Tawar Qaradakhi1, Minos Timotheos Matsoukas2, Alan Hayes1, Emma Rybalka1, Martin Caprnda3, Kvetoslava Rimarova4, Milan Sepsi5, Dietrich Büsselberg6, Peter Kruzliak7, John Matsoukas8, Vasso Apostolopoulos1, Anthony Zulli1. 1. Centre for Chronic Disease, College of Health and Biomedicine, Victoria University, Melbourne, Vic., Australia. 2. Department of Pharmacy, University of Patras, Patras, Greece. 3. 2nd Department of Internal Medicine, Faculty of Medicine, Comenius University, Bratislava, Slovakia. 4. Department of Public Health and Hygiene, Faculty of Medicine, Pavol Jozef Safarik University, Kosice, Slovakia. 5. Department of Internal Medicine and Cardiology, University Hospital, Brno, Czech Republic. 6. Department of Physiology and Biophysics, Weill Cornell Medical College in Qatar, Qatar Foundation - Education City, Doha, Qatar. 7. Department of Chemical Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic. 8. ELdrug SA, Patras Science Park, Patras, Greece.
Abstract
INTRODUCTION: Hyperhomocysteinemia (HHcy) impairs nitric oxide endothelium-dependent vasodilation, consequently leading to atherosclerosis, a risk factor for cardiovascular disease. Novel treatments for HHcy are necessary. AIM: We tested the hypothesis that alamandine, a vasoactive peptide of the renin-angiotensin system (RAS), could reverse HHcy-induced vascular dysfunction through the MrgD receptor and that this is mediated by the protein kinase A (PKA) pathway. Furthermore, we sought to determine a putative binding model of alamandine to the MrgD receptor through docking and molecular dynamics simulations. METHOD: The abdominal aorta was excised from New Zealand white rabbits (n = 15) and incubated with 3 mmol/L Hcy (to mimic HHcy) to induce vascular dysfunction in vitro. Vascular function was assessed by vasodilatory responses to cumulative doses of acetylcholine. RESULT: Vasodilation was significantly impaired in HHcy-incubated aortic rings while alamandine reversed this effect (control, 74.2 ± 5.0%; Hcy, 30.3 ± 9.8%; alamandine + Hcy, 59.7 ± 4.8%, P < .0001). KT5720 (PKA inhibitor) significantly inhibited the ability of alamandine to attenuate the impaired vasodilation caused by HHcy (KT5720 + Hcy + alamandine, 27.1 ± 24.1, P < .01). Following immunohistochemistry analysis, the MrgD receptor was highly expressed within the media and endothelial layer of aortic rings in HHcy compared to control (media: 0.23 ± 0.003 vs control 0.16 ± 0.01, P < .05 and endothelium: 0.68 ± 0.07 vs control 0.13 ± 0.02, P < .01, in PA/I (A.U) units). Computational studies also propose certain interactions of alamandine within the MrgD transmembrane domain. CONCLUSION: This study shows that alamandine is effective in reversing HHcy-induced vascular dysfunction, possibly through the PKA signaling pathway via MrgD. Our results indicate a therapeutic potential of alamandine in reversing the detrimental effects of HHcy.
INTRODUCTION:Hyperhomocysteinemia (HHcy) impairs nitric oxide endothelium-dependent vasodilation, consequently leading to atherosclerosis, a risk factor for cardiovascular disease. Novel treatments for HHcy are necessary. AIM: We tested the hypothesis that alamandine, a vasoactive peptide of the renin-angiotensin system (RAS), could reverse HHcy-induced vascular dysfunction through the MrgD receptor and that this is mediated by the protein kinase A (PKA) pathway. Furthermore, we sought to determine a putative binding model of alamandine to the MrgD receptor through docking and molecular dynamics simulations. METHOD: The abdominal aorta was excised from New Zealand white rabbits (n = 15) and incubated with 3 mmol/L Hcy (to mimic HHcy) to induce vascular dysfunction in vitro. Vascular function was assessed by vasodilatory responses to cumulative doses of acetylcholine. RESULT: Vasodilation was significantly impaired in HHcy-incubated aortic rings while alamandine reversed this effect (control, 74.2 ± 5.0%; Hcy, 30.3 ± 9.8%; alamandine + Hcy, 59.7 ± 4.8%, P < .0001). KT5720 (PKA inhibitor) significantly inhibited the ability of alamandine to attenuate the impaired vasodilation caused by HHcy (KT5720 + Hcy + alamandine, 27.1 ± 24.1, P < .01). Following immunohistochemistry analysis, the MrgD receptor was highly expressed within the media and endothelial layer of aortic rings in HHcy compared to control (media: 0.23 ± 0.003 vs control 0.16 ± 0.01, P < .05 and endothelium: 0.68 ± 0.07 vs control 0.13 ± 0.02, P < .01, in PA/I (A.U) units). Computational studies also propose certain interactions of alamandine within the MrgD transmembrane domain. CONCLUSION: This study shows that alamandine is effective in reversing HHcy-induced vascular dysfunction, possibly through the PKA signaling pathway via MrgD. Our results indicate a therapeutic potential of alamandine in reversing the detrimental effects of HHcy.
Authors: Anahi Guadalupe Figueroa-Torres; Lisneth Osiris Matias-Aguilar; Erika Coria-Ramirez; Edmundo Bonilla-Gonzalez; Humberto Gonzalez-Marquez; Isabel Ibarra-Gonzalez; Jose Rubicel Hernandez-Lopez; Jesus Hernandez-Juarez; Victor Manuel Dominguez-Reyes; Irma Isordia-Salas; Abraham Majluf-Cruz Journal: SAGE Open Med Date: 2020-11-20