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IMPLICATION OF TRANSCRIPTIONAL FACTOR RUNX2 IN PULMONARY ARTERIAL HYPERTENSION
S124
fraction (Simpson method), longitudinal strain imaging, intraventricular pressure gradient) and diastolic function (diastolic longitudinal strain rate and intraventricular vortex size) were assessed. The intracardiac pressure gradients were estimated by processing color M-mode Doppler data using the Euler equation of fluid dynamics and indexed (i) by the systolic arterial pressure of the participant. Vortex size was assessed by post-processing a 3chamber color Doppler image using our own algorhythm in Matlab and expressed as (vortex surface x 100)/(LV surface). These echo data were compared to clinical characteristics: blood pressure, weight, medical history and past and current training. RESULTS: Among female rugby players, only one was diagnosed with pre-hypertension while 85% of the male players had either pre- or confirmed hypertension (P ¼ 0.0001). Increased LV mass was significantly associated with hypertension status (P¼0.01) but unrelated to past or current training load. Decrease in both systolic and diastolic function were significantly associated with an increase in LV mass: longitudinal strain R¼-0.4, P¼0.01; intraventricular pressure gradient R¼-0.6, P<0.001 (see figure); longitudinal diastolic strain rate R¼-0.5, P¼0.003 and vortex size R¼-0.3, P¼0.04 CONCLUSION: Cardiac remodeling in rugby and American football line players is linked to hypertension and associated with both subclinical systolic and diastolic function. Careful evaluation of remodeling and consideration of hypertension should be performed in these athletes before assigning the diagnosis of athlete’s heart.
Canadian Journal of Cardiology Volume 30 2014
hemodynamics assessed in a substudy is reported (NCT00660179). METHODS: 742 PAH patients were randomised to placebo, macitentan 3mg or 10mg, once daily. Stable Background PAH therapy, except injectable prostanoids and other ERAs, were allowed. At selected centres patients underwent right heart catheterisation at randomisation and Month 6. Changes from baseline to Month 6 for mean right atrial pressure (mRAP), mean pulmonary arterial pressure (mPAP), pulmonary vascular resistance (PVR), cardiac index (CI) and mixed venous oxygen saturation (SvO2) were calculated for all patients and stratified in an exploratory analysis for background PAH therapy and baseline WHO FC I/II vs III/IV. Median treatment effects (95% CL) between placebo and macitentan are reported. RESULTS: 187 patients participated in the substudy (51% were treatment-naïve and 56% in WHO FC III/IV). Baseline median values for all patients on placebo (n¼68), macitentan 3mg (n¼62) and 10mg (n¼57) were: mRAP 7.0, 8.0, 7.0 mmHg; mPAP 52.0, 54.0, 52.3 mmHg; PVR 800, 785, 789 dyn$sec/cm5; CI 2.49, 2.23, 2.47 L/min/m2; and SvO2 66.0, 64.5, 66.5%. Overall, hemodynamic parameters improved at Month 6 with macitentan and worsened with placebo. The table shows beneficial treatment effects with macitentan that were statistically significant (p<0.05) for PVR and CI for both subgroups (except PVR macitentan 3mg treatmentnaïve). CONCLUSION: Macitentan significantly improved cardiopulmonary hemodynamics in PAH patients. Improvements in PVR and CI were consistent irrespective of Background PAH therapy and baseline WHO FC.
137 EFFECT OF MACITENTAN ON HEMODYNAMICS IN PATIENTS WITH PULMONARY ARTERIAL HYPERTENSION: RESULTS FROM THE LONG-TERM, RANDOMISED, PLACEBO-CONTROLLED SERAPHIN TRIAL
138 IMPLICATION OF TRANSCRIPTIONAL FACTOR RUNX2 IN PULMONARY ARTERIAL HYPERTENSION
N Hirani, J Granton, RD Levy, S Mehta, L Perchenet, S Provencher, N Galiè, L Rubin, G Simonneau, O Sitbon, A Torbicki
Québec, Québec
Calgary, Alberta BACKGROUND:
Macitentan, a novel dual endothelin receptor antagonist (ERA), significantly reduced morbidity and mortality in pulmonary arterial hypertension (PAH) patients in the Phase III SERAPHIN trial. The effect of macitentan on
G Ruffenach, S Breuils-Bonnet, E Tremblay, S Provencher, S Bonnet BACKGROUND:
Pulmonary arterial hypertension (PAH) is a vascular remodeling disease characterized by enhanced pulmonary artery smooth muscle cells (PASMC) proliferation and suppressed apoptosis. Numerous biological pathways have been implicated in the sustainability of this phenotype, including P21, Bcl-2 along with the STAT3/NFAT axis. Several studies
Abstracts
S125
have demonstrated that miR-204 is downregulated in PAH. Interestingly, miR-204 directly regulates the expression of the transcription factor RUNX2, which is implicated in many features characterizing PAH, including modulation of the BMPR2, P21, and Bcl2 pathways. Thus we hypothesized that a miR-204 dependent upregulation of Runx2 in PAH promotes PASMC proliferation and resistance to apoptosis. METHODS AND RESULTS: Using human explanted lungs, fresh distal PAs and freshly isolated PASMC from both control and PAH patients (n¼5 to 12), we demonstrated a significant (p<0.05) upregulation of RUNX2 (qRT-PCR, western blot and immunofluorescence) in PAH compared to controls. Gain and loss functions experiments in PASMC showed that downregulation of miR-204 in control PASMC increases RUNX2 expression, while increases in miR-204 in PAHPASMC decreases it (n¼3 to 5 p<0.05). Increased RUNX2 expression was associated with a downregulation of P21 and an upregulation of Bcl2 (n¼3 to 8 p<0.05). More importantly, restoring miR-204 or decreasing RUNX2 expression decreases proliferation (Ki67), resistance to apoptosis (TUNEL) in human PAH-PASMC (n¼3 p<0.05), while upregulating RUNX2 in control PASMC using an adenovirus mimic PAH phenotype (n¼3 p<0.05). Finally, in Sugen/hypoxia rat model of PAH, nebulization of RUNX2 siRNA (n¼15) decreases mean PA pressure, pulmonary vascular resistance, and increase exercise tolerance and cardiac output (p<0.05). CONCLUSION: Taken together, our study uncovers a new miR204-RUNX2 axis contributing to a P21-dependent proproliferative and Bcl2-depedent anti-apoptotic phenotype in PAH-PASMC.
Correspondingly, heme-arginate potentiated the aberrant expression of nephrin alongside other fundamental regulators of podocyte such as podocalyxin, podocin and CD2-associatedprotein (CD2AP). These were associated with improved renal function, evidenced by reduced albuminuria and proteinuria, while creatinine clearance increased. The renoprotection by heme-arginate was accompanied by the reduction of several inflammatory/oxidative mediators such as nuclear factor-kappaB, macrophage-inflammatory-protein-1-alpha, macrophagechemoattractant-protein-1, tumor-necrosis factor-alpha, IL-6, IL1b, 8-isoprostan, endothelin-1 and aldosterone. These were associated with significant enhancement of adiponectin, HO-1, HO-activity, cGMP and atrial-natriuretic-peptide (ANP), whereas the HO-inhibitor, chromium-mesoporphyrin nullified the reno-protection and exacerbated renal dysfunction. CONCLUSION AND IMPLICATIONS: Heme-arginate improves renal function by reducing histo-pathological lesions, abating inflammatory/oxidative mediators, attenuating profibrotic/ extracellular-matrix proteins and attenuating albuminuria/ proteinuria, while simultaneously potentiating the HOadiponectin-ANP axis with associated increase in nephrin, podocin, podocalyxin, CD2AP and creatinine clearance.
139 HEME OXYGENASE MODULATES PODOCYTE-ASSOCIATED PROTEINS TO IMPROVE RENAL FUNCTION IN HYPERTENSION
Edmonton, Alberta
J Ndisang BACKGROUND:
Although heme-oxygenase (HO) is cytoprotective, its effects on podocyte proteins like podocalyxin, podocin, CD2-associated protein in renal dysfunction in Nu-nitro-L-arginine-methyl-ester (L-NAME) hypertension are largely unclear. EXPERIMENTAL APPROACH: Hypertension was induced in healthy Sprague-Dawley rats via the administration of L-NAME for 4 weeks. HO was enhanced with heme-arginate or inhibited with chromium-mesoporphyrin and several assays including Enzyme-immunoassay, ELISA, histology/morphology, spectrophotometry and Western-immunoblotting were used. RESULTS: Treatment with heme-arginate reduced several kidney histo-pathological lesions including, tubular-atrophy/ fibrosis, glomerular abnormalities, renal-arteriolar thickening, tubular-cast and mononuclear cell-infiltration in L-NAMEhypertensive rats. In addition, heme-arginate abated the elevated levels of renal extracellular-matrix/pro-fibrotic proteins like collagen and fibronectin that deplete nephrin, an important trans-membrane protein critical for the formation of the scaffoldings of the podocyte slit-diaphragm that allows small ions to filter, but not massive excretion of proteins, hence proteinuria.
140 A RANDOMIZED TRIAL OF THE EFFECT OF PHARMACIST PRESCRIBING ON IMPROVING BLOOD PRESSURE IN THE COMMUNITY: THE ALBERTA CLINICAL TRIAL IN OPTIMIZING HYPERTENSION (RXACTION) RT Tsuyuki, SK Houle, T Charrois, M Kolber, MM Rosenthal, RZ Lewanczuk, D Cooney, FA McAlister BACKGROUND:
Hypertension control rates in Canada remain suboptimal. In Alberta, pharmacists may apply for Additional Prescribing Authorization, allowing them to prescribe drug therapy for patients. This provides a new option for improving access to hypertension care. The objective of this study was to determine the impact of pharmacist care (including prescribing) on systolic blood pressure (SBP) in patients with uncontrolled hypertension. METHODS: DESIGN: Randomized controlled trial with patients as the unit of randomization, with care provided by 22 Alberta pharmacists with prescribing authorization. PATIENTS: Adults with BP above recommended targets (>140/90 or >130/ 80mmHg if diabetic) based upon measurements over multiple visits. Enhanced Care: Pharmacist assessment, BP wallet card, education on hypertension, pharmacist prescribing of antihypertensive drugs and laboratory monitoring using current Canadian guidelines, and monthly follow-up visits dropping down to every 3 months if target BP was achieved for 2 consecutive visits. All patients were followed for 6 months. CONTROL: Wallet card for BP recording, patient information materials on hypertension, and no study specific follow-up. Outcomes: Primary outcome was the difference in change in systolic BP between the intervention and control groups at 6 months. RESULTS: A total of 248 patients were randomized to the study. The mean (SD) patient age was 63.5 (12.7) years,
fraction (Simpson method), longitudinal strain imaging, intraventricular pressure gradient) and diastolic function (diastolic longitudinal strain rate and intraventricular vortex size) were assessed. The intracardiac pressure gradients were estimated by processing color M-mode Doppler data using the Euler equation of fluid dynamics and indexed (i) by the systolic arterial pressure of the participant. Vortex size was assessed by post-processing a 3chamber color Doppler image using our own algorhythm in Matlab and expressed as (vortex surface x 100)/(LV surface). These echo data were compared to clinical characteristics: blood pressure, weight, medical history and past and current training. RESULTS: Among female rugby players, only one was diagnosed with pre-hypertension while 85% of the male players had either pre- or confirmed hypertension (P ¼ 0.0001). Increased LV mass was significantly associated with hypertension status (P¼0.01) but unrelated to past or current training load. Decrease in both systolic and diastolic function were significantly associated with an increase in LV mass: longitudinal strain R¼-0.4, P¼0.01; intraventricular pressure gradient R¼-0.6, P<0.001 (see figure); longitudinal diastolic strain rate R¼-0.5, P¼0.003 and vortex size R¼-0.3, P¼0.04 CONCLUSION: Cardiac remodeling in rugby and American football line players is linked to hypertension and associated with both subclinical systolic and diastolic function. Careful evaluation of remodeling and consideration of hypertension should be performed in these athletes before assigning the diagnosis of athlete’s heart.
Canadian Journal of Cardiology Volume 30 2014
hemodynamics assessed in a substudy is reported (NCT00660179). METHODS: 742 PAH patients were randomised to placebo, macitentan 3mg or 10mg, once daily. Stable Background PAH therapy, except injectable prostanoids and other ERAs, were allowed. At selected centres patients underwent right heart catheterisation at randomisation and Month 6. Changes from baseline to Month 6 for mean right atrial pressure (mRAP), mean pulmonary arterial pressure (mPAP), pulmonary vascular resistance (PVR), cardiac index (CI) and mixed venous oxygen saturation (SvO2) were calculated for all patients and stratified in an exploratory analysis for background PAH therapy and baseline WHO FC I/II vs III/IV. Median treatment effects (95% CL) between placebo and macitentan are reported. RESULTS: 187 patients participated in the substudy (51% were treatment-naïve and 56% in WHO FC III/IV). Baseline median values for all patients on placebo (n¼68), macitentan 3mg (n¼62) and 10mg (n¼57) were: mRAP 7.0, 8.0, 7.0 mmHg; mPAP 52.0, 54.0, 52.3 mmHg; PVR 800, 785, 789 dyn$sec/cm5; CI 2.49, 2.23, 2.47 L/min/m2; and SvO2 66.0, 64.5, 66.5%. Overall, hemodynamic parameters improved at Month 6 with macitentan and worsened with placebo. The table shows beneficial treatment effects with macitentan that were statistically significant (p<0.05) for PVR and CI for both subgroups (except PVR macitentan 3mg treatmentnaïve). CONCLUSION: Macitentan significantly improved cardiopulmonary hemodynamics in PAH patients. Improvements in PVR and CI were consistent irrespective of Background PAH therapy and baseline WHO FC.
137 EFFECT OF MACITENTAN ON HEMODYNAMICS IN PATIENTS WITH PULMONARY ARTERIAL HYPERTENSION: RESULTS FROM THE LONG-TERM, RANDOMISED, PLACEBO-CONTROLLED SERAPHIN TRIAL
138 IMPLICATION OF TRANSCRIPTIONAL FACTOR RUNX2 IN PULMONARY ARTERIAL HYPERTENSION
N Hirani, J Granton, RD Levy, S Mehta, L Perchenet, S Provencher, N Galiè, L Rubin, G Simonneau, O Sitbon, A Torbicki
Québec, Québec
Calgary, Alberta BACKGROUND:
Macitentan, a novel dual endothelin receptor antagonist (ERA), significantly reduced morbidity and mortality in pulmonary arterial hypertension (PAH) patients in the Phase III SERAPHIN trial. The effect of macitentan on
G Ruffenach, S Breuils-Bonnet, E Tremblay, S Provencher, S Bonnet BACKGROUND:
Pulmonary arterial hypertension (PAH) is a vascular remodeling disease characterized by enhanced pulmonary artery smooth muscle cells (PASMC) proliferation and suppressed apoptosis. Numerous biological pathways have been implicated in the sustainability of this phenotype, including P21, Bcl-2 along with the STAT3/NFAT axis. Several studies
Abstracts
S125
have demonstrated that miR-204 is downregulated in PAH. Interestingly, miR-204 directly regulates the expression of the transcription factor RUNX2, which is implicated in many features characterizing PAH, including modulation of the BMPR2, P21, and Bcl2 pathways. Thus we hypothesized that a miR-204 dependent upregulation of Runx2 in PAH promotes PASMC proliferation and resistance to apoptosis. METHODS AND RESULTS: Using human explanted lungs, fresh distal PAs and freshly isolated PASMC from both control and PAH patients (n¼5 to 12), we demonstrated a significant (p<0.05) upregulation of RUNX2 (qRT-PCR, western blot and immunofluorescence) in PAH compared to controls. Gain and loss functions experiments in PASMC showed that downregulation of miR-204 in control PASMC increases RUNX2 expression, while increases in miR-204 in PAHPASMC decreases it (n¼3 to 5 p<0.05). Increased RUNX2 expression was associated with a downregulation of P21 and an upregulation of Bcl2 (n¼3 to 8 p<0.05). More importantly, restoring miR-204 or decreasing RUNX2 expression decreases proliferation (Ki67), resistance to apoptosis (TUNEL) in human PAH-PASMC (n¼3 p<0.05), while upregulating RUNX2 in control PASMC using an adenovirus mimic PAH phenotype (n¼3 p<0.05). Finally, in Sugen/hypoxia rat model of PAH, nebulization of RUNX2 siRNA (n¼15) decreases mean PA pressure, pulmonary vascular resistance, and increase exercise tolerance and cardiac output (p<0.05). CONCLUSION: Taken together, our study uncovers a new miR204-RUNX2 axis contributing to a P21-dependent proproliferative and Bcl2-depedent anti-apoptotic phenotype in PAH-PASMC.
Correspondingly, heme-arginate potentiated the aberrant expression of nephrin alongside other fundamental regulators of podocyte such as podocalyxin, podocin and CD2-associatedprotein (CD2AP). These were associated with improved renal function, evidenced by reduced albuminuria and proteinuria, while creatinine clearance increased. The renoprotection by heme-arginate was accompanied by the reduction of several inflammatory/oxidative mediators such as nuclear factor-kappaB, macrophage-inflammatory-protein-1-alpha, macrophagechemoattractant-protein-1, tumor-necrosis factor-alpha, IL-6, IL1b, 8-isoprostan, endothelin-1 and aldosterone. These were associated with significant enhancement of adiponectin, HO-1, HO-activity, cGMP and atrial-natriuretic-peptide (ANP), whereas the HO-inhibitor, chromium-mesoporphyrin nullified the reno-protection and exacerbated renal dysfunction. CONCLUSION AND IMPLICATIONS: Heme-arginate improves renal function by reducing histo-pathological lesions, abating inflammatory/oxidative mediators, attenuating profibrotic/ extracellular-matrix proteins and attenuating albuminuria/ proteinuria, while simultaneously potentiating the HOadiponectin-ANP axis with associated increase in nephrin, podocin, podocalyxin, CD2AP and creatinine clearance.
139 HEME OXYGENASE MODULATES PODOCYTE-ASSOCIATED PROTEINS TO IMPROVE RENAL FUNCTION IN HYPERTENSION
Edmonton, Alberta
J Ndisang BACKGROUND:
Although heme-oxygenase (HO) is cytoprotective, its effects on podocyte proteins like podocalyxin, podocin, CD2-associated protein in renal dysfunction in Nu-nitro-L-arginine-methyl-ester (L-NAME) hypertension are largely unclear. EXPERIMENTAL APPROACH: Hypertension was induced in healthy Sprague-Dawley rats via the administration of L-NAME for 4 weeks. HO was enhanced with heme-arginate or inhibited with chromium-mesoporphyrin and several assays including Enzyme-immunoassay, ELISA, histology/morphology, spectrophotometry and Western-immunoblotting were used. RESULTS: Treatment with heme-arginate reduced several kidney histo-pathological lesions including, tubular-atrophy/ fibrosis, glomerular abnormalities, renal-arteriolar thickening, tubular-cast and mononuclear cell-infiltration in L-NAMEhypertensive rats. In addition, heme-arginate abated the elevated levels of renal extracellular-matrix/pro-fibrotic proteins like collagen and fibronectin that deplete nephrin, an important trans-membrane protein critical for the formation of the scaffoldings of the podocyte slit-diaphragm that allows small ions to filter, but not massive excretion of proteins, hence proteinuria.
140 A RANDOMIZED TRIAL OF THE EFFECT OF PHARMACIST PRESCRIBING ON IMPROVING BLOOD PRESSURE IN THE COMMUNITY: THE ALBERTA CLINICAL TRIAL IN OPTIMIZING HYPERTENSION (RXACTION) RT Tsuyuki, SK Houle, T Charrois, M Kolber, MM Rosenthal, RZ Lewanczuk, D Cooney, FA McAlister BACKGROUND:
Hypertension control rates in Canada remain suboptimal. In Alberta, pharmacists may apply for Additional Prescribing Authorization, allowing them to prescribe drug therapy for patients. This provides a new option for improving access to hypertension care. The objective of this study was to determine the impact of pharmacist care (including prescribing) on systolic blood pressure (SBP) in patients with uncontrolled hypertension. METHODS: DESIGN: Randomized controlled trial with patients as the unit of randomization, with care provided by 22 Alberta pharmacists with prescribing authorization. PATIENTS: Adults with BP above recommended targets (>140/90 or >130/ 80mmHg if diabetic) based upon measurements over multiple visits. Enhanced Care: Pharmacist assessment, BP wallet card, education on hypertension, pharmacist prescribing of antihypertensive drugs and laboratory monitoring using current Canadian guidelines, and monthly follow-up visits dropping down to every 3 months if target BP was achieved for 2 consecutive visits. All patients were followed for 6 months. CONTROL: Wallet card for BP recording, patient information materials on hypertension, and no study specific follow-up. Outcomes: Primary outcome was the difference in change in systolic BP between the intervention and control groups at 6 months. RESULTS: A total of 248 patients were randomized to the study. The mean (SD) patient age was 63.5 (12.7) years,