keyword
MENU ▼
Read by QxMD icon Read
search

Ryr2

keyword
https://www.readbyqxmd.com/read/28508509/investigating-the-inter-subunit-subdomain-interactions-and-motions-relevant-to-disease-mutations-in-the-n-terminal-domain-of-ryanodine-receptors-by-molecular-dynamics-simulation
#1
Wenjun Zheng, Zheng Liu
The ryanodine receptors (RyR) are essential to calcium signaling in striated muscles, and numerous disease mutations have been identified in two RyR isoforms, RyR1 in skeletal muscle and RyR2 in cardiac muscle. A deep understanding of the activation/regulation mechanisms of RyRs has been hampered by the shortage of high-resolution structures and dynamic information for this giant tetrameric complex in different functional states. Toward elucidating the molecular mechanisms of disease mutations in RyRs, we performed molecular dynamics simulation of the N-terminal domain (NTD) which is not only the best-resolved structural component of RyRs, but also a hotspot of disease mutations...
May 15, 2017: Proteins
https://www.readbyqxmd.com/read/28487634/ryr2-mediated-ca-2-release-and-mitochondrial-ros-generation-partake-in-the-synaptic-dysfunction-caused-by-amyloid-%C3%AE-peptide-oligomers
#2
Carol D SanMartín, Pablo Veloso, Tatiana Adasme, Pedro Lobos, Barbara Bruna, Jose Galaz, Alejandra García, Steffen Hartel, Cecilia Hidalgo, Andrea C Paula-Lima
Amyloid β peptide oligomers (AβOs), toxic aggregates with pivotal roles in Alzheimer's disease, trigger persistent and low magnitude Ca(2+) signals in neurons. We reported previously that these Ca(2+) signals, which arise from Ca(2+) entry and subsequent amplification by Ca(2+) release through ryanodine receptor (RyR) channels, promote mitochondrial network fragmentation and reduce RyR2 expression. Here, we examined if AβOs, by inducing redox sensitive RyR-mediated Ca(2+) release, stimulate mitochondrial Ca(2+)-uptake, ROS generation and mitochondrial fragmentation, and also investigated the effects of the antioxidant N-acetyl cysteine (NAC) and the mitochondrial antioxidant EUK-134 on AβOs-induced mitochondrial dysfunction...
2017: Frontiers in Molecular Neuroscience
https://www.readbyqxmd.com/read/28484388/aging-impairs-hippocampal-dependent-recognition-memory-and-ltp-and-prevents-the-associated-ryr-up-regulation
#3
Alejandra Arias-Cavieres, Tatiana Adasme, Gina Sánchez, Pablo Muñoz, Cecilia Hidalgo
Recognition memory comprises recollection judgment and familiarity, two different processes that engage the hippocampus and the perirhinal cortex, respectively. Previous studies have shown that aged rodents display defective recognition memory and alterations in hippocampal synaptic plasticity. We report here that young rats efficiently performed at short-term (5 min) and long-term (24 h) hippocampus-associated object-location tasks and perirhinal cortex-related novel-object recognition tasks. In contrast, aged rats successfully performed the object-location and the novel-object recognition tasks only at short-term...
2017: Frontiers in Aging Neuroscience
https://www.readbyqxmd.com/read/28476886/amyloid-%C3%AE-production-is-regulated-by-%C3%AE-2-adrenergic-signaling-mediated-post-translational-modifications-of-the-ryanodine-receptor
#4
Renaud Bussiere, Alain Lacampagne, Steven Reiken, Xiaoping Liu, Valerie Scheuerman, Ran Zalk, Cécile Martin, Frederic Checler, Andrew R Marks, Mounia Chami
Alteration of ryanodine receptor (RyR)-mediated calcium (Ca(2+)) signaling has been reported in Alzheimer disease (AD) models. However, the molecular mechanisms underlying altered RyR-mediated intracellular Ca(2+) release in AD remain to be fully elucidated. We report here that RyR2 undergoes post-translational modifications (phosphorylation, oxidation, and nitrosylation) in SH-SY5Y neuroblastoma cells expressing the β-amyloid precursor protein (βAPP) harboring the familial double Swedish mutations (APPswe)...
May 5, 2017: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/28473402/post-myocardial-infarction-t-tubules-form-enlarged-branched-structures-with-dysregulation-of-junctophilin-2-and-bridging-integrator-1-bin-1
#5
Christian Pinali, Nadim Malik, J Bernard Davenport, Laurence J Allan, Lucy Murfitt, Mohammad M Iqbal, Mark R Boyett, Elizabeth J Wright, Rachel Walker, Yu Zhang, Halina Dobryznski, Cathy M Holt, Ashraf Kitmitto
BACKGROUND: Heart failure is a common secondary complication following a myocardial infarction (MI), characterized by impaired cardiac contraction and t-tubule (t-t) loss. However, post-MI nano-scale morphological changes to the remaining t-ts are poorly understood. METHOD AND RESULTS: We utilized a porcine model of MI, using a nonlethal microembolization method to generate controlled microinfarcts. Using serial block face scanning electron microscopy, we report that post-MI, after mild left-ventricular dysfunction has developed, t-ts are not only lost in the peri-infarct region, but also the remnant t-ts form enlarged, highly branched disordered structures, containing a dense intricate inner membrane...
May 4, 2017: Journal of the American Heart Association
https://www.readbyqxmd.com/read/28451724/chronic-loss-of-inhibitor-1-diminishes-cardiac-ryr2-phosphorylation-despite-exaggerated-camkii-activity
#6
Stefan Neef, Jordi Heijman, Kristian Otte, Matthias Dewenter, Ali R Saadatmand, Stefanie Meyer-Roxlau, Christopher L Antos, Johannes Backs, Dobromir Dobrev, Michael Wagner, Lars S Maier, Ali El-Armouche
Inhibitor-1 (I-1) modulates protein phosphatase 1 (PP1) activity and thereby counteracts the phosphorylation by kinases. I-1 is downregulated and deactivated in failing hearts, but whether its role is beneficial or detrimental remains controversial, and opposing therapeutic strategies have been proposed. Overactivity of Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) with hyperphosphorylation of ryanodine receptors (RyR2) at the CaMKII-site is recognized to be central for heart failure and arrhythmias...
April 27, 2017: Naunyn-Schmiedeberg's Archives of Pharmacology
https://www.readbyqxmd.com/read/28449774/utility-of-post-mortem-genetic-testing-in-cases-of-sudden-arrhythmic-death-syndrome
#7
Najim Lahrouchi, Hariharan Raju, Elisabeth M Lodder, Efstathios Papatheodorou, James S Ware, Michael Papadakis, Rafik Tadros, Della Cole, Jonathan R Skinner, Jackie Crawford, Donald R Love, Chee J Pua, Bee Y Soh, Jaydutt D Bhalshankar, Risha Govind, Jacob Tfelt-Hansen, Bo G Winkel, Christian van der Werf, Yanushi D Wijeyeratne, Greg Mellor, Jan Till, Marta C Cohen, Maria Tome-Esteban, Sanjay Sharma, Arthur A M Wilde, Stuart A Cook, Connie R Bezzina, Mary N Sheppard, Elijah R Behr
BACKGROUND: Sudden arrhythmic death syndrome (SADS) describes a sudden death with negative autopsy and toxicological analysis. Cardiac genetic disease is a likely etiology. OBJECTIVES: This study investigated the clinical utility and combined yield of post-mortem genetic testing (molecular autopsy) in cases of SADS and comprehensive clinical evaluation of surviving relatives. METHODS: We evaluated 302 expertly validated SADS cases with suitable DNA (median age: 24 years; 65% males) who underwent next-generation sequencing using an extended panel of 77 primary electrical disorder and cardiomyopathy genes...
May 2, 2017: Journal of the American College of Cardiology
https://www.readbyqxmd.com/read/28445755/mapping-ryanodine-binding-sites-in-the-pore-cavity-of-ryanodine-receptors
#8
Van A Ngo, Laura L Perissinotti, Williams Miranda, S R Wayne Chen, Sergei Y Noskov
Ryanodine (Ryd) irreversibly targets ryanodine receptors (RyRs), a family of intracellular calcium release channels essential for many cellular processes ranging from muscle contraction to learning and memory. Little is known of the atomistic details about how Ryd binds to RyRs. In this study, we used all-atom molecular dynamics simulations with both enhanced and bidirectional sampling to gain direct insights into how Ryd interacts with major residues in RyRs that were experimentally determined to be critical for its binding...
April 25, 2017: Biophysical Journal
https://www.readbyqxmd.com/read/28428008/force-development-and-intracellular-ca-2-in-intact-cardiac-muscles-from-gravin-mutant-mice
#9
Zhitao Li, Sonal Singh, Santosh V Suryavanshi, Wengang Ding, Xiaoxu Shen, Cori S Wijaya, Wei Dong Gao, Bradley K McConnell
Gravin (AKAP12) is an A-kinase-anchoring-protein that scaffolds protein kinase A (PKA), β2-adrenergic receptor (β2-AR), protein phosphatase 2B and protein kinase C. Gravin facilitates β2-AR-dependent signal transduction through PKA to modulate cardiac excitation-contraction coupling and its removal positively affects cardiac contraction. Trabeculae from the right ventricles of gravin mutant (gravin-t/t) mice were employed for force determination. Simultaneously, corresponding intracellular Ca(2+) transient ([Ca(2+)]i) were measured...
April 17, 2017: European Journal of Pharmacology
https://www.readbyqxmd.com/read/28422759/ryr2r420q-catecholaminergic-polymorphic-ventricular-tachycardia-mutation-induces-bradycardia-by-disturbing-the-coupled-clock-pacemaker-mechanism
#10
Yue Yi Wang, Pietro Mesirca, Elena Marqués-Sulé, Alexandra Zahradnikova, Olivier Villejoubert, Pilar D'Ocon, Cristina Ruiz, Diana Domingo, Esther Zorio, Matteo E Mangoni, Jean-Pierre Benitah, Ana María Gómez
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a lethal genetic arrhythmia that manifests syncope or sudden death in children and young adults under stress conditions. CPVT patients often present bradycardia and sino-atrial node (SAN) dysfunction. However, the mechanism remains unclear. We analyzed SAN function in two CPVT families and in a novel knock-in (KI) mouse model carrying the RyR2R420Q mutation. Humans and KI mice presented slower resting heart rate. Accordingly, the rate of spontaneous intracellular Ca2+ ([Ca2+]i) transients was slower in KI mouse SAN preparations than in WT, without any significant alteration in the "funny" current (If )...
April 20, 2017: JCI Insight
https://www.readbyqxmd.com/read/28405885/sudden-death-due-to-catecholaminergic-polymorphic-ventricular-tachycardia-following-negative-stress-test-outcome-genetics-and-clinical-implications
#11
Cristian D'Ovidio, Aldo Carnevale, Vincenzo M Grassi, Enrica Rosato, Bernat Del Olmo, Monica Coll, Oscar Campuzano, Anna Iglesias, Ramon Brugada, Antonio Oliva
This paper discusses the case of a young boy who died suddenly during a football match. The victim's personal and family medical histories were negative for cardiac events. He had undergone a cardiological investigation some months before his death, enabling him to participate in competitive sports. Only post-mortem molecular analysis allowed for a clearer determination of the most plausible cause of death, which was identified as inherited arrhythmogenic heart disease, known as catecholaminergic polymorphic ventricular tachycardia...
April 13, 2017: Forensic Science, Medicine, and Pathology
https://www.readbyqxmd.com/read/28404607/interpreting-incidentally-identified-variants-in-genes-associated-with-catecholaminergic-polymorphic-ventricular-tachycardia-in-a-large-cohort-of-clinical-whole-exome-genetic-test-referrals
#12
Andrew P Landstrom, Andrew L Dailey-Schwartz, Jill A Rosenfeld, Yaping Yang, Margaret J McLean, Christina Y Miyake, Santiago O Valdes, Yuxin Fan, Hugh D Allen, Daniel J Penny, Jeffrey J Kim
BACKGROUND: The rapid expansion of genetic testing has led to increased utilization of clinical whole-exome sequencing (WES). Clinicians and genetic researchers are being faced with assessing risk of disease vulnerability from incidentally identified genetic variants which is typified by variants found in genes associated with sudden death-predisposing catecholaminergic polymorphic ventricular tachycardia (CPVT). We sought to determine whether incidentally identified variants in genes associated with CPVT from WES clinical testing represent disease-associated biomarkers...
April 2017: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/28389603/the-impact-of-ryr2-potentiation-on-myocardial-function
#13
Elena Lascano, Jorge A Negroni, Martin Vila Petroff, Alicia Mattiazzi
This perspective attempts to shed light on an old and not yet solved controversy in cardiac physiology, i.e. the impact of increasing RyR2 open probability on myocardial function. Based on an already proved myocyte model, it is shown that increasing RyR2 open probability results in a purely short-lived increase in Ca(2+) transient amplitude, and therefore it does not increase cardiac contractility. However, potentiation of RyR2 activity permanently enhances fractional Ca(2+) release, shifting the intracellular Ca(2+) transient vs SR Ca(2+) content curve to a new state of higher efficiency...
April 7, 2017: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/28374413/beneficial-effects-of-leptin-treatment-in-a-setting-of-cardiac-dysfunction-induced-by-transverse-aortic-constriction-in-mouse
#14
Nieves Gómez-Hurtado, Alejandro Domínguez-Rodríguez, Philippe Mateo, Maria Fernandez-Velasco, Almudena Val-Blasco, Rafael Aizpún, Jessica Sabourin, Ana Maria Gómez, Jean-Pierre Benitah, Carmen Delgado
KEY POINTS: Leptin, is a 16 kDa pleiotropic peptide, primary secreted by adipocytes, but also produced by other tissues including the heart. Controversy exists regarding the adverse and beneficial effects of Leptin on the heart We analysed the effect of a non-hypertensive dose of leptin on cardiac function, [Ca(2+) ]i handling and cellular electrophysiology, which participate in the genesis of pump failure and related arrhythmias both in control mice and in mice subjected to chronic pressure-overload by transverse aorta constriction We find that Leptin activates mechanisms that contribute to cardiac dysfunction in physiological conditions...
April 4, 2017: Journal of Physiology
https://www.readbyqxmd.com/read/28370799/through-modulation-of-cardiac-ca-2-handling-ucp2-affects-cardiac-electrophysiology-and-influences-the-susceptibility-for-ca-2-mediated-arrhythmias
#15
Robert Larbig, Sara Reda, Vera Paar, Andrea Trost, Johannes Leitner, Stephanie Weichselbaumer, Karolina A Motloch, Bernhard Wernly, Andreas Arrer, Benjamin Strauss, Michael Lichtenauer, Herbert A Reitsamer, Lars Eckardt, Guiscard Seebohm, Uta C Hoppe, Lukas J Motloch
Introduction UCP2 belongs to a superfamily of mitochondrial ion transporters. Due to its beneficial influence on production of reactive oxygen species it is suggested to reduce cardiac ischemic reperfusion injury. Recent studies uncovered its ability to regulate mitochondrial Ca(2+) -uptake and therefore to influence cardiac cytosolic Ca(2+) -handling, indicating compensatory pathways to avoid toxic Ca(2+) -overload in UCP2 knock-out mice (UCP2(-/-) ). However, the specific mechanisms and their impact on cardiac electrophysiology remain speculative...
March 31, 2017: Experimental Physiology
https://www.readbyqxmd.com/read/28369767/multiple-targets-for-flecainide-action-implications-for-cardiac-arrhythmogenesis
#16
REVIEW
Samantha C Salvage, Karthik H Chandrasekharan, Kamalan Jeevaratnam, Angela F Dulhunty, Andrew J Thompson, Antony P Jackson, Christopher L-H Huang
Flecainide suppresses cardiac tachyarrhythmias including paroxysmal atrial fibrillation, supraventricular tachycardia and arrhythmic long QT syndromes (LQTS), as well as the Ca(2+) -mediated, catecholaminergic polymorphic ventricular tachycardia (CPVT). However, flecainide can also exert pro-arrhythmic effects most notably following myocardial infarction and when used to diagnose Brugada syndrome (BrS). These divergent actions result from its physiological and pharmacological actions at multiple, interacting levels of cellular organization...
April 3, 2017: British Journal of Pharmacology
https://www.readbyqxmd.com/read/28359509/autosomal-recessive-cardiomyopathy-presenting-as-acute-myocarditis
#17
Serkan Belkaya, Amy R Kontorovich, Minji Byun, Sonia Mulero-Navarro, Fanny Bajolle, Aurelie Cobat, Rebecca Josowitz, Yuval Itan, Raphaelle Quint, Lazaro Lorenzo, Soraya Boucherit, Cecile Stoven, Sylvie Di Filippo, Laurent Abel, Shen-Ying Zhang, Damien Bonnet, Bruce D Gelb, Jean-Laurent Casanova
BACKGROUND: Myocarditis is inflammation of the heart muscle that can follow various viral infections. Why children only rarely develop life-threatening acute viral myocarditis (AVM), given that the causal viral infections are common, is unknown. Genetic lesions might underlie such susceptibilities. Mouse genetic studies demonstrated that interferon (IFN)-α/β immunity defects increased susceptibility to virus-induced myocarditis. Moreover, variations in human TLR3, a potent inducer of IFNs, were proposed to underlie AVM...
April 4, 2017: Journal of the American College of Cardiology
https://www.readbyqxmd.com/read/28356340/analysis-of-cardiac-myocyte-maturation-using-casaav-a-platform-for-rapid-dissection-of-cardiac-myocyte-gene-function-in-vivo
#18
Yuxuan Guo, Nathan J VanDusen, Lina Zhang, Weiliang Gu, Isha Sethi, Silvia Guatimosim, Qing Ma, Blake D Jardin, Yulan Ai, Donghui Zhang, Biyi Chen, Ang Guo, Guo-Cheng Yuan, Long-Sheng Song, William T Pu
Rationale: Loss-of-function studies in cardiac myocytes (CMs) are currently limited by the need for appropriate conditional knockout alleles. The factors that regulate CM maturation are poorly understood. Prior studies on CM maturation have been confounded by heart dysfunction caused by whole organ gene inactivation. Objective: To develop a new technical platform to rapidly characterize cell-autonomous gene function in postnatal murine CMs and apply it to identify genes that regulate T-tubules, a hallmark of mature cardiac myocytes...
March 29, 2017: Circulation Research
https://www.readbyqxmd.com/read/28349937/biodegradable-polymeric-nanocapsules-prevent-cardiotoxicity-of-anti-trypanosomal-lychnopholide
#19
Renata Tupinambá Branquinho, Jérôme Roy, Charlotte Farah, Giani Martins Garcia, Franck Aimond, Jean-Yves Le Guennec, Dênia Antunes Saude-Guimarães, Andrea Grabe-Guimaraes, Vanessa Carla Furtado Mosqueira, Marta de Lana, Sylvain Richard
Chagas disease is a neglected parasitic disease caused by the protozoan Trypanosoma cruzi. New antitrypanosomal options are desirable to prevent complications, including a high rate of cardiomyopathy. Recently, a natural substance, lychnopholide, has shown therapeutic potential, especially when encapsulated in biodegradable polymeric nanocapsules. However, little is known regarding possible adverse effects of lychnopholide. Here we show that repeated-dose intravenous administration of free lychnopholide (2...
March 28, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28332202/calcium-signalling-silencing-in-atrial-fibrillation
#20
Maura Greiser
Subcellular calcium signalling silencing is a novel and distinct cellular and molecular adaptive response to rapid cardiac activation. Calcium signalling silencing develops during short-term sustained rapid atrial activation as seen clinically during paroxysmal atrial fibrillation (AF). It is the first 'anti-arrhythmic' adaptive response in the setting of AF and appears to counteract the maladaptive changes that lead to intracellular Ca(2+) signalling instability and Ca(2+) -based arrhythmogenicity. Calcium signalling silencing results in a failed propagation of the [Ca(2+) ]i signal to the myocyte centre both in patients with AF and in a rabbit model...
March 22, 2017: Journal of Physiology
keyword
keyword
64280
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"