keyword
MENU ▼
Read by QxMD icon Read
search

Vrac

keyword
https://www.readbyqxmd.com/read/28873008/induction-of-adipose-and-hepatic-swell1-expression-is-required-for-maintaining-systemic-insulin-sensitivity-in-obesity
#1
Litao Xie, Yanhui Zhang, Susheel Gunasekar, Anil Mishra, Lei Cao, Rajan Sah
Obesity is associated with a loss of insulin-sensitivity and systemic dysglycemia, resulting in Type 2 diabetes, however the molecular mechanisms underlying this association are unclear. Through adipocyte patch-clamp studies, we recently showed that SWELL1 is required for the Volume-Regulated Anion Current (VRAC) in adipocytes and that SWELL1-mediated VRAC is activated by both mechanical and pathophysiological adipocyte expansion. We also demonstrated that adipocyte SWELL1 is required for maintaining insulin signaling and glucose homeostasis, particularly in the setting of obesity...
September 5, 2017: Channels
https://www.readbyqxmd.com/read/28841766/subunit-dependent-oxidative-stress-sensitivity-of-lrrc8-volume-regulated-anion-channels
#2
Antonella Gradogna, Paola Gavazzo, Anna Boccaccio, Michael Pusch
The volume-regulated anion channel (VRAC) is formed by heteromers of LRRC8 proteins containing the essential LRRC8A subunit and at least one among the LRRC8B-E subunits. Reactive oxygen species (ROS) play physiological and pathophysiological roles and VRAC channels are highly ROS sensitive. However, it is unclear if ROS act directly on the channels or on molecules involved in the activation pathway. We used fluorescently tagged LRRC8 proteins that yield large constitutive currents to test direct effects of oxidation...
August 25, 2017: Journal of Physiology
https://www.readbyqxmd.com/read/28833202/molecular-composition-and-heterogeneity-of-the-lrrc8-containing-swelling-activated-osmolyte-channels-in-primary-rat-astrocytes
#3
Alexandra L Schober, Corinne S Wilson, Alexander A Mongin
Volume-regulated anion channel (VRAC) is the ubiquitously expressed vertebrate Cl(-) /anion channel that is comprised of proteins belonging to the LRRC8 family and activated by cell swelling. In the brain, VRAC contributes to physiological and pathological release of a variety of small organic molecules, including the amino acid neurotransmitters glutamate, aspartate, and taurine. In the present work, we explored the role of all five LRRC8 family members in the release of organic osmolytes from primary rat astrocytes...
August 22, 2017: Journal of Physiology
https://www.readbyqxmd.com/read/28826988/transapical-transcatheter-aortic-valve-implantation-using-a-new-tavi-system-for-high-risk-patients-with-severe-aortic-stenosis
#4
Xu Fei, Yacine Elhmidi, Bengui Zhang, Hong Tang, Da Zhu, Yucheng Chen, Yingqiang Guo
BACKGROUND: To evaluate the safety and efficacy of transcatheter aortic valve implantation (TAVI) for high-risk patients with aortic stenosis using the J-Valve system. METHODS: 30 high-risk patients with severe AS underwent TAVI procedure were enrolled with mean age 74.5±4.5 years and mean logistic Euro-SCORE-I of 28.4±9.6%. All patients were followed up for six months. Outcomes were analyzed in accordance with the updated standardised endpoints defined by the Valve Academic Research Consortium -2 (VRAC-2) criteria...
August 8, 2017: Heart, Lung & Circulation
https://www.readbyqxmd.com/read/28620305/comparative-effects-of-chloride-channel-inhibitors-on-lrrc8-vrac-mediated-chloride-conductance
#5
Jonas Friard, Michel Tauc, Marc Cougnon, Vincent Compan, Christophe Duranton, Isabelle Rubera
Chloride channels play an essential role in a variety of physiological functions and in human diseases. Historically, the field of chloride channels has long been neglected owing to the lack of powerful selective pharmacological agents that are needed to overcome the technical challenge of characterizing the molecular identities of these channels. Recently, members of the LRRC8 family have been shown to be essential for generating the volume-regulated anion channel (VRAC) current, a chloride conductance that governs the regulatory volume decrease (RVD) process...
2017: Frontiers in Pharmacology
https://www.readbyqxmd.com/read/28584113/consequences-of-rapid-ice-sheet-melting-on-the-sahelian-population-vulnerability
#6
Dimitri Defrance, Gilles Ramstein, Sylvie Charbit, Mathieu Vrac, Adjoua Moïse Famien, Benjamin Sultan, Didier Swingedouw, Christophe Dumas, François Gemenne, Jorge Alvarez-Solas, Jean-Paul Vanderlinden
The acceleration of ice sheet melting has been observed over the last few decades. Recent observations and modeling studies have suggested that the ice sheet contribution to future sea level rise could have been underestimated in the latest Intergovernmental Panel on Climate Change report. The ensuing freshwater discharge coming from ice sheets could have significant impacts on global climate, and especially on the vulnerable tropical areas. During the last glacial/deglacial period, megadrought episodes were observed in the Sahel region at the time of massive iceberg surges, leading to large freshwater discharges...
June 20, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28436964/swell1-is-a-regulator-of-adipocyte-size-insulin-signalling-and-glucose-homeostasis
#7
Yanhui Zhang, Litao Xie, Susheel K Gunasekar, Dan Tong, Anil Mishra, William J Gibson, Chuansong Wang, Trevor Fidler, Brodie Marthaler, Aloysius Klingelhutz, E Dale Abel, Isaac Samuel, Jessica K Smith, Lei Cao, Rajan Sah
Adipocytes undergo considerable volumetric expansion in the setting of obesity. It has been proposed that such marked increases in adipocyte size may be sensed via adipocyte-autonomous mechanisms to mediate size-dependent intracellular signalling. Here, we show that SWELL1 (LRRC8a), a member of the Leucine-Rich Repeat Containing protein family, is an essential component of a volume-sensitive ion channel (VRAC) in adipocytes. We find that SWELL1-mediated VRAC is augmented in hypertrophic murine and human adipocytes in the setting of obesity...
May 2017: Nature Cell Biology
https://www.readbyqxmd.com/read/28298618/new-insights-into-vrac-composition-and-substrates
#8
(no author information available yet)
No abstract text is available yet for this article.
March 15, 2017: Journal of Cell Science
https://www.readbyqxmd.com/read/28289711/the-volume-regulated-anion-channel-lrrc8-in-nodose-neurons-is-sensitive-to-acidic-ph
#9
Runping Wang, Yongjun Lu, Susheel Gunasekar, Yanhui Zhang, Christopher J Benson, Mark W Chapleau, Rajan Sah, François M Abboud
The leucine rich repeat containing protein 8A (LRRC8A), or SWELL1, is an essential component of the volume-regulated anion channel (VRAC) that is activated by cell swelling and ionic strength. We report here for the first time to our knowledge its expression in a primary cell culture of nodose ganglia neurons and its localization in the soma, neurites, and neuronal membrane. We show that this neuronal VRAC/SWELL1 senses low external pH (pHo) in addition to hypoosmolarity. A robust sustained chloride current is seen in 77% of isolated nodose neurons following brief exposures to extracellular acid pH...
March 9, 2017: JCI Insight
https://www.readbyqxmd.com/read/28193731/selective-transport-of-neurotransmitters-and-modulators-by-distinct-volume-regulated-lrrc8-anion-channels
#10
Darius Lutter, Florian Ullrich, Jennifer C Lueck, Stefan Kempa, Thomas J Jentsch
In response to swelling, mammalian cells release chloride and organic osmolytes through volume-regulated anion channels (VRACs). VRACs are heteromers of LRRC8A and other LRRC8 isoforms (LRRC8B to LRRC8E), which are co-expressed in HEK293 and most other cells. The spectrum of VRAC substrates and its dependence on particular LRRC8 isoforms remains largely unknown. We show that, besides the osmolytes taurine and myo-inositol, LRRC8 channels transport the neurotransmitters glutamate, aspartate and γ-aminobutyric acid (GABA) and the co-activator D-serine...
March 15, 2017: Journal of Cell Science
https://www.readbyqxmd.com/read/28192143/lrrc8a-dependent-volume-regulated-anion-channel-activity-is-dispensable-for-t-cell-development-and-function
#11
Craig D Platt, Janet Chou, Patrick Houlihan, Yousef R Badran, Lalit Kumar, Wayne Bainter, P Luigi Poliani, Carlos J Perez, Sharon Y R Dent, David E Clapham, Fernando Benavides, Raif S Geha
BACKGROUND: Leucine-rich repeat containing 8A (LRRC8A) is a ubiquitously expressed transmembrane protein with 17 LRRs at its C-terminal end, and is an essential component of the volume regulated anion channel (VRAC) which controls cellular volume. A heterozygous mutation in LRRC8A that truncates the two terminal LRRs was reported in a patient with agammaglobulinemia and absent B cells, and was demonstrated to exert a dominant negative effect on T and B cell development in mice. Lrrc8a(-/-) mice have severely defective T cell development and function...
February 9, 2017: Journal of Allergy and Clinical Immunology
https://www.readbyqxmd.com/read/28130109/hypotonicity-activates-a-voltage-dependent-membrane-conductance-in-n2a-neuroblastoma-cells
#12
Akiyuki Taruno, Yoshinori Marunaka
To maintain cellular and bodily homeostasis, cells respond to extracellular stimuli including osmotic stress by activating various ion channels, which have been implicated in many physiological and pathophysiological conditions. However, cellular osmosensory mechanisms remain elusive. Here, we report a novel voltage-dependent current in N2a cells activated by exposure to hypotonic stress. After a hypotonic challenge, N2a cells sequentially develop two distinct currents. The volume-regulated anion channel (VRAC) current emerges first and, after a delay, activation of a previously uncharacterized strongly outwardly rectifying current follows...
March 4, 2017: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/28121479/cisplatin-activates-volume-sensitive-lrrc8-channel-mediated-currents-in-xenopus-oocytes
#13
Antonella Gradogna, Héctor Gaitán-Peñas, Anna Boccaccio, Raúl Estévez, Michael Pusch
LRRC8 proteins have been shown to underlie the ubiquitous volume regulated anion channel (VRAC). VRAC channels are composed of the LRRC8A subunit and at least one among the LRRC8B-E subunits. In addition to their role in volume regulation, LRRC8 proteins have been implicated in the uptake of chemotherapeutic agents. We had found that LRRC8 channels can be conveniently expressed in Xenopus oocytes, a system without endogenous VRAC activity. The fusion with fluorescent proteins yielded constitutive activity for A/C, A/D and A/E heteromers...
May 4, 2017: Channels
https://www.readbyqxmd.com/read/27875957/editorial
#14
COMMENT
Subhash C Basak, Marjan Vrac Ko, Frank A Witzmann
No abstract text is available yet for this article.
2016: Current Computer-aided Drug Design
https://www.readbyqxmd.com/read/27796579/calcium-is-not-required-for-triggering-volume-restoration-in-hypotonically-challenged-a549-epithelial-cells
#15
Olga Ponomarchuk, Francis Boudreault, Sergei N Orlov, Ryszard Grygorczyk
Maintenance of cell volume is a fundamental housekeeping function in eukaryotic cells. Acute cell swelling activates a regulatory volume decrease (RVD) process with poorly defined volume sensing and intermediate signaling mechanisms. Here, we analyzed the putative role of Ca(2+) signaling in RVD in single substrate-adherent human lung epithelial A549 cells. Acute cell swelling was induced by perfusion of the flow-through imaging chamber with 50 % hypotonic solution at a defined fluid turnover rate. Changes in cytosolic Ca(2+) concentration ([Ca(2+)]i) and cell volume were monitored simultaneously with ratiometric Fura-2 fluorescence and 3D reconstruction of stereoscopic single-cell images, respectively...
November 2016: Pflügers Archiv: European Journal of Physiology
https://www.readbyqxmd.com/read/27764579/specific-and-essential-but-not-sufficient-roles-of-lrrc8a-in-the-activity-of-volume-sensitive-outwardly-rectifying-anion-channel-vsor
#16
Toshiaki Okada, Md Rafiqul Islam, Nargiza A Tsiferova, Yasunobu Okada, Ravshan Z Sabirov
The broadly expressed volume-sensitive outwardly rectifying anion channel (VSOR, also called VRAC) plays essential roles in cell survival and death. Recent findings have suggested that LRRC8A is a core component of VSOR in human cells. In the present study, VSOR currents were found to be largely reduced by siRNA against LRRC8A in mouse C127 cells as well. In contrast, LRRC8A knockdown never affected activities of 4 other types of anion channel activated by acid, Ca(2+), patch excision or cAMP. While cisplatin-resistant KCP-4 cells poorly expressed endogenous VSOR activity, molecular expression levels of LRRC8A, LRRC8D and LRRC8E were indistinguishable between VSOR-deficient KCP-4 cells and the parental VSOR-rich KB cells...
March 4, 2017: Channels
https://www.readbyqxmd.com/read/27705766/investigation-of-lrrc8-mediated-volume-regulated-anion-currents-in-xenopus-oocytes
#17
Héctor Gaitán-Peñas, Antonella Gradogna, Lara Laparra-Cuervo, Carles Solsona, Victor Fernández-Dueñas, Alejandro Barrallo-Gimeno, Francisco Ciruela, Melike Lakadamyali, Michael Pusch, Raúl Estévez
Volume-regulated anion channels (VRACs) play an important role in controlling cell volume by opening upon cell swelling. Recent work has shown that heteromers of LRRC8A with other LRRC8 members (B, C, D, and E) form the VRAC. Here, we used Xenopus oocytes as a simple system to study LRRC8 proteins. We discovered that adding fluorescent proteins to the C-terminus resulted in constitutive anion channel activity. Using these constructs, we reproduced previous findings indicating that LRRC8 heteromers mediate anion and osmolyte flux with subunit-dependent kinetics and selectivity...
October 4, 2016: Biophysical Journal
https://www.readbyqxmd.com/read/27688432/leucine-rich-repeat-containing-protein-lrrc8a-is-essential-for-swelling-activated-cl-currents-and-embryonic-development-in-zebrafish
#18
Toshiki Yamada, Robert Wondergem, Rebecca Morrison, Viravuth P Yin, Kevin Strange
A volume-regulated anion channel (VRAC) has been electrophysiologically characterized in innumerable mammalian cell types. VRAC is activated by cell swelling and mediates the volume regulatory efflux of Cl(-) and small organic solutes from cells. Two groups recently identified the mammalian leucine-rich repeat containing protein LRRC8A as an essential VRAC component. LRRC8A must be coexpressed with at least one of the other four members of this gene family, LRRC8B-E, to reconstitute VRAC activity in LRRC8(-/-) cells...
October 2016: Physiological Reports
https://www.readbyqxmd.com/read/27514381/relationship-between-tmem16a-anoctamin-1-and-lrrc8a
#19
Roberta Benedetto, Lalida Sirianant, Ines Pankonien, Podchanart Wanitchakool, Jiraporn Ousingsawat, Ines Cabrita, Rainer Schreiber, Margarida Amaral, Karl Kunzelmann
TMEM16A/anoctamin 1/ANO1 and VRAC/LRRC8 are independent chloride channels activated either by increase in intracellular Ca(2+) or cell swelling, respectively. In previous studies, we observed overlapping properties for both types of channels. (i) TMEM16A/ANO1 and LRRC8 are inhibited by identical compounds, (ii) the volume-regulated anion channel VRAC requires compartmentalized Ca(2+) increase to be fully activated, (iii) anoctamins are activated by cell swelling, (iv) both channels have a role for apoptotic cell death, (v) both channels are possibly located in lipid rafts/caveolae like structures, and (vi) VRAC and anoctamin 1 currents are not additive when each are fully activated...
October 2016: Pflügers Archiv: European Journal of Physiology
https://www.readbyqxmd.com/read/27358231/channels-and-volume-changes-in-the-life-and-death-of-the-cell
#20
REVIEW
Herminia Pasantes-Morales
Volume changes deviating from original cell volume represent a major challenge for cellular homeostasis. Cell volume may be altered either by variations in the external osmolarity or by disturbances in the transmembrane ion gradients that generate an osmotic imbalance. Cells respond to anisotonicity-induced volume changes by active regulatory mechanisms that modify the intracellular/extracellular concentrations of K(+), Cl(-), Na(+), and organic osmolytes in the direction necessary to reestablish the osmotic equilibrium...
September 2016: Molecular Pharmacology
keyword
keyword
101546
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"