Ezh2 emerges as an epigenetic checkpoint regulator during monocyte differentiation limiting cardiac dysfunction post-MI

Epigenetic regulation of histone H3K27 methylation has recently emerged as a key step during alternative immunoregulatory M2-like macrophage polarization; known to impact cardiac repair after Myocardial Infarction (MI). We hypothesized that EZH2, responsible for H3K27 methylation, could act as an epigenetic checkpoint regulator during this process. We demonstrate for the first time an ectopic EZH2, and putative, cytoplasmic inactive localization of the epigenetic enzyme, during monocyte differentiation into M2 macrophages in vitro as well as in immunomodulatory cardiac macrophages in vivo in the post-MI acute inflammatory phase. Moreover, we show that pharmacological EZH2 inhibition, with GSK-343, resolves H3K27 methylation of bivalent gene promoters, thus enhancing their expression to promote human monocyte repair functions. In line with this protective effect, GSK-343 treatment accelerated cardiac inflammatory resolution preventing infarct expansion and subsequent cardiac dysfunction in female mice post-MI in vivo. In conclusion, our study reveals that pharmacological epigenetic modulation of cardiac-infiltrating immune cells may hold promise to limit adverse cardiac remodeling after MI.

Knowledge exchange between patient and pharmacist: A mixed methods study to explore the role of pharmacists in patient education and counseling in asthma and pulmonary arterial hypertension

OBJECTIVES

To better understand the role of pharmacists in patient education and counselling: describe the perception of knowledge exchange (KE) between asthma/pulmonary arterial hypertension patients and pharmacists (hospital/community) according to four dimensions (4C-typology): cure (C1), care (C2); coordination/supply chain (C3), characteristics of the pathophysiology/disease mechanisms (C4); factors correlated with KE.

METHODS

A mixed methods approach was used. Part A: data from semi-structured patient interviews were processed (thematic analysis), and a questionnaire developed. Part B: completed patient questionnaires were processed by correspondence factor analysis.

RESULTS

KE (4C-typology) was correlated with pathology, disease severity, disease duration, age, hospital/community pharmacist. Patients expected pharmacists to provide C2/C3 services. KE with pharmacists covered C1/C2/C3, and with physicians, C1/C2/C4. While patients perceived KE as a means of self-learning to improve self-care skills, the two-way nature meant it provided specific experiential information feedback to pharmacists.

CONCLUSIONS

This 4C-typology provides a holistic framework for optimising the pharmacists' role in education and counselling of patients with chronic diseases.

A Supraceliac Aortic Cross Clamping Model to Explore Remote Lung Injury and the Endothelial Glycocalyx

BACKGROUND

We hypothesized that supraceliac aortic cross clamping could induce lung injury mediated by an inflammatory ischemia-reperfusion (IR) trigger. We aimed to characterize glycocalyx (GCX), a component of endothelial membrane, participating to remote lung injury.

METHODS

Rats underwent supraceliac aortic cross clamping for 40 min and were sacrificed at 0, 3, 6, and 24 hr of reperfusion (n = 10/group). Each group was compared to sham (n = 6/group). GCX products (syndecan-1 [Sdc-1] and heparan sulfate [HS]), tumor necrosis factor-alpha (TNF-α), and interleukin-1β (IL-1β) were measured in plasma (enzyme-linked immunosorbent assay[ELISA]). Lungs were harvested for measurements of TNF-α, IL-1β (polymerase chain reaction) and Sdc-1 (western blotting [WB]). Histologic lung injury scoring and pulmonary gravimetry were analyzed in a blinded manner.

RESULTS

Plasmatic Sdc-1, HS, TNF-α, and IL-1β reached peak levels at 3 hr. Levels were significantly higher in clamping groups than sham at 6 hr for Sdc-1, at 0 and 3 hr for HS, at 3 and 6 hr for TNF-α, and at 3 hr for IL-1β. Lung TNF-α and Interleukin-1β reached peak levels at 6 hr. Levels were significantly higher than sham at 6 and 24 hr for TNF-α and at 6 hr for IL-1β. Lung Sdc-1 was lowest at 3 hr. Sdc-1 was not significantly different compared to sham at the different reperfusion times. At 3 hr, it was 0.27 ± 0.03 vs. 0.33 ± 0.02 (sham) (P = 0.09). Histopathologic scores at 6 and 24 hr were higher in clamping groups than sham. At 6 and 24 hr, it was higher for hemorrhage, polynuclear neutrophil (PNN) infiltration and intravascular leukocytes. Pulmonary edema was higher by gravimetry at 0 and 6 hr.

CONCLUSIONS

Supra celiac aortic clamping causes early lung injury in relation with a systemic inflammatory response associated with altered GCX structure.

Endothelium-Specific Deficiency of Polycystin-1 Promotes Hypertension and Cardiovascular Disorders

Background:

Autosomal dominant polycystic kidney disease is the most frequent hereditary kidney disease and is generally due to mutations in PKD1 and PKD2 , encoding polycystins 1 and 2. In autosomal dominant polycystic kidney disease, hypertension and cardiovascular disorders are highly prevalent, but their mechanisms are partially understood.

Methods:

Since endothelial cells express the polycystin complex, where it plays a central role in the mechanotransduction of blood flow, we generated a murine model with inducible deletion of Pkd1 in endothelial cells ( Cdh5-Cre ERT2 ; Pkd1 fl/fl ) to specifically determine the role of endothelial polycystin-1 in autosomal dominant polycystic kidney disease.

Results:

Endothelial deletion of Pkd1 induced endothelial dysfunction, as demonstrated by impaired flow-mediated dilatation of resistance arteries and impaired relaxation to acetylcholine, increased blood pressure and prevented the normal development of arteriovenous fistula. In experimental chronic kidney disease induced by subtotal nephrectomy, endothelial deletion of Pkd1 further aggravated endothelial dysfunction, vascular remodeling, and heart hypertrophy.

Conclusions:

Altogether, this study provides the first in vivo demonstration that specific deletion of Pkd1 in endothelial cells promotes endothelial dysfunction and hypertension, impairs arteriovenous fistula development, and potentiates the cardiovascular alterations associated with chronic kidney disease.

Soluble RAGE as a Prognostic Marker of Worsening in Patients Admitted to the ICU for COVID-19 Pneumonia: A Prospective Cohort Study

Background: The different waves of SARS-CoV-2 infection have strained hospital resources and, notably, intensive care units (ICUs). Identifying patients at risk of developing a critical condition is essential to correctly refer patients to the appropriate structure and to spare limited resources. The soluble form of RAGE (sRAGE), the endoplasmic stress response and its surrogates, GRP78 and VEGF-A, may be interesting markers. Methods: This was a prospective monocenter cohort study of adult patients admitted to the ICU for severe COVID-19 pneumonia. The plasma levels of sRAGE, GRP78 and VEGF-A were measured within the first 24 h. Patients were classified as critical if they further needed vasopressor therapy, renal replacement therapy, or invasive mechanical ventilation, or died during their ICU stay, and were otherwise classified as not critical. Results: A total of 98 patients were included and 39 developed a critical condition. Critical patients presented higher sRAGE (626 [450−1043] vs. 227 [137−404] pg/mL, p < 0.0001), interleukin-6 (43 [15−112] vs. 11 [5−20] pg/mL, p < 0.0001), troponin T (17 [9−39] vs. 10 [6−18] pg/mL, p = 0.003) and NT-pro-BNP (321 [118−446] vs. 169 [63−366] pg/mL, p = 0.009) plasma levels. No difference was observed for VEGF-A and GRP78. The variables independently associated with worsening in the ICU were sRAGE (1.03 [1.01−1.05] per 10 pg/mL) and age (1.7 [1.2−2.4] per 5 years). An sRAGE value of 449.5 pg/mL predicted worsening with a sensitivity of 77% and a specificity of 80%. Conclusion: sRAGE may allow the identification of patients at risk of developing a critical form of COVID-19 pneumonia, and thus may be useful to correctly refer patients to the appropriate structure of care.

Regulation and impact of cardiac lymphangiogenesis in pressure-overload-induced heart failure

AIMS

Lymphatics are essential for cardiac health, and insufficient lymphatic expansion (lymphangiogenesis) contributes to development of heart failure (HF) after myocardial infarction. However, the regulation and impact of lymphangiogenesis in non-ischemic cardiomyopathy following pressure-overload remains to be determined. Here, we investigated cardiac lymphangiogenesis following transversal aortic constriction (TAC) in C57Bl/6 and Balb/c mice, and in end-stage HF patients.

METHODS & RESULTS

Cardiac function was evaluated by echocardiography, and cardiac hypertrophy, lymphatics, inflammation, edema, and fibrosis by immunohistochemistry, flow cytometry, microgravimetry, and gene expression analysis. Treatment with neutralizing anti-VEGFR3 antibodies was applied to inhibit cardiac lymphangiogenesis in mice.We found that VEGFR3-signaling was essential to prevent cardiac lymphatic rarefaction after TAC in C57Bl/6 mice. While anti-VEGFR3-induced lymphatic rarefaction did not significantly aggravate myocardial edema post-TAC, cardiac immune cell levels were increased, notably myeloid cells at 3 weeks and T lymphocytes at 8 weeks. Moreover, whereas inhibition of lymphangiogenesis did not aggravate interstitial fibrosis, it increased perivascular fibrosis and accelerated development of left ventricular (LV) dilation and dysfunction. In clinical HF samples, cardiac lymphatic density tended to increased, although lymphatic sizes decreased, notably in patients with dilated cardiomyopathy. Similarly, comparing C57Bl/6 and Balb/c mice, lymphatic remodeling post-TAC was linked to LV dilation rather than to hypertrophy. The striking lymphangiogenesis in Balb/c was associated with reduced cardiac levels of macrophages, B cells, and perivascular fibrosis at 8 weeks post-TAC, as compared with C57Bl/6 mice that displayed weak lymphangiogenesis. Surprisingly, however, it did not suffice to resolve myocardial edema, nor prevent HF development.

CRISPR/Cas9-mediated inactivation of the phosphatase activity of soluble epoxide hydrolase prevents obesity and cardiac ischemic injury

INTRODUCTION

Although the physiological role of the C-terminal hydrolase domain of the soluble epoxide hydrolase (sEH-H) is well investigated, the function of its N-terminal phosphatase activity (sEH-P) remains unknown.

OBJECTIVES

This study aimed to assess in vivo the physiological role of sEH-P.

METHODS

CRISPR/Cas9 was used to generate a novel knock-in (KI) rat line lacking the sEH-P activity.

RESULTS

The sEH-P KI rats has a decreased metabolism of lysophosphatidic acids to monoacyglycerols. KI rats grew almost normally but with less weight and fat mass gain while insulin sensitivity was increased compared to wild-type rats. This lean phenotype was more marked in males than in female KI rats and mainly due to decreased food consumption and enhanced energy expenditure. In fact, sEH-P KI rats had an increased lipolysis allowing to supply fatty acids as fuel to potentiate brown adipose thermogenesis under resting condition and upon cold exposure. The potentiation of thermogenesis was abolished when blocking PPARγ, a nuclear receptor activated by intracellular lysophosphatidic acids, but also when inhibiting simultaneously sEH-H, showing a functional interaction between the two domains. Furthermore, sEH-P KI rats fed a high-fat diet did not gain as much weight as the wild-type rats, did not have increased fat mass and did not develop insulin resistance or hepatic steatosis. In addition, sEH-P KI rats exhibited enhanced basal cardiac mitochondrial activity associated with an enhanced left ventricular contractility and were protected against cardiac ischemia-reperfusion injury.

CONCLUSION

Our study reveals that sEH-P is a key player in energy and fat metabolism and contributes together with sEH-H to the regulation of cardiometabolic homeostasis. The development of pharmacological inhibitors of sEH-P appears of crucial importance to evaluate the interest of this promising therapeutic strategy in the management of obesity and cardiac ischemic complications.

Cardiopulmonary bypass increases endothelial dysfunction after pulmonary ischaemia-reperfusion in an animal model

OBJECTIVES

Endothelial dysfunction during ischaemia-reperfusion (IR) is a major cause of primary graft dysfunction during lung transplantation. The routine use of cardiopulmonary bypass (CPB) during lung transplantation remains controversial. However, the contribution of CPB to pulmonary endothelial dysfunction remains unclear. The objective was to investigate the impact of CPB on endothelial dysfunction in a lung IR rat model.

METHODS

Rats were allocated to 4 groups: (i) Sham, (ii) IR, (iii) CPB and (iv) IR-CPB. The primary outcome was the study of pulmonary vascular reactivity by wire myograph. We also assessed glycocalyx degradation by enzyme-linked immunosorbent assay and electron microscopy and both systemic and pulmonary inflammation by enzyme-linked immunosorbent assay and immunohistochemistry. Rats were exposed to 45 min of CPB and IR. We used a CPB model allowing femoro-femoral support with left pulmonary hilum ischaemia for IR.

RESULTS

Pulmonary endothelium-dependent relaxation to acetylcholine was markedly reduced in the IR-CPB group (10.7 ± 9.1%) compared to the IR group (50.5 ± 5.2%, P < 0.001), the CPB group (54.1 ± 4.7%, P < 0.001) and the sham group (80.8 ± 6.7%, P < 0.001), suggesting that the association of pulmonary IR and CPB increases endothelial dysfunction. In IR-CPB, IR and CPB groups, vasorelaxation was completely abolished when inhibiting nitric oxide synthase, suggesting that this relaxation process was mainly mediated by nitric oxide. We observed higher syndecan-1 plasma levels in the IR-CPB group in comparison with the other groups, reflecting an increased degradation of glycocalyx. We also observed higher systemic inflammation in the IR-CPB group as shown by the increased plasma levels of IL-1β, IL-10.

CONCLUSIONS

CPB significantly increased the IR-mediated effects on pulmonary endothelial dysfunction. Therefore, the use of CPB during lung transplantation could be deleterious, by increasing endothelial dysfunction.

Transient heart rate reduction improves acute decompensated heart failure-induced left ventricular and coronary dysfunction

Aims

Acute decompensated heart failure (ADHF), a live‐threatening complication of heart failure (HF), associates a further decrease of the already by HF‐impaired cardiac function with an increase in heart rate. We evaluated, using a new model of ADHF, whether heart rate reduction (HRR) opposes the acute decompensation‐related aggravation of cardiovascular dysfunction.

Methods and results

Cardiac output (echocardiography), cardiac tissue perfusion (magnetic resonance imaging), pulmonary wet weight, and in vitro coronary artery relaxation (Mulvany) were assessed 1 and 14 days after acute decompensation induced by salt‐loading (1.8 g/kg, PO) in rats with well‐established HF due to coronary ligation. HRR was induced by administration of the I_f current inhibitor S38844, 12 mg/kg PO twice daily for 2.5 days initiated 12 h or 6 days after salt‐loading (early or delayed treatment, respectively). After 24 h, salt‐loading resulted in acute decompensation, characterized by a reduction in cardiac output (HF: 130 ± 5 mL/min, ADHF: 105 ±  8 mL/min; P < 0.01), associated with a decreased myocardial perfusion (HF: 6.41 ± 0.53 mL/min/g, ADHF: 4.20 ± 0.11 mL/min/g; P < 0.01), a slight increase in pulmonary weight (HF: 1.68 ± 0.09 g, ADHF: 1.81 ± 0.15 g), and impaired coronary relaxation (HF: 55 ± 1% of pre‐contraction at acetylcholine 4.5 10⁻⁵ M, ADHF: 27 ± 7 %; P < 0.01). Fourteen days after salt‐loading, cardiac output only partially recovered (117 ± 5 mL/min; P < 0.05), while myocardial tissue perfusion (4.51 ± 0.44 mL/min; P < 0.01) and coronary relaxation (28 ± 4%; P < 0.01) remained impaired, but pulmonary weight further increased (2.06 ± 0.15 g, P < 0.05). Compared with untreated ADHF, HRR induced by S38844 improved cardiac output (125 ± 1 mL/min; P < 0.05), myocardial tissue perfusion (6.46 ± 0.42 mL/min/g; P < 0.01), and coronary relaxation (79 ± 2%; P < 0.01) as soon as 12 h after S38844 administration. These effects persisted beyond S38844 administration, illustrated by the improvements in cardiac output (130 ± 6 mL/min; P < 0.05), myocardial tissue perfusion (6.38 ± 0.48 mL/min/g; P < 0.01), and coronary relaxation (71 ± 4%; P < 0.01) at Day 14. S38844 did not modify pulmonary weight at Day 1 (1.78 ± 0.04 g) but tended to decrease pulmonary weight at Day 14 (1.80 ± 0.18 g). While delayed HRR induced by S38844 never improved cardiac function, early HRR rendered less prone to a second acute decompensation.

Conclusions

In a model mimicking human ADHF, early, but not delayed, transient HRR induced by the I_f current inhibitor S38844 opposes acute decompensation by preventing the decompensated‐related aggravation of cardiovascular dysfunction as well as the development of pulmonary congestion, and these protective effects persist beyond the transient treatment. Whether early transient HRR induced by I_f current inhibitors or other bradycardic agents, i.e. beta‐blockers, exerts beneficial effects in human ADHF warrants further investigation.

[IMPACTCHIMIO: Development and multicentric validation of a tool for collecting pharmaceutical interventions carried out within chemotherapy reconstitution units]

OBJECTIVES

To develop and validate prospectively a specific tool for pharmaceutical interventions performed in centralized cytotoxic preparation units.

METHODS

A pharmaceutical intervention is defined as a type of intervention performed in relation to a problem encountered. ImpactChimio is derived from the Act-IP® (SFPC) tool. The initial version (version 1) was developed from the pharmaceutical interventions collected over 1 year by the pilot centre. Its validation was carried out by the Delphi method via a prospective multicentric collection to assess its robustness (real life pharmaceutical interventions) and reproducibility (50 pharmaceutical interventions classified by pharmacists naive or not to the tool and study of classification divergences).

RESULTS

The development of the tool (version 1) was based on the analysis of 412 pharmaceutical interventions. For its validation, 196 pharmaceutical interventions were provided by 6 centers for 5 months. The changes have been incorporated into the new versions of the tool (version 2 and version 3). Six naive and six non-naive pharmacists then tested reproducibility by reclassifying 50 selected pharmaceutical interventions into version 3. A total of 136 discrepancies (11.3 %) were found out of 1200 responses: 66 related to the problem encountered and 70 to the type of intervention. No statistically significant differences were found between naive and non-naive pharmacists.

CONCLUSIONS

ImpactChimio is the first pharmaceutical interventions' specific tool for centralized cytotoxic preparation units, developed and validated by a multicentric study using the Delphi method. It makes possible to enhance the value of the analysis activity and to identify training areas for the teams.

Short-and long-term administration of imeglimin counters cardiorenal dysfunction in a rat model of metabolic syndrome

INTRODUCTION

Imeglimin, a glucose-lowering agent targeting mitochondrial bioenergetics, decreases reactive oxygen species (ROS) overproduction and improves glucose homeostasis. We investigated whether this is associated with protective effects on metabolic syndrome-related left ventricular (LV) and vascular dysfunctions.

METHODS

We used Zucker fa/fa rats to assess the effects on LV function, LV tissue perfusion, LV oxidative stress and vascular function induced by imeglimin administered orally for 9 or 90 days at a dose of 150 mg/kg twice daily.

RESULTS

Compared to untreated animals, 9- and 90-day imeglimin treatment decreased LV end-diastolic pressure and LV end-diastolic pressure-volume relation, increased LV tissue perfusion and decreased LV ROS production. Simultaneously, imeglimin restored acetylcholine-mediated coronary relaxation and mesenteric flow-mediated dilation. One hour after imeglimin administration, when glucose plasma levels were not yet modified, imeglimin reduced LV mitochondrial ROS production and improved LV function. Ninety-day imeglimin treatment reduced related LV and kidney fibrosis and improved kidney function.

CONCLUSION

In a rat model, mimicking Human metabolic syndrome, imeglimin immediately countered metabolic syndrome-related cardiac diastolic and vascular dysfunction by reducing oxidative stress/increased NO bioavailability and improving myocardial perfusion and after 90-day treatment myocardial and kidney structure, effects that are, at least in part, independent from glucose control.

Risk evaluation of the use of complementary and alternative medicines in cancer

INTRODUCTION

Cancer patients use complementary and alternative medicines (CAM) to improve their well-being. Little is known about real risks.

OBJECTIVE

To highlight 3 different types of axes: 1/cancer patients' perceptions concerning CAM; 2/misinformation/miscommunication about CAM; 3/CAM toxicity (direct toxicity, CAM-anticancer drugs, CAM-cancer interactions).

METHOD

A questionnaire was proposed to cancer patients for 2 months. The CAM toxicity was analyzed if patients documented their drugs and CAM.

RESULTS

Eighty-five patients responded: 72/85 were taking≥1CAM. In total, 95% patients were satisfied. There was an increasing CAM intake after cancer diagnosis. One hundred and seventeen different CAM were identified (63 herbs, 24 essential oils, 28 food supplements, 2 homeopathic specialities). Only 30/85 were aware CAM could interact with anticancer drugs. No other type of risk was perceived.

INFORMATION SOURCES

43/85 Internet, 38/85 general practitioner, 38/85 community pharmacist, 32/85 entourage, 25/85 other patients, 22/85 oncologist. In total, 81.3% questioned healthcare professionals (HCP) about CAM. Twelve patients noticed HCP lacked knowledge regarding CAM. The toxicity analysis was carried out for 24 patients who consumed 1 to 24CAM. In total, 133CAM were reported, including 87 different CAM. For only 43CAM/87, studies were found. All patients presented≥1risk: 14 at risk of CAM-cancer interactions, 15 of CAM-anticancer drug interactions, 21 of CAM direct toxicities.

CONCLUSION

Many CAM are used by patients. The diagnosis of cancer favors their use. The risks are manifold: low perception of risk that can be induced by CAM, diverse and insecure sources of information and many potential toxicities that are not scientifically documented.

Lymphatic and Immune Cell Cross-Talk Regulates Cardiac Recovery After Experimental Myocardial Infarction

Supplemental Digital Content is available in the text.

Objective:

Lymphatics play an essential pathophysiological role in promoting fluid and immune cell tissue clearance. Conversely, immune cells may influence lymphatic function and remodeling. Recently, cardiac lymphangiogenesis has been proposed as a therapeutic target to prevent heart failure after myocardial infarction (MI). We investigated the effects of gene therapy to modulate cardiac lymphangiogenesis post-MI in rodents. Second, we determined the impact of cardiac-infiltrating T cells on lymphatic remodeling in the heart.

Approach and Results:

Comparing adenoviral versus adeno-associated viral gene delivery in mice, we found that only sustained VEGF (vascular endothelial growth factor)-C_C156S therapy, achieved by adeno-associated viral vectors, increased cardiac lymphangiogenesis, and led to reduced cardiac inflammation and dysfunction by 3 weeks post-MI. Conversely, inhibition of VEGF-C/-D signaling, through adeno-associated viral delivery of soluble VEGFR3 (vascular endothelial growth factor receptor 3), limited infarct lymphangiogenesis. Unexpectedly, this treatment improved cardiac function post-MI in both mice and rats, linked to reduced infarct thinning due to acute suppression of T-cell infiltration. Finally, using pharmacological, genetic, and antibody-mediated prevention of cardiac T-cell recruitment in mice, we discovered that both CD4⁺ and CD8⁺ T cells potently suppress, in part through interferon-γ, cardiac lymphangiogenesis post-MI.

Conclusions:

We show that resolution of cardiac inflammation after MI may be accelerated by therapeutic lymphangiogenesis based on adeno-associated viral gene delivery of VEGF-C_C156S. Conversely, our work uncovers a major negative role of cardiac-recruited T cells on lymphatic remodeling. Our results give new insight into the interconnection between immune cells and lymphatics in orchestration of cardiac repair after injury.

Evaluation of a program of pharmaceutical counseling for French patients on oral anticoagulant therapy

Background Oral anticoagulants are widely used for treatment and prevention of thromboembolic diseases. We set up a pharmaceutical counseling program for both direct oral anticoagulant and vitamin K antagonist drugs in our hospital in 2015. Objective Evaluate patient satisfaction and the evolution of their knowledge throughout the pharmaceutical counseling program on anticoagulants and identify knowledge variability factors. Setting Cardiology Inpatient Unit from the University Antoine Béclère Hospital, France. Methods Evaluation was based on data collection of patients surveyed between 2015 and 2018. Inpatients in the cardiology department on oral anticoagulants were eligible. The learning process was designed to enhance patient knowledge and understanding based on 10 cognitive or self-management skills, relating to the optimization of oral anticoagulant therapy management. It consisted in 2 face-to-face interviews during hospitalization and 2 additional phone interviews one and six months after discharge. The median patient score was evaluated at each step of the process as well as the mean score for each item from the global population. A sub-analysis was run on the less well-acquired skills in order to identify risk factors for limited knowledge. The association between those factors and the level of knowledge (score ≥ 7 or < 7) was assessed using Chi square test followed by multivariate analysis. Main outcome measure Patient knowledge of anticoagulation therapy depending on specific factors. Results Of the 880 patients eligible for pharmaceutical counseling, 319 entered the process and 102 completed it. Median knowledge scores were 8/10 and 9/10 after the first and the final interviews respectively with a significant improvement (p = 0.0003). The least well-acquired items at each step were surveillance and under-dosing management. The sub-analysis showed the use of vitamin K antagonist to be linked to an enhanced understanding related to treatment surveillance (p = 0.029). Patients suffering from atrial fibrillation were found to have a worse understanding of under-dosing management (p = 0.013). Finally, patients evaluated the process as helpful and suitable for their conditions. Conclusion Pharmaceutical counseling is appropriate for patients, improving and maintaining knowledge of oral anticoagulants. Our evaluation highlights the need to focus on patient-specific profiles to reach a satisfactory level of knowledge.

Gene Expression of Protein Tyrosine Phosphatase 1B and Endoplasmic Reticulum Stress During Septic Shock

Introduction: Protein Tyrosine Phosphatase 1B (PTP1B) and endoplasmic reticulum stress (ERS) are involved in the septic inflammatory response. Their inhibition is associated with improved survival in murine models of sepsis. The objective was to describe PTP1B and ERS expression during septic shock in human.

Material and Methods: Prospective study including patients admitted to intensive care unit (ICU) for septic shock. Blood samples were collected on days 1 (D1), 3 and 5 (D5). Quantitative PCR (performed from whole blood) evaluated the expression of genes coding for PTP1B (PTPN1) and key elements of ERS (GRP78, ATF6, CHOP) or for endothelial dysfunction-related markers (ICAM1 and ET1). We analyzed gene variation between D5 and D1, collected glycemic parameters, insulin resistance and organ failure was evaluated by Sequential Organ Failure Assessment (SOFA) score.

Results: We included 44 patients with a mean SAPS II 50 ± 16 and a mortality rate of 13.6%. Between D1 and D5, there was a significant decrease of PTPN1 (p < 0.001) and ATF6 (p < 0.001) expressions. Their variations of expression were correlated with SOFA variation (PTPN1, r = 0.35, CI 95% [0.05; 0.54], p = 0.03 and ATF6, r = 0.45 CI 95% [0.20; 0.65], p < 0.001). We did not find any correlation between PTPN1 expression and insulin resistance or glycemic parameters. Between D1 and D5, ATF6 and PTPN1 expressions were correlated with that of ET1.

Conclusions: Our study has evaluated for the first time the expression of PTP1B and ERS in patients with septic shock, revealing that gene expression variation of PTPN1 and ATF6 are partly correlated with the evolution of septic organ failure and with endothelial dysfunction markers expression.

Altered bioavailability of epoxyeicosatrienoic acids is associated with conduit artery endothelial dysfunction in type 2 diabetic patients

Background

This pathophysiological study addressed the hypothesis that soluble epoxide hydrolase (sEH), which metabolizes the vasodilator and anti-inflammatory epoxyeicosatrienoic acids (EETs) to dihydroxyeicosatrienoic acids (DHETs), contributes to conduit artery endothelial dysfunction in type 2 diabetes.

Methods and results

Radial artery endothelium-dependent flow-mediated dilatation in response to hand skin heating was reduced in essential hypertensive patients (n = 9) and type 2 diabetic subjects with (n = 19) or without hypertension (n = 10) compared to healthy subjects (n = 36), taking into consideration cardiovascular risk factors, flow stimulus and endothelium-independent dilatation to glyceryl trinitrate. Diabetic patients but not non-diabetic hypertensive subjects displayed elevated whole blood reactive oxygen species levels and loss of NO release during heating, assessed by measuring local plasma nitrite variation. Moreover, plasma levels of EET regioisomers increased during heating in healthy subjects, did not change in hypertensive patients and decreased in diabetic patients. Correlation analysis showed in the overall population that the less NO and EETs bioavailability increases during heating, the more flow-mediated dilatation is reduced. The expression and activity of sEH, measured in isolated peripheral blood mononuclear cells, was elevated in diabetic but not hypertensive patients, leading to increased EETs conversion to DHETs. Finally, hyperglycemic and hyperinsulinemic euglycemic clamps induced a decrease in flow-mediated dilatation in healthy subjects and this was associated with an altered EETs release during heating.

Conclusions

These results demonstrate that an increased EETs degradation by sEH and altered NO bioavailability are associated with conduit artery endothelial dysfunction in type 2 diabetic patients independently from their hypertensive status. The hyperinsulinemic and hyperglycemic state in these patients may contribute to these alterations.

Trial registration NCT02311075. Registered December 8, 2014.

Electronic supplementary material

The online version of this article (10.1186/s12933-019-0843-z) contains supplementary material, which is available to authorized users.

Short- and long-term administration of the non-steroidal mineralocorticoid receptor antagonist finerenone opposes metabolic syndrome-related cardio-renal dysfunction

AIM

To determine whether non-steroidal mineralocorticoid receptor (MR) antagonists oppose metabolic syndrome-related end-organ, i.e. cardiac, damage.

MATERIALS AND METHODS

In Zucker fa/fa rats, a rat model of metabolic syndrome, we assessed the effects of the non-steroidal MR antagonist finerenone (oral 2 mg/kg/day) on left ventricular (LV) function, haemodynamics and remodelling (using echocardiography, magnetic resonance imaging and biochemical methods).

RESULTS

Long-term (90 days) finerenone modified neither systolic blood pressure nor heart rate, but reduced LV end-diastolic pressure and LV end-diastolic pressure-volume relationship, without modifying LV end-systolic pressure and LV end-systolic pressure-volume relationship. Simultaneously, long-term finerenone reduced both LV systolic and diastolic diameters, associated with reductions in LV weight and LV collagen density, while proteinuria and renal nGAL expression were reduced. Short-term (7 days) finerenone improved LV haemodynamics and reduced LV systolic diameter, without modifying LV diastolic diameter. Moreover, short-term finerenone increased myocardial tissue perfusion and reduced myocardial reactive oxygen species, while plasma nitrite levels, an indicator of nitric oxide (NO) bio-availability, were increased.

CONCLUSIONS

In rats with metabolic syndrome, the non-steroidal MR antagonist finerenone opposed metabolic syndrome-related diastolic cardiac dysfunction and nephropathy. This involved acute effects, such as improved myocardial perfusion, reduced oxidative stress/increased NO bioavailability, as well as long-term effects, such as modifications in the myocardial structure.

The IL-1β Antibody Gevokizumab Limits Cardiac Remodeling and Coronary Dysfunction in Rats With Heart Failure

•

Immediate IL-1β antibody gevokizumab administration reduces ischemia/reperfusion related infarct size.

•

Immediate and late IL-1β antibody gevokizumab administration improves heart failure related left ventricular remodeling.

•

IL-1β antibody gevokizumab improves heart failure related coronary dysfunction.

This study reports preclinical data showing that the interleukin (IL)-1β modulation is a new promising target in the pathophysiological context of heart failure. Indeed, in nondiabetic Wistar and diabetic Goto-Kakizaki rats with chronic heart failure induced by myocardial infarction, administration of the IL-1β antibody gevokizumab improves ‘surrogate’ markers of survival (i.e., left ventricular remodeling, hemodynamics, and function as well as coronary function). However, whether IL-1β modulation per se or in combination with standard treatments of heart failure improves long-term outcome in human heart failure remains to be determined.

Impact of soluble epoxide hydrolase inhibition on early kidney damage in hyperglycemic overweight mice

This study addressed the hypothesis that inhibition of the EETs degrading enzyme soluble epoxide hydrolase affords renal protection in the early stage of diabetic nephropathy. The renal effects of the sEH inhibitor t-AUCB (10mg/l in drinking water) were compared to those of the sulfonylurea glibenclamide (80mg/l), both administered for 8 weeks in FVB mice subjected to a high-fat diet (HFD, 60% fat) for 16 weeks. Mice on control chow diet (10% fat) and non-treated HFD mice served as controls. Compared with non-treated HFD mice, HFD mice treated with t-AUCB had a decreased EET degradation, as shown by their higher plasma EETs-to-DHETs ratio, and an increased EET production, as shown by the increase in EETs+DHETs levels, which was associated with induction of CYP450 epoxygenase expression. Both agents similarly reduced fasting glycemia but only t-AUCB prevented the increase in the urinary albumine-to-creatinine ratio in HFD mice. Histopathological analysis showed that t-AUCB reduced renal inflammation, which was associated with an increased mRNA expression of the NFκB inhibitor Iκ≡ and related decrease in MCP-1, COX2 and VCAM-1 expressions. Finally, there was a marginally significant increase in reactive oxygen species production in HFD mice, together with an enhanced NOX2 expression. Both agents did not modify these parameters but t-AUCB increased the expression of the antioxidant enzyme superoxide dismutase 1. These results demonstrate that, independently from its glucose-lowering effect, sEH inhibition prevents microalbuminuria and renal inflammation in overweight hyperglycemic mice, suggesting that this pharmacological strategy could be useful in the management of diabetic nephropathy.

Role of Toll-like receptors 2 and 4 in mediating endothelial dysfunction and arterial remodeling in primary arterial antiphospholipid syndrome

OBJECTIVE

To assess the role of Toll-like receptors (TLRs) in antiphospholipid antibody (aPL)-mediated vascular abnormalities in patients with primary arterial antiphospholipid syndrome (APS).

METHODS

Forty-eight subjects participated in the study. Arterial function and structure and TLR pathway activation were determined in patients with primary arterial APS and matched controls. The pathogenic effects of aPL isolated from patients were assessed in wild-type (WT) and TLR-knockout mice.

RESULTS

APS patients had endothelial dysfunction, arterial stiffening, and hypertrophy, as evidenced by decreased brachial artery endothelium-dependent flow-mediated dilation (FMD) and increased aortic pulse wave velocity and carotid intima-media thickness (IMT), as compared with controls. Plasma samples from APS patients revealed decreased nitric oxide (NO) availability and a pro-oxidative, proinflammatory, and prothrombotic state illustrated by a decrease in nitrite and an increase in lipid peroxidation, tumor necrosis factor α levels, and tissue factor (TF) levels. Furthermore, TLR pathway activation was found in APS patients with increased TLR-2 and TLR-4 messenger RNA expression and increased protein levels of the activated TLR transduction protein interleukin-1 receptor-associated kinase 1 in peripheral blood mononuclear cells. Moreover, agonist-stimulated cell-surface expression of TLR-2 and TLR-4 in circulating monocytes was higher in APS patients than in controls. These changes were positively associated with IMT and negatively associated with FMD. Finally, aPL injection decreased mesenteric endothelium-dependent relaxation and increased TF expression in WT mice but not in TLR-2- or TLR-4-knockout mice.

CONCLUSION

This translational study supports the notion that TLR-2 and TLR-4 play a role in mediating vascular abnormalities in patients with primary arterial APS. TLRs thus constitute a promising pharmacologic target for preventing cardiovascular complications in APS.

Polycystin deficiency induces dopamine-reversible alterations in flow-mediated dilatation and vascular nitric oxide release in humans

Autosomal dominant polycystic kidney disease (ADPKD) is a renal hereditary disorder associated with increased cardiovascular mortality, due to mutations in polycystin-1 and polycystin-2 genes. Endothelial polycystin-deficient cells have an altered mechanosensitivity to fluid shear stress and subsequent deficit in calcium-induced nitric oxide release, prevented by dopamine receptor stimulation. However, the impact of polycystin deficiency on endothelial function in ADPKD patients is still largely unknown. Here we assessed endothelium-dependent flow-mediated dilatation in 21 normotensive ADPKD patients and 21 healthy control subjects, during sustained (hand skin heating) and transient (postischemic hyperemia) flow stimulation. Flow-mediated dilatation was less marked in ADPKD patients than in controls during heating, but it was similar during postischemic hyperemia. There was no difference in endothelium-independent dilatation in response to glyceryl trinitrate. Local plasma nitrite, an indicator of nitric oxide availability, increased during heating in controls but not in patients. Brachial infusion of dopamine in a subset of ADPKD patients stimulated plasma nitrite increase during heating and improved flow-mediated dilatation. Thus, ADPKD patients display a loss of nitric oxide release and an associated reduction in endothelium-dependent dilatation of conduit arteries during sustained blood flow increase. The correction of these anomalies by dopamine suggests future therapeutic strategies that could reduce the occurrence of cardiovascular events in ADPKD.

Gene deletion of protein tyrosine phosphatase 1B protects against sepsis-induced cardiovascular dysfunction and mortality

OBJECTIVE

Cardiovascular dysfunction is a major cause of mortality in patients with sepsis. Recently, we showed that gene deletion or pharmacological inhibition of protein tyrosine phosphatase 1B (PTP1B) improves endothelial dysfunction and reduces the severity of experimental heart failure. However, the cardiovascular effect of PTP1B invalidation in sepsis is unknown. Thus, we explored the beneficial therapeutic effect of PTP1B gene deletion on lipopolysaccharide (LPS)-induced cardiovascular dysfunction, inflammation, and mortality.

APPROACH AND RESULTS

PTP1B(-/-) or wild-type mice received LPS (15 mg/kg) or vehicle followed by subcutaneous fluid resuscitation (saline, 30 mL/kg). α-1-dependent constriction and endothelium-dependent dilatation, assessed on isolated perfused mesenteric arteries, were impaired 8 hours after LPS and significantly improved in PTP1B(-/-) mice. This was associated with reduced vascular expression of interleukin1-β, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, cyclooxygenase-2, and inducible nitric oxide synthase mRNA. PTP1B gene deletion also limited LPS-induced cardiac dysfunction assessed by echocardiography, left ventricular pressure-volume curves, and in isolated perfused hearts. PTP1B(-/-) mice also displayed reduced LPS-induced cardiac expression of tumor necrosis factor-α, interleukin1-β, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and Gp91phox, as well as of several markers of cellular infiltration. PTP1B deficiency also reduced cardiac P38 and extracellular signal-regulated protein kinase 1 and 2 phosphorylation and increased phospholamban phosphorylation. Finally, PTP1B(-/-) mice displayed a markedly reduced LPS-induced mortality, an effect also observed using a pharmacological PTP1B inhibitor. PTP1B deletion also improved survival in a cecal ligation puncture model of sepsis.

CONCLUSIONS

PTP1B gene deletion protects against septic shock-induced cardiovascular dysfunction and mortality, and this may be the result of the profound reduction of cardiovascular inflammation. PTP1B is an attractive target for the treatment of sepsis.

Utilisation de l'acide gamma-hydroxybutyrique (ghb) dans les rave-parties et pour la soumission chimique en france : mythe ou réalité?

Since many years gamma-hydroxybutyric acid (GHB) is presented as very popular in rave-parties and for bodybuilders. It seems to be a controversy between media coverage and the results of toxicological analysis done in high-level laboratories. In order to clarify this problem, we compiled the data of 6 laboratories. They used the same analytical method by GC/MS. Depending the laboratory, the limit of detection was 1-2 μg/mL and the limit of quantification was 2.5-5 μg/ mL. Two labs where looking for GHB in each forensic case (100 and 150 cases a year). Others labs performed GHB analysis only on specific request (each 10 cases a year). Mean time between ingestion of GHB and blood/urine sampling was 12-48 h. Mean time between sampling and analysis was much higher (a few hours to a few month. All samples were stored at +4°C. Only 3 cases were considered as positive (blood GHB : 165, 132 and 114 μg/mL, urine GHB : 7450 and 436 μg/ mL) They were admitted in an hospital EU. Interpreting results remains very difficult because GHB is endogenous, present in blood and urine, and its half-life is very short. One has to report only « positive » GHB results when amounts are higher than 5 μg/mL in blood and 10 μg/mL in urine. Obviously, forensic toxicologists have to play a very important part in diagnosis of GHB intoxications and estimating its frequency. Actually, because the lack of data in France, it is not possible to answer the question asked in the title of this paper.

High-efficiency on-line haemodiafiltration improves conduit artery endothelial function compared with high-flux haemodialysis in end-stage renal disease patients

BACKGROUND

Middle molecular weight uraemic toxins are considered to play an important role in vascular dysfunction and cardiovascular outcomes in end-stage renal disease (ESRD) patients. Recent dialysis techniques based on convection, specifically high-efficiency on-line haemodiafiltration (HDF), enhance the removal of middle molecular weight toxins and reduce all-cause mortality in haemodialysis (HD) patients. However, the mechanisms of these improved outcomes remain to be established.

METHODS

This prospective study randomly assigned 42 ESRD patients to switch from high-flux HD to high-efficiency on-line HDF (n=22) or to continue HD (n=20). Brachial artery endothelium-dependent flow-mediated dilatation, central pulse pressure, carotid artery intima-media thickness (IMT), internal diastolic diameter and distensibility and circulating markers of uraemia, inflammation and oxidative stress were blindly assessed before and after a 4-month follow-up.

RESULTS

Brachial flow-mediated dilatation and carotid artery distensibility increased significantly in the HDF group compared with HD, while carotid IMT and diameter remained similar. HDF decreased predialysis levels of the uraemic toxins β2-microglobulin, phosphate and blood TNFα mRNA expression. Oxidative stress markers were not different between the HD and HDF groups. Blood mRNA expression of protein kinase C β2, an endothelial NO-synthase (eNOS) inhibitor, decreased significantly with HDF.

CONCLUSIONS

High-efficiency on-line HDF prevents the endothelial dysfunction and stiffening of the conduit arteries in ESRD patients compared with high-flux HD. HDF decreases uraemic toxins, vascular inflammation, and is associated with subsequent improvement in eNOS functionality. These results suggest that reduced endothelial dysfunction may be an intermediate mechanism explaining the beneficial outcomes associated with HDF.

[Prioritization of healthcare programs by pharmacy students from France and from Quebec, according to the perceived impact of a decentralized pharmacist]

INTRODUCTION

Healthcare decision makers need to establish priorities and their decisions must be justified. However, few data is available on the prioritization process of the healthcare programs that should benefit from decentralized pharmacists.

PATIENTS AND METHODS

The main objective was to prioritize healthcare programs according to the perceived impact of a decentralized pharmacist for outpatient and inpatient clienteles. The secondary objective was to compare the prioritization made by pharmacy students from two Quebec universities and from one French university. Two different approaches were developed (perceived impact according to three indicators and according to the global impact).

RESULTS

The majority of healthcare programs with a high evidence based literature quality score (5/6 outpatient programs and 5/8 inpatient programs) were highly prioritized by at least two out of three cohorts. The median rank that was attributed for each healthcare program was significantly different between the three cohorts for 8/17 (47%) of outpatient programs and for 10/18 (56%) of inpatient programs.

DISCUSSION

A higher rank was attributed to healthcare programs when the evidence based literature quality score was high. The prioritization was also influenced by the difference in pharmaceutical practice between France and Quebec (e.g. sterilization and medical devices in France).

CONCLUSIONS

This study presented two approaches for the prioritization of healthcare programs that should benefit from a decentralized pharmacist, according to students from France and from Quebec.

Aldosterone synthase inhibition improves cardiovascular function and structure in rats with heart failure: a comparison with spironolactone

AIMS

Inhibition of aldosterone synthase, the key enzyme in aldosterone formation, could be an alternative strategy for mineralocorticoid-receptor antagonists in congestive heart failure (CHF), but its effect in CHF is unknown.

METHODS AND RESULTS

We compared, in rats with CHF, the effects of a 7 day and a 12 week treatment with the aldosterone synthase inhibitor FAD286 (4 mg kg(-1) day(-1)) with those induced by spironolactone (80 mg kg(-1) day(-1)). FAD286/spironolactone increased cardiac output without modifying arterial pressure. Long-term FAD286 and spironolactone reduced left ventricular (LV) end-diastolic pressure, LV relaxation constant, and LV dilatation, and these effects were more marked with FAD286, whereas both drugs reduced LV hypertrophy and collagen accumulation to the same extent. Long-term FAD286/spironolactone prevented CHF-related enhancement in LV ACE and reduction in LV ACE-2, but only FAD286 prevented the reduction in LV AT(2) receptors. FAD286, but not long-term spironolactone, reduced the CHF-related enhancements in LV reactive oxygen species, reduced-oxidized glutathione ratio, and aortic nicotinamide adenine dinucleotide phosphate oxidase activity. FAD286 normalized the CHF-induced impairment of endothelium-dependent vasodilatation.

CONCLUSION

In experimental CHF, FAD286 and spironolactone improve LV haemodynamics, remodelling, and function, but only FAD286 persistently normalizes LV 'redox status'. These results suggest that aldosterone synthase inhibition is a potential therapeutic strategy for the treatment of CHF.

Intestinal preconditioning prevents inflammatory response by modulating heme oxygenase-1 expression in endotoxic shock model

Gut mucosal injury observed during ischemia-reperfusion is believed to trigger a systemic inflammatory response leading to multiple organ failure. It should be interesting to demonstrate this relationship between gut and multiple organ failure in a sepsis model. Intestinal preconditioning (PC) can be used as a tool to assess the effect of intestinal ischemia in inflammatory response after LPS challenge. The aim of this study was to investigate the protective effect of PC against LPS-induced systemic inflammatory and intestinal heme oxygenase-1 (HO-1) expression. ES was performed with LPS (10 mg/kg iv) with or without PC, which was done before LPS. Rats were first subjected to sham surgery or PC with four cycles of 1 min ischemia and 4 min of reperfusion 24 h before LPS challenge or saline administration. PC significantly reduced fluid requirements, lung edema, intestinal lactate production, and intestinal injury. Inflammatory mRNA expressions for intestine and lung ICAM and TNF were significantly reduced after PC, and these effects were significantly abolished by zinc-protoporphyrin (a specific HO-1 activity inhibitor) and mimicked by bilirubin administration. Intestinal PC selectively increased HO-1 mRNA expression in intestine, but we have observed no expression in lungs. These findings demonstrate that intestinal injury is a important event for inflammatory response and multiple organ injury after LPS challenge. Intestinal HO-1 expression attenuates LPS-induced multiple organ failure by modulating intestine injury and its consequences on inflammatory response. Identification of the exact mechanisms responsible for intestine HO-1 induction may lead to the development of new pharmacological interventions.

Protective effects of heme-oxygenase expression against endotoxic shock: inhibition of tumor necrosis factor-alpha and augmentation of interleukin-10

BACKGROUND

Heme-oxygenase (HO)-1 acts as an inducible defense against oxidative stress and could play an important role in inflammation models, providing protection against oxidative stress and systemic inflammatory response. The objective of this study was to improve the role of HO-1 on systemic inflammatory response in an endotoxic shock model.

METHODS

Five groups of animals were used: control group; lipopolysaccharide (LPS) group, animals received LPS 5 mg/kg; hemin + LPS group, animals received pretreatment with hemin, used to induce HO-1 expression; Zn-PP group, animals received Zn-PP, a specific inhibitor of HO-1 activity and hemin group. At the end of the experiment, tissue and blood samples were isolated for the measurement of HO-1 mRNA expression, biochemical measurements, and cytokine measurements.

RESULTS

HO-1 messenger RNA expression and protein were induced to a larger extent in LPS group in distal organs. Hemin pretreatment induced a significant decrease oxidative stress and tumor necrosis factor-alpha plasma levels with a significant increase of interleukin-10 plasma levels. Pulmonary injury was markedly limited after hemin. Onset of lethality in LPS group occurred at H6, and was delayed until H10 with hemin. Inhibition of HO-1 activity by Zn-PP administration abolished the beneficial effect of hemin-pretreatment.

CONCLUSIONS

Early HO-1 expression may modulate systemic inflammatory response and limit end-organ injury in endotoxic shock model.

Triple ACE-ECE-NEP Inhibition in Heart Failure: A Comparison With ACE and Dual ECE-NEP Inhibition

Mortality remains high in chronic heart failure (CHF) because under ACE inhibitor treatment other neurohumoral systems remain/become (de)activated, such as the endothelin and atrial natriuretic peptide pathways. Dual endothelin-converting enzyme-neutral endopeptidase (ECE-NEP) inhibition exerts beneficial effects in experimental CHF, but whether "triple" ACE-ECE-NEP inhibition is superior to ACE or ECE-NEP inhibition is unknown. We compared, in rats with CHF, ACE-ECE-NEP to ACE or ECE-NEP inhibition in terms of left ventricular (LV) hemodynamics and remodeling. Benazepril (2 mg/kg/d) or the ECE-NEP inhibitor CGS26303 (10 mg/kg/d) were administered alone or in combination (subcutaneously for 28 days starting 7 days after coronary ligation). ACE-ECE-NEP inhibition reduced blood pressure more markedly than ACE or ECE-NEP inhibition. All treatments increased cardiac output to the same extent, but ACE-ECE-NEP inhibition reduced LV diameter and LV end-diastolic pressure more markedly than ACE or ECE-NEP inhibition. The reduction of LV weight and collagen accumulation in the "viable" myocardium was most pronounced after ACE-ECE-NEP inhibition. These results, obtained in experimental CHF, illustrate a further improvement of LV hemodynamics and structure after ACE-ECE-NEP inhibition compared with either ACE or ECE-NEP inhibition, but whether this is associated with a further improvement of exercise tolerance and/or survival remains to be determined.

CHRONIC DECREASE IN FLOW CONTRIBUTES TO HEART FAILURE-INDUCED ENDOTHELIAL DYSFUNCTION IN RATS

Chronic heart failure (CHF) impairs endothelium-dependent, nitric oxide (NO)-mediated dilation. This decreased dilation may be partly secondary to the chronic decrease in blood flow, but this hypothesis has not yet been tested. Thus, we assessed whether a localized, chronic increase in blood flow in vivo reverses endothelial dysfunction of small arteries in rats with CHF. Two months after coronary artery ligation or sham surgery, second-order side branches of the superior mesenteric artery were ligated in order to obtain persistently elevated blood flow (HF) in the adjacent first-order side branch compared with normal vessels (NF). One month later, responses to acetylcholine and flow-mediated vasodilatation (FMD) were assessed in vitro in an arteriograph. Chronic heart failure induced a decrease in mesenteric blood flow (374 +/- 25 and 305 +/- 27 micro L/min for sham and CHF, respectively; P < 0.05). Neither CHF nor the chronic increase in flow affected the responses to acetylcholine. Chronic heart failure decreased FMD (maximal response in sham and control 34 +/- 6 and 13 +/- 4%, respectively; P < 0.05). Chronic increases in blood flow did not modify FMD in sham, but restored FMD in CHF rats (28 +/- 4%; P < 0.05 vs CHF NF). The restored response was abolished by an inhibitor of NO synthesis (N(G)-nitro-l-arginine). Chronic heart failure did not affect the abundance of mesenteric endothelial NO synthase (eNOS) mRNA. A chronic increase in flow significantly increased the abundance of eNOS mRNA in sham rats, but only moderately and non-significantly in CHF rats. Thus, endothelial dysfunction of small arteries in CHF appears to be largely the consequence of the chronic decrease in flow.

Long-Term Heart Rate Reduction Induced by the Selective I f Current Inhibitor Ivabradine Improves Left Ventricular Function and Intrinsic Myocardial Structure in Congestive Heart Failure

BACKGROUND

Heart rate reduction (HRR) improves left ventricular (LV) filling, increases myocardial O2 supply, and reduces myocardial O2 consumption, which are all beneficial in congestive heart failure (CHF). However, the long-term effects of HRR on cardiac function and remodeling are unknown.

METHODS AND RESULTS

We assessed, in rats with CHF, the effects of long-term HRR induced by the selective I(f) current inhibitor ivabradine (as food admix for 90 days starting 7 days after coronary artery ligation). To assess intrinsic modifications of LV tissue induced by long-term HRR, all parameters were reassessed 3 days after interruption of treatment. Ivabradine decreased heart rate over the 90-day treatment period (-18% versus untreated at 10 mg x kg(-1) x d(-1)), without modifying blood pressure, LV end-diastolic pressure, or dP/dt(max/min). Ivabradine significantly reduced LV end-systolic but not end-diastolic diameter, which resulted in preserved cardiac output due to increased stroke volume. In the Langendorff preparation, ivabradine shifted LV systolic but not end-diastolic pressure-volume relations to the left. Ivabradine decreased LV collagen density and increased LV capillary density without modifying LV weight. Three days after interruption of treatment, the effects of ivabradine on LV geometry, shortening, and stroke volume persisted despite normalization of heart rate.

CONCLUSIONS

In rats with CHF, long-term HRR induced by the selective I(f) inhibitor ivabradine improves LV function and increases stroke volume, preserving cardiac output despite the HRR. The improvement of cardiac function is related not only to the HRR per se but also to modifications in the extracellular matrix and/or function of myocytes as a consequence of long-term HRR.

Sustained Improvement of Cardiac Function and Prevention of Cardiac Remodeling after Long-Term Dual ECE-NEP Inhibition in Rats with Congestive Heart Failure

Acute inhibition of endothelin converting enzyme (ECE) and neutral endopeptidase (NEP) exerts beneficial hemodynamic effects in chronic heart failure (CHF). However, the long-term effects of dual ECE-NEP inhibition are unknown. We evaluated, in rats with CHF, the long-term effects of the dual ECE-NEP inhibitor CGS 26303 (10 mg.kg(-1).day(-1)) on systemic and left ventricular (LV) hemodynamics and LV remodeling, and compared them to those induced by the selective NEP inhibitor CGS 24592 (10 mg.kg(-1).day(-1)), both administered subcutaneously by mini-pump for 30 days starting 7 days after left coronary artery ligation. After 30 days, CGS 26303, but not CGS 24592, reduced systolic blood pressure, while both drugs never affected heart rate. Echocardiographic studies showed that only CGS 26303 diminished LV end-diastolic and systolic diameters and increased LV fractional shortening and cardiac output. Moreover, CGS 26303, but not CGS 24592, reduced LV end-diastolic pressure, while LV dP/dtmax/min was not affected. Both drugs reduced collagen accumulation in the 'viable' part of the LV, but only CGS 26303 reduced LV weight. Thus, long-term treatment with CGS 26303 decreases both preload and afterload, increases cardiac output, and diminishes LV hypertrophy, dilatation, and cardiac fibrosis, suggesting that dual ECE-NEP inhibition might be beneficial in human CHF.

Prolonged Cardiac Dysfunction After Withdrawal of Chronic Cocaine Exposure in Rats

Cocaine abuse causes myocardial dysfunction and induces oxidative stress. However, the reversibility of these effects is unknown. We evaluated myocardial function and oxidative stress after cocaine withdrawal, in a rat model of chronic cocaine exposure. Standard echocardiography and Doppler tissue imaging were performed after 4 weeks (W4) of cocaine administration (2 x 7.5 mg/kg/d, i.p.) and 4 weeks after interruption (W8). At these time points, redox state (reduced glutathione GSH, oxidized glutathione GSH, and GSH/GSSG) as well as activities of GSH peroxidase (GPX), superoxide dismutase (SOD), and catalase were determined in the left ventricle (LV). At W4, LV fractional shortening, posterior wall thickening, systolic myocardial ventricular gradient (SMVG), dP/dt(max), and dp/dt(min) were decreased, compared with control values while LV myocardial thickness was increased. At W8, even though dP/dtmax and dp/dt(min) were restored, myocardial function was still impaired as demonstrated by the decrease in posterior wall thickening, and systolic myocardial velocity gradient. At W4, CAT and GPX activities as well as GSH/GSSG ratio were reduced while SOD activity was increased. Antioxidant markers and redox ratio remained altered 4 weeks after the last injection. Thus, these data demonstrate the persistence of LV dysfunction after cocaine withdrawal, which occurs in a context of a deficit in antioxidant defenses.

Role of reactive oxygen species in cocaine-induced cardiac dysfunction

OBJECTIVE

Contractility alterations and LV hypertrophy after chronic cocaine administration have been shown to be accompanied by an increase in oxidative stress. This study was carried out to investigate whether the production of reactive oxygen species is an early event of primary importance in cocaine-induced myocardial injury or simply occurs as a consequence of the ventricular dysfunction itself.

METHODS AND RESULTS

After 2 days of cocaine administration to rats, no differences were observed in echocardiographic parameters between the cocaine-treated group and the control group. However, an increase in oxidative stress in the myocardium was indicated by an increase in lipid peroxidation (+35%, cocaine vs. control), an increase in antioxidant enzymes (catalase +110%, glutathione peroxidase +40% and superoxide dismutase +38%) and of NADPH-driven superoxide production (assessed by chemiluminescence). Furthermore, higher gp91phox and p22phox mRNA expression, measured by quantitative real-time RT-PCR, was found in the cocaine group. On day 8, cocaine administration induced a cardiac dysfunction, characterized by a decrease in cardiac index (-30%, cocaine vs. controls) and left ventricular (LV) fractional shortening (-23%, cocaine vs. controls). This LV dysfunction was prevented by antioxidant treatment (100 mg/kg/day vitamin C and 100 U/kg/day vitamin E). Moreover, in these animals, antioxidant treatment decreased lipid peroxides and decreased the activity of NADPH oxidase, associated with the downregulation of gp91phox.

CONCLUSION

These data indicate that cocaine administration induces early NADPH-driven O2-. release which may play an important role in the development and progression of the LV dysfunction observed after chronic cocaine abuse.