Read by QxMD icon Read


Yingcong Yang, Zhongyuan Xia, Qingtao Meng, Kang Liu, Yeda Xiao, Liwei Shi
This study was designed to examine the effect and mechanism of dexmedetomidine (Dex) on neuropathic pain (NP). The NP model was established by performing chronic sciatic nerve constriction injury (CCI). Seven days after CCI surgery, the rats were injected intraperitoneally with Dex, ZD7288 (an HCN channel inhibitor), and saline, respectively. The paw withdrawal threshold to mechanical stimulation and the thermal withdrawal latency tests were performed. After administration, the L4, L5 dorsal root ganglia (DRG) neurons of rats were isolated...
June 14, 2018: Neuroreport
Nicole Silbernagel, Magdalena Walecki, Martin K-H Schäfer, Mirjam Kessler, Mehrnoush Zobeiri, Susanne Rinné, Aytug K Kiper, Marlene A Komadowski, Kirsty S Vowinkel, Konstantin Wemhöner, Lisa Fortmüller, Marcus Schewe, Amalia M Dolga, Jelena Scekic-Zahirovic, Lina A Matschke, Carsten Culmsee, Thomas Baukrowitz, Laurent Monassier, Nina D Ullrich, Luc Dupuis, Steffen Just, Thomas Budde, Larissa Fabritz, Niels Decher
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels encode neuronal and cardiac pacemaker currents. The composition of pacemaker channel complexes in different tissues is poorly understood, and the presence of additional HCN modulating subunits was speculated. Here we show that vesicle-associated membrane protein-associated protein B (VAPB), previously associated with a familial form of amyotrophic lateral sclerosis 8, is an essential HCN1 and HCN2 modulator. VAPB significantly increases HCN2 currents and surface expression and has a major influence on the dendritic neuronal distribution of HCN2...
June 7, 2018: FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology
Soledad Bárez-López, Meredith D Hartley, Carmen Grijota-Martínez, Thomas Scanlan, Ana Guadaño-Ferraz
Background Loss of function mutations in the thyroid hormone (TH)-specific cell membrane transporter, the monocarboxylate transporter 8 (MCT8), lead to profound psychomotor retardation and abnormal TH serum levels, with low thyroxine (T4) and high triiodothyronine (T3). Several studies point to impaired TH transport across brain barriers as a crucial pathophysiological mechanism resulting in cerebral hypothyroidism. Treatment options for MCT8-deficient patients are limited and are focused on overcoming the brain barriers...
May 30, 2018: Thyroid: Official Journal of the American Thyroid Association
Yao Xu, Shujun Chen, Ying Cao, Pingzheng Zhou, Zhipeng Chen, Kui Cheng
Toll-like receptor 4 (TLR4) initiates innate immune response to release inflammatory cytokines and has been pathologically linked to variety of inflammatory diseases. Recently, we found that Carvedilol, as the classic anti-heart failure and anti-inflammatory clinic drug, could inhibit the TLR4 signaling in the TLR4 overexpressed cells. Herein, we have designed and synthesized a small library of novel Carvedilol derivatives and investigated their potential inhibitory activity. The results indicate that the most potent compound 8a (SMU-XY3) could effectively inhibited TLR4 protein and the LPS triggered alkaline phosphatase signaling in HEK-Blue hTLR4 cells...
May 22, 2018: European Journal of Medicinal Chemistry
Xiaoyu Liu, Lidong Zhang, Li Jin, Yuanhui Tan, Weiyan Li, Jun Tang
Emerging evidence showed that hyperpolarization-activated cation channels (HCN) participate in the development of inflammatory and neuropathic pain. However, the role of HCN2 in oxaliplatin-induced neuropathic pain remains unknown. Here, we found that HCN2 expression was upregulated in a rat model of oxaliplatin-induced neuropathic pain. Intrathecal injection of ZD7288, an HCN specific inhibitor, decreased the HCN2 level, as well as weakened the neuropathic pain behaviors compared to naive rats. Besides, mechanistic studies revealed that the expression of the spinal N-methyl-D-aspartate receptor subunit 2B was increased after oxaliplatin administration and was reduced by ZD7288 administration...
January 2018: Molecular Pain
Sabine Hummert, Susanne Thon, Thomas Eick, Ralf Schmauder, Eckhard Schulz, Klaus Benndorf
Hyperpolarization-activated cyclic nucleotide-modulated (HCN) channels control electrical rhythmicity in specialized brain and heart cells. We quantitatively analysed voltage-dependent activation of homotetrameric HCN2 channels and its modulation by the second messenger cAMP using global fits of hidden Markovian models to complex experimental data. We show that voltage-dependent activation is essentially governed by two separable voltage-dependent steps followed by voltage-independent opening of the pore. According to this model analysis, the binding of cAMP to the channels exerts multiple effects on the voltage-dependent gating: It stabilizes the open pore, reduces the total gating charge from ~8 to ~5, makes an additional closed state outside the activation pathway accessible and strongly accelerates the ON-gating but not the OFF-gating...
March 2018: PLoS Computational Biology
Vaibhav P Pai, Alexis Pietak, Valerie Willocq, Bin Ye, Nian-Qing Shi, Michael Levin
Endogenous bioelectrical signaling coordinates cell behaviors toward correct anatomical outcomes. Lack of a model explaining spatialized dynamics of bioelectric states has hindered the understanding of the etiology of some birth defects and the development of predictive interventions. Nicotine, a known neuroteratogen, induces serious defects in brain patterning and learning. Our bio-realistic computational model explains nicotine's effects via the disruption of endogenous bioelectrical gradients and predicts that exogenous HCN2 ion channels would restore the endogenous bioelectric prepatterns necessary for brain patterning...
March 8, 2018: Nature Communications
Daniel W Fisher, Phillip Luu, Neha Agarwal, Jonathan E Kurz, Dane M Chetkovich
Hyperpolarization-activated Cyclic Nucleotide-gated (HCN) channels are important regulators of excitability in neural, cardiac, and other pacemaking cells, which are often altered in disease. In mice, loss of HCN2 leads to cardiac dysrhythmias, persistent spike-wave discharges similar to those seen in absence epilepsy, ataxia, tremor, reduced neuropathic and inflammatory pain, antidepressant-like behavior, infertility, and severely restricted growth. While many of these phenotypes have tissue-specific mechanisms, the cause of restricted growth in HCN2 knockout animals remains unknown...
2018: PloS One
Kuihao Chen, Dongchuan Zuo, Sho-Ya Wang, Haijun Chen
Spontaneous rhythmic action potential or pacemaking activity of pacemaker cells controls rhythmic signaling such as heartbeat. The mechanism underlying the origin of pacemaking activity is not well understood. In this study, we created human embryonic kidney (HEK) 293 cells that show pacemaking activity through heterologous expression of strong inward rectifier K+ channels (Kir2.1), hyperpolarization-activated cyclic nucleotide-gated nonselective cation channels (HCN2), and voltage-gated Na+ or Ca2+ channels (Nav 1...
January 12, 2018: FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology
Hsing-Jung Lai, Chien-Lin Chen, Li-Kai Tsai
OBJECTIVE: The pathophysiology of spinal muscular atrophy (SMA) is still unclear. METHODS: The nerve excitability test in SMA patients and a mouse model of SMA was carried out to explore the pathophysiology of nodal and internodal currents, and quantitative PCR, western blotting, and whole-cell patch-clamp recording were used for the identified hypothesis. RESULTS: The nerve excitability test in SMA patients showed increased inward rectification in the current-threshold relationship and increased overshoot after hyperpolarizing threshold electrotonus, which indicates increased hyperpolarization-activated cyclic nucleotide-gated (HCN) current; these findings correlated with disease severity...
March 2018: Annals of Neurology
Weihua Ding, Zerong You, Shiqian Shen, Jinsheng Yang, Grewo Lim, Jason T Doheny, Shengmei Zhu, Yi Zhang, Lucy Chen, Jianren Mao
Orofacial neuropathic pain caused by trigeminal nerve injury is a debilitating condition with limited therapeutic options. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels regulate neuronal excitability and are involved in the development and maintenance of chronic pain. However, the effect of HCN channel activity in the Gasserian ganglion on trigeminal neuropathic pain has not been examined. We evaluated nociceptive behaviors after microinjection of the HCN channel blockers ZD7288 or ivabradine into the Gasserian ganglion in rats with trigeminal nerve injury...
January 31, 2018: Journal of Pain: Official Journal of the American Pain Society
F Resta, L Micheli, A Laurino, V Spinelli, T Mello, L Sartiani, L Di Cesare Mannelli, E Cerbai, C Ghelardini, M N Romanelli, G Mannaioni, A Masi
Chemotherapy-Induced Peripheral Neuropathy (CIPN) is the most frequent adverse effect of pharmacological cancer treatments. The occurrence of neuropathy prevents the administration of fully-effective drug regimen, affects negatively the quality of life of patients, and may lead to therapy discontinuation. CIPN is currently treated with anticonvulsants, antidepressants, opioids and non-opioid analgesics, all of which are flawed by insufficient anti-hyperalgesic efficacy or addictive potential. Understandably, developing new drugs targeting CIPN-specific pathogenic mechanisms would dramatically improve efficacy and tolerability of anti-neuropathic therapies...
March 15, 2018: Neuropharmacology
Mengye Zhu, Vinay Kumar Idikuda, Jianbing Wang, Fusheng Wei, Virang Kumar, Nikhil Shah, Christopher B Waite, Qinglian Liu, Lei Zhou
KEY POINTS: Shank3 increases the HCN channel surface expression in heterologous expression systems. Shank3Δ13-16 deficiency causes significant reduction in HCN2 expression and Ih current amplitude in thalamocortical (TC) neurons. Shank3Δ13-16 - but not Shank3Δ4-9 -deficient TC neurons share changes in basic electrical properties which are comparable to those of HCN2-/- TC neurons. HCN channelopathy may critically mediate events downstream from Shank3 deficiency. ABSTRACT: SHANK3 is a scaffolding protein that is highly enriched in excitatory synapses...
April 1, 2018: Journal of Physiology
Kuihao Chen, Dongchuan Zuo, Zheng Liu, Haijun Chen
Strong inward rectifier K+ channels (Kir2.1) mediate background K+ currents primarily responsible for maintenance of resting membrane potential. Multiple types of cells exhibit two levels of resting membrane potential. Kir2.1 and K2P1 currents counterbalance, partially accounting for the phenomenon of human cardiomyocytes in subphysiological extracellular K+ concentrations or pathological hypokalemic conditions. The mechanism of how Kir2.1 channels contribute to the two levels of resting membrane potential in different types of cells is not well understood...
April 2018: Pflügers Archiv: European Journal of Physiology
Melody Li, Snezana Maljevic, A Marie Phillips, Slave Petrovski, Michael S Hildebrand, Rosemary Burgess, Therese Mount, Federico Zara, Pasquale Striano, Julian Schubert, Holger Thiele, Peter Nürnberg, Michael Wong, Judith L Weisenberg, Liu Lin Thio, Holger Lerche, Ingrid E Scheffer, Samuel F Berkovic, Steven Petrou, Christopher A Reid
Genetic generalized epilepsy (GGE) is a common epilepsy syndrome that encompasses seizure disorders characterized by spike-and-wave discharges (SWDs). Pacemaker hyperpolarization-activated cyclic nucleotide-gated channels (HCN) are considered integral to SWD genesis, making them an ideal gene candidate for GGE. We identified HCN2 missense variants from a large cohort of 585 GGE patients, recruited by the Epilepsy Phenome-Genome Project (EPGP), and performed functional analysis using two-electrode voltage clamp recordings from Xenopus oocytes...
February 2018: Human Mutation
Noriyuki Nakashima, Kie Nakashima, Takeo Nakayama, Akiko Takaku, Ryosuke Kanamori
The hyperpolarization-activated cyclic nucleotide-gated 2 (HCN2) channel is a major subtype of the HCN channel family expressed in the nervous system that sets the membrane potential, regulates cell excitability and senses changes in the extracellular environment. Neurons express various Gαs -protein-coupled receptors (GPCRs), many of which show ligand-independent constitutive activity. These membrane-bound proteins are expressed in various subcellular compartments of neurons. Therefore, some proportion of HCN2 channels opens in response to the basal cAMP pool size produced by constitutively active GPCRs...
December 9, 2017: Biochemical and Biophysical Research Communications
Shu-Zhi Wu, Hua Ye, Xiao-Guo Yang, Zhi-Li Lu, Qiang Qu, Jian Qu
Epilepsy is a common complex neurological disorder, and some forms are resistant to drug treatment. The HCN1/HCN2 genes encode hyperpolarization-activated cyclic nucleotide-gated channels, which play important roles in the electrophysiology of neurons. We investigated the association between HCN1/HCN2 variants and drug resistance or the risk of genetic generalized epilepsies (GGEs). We used matrix-assisted laser desorption/ionization time-of-flight mass spectrometry to assess nine variants of HCN1/HCN2 in 284 healthy participants and 483 GGEs (279 drug-responsive, 204 drug-resistant)...
March 2018: Clinical and Experimental Pharmacology & Physiology
Chandong Ding, Cuicui Yang, Quanxia Cao, Xiaoxia Zhu, Jianming Zhang, Wen Zhang, Yongping Wang, Long Li
Currently, the mechanism of the chronotropic ability of stem cells modified to express the hyperpolarization-activated cyclic nucleotide-gated (HCN) gene remains to be elucidated. The present study assessed the effects of mouse (m)HCN2 gene modification on the expression of chronotropic relevant receptors, adrenergic receptor β1 (Adrb1) and cholinergic receptor muscarinic M2 (Chrm2), in bone marrow stromal cells (BMSCs) co-cultured with atrial myocytes. BMSCs were divided into the following four groups: i) BMSCs transfected with the mHCN2 gene and co-cultured with atrial myocytes for 48 h (TF + CO); ii) respective transfection (TF); iii) respective co-culture (CO); and iv) the control group without treatment (CTL)...
September 2017: Experimental and Therapeutic Medicine
Christoforos Tsantoulas, Sergio Laínez, Sara Wong, Ishita Mehta, Bruno Vilar, Peter A McNaughton
Diabetic patients frequently suffer from continuous pain that is poorly treated by currently available analgesics. We used mouse models of type 1 and type 2 diabetes to investigate a possible role for the hyperpolarization-activated cyclic nucleotide-gated 2 (HCN2) ion channels as drivers of diabetic pain. Blocking or genetically deleting HCN2 channels in small nociceptive neurons suppressed diabetes-associated mechanical allodynia and prevented neuronal activation of second-order neurons in the spinal cord in mice...
September 27, 2017: Science Translational Medicine
Sebastien Hayoz, Purushottam B Tiwari, Grzegorz Piszczek, Aykut Üren, Tinatin I Brelidze
Hyperpolarization-activated cyclic nucleotide-modulated (HCN) channels control cardiac and neuronal rhythmicity. HCN channels contain cyclic nucleotide-binding domain (CNBD) in their C-terminal region linked to the pore-forming transmembrane segment with a C-linker. The C-linker couples the conformational changes caused by the direct binding of cyclic nucleotides to the HCN pore opening. Recently, cyclic dinucleotides were shown to antagonize the effect of cyclic nucleotides in HCN4 but not in HCN2 channels...
2017: PloS One
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"