keyword
MENU ▼
Read by QxMD icon Read
search

Sarcoplasmic reticulum

keyword
https://www.readbyqxmd.com/read/28102477/potential-new-mechanisms-of-pro-arrhythmia-in-arrhythmogenic-cardiomyopathy-focus-on-calcium-sensitive-pathways
#1
REVIEW
C J M van Opbergen, M Delmar, T A B van Veen
Arrhythmogenic cardiomyopathy, or its most well-known subform arrhythmogenic right ventricular cardiomyopathy (ARVC), is a cardiac disease mainly characterised by a gradual replacement of the myocardial mass by fibrous and fatty tissue, leading to dilatation of the ventricular wall, arrhythmias and progression towards heart failure. ARVC is commonly regarded as a disease of the intercalated disk in which mutations in desmosomal proteins are an important causative factor. Interestingly, the Dutch founder mutation PLN R14Del has been identified to play an additional, and major, role in ARVC patients within the Netherlands...
January 19, 2017: Netherlands Heart Journal
https://www.readbyqxmd.com/read/28096415/increased-mitochondrial-nanotunneling-activity-induced-by-calcium-imbalance-affects-intermitochondrial-matrix-exchanges
#2
Manuela Lavorato, V Ramesh Iyer, Williams Dewight, Ryan R Cupo, Valentina Debattisti, Ludovic Gomez, Sergio De la Fuente, Yan-Ting Zhao, Héctor H Valdivia, György Hajnóczky, Clara Franzini-Armstrong
Exchanges of matrix contents are essential to the maintenance of mitochondria. Cardiac mitochondrial exchange matrix content in two ways: by direct contact with neighboring mitochondria and over longer distances. The latter mode is supported by thin tubular protrusions, called nanotunnels, that contact other mitochondria at relatively long distances. Here, we report that cardiac myocytes of heterozygous mice carrying a catecholaminergic polymorphic ventricular tachycardia-linked RyR2 mutation (A4860G) show a unique and unusual mitochondrial response: a significantly increased frequency of nanotunnel extensions...
January 17, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28094777/high-resolution-structural-evidence-suggests-the-sarcoplasmic-reticulum-forms-microdomains-with-acidic-stores-lysosomes-in-the-heart
#3
Daniel Aston, Rebecca A Capel, Kerrie L Ford, Helen C Christian, Gary R Mirams, Eva A Rog-Zielinska, Peter Kohl, Antony Galione, Rebecca A B Burton, Derek A Terrar
Nicotinic Acid Adenine Dinucleotide Phosphate (NAADP) stimulates calcium release from acidic stores such as lysosomes and is a highly potent calcium-mobilising second messenger. NAADP plays an important role in calcium signalling in the heart under basal conditions and following β-adrenergic stress. Nevertheless, the spatial interaction of acidic stores with other parts of the calcium signalling apparatus in cardiac myocytes is unknown. We present evidence that lysosomes are intimately associated with the sarcoplasmic reticulum (SR) in ventricular myocytes; a median separation of 20 nm in 2D electron microscopy and 3...
January 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28093226/conformational-transitions-and-alternating-access-mechanism-in-the-sarcoplasmic-reticulum-calcium-pump
#4
Avisek Das, Huan Rui, Robert Nakamoto, Benoît Roux
Ion pumps are integral membrane proteins responsible for transporting ions against concentration gradients across biological membranes. Sarco/endoplasmic reticulum Ca(2+)-ATPase (SERCA), a member of the P-type ATPases family, transports two calcium ions per hydrolyzed ATP molecule via an "alternating-access" mechanism. High-resolution crystallographic structures provide invaluable insight on the structural mechanism of the ion pumping process. However, to understand the molecular details of how ATP hydrolysis is coupled to calcium transport, it is necessary to gain knowledge about the conformational transition pathways connecting the crystallographically resolved conformations...
January 13, 2017: Journal of Molecular Biology
https://www.readbyqxmd.com/read/28079567/cardiac-calcium-release-channel-ryanodine-receptor-2-regulation-by-halogenated-anesthetics
#5
Derek R Laver, John Attia, Christopher Oldmeadow, Anthony W Quail
BACKGROUND: Halogenated anesthetics activate cardiac ryanodine receptor 2-mediated sarcoplasmic reticulum Ca release, leading to sarcoplasmic reticulum Ca depletion, reduced cardiac function, and providing cell protection against ischemia-reperfusion injury. Anesthetic activation of ryanodine receptor 2 is poorly defined, leaving aspects of the protective mechanism uncertain. METHODS: Ryanodine receptor 2 from the sheep heart was incorporated into artificial lipid bilayers, and their gating properties were measured in response to five halogenated anesthetics...
January 12, 2017: Anesthesiology
https://www.readbyqxmd.com/read/28069951/calsequestrin-depolymerizes-when-calcium-is-depleted-in-the-sarcoplasmic-reticulum-of-working-muscle
#6
Carlo Manno, Lourdes C Figueroa, Dirk Gillespie, Robert Fitts, ChulHee Kang, Clara Franzini-Armstrong, Eduardo Rios
Calsequestrin, the only known protein with cyclical storage and supply of calcium as main role, is proposed to have other functions, which remain unproven. Voluntary movement and the heart beat require this calcium flow to be massive and fast. How does calsequestrin do it? To bind large amounts of calcium in vitro, calsequestrin must polymerize and then depolymerize to release it. Does this rule apply inside the sarcoplasmic reticulum (SR) of a working cell? We answered using fluorescently tagged calsequestrin expressed in muscles of mice...
January 9, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28062939/early-transverse-tubule-development-begins-in-utero-in-the-sheep-heart
#7
Michelle L Munro, Christian Soeller
The ventricular cardiomyocytes of adult mammals contain invaginations of the plasma membrane known as transverse (t)-tubules. These regular structures are essential for the synchronisation of excitation-contraction (EC) coupling throughout the cell, which is a vital process for cardiac function. T-tubules form a close association with the sarcoplasmic reticulum (SR) to form junctions, where several key proteins involved in EC coupling are localised, including the SR calcium release channels-the ryanodine receptors (RyR)...
January 6, 2017: Journal of Muscle Research and Cell Motility
https://www.readbyqxmd.com/read/28031099/low-dose-simvastatin-increases-skeletal-muscle-sensitivity-to-caffeine-and-halothane
#8
Xu-Lei Cui, Ying-Lin Wang, Gang Tan, Ai-Lun Luo, Xiang-Yang Guo
Objective To determine whether the myotoxic side effects of statin simvastatin affect skeletal muscle's sensitivity to caffeine and halothane.Methods Primary cultured neonate rat skeletal myotubes were treated with 0.01-5.0 μmol/L simvastatin for 48 hours. MTT was used to evaluate cellular viability. The gross morphology and microstructure of the myotubes were observed with a light and electron microscope, respectively. The intracellular calcium concentrations ([Ca(2+)]i) at rest and in response to caffeine and halothane were investigated by fluorescence calcium imaging...
June 20, 2016: Chinese Medical Sciences Journal, Chung-kuo i Hsüeh K'o Hsüeh Tsa Chih
https://www.readbyqxmd.com/read/28028837/a-novel-mechanism-of-tandem-activation-of-ryanodine-receptors-by-cytosolic-and-sr-luminal-ca-during-excitation-contraction-coupling-in-atrial-myocytes
#9
Joshua T Maxwell, Lothar A Blatter
In atrial myocytes Ca release during excitation-contraction coupling (ECC) is strikingly different from ventricular myocytes. In many species atrial myocytes lack a transverse tubule system, dividing the sarcoplasmic reticulum (SR) Ca store into the peripheral subsarcolemmnal junctional (j-SR) and the much more abundant central non-junctional (nj-SR) SR. Action potential (AP)-induced Ca entry activates Ca-induced Ca release (CICR) from j-SR ryanodine receptor (RyR) Ca release channels. Peripheral elevation of [Ca]i initiates CICR from nj-SR and sustains propagation of CICR to the cell centre...
December 28, 2016: Journal of Physiology
https://www.readbyqxmd.com/read/28017135/role-of-sumoylation-in-heart-development-and-cardiovascular-diseases
#10
L Zhang, T-H Yang, D W-C Li
Heart is an extremely important organ, and cardiovascular disorders emerge as primary life-threatening disease in human life. Aberrant post-translational modifications (PTMs) on cardiac proteins are closely correlated with pathological abnormalities in heart. SUMOylation, one of the most prevalent PTMs with thousands of substrates throughout the cell including critical subcellular organelles, has been shown to precisely fine-tune the cell survival and proliferation during heart development, and delicately control the function of mitochondrion and sarcoplasmic reticulum in physiological heart functioning...
December 23, 2016: Current Molecular Medicine
https://www.readbyqxmd.com/read/28012042/dihydropyridine-receptor-dhpr-cacna1s-congenital-myopathy
#11
Vanessa Schartner, Norma B Romero, Sandra Donkervoort, Susan Treves, Pinki Munot, Tyler Mark Pierson, Ivana Dabaj, Edoardo Malfatti, Irina T Zaharieva, Francesco Zorzato, Osorio Abath Neto, Guy Brochier, Xavière Lornage, Bruno Eymard, Ana Lía Taratuto, Johann Böhm, Hernan Gonorazky, Leigh Ramos-Platt, Lucy Feng, Rahul Phadke, Diana X Bharucha-Goebel, Charlotte Jane Sumner, Mai Thao Bui, Emmanuelle Lacene, Maud Beuvin, Clémence Labasse, Nicolas Dondaine, Raphael Schneider, Julie Thompson, Anne Boland, Jean-François Deleuze, Emma Matthews, Aleksandra Nadaj Pakleza, Caroline A Sewry, Valérie Biancalana, Susana Quijano-Roy, Francesco Muntoni, Michel Fardeau, Carsten G Bönnemann, Jocelyn Laporte
Muscle contraction upon nerve stimulation relies on excitation-contraction coupling (ECC) to promote the rapid and generalized release of calcium within myofibers. In skeletal muscle, ECC is performed by the direct coupling of a voltage-gated L-type Ca(2+) channel (dihydropyridine receptor; DHPR) located on the T-tubule with a Ca(2+) release channel (ryanodine receptor; RYR1) on the sarcoplasmic reticulum (SR) component of the triad. Here, we characterize a novel class of congenital myopathy at the morphological, molecular, and functional levels...
December 23, 2016: Acta Neuropathologica
https://www.readbyqxmd.com/read/28008615/mn-2-transport-by-ca-2-atpase-of-sarcoplasmic-reticulum
#12
Shin-Ichiro Yonekura, Chikashi Toyoshima
No abstract text is available yet for this article.
December 2016: FEBS Letters
https://www.readbyqxmd.com/read/28007605/mitochondrial-networking-in-diabetic-left-ventricle-cardiomyocytes
#13
REVIEW
Lucia-Doina Popov
Cardiomyocyte mitochondria preserve "the quorum sensing" attribute of their aerobic bacterial ancestors, as shown by the transient physical connectivity and communication not only with each other, but also with other intracellular organelles and with cytosol, ensuing cellular homeostasis. In this review, we present original electron microscopy evidence on mitochondrial networking within diabetic left ventricular cardiomyocytes, focusing on: (i) the inter-mitochondrial communication, allowing electrochemical signals transfer and outer membrane components or matrix proteins exchange, (ii) the interplay between mitochondria and the cardiomyocyte nucleus, nucleolus, sarcoplasmic reticulum, lysosomes, and lipid droplets viewed as attributes of mitochondrial "quality control" and "retrograde signaling function", and (iii) the crosstalk between mitochondria and cardiomyocyte cytosol, as part of the adaptive responses that allow cells survival...
December 19, 2016: Mitochondrion
https://www.readbyqxmd.com/read/28003463/congenital-myopathy-results-from-misregulation-of-a-muscle-ca2-channel-by-mutant-stac3
#14
Jeremy W Linsley, I-Uen Hsu, Linda Groom, Viktor Yarotskyy, Manuela Lavorato, Eric J Horstick, Drew Linsley, Wenjia Wang, Clara Franzini-Armstrong, Robert T Dirksen, John Y Kuwada
Skeletal muscle contractions are initiated by an increase in Ca(2+) released during excitation-contraction (EC) coupling, and defects in EC coupling are associated with human myopathies. EC coupling requires communication between voltage-sensing dihydropyridine receptors (DHPRs) in transverse tubule membrane and Ca(2+) release channel ryanodine receptor 1 (RyR1) in the sarcoplasmic reticulum (SR). Stac3 protein (SH3 and cysteine-rich domain 3) is an essential component of the EC coupling apparatus and a mutation in human STAC3 causes the debilitating Native American myopathy (NAM), but the nature of how Stac3 acts on the DHPR and/or RyR1 is unknown...
December 21, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27998200/spinal-cord-injury-leads-to-hyperoxidation-and-nitrosylation-of-skeletal-muscle-ryanodine-receptor-1-associated-with-upregulation-of-nadh-oxidase-4
#15
Xin-Hua Liu, Lauren Harlow, Zachary A Graham, William A Bauman, Chris Cardozo
Spinal cord injury (SCI) results in marked atrophy and dysfunction of skeletal muscle. There are currently no effective treatments for SCI-induced muscle atrophy or the dysfunction of the remaining muscle tissue. NADPH oxidase-4 (Nox4) produces reactive oxygen species (ROS) in sarcoplasmic reticulum (SR) and has been identified as an important O2 sensor in skeletal muscle. Ryanodine receptors (RyRs) are calcium (Ca2+) channels that are responsible for Ca2+ release from SR. In skeletal muscle, type1 RyR (RyR1) is predominantly functional...
December 21, 2016: Journal of Neurotrauma
https://www.readbyqxmd.com/read/27995745/towards-an-integrated-understanding-of-cardiac-arrhythmogenesis-growing-roles-of-experimental-pathology
#16
REVIEW
Hideo Tanaka, Taka-Aki Matsuyama, Tetsuro Takamatsu
Cardiac arrhythmias have long been regarded as derangement of electrical impulse initiation and conduction within the heart. However, underlying mechanisms for arrhythmogenesis are not fully understood solely from the electrophysiological viewpoint. This review article discusses pathogenesis of arrhythmias from non-electrical aspects, which were elucidated by spatiotemporal imaging of functional molecules in combination with morphological analysis of living heart tissues. Intracellular Ca(2+) ([Ca(2+) ]i ) overload, caused by myocardial injury, provokes Ca(2+) waves that could lead to abnormal excitations, i...
January 2017: Pathology International
https://www.readbyqxmd.com/read/27992596/phospholamban-ablation-using-crispr-cas9-system-improves-mortality-in-a-murine-heart-failure-model
#17
Manami Kaneko, Kentarou Hashikami, Satoshi Yamamoto, Hirokazu Matsumoto, Tomoyuki Nishimoto
Sarcoplasmic reticulum Ca2+-ATPase 2a (SERCA2a) and its inhibitory protein called phospholamban (PLN) are pivotal for Ca2+ handling in cardiomyocyte and are known that their expression level and activity were changed in the heart failure patients. To examine whether PLN inhibition can improve survival rate as well as cardiac function in heart failure, we performed PLN ablation in calsequestrin overexpressing (CSQ-Tg) mice, a severe heart failure model, using clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated (Cas) system...
2016: PloS One
https://www.readbyqxmd.com/read/27987400/an-insertion-deletion-polymorphism-within-3-utr-of-ryr2-modulates-sudden-unexplained-death-risk-in-chinese-populations
#18
Shouyu Wang, Zhixiang Zhang, Ya Yang, Chaoqun Wang, Ruiyang Tao, Shuxiang Hu, Zhixia Yin, Qing Zhang, Lijuan Li, Yan He, Shaohua Zhu, Chengtao Li, Suhua Zhang, Jianhua Zhang, Lihui Sheng, Fangyu Wu, Bin Luo, Yuzhen Gao
Sudden unexplained death (SUD) constitutes a part of the overall sudden death that can not be underestimated. Over the last years, genetic testing on SUD has revealed that inherited channelopathies might play important roles in the pathophysiology of this disease. Ryanodine receptor type-2 (RYR2) is a kind of ion channel extensively distributed in the sarcoplasmic reticulum (SR) of myocardium. Studies on RYR2 have suggested that either dysfunction or abnormal expression of it could lead to arrhythmia, which may cause cardiac arrest...
December 9, 2016: Forensic Science International
https://www.readbyqxmd.com/read/27979982/role-of-calpain-in-eccentric-contraction-induced-proteolysis-of-ca2-regulatory-proteins-and-force-depression-in-rat-fast-twitch-skeletal-muscle
#19
Keita Kanzaki, Daiki Watanabe, Mai Kuratani, Takashi Yamada, Satoshi Matsunaga, Masanobu Wada
The aim of this study was to examine the in vivo effects of eccentric contraction (ECC) on calpain-dependent proteolysis of Ca(2+)-regulatory proteins and force production in fast-twitch skeletal muscles. Rat extensor digitorum longus muscles were exposed to 200-repeated ECC in situ and excised immediately (recovery 0) or 3 days (recovery 3) after cessation of ECC. Calpain inhibitor (CI)-treated rats were intraperitoneally injected with MDL-28170 before ECC and during 3 days of recovery. Tetanic force was markedly reduced at recovery 0 and remained reduced at recovery 3...
December 15, 2016: Journal of Applied Physiology
https://www.readbyqxmd.com/read/27966586/pleiotropic-effects-of-myocardial-mmp-9-inhibition-to-prevent-ventricular-arrhythmia
#20
Ching-Hui Weng, Fa-Po Chung, Yao-Chang Chen, Shien-Fong Lin, Po-Hsun Huang, Terry B J Kuo, Wei-Hsuan Hsu, Wen-Cheng Su, Yen-Ling Sung, Yenn-Jiang Lin, Shih-Lin Chang, Li-Wei Lo, Hung-I Yeh, Yi-Jen Chen, Yi-Ren Hong, Shih-Ann Chen, Yu-Feng Hu
Observational studies have established a strong association between matrix metalloproteinase-9 (MMP-9) and ventricular arrhythmia. However, whether MMP-9 has a causal link to ventricular arrhythmia, as well as the underlying mechanism, remains unclear. Here, we investigated the mechanistic involvement of myocardial MMP-9 in the pathophysiology of ventricular arrhythmia. Increased levels of myocardial MMP-9 are linked to ventricular arrhythmia attacks after angiotensin II (Ang II) treatment. MMP-9-deficient mice were protected from ventricular arrhythmia...
December 14, 2016: Scientific Reports
keyword
keyword
53205
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"