2-(Cyclohexyldimethylammoniumethyl)ether of 4-stilbenol (2), and its styryl-modified analogues 21 and 22, were identified as lead compounds from a series targeting human α9α10, α9, and α7 nicotinic acetylcholine receptors (nAChRs). Compounds 2 and 21 exhibited potent, and subtype-selective modulation of α9-containing receptors, with low nanomolar IC50 values and dual agonist/antagonist activity in a concentration-dependent manner. In contrast, compound 22 acted as a selective, pure antagonist. Molecular dynamics (MD) simulations of compound 21 supported a concentration-dependent allosteric mechanism, with orthosteric binding at low concentrations and vestibular site interaction at higher levels. In a human monocytic cell line, all three compounds inhibited ATP-induced IL-1β release at nanomolar concentrations. These findings identify α9α10-selective ligands as promising scaffolds for the development of nonopioid analgesics and immunomodulators, with favorable selectivity over α7 nAChRs to minimize CNS-related side effects.

Introduction Progressive supranuclear palsy (PSP) is a neurodegenerative disorder characterized by a wide spectrum of motor and cognitive impairments. Structural brain imaging biomarkers, such as the Magnetic Resonance Parkinsonism Index 2.0 (MRPI 2.0), are increasingly recognized as means of supporting a PSP diagnosis. These anatomic measures lack neurobiological correlates. In the present work, we investigated whether structural brain changes captured by MRPI 2.0 associate with whole-brain and regional cholinergic nerve terminal deficits in PSP. Methods Structural magnetic resonance (MR) and vesicular acetylcholine transporter (VAChT) [ 18 F]-fluoroethoxybenzovesamicol ([ 18 F]-FEOBV) PET imaging was obtained in a sample of 16 PSP subjects. MRPI 2.0 index was quantified and correlated with whole brain VAChT binding using statistical parametric mapping (SPM), after adjustment for sex, dopaminergic medication dose and disease duration. Post hoc multiple regression analyses were performed to correlate regional mean VAChT binding with MRPI 2.0 (after adjusting for the same covariates), characterizing the proportion of variance in cholinergic terminal deficits explained by this structural index. Results Voxel-wise SPM analyses revealed that MRPI 2.0 is significantly associated with cholinergic nerve terminal loss in brainstem, especially pontomesencephalic, limbic structures, insula, basal ganglia, thalamus, and cerebellar regions. Post hoc multiple regression analysis demonstrated that MRPI 2.0 accounts for about half of the variance in cholinergic nerve terminal integrity within relevant brain structures in PSP, showing the most robust association in the thalamus. Discussion Structural brain changes associated with higher MRPI 2.0 index scores may be a reliable proxy measure of cholinergic terminal deficits in PSP, predominantly those in subcortical regions. Differential association of subcortical brain region cholinergic deficits with PSP-specific structural brain changes may reflect the characteristic pattern of 4R-tau pathology observed in PSP.

Nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels mediating synaptic transmission at neuromuscular junctions and within both the central and peripheral nervous systems. The psychrophilic fungal tetrapeptide WvVf-OCH3 exhibits ∼55% inhibition of human muscle-type nAChR (hα1β1εδ) at 10 μM, suggesting potential for optimization. Structure-activity studies identified analogues, WrFr-OCH3 and WrFk-OCH3, with significantly increased potency (75-90% inhibition at 1 μM) against hα1β1εδ nAChRs and, notably, the hα9α10 subtype. These analogues exhibit high-affinity binding through stable π-π stacking with the principal face and electrostatic interactions with the complementary face of the receptor binding site. Their unique alternating L/D chirality enhances proteolytic stability. In vivo, intravenous application of WrFr-OCH3 alleviated oxaliplatin-induced cold allodynia, while intramuscular injection reduced forelimb grip strength, consistent with muscle relaxant activity. Together, these findings identify WrFr-OCH3 as the shortest high-activity peptide ligand of human nAChRs reported to date, with therapeutic potential for both inflammatory pain management and muscle relaxation.

Parkinson’s disease (PD) involves motor and cognitive impairment that nicotinic acetylcholine receptors (nAChRs) such as the α7 subtype are responsible for regulating. The hippocampus, abundant in α7 nAChRs, was quantitatively evaluated for [125I]α-bungarotoxin ([125I]α-Bgtx) binding to α7 nAChRs in postmortem human PD (n = 26; 12 male, 14 female) and cognitively normal (CN) (n = 29; 14 male, 15 female) brain slices. Anti-ubiquitin and anti-α-synuclein immunostained adjacent slices were analyzed using QuPath. Autoradiographs of [125I]α-Bgtx radioligand binding were analyzed in OptiQuant. Ubiquitin and α-synuclein distribution generally aligned with the distribution of α7 nAChRs detected by [125I]α-Bgtx. Binding of [125I]α-Bgtx in PD cases was significantly greater than CN with a 32% increase in gray matter binding. A weak positive correlation between age and [125I]α-Bgtx binding was found in both PD and CN. In comparison to Alzheimer’s disease hippocampus, [125I]α-Bgtx binding in PD gray matter was higher by 41%. Differences in nAChR expression imply unique roles depending on the neurodegenerative pathology. PD may experience an increase in α7 nAChRs as a compensatory mechanism to the loss in neurons, highlighting its neuroprotective capabilities. [125I]α-Bgtx shows potential as a radioligand for α7 nAChRs to elucidate the complexities of PD pathology.

Neonicotinoid pesticides (NNs) are widely used for their selective toxicity to insects via an agonistic action on nicotinic acetylcholine receptors. However, growing evidence suggests that NNs may have adverse health effects in mammals. In parallel, recent studies have shown that trace environmental chemicals such as antibiotics, endocrine disruptors, and pesticide residues can alter the gut microbiota, a key regulator of host health. Thus, NNs may also disrupt gut microbial homeostasis and impact host physiology. In this study, we investigated the effect of the neonicotinoid pesticide clothianidin (CLO) on the rat gut microbiota. Male rats were orally administered CLO at 0, 30, and 300 mg/kg/day (designated as the CLO-0, 30, and 300 groups) for 28 days; doses were selected based on the no-observed-adverse-effect level (NOAEL; 27.9 mg/kg/day). Cecal contents were collected after euthanasia and subjected to 16S rRNA sequencing. Our results showed that even at approximately the NOAEL dose, CLO exposure altered gut microbiota composition and tended to reduce microbial diversity, especially in the CLO-300 group. Notably, several CLO-affected taxa are known producers of short-chain fatty acids, and changes were particularly prominent in two individuals from the high-dose group. Moreover, CLO exposure resulted in distinct alterations in butyrate-producing bacteria, with increases observed in the CLO-30 group and decreases in the CLO-300 group. These results suggest that CLO has various effects on the gut microbiota and that even exposure at the NOAEL may affect host health.

Chlorogenic acid (CGA) is a dietary polyphenol with well-documented anti-inflammatory property. However, its effects on cholinergic signaling during inflammation remain under-explored. To investigate the role of CGA in modulating lipopolysaccharide (LPS) induced inflammation and epithelial barrier dysfunction in human intestinal cells, with a focus on cholinergic pathways involving acetylcholinesterase (AChE) and muscarinic receptors. Caco-2 cell monolayers were treated with LPS, with or without CGA. Inflammatory markers, tight junction proteins, mucin secretion, and cholinergic gene expression were assessed via qRT-PCR, ELISA, immunofluorescence, and Alcian Blue staining. AChE activity was measured in cell supernatants. Kinetic studies were done with pure human and electric eel enzymes. Inhibition kinetics and molecular docking was performed. Darifenacin was used to probe the role of muscarinic receptors. CGA significantly suppressed LPS-induced expression of TNF-α, IL-6, and COX-2, and restored tight junction protein expression (ZO-1, occludin) and sucrase-isomaltase mRNA levels. CGA attenuated LPS-induced mucin hypersecretion without affecting MUC2 gene or protein expression. It also reversed LPS-induced upregulation of α7 nicotinic ACh receptors and further elevated choline acetyltransferase (ChAT) and M3 muscarinic receptor (mAChR3) expression. These effects were abolished by muscarinic receptor antagonism, indicating CGA's dependence on mAChR signaling. CGA reduced cholinesterase activity in supernatants. Kinetic studies revealed that CGA competitively inhibited HuAChE (IC₅₀ = 225 nM; Ki = 30.7 nM) and EeAChE (IC₅₀ = 150 µM; Ki = 15.5 µM). Molecular docking showed strong interactions with HuAChE catalytic residues and the mAChR3 orthosteric site, supporting its dual role as an AChE inhibitor and muscarinic receptor agonist. Bioavailability radar analysis confirmed CGA's potential as a drug-like molecule. CGA protects intestinal epithelial cells from inflammatory damage by enhancing cholinergic anti-inflammatory signaling through specific AChE inhibition and regulation. Future studies should validate these effects in vivo and confirm functional receptor activation and bioavailability.

Mast cell (MC)-nerve units are one of the main elements of cooperation between the nervous and immune systems, providing a structural and functional connection between MCs and autonomic nerve fibers. Although immunoregulatory activity of acetylcholine (ACh) is well established, the exact point of its influence on MCs remains unclear. This study compared the effects of muscarinic (mAChR) versus nicotinic (nAChR) ACh receptor binding on secretory activity of HMC-1 cells. It was found that ACh activates intact MCs mainly through the M3 mAChR, but suppresses degranulation in stimulated MCs via the α7 nAChR. The findings indicate that changes in the receptor pattern within MC-nerve units underlie the dual effects of ACh and enable MCs to switch functions in inflammation from proinflammatory activity in the acute phase to anti-inflammatory activity during reparation.

Association of baseline acetylcholine receptor antibody levels with efgartigimod treatment efficacy for patients with myasthenia gravis.

Positive allosteric modulation of M1 mAChRs with VU0486846 reverses cognitive deficits in male APPswe/PSEN1ΔE9 alzheimer's mice.

Crosstalk between M1 muscarinic acetylcholine receptor and endocannabinoid system promotes attenuation of inflammation in ulcerative colitis.

Neuroendocrine transcriptomics in Eriocheir sinensis: Photoperiod-induced modulation of gonadal development and circadian clock genes in neural tissues.

miR-125a-5p regulates Treg function by targeting Foxp3 in experimental autoimmune myasthenia gravis mice.

Target identification and mechanism of action of the neonicotinoid Cycloxaprid.

Efficacy and safety of an alpha 7-nicotinic acetylcholine receptor agonist, VQW-765, in subjects with performance anxiety: randomised, double-blind, placebo-controlled trial: commentary, Baldwin et al.

β-Nicotyrine and e-cigarette abuse liability I: Pharmacodynamics and interaction with pharmacokinetics and discriminative stimulus effects of nicotine in rats.

Presynaptic GABAA receptors control integration of nicotinic input onto dopaminergic axons in the striatum.

Cell membranes present barriers to the intracellular delivery of therapeutic agents. This impediment is frequently exacerbated by the hydrophobic characteristics of many such molecules, ultimately reducing the efficiency of their cellular uptake and therapeutic effectiveness. Therapeutics are being created that exploit natural bypass mechanisms by forming complexes with cell-penetrating peptides (CPPs) derived from viruses. However, current CPPs lack the ability to selectively target precise cellular macromolecules. As a result, they are distributed broadly and cause off-target side effects. Neurotropic CPPs derived from the rabies virus glycoprotein (RVG) can access the brain by binding to plasma membrane targets, including, but not exclusively, nicotinic acetylcholine receptors (nAChRs). To overcome this barrier of minimal target selectivity, we designed several chimeric peptides composed of regions from the RVG and α-bungarotoxin, an α7 subtype-selective protein. Using human nAChRs expressed in Xenopus laevis oocytes, we screened the selectivity of our peptides using two-electrode voltage clamp electrophysiology. We identified a peptide with improved α7 nAChR subtype selectivity and apparent potency compared to the control RVG peptide. Using mammalian Neuro-2a cells, we demonstrated that our peptide depends on α7 nAChR plasma membrane expression to internalize and carry small-molecule payloads into neuronal-like cells without significant cytotoxic effects. Our novel α7 nAChR subtype-selective CPP may be useful in research applications requiring cargo delivery. Translationally, our α7 nAChR-selective CPP holds potential to be a dual drug delivery system to transport cargo into the brain for the treatment of neurological diseases.

Michael Raftery was an Irish-born scientist who spent most of his career in the USA, where he made substantial and innovative contributions to the understanding of the structure and function of important proteins. Early in his career, he identified effective methods for determining the sequence of amino acids which form the building blocks of all proteins. In parallel, he carried out nuclear magnetic resonance spectroscopy experiments on an enzyme, lysozyme; this natural antibiotic breaks down the walls of bacteria by attacking the sugar–amino acids from which the wall is structured. He also studied the essential oxygen-transporting protein haemoglobin. In the 1970s, his interests turned to the acetylcholine receptor (AChR), the muscle membrane protein that is essential for receiving the chemical signal acetylcholine, required for transmission of impulses from the motor nerve to muscle. He purified the protein, demonstrated that it had four distinct but evolutionarily related subunits and, by obtaining the sequence of amino acids, allowed construction of the first cDNA probes that led to the cloning of the genes for this protein. Similarly, he purified the voltage-gated sodium channel, responsible for the conduction of the nerve impulses, and contributed to the cloning of this essential membrane ion channel. In 1971, Raftery was awarded the Doctor of Science degree from the National University of Ireland in recognition of his outstanding early research contributions, followed by Doctor of Laws in 1987. He was elected to the Royal Society in 1986.

Objective This study aimed to investigate the clinical characteristics of patients with myasthenia gravis (MG) who are double-seropositive for acetylcholine receptor antibodies (AChR-Ab + ) and titin antibodies (Titin-Ab + ). Methods A retrospective analysis was conducted on MG patients hospitalized in the Department of Neurology between March 2020 and June 2024. Patients were categorized into two groups based on antibody profiles: those with AChR antibody positivity alone and those with dual positivity for AChR and titin antibodies. Clinical features, MG classification, and treatment outcomes were compared between the two groups. Results A total of 35 MG patients were included, comprising 18 with single AChR-Ab + and 17 with AChR-Ab + /Titin-Ab + . The dual antibody-positive group showed a significantly higher proportion of patients with MGFA classification above Class II (47.1%) and a higher rate of thyroid dysfunction (50%) compared to the single antibody-positive group ( p = 0.001). The median age of onset in the dual antibody-positive group was older than that in the single antibody-positive group (67.0 years vs. 58.5 years), although this difference was not statistically significant ( p > 0.05). No significant differences were observed between the two groups in terms of gender, initial symptoms, clinical manifestations, thymic hyperplasia, proportion of thymoma, treatment regimens, or therapeutic outcomes (all p > 0.05). Conclusion This study provides the first systematic characterization of the clinical profile of AChR-Ab + /Titin-Ab + myasthenia gravis patients in Southwest China. Our findings indicate that dual antibody-positive MG patients are more prone to generalized disease involvement and have a higher susceptibility to thyroid dysfunction.

Abstract Myasthenia gravis (MG) is an autoimmune disorder driven by pathogenic IgG autoantibodies, leading to muscle weakness and impaired quality of life. Conventional immunosuppressant therapies are often limited by side effects and incomplete efficacy. Nipocalimab‐aahu (N‐a), recently FDA‐approved, is a novel neonatal Fc receptor (FcRn) antagonist that reduces circulating IgG levels, targeting the underlying disease mechanism. This review synthesizes evidence on N‐a's efficacy, safety, and clinical positioning. Phase 2 and 3 trials (Vivacity‐MG/MG3) demonstrated that N‐a significantly improves the Myasthenia Gravis Activities of Daily Living (MG‐ADL) score compared to placebo, with a favorable safety profile. The most common adverse events were nasopharyngitis and headache, with no increased serious infection risk or clinically significant hypoalbuminemia. Compared to other biologics, N‐a offers a distinct mechanism, selective IgG reduction without broad immunosuppression and a convenient bi‐weekly dosing regimen. While it shows promise for reduced systemic immunosuppression and potentially greater efficacy in MG‐ADL improvement than some alternatives, cross‐trial comparisons are limited. Key limitations include the need for long‐term safety data and more research in underrepresented populations, including pediatric and seronegative patients. In conclusion, N‐a represents a significant advancement in generalized MG (gMG) treatment, providing a targeted, effective, and well‐tolerated option that addresses a key unmet need for patients with acetylcholine receptor (AChR) or muscle‐specific kinase (MuSK) antibody‐positive disease.