ABSTRACT
Acetylcholine (Ach) is a common neurotransmitter in the central nervous system (CNS) and peripheral nervous system (PNS). It is one of the neurotransmitters in the autonomic nervous system and the main neurotransmitter in all autonomic ganglia. Experiments have confirmed that electromagnetic waves can affect the synthesis of animal neurotransmitters, but the microscopic effects of electromagnetic waves in the terahertz (THz) frequency band are still unclear. Based on density functional theory (DFT) and molecular dynamics (MD) simulation methods, this paper studies the effect of THz electromagnetic waves on the binding of choline to choline acetyltransferase (ChAT). By emitting THz waves that resonate with the characteristic vibration mode of choline near the active site, it was found that THz waves with a frequency of 45.3 THz affected the binding of choline to ChAT, especially the binding of the active site histidine His324 to choline. The main evidence is that under the action of THz waves, the binding free energy of choline to histidine His324 and ChAT at the active site was significantly reduced compared to noE, which may have a potential impact on the enzymatic synthesis of Ach. It is expected to achieve the purpose of regulating the synthesis of the neurotransmitter Ach under the action of THz waves and treat certain nervous system diseases.
Subject(s)
Choline O-Acetyltransferase , Choline , Molecular Dynamics Simulation , Choline O-Acetyltransferase/metabolism , Choline O-Acetyltransferase/chemistry , Choline/metabolism , Choline/chemistry , Terahertz Radiation , Catalytic Domain , Protein Binding , Density Functional Theory , Binding Sites , Acetylcholine/metabolism , Acetylcholine/chemistry , ThermodynamicsABSTRACT
Cholinergic signaling is essential to mediate the auditory prepulse inhibition (PPI), an operational measure of sensorimotor gating, that refers to the reduction of the acoustic startle reflex (ASR) when a low-intensity, non-startling acoustic stimulus (the prepulse) is presented just before the onset of the acoustic startle stimulus. The cochlear root neurons (CRNs) are the first cells of the ASR circuit to receive cholinergic inputs from non-olivocochlear neurons of the ventral nucleus of the trapezoid body (VNTB) and subsequently decrease their neuronal activity in response to auditory prepulses. Yet, the contribution of the VNTB-CRNs pathway to the mediation of PPI has not been fully elucidated. In this study, we used the immunotoxin anti-choline acetyltransferase (ChAT)-saporin as well as electrolytic lesions of the medial olivocochlear bundle to selectively eliminate cholinergic VNTB neurons, and then assessed the ASR and PPI paradigms. Retrograde track-tracing experiments were conducted to precisely determine the site of lesioning VNTB neurons projecting to the CRNs. Additionally, the effects of VNTB lesions and the integrity of the auditory pathway were evaluated via auditory brain responses tests, ChAT- and FOS-immunohistochemistry. Consequently, we established three experimental groups: 1) intact control rats (non-lesioned), 2) rats with bilateral lesions of the olivocochlear bundle (OCB-lesioned), and 3) rats with bilateral immunolesions affecting both the olivocochlear bundle and the VNTB (OCB/VNTB-lesioned). All experimental groups underwent ASR and PPI tests at several interstimulus intervals before the lesion and 7, 14, and 21 days after it. Our results show that the ASR amplitude remained unaffected both before and after the lesion across all experimental groups, suggesting that the VNTB does not contribute to the ASR. The%PPI increased across the time points of evaluation in the control and OCB-lesioned groups but not in the OCB/VNTB-lesioned group. At the ISI of 50 ms, the OCB-lesioned group exhibited a significant increase in%PPI (p < 0.01), which did not occur in the OCB/VNTB-lesioned group. Therefore, the ablation of cholinergic non-olivocochlear neurons in the OCB/VNTB-lesioned group suggests that these neurons contribute to the mediation of auditory PPI at the 50 ms ISI through their cholinergic projections to CRNs. Our study strongly reinforces the notion that auditory PPI encompasses a complex mechanism of top-down cholinergic modulation, effectively attenuating the ASR across different interstimulus intervals within multiple pathways.
Subject(s)
Acoustic Stimulation , Auditory Pathways , Prepulse Inhibition , Reflex, Startle , Trapezoid Body , Animals , Prepulse Inhibition/physiology , Male , Trapezoid Body/metabolism , Trapezoid Body/physiology , Auditory Pathways/physiology , Auditory Pathways/metabolism , Rats, Sprague-Dawley , Saporins/metabolism , Choline O-Acetyltransferase/metabolism , Cholinergic Neurons/metabolism , Cholinergic Neurons/physiology , Ribosome Inactivating Proteins, Type 1 , Evoked Potentials, Auditory, Brain Stem , Immunotoxins , Cochlear Nerve/metabolism , Cochlear Nerve/physiology , RatsABSTRACT
It has been reported that the clinical symptoms of functional dyspepsia (FD) exacerbate upon stress while the gender-related factors have been incompletely understood. This study aims to investigate the role of sex in chronic heterotypic stress (CHS)-induced autonomic and gastric motor dysfunction. For CHS, the rats were exposed to the combination of different stressors for 7 consecutive days. Subsequently, electrocardiography was recorded in anesthetized rats to evaluate heart rate variability (HRV) for the determination of autonomic outflow and sympathovagal balance. Solid gastric emptying (GE) was measured in control and CHS-loaded male and female rats. The immunoreactivities of catecholaminergic cell marker tyrosine hydroxylase (TH), choline acetyltransferase (ChAT), corticotropin releasing factor (CRF), and estrogen receptor (ER-α/ß) were evaluated in medullary and pontine brainstem sections by immunohistochemistry. Compared with the controls, CHS significantly delayed GE in males but not in females. There was no significant sex-related difference in parasympathetic indicator HF under either control or CHS conditions. Sympathetic indicator LF was significantly higher in control females compared to the males. The higher sympathetic output in females was found to be attenuated upon CHS; in contrast, the elevated sympathetic output was detected in CHS-loaded males. No sex- or stress-related effect was observed on ChAT immunoreactivity in the dorsal motor nucleus of N.vagus (DMV). In males, greater number of TH-ir cells was observed in the caudal locus coeruleus (LC), while they were more densely detected in the rostral LC of females. Regardless of sex, CHS elevated immunoreactivity of TH throughout the LC. Under basal conditions, greater number of TH-ir cells was detected in the rostral ventrolateral medulla (RVLM) of females. In contrast, CHS remarkably increased the number of TH-ir cells in the RVLM of males which was found to be decreased in females. There was no sex-related alteration in TH immunoreactivity in the nucleus tractus solitarius (NTS) of control rats, while CHS affected both sexes in a similar manner. Compared with females, CRF immunoreactivity was prominently observed in control males, while both of which were stimulated by CHS. ER-α/ß was found to be co-expressed with TH in the NTS and LC which exhibit no alteration related to either sex or stress status. These results indicate a sexual dimorphism in the catecholaminergic and the CRF system in brainstem which might be involved in the CHS-induced autonomic and visceral dysfunction occurred in males.
Subject(s)
Rats, Sprague-Dawley , Sex Characteristics , Stress, Psychological , Animals , Male , Female , Stress, Psychological/metabolism , Stress, Psychological/physiopathology , Rats , Rhombencephalon/metabolism , Gastrointestinal Motility/physiology , Catecholamines/metabolism , Tyrosine 3-Monooxygenase/metabolism , Autonomic Nervous System/physiopathology , Autonomic Nervous System/metabolism , Heart Rate/physiology , Corticotropin-Releasing Hormone/metabolism , Gastric Emptying/physiology , Choline O-Acetyltransferase/metabolismABSTRACT
This study investigated the effects of cilostazol on motor dysfunction, spinal motor neuron abnormalities, and schwannopathy in rats with diabetes. Diabetes mellitus (DM) was induced in rats via femoral intravenous streptozotocin (STZ) injection (60 mg/kg). After successful DM induction, cilostazol was administered on day 15 via oral gavage (100 mg/kg/day) for 6 weeks until sacrifice. Behavioral assays, including motor function, were performed weekly. The sciatic nerve, L5 spinal cord, and spinal ventral root were collected to evaluate the expression of the glial fibrillary acidic protein (GFAP), myelin protein zero (P0), and choline acetyltransferase (ChAT) by immunofluorescence and Western blotting. DM rats displayed decreased running speeds, running distances, and toe spread but increased foot pressure. In addition, loss of non-myelinating Schwann cells and myelin sheaths was observed in the sciatic nerve and L5 spinal ventral root. Reduced numbers of motor neurons were also found in the L5 spinal ventral horn. Cilostazol administration significantly potentiated running speed and distance; increased hind paw toe spread; and decreased foot pressure. In the sciatic nerve and L5 spinal ventral root, cilostazol treatment significantly improved non-myelinated Schwann cells and increased myelin mass. ChAT expression in motor neurons in the spinal ventral horn was improved, but not significantly. Cilostazol administration may protect sensorimotor function in diabetic rats.
Subject(s)
Cilostazol , Diabetes Mellitus, Experimental , Schwann Cells , Sciatic Nerve , Animals , Cilostazol/pharmacology , Cilostazol/therapeutic use , Schwann Cells/drug effects , Schwann Cells/metabolism , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/metabolism , Rats , Male , Sciatic Nerve/drug effects , Sciatic Nerve/metabolism , Choline O-Acetyltransferase/metabolism , Rats, Sprague-Dawley , Spinal Cord/drug effects , Spinal Cord/metabolism , Motor Neurons/drug effects , Motor Neurons/metabolism , Glial Fibrillary Acidic Protein/metabolism , Myelin P0 Protein/metabolism , StreptozocinABSTRACT
The non-neural cholinergic system plays a critical role in regulating immune equilibrium and tissue homeostasis. While the expression of choline acetyltransferase (ChAT), the enzyme catalyzing acetylcholine biosynthesis, has been well documented in lymphocytes, its role in the myeloid compartment is less understood. Here, we identify a significant population of macrophages (MÏs) expressing ChAT and synthesizing acetylcholine in the resolution phase of acute peritonitis. Using Chat-GFP reporter mice, we observed marked upregulation of ChAT in monocyte-derived small peritoneal MÏs (SmPMs) in response to Toll-like receptor agonists and bacterial infections. These SmPMs, phenotypically and transcriptionally distinct from tissue-resident large peritoneal macrophages, up-regulated ChAT expression through a MyD88-dependent pathway involving MAPK signaling. Notably, this process was attenuated by the TRIF-dependent TLR signaling pathway, and our tests with a range of neurotransmitters and cytokines failed to induce a similar response. Functionally, Chat deficiency in MÏs led to significantly decreased peritoneal acetylcholine levels, reduced efferocytosis of apoptotic neutrophils, and a delayed resolution of peritonitis, which were reversible with exogenous ACh supplementation. Intriguingly, despite B lymphocytes being a notable ChAT-expressing population within the peritoneal cavity, Chat deletion in B cells did not significantly alter the resolution process. Collectively, these findings underscore the crucial role of MÏ-derived acetylcholine in the resolution of inflammation and highlight the importance of the non-neuronal cholinergic system in immune regulation.
Subject(s)
Acetylcholine , Choline O-Acetyltransferase , Macrophages, Peritoneal , Peritonitis , Animals , Choline O-Acetyltransferase/metabolism , Choline O-Acetyltransferase/genetics , Peritonitis/immunology , Peritonitis/metabolism , Mice , Macrophages, Peritoneal/metabolism , Macrophages, Peritoneal/immunology , Acetylcholine/metabolism , Myeloid Differentiation Factor 88/metabolism , Myeloid Differentiation Factor 88/genetics , Mice, Inbred C57BL , Signal Transduction , Inflammation/metabolism , Inflammation/pathology , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Toll-Like Receptors/metabolism , Phagocytosis , Macrophages/metabolism , Macrophages/immunology , Mice, KnockoutABSTRACT
Methamphetamine (METH) withdrawal anxiety symptom and relapse have been significant challenges for clinical practice, however, the underlying neuronal basis remains unclear. Our recent research has identified a specific subpopulation of choline acetyltransferase (ChAT+) neurons localized in the external lateral portion of parabrachial nucleus (eLPBChAT), which modulates METH primed-reinstatement of conditioned place preference (CPP). Here, the anatomical structures and functional roles of eLPBChAT projections in METH withdrawal anxiety and primed reinstatement were further explored. Methods: In the present study, a multifaceted approach was employed to dissect the LPBChAT+ projections in male mice, including anterograde and retrograde tracing, acetylcholine (Ach) indicator combined with fiber photometry recording, photogenetic and chemogenetic regulation, as well as electrophysiological recording. METH withdrawal anxiety-like behaviors and METH-primed reinstatement of conditioned place preference (CPP) were assessed in male mice. Results: We identified that eLPBChAT send projections to PKCδ-positive (PKCδ+) neurons in lateral portion of central nucleus of amygdala (lCeAPKCδ) and oval portion of bed nucleus of the stria terminalis (ovBNSTPKCδ), forming eLPBChAT-lCeAPKCδ and eLPBChAT-ovBNSTPKCδ pathways. At least in part, the eLPBChAT neurons positively innervate lCeAPKCδ neurons and ovBNSTPKCδ neurons through regulating synaptic elements of presynaptic Ach release and postsynaptic nicotinic acetylcholine receptors (nAChRs). METH withdrawal anxiety and METH-primed reinstatement of CPP respectively recruit eLPBChAT-lCeAPKCδ pathway and eLPBChAT-ovBNSTPKCδ pathway in male mice. Conclusion: Our findings put new insights into the complex neural networks, especially focusing on the eLPBChAT projections. The eLPBChAT is a critical node in the neural networks governing METH withdrawal anxiety and primed-reinstatement of CPP through its projections to the lCeAPKCδ and ovBNSTPKCδ, respectively.
Subject(s)
Anxiety , Methamphetamine , Mice, Inbred C57BL , Substance Withdrawal Syndrome , Animals , Methamphetamine/adverse effects , Male , Mice , Substance Withdrawal Syndrome/metabolism , Substance Withdrawal Syndrome/physiopathology , Anxiety/metabolism , Neurons/metabolism , Choline O-Acetyltransferase/metabolism , Septal Nuclei/metabolism , Behavior, Animal/drug effectsABSTRACT
Dysregulation of oligodendrocyte progenitor cell (OPC) recruitment and oligodendrocyte differentiation contribute to failure of remyelination in human demyelinating diseases such as multiple sclerosis (MS). Deletion of muscarinic receptor enhances OPC differentiation and remyelination. However, the role of ligand-dependent signaling versus constitutive receptor activation is unknown. We hypothesized that dysregulated acetylcholine (ACh) release upon demyelination contributes to ligand-mediated activation hindering myelin repair. Following chronic cuprizone (CPZ)-induced demyelination (male and female mice), we observed a 2.5-fold increase in ACh concentration. This increase in ACh concentration could be attributed to increased ACh synthesis or decreased acetylcholinesterase-/butyrylcholinesterase (BChE)-mediated degradation. Using choline acetyltransferase (ChAT) reporter mice, we identified increased ChAT-GFP expression following both lysolecithin and CPZ demyelination. ChAT-GFP expression was upregulated in a subset of injured and uninjured axons following intraspinal lysolecithin-induced demyelination. In CPZ-demyelinated corpus callosum, ChAT-GFP was observed in Gfap+ astrocytes and axons indicating the potential for neuronal and astrocytic ACh release. BChE expression was significantly decreased in the corpus callosum following CPZ demyelination. This decrease was due to the loss of myelinating oligodendrocytes which were the primary source of BChE. To determine the role of ligand-mediated muscarinic signaling following lysolecithin injection, we administered neostigmine, a cholinesterase inhibitor, to artificially raise ACh. We identified a dose-dependent decrease in mature oligodendrocyte density with no effect on OPC recruitment. Together, these results support a functional role of ligand-mediated activation of muscarinic receptors following demyelination and suggest that dysregulation of ACh homeostasis directly contributes to failure of remyelination in MS.
Subject(s)
Demyelinating Diseases , Oligodendroglia , Signal Transduction , Animals , Demyelinating Diseases/metabolism , Demyelinating Diseases/chemically induced , Demyelinating Diseases/pathology , Mice , Oligodendroglia/metabolism , Oligodendroglia/drug effects , Female , Male , Signal Transduction/drug effects , Signal Transduction/physiology , Mice, Inbred C57BL , Acetylcholine/metabolism , Cuprizone/toxicity , Lysophosphatidylcholines/toxicity , Cell Differentiation/drug effects , Cell Differentiation/physiology , Choline O-Acetyltransferase/metabolism , Remyelination/physiology , Remyelination/drug effects , Myelin Sheath/metabolism , Myelin Sheath/drug effects , Mice, TransgenicABSTRACT
Upon parasitic helminth infection, activated intestinal tuft cells secrete interleukin-25 (IL-25), which initiates a type 2 immune response during which lamina propria type 2 innate lymphoid cells (ILC2s) produce IL-13. This causes epithelial remodeling, including tuft cell hyperplasia, the function of which is unknown. We identified a cholinergic effector function of tuft cells, which are the only epithelial cells that expressed choline acetyltransferase (ChAT). During parasite infection, mice with epithelial-specific deletion of ChAT had increased worm burden, fitness, and fecal egg counts, even though type 2 immune responses were comparable. Mechanistically, IL-13-amplified tuft cells release acetylcholine (ACh) into the gut lumen. Finally, we demonstrated a direct effect of ACh on worms, which reduced their fecundity via helminth-expressed muscarinic ACh receptors. Thus, tuft cells are sentinels in naive mice, and their amplification upon helminth infection provides an additional type 2 immune response effector function.
Subject(s)
Acetylcholine , Intestinal Mucosa , Animals , Acetylcholine/metabolism , Mice , Intestinal Mucosa/immunology , Intestinal Mucosa/metabolism , Intestinal Mucosa/parasitology , Choline O-Acetyltransferase/metabolism , Interleukin-13/metabolism , Interleukin-13/immunology , Mice, Knockout , Mice, Inbred C57BL , Helminthiasis/immunology , Helminthiasis/parasitology , Epithelial Cells/immunology , Epithelial Cells/metabolism , Immunity, Innate , Nematospiroides dubius/immunology , Tuft CellsABSTRACT
People frequently face decisions that require making inferences about withheld information. The advent of large language models coupled with conversational technology, e.g., Alexa, Siri, Cortana, and the Google Assistant, is changing the mode in which people make these inferences. We demonstrate that conversational modes of information provision, relative to traditional digital media, result in more critical responses to withheld information, including: (1) a reduction in evaluations of a product or service for which information is withheld and (2) an increased likelihood of recalling that information was withheld. These effects are robust across multiple conversational modes: a recorded phone conversation, an unfolding chat conversation, and a conversation script. We provide further evidence that these effects hold for conversations with the Google Assistant, a prominent conversational technology. The experimental results point to participants' intuitions about why the information was withheld as the driver of the effect.
Subject(s)
Communication , Internet , Humans , Language , Technology , Choline O-AcetyltransferaseABSTRACT
The present study aimed to examine the effect of cholinergic interneuron lesions in the dorsal striatum on duration-memory formation. Cholinergic interneurons in the dorsal striatum may be involved in the formation of duration memory since they are among the main inputs to the dorsal striatal muscarinic acetylcholine-1 receptors, which play a role in the consolidation of duration memory. Rats were sufficiently trained using a peak-interval 20 s procedure and then infused with anti-choline acetyltransferase-saporin into the dorsal striatum to cause selective ablation of cholinergic interneurons. To make the rats acquire new duration-memories, we trained them with a peak interval 40 s after lesion. Before lesion, the peak times (an index of duration memory) for sham-lesioned and lesioned groups were similar at approximately 20 s. In the peak interval 40 s session, the peak times for the sham-lesioned and lesioned groups were approximately 30 and 20 s, respectively. After additional peak interval 40 s sessions, the peak times of both groups were shifted to approximately 40 s. Those results suggest that the cholinergic interneuron lesion delayed new duration-memory acquisition. Subsequent experiments showed that cholinergic interneuron lesions did not retard the shift of peak time to the original target time (20 s). Following experiment without changing the target time after lesion showed that cholinergic interneuron lesions did not change their peak times. Our findings suggest that cholinergic interneurons in the dorsal striatum are involved in new duration-memory acquisition but not in the utilization of already acquired duration memory and interval timing.
Subject(s)
Cholinergic Neurons , Corpus Striatum , Interneurons , Animals , Interneurons/physiology , Male , Rats , Corpus Striatum/physiology , Cholinergic Neurons/physiology , Cholinergic Neurons/metabolism , Memory/physiology , Choline O-Acetyltransferase/metabolism , Rats, WistarABSTRACT
Health equity and accessing Spanish kidney transplant information continues being a substantial challenge facing the Hispanic community. This study evaluated ChatGPT's capabilities in translating 54 English kidney transplant frequently asked questions (FAQs) into Spanish using two versions of the AI model, GPT-3.5 and GPT-4.0. The FAQs included 19 from Organ Procurement and Transplantation Network (OPTN), 15 from National Health Service (NHS), and 20 from National Kidney Foundation (NKF). Two native Spanish-speaking nephrologists, both of whom are of Mexican heritage, scored the translations for linguistic accuracy and cultural sensitivity tailored to Hispanics using a 1-5 rubric. The inter-rater reliability of the evaluators, measured by Cohen's Kappa, was 0.85. Overall linguistic accuracy was 4.89 ± 0.31 for GPT-3.5 versus 4.94 ± 0.23 for GPT-4.0 (non-significant p = 0.23). Both versions scored 4.96 ± 0.19 in cultural sensitivity (p = 1.00). By source, GPT-3.5 linguistic accuracy was 4.84 ± 0.37 (OPTN), 4.93 ± 0.26 (NHS), 4.90 ± 0.31 (NKF). GPT-4.0 scored 4.95 ± 0.23 (OPTN), 4.93 ± 0.26 (NHS), 4.95 ± 0.22 (NKF). For cultural sensitivity, GPT-3.5 scored 4.95 ± 0.23 (OPTN), 4.93 ± 0.26 (NHS), 5.00 ± 0.00 (NKF), while GPT-4.0 scored 5.00 ± 0.00 (OPTN), 5.00 ± 0.00 (NHS), 4.90 ± 0.31 (NKF). These high linguistic and cultural sensitivity scores demonstrate Chat GPT effectively translated the English FAQs into Spanish across systems. The findings suggest Chat GPT's potential to promote health equity by improving Spanish access to essential kidney transplant information. Additional research should evaluate its medical translation capabilities across diverse contexts/languages. These English-to-Spanish translations may increase access to vital transplant information for underserved Spanish-speaking Hispanic patients.
Subject(s)
Kidney Transplantation , Humans , Alanine Transaminase , Artificial Intelligence , Choline O-Acetyltransferase , Health Promotion , Hispanic or Latino , Reproducibility of Results , State Medicine , Mexican AmericansABSTRACT
PURPOSE: As the elderly population grows, the prevalence of dementia is also rapidly increasing worldwide. Metformin, an antidiabetic drug, has been shown to have ameliorative effects on impaired cognitive functions in experimental models. However, studies have generally used young animals. Additionally, although it has a major role in Alzheimer's disease (AD) and memory, literature information about the effects of metformin on the cholinergic system is limited. In this study, we investigated the effects of metformin on memory in a model of scopolamine-induced memory impairment in aged rats. We also examined the effects of metformin on the cholinergic system, which is very important in cognitive functions. METHODS: Metformin was administered orally to male Wistar rats (20-22 months old) at 100â¯mg/kg/day for three weeks. Morris water maze (MWM) tests were performed to assess spatial memory. Before the probe test of the MWM test, scopolamine was injected intraperitoneally at a dose of 1â¯mg/kg. After testing, animals were sacrificed, whole brains were removed, and hippocampus samples were separated for biochemical analysis. RESULTS: Impaired memory associated with scopolamine administration was reversed by metformin. In addition, metformin administration ameliorated scopolamine-induced changes in acetylcholine (ACh) levels, acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), and choline acetyltransferase (ChAT) activity. CONCLUSION: Our results show that metformin may have protective effects in a scopolamine-induced memory impairment model in aged animals by improving cholinergic function. Metformin shows promise in preventing dementia with its dual cholinesterase inhibition and ChAT activation effect.
Subject(s)
Acetylcholine , Aging , Choline O-Acetyltransferase , Disease Models, Animal , Hippocampus , Memory Disorders , Metformin , Rats, Wistar , Scopolamine , Animals , Metformin/pharmacology , Metformin/administration & dosage , Scopolamine/pharmacology , Male , Memory Disorders/chemically induced , Memory Disorders/drug therapy , Rats , Choline O-Acetyltransferase/metabolism , Hippocampus/drug effects , Hippocampus/metabolism , Aging/drug effects , Acetylcholine/metabolism , Acetylcholinesterase/metabolism , Maze Learning/drug effects , Hypoglycemic Agents/pharmacology , Spatial Memory/drug effectsABSTRACT
The auditory cortex is the source of descending connections providing contextual feedback for auditory signal processing at almost all levels of the lemniscal auditory pathway. Such feedback is essential for cognitive processing. It is likely that corticofugal pathways are degraded with aging, becoming important players in age-related hearing loss and, by extension, in cognitive decline. We are testing the hypothesis that surface, epidural stimulation of the auditory cortex during aging may regulate the activity of corticofugal pathways, resulting in modulation of central and peripheral traits of auditory aging. Increased auditory thresholds during ongoing age-related hearing loss in the rat are attenuated after two weeks of epidural stimulation with direct current applied to the surface of the auditory cortex for two weeks in alternate days (Fernández del Campo et al., 2024). Here we report that the same cortical electrical stimulation protocol induces structural and cytochemical changes in the aging cochlea and auditory brainstem, which may underlie recovery of age-degraded auditory sensitivity. Specifically, we found that in 18 month-old rats after two weeks of cortical electrical stimulation there is, relative to age-matched non-stimulated rats: a) a larger number of choline acetyltransferase immunoreactive neuronal cell body profiles in the ventral nucleus of the trapezoid body, originating the medial olivocochlear system.; b) a reduction of age-related dystrophic changes in the stria vascularis; c) diminished immunoreactivity for the pro-inflammatory cytokine TNFα in the stria vascularis and spiral ligament. d) diminished immunoreactivity for Iba1 and changes in the morphology of Iba1 immunoreactive cells in the lateral wall, suggesting reduced activation of macrophage/microglia; d) Increased immunoreactivity levels for calretinin in spiral ganglion neurons, suggesting excitability modulation by corticofugal stimulation. Altogether, these findings support that non-invasive neuromodulation of the auditory cortex during aging preserves the cochlear efferent system and ameliorates cochlear aging traits, including stria vascularis dystrophy, dysregulated inflammation and altered excitability in primary auditory neurons.
Subject(s)
Aging , Auditory Cortex , Auditory Pathways , Cochlea , Electric Stimulation , Presbycusis , Animals , Male , Age Factors , Aging/pathology , Aging/metabolism , Auditory Cortex/metabolism , Auditory Cortex/physiopathology , Auditory Pathways/physiopathology , Auditory Pathways/metabolism , Auditory Threshold , Calcium-Binding Proteins , Choline O-Acetyltransferase/metabolism , Cochlea/innervation , Cochlea/metabolism , Cochlea/physiopathology , Cochlea/pathology , Disease Models, Animal , Evoked Potentials, Auditory, Brain Stem , Hearing , Microfilament Proteins , Microglia/metabolism , Microglia/pathology , Neurons, Efferent/metabolism , Olivary Nucleus/metabolism , Presbycusis/physiopathology , Presbycusis/metabolism , Presbycusis/pathology , Rats, Wistar , Tumor Necrosis Factor-alpha/metabolismABSTRACT
The gastrointestinal (GI) tract is innervated by intrinsic neurons of the enteric nervous system (ENS) and extrinsic neurons of the central nervous system and peripheral ganglia. The GI tract also harbors a diverse microbiome, but interactions between the ENS and the microbiome remain poorly understood. Here, we activate choline acetyltransferase (ChAT)-expressing or tyrosine hydroxylase (TH)-expressing gut-associated neurons in mice to determine effects on intestinal microbial communities and their metabolites as well as on host physiology. The resulting multi-omics datasets support broad roles for discrete peripheral neuronal subtypes in shaping microbiome structure, including modulating bile acid profiles and fungal colonization. Physiologically, activation of either ChAT+ or TH+ neurons increases fecal output, while only ChAT+ activation results in increased colonic contractility and diarrhea-like fluid secretion. These findings suggest that specific subsets of peripherally activated neurons differentially regulate the gut microbiome and GI physiology in mice without involvement of signals from the brain.
Subject(s)
Gastrointestinal Microbiome , Neurons , Animals , Gastrointestinal Microbiome/physiology , Mice , Neurons/metabolism , Choline O-Acetyltransferase/metabolism , Enteric Nervous System/physiology , Mice, Inbred C57BL , Tyrosine 3-Monooxygenase/metabolism , Male , Gastrointestinal Tract/microbiologyABSTRACT
The chatbot Chat Generative Pretrained Transformer (ChatGPT) is becoming increasingly popular among patients for searching health-related information. Prior studies have raised concerns regarding accuracy in offering nutritional advice. We investigated in November 2023 ChatGPT's potential as a tool for providing nutritional guidance in relation to different non-communicable diseases (NCDs). First, the dietary advice given by ChatGPT (version 3.5) for various NCDs was compared with guidelines; then, the chatbot's capacity to manage a complex case with several diseases was investigated. A panel of nutrition experts assessed ChatGPT's responses. Overall, ChatGPT offered clear advice, with appropriateness of responses ranging from 55.5% (sarcopenia) to 73.3% (NAFLD). Only two recommendations (one for obesity, one for non-alcoholic-fatty-liver disease) contradicted guidelines. A single suggestion for T2DM was found to be "unsupported", while many recommendations for various NCDs were deemed to be "not fully matched" to the guidelines despite not directly contradicting them. However, when the chatbot handled overlapping conditions, limitations emerged, resulting in some contradictory or inappropriate advice. In conclusion, although ChatGPT exhibited a reasonable accuracy in providing general dietary advice for NCDs, its efficacy decreased in complex situations necessitating customized strategies; therefore, the chatbot is currently unable to replace a healthcare professional's consultation.
Subject(s)
Non-alcoholic Fatty Liver Disease , Noncommunicable Diseases , Humans , Health Education , Choline O-Acetyltransferase , Health Facilities , Noncommunicable Diseases/prevention & controlABSTRACT
The enzyme choline acetyltransferase (ChAT) synthesizes acetylcholine from acetyl-CoA and choline at the neuromuscular junction and at the nerve terminals of cholinergic neurons. Mutations in the ChAT gene (CHAT) result in a presynaptic congenital myasthenic syndrome (CMS) that often associates with life-threatening episodes of apnea. Knockout mice for Chat (Chat-/-) die at birth. To circumvent the lethality of this model, we crossed mutant mice possessing loxP sites flanking Chat exons 4 and 5 with mice that expressed Cre-ERT2. Injection of tamoxifen (Tx) at postnatal (P) day 11 in these mice induced downregulation of Chat, autonomic failure, weakness, and death. However, a proportion of Chatflox/flox-Cre-ERT2 mice receiving at birth an intracerebroventricular injection of 2 × 1013 vg/kg adeno-associated virus type 9 (AAV9) carrying human CHAT (AAV9-CHAT) survived a subsequent Tx injection and lived to adulthood without showing signs of weakness. Likewise, injection of AA9-CHAT by intracisternal injection at P28 after the onset of weakness also resulted in survival to adulthood. The expression of Chat in spinal motor neurons of Chatflox/flox-Cre-ERT2 mice injected with Tx was markedly reduced, but AAV-injected mice showed a robust recovery of ChAT expression, which was mainly translated by the human CHAT RNA. The biodistribution of the viral genome was widespread but maximal in the spinal cord and brain of AAV-injected mice. No significant histopathological changes were observed in the brain, liver, and heart of AAV-injected mice after 1 year follow-up. Thus, AAV9-mediated gene therapy may provide an effective and safe treatment for patients severely affected with CHAT-CMS.
Subject(s)
Choline O-Acetyltransferase , Dependovirus , Mice , Humans , Animals , Choline O-Acetyltransferase/genetics , Choline O-Acetyltransferase/metabolism , Dependovirus/genetics , Dependovirus/metabolism , Tissue Distribution , Mice, Knockout , Genetic TherapyABSTRACT
BACKGROUND: Doxorubicin (DOX) may cause various neurological side effects in the brain. Lercanidipine (LRD) has antioxidant, anti-inflammatory, and anti-apoptotic properties. The aim of this study was to investigate the potential benefits of. METHODS AND RESULTS: Lercanidipine in reducing doxorubicin-induced neuroinflammation and maintaining the expressions of choline acetyltransferase. Thirty-two adult Wistar albino female rats were divided into four groups as Control, DOX (20 mg/kg intraperitoneally), DOX + LRD 0.5 (0.5 mg/kg orally), and DOX + LRD2(2 mg/kg orally). Twenty-four hours after the last drug administration (9th day), brain tissues were taken for histopathological, immunohistochemical (choline acetyltransferase [CHAT], interleukin-10 [IL-10], and caspase-3 [Cas-3] staining), biochemical (total antioxidant status [TAS], total oxidant status [TOS], and oxidative stress index [OSI]), and genetic analyzes (PI3K/AKT/HIF1-α and IL-6 gene expressions). Histopathological analyses revealed hyperemia, slight hemorrhage, degeneration, neuronal loss, gliosis in the cerebellum, and neuronal loss in the brain cortex and hippocampus in the DOX group. According to other analyzes, decreased CHAT, PI3K, AKT, HIF1-α and increased IL-6, IL-10, Cas-3 expression were observed in the DOX group. CONCLUSIONS: Both LRD doses reversed all these findings, but LRD2 was observed to be more effective. In conclusion, we determined that LRD has potential therapeutic effect by reducing DOX-induced neuroinflammation, oxidative stress and apoptosis in brain tissues.
Subject(s)
Choline O-Acetyltransferase , Dihydropyridines , Interleukin-10 , Animals , Rats , Rats, Wistar , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Antioxidants/pharmacology , Interleukin-6 , Neuroinflammatory Diseases , Doxorubicin/adverse effectsABSTRACT
BACKGROUND: Generative Artificial Intelligence (AI) technology, for instance Chat Generative Pre-trained Transformer (ChatGPT), is continuously evolving, and its userbase is growing. These technologies are now being experimented by the businesses to leverage their potential and minimise their risks in business operations. The continuous adoption of the emerging Generative AI technologies will help startups gain more and more experience with adoptions, helping them to leverage continuously evolving technological innovation landscape. However, there is a dearth of prior research on ChatGPT adoption in the startup context, especially from Entrepreneur perspective, highlights the urgent need for a thorough investigation to identify the variables influencing this technological adoption. The primary objective of this study is to ascertain the factors that impact the uptake of ChatGPT technology by startups, anticipate their influence on the triumph of companies, and offer pragmatic suggestions for various stakeholders, including entrepreneurs, and policymakers. METHOD AND ANALYSIS: This study attempts to explore the variables impacting startups' adoption of ChatGPT technology, with an emphasis on comprehending entrepreneurs' attitudes and perspectives. To identify and then empirically validate the Generative AI technology adoption framework, the study uses a two-stage methodology that includes experience-based research, and survey research. The research method design is descriptive and Correlational design. Stage one of the research study is descriptive and involves adding practical insights, and real-world context to the model by drawing from the professional consulting experiences of the researchers with the SMEs. The outcome of this stage is the adoption model (also called as research framework), building Upon Technology Adoption Model (TAM), that highlight the technology adoption factors (also called as latent variables) connected with subset of each other and finally to the technology adoption factor (or otherwise). Further, the latent variables and their relationships with other latent variables as graphically highlighted by the adoption model will be translated into the structured questionnaire. Stage two involves survey based research. In this stage, structured questionnaire is tested with small group of entrepreneurs (who has provided informed consent) and finally to be distributed among startup founders to further validate the relationships between these factors and the level of influence individual factors have on overall technology adoption. Partial Least Squares Structural Equation Modeling (PLS-SEM) will be used to analyze the gathered data. This multifaceted approach allows for a comprehensive analysis of the adoption process, with an emphasis on understanding, describing, and correlating the key elements at play. DISCUSSION: This is the first study to investigate the factors that impact the adoption of Generative AI, for instance ChatGPT technology by startups from the Entrepreneurs perspectives. The study's findings will give Entrepreneurs, Policymakers, technology providers, researchers, and Institutions offering support for entrepreneurs like Academia, Incubators and Accelerators, University libraries, public libraries, chambers of commerce, and foreign embassies important new information that will help them better understand the factors that encourage and hinder ChatGPT adoption. This will allow them to make well-informed strategic decisions about how to apply and use this technology in startup settings thereby improving their services for businesses.
Subject(s)
Artificial Intelligence , Technology , Humans , Biological Transport , Choline O-Acetyltransferase , CommerceABSTRACT
We examined the presence/absence and parcellation of cholinergic neurons in the hypothalami of five birds: a Congo grey parrot (Psittacus erithacus), a Timneh grey parrot (P. timneh), a pied crow (Corvus albus), a common ostrich (Struthio camelus), and an emu (Dromaius novaehollandiae). Using immunohistochemistry to an antibody raised against the enzyme choline acetyltransferase, hypothalamic cholinergic neurons were observed in six distinct clusters in the medial, lateral, and ventral hypothalamus in the parrots and crow, similar to prior observations made in the pigeon. The expression of cholinergic nuclei was most prominent in the Congo grey parrot, both in the medial and lateral hypothalamus. In contrast, no evidence of cholinergic neurons in the hypothalami of either the ostrich or emu was found. It is known that the expression of sleep states in the ostrich is unusual and resembles that observed in the monotremes that also lack hypothalamic cholinergic neurons. It has been proposed that the cholinergic system acts globally to produce and maintain brain states, such as those of arousal and rapid-eye-movement sleep. The hiatus in the cholinergic system of the ostrich, due to the lack of hypothalamic cholinergic neurons, may explain, in part, the unusual expression of sleep states in this species. These comparative anatomical and sleep studies provide supportive evidence for global cholinergic actions and may provide an important framework for our understanding of one broad function of the cholinergic system and possible dysfunctions associated with global cholinergic neural activity.
Subject(s)
Dromaiidae , Struthioniformes , Animals , Dromaiidae/metabolism , Struthioniformes/metabolism , Brain/metabolism , Hypothalamus/metabolism , Cholinergic Neurons/metabolism , Sleep/physiology , Cholinergic Agents , Choline O-Acetyltransferase/metabolismABSTRACT
BACKGROUND: The use of artificial intelligence (AI) in medicine not only directly impacts the medical profession but is also increasingly associated with various potential ethical aspects. In addition, the expanding use of AI and AI-based applications such as ChatGPT demands a corresponding shift in medical education to adequately prepare future practitioners for the effective use of these tools and address the associated ethical challenges they present. OBJECTIVE: This study aims to explore how medical students from Germany, Austria, and Switzerland perceive the use of AI in medicine and the teaching of AI and AI ethics in medical education in accordance with their use of AI-based chat applications, such as ChatGPT. METHODS: This cross-sectional study, conducted from June 15 to July 15, 2023, surveyed medical students across Germany, Austria, and Switzerland using a web-based survey. This study aimed to assess students' perceptions of AI in medicine and the integration of AI and AI ethics into medical education. The survey, which included 53 items across 6 sections, was developed and pretested. Data analysis used descriptive statistics (median, mode, IQR, total number, and percentages) and either the chi-square or Mann-Whitney U tests, as appropriate. RESULTS: Surveying 487 medical students across Germany, Austria, and Switzerland revealed limited formal education on AI or AI ethics within medical curricula, although 38.8% (189/487) had prior experience with AI-based chat applications, such as ChatGPT. Despite varied prior exposures, 71.7% (349/487) anticipated a positive impact of AI on medicine. There was widespread consensus (385/487, 74.9%) on the need for AI and AI ethics instruction in medical education, although the current offerings were deemed inadequate. Regarding the AI ethics education content, all proposed topics were rated as highly relevant. CONCLUSIONS: This study revealed a pronounced discrepancy between the use of AI-based (chat) applications, such as ChatGPT, among medical students in Germany, Austria, and Switzerland and the teaching of AI in medical education. To adequately prepare future medical professionals, there is an urgent need to integrate the teaching of AI and AI ethics into the medical curricula.