Ion Channels

Two-dimensional transition metal dichalcogenide-based memtransistors provide simulation, sensing, and storage capabilities for applications in a remotely operated aerospace environment. Swift heavy ion (SHI) irradiation technology is a common method to simulate the influences of radiation ions on electronic devices in space environments. Here, SHI irradiation technology under different conditions was utilized to produce complex defects in WSe2 -based memtransistors. Low-resistance state to low-resistance state (LRS-LRS) switching behaviors under light illumination were achieved and photocurrent responses with different spike trains were observed in SHI-irradiated memtransistors, which facilitated the design of devices with enriched analog functions...

Anodic aluminum oxide (AAO) membranes were used as templates to control orientation of an ion-channel forming columnar mesophase obtained by self assembly of a wedge-shaped sulfonate molecule. Inside the AAO structure, the director vector of the mesophase is oriented parallel to the pore axis due to the confinement effect. The molecular arrangement induced by the spatial confinement within the pores is extended over several microns into the remnant film on the AAO surface. The homeotropic alignment of the channels promotes unidimensional ion conduction through the film plane, which is manifested by a considerable increase in conductivity relative to isotropic samples...

Scanning electrochemical microscopy (SECM) has emerged as a powerful method to quantitatively investigate the transport of molecules and ions across various biological membranes as represented by living cells. Advantageously, SECM allows for the in situ and non-destructive imaging and measurement of high membrane permeability under simple steady-state conditions, thereby facilitating quantitative data analysis. The SECM method, however, has not provided any information about the interactions of a transported species, i...

Patients with Fabry disease suffer from chronic debilitating pain and peripheral sensory neuropathy with minimal treatment options, but the cellular drivers of this pain are unknown. Here, we propose a mechanism we believe to be novel in which altered signaling between Schwann cells and sensory neurons underlies the peripheral sensory nerve dysfunction we observed in a genetic rat model of Fabry disease. Using in vivo and in vitro electrophysiological recordings, we demonstrated that Fabry rat sensory neurons exhibited pronounced hyperexcitability...

Organic electrochemical transistors (OECTs) have emerged as promising candidates for various fields, including bioelectronics, neuromorphic computing, biosensors, and wearable electronics. OECTs operate in aqueous solutions, exhibit high amplification properties, and offer ion-to-electron signal transduction. The OECT channel consists of a conducting polymer, with PEDOT:PSS receiving the most attention to date. While PEDOT:PSS is highly conductive, and benefits from optimized protocols using secondary dopants and detergents, new p-type and n-type polymers are emerging with desirable material properties...

Poly(ethylene oxide) (PEO)-based composite solid electrolytes (CSEs) are promising to accelerate commercialization of solid-state lithium metal batteries (SSLMBs). Nonetheless, this is hindered by the CSEs' limited ion conductivity at room temperature. Here, we propose design, synthesis, and application of the bioinspired neuron-like nanofillers for PEO-based CSEs. The neuron-like superhydrophobic nanofillers are synthesized by controllably grafting silicone nanofilaments onto montmorillonite nanosheets. Compared to various reported fillers, the nanofillers can greatly improve ionic conductivity (4...

BACKGROUND/AIMS: Extracellular acidic conditions impair cellular activities; however, some cancer cells drive cellular signaling to adapt to the acidic environment. It remains unclear how ovarian cancer cells sense changes in extracellular pH. This study was aimed at characterizing acid-inducible currents in an ovarian cancer cell line and evaluating the involvement of these currents in cell viability. METHODS: The biophysical and pharmacological properties of membrane currents in OV2944, a mouse ovarian cancer cell line, were studied using the whole-cell configuration of the patch-clamp technique...

SK3 channels are potassium channels found to promote tumour aggressiveness. We have previously demonstrated that SK3 is regulated by synthetic ether-lipids, but the role of endogenous ether lipids is unknown. Here, we have studied the role of endogenous alkyl- and alkenyl-ether-lipids on SK3 channels and on the biology of cancer cells. Experiments revealed that the suppression of AGPS or PEDS1, which are key enzymes for alkyl- and alkenyl-ether-lipid synthesis, respectively, decreased SK3 expression by increasing miR-499 and miR-208 expression, leading to a decrease in SK3-dependent calcium entry, cell migration, and MMP9-dependent cell adhesion and invasion...

Cellular zinc ions (Zn2+ ) are crucial for signal transduction in various cell types. The transient receptor potential (TRP) ankyrin 1 (TRPA1) channel, known for its sensitivity to intracellular Zn2+ ([Zn2+ ]i ), has been a subject of limited understanding regarding its molecular mechanism. Here, we employed metal ion-affinity prediction, three-dimensional structural modeling, and mutagenesis, utilizing data from the Protein Data Bank and AlphaFold Database, to elucidate the [Zn2+ ]i binding domain (IZD) structure composed by specific amino acid residues (AAs) in human (hTRPA1) and chicken TRPA1 (gTRPA1)...

Calcium ion (Ca2+ ) dysregulation is one of the main causes of neuronal cell death and brain damage after cerebral ischemia. During ischemic stroke, the ability of neurons to maintain Ca2+ homeostasis is compromised. Ca2+ regulates various functions of the nervous system, including neuronal activity and adenosine triphosphate (ATP) production. Disruptions in Ca2+ homeostasis can trigger a cascade of events, including activation of the unfolded protein response (UPR) pathway, which is associated with endoplasmic reticulum (ER) stress and mitochondrial dysfunction...

The ability of fungi to establish mycorrhizal associations with plants and enhance the acquisition of mineral nutrients stands out as a key feature of terrestrial life. Evidence indicates that arbuscular mycorrhizal (AM) association is a trait present in the common ancestor of land plants,1 , 2 , 3 , 4 suggesting that AM symbiosis was an important adaptation for plants in terrestrial environments.5 The activation of nuclear calcium signaling in roots is essential for AM within flowering plants.6 Given that the earliest land plants lacked roots, whether nuclear calcium signals are required for AM in non-flowering plants is unknown...

When activated by increase in intracellular Ca2+ , anoctamins (TMEM16 proteins) operate as phospholipid scramblases and as ion channels. Anoctamin 1 (ANO1) is the Ca2+ -activated epithelial anion-selective channel that is coexpressed together with the abundant scramblase ANO6 and additional intracellular anoctamins. In salivary and pancreatic glands, ANO1 is tightly packed in the apical membrane and secretes Cl- . Epithelia of airways and gut use cystic fibrosis transmembrane conductance regulator (CFTR) as an apical Cl- exit pathway while ANO1 supports Cl- secretion mainly by facilitating activation of luminal CFTR and basolateral K+ channels...

Macrophages (MΦ) play pivotal roles in tissue homeostasis and repair. Their mechanical environment has been identified as a key modulator of various cell functions, and MΦ mechanosensitivity is likely to be critical - in particular in a rhythmically contracting organ such as the heart. Cultured MΦ, differentiated in vitro from bone marrow (MΦBM ), form a popular research model. This study explores the activity of mechanosensitive ion channels (MSC) in murine MΦBM and compares it to MSC activity in MΦ enzymatically isolated from cardiac tissue (tissue-resident MΦ; MΦTR )...

Electroceuticals have evolved beyond devices manipulating neuronal signaling for symptomatic treatment, becoming more precise and disease modulating and expanding beyond the nervous system. These advancements promise transformative applications in arthritis, cancer treatment, tissue regeneration, and more. Here, we discuss these recent advances and offer insights for future research.

The mechanisms by which brain insults lead to subsequent epilepsy remain unclear. Insults including trauma, stroke, infections and long seizures (status epilepticus; SE) increase the nuclear expression and chromatin binding of the neuronal restrictive silencing factor / RE-1 silencing transcription factor (NRSF/REST). REST/NRSF orchestrates major disruption of the expression of key neuronal genes, including ion channels and neurotransmitter receptors, potentially contributing to epileptogenesis. Accordingly, transient interference with REST/NRSF chromatin binding after an epilepsy-provoking SE suppressed spontaneous seizures for the 12- day duration of a prior study...

Cholesterol is a negative regulator of a variety of ion channels. We have previously shown that cholesterol suppresses Kir2.2 channels via residue-residue uncoupling on the inter-subunit interfaces within the close state of the channels (3JYC). In this study, we extend this analysis to the other known structure of Kir2.2 that is closer to the open state of Kir2.2 channels (3SPI) and provide additional analysis of the residue distances between the uncoupled residues and cholesterol binding domains in the two conformation states of the channels...

The poor structural stability and conductivity of Na3 V2 (PO4 )3 (NVP) have been serious limitations to its development. In this paper, Sc3+ is selected to replace partial site of V3+ which can enhance its ability to bond with oxygen, forming the ScO6 octahedral unit, resulting in improved structural stability and better kinetic properties for the NVP system. Moreover, due to the larger ionic radius of Sc3+ compared to V3+ , moderate Sc3+ substitution can support the crystal framework as pillar ions and expand the migration channels for de-intercalation of Na+ , thus efficiently promoting ionic conductivity...

Digital precision medicine is gaining increasing importance in rhythmology, especially in the treatment of cardiac arrhythmias. This trend is driven by the advancing digitization in healthcare and the availability of large amounts of data from various sources such as electrocardiograms (ECGs), implants like pacemakers and implantable cardioverter-defibrillators (ICDs), as well as wearables like smartwatches and fitness trackers. Through the analysis of this data, physicians can develop more precise and individualized diagnoses and treatment strategies for patients with cardiac arrhythmias...

Only limited enhancement in room-temperature ionic-conductivity for poly(ethylene oxide), PEO, based electrolytes is possible due to coupling between ionic-conductivity and segmental relaxation. In the present study, we have achieved ionic-conductivity of 1.07 × 10-3 and 6.20 × 10-4 S cm-1 at 313 and 298 K, respectively, by adding 45 wt% of succinonitrile (SN) in PEO having low LiTFSI loading (Li : EO = 1 : 20). This enhancement in the ionic-conductivity is attributed to faster ion transport (diffusion coefficient, D = 3...

BACKGROUND: The goal was to determine the feasibility of mapping the injured-but-not-infarcted myocardium using 99m Tc-duramycin in the postischemic heart, with spatial information for its characterization as a pathophysiologically intermediate tissue, which is neither normal nor infarcted. METHODS AND RESULTS: Coronary occlusion was conducted in Sprague Dawley rats with preconditioning and 30-minute ligation. In vivo single-photon emission computed tomography was acquired after 3 hours (n=6) using 99m Tc-duramycin, a phosphatidylethanolamine-specific radiopharmaceutical...