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Internal Medicine (Tokyo, Japan) Jun 2024An 86-year-old woman was admitted to our hospital with cryptogenic progressive dyspnea and dysphagia following a tracheostomy procedure 4 months prior to presentation....
An 86-year-old woman was admitted to our hospital with cryptogenic progressive dyspnea and dysphagia following a tracheostomy procedure 4 months prior to presentation. She exhibited fluctuating diplopia, bilateral vocal fold paralysis, normal nerve test results, negative findings for serum anti-acetylcholine receptor and anti-muscle-specific kinase antibodies, and positive findings for anti-LDL-receptor related protein 4 (LRP4). A videofluoroscopic swallowing study (VFSS) with edrophonium revealed an improvement in bulbar paralysis. Consequently, the patient was diagnosed with double-seronegative myasthenia gravis (DSN-MG) and began immunomodulatory therapy. This case emphasizes the diagnostic challenges of bulbar-type DSN-MG and underscores the value of a VFSS with edrophonium for diagnosing this condition.
PubMed: 38897960
DOI: 10.2169/internalmedicine.3348-23 -
BioRxiv : the Preprint Server For... Jun 2024Mapping neurotransmitter identities to neurons is key to understanding information flow in a nervous system. It also provides valuable entry points for studying the...
Mapping neurotransmitter identities to neurons is key to understanding information flow in a nervous system. It also provides valuable entry points for studying the development and plasticity of neuronal identity features. In the nervous system, neurotransmitter identities have been largely assigned by expression pattern analysis of neurotransmitter pathway genes that encode neurotransmitter biosynthetic enzymes or transporters. However, many of these assignments have relied on multicopy reporter transgenes that may lack relevant -regulatory information and therefore may not provide an accurate picture of neurotransmitter usage. We analyzed the expression patterns of 16 CRISPR/Cas9-engineered knock-in reporter strains for all main types of neurotransmitters in (glutamate, acetylcholine, GABA, serotonin, dopamine, tyramine, and octopamine) in both the hermaphrodite and the male. Our analysis reveals novel sites of expression of these neurotransmitter systems within both neurons and glia, as well as non-neural cells. The resulting expression atlas defines neurons that may be exclusively neuropeptidergic, substantially expands the repertoire of neurons capable of co-transmitting multiple neurotransmitters, and identifies novel neurons that uptake monoaminergic neurotransmitters. Furthermore, we also observed unusual co-expression patterns of monoaminergic synthesis pathway genes, suggesting the existence of novel monoaminergic transmitters. Our analysis results in what constitutes the most extensive whole-animal-wide map of neurotransmitter usage to date, paving the way for a better understanding of neuronal communication and neuronal identity specification in .
PubMed: 38895397
DOI: 10.1101/2023.12.24.573258 -
BioRxiv : the Preprint Server For... Jun 2024Cholinergic receptor activation enables the persistent firing of cortical pyramidal neurons, providing a key cellular basis for theories of spatial navigation involving...
Cholinergic receptor activation enables the persistent firing of cortical pyramidal neurons, providing a key cellular basis for theories of spatial navigation involving working memory, path integration, and head direction encoding. The granular retrosplenial cortex (RSG) is important for spatially-guided behaviors, but how acetylcholine impacts RSG neurons is unknown. Here, we show that a transcriptomically, morphologically, and biophysically distinct RSG cell-type - the low-rheobase (LR) neuron - has a very distinct expression profile of cholinergic muscarinic receptors compared to all other neighboring excitatory neuronal subtypes. LR neurons do not fire persistently in response to cholinergic agonists, in stark contrast to all other principal neuronal subtypes examined within the RSG and across midline cortex. This lack of persistence allows LR neuron models to rapidly compute angular head velocity (AHV), independent of cholinergic changes seen during navigation. Thus, LR neurons can consistently compute AHV across brain states, highlighting the specialized RSG neural codes supporting navigation.
PubMed: 38895393
DOI: 10.1101/2024.06.04.597341 -
CNS Neuroscience & Therapeutics Jun 2024We aimed to compare the efficacy of tocilizumab with conventional immunotherapy in refractory patients with acetylcholine receptor antibody-positive (AChR-Ab+)...
BACKGROUND
We aimed to compare the efficacy of tocilizumab with conventional immunotherapy in refractory patients with acetylcholine receptor antibody-positive (AChR-Ab+) generalized myasthenia gravis (gMG).
METHODS
This single-center prospective cohort study was based on patients from an MG registry study in China and conducted from February 10, 2021 to March 31, 2022. Adult refractory patients with AChR-Ab+ gMG were assigned to tocilizumab or conventional immunotherapy groups. The primary efficacy outcome was the mean difference of MG activities of daily living (MG-ADL) change at weeks 4, 8, 12, 16, 20, 24 corresponding to that at the baseline between the two groups. A generalized estimating equation model was used for the primary outcome analysis. Safety was assessed based on adverse events.
RESULTS
Of 34 eligible patients, 20 (mean [standard deviation] age, 53.8 [21.9] years; 12 [60.0%] female) received tocilizumab and 14 received conventional immunotherapy (45.8 [18.0] years; 8 [57.1%] female). The tocilizumab group had greater reduction in MG-ADL score at week 4 (adjusted mean difference, -3.4; 95% CI, -4.7 to -2.0; p < 0.001) than the conventional immunotherapy group, with significant differences sustained through week 24 (adjusted mean difference, -4.5; 95% CI, -6.4 to -2.6; p < 0.001). At week 24, the proportion of patients achieving higher levels of MG-ADL (up to 7-point reduction) and QMG (up to 11-point reduction) scores improvement was significantly greater with tocilizumab. Tocilizumab had acceptable safety profiles without severe or unexpected safety issues.
CONCLUSION
Tocilizumab is safe and effective in improving the MG-ADL score and reducing prednisone dose in refractory AChR-Ab+ gMG, suggesting tocilizumab has the potential to be a valuable therapeutic option for such patients.
Topics: Humans; Antibodies, Monoclonal, Humanized; Female; Middle Aged; Male; Myasthenia Gravis; Adult; Aged; Prospective Studies; Treatment Outcome; Cohort Studies; Activities of Daily Living; Immunotherapy; Registries
PubMed: 38894580
DOI: 10.1111/cns.14793 -
Nutrients May 2024We previously demonstrated that diet supplementation with seaweed () prevented AD-related pathology in a mouse model of Alzheimer's Disease (AD). Here, we tested a...
We previously demonstrated that diet supplementation with seaweed () prevented AD-related pathology in a mouse model of Alzheimer's Disease (AD). Here, we tested a lipid extract of seaweed () and a supercritical fluid (SCF) extract of that is free of excess inorganic arsenic. Diet supplementation with extract prevented cognitive deterioration in APPswePS1ΔE9 mice. Similar trends were observed for the SCF extract. The cerebral amyloid-β plaque load remained unaffected. However, IHC analysis revealed that both extracts lowered glial markers in the brains of APPswePS1ΔE9 mice. While cerebellar cholesterol concentrations remained unaffected, both extracts increased desmosterol, an endogenous LXR agonist with anti-inflammatory properties. Both extracts increased cholesterol efflux, and particularly, extract decreased the production of pro-inflammatory cytokines in LPS-stimulated THP-1-derived macrophages. Additionally, our findings suggest a reduction of AD-associated phosphorylated tau and promotion of early oligodendrocyte differentiation by . RNA sequencing on the hippocampus of one-week-treated APPswePS1ΔE9 mice revealed effects of on, amongst others, acetylcholine and synaptogenesis signaling pathways. In conclusion, extracts of and show potential to reduce AD-related pathology in APPswePS1ΔE9 mice. Increasing desmosterol concentrations may contribute to these effects by dampening neuroinflammation.
Topics: Animals; Alzheimer Disease; Disease Models, Animal; Dietary Supplements; Seaweed; Mice; Hippocampus; Plant Extracts; Mice, Transgenic; Sargassum; Humans; Plaque, Amyloid; Cholesterol; Male; Amyloid beta-Protein Precursor; tau Proteins
PubMed: 38892548
DOI: 10.3390/nu16111614 -
International Journal of Molecular... May 2024Binge alcohol consumption during adolescence can produce lasting deficits in learning and memory while also increasing the susceptibility to substance use disorders. The...
Binge alcohol consumption during adolescence can produce lasting deficits in learning and memory while also increasing the susceptibility to substance use disorders. The adolescent intermittent ethanol (AIE) rodent model mimics human adolescent binge drinking and has identified the nucleus basalis magnocellularis (NbM) as a key site of pathology. The NbM is a critical regulator of prefrontal cortical (PFC) cholinergic function and attention. The cholinergic phenotype is controlled pro/mature neurotrophin receptor activation. We sought to determine if p75NTR activity contributes to the loss of cholinergic phenotype in AIE by using a p75NTR modulator (LM11A-31) to inhibit prodegenerative signaling during ethanol exposure. Male and female rats underwent 5 g/kg ethanol (AIE) or water (CON) exposure following 2-day-on 2-day-off cycles from postnatal day 25-57. A subset of these groups also received a protective dose of LM11A-31 (50 mg/kg) during adolescence. Rats were trained on a sustained attention task (SAT) and behaviorally relevant acetylcholine (ACh) activity was recorded in the PFC with a fluorescent indicator (AChGRAB 3.0). AIE produced learning deficits on the SAT, which were spared with LM11A-31. In addition, PFC ACh activity was blunted by AIE, which LM11A-31 corrected. Investigation of NbM ChAT+ and TrkA+ neuronal expression found that AIE led to a reduction of ChAT+TrkA+ neurons, which again LM11A-31 protected. Taken together, these findings demonstrate the p75NTR activity during AIE treatment is a key regulator of cholinergic degeneration.
Topics: Animals; Cholinergic Neurons; Rats; Male; Acetylcholine; Female; Ethanol; Prefrontal Cortex; Atrophy; Behavior, Animal; Receptors, Nerve Growth Factor; Rats, Sprague-Dawley; Disease Models, Animal; Nerve Tissue Proteins; Receptors, Growth Factor
PubMed: 38891978
DOI: 10.3390/ijms25115792 -
International Journal of Molecular... May 2024Stress exposure worsens allergic inflammatory diseases substantially. Mast cells (MCs) play a key role in peripheral immune responses to neuroendocrine stress mediators...
Stress exposure worsens allergic inflammatory diseases substantially. Mast cells (MCs) play a key role in peripheral immune responses to neuroendocrine stress mediators such as nerve growth factor (NGF) and substance P (SP). Mast cell proteases (MCPs) and cholinergic factors (Chrna7, SLURP1) were recently described to modulate MC stress response. We studied MCPs and Chrna7/SLURP1 and their interplay in a mouse model for noise induced stress (NiS) and atopic dermatitis-like allergic inflammation (AlD) and in cultured MC lacking Chrna7. We found that the cholinergic stress axis interacts with neuroendocrine stress mediators and stress-mediator cleaving enzymes in AlD. SP-cleaving mMCP4+ MC were upregulated in AlD and further upregulated by stress in NiS+AlD. Anti-NGF neutralizing antibody treatment blocked the stress-induced upregulation in vivo, and mMCP4+ MCs correlated with measures of AlD disease activity. Finally, high mMCP4 production in response to SP depended on Chrna7/SLURP1 in cultured MCs. In conclusion, mMCP4 and its upstream regulation by Chrna7/SLURP1 are interesting novel targets for the treatment of allergic inflammation and its aggravation by stress.
Topics: Animals; Mast Cells; Dermatitis, Atopic; Mice; Disease Models, Animal; Skin; alpha7 Nicotinic Acetylcholine Receptor; Inflammation; Peptide Hydrolases; Urokinase-Type Plasminogen Activator; Substance P; Stress, Physiological; Mice, Inbred C57BL; Nerve Growth Factor
PubMed: 38891925
DOI: 10.3390/ijms25115738 -
International Journal of Molecular... May 2024Organophosphoate (OP) chemicals are known to inhibit the enzyme acetylcholinesterase (AChE). Studying OP poisoning is difficult because common small animal research...
Organophosphoate (OP) chemicals are known to inhibit the enzyme acetylcholinesterase (AChE). Studying OP poisoning is difficult because common small animal research models have serum carboxylesterase, which contributes to animals' resistance to OP poisoning. Historically, guinea pigs have been used for this research; however, a novel genetically modified mouse strain (KIKO) was developed with nonfunctional serum carboxylase (Es1 KO) and an altered acetylcholinesterase (AChE) gene, which expresses the amino acid sequence of the human form of the same protein (AChE KI). KIKO mice were injected with 1xLD of an OP nerve agent or vehicle control with or without atropine. After one to three minutes, animals were injected with 35 mg/kg of the currently fielded Reactivator countermeasure for OP poisoning. Postmortem brains were imaged on a Bruker RapifleX ToF/ToF instrument. Data confirmed the presence of increased acetylcholine in OP-exposed animals, regardless of treatment or atropine status. More interestingly, we detected a small amount of Reactivator within the brain of both exposed and unexposed animals; it is currently debated if reactivators can cross the blood-brain barrier. Further, we were able to simultaneously image acetylcholine, the primary affected neurotransmitter, as well as determine the location of both Reactivator and acetylcholine in the brain. This study, which utilized sensitive MALDI-MSI methods, characterized KIKO mice as a functional model for OP countermeasure development.
Topics: Animals; Organophosphate Poisoning; Mice; Disease Models, Animal; Humans; Acetylcholinesterase; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Atropine; Brain; Mice, Knockout; Cholinesterase Inhibitors; Acetylcholine
PubMed: 38891812
DOI: 10.3390/ijms25115624 -
Plants (Basel, Switzerland) May 2024This study aimed to evaluate the spasmolytic activity of an underground parts extract of L. (Gentianaceae), assess its antioxidant and antimicrobial activities, and...
This study aimed to evaluate the spasmolytic activity of an underground parts extract of L. (Gentianaceae), assess its antioxidant and antimicrobial activities, and explore the impact of extract encapsulation on the aforementioned bioactivities. An extract encapsulated by spray drying with whey protein, pure extract, and pure whey protein were comparatively tested. The main compounds identified via HPLC-DAD analysis underwent in silico ADME assessment. The spasmolytic effect was tested on a model of spontaneous rat ileum contractions, and the mechanism of action was further evaluated on acetylcholine-, KCl-, CaCl-, BaCl-, histamine-, N()-nitro-L-arginine methyl ester-, and glibenclamide-modified contractions. The most abundant compounds were secoiridoids (dominantly gentiopicroside), followed by -glycosylated flavonoids and xanthones. Both pure and encapsulated extracts achieved significant spasmolytic effects, despite the spasmogenic activity of pure whey protein. The extract may exert its spasmolytic effect through multiple pathways, predominantly by antagonizing the Ca channel and opening the K channel, while the nitric oxide pathway appears not to be involved. The antimicrobial and antioxidant activities of the pure extract were moderate. The extract stabilized by encapsulation retained all of the tested bioactivities of the unencapsulated extract. The obtained results suggest that has potential for use in the treatment of some gastrointestinal complaints and that the encapsulated extract could be a valuable functional ingredient in pharmaceutical and food products.
PubMed: 38891254
DOI: 10.3390/plants13111445 -
Acta Neuropathologica Jun 2024Myasthenia gravis is a chronic antibody-mediated autoimmune disease disrupting neuromuscular synaptic transmission. Informative biomarkers remain an unmet need to...
Myasthenia gravis is a chronic antibody-mediated autoimmune disease disrupting neuromuscular synaptic transmission. Informative biomarkers remain an unmet need to stratify patients with active disease requiring intensified monitoring and therapy; their identification is the primary objective of this study. We applied mass spectrometry-based proteomic serum profiling for biomarker discovery. We studied an exploration and a prospective validation cohort consisting of 114 and 140 anti-acetylcholine receptor antibody (AChR-Ab)-positive myasthenia gravis patients, respectively. For downstream analysis, we applied a machine learning approach. Protein expression levels were confirmed by ELISA and compared to other myasthenic cohorts, in addition to myositis and neuropathy patients. Anti-AChR-Ab levels were determined by a radio receptor assay. Immunohistochemistry and immunofluorescence of intercostal muscle biopsies were employed for validation in addition to interactome studies of inter-alpha-trypsin inhibitor heavy chain H3 (ITIH3). Machine learning identified ITIH3 as potential serum biomarker reflective of disease activity. Serum levels correlated with disease activity scores in the exploration and validation cohort and were confirmed by ELISA. Lack of correlation between anti-AChR-Ab levels and clinical scores underlined the need for biomarkers. In a subgroup analysis, ITIH3 was indicative of treatment responses. Immunostaining of muscle specimens from these patients demonstrated ITIH3 localization at the neuromuscular endplates in myasthenia gravis but not in controls, thus providing a structural equivalent for our serological findings. Immunoprecipitation of ITIH3 and subsequent proteomics lead to identification of its interaction partners playing crucial roles in neuromuscular transmission. This study provides data on ITIH3 as a potential pathophysiological-relevant biomarker of disease activity in myasthenia gravis. Future studies are required to facilitate translation into clinical practice.
Topics: Humans; Myasthenia Gravis; Biomarkers; Male; Female; Middle Aged; Adult; Aged; Autoantibodies; Receptors, Cholinergic; Proteomics; Cohort Studies; Young Adult; Proteinase Inhibitory Proteins, Secretory; Machine Learning
PubMed: 38888758
DOI: 10.1007/s00401-024-02754-6