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1.  Metabolic Gene Remodeling and Mitochondrial Dysfunction in Failing Right Ventricular Hypertrophy due to Pulmonary Arterial Hypertension 
Circulation. Heart failure  2012;6(1):136-144.
Background
Right ventricular dysfunction (RVD) is the most frequent cause of death in patients with pulmonary arterial hypertension. Whereas abnormal energy substrate utilization has been implicated in the development of chronic left heart failure, data describing such metabolic remodeling in RVD remain incomplete. Thus, we sought to characterize metabolic gene expression changes and mitochondrial dysfunction in functional and dysfunctional RV hypertrophy.
Methods and Results
Two different rat models of RV hypertrophy were studied. The model of RVD (SU5416/hypoxia) exhibited a significantly decreased gene expression of PPAR-gamma coactivator-1 alpha (PGC-1α), PPAR-α and ERR-α. The expression of multiple PCG-1α target genes required for fatty acid oxidation (FAO) was similarly decreased. Decreased PGC-1α expression was also associated with a net loss of mitochondrial protein and oxidative capacity. Reduced mitochondrial number was associated with a downregulation of TFAM and other genes required for mitochondrial biogenesis. Electron microscopy demonstrated that in RVD tissue, mitochondria had abnormal shape and size. Lastly, respirometric analysis demonstrated that mitochondria isolated from RVD-tissue had a significantly reduced ADP-stimulated (state 3) rate for complex I. Conversely, functional RV hypertrophy in the pulmonary artery banding (PAB) model showed normal expression of PGC-1α, whereas the expression of FAO genes was either preserved or unregulated. Moreover, PAB-RV tissue exhibited preserved TFAM expression and mitochondrial respiration despite elevated RV pressure-overload.
Conclusions
Right ventricular dysfunction, but not functional RV hypertrophy in rats, demonstrates a gene expression profile compatible with a multilevel impairment of fatty acid metabolism and significant mitochondrial dysfunction, partially independent of chronic pressure-overload.
doi:10.1161/CIRCHEARTFAILURE.111.966127
PMCID: PMC3790960  PMID: 23152488
pulmonary heart disease; metabolism; pressure; fatty acids; mitochondria
2.  Interleukin-1 Blockade With Anakinra to Prevent Adverse Cardiac Remodeling After Acute Myocardial Infarction (Virginia Commonwealth University Anakinra Remodeling Trial [VCU-ART] Pilot Study) 
The American journal of cardiology  2013;111(10):1394-1400.
Acute myocardial infarction (AMI) initiates an intense inflammatory response in which interleukin-1 (IL-1) plays a central role. The IL-1 receptor antagonist is a naturally occurring antagonist, and anakinra is the recombinant form used to treat inflammatory diseases. The aim of the present pilot study was to test the safety and effects of IL-1 blockade with anakinra on left ventricular (LV) remodeling after AMI. Ten patients with ST-segment elevation AMI were randomized to either anakinra 100 mg/day subcutaneously for 14 days or placebo in a double-blind fashion. Two cardiac magnetic resonance (CMR) imaging and echocardiographic studies were performed during a 10- to 14-week period. The primary end point was the difference in the interval change in the LV end-systolic volume index (LVESVi) between the 2 groups on CMR imaging. The secondary end points included differences in the interval changes in the LV end-diastolic volume index, and C-reactive protein levels. A +2.0 ml/m2 median increase (interquartile range +1.0, +11.5) in the LVESVi on CMR imaging was seen in the placebo group and a –3.2 ml/m2 median decrease (interquartile range –4.5, –1.6) was seen in the anakinra group (p = 0.033). The median difference was 5.2 ml/m2. On echocardiography, the median difference in the LVESVi change was 13.4 ml/m2 (p = 0.006). Similar differences were observed in the LV end-diastolic volume index on CMR imaging (7.6 ml/m2, p = 0.033) and echocardiography (9.4 ml/m2, p = 0.008). The change in C-reactive protein levels between admission and 72 hours after admission correlated with the change in the LVESVi (R =+0.71, p = 0.022). In conclusion, in the present pilot study of patients with ST-segment elevation AMI, IL-1 blockade with anakinra was safe and favorably affected by LV remodeling. If confirmed in larger trials, IL-1 blockade might represent a novel therapeutic strategy to prevent heart failure after AMI.
doi:10.1016/j.amjcard.2013.01.287
PMCID: PMC3644511  PMID: 23453459
3.  Comparative Cardiac Toxicity of Anthracyclines In Vitro and In Vivo in the Mouse 
PLoS ONE  2013;8(3):e58421.
Purpose
The antineoplastic efficacy of anthracyclines is limited by their cardiac toxicity. In this study, we evaluated the toxicity of doxorubicin, non-pegylated liposomal-delivered doxorubicin, and epirubicin in HL-1 adult cardiomyocytes in culture as well as in the mouse in vivo.
Methods
The cardiomyocytes were incubated with the three anthracyclines (1 µM) to assess reactive oxygen generation, DNA damage and apoptotic cell death. CF-1 mice (10/group) received doxorubicin, epirubicin or non-pegylated liposomal-doxorubicin (10 mg/kg) and cardiac function was monitored by Doppler echocardiography to measure left ventricular ejection fraction (LVEF), heart rate (HR) and cardiac output (CO) both prior to and 10 days after drug treatment.
Results
In HL-1 cells, non-pegylated liposomal-doxorubicin generated significantly less reactive oxygen species (ROS), as well as less DNA damage and apoptosis activation when compared with doxorubicin and epirubicin. Cultured breast tumor cells showed similar sensitivity to the three anthracyclines. In the healthy mouse, non-pegylated liposomal doxorubicin showed a minimal and non-significant decrease in LVEF with no change in HR or CO, compared to doxorubicin and epirubicin.
Conclusion
This study provides evidence for reduced cardiac toxicity of non-pegylated-liposomal doxorubicin characterized by attenuation of ROS generation, DNA damage and apoptosis in comparison to epirubicin and doxorubicin.
doi:10.1371/journal.pone.0058421
PMCID: PMC3597611  PMID: 23516478
4.  Intracellular Function of Interleukin-1 Receptor Antagonist in Ischemic Cardiomyocytes 
PLoS ONE  2013;8(1):e53265.
Background
Loss of cardiac myocytes due to apoptosis is a relevant feature of ischemic heart disease. It has been described in infarct and peri-infarct regions of the myocardium in coronary syndromes and in ischemia-linked heart remodeling. Previous studies have provided protection against ischemia-induced cardiomyocyte apoptosis by the anti-inflammatory cytokine interleukin-1 receptor-antagonist (IL-1Ra). Mitochondria triggering of caspases plays a central role in ischemia-induced apoptosis. We examined the production of IL-1Ra in the ischemic heart and, based on dual intra/extracellular function of some other interleukins, we hypothesized that IL-1Ra may also directly inhibit mitochondria-activated caspases and cardiomyocyte apoptosis.
Methodology/Principal Findings
Synthesis of IL-1Ra was evidenced in the hearts explanted from patients with ischemic heart disease. In the mouse ischemic heart and in a mouse cardiomyocyte cell line exposed to long-lasting hypoxia, IL-1Ra bound and inhibited mitochondria-activated caspases, whereas inhibition of caspase activation was not observed in the heart of mice lacking IL-1Ra (Il-1ra−/−) or in siRNA to IL-1Ra-interfered cells. An impressive 6-fold increase of hypoxia-induced apoptosis was observed in cells lacking IL-1Ra. IL-1Ra down-regulated cells were not protected against caspase activation and apoptosis by knocking down of the IL-1 receptor, confirming the intracellular, receptor-independent, anti-apoptotic function of IL-1Ra. Notably, the inhibitory effect of IL-1Ra was not influenced by enduring ischemic conditions in which previously described physiologic inhibitors of apoptosis are neutralized.
Conclusions/Significance
These observations point to intracellular IL-1Ra as a critical mechanism of the cell self-protection against ischemia-induced apoptosis and suggest that this cytokine plays an important role in the remodeling of heart by promoting survival of cardiomyocytes in the ischemic regions.
doi:10.1371/journal.pone.0053265
PMCID: PMC3540084  PMID: 23308180
5.  Silencing of hypoxia inducible factor-1α gene attenuated angiotensin II-induced renal injury in Sprague-Dawley rats 
Hypertension  2011;58(4):657-664.
Although it has been shown that up-regulation of hypoxia-inducible factor (HIF)-1α is protective in acute ischemic renal injury, long-term over-activation of HIF-1α is implicated to be injurious in chronic kidney diseases. Angiotensin II (ANG II) is a well-known pathogenic factor producing chronic renal injury and has also been shown to increase HIF-1α. However, the contribution of HIF-1α to ANG II-induced renal injury has not been evidenced. The present study tested the hypothesis that HIF-1α mediates ANG II-induced renal injury in Sprague-Dawley rats. Chronic renal injury was induced by ANG II infusion (200ng/kg/min) for 2 weeks in uninephrectomized rats. Transfection of vectors expressing HIF-1α shRNA into the kidneys knocked down HIF-1α gene expression by 70%, blocked ANG II-induced HIF-1α activation and significantly attenuated ANG II-induced albuminuria, which was accompanied by inhibition of ANG II-induced vascular endothelial growth factor, a known glomerular permeability factor, in glomeruli. HIF-1α shRNA also significantly improved the glomerular morphological damage induced by ANG II. Furthermore, HIF-1α shRNA blocked ANG II-induced upregulation of collagen and α-smooth muscle actin in tubulointerstitial region. There was no difference in creatinine clearance and ANG II-induced increase in blood pressure. HIF-1α shRNA had no effect on ANG II-induced reduction in renal blood flow and hypoxia in the kidneys. These data suggested that over-activation of HIF-1α-mediated gene regulation in the kidney is a pathogenic pathway mediating ANG II-induced chronic renal injuries and normalization of over-activated HIF-1α may be used as a treatment strategy for chronic kidney damages associated with excessive ANG II.
doi:10.1161/HYPERTENSIONAHA.111.177626
PMCID: PMC3174356  PMID: 21896938
glomerular sclerosis; tubulointerstitial; fibrosis; albuminuria; renal blood flow
6.  Enhanced Interleukin-1 Activity Contributes to Exercise Intolerance in Patients with Systolic Heart Failure 
PLoS ONE  2012;7(3):e33438.
Background
Heart failure (HF) is a complex clinical syndrome characterized by impaired cardiac function and poor exercise tolerance. Enhanced inflammation is associated with worsening outcomes in HF patients and may play a direct role in disease progression. Interleukin-1β (IL-1β) is a pro-inflammatory cytokine that becomes chronically elevated in HF and exerts putative negative inotropic effects.
Methods and Results
We developed a model of IL-1β-induced left ventricular (LV) dysfunction in healthy mice that exhibited a 32% reduction in LV fractional shortening (P<0.001) and a 76% reduction in isoproterenol response (P<0.01) at 4 hours following a single dose of IL-1β 3 mcg/kg. This phenotype was reproducible in mice injected with plasma from HF patients and fully preventable by pretreatment with IL-1 receptor antagonist (anakinra). This led to the design and conduct of a pilot clinical to test the effect of anakinra on cardiopulmonary exercise performance in patients with HF and evidence of elevated inflammatory signaling (n = 7). The median peak oxygen consumption (VO2) improved from 12.3 [10.0, 15.2] to 15.1 [13.7, 19.3] mL·kg–1·min–1 (P = 0.016 vs. baseline) and median ventilator efficiency (VE/VCO2 slope) improved from 28.1 [22.8, 31.7] to 24.9 [22.9, 28.3] (P = 0.031 vs. baseline).
Conclusions
These findings suggest that IL-1β activity contributes to poor exercise tolerance in patients with systolic HF and identifies IL-1β blockade as a novel strategy for pharmacologic intervention.
Trial Registration
ClinicalTrials.gov NCT01300650
doi:10.1371/journal.pone.0033438
PMCID: PMC3306393  PMID: 22438931
7.  Altered Oxido-Reductive State in the Diabetic Heart: Loss of Cardioprotection due to Protein Disulfide Isomerase 
Molecular Medicine  2011;17(9-10):1012-1021.
Diabetes is associated with an increased risk of heart failure, in part explained by endoplasmic reticulum stress and apoptosis. Protein disulfide isomerase (PDI) prevents stressed cardiomyocytes apoptosis. We hypothesized that diabetes impairs PDI function by an alteration in its oxido-reductive state. Myocardial biopsies harvested from the anterolateral left ventricular wall from diabetic (n = 7) and nondiabetic (n = 8) patients were used to assess PDI expression and cardiomyocyte death. A mouse model of diabetes (streptozotocin injection, 130 mg/mL) was used to study PDI expression and its redox state after ischemia/reperfusion injury induced by 30-min occlusion of the left anterior coronary artery followed by reperfusion. Transthoracic echocardiography was performed to assess cardiac remodeling after 1 wk. Western blot analysis was used to analyze PDI expression, and methoxy-polyethyleneglycol-maleimide was used to assess its redox state. Dehydroascorbate (DHA) administration was used to restore the PDI redox state. Diabetic patients had a greater number of transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells than nondiabetic patients despite a greater myocardial PDI expression suggesting altered PDI function. Diabetic mice had a worse postinfarction remodeling associated with an altered PDI redox state. DHA treatment restored functional PDI redox state and ameliorated post–myocardial infarction remodeling. An increase in PDI levels with a paradoxical decrease of its active form occurs in the diabetic heart after ischemia and may explain the lack of protective effects of PDI in diabetes. Restoration of PDI redox state prevents adverse remodeling. The potential significance of these findings deserves to be validated in a clinical setting.
doi:10.2119/molmed.2011.00100
PMCID: PMC3188861  PMID: 21637911
8.  Right Ventricular Dysfunction following Acute Myocardial Infarction in the Absence of Pulmonary Hypertension in the Mouse 
PLoS ONE  2011;6(3):e18102.
Background
Cardiac remodelling after AMI is characterized by molecular and cellular mechanisms involving both the ischemic and non-ischemic myocardium. The extent of right ventricular (RV) dilatation and dysfunction and its relation to pulmonary hypertension (PH) following AMI are unknown. The aim of the current study was to evaluate changes in dimensions and function of the RV following acute myocardial infarction (AMI) involving the left ventricle (LV).
Methods
We assessed changes in RV dimensions and function 1 week following experimental AMI involving the LV free wall in 10 mice and assessed for LV and RV dimensions and function and for the presence and degree of PH.
Results
RV fractional area change and tricuspidal annular plane systolic excursion significantly declined by 33% (P = 0.021) and 28% (P = 0.001) respectively. Right ventricular systolic pressure measured invasively in the mouse was within the normal values and unchanged following AMI.
Conclusion
AMI involving the LV and sparing the RV induces a significant acute decline in RV systolic function in the absence of pulmonary hypertension in the mouse indicating that RV dysfunction developed independent of changes in RV afterload.
doi:10.1371/journal.pone.0018102
PMCID: PMC3063789  PMID: 21455304
9.  Carvedilol increases blood pressure response to phenylephrine infusion in heart failure subjects with systolic dysfunction: Evidence of improved vascular α1-adrenoreceptor signal transduction 
American heart journal  2008;156(2):315-321.
INTRODUCTION
α1-AR stimulation produces smooth muscle contraction, vasoconstriction, and myocyte hypertrophy, suggesting a potential therapeutic role for α1-AR antagonists to reduce cardiac workload and myocardial hypertrophy. Preliminary reports suggest that vascular α1-ARs are desensitized in heart failure (HF) in a manner similar to myocardial β1-ARs. We examined α1-AR signal transduction by repeat phenylephrine (PE) infusions in HF patients receiving chronic carvedilol therapy.
METHODS
12 HF subjects not currently receiving β-blockers were up-titrated to maximum tolerable doses of carvedilol. Subjects underwent α1-AR stimulation testing at study baseline, 2-weeks after each dose titration, and 6-months after maintenance of maximum carvedilol dose. PE infusions began at 0.5 mcg/kg/min, with dose titrations every 10 minutes, to a maximum of 5 mcg/kg/min. PE dose response was evaluated by the PE rate required to elicit a 20 mmHg increase in systolic BP, designated PS20.
RESULTS
All doses of carvedilol significantly reduced pre-infusion measures of heart rate, systolic BP, diastolic BP, and mean arterial pressure. However, carvedilol also produced a paradoxical trend towards PS20 reduction (indicating increased PE response) that reached significance at the completion of carvedilol dose titration (PS20 ratio vs baseline = 0.78, p<0.001). All effects were maintained over a 6-month treatment period with no evidence of tolerance.
CONCLUSIONS
Increasing BP response to PE infusion suggests improvement in vascular α1-AR signal transduction with chronic carvedilol therapy. This effect is evident despite no detectable tolerance to pre-infusion BP reductions. The varying affinities of α1-AR subtypes for carvedilol and PE may have contributed to this finding.
doi:10.1016/j.ahj.2008.04.004
PMCID: PMC2577898  PMID: 18657662
alpha-blocker; carvedilol; phenylephrine; chronic heart failure
10.  Benefits of β blockers in patients with heart failure and reduced ejection fraction: network meta-analysis 
Objective To clarify whether any particular β blocker is superior in patients with heart failure and reduced ejection fraction or whether the benefits of these agents are mainly due to a class effect.
Design Systematic review and network meta-analysis of efficacy of different β blockers in heart failure.
Data sources CINAHL(1982-2011), Cochrane Collaboration Central Register of Controlled Trials (-2011), Embase (1980-2011), Medline/PubMed (1966-2011), and Web of Science (1965-2011).
Study selection Randomized trials comparing β blockers with other β blockers or other treatments.
Data extraction The primary endpoint was all cause death at the longest available follow-up, assessed with odds ratios and Bayesian random effect 95% credible intervals, with independent extraction by observers.
Results 21 trials were included, focusing on atenolol, bisoprolol, bucindolol, carvedilol, metoprolol, and nebivolol. As expected, in the overall analysis, β blockers provided credible mortality benefits in comparison with placebo or standard treatment after a median of 12 months (odds ratio 0.69, 0.56 to 0.80). However, no obvious differences were found when comparing the different β blockers head to head for the risk of death, sudden cardiac death, death due to pump failure, or drug discontinuation. Accordingly, improvements in left ventricular ejection fraction were also similar irrespective of the individual study drug.
Conclusion The benefits of β blockers in patients with heart failure with reduced ejection fraction seem to be mainly due to a class effect, as no statistical evidence from current trials supports the superiority of any single agent over the others.
doi:10.1136/bmj.f55
PMCID: PMC3546627  PMID: 23325883
11.  Socioeconomic Status, Functional Recovery, and Long-Term Mortality among Patients Surviving Acute Myocardial Infarction 
PLoS ONE  2013;8(6):e65130.
Objectives
To examine the relationship between socio-economic status (SES), functional recovery and long-term mortality following acute myocardial infarction (AMI).
Background
The extent to which SES mortality disparities are explained by differences in functional recovery following AMI is unclear.
Methods
We prospectively examined 1368 patients who survived at least one-year following an index AMI between 1999 and 2003 in Ontario, Canada. Each patient was linked to administrative data and followed over 9.6 years to track mortality. All patients underwent medical chart abstraction and telephone interviews following AMI to identify individual-level SES, clinical factors, processes of care (i.e., use of, and adherence, to evidence-based medications, physician visits, invasive cardiac procedures, referrals to cardiac rehabilitation), as well as changes in psychosocial stressors, quality of life, and self-reported functional capacity.
Results
As compared with their lower SES counterparts, higher SES patients experienced greater functional recovery (1.80 ml/kg/min average increase in peak V02, P<0.001) after adjusting for all baseline clinical factors. Post-AMI functional recovery was the strongest modifiable predictor of long-term mortality (Adjusted HR for each ml/kg/min increase in functional capacity: 0.91; 95% CI: 0.87–0.94, P<0.001) irrespective of SES (P = 0.51 for interaction between SES, functional recovery, and mortality). SES-mortality associations were attenuated by 27% after adjustments for functional recovery, rendering the residual SES-mortality association no longer statistically significant (Adjusted HR: 0.84; 95% CI:0.70–1.00, P = 0.05). The effects of functional recovery on SES-mortality associations were not explained by access inequities to physician specialists or cardiac rehabilitation.
Conclusions
Functional recovery may play an important role in explaining SES-mortality gradients following AMI.
doi:10.1371/journal.pone.0065130
PMCID: PMC3670842  PMID: 23755180
12.  Effects of Pharmacists' Interventions on Appropriateness of Prescribing and Evaluation of the Instruments' (MAI, STOPP and STARTs') Ability to Predict Hospitalization–Analyses from a Randomized Controlled Trial 
PLoS ONE  2013;8(5):e62401.
Background
Appropriateness of prescribing can be assessed by various measures and screening instruments. The aims of this study were to investigate the effects of pharmacists' interventions on appropriateness of prescribing in elderly patients, and to explore the relationship between these results and hospital care utilization during a 12-month follow-up period.
Methods
The study population from a previous randomized controlled study, in which the effects of a comprehensive pharmacist intervention on re-hospitalization was investigated, was used. The criteria from the instruments MAI, STOPP and START were applied retrospectively to the 368 study patients (intervention group (I) n = 182, control group (C) n = 186). The assessments were done on admission and at discharge to detect differences over time and between the groups. Hospital care consumption was recorded and the association between scores for appropriateness, and hospitalization was analysed.
Results
The number of Potentially Inappropriate Medicines (PIMs) per patient as identified by STOPP was reduced for I but not for C (1.42 to 0.93 vs. 1.46 to 1.66 respectively, p<0.01). The number of Potential Prescription Omissions (PPOs) per patient as identified by START was reduced for I but not for C (0.36 to 0.09 vs. 0.42 to 0.45 respectively, p<0.001). The summated score for MAI was reduced for I but not for C (8.5 to 5.0 and 8.7 to 10.0 respectively, p<0.001). There was a positive association between scores for MAI and STOPP and drug-related readmissions (RR 8–9% and 30–34% respectively). No association was detected between the scores of the tools and total re-visits to hospital.
Conclusion
The interventions significantly improved the appropriateness of prescribing for patients in the intervention group as evaluated by the instruments MAI, STOPP and START. High scores in MAI and STOPP were associated with a higher number of drug-related readmissions.
doi:10.1371/journal.pone.0062401
PMCID: PMC3656885  PMID: 23690938
13.  BVT.2733, a Selective 11β-Hydroxysteroid Dehydrogenase Type 1 Inhibitor, Attenuates Obesity and Inflammation in Diet-Induced Obese Mice 
PLoS ONE  2012;7(7):e40056.
Background
Inhibition of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) is being pursued as a new therapeutic approach for the treatment of obesity and metabolic syndrome. Therefore, there is an urgent need to determine the effect of 11β-HSD1 inhibitor, which suppresses glucocorticoid action, on adipose tissue inflammation. The purpose of the present study was to examine the effect of BVT.2733, a selective 11β-HSD1 inhibitor, on expression of pro-inflammatory mediators and macrophage infiltration in adipose tissue in C57BL/6J mice.
Methodology/Principal Findings
C57BL/6J mice were fed with a normal chow diet (NC) or high fat diet (HFD). HFD treated mice were then administrated with BVT.2733 (HFD+BVT) or vehicle (HFD) for four weeks. Mice receiving BVT.2733 treatment exhibited decreased body weight and enhanced glucose tolerance and insulin sensitivity compared to control mice. BVT.2733 also down-regulated the expression of inflammation-related genes including monocyte chemoattractant protein 1 (MCP-1), tumor necrosis factor alpha (TNF-α) and the number of infiltrated macrophages within the adipose tissue in vivo. Pharmacological inhibition of 11β-HSD1 and RNA interference against 11β-HSD1 reduced the mRNA levels of MCP-1 and interleukin-6 (IL-6) in cultured J774A.1 macrophages and 3T3-L1 preadipocyte in vitro.
Conclusions/Significance
These results suggest that BVT.2733 treatment could not only decrease body weight and improve metabolic homeostasis, but also suppress the inflammation of adipose tissue in diet-induced obese mice. 11β-HSD1 may be a very promising therapeutic target for obesity and associated disease.
doi:10.1371/journal.pone.0040056
PMCID: PMC3388048  PMID: 22768329
14.  Alterations in the Interleukin-1/Interleukin-1 Receptor Antagonist Balance Modulate Cardiac Remodeling following Myocardial Infarction in the Mouse 
PLoS ONE  2011;6(11):e27923.
Background
Healing after acute myocardial infarction (AMI) is characterized by an intense inflammatory response and increased Interleukin-1 (IL-1) tissue activity. Genetically engineered mice lacking the IL-1 receptor (IL-1R1-/-, not responsive to IL-1) or the IL-1 receptor antagonist (IL-1Ra, enhanced response to IL-1) have an altered IL-1/IL-1Ra balance that we hypothesize modulates infarct healing and cardiac remodeling after AMI.
Methods
IL-1R1-/- and IL-1Ra-/- male mice and their correspondent wild-types (WT) were subjected to permanent coronary artery ligation or sham surgery. Infarct size (trichrome scar size), apoptotic cell death (TUNEL) and left ventricular (LV) dimensions and function (echocardiography) were measured prior to and 7 days after surgery.
Results
When compared with the corresponding WT, IL-1R1-/- mice had significantly smaller infarcts (−25%), less cardiomyocyte apoptosis (−50%), and reduced LV enlargement (LV end-diastolic diameter increase [LVEDD], −20%) and dysfunction (LV ejection fraction [LVEF] decrease, −50%), whereas IL-1Ra-/- mice had significantly larger infarcts (+75%), more apoptosis (5-fold increase), and more severe LV enlargement (LVEDD increase,+30%) and dysfunction (LVEF decrease, +70%)(all P values <0.05).
Conclusions
An imbalance in IL-1/IL-1Ra signaling at the IL-1R1 level modulates the severity of cardiac remodeling after AMI in the mouse, with reduced IL-1R1 signaling providing protection and unopposed IL-1R1 signaling providing harm.
doi:10.1371/journal.pone.0027923
PMCID: PMC3225370  PMID: 22140485

Results 1-14 (14)