scholarly journals The role of angiotensin signalling in anthracycline-induced cardiotoxicity

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
S Findlay ◽  
C J Plummer ◽  
R Plummer ◽  
J H Gill

Abstract   Anthracyclines (e.g. epirubicin, doxorubicin, daunorubicin) are widely used for the treatment of adult and paediatric cancers. Despite their therapeutic efficacy, anthracyclines are associated with both acute and late-onset cardiac toxicities. Meta-analyses report an overt cardiotoxicity incidence of 6.3%, whilst sub-clinical cardiotoxicity incidence is 17.9% (1). Angiotensin converting enzyme (ACE) inhibitors are used to treat anthracycline-induced cardiotoxicity (AIC) (2) and despite their efficacy being well studied for the treatment of heart failure, hypertension and post-acute coronary syndromes, their mechanism(s) for treating and preventing AIC remain unknown. Using in vitro cardiomyocytes, we evaluated the angiotensin signalling mechanisms stimulated by doxorubicin chemotherapy, applying quantitative PCR, immunofluorescence and real-time cell analysis technologies. In vitro adult human ventricular cardiomyocytes (AC10 cell line) treated with clinically relevant sub-toxic concentrations of doxorubicin, demonstrate a dose and time-dependent increase in angiotensin II type-1 receptor (AT1R) gene expression. Maximal AT1R expression was observed after 24 hours' exposure at 250 nanomolar (nM), with qPCR recording up to 13-fold increases in expression relative to control (figure 1). Consistent with gene expression studies, doxorubicin also induced expression of AT1R at the protein level, with immunofluorescence imaging displaying up-regulation of AT1R in association with doxorubicin concentrations up to 500nM (figure 2). Western blot results also support the induction of AT1R, however no relationship was observed between either doxorubicin concentration or drug exposure time. Cellular growth and morphological changes of cardiomyocytes in response to clinically relevant doses of doxorubicin treatment were evaluated with real-time cell analysis using impedance-based xCELLigence technology. During the early phases of doxorubicin exposure, an increase in cell size was observed, whilst experiments modelling the pharmacokinetics and serial half-lives of doxorubicin demonstrated reversibility of doxorubicin-induced cardiomyocyte injury following drug elimination. These data support the mechanistic hypothesis that a relationship exists between AIC and modulation of the angiotensin signalling pathway in cardiomyocytes. We demonstrate that cardiomyocyte exposure to doxorubicin induces AT1R gene and protein expression, whilst doxorubicin-induced cardiomyocyte injury displays reversibility following drug elimination. Genetic polymorphisms within the ACE gene have been associated with cardiomyopathy and left ventricular hypertrophy. Our research now provides the platform to ascertain whether the ACE genotype contributes to heart failure from AIC, and whether an elevation in pro-hypertrophic angiotensin II levels could exacerbate anthracycline-induced hypertrophy and promote the development of late-onset anthracycline-induced heart failure. FUNDunding Acknowledgement Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Cancer Research UK PhD research grant

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S Findlay ◽  
J.H Gill ◽  
R Plummer ◽  
C.J Plummer

Abstract   Anthracycline chemotherapy remains a key component of cancer treatment regimens in both paediatric and adult patients. A significant issue with their use is the development of anthracycline-induced cardiotoxicity (AIC), with subclinical AIC and clinical heart failure observed in 13.8% and 3.1% of patients, respectively. The major clinical complication of AIC is the development of late-onset cardiotoxicity, occurring several years after drug administration, presenting as life-threatening heart failure (HF). Determining the relationship between subclinical AIC and late-onset HF, strategies for mitigation of AIC, and impacts upon the cancer survivor population remains a complex challenge. Administration of drugs targeting the angiotensin system, specifically angiotensin converting enzyme inhibitors (ACEi), have been reported to reduce AIC in the clinic. Whilst the therapeutic effect of ACEi in management of left ventricular systolic dysfunction and consequent HF is principally through optimisation of cardiac haemodynamics, the mechanism involved with mitigation of late-onset AIC several years after anthracycline exposure are currently unknown. Using a variety of human cardiomyocyte in vitro models we have previously demonstrated induction of cardiomyocyte hypertrophy by angiotensin II and anthracyclines. Importantly, selective blockade of the angiotensin II receptor 1 (ATR1) on cardiomyocytes mitigated the anthracycline-induced hypertrophic response, implicating synergism between AIC and angiotensin signalling in cardiomyocytes. Adult human ventricular cardiac myocyte AC10 cell-line were treated in vitro with a range of clinically relevant doxorubicin doses for clinically appropriate durations, with AT1 receptor gene expression evaluated using semi-quantitative PCR. Our results confirm a positive correlation between clinically-relevant concentration of doxorubicin and induction of genetic expression of ATR1 in AC10 cells, with up to 200% increases in ATR1 expression observed. Maximal doxorubicin-induced gene expression being observed at 8 and 24-hours, respectively. These preliminary results agreeing with clinical exposure parameters for this drug with protein expression studies being optimised to support these gene expression study results. Our preliminary studies also imply patients developing AIC carry a deleted polymorphism within intron 16 of the ACE gene and increased systemic levels of the ACE product angiotensin II, both with a known association to hypertrophic cardiomyopathy. Taken together, these data support our mechanistic hypothesis that a relationship exists between AIC and modulation of the angiotensin signalling pathway in cardiomyocytes, involving structural cellular changes and asymptomatic cardiac hypertrophy. An elevation in angiotensin II levels, potentially through polymorphisms in ACE, could thereby exacerbate anthracycline-induced hypertrophy and promote the development of late-onset anthracycline-induced HF. Funding Acknowledgement Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Cancer Research UK funded PhD


2014 ◽  
Vol 306 (11) ◽  
pp. F1327-F1334 ◽  
Author(s):  
Eva Márquez ◽  
Marta Riera ◽  
Julio Pascual ◽  
María José Soler

Podocytes are key cells in the glomerular filtration barrier with a major role in the development of diabetic nephropathy. Podocytes are insulin-sensitive cells and have a functionally active local renin-angiotensin system. The presence and activity of angiotensin-converting enzyme 2 (ACE2), the main role of which is cleaving profibrotic and proinflammatory angiotensin-II into angiotensin-(1–7), have been demonstrated in podocytes. Conditionally immortalized mouse podocytes were cultured with insulin in the presence and absence of albumin. We found that insulin increases ACE2 gene and protein expression, by real-time PCR and Western blotting, respectively, and enzymatic activity within the podocyte and these increases were maintained over time. Furthermore, insulin favored an “anti-angiotensin II” regarding ACE/ACE2 gene expression balance and decreased fibronectin gene expression as a marker of fibrosis in the podocytes, all studied by real-time PCR. Similarly, insulin incubation seemed to protect podocytes from cell death, studied by a terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay. However, all these effects disappeared in the presence of albumin, which may mimic albuminuria, a main feature of DN pathophysiology. Our results suggest that modulation of renin-angiotensin system balance, fibrosis, and apoptosis by insulin in the podocyte may be an important factor in preventing the development and progression of diabetic kidney disease, but the presence of albuminuria seems to block these beneficial effects.


2007 ◽  
Vol 293 (3) ◽  
pp. H1877-H1882 ◽  
Author(s):  
Gordon S. Huggins ◽  
John J. Lepore ◽  
Sarah Greytak ◽  
Richard Patten ◽  
Rachel McNamee ◽  
...  

Signaling through cAMP plays an important role in heart failure. Phosphorylation of cAMP response element binding protein (CREB) at serine-133 regulates gene expression in the heart. We examined the functional significance of CREB-S133 phosphorylation by comparing transgenic models in which a phosphorylation resistant CREB-S133A mutant containing either an intact or a mutated leucine zipper domain (CREB-S133A-LZ) was expressed in the heart. In vitro, CREB-S133A retained the ability to interact with wild-type CREB, whereas CREB-S133A-LZ did not. In vivo, CREB-S133A and CREB-S133A-LZ were expressed at comparable levels in the heart; however, CREB-S133A markedly suppressed the phosphorylation of endogenous CREB, whereas CREB-S133A-LZ had no effect. The one-year survival of mice from two CREB-S133A-LZ transgenic lines was equivalent to nontransgenic littermate control mice (NTG), whereas transgenic CREB-S133A mice died with heart failure at a median 30 wk of age ( P < 0.0001). CREB-S133A mice had an altered gene expression characteristic of the failing heart, whereas CREB-S133A-LZ mice did not. Left ventricular contractile function was substantially reduced in CREB-S133A mice versus NTG mice and only modestly reduced in CREB-S133A-LZ mice ( P < 0.02). When considered in light of other studies, these findings indicate that overexpression of the CREB leucine zipper is required for both inhibition of endogenous CREB phosphorylation and cardiomyopathy in this murine model of heart failure.


2021 ◽  
Vol 22 (3) ◽  
pp. 1027
Author(s):  
Christian Behm ◽  
Michael Nemec ◽  
Alice Blufstein ◽  
Maria Schubert ◽  
Xiaohui Rausch-Fan ◽  
...  

The periodontal ligament (PDL) responds to applied orthodontic forces by extracellular matrix (ECM) remodeling, in which human periodontal ligament-derived mesenchymal stromal cells (hPDL-MSCs) are largely involved by producing matrix metalloproteinases (MMPs) and their local inhibitors (TIMPs). Apart from orthodontic forces, the synthesis of MMPs and TIMPs is influenced by the aseptic inflammation occurring during orthodontic treatment. Interleukin (IL)-1β is one of the most abundant inflammatory mediators in this process and crucially affects the expression of MMPs and TIMPs in the presence of cyclic low-magnitude orthodontic tensile forces. In this study we aimed to investigate, for the first time, how IL-1β induced expression of MMPs, TIMPs and how IL-1β in hPDL-MSCs was changed after applying in vitro low-magnitude orthodontic tensile strains in a static application mode. Hence, primary hPDL-MSCs were stimulated with IL-1β in combination with static tensile strains (STS) with 6% elongation. After 6- and 24 h, MMP-1, MMP-2, TIMP-1 and IL-1β expression levels were measured. STS alone had no influence on the basal expression of investigated target genes, whereas IL-1β caused increased expression of these genes. In combination, they increased the gene and protein expression of MMP-1 and the gene expression of MMP-2 after 24 h. After 6 h, STS reduced IL-1β-induced MMP-1 synthesis and MMP-2 gene expression. IL-1β-induced TIMP-1 gene expression was decreased by STS after 6- and 24-h. At both time points, the IL-1β-induced gene expression of IL-1β was increased. Additionally, this study showed that fetal bovine serum (FBS) caused an overall suppression of IL-1β-induced expression of MMP-1, MMP-2 and TIMP-1. Further, it caused lower or opposite effects of STS on IL-1β-induced expression. These observations suggest that low-magnitude orthodontic tensile strains may favor a more inflammatory and destructive response of hPDL-MSCs when using a static application form and that this response is highly influenced by the presence of FBS in vitro.


2021 ◽  
Vol 22 (3) ◽  
pp. 1343
Author(s):  
Hye Hyeon Yun ◽  
Soon Young Jung ◽  
Bong Woo Park ◽  
Ji Seung Ko ◽  
Kyunghyun Yoo ◽  
...  

BCL-2 interacting cell death suppressor (BIS) is a multifunctional protein that has been implicated in cancer and myopathy. Various mutations of the BIS gene have been identified as causative of cardiac dysfunction in some dilated cardiomyopathy (DCM) patients. This was recently verified in cardiac-specific knock-out (KO) mice. In this study, we developed tamoxifen-inducible cardiomyocyte-specific BIS-KO (Bis-iCKO) mice to assess the role of BIS in the adult heart using the Cre-loxP strategy. The disruption of the Bis gene led to impaired ventricular function and subsequent heart failure due to DCM, characterized by reduced left ventricular contractility and dilatation that were observed using serial echocardiography and histology. The development of DCM was confirmed by alterations in Z-disk integrity and increased expression of several mRNAs associated with heart failure and remodeling. Furthermore, aggregation of desmin was correlated with loss of small heat shock protein in the Bis-iCKO mice, indicating that BIS plays an essential role in the quality control of cardiac proteins, as has been suggested in constitutive cardiac-specific KO mice. Our cardiac-specific BIS-KO mice may be a useful model for developing therapeutic interventions for DCM, especially late-onset DCM, based on the distinct phenotypes and rapid progressions.


2011 ◽  
Vol 13 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Luciana G Pereira ◽  
Carine P Arnoni ◽  
Edgar Maquigussa ◽  
Priscila C Cristovam ◽  
Juliana Dreyfuss ◽  
...  

The prorenin receptor [(P)RR] is upregulated in the diabetic kidney and has been implicated in the high glucose (HG)-induced overproduction of profibrotic molecules by mesangial cells (MCs), which is mediated by ERK1/2 phosphorylation. The regulation of (P)RR gene transcription and the mechanisms by which HG increases (P)RR gene expression are not fully understood. Because intracellular levels of angiotensin II (AngII) are increased in MCs stimulated with HG, we used this in vitro system to evaluate the possible role of AngII in (P)RR gene expression and function by comparing the effects of AT1 receptor blockers (losartan or candesartan) and (P)RR mRNA silencing (siRNA) in human MCs (HMCs) stimulated with HG. HG induced an increase in (P)RR and fibronectin expression and in ERK1/2 phosphorylation. These effects were completely reversed by (P)RR siRNA and losartan but not by candesartan (an angiotensin receptor blocker that, in contrast to losartan, blocks AT1 receptor internalization). These results suggest that (P)RR gene activity may be controlled by intracellular AngII and that HG-induced ERK1/2 phosphorylation and fibronectin overproduction are primarily induced by (P)RR activation. This relationship between AngII and (P)RR may constitute an additional pathway of MC dysfunction in response to HG stimulation.


2013 ◽  
Vol 115 (10) ◽  
pp. 1572-1580 ◽  
Author(s):  
Vigdis Hillestad ◽  
Frank Kramer ◽  
Stefan Golz ◽  
Andreas Knorr ◽  
Kristin B. Andersson ◽  
...  

In human heart failure (HF), reduced cardiac function has, at least partly, been ascribed to altered calcium homeostasis in cardiomyocytes. The effects of the calcium sensitizer levosimendan on diastolic dysfunction caused by reduced removal of calcium from cytosol in early diastole are not well known. In this study, we investigated the effect of long-term levosimendan treatment in a murine model of HF where the sarco(endo)plasmatic reticulum ATPase ( Serca) gene is specifically disrupted in the cardiomyocytes, leading to reduced removal of cytosolic calcium. After induction of Serca2 gene disruption, these mice develop marked diastolic dysfunction as well as impaired contractility. SERCA2 knockout (SERCA2KO) mice were treated with levosimendan or vehicle from the time of KO induction. At the 7-wk end point, cardiac function was assessed by echocardiography and pressure measurements. Vehicle-treated SERCA2KO mice showed significantly diminished left-ventricular (LV) contractility, as shown by decreased ejection fraction, stroke volume, and cardiac output. LV pressure measurements revealed a marked increase in the time constant (τ) of isovolumetric pressure decay, showing impaired relaxation. Levosimendan treatment significantly improved all three systolic parameters. Moreover, a significant reduction in τ toward normalization indicated improved relaxation. Gene-expression analysis, however, revealed an increase in genes related to production of the ECM in animals treated with levosimendan. In conclusion, long-term levosimendan treatment improves both contractility and relaxation in a heart-failure model with marked diastolic dysfunction due to reduced calcium transients. However, altered gene expression related to fibrosis was observed.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Sven T Pleger ◽  
Changguang Shan ◽  
Jan Kziencek ◽  
Oliver Mueller ◽  
Raffi Bekeredjian ◽  
...  

Background: Cardiac expression of the Ca-dependent inotropic protein S100A1 is decreased in human end-stage heart failure (HF) and cardiomyocyte-targeted viral-based S100A1 gene transfer rescued failing myocardium in small animal models in vivo and in vitro via improved systolic and diastolic sarcoplasmic reticulum Ca-handling. We therefore hypothesized that cardioselective AAV9-S100A1 gene therapy will improve cardiac performance in a large animal experimental HF model under clinical conditions. Methods and Results: Left ventricular (LV) posterolateral myocardial infarction (MI) was induced in pigs by occlusion of the left coronary circumflex artery and resulted in LV failure (HF) 2 weeks post-MI reflected by a 40% and 27% reduction in LV +dp/dt max. and EF, respectively, as assessed by LV catheterization and echocardiography. Post-MI HF pigs were then randomized for retroinfusion of AAV9-luciferase (luc; n=6, 1.5×10 13 total viral particles, tvp) and AAV9-S100A1 (S100A1; n=6, 1.5×10 13 tvp) driven by a cardioselective promoter via the anterior cardiac vein while the left anterior descending artery was temporarily occluded. 14 weeks after cardiac gene transfer, the S100A1-treated HF group showed significantly enhanced S100A1 protein expression (+46.7±17.9%, P<0.05 vs. control groups) in targeted remote LV myocardium and improved indices of cardiac function and remodeling (luc vs. S100A1: +dp/dtmax: 983±81 vs. 1526±83 mmHg/s, EF: 39±2.1 vs. 61±3.7 %, P<0.05 S100A1 vs. luc, LV endsystolic diameter: luc 4.45±0.1 vs. S100A1 3.43 ±0.1 cm, P<0.05 S100A1 vs. luc, HR: 72±4 vs. 69±2, beats/min, P=n.s. S100A1 vs. luc). Importantly, analyses of renal, hepatic and hematopoetic function showed no alteration as assessed by unchanged transaminases, retention values and white blood cell counts compared to sham pigs. Conclusions: Our translational study provides proof of concept that AAV9-S100A1 based HF gene therapy is feasible and restores cardiac function in a large animal HF model under clinical conditions. Next, certified toxicological analysis and different AAV9-S100A1 dosage protocols will be assessed to eventually advance to first phase I/II clinical studies determining therapeutic efficiency of cardiac S100A1 gene therapy in HF patients.


2011 ◽  
Vol 109 (suppl_1) ◽  
Author(s):  
Marie Schroeder ◽  
Angus Z Lau ◽  
Albert P Chen ◽  
Jennifer Barry ◽  
Damian J Tyler ◽  
...  

Disordered metabolic substrate utilisation has been implicated in the pathogenesis of heart failure (HF). Hyperpolarised (HYP) 13C magnetic resonance, a technique in which the fate of 13C-labelled metabolites can be followed using MR imaging or spectroscopy, has enabled non-invasive assessment of metabolism. The aim of this study was to monitor carbohydrate metabolism alongside cardiac structure, function, and energetics, throughout HF progression. HF was induced in pigs (n=5) by right ventricular pacing at 188 bpm for 5 weeks. Pigs were examined at weekly time points: cine MRI assessed cardiac structure and function, HYP 13C2-pyruvate was administered intravenously and 13C MRS was used to assess 13C-glutamate production via Krebs cycle, 31P MRS assessed myocardial energetics, and HYP 13C1-pyruvate was administered to enable MRI of H13CO3- production from pyruvate dehydrogenase (PDH). At baseline, pigs had a normal left ventricular (LV) cardiac index (CI) and end diastolic volume (EDVi). The PCr/ATP was 2.3 ± 0.2. The 13C-glutamate/13C2-pyruvate was 4.3 ± 0.9%, and the H13CO3-/13C1-pyruvate ratio was 1.6 ± 0.2%. After 1–2 weeks of pacing, CI decreased to 3.3 ± 0.5 l/min/m2, PCr/ATP decreased to 1.7 ± 0.1, and 13C-glutamate/13C2-pyruvate decreased to 2.1 ± 0.6%. With the onset of HF, EDVi increased to 140.3 ± 14.1 ml/m2 and H13CO3-/13C1-pyruvate decreased to 0.5 ± 0.2%. In conclusion, we observed an early defect in Krebs' cycle that occurred alongside impaired cardiac energetics and function. Carbohydrate oxidation via PDH was maintained until the onset of HF. These results encourage use of metabolic therapies to delay/prevent the onset of heart failure in patients.


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