Read by QxMD icon Read


Anne-Cécile Boulay, Alice Gilbert, Vanessa Oliveira Moreira, Corinne Blugeon, Sandrine Perrin, Juliette Pouch, Stéphane Le Crom, Bertrand Ducos, Martine Cohen-Salmon
Astrocytes are the most abundant glial cells of the central nervous system and have recently been recognized as crucial in the regulation of brain immunity. In most neuropathological conditions, astrocytes are prone to a radical phenotypical change called reactivity, which plays a key role in astrocyte contribution to neuroinflammation. However, how astrocytes regulate brain immunity in healthy conditions is an understudied question. One of the astroglial molecule involved in these regulations might be Connexin 43 (Cx43), a gap junction protein highly enriched in astrocyte perivascular endfeet-terminated processes forming the glia limitans...
March 22, 2018: Brain Sciences
Arndt Meyer, Shubhash Chandra Yadav, Karin Dedek
In the mammalian retina, gap junctions, made of connexin proteins, are found in all neuronal cell types and are important for the transmission of rod photoreceptor signals, spike synchronization, noise reduction, and signal averaging. There are several methods available to assess gap junctional coupling in the retina: simultaneous electrical recordings from two adjacent cells, cut-loading, and intracellular injection of gap junction-permeable tracers. Here, we focus on the latter as it allows precise targeting of the cell of interest and is suitable to assess tracer coupling in a wide variety of retinal cell types, e...
2018: Methods in Molecular Biology
Luna Jammal, Ben Whalley, Edi Barkai
Training rats in a complex olfactory discrimination task results in acquisition of 'rule learning' (learning how to learn), a term describing the capability to perform the task superbly. Such rule learning results in strengthening of both excitatory and inhibitory synaptic connections between neurons in the piriform cortex. Moreover, intrinsic excitability is also enhanced throughout the pyramidal neuron population. Surprisingly, the cortical network retains its stability under these long-term modifications...
March 21, 2018: Journal of Neurophysiology
Robert Galinsky, Joanne O Davidson, Justin M Dean, Colin R Green, Laura Bennet, Alistair J Gunn
Perinatal encephalopathy remains a major cause of disability, such as cerebral palsy. Therapeutic hypothermia is now well established to partially reduce risk of disability in late preterm/term infants. However, new and complementary therapeutic targets are needed to further improve outcomes. There is increasing evidence that glia play a key role in neural damage after hypoxia-ischemia and infection/inflammation. In this review, we discuss the role of astrocytic gap junction (connexin) hemichannels in the spread of neural injury after hypoxia-ischemia and/or infection/inflammation...
February 2018: Neural Regeneration Research
Aleksandra Aljakna, Estelle Lauer, Sébastien Lenglet, Silke Grabherr, Tony Fracasso, Marc Augsburger, Sara Sabatasso, Aurélien Thomas
Simultaneous assessment of a panel of protein markers is becoming essential in order to enhance biomarker research and improve diagnostics. Specifically, postmortem diagnostics of early myocardial ischemia in sudden cardiac death cases could benefit from a multiplex marker assessment in the same tissue section. Current analytical antibody-based techniques (immunohistochemistry and immunofluorescence) limit multiplex analysis usually to not more than three antibodies. In this study, mass spectrometry-immunohistochemistry (MS-IHC) was performed by combining laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) with rare-metal-isotope-tagged antibodies as a technique for multiplex analysis of human postmortem myocardial tissue samples...
March 19, 2018: International Journal of Legal Medicine
Kirsten F Smit, Moritz Konkel, Raphaela Kerindongo, Maximilian A Landau, Coert J Zuurbier, Markus W Hollmann, Benedikt Preckel, Rienk Nieuwland, Martin Albrecht, Nina C Weber
Caveolins are involved in anaesthetic-induced cardioprotection. Actin filaments are located in close connection to Caveolins in the plasma membrane. We hypothesised that helium might affect the cytoskeleton and induce secretion of Caveolin. HCAEC, HUVEC and Cav-1 siRNA transfected HUVEC were exposed for 20 minutes to either helium (5% CO2 , 25% O2 , 70% He) or control gas (5% CO2 , 25% O2 , 70% N2 ). Cells and supernatants were collected for infrared Western blot analysis, immunofluorescence staining, nanoparticle tracking analysis and permeability measurements...
March 19, 2018: Scientific Reports
Akira Yoshida, Jong-Kook Lee, Satoki Tomoyama, Keiko Miwa, Keiichi Shirakawa, Sanae Hamanaka, Tomoyuki Yamaguchi, Hiromitsu Nakauchi, Shigeru Miyagawa, Yoshiki Sawa, Issei Komuro, Yasushi Sakata
Aims: The aim of the present study is to develop in vitro experimental analytical method for the electrophysiological properties of allogeneic induced pluripotent stem cell-derived cardiomyocytes (CMs) in cardiac conduction defect model. Methods and results: Cardiomyocytes were derived from rat induced pluripotent stem cells CMs (riPSC-CMs) using an embryoid body-based differentiation method with the serial application of growth factors including activin-A, bone morphogenetic protein 4 (BMP-4), and inhibitor of wnt production 2 (IWP-2)...
March 15, 2018: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
Álvaro Sebastián-Serrano, Laura de Diego-García, David C Henshall, Tobías Engel, Miguel Díaz-Hernández
Hypophosphatasia (HPP) is a rare heritable metabolic bone disease caused by hypomorphic mutations in the ALPL (in human) or Akp2 (in mouse) gene, encoding the tissue-nonspecific alkaline phosphatase (TNAP) enzyme. In addition to skeletal and dental malformations, severe forms of HPP are also characterized by the presence of spontaneous seizures. Initially, these seizures were attributed to an impairment of GABAergic neurotransmission caused by altered vitamin B6 metabolism. However, recent work by our group using knockout mice null for TNAP (TNAP-/-), a well-described model of infantile HPP, has revealed a deregulation of purinergic signaling contributing to the seizure phenotype...
2018: Frontiers in Pharmacology
Wen Hao, Shutian Shi, Shenghui Zhou, Xiao Wang, Shaoping Nie
This study aimed to examine the effects of aspirin on the growth and cardiomyocyte differentiation grade of bone marrow mesenchymal stem cells (BMMSCs). BMMSCs were divided into five differentiation groups with different concentrations of aspirin (0mM, 0.5mM, 1mM, 2mM, or 5mM), and a undifferentiated control group. Cell growth was measured by cell proliferation, apoptosis assays and DNA cycle analysis. The differentiation grade of BMMSC-derived cardiomyocyte-like cells was examined by measuring the levels of cardiac-specific proteins with cyto-immunofluorescence staining, flow cytometry, and Western blotting...
March 15, 2018: European Journal of Pharmacology
Chenju Yi, Jérémy Theillon, Annette Koulakoff, Hugues Berry, Christian Giaume
Intercellular communication through gap junction channels plays a key role in cellular homeostasis and in synchronizing physiological functions, a feature that is modified in number of pathological situations. In the brain, astrocytes are the cell population that expresses the highest amount of gap junction proteins, named connexins. Several techniques have been used to assess the level of gap junctional communication in astrocytes, but so far they remain very difficult to apply in adult brain tissue. Here, using specific loading of astrocytes with sulforhodamine 101, we adapted the gap-FRAP (Fluorescence Recovery After Photobleaching) to acute hippocampal slices from 9 month-old adult mice...
March 15, 2018: Journal of Neuroscience Methods
Robert D Johnson, Patrizia Camelliti
The heart is a complex organ composed of multiple cell types, including cardiomyocytes and different non-myocyte populations, all working closely together to determine the hearts properties and maintain normal cardiac function. Connexins are abundantly expressed proteins that form plasma membrane hemichannels and gap junctions between cells. Gap junctions are intracellular channels that allow for communication between cells, and in the heart they play a crucial role in cardiac conduction by coupling adjacent cardiomyocytes...
March 15, 2018: International Journal of Molecular Sciences
Shivani Mishra, Himani Pandey, Priyanka Srivastava, Kausik Mandal, Shubha R Phadke
OBJECTIVE: To determine the prevalence and spectrum of Connexin 26 (GJB2) mutations in pre-lingual non-syndromic hearing loss (NSHL) patients in authors' centre and to review the data of Indian patients from the literature. METHODS: Sanger sequencing of entire coding region contained in single exon (Exon 2) of GJB2 gene in 15 patients of NSHL. RESULTS: GJB2 mutations were found in 40% (6/15) of NSHL patients, out of which mono-allelic were 33...
March 15, 2018: Indian Journal of Pediatrics
F de Michele, J Poels, M G Giudice, F De Smedt, J Ambroise, M Vermeulen, D Gruson, C Wyns
STUDY QUESTION: How does the formation of the blood-testis barrier (BTB), as reflected by the expression of connexin 43 and claudin 11 proteins during the pubertal transition period, take place in vitro compared to samples from a large cohort of pre/peripubertal boys? SUMMARY ANSWER: The BTB connexin 43 and claudin 11 expression patterns appeared to be partially achieved in organotypic culture when compared to that in samples from 71 pre/peripubertal patients. WHAT IS KNOWN ALREADY: Although alterations in the protein expression patterns of the BTB, whose main components are connexin 43 and claudin 11, are known to be associated with impaired spermatogenesis in mice and adult men, there is a lack of knowledge on its formation in pre-peripubertal human tissue both in vitro and in vivo...
March 12, 2018: Molecular Human Reproduction
Jan Raska, Lucie Ctverackova, Aneta Dydowiczova, Iva Sovadinova, Ludek Blaha, Pavel Babica
HL1-hT1 cell line represents adult human liver stem cells (LSCs) immortalized with human telomerase reverse transcriptase. In this study, HL1-hT1 cells were found to express mesenchymal markers (vimentin, CD73, CD90/THY-1 and CD105) and an early hepatic endoderm marker FOXA2, while not expressing hepatic progenitor (HNF4A, LGR5, α-fetoprotein) or differentiated hepatocyte markers (albumin, transthyretin, connexin 32). In response to microcystin-LR (MC-LR), a time- and concentration-dependent formation of MC-positive protein bands in HL1-hT1 cells was observed...
March 10, 2018: Toxicology and Applied Pharmacology
Sara Crespo Yanguas, Tereza C da Silva, Isabel V A Pereira, Joost Willebrords, Michaël Maes, Marina Sayuri Nogueira, Inar Alves de Castro, Isabelle Leclercq, Guilherme R Romualdo, Luís F Barbisan, Luc Leybaert, Bruno Cogliati, Mathieu Vinken
Although a plethora of signaling pathways are known to drive the activation of hepatic stellate cells in liver fibrosis, the involvement of connexin-based communication in this process remains elusive. Connexin43 expression is enhanced in activated hepatic stellate cells and constitutes the molecular building stone of hemichannels and gap junctions. While gap junctions support intercellular communication, and hence the maintenance of liver homeostasis, hemichannels provide a circuit for extracellular communication and are typically opened by pathological stimuli, such as oxidative stress and inflammation...
March 12, 2018: International Journal of Molecular Sciences
Akiyuki Taruno
Adenosine triphosphate (ATP) has been well established as an important extracellular ligand of autocrine signaling, intercellular communication, and neurotransmission with numerous physiological and pathophysiological roles. In addition to the classical exocytosis, non-vesicular mechanisms of cellular ATP release have been demonstrated in many cell types. Although large and negatively charged ATP molecules cannot diffuse across the lipid bilayer of the plasma membrane, conductive ATP release from the cytosol into the extracellular space is possible through ATP-permeable channels...
March 11, 2018: International Journal of Molecular Sciences
Annalucia Carbone, Roberto Zefferino, Elisa Beccia, Valeria Casavola, Stefano Castellani, Sante Di Gioia, Valentina Giannone, Manuela Seia, Antonella Angiolillo, Carla Colombo, Maria Favia, Massimo Conese
We previously found that human amniotic mesenchymal stem cells (hAMSCs) in coculture with CF immortalised airway epithelial cells (CFBE41o- line, CFBE) on Transwell® filters acquired an epithelial phenotype and led to the expression of a mature and functional CFTR protein. In order to explore the role of gap junction- (GJ-) mediated intercellular communication (GJIC) in this rescue, cocultures (hAMSC : CFBE, 1 : 5 ratio) were studied for the formation of GJIC, before and after silencing connexin 43 (Cx43), a major component of GJs...
2018: Stem Cells International
Ipsita Mohanty, Subas Chandra Parija, Sujit Suklabaidya, Satish Rattan
Extracellular pH is an important physiological determinant of vascular tone that is normally maintained within 7.35-7.45. Any change outside this range leads to severe pathological repercussions. We investigated the unknown effects of extracellular acidosis on relaxation in the superior mesenteric artery (SMA) of goat. SMA rings were employed to maintain isometric contractions at extracellular pH (pHo ) 7.4 and 6.8. We analyzed the effect of acidosis (pHo 6.8) compared to physiological pH (pHo 7.4) on three signaling mediators of endothelium-dependent hyperpolarization: nitric oxide (NO), prostaglandin I2 (PGI2 ), and myoendothelial gap junctions (MEGJ)...
March 7, 2018: European Journal of Pharmacology
Sarah Falk
Pain is a major complication for cancer patients significantly compromising their quality of life. Current treatment is far from optimal and particularly bone-related cancer pain poses an increasing clinical and socio-economical problem. Connexins, key proteins in cell-cell communication, have the potential to affect cancer-induced bone pain at multiple levels, including nociceptive signaling and bone degradation. This study tested the analgesic potential of carbenoxolone, a broad-acting connexin blocker, in a mouse model of cancer-induced bone pain...
March 6, 2018: Pain
Amandine Jullienne, Andrew M Fukuda, Aleksandra Ichkova, Nina Nishiyama, Justine Aussudre, André Obenaus, Jérôme Badaut
Aquaporins (AQPs) facilitate water diffusion through the plasma membrane. Brain aquaporin-4 (AQP4) is present in astrocytes and has critical roles in normal and disease physiology. We previously showed that a 24.9% decrease in AQP4 expression after in vivo silencing resulted in a 45.8% decrease in tissue water mobility as interpreted from magnetic resonance imaging apparent diffusion coefficients (ADC). Similar to previous in vitro studies we show decreased expression of the gap junction protein connexin 43 (Cx43) in vivo after intracortical injection of siAQP4 in the rat...
March 8, 2018: Scientific Reports
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"