca2+ signal further augments ROS production, since 2,2′-dihydroxyazobenzene, an ADP-ribosyl cyclase inhibitor, or 8-Br-cADPR, an antagonistic analog of cADPR, abolished further ROS production. Data from short hairpin RNA (shRNA)-mediated knockdown of Akt1 and p47phox demonstrated that Akt1 is the upstream key molecule responsible for the initiation of Ca2+ signal that activates p47phox to generate ROS in cardiomyocytes. Nuclear translocation of nuclear factor of activated T-cell in cardiomyocytes was significantly suppressed by treatment with NAD(P)H oxidase inhibitors as well as by shRNA against Akt1 and p47phox. Our results suggest that in cardiomyocytes Ca2+ and ROS messengers generated by ANG II amplify the initial signals in a cooperative manner, thereby leading to cardiac hypertrophy.

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