Acetylcholine Levels Research Articles

Characterization of HCN channel subtypes at hypoglossal motoneurons throughout postnatal maturation in mice

The inspiratory phase of breathing includes a stiffening of the upper airway to decrease airway resistance and is mediated by excitatory motor output from hypoglossal motoneurons (XII MNs). This excitation decreases from wakefulness to sleep. This decrease in excitation is in large part due to increasing acetylcholine levels, which activate muscarinic acetylcholine receptors (mAChRs) that have a net inhibitory effect in adult preparations. By contrast, activation of mAChRs in neonatal rodent preparations has a net effect of potentiating inspiratory burst amplitude. Therefore, characterizing changes in muscarinic effects at XII MNs across postnatal maturation will help elucidate the mechanism underlying the shift from muscarinic excitation to inhibition. mAChRs modulate several effector ion channels including the hyperpolarization activated cyclic nucleotide gated (HCN) channel. HCN channels give rise to I h, a mixed cation current activated at hyperpolarized membrane potentials. I h additionally shows upregulation at XII MNs with postnatal maturation. Since there are four HCN subtypes (HCN1-4), the reported changes in I h may be caused by changes in HCN channel subtype levels. HCN1 and HCN2 are most prominent in adult XII MNs, whereas the expression of HCN1-4 in neonates is unknown. Thus, the purpose of this research is to characterize changes in HCN gene and channel expression levels at XII MNs across postnatal maturation. We hypothesis that both HCN1 and HCN2 subtypes will increase with postnatal maturation, and that HCN2 has higher levels than HCN1. To test this hypothesis, we used neuroanatomical techniques to evaluate changes in expression patterns of the four HCN proteins at the XII nuclei across postnatal maturation in CD-1 mice. We performed double-labeled immunofluorescence experiments against HCN1 and HCN2 and co-labeled with choline acetyltransferase (ChAT) on 20μm transverse brainstem slices across six postnatal age groups under identical conditions: P0-P1, P4-P6, P9-P10, P12-P14, P17-P19, and adult. Images of the XII nuclei were collected using a confocal microscope. ImageJ was used to determine the average XII MN HCN subtype intensity across postnatal maturation. Preliminary data suggest that HCN1 (n=2) channels undergo a decrease in expression at P17-19 before a final increase in adulthood (P0-1= 97-100%, P4-6= 92-100%, P9-10= 85-95%, P12-14= 77-97%, P17-19= 61-67%, adult= 71-82%). By contrast, preliminary data suggest that HCN2 (n=2) expression intensity remained relatively consistent with a decrease in labeling intensity at P4-6 (P0-1= 97-100%, P4-6=62-84%, P9-10= 45-95%, P12-14= 67-90%, P17-19= 50-93%, adult= 75-100%). These modest changes in labeling intensity of HCN channel subtypes may not contribute to the observed shift of mAChR modulation at XII MNs from excitation to inhibition with postnatal maturation. Biomedical Sciences, College of Graduate Studies; Department of Physiology, College of Graduate Studies, Midwestern University; NIH/NHLBI Funding: R15HL148870. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Neurotherapeutic effects of quercetin-loaded nanoparticles and Biochanin-A extracted from Trifolium alexandrinum on PI3K/Akt/GSK-3β signaling in the cerebral cortex of male diabetic rats.

Diabetes mellitus (DM) is a severe metabolic disease that can have significant consequences for cognitive health. Bioflavonoids such as Trifolium alexandrinum (TA), quercetin (Q), and Biochanin-A (BCA) are known to exert a wide range of pharmacological functions including antihyperglycemic activity. This study aimed to investigate the neurotherapeutic effects of quercetin-loaded nanoparticles (Q-LNP) and BCA extracted from TA against diabetes-induced cerebral cortical damage through modulation of PI3K/Akt/GSK-3β and AMPK signaling pathways. Adult male Wistar albino rats (N = 25) were randomly assigned to one of five groups: control, diabetics fed a high-fat diet (HFD) for 2 weeks and intraperitoneally (i.p.) injected with STZ (40 mg/kg), and diabetics treated with Q-LNP (50 mg/kg BW/day), BCA (10 mg/kg BW/day), or TA extract (200 mg/kg BW/day). Treatments were applied by oral gavage once daily for 35 days. Diabetic rats treated with Q-LNP, BCA, and TA extract showed improvement in cognitive performance, cortical oxidative metabolism, antioxidant parameters, and levels of glucose, insulin, triglyceride, and total cholesterol. In addition, these treatments improved neurochemical levels, including acetylcholine, dopamine, and serotonin levels as well acetylcholinesterase and monoamine oxidase activities. Furthermore, these treatments lowered proinflammatory cytokine production for TNF-α and NF-κB; downregulated the levels of IL-1β, iNOS, APP, and PPAR-γ; and attenuated the expressions of PSEN2, BACE, IR, PI3K, FOXO 1, AKT, AMPK, GSK-3β, and GFAP. The histopathological examinations of the cerebral cortical tissues confirmed the biochemical results. Overall, the present findings suggest the potential therapeutic effects of TA bioflavonoids in modulating diabetes-induced cerebral cortical damage.

Next-generation neonicotinoid: The impact of cycloxaprid on the crustacean decapod Penaeus vannamei

Cycloxaprid, a new neonicotinoid pesticide, poses ecological risks, particularly in aquatic environments, due to its unique action and environmental dispersal. This study investigated the ecotoxicological effects of various concentrations of cycloxaprid on Penaeus vannamei over 28 days. High cycloxaprid levels significantly altered shrimp physiology, as shown by changes in the hepatosomatic index and fattening. Indicators of oxidative stress, such as increased serum hemocyanin, respiratory burst, and nitric oxide, as well as decreased phenol oxidase activity, were observed. Additionally, elevated activities of lactate dehydrogenase, succinate dehydrogenase, and isocitrate dehydrogenase indicated disrupted energy metabolism in the hepatopancreas. Notably, analyses of the nervous system revealed marked disturbances in neural signaling, as evidenced by elevated acetylcholine, octopamine, and acetylcholinesterase levels. Transcriptomic analysis highlighted significant effects on gene expression and metabolic processes in the hepatopancreas and nervous system. This study demonstrated that cycloxaprid disrupts neural signaling and oxidative balance in P. vannamei, potentially affecting its growth, and provides key insights into its biochemical and transcriptomic toxicity in aquatic systems.

Dihalogenated nitrophenols exposure induces developmental neurotoxicity in zebrafish embryo

2,6-Dihalogenated nitrophenols (2,6-DHNPs) are emerging halogenated nitroaromatic pollutants that have been detected in various water environments. However, there is currently limited research available regarding their potential impacts on locomotion behavior and neurotoxicity. Therefore, this study utilized zebrafish embryos to investigate the potential neurotoxic effects of 2,6-DHNPs by examining their impact on the nervous system at a concentration defined as 10% of the median lethal concentration. Our findings demonstrated that exposure to 2,6-DHNPs resulted in a significant 30 % decrease in the total swimming distance of zebrafish larvae, accompanied by notable impairments in motor neuron development and central nervous system. These effects were evidenced by a substantial 25% decrease in axonal growth, as well as disruptions in synapse formation and neuronal differentiation. Additionally, neurotransmitter analysis revealed marked decreases of 40%, 35%, and 30% in dopamine, 5-hydroxytryptamine, and acetylcholine levels respectively, highlighting disturbances in their synthesis, transport, and degradation mechanisms. These results emphasize the considerable neurotoxicity of 2,6-DHNPs at concentrations previously considered safe; thus necessitating a re-evaluation of environmental risk assessments and regulatory standards for such emerging contaminants.

Amygdalar neurotransmission alterations in the BTBR mice model of idiopathic autism.

Autism Spectrum Disorders (ASD) are principally diagnosed by three core behavioural symptoms, such as stereotyped repertoire, communication impairments and social dysfunctions. This complex pathology has been linked to abnormalities of corticostriatal and limbic circuits. Despite experimental efforts in elucidating the molecular mechanisms behind these abnormalities, a clear etiopathogenic hypothesis is still lacking. To this aim, preclinical studies can be really helpful to longitudinally study behavioural alterations resembling human symptoms and to investigate the underlying neurobiological correlates. In this regard, the BTBR T+ Itpr3tf/J (BTBR) mice are an inbred mouse strain that exhibits a pattern of behaviours well resembling human ASD-like behavioural features. In this study, the BTBR mice model was used to investigate neurochemical and biomolecular alterations, regarding Nerve Growth Factor (NGF) and Brain-Derived Neurotrophic Factor (BDNF), together with GABAergic, glutamatergic, cholinergic, dopaminergic and noradrenergic neurotransmissions and their metabolites in four different brain areas, i.e. prefrontal cortex, hippocampus, amygdala and hypothalamus. In our results, BTBR strain reported decreased noradrenaline, acetylcholine and GABA levels in prefrontal cortex, while hippocampal measurements showed reduced NGF and BDNF expression levels, together with GABA levels. Concerning hypothalamus, no differences were retrieved. As regarding amygdala, we found reduced dopamine levels, accompanied by increased dopamine metabolites in BTBR mice, together with decreased acetylcholine, NGF and GABA levels and enhanced glutamate content. Taken together, our data showed that the BTBR ASD model, beyond its face validity, is a useful tool to untangle neurotransmission alterations that could be underpinned to the heterogeneous ASD-like behaviours, highlighting the crucial role played by amygdala.

Nanoplastics aggravated TDCIPP-induced transgenerational developmental neurotoxicity in zebrafish depending on the involvement of the dopamine signaling pathway

Plastics pose a hazard to the environment. Although plastics have toxicity, microplastics (MPs) and nanoplastics (NPs) are capable of interacting with the rest pollutants in the environment, so they serve as the carriers and interact with organic pollutants to modulate their toxicity, thus resulting in unpredictable ecological risks. PS-NPs and TDCIPP were used expose from 2 h post-fertilization (hpf) to 150 days post-fertilization (dpf) to determine the bioaccumulation of tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and its potential effects on neurodevelopment in F1 zebrafish (Danio rerio) offspring under the action of polystyrene nano plastics (PS-NPs). The exposure groups were assigned to TDCIPP (0, 0.4, 2 or 10 µg/L) alone group and the PS-NPs (100 µg/L) and TDCIPP co-exposed group. F1 embryos were collected and grown in clean water to 5 dpf post-fertilization. PS-NPs facilitated the bioaccumulation of TDCIPP in the gut, gill, head，gonad and liver of zebrafish in a sex-dependent manner and promoted the transfer of TDCIPP to their offspring, thus contributing to PS-NPs aggravated the inhibition of offspring development and neurobehavior of TDCIPP-induced. In comparison with TDCIPP exposure alone, the combination could notably down-regulate the levels of the dopamine neurotransmitter, whereas the levels of serotonin or acetylcholine were not notably different. This result was achieved probably because PS-NPs interfered with the TDCIPP neurotoxic response of zebrafish F1 offspring not through the serotonin or acetylcholine neurotransmitter pathway. The increased transfer of TDCIPP to the offspring under the action of PS-NPs increased TDCIPP-induced transgenerational developmental neurotoxicity, which was proven by a further up-regulation/down-regulation the key gene and protein expression related to dopamine synthesis, transport, and metabolism in F1 larvae, in contrast to TDCIPP exposure alone. The above findings suggested that dopaminergic signaling involvement could be conducive to the transgenerational neurodevelopmental toxicity of F1 larval upon parental early co-exposure to PS-NPs and TDCIPP.

The role of the cholinergic system in the memory-protecting effects of metformin in a model of scopolamine-induced memory impairment in aged rats

PurposeAs 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. MethodsMetformin was administered orally to male Wistar rats (20–22 months old) at 100 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 1 mg/kg. After testing, animals were sacrificed, whole brains were removed, and hippocampus samples were separated for biochemical analysis. ResultsImpaired 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. ConclusionOur 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.

Novel Phytosomal Formulation of Emblica officinalis Extracts with Its In Vivo Nootropic Potential in Rats: Optimization and Development by Box-Behnken Design

Purpose. The present study aimed to improve the aqueous solubility, permeability, bioavailability, and nootropic potential of standardized Emblica officinalis extract (EOE) by developing a novel phytosomal formulation. Method. Emblica officinalis extract-loaded phytosomes (EOPs) were prepared using solvent evaporation. The EOP was prepared at different molar ratios of extract and phospholipid. Herein, the effects of phospholipid extract ratio (A), temperature (B), and reaction time (C) were systematically investigated on entrapment efficiency using Box-Behnken design. In vitro and in vivo characterizations of the optimized formulation were performed. Results. Optimized EOP formulation (89.90 ± 0.24 μg/ml) exhibited improved aqueous solubility than plain EOE (11.85 ± 0.25 μg/ml). The optimized formulation’s particle size and Zeta potential were 198.4 ± 0.20 nm and −39.0 ± 0.40 mv. DSC and XRD studies confirmed the partial amorphization of EOE in phytosomes. Optimized formulation exhibited 69.82 ± 0.17% of EOE release at 12 h and followed zero-order release kinetics. Moreover, the phytosomal formulation of EOE exhibited its rationality with an improvement of bioavailability by 2.7 folds compared with pure EOE. Compared to EOE, EOP showed significantly (p<0.05 lower escape and transfer latencies on both days in MWMT and EPMT, indicating more effective memory-enhancing activity. Furthermore, EOP-treated rats exhibited improved acetylcholine (Ach) levels than EOE. Brain tissue concentrations measured following EOP oral administration (1.06 ± 0.04 μg/ml) were substantially greater (p<0.05) than those following EOE (0.32 ± 0.07 μg/ml). The brain dopamine and serotonin concentration were found to be higher (16.27 ± 1.209 and 43.28 ± 1.550 ng/ml) in the EOP-treated group as compared to the pure extract-treated group (10.40 ± 1.185 and 32.79 ± 1.738 ng/ml). Conclusion. Improvement of aqueous solubility, permeability, dissolution, bioavailability, and narrower particle size distribution could facilitate enhancement in the nootropic potential of EOE phytosomal formulation.

Inhibition of calcium-sensing receptor by its antagonist promotes gastrointestinal motility in a Parkinson’s disease mouse model

BackgroundThe Calcium-sensing receptor (CaSR) participates in the regulation of gastrointestinal (GI) motility under normal conditions and might be involved in the regulation of GI dysmotility in patients with Parkinson's disease (PD). MethodsCaSR antagonist-NPS-2143 was applied in in vivo and ex vivo experiments to study the effect and underlying mechanisms of CaSR inhibition on GI dysmotility in the MPTP-induced PD mouse model. FindingsOral intake of NPS-2143 promoted GI motility in PD mice as shown by the increased gastric emptying rate and shortened whole gut transit time together with improved weight and water content in the feces of PD mice, and the lack of influence on normal mice. Meanwhile, the number of cholinergic neurons, the proportion of serotonergic neurons, as well as the levels of acetylcholine and serotonin increased, but the numbers of nitrergic and tyrosine hydroxylase immunoreactive neurons, and the levels of nitric oxide synthase and dopamine decreased in the myenteric plexus in the gastric antrum and colon of PD mice in response to NPS-2143 treatment. Furthermore, the numbers of c-fos positive neurons in the nucleus tractus solitarius (NTS) and cholinergic neurons in the dorsal motor nucleus of the vagus (DMV) increased in NPS-2143 treated PD mice, suggesting the involvement of both the enteric (ENS) and central (CNS) nervous systems. However, ex vivo results showed that NPS-2143 directly inhibited the contractility of antral and colonic strips in PD mice via a non-ENS mediated mechanism. Further studies revealed that NPS-2143 directly inhibited the voltage gated Ca2+ channels, which might, at least in part, explain its direct inhibitory effects on the GI muscle strips. InterpretationCaSR inhibition by its antagonist ameliorated GI dysmotility in PD mice via coordinated neuronal regulation by both ENS and CNS in vivo, although the direct effects of CaSR inhibition on GI muscle strips were suppressive.

196 Quantifying Cholinergic Cortical Response to Deep Brain Stimulation in Murine Models

INTRODUCTION: Deep brain stimulation has become a potential treatment for mental disorders. We have previously documented that chronic, one-hour daily, intermittent stimulation of the basal forebrain causes increases in cortical levels of acetylcholine and demonstrates improvement in working memory behavior in monkeys and mice. Continuous stimulation, in contrast, appears to deplete releasable acetylcholine in roughly one minute (Blake et al., Brain Stimulation, 2023; 16(1): 364). This study serves as the first quantification of cortical acetylcholine response to stimulation. METHODS: Viral vectors encoding cell surface receptors fluorescent to acetylcholine are injected into superficial cortex in mice through a small craniotomy. After three weeks, the craniotomy is enlarged for glass window affixation above the injection site. Electrodes are implanted posteriorly and angled to contact the basal forebrain. Cortical expression of acetylcholine in response to stimulation is visualized via two-photon microscopy through the window and quantified over time. RESULTS: Preliminary data suggest that the physiologic half-life of acetylcholine in the cerebral cortex is 10-12 seconds. Also, the system expressed acetylcholine at normal levels after 20 minutes following 100 seconds of 60Hz stimulation (6000 total pulses). Based on these observations, each second of 60 Hz stimulation of the basal forebrain requires 12 seconds of recovery time. CONCLUSIONS: These data are foundational for future explorations in developing treatments for pathology involving cholinergic exchange and recycling, with implications in optimizing deep brain stimulation and tailoring pharmaceuticals that augment acetylcholine reuptake. These data also suggest that high-frequency stimulation decreases neurotransmitter output through depletion. Additional experimentation in the future will incorporate acetylcholinesterase inhibitors and additional stimulation patterns to assess clinical response.

The following article for this Special Issue was previously published and can be found in its respective issue online: "How can I measure brain acetylcholine levels in vivo? Advantages and caveats of commonly used approaches".

How can I measure brain acetylcholine levels in vivo? Advantages and caveats of commonly used approaches (Published in JNC 167.1 issue) https://onlinelibrary.wiley.com/doi/10.1111/jnc.15943.

Design, Synthesis and Molecular Modeling Study of Radiotracers Based on Tacrine and Its Derivatives for Study on Alzheimer’s Disease and Its Early Diagnosis

From 1993 to 2013, tacrine was an approved drug for Alzheimer’s disease. Due to its strong inhibitory properties towards cholinesterase, tacrine causes an increase in the level of the neurotransmitter acetylcholine in the cholinergic system of the central nervous system. This work presents a review of articles in which tacrine or its derivatives labeled with the radionuclides 3H, 11C, 14C, 123I, 99mTc and 68Ga were used as vectors in radiotracers dedicated to the diagnosis of Alzheimer’s disease. The possibility of clinical applications of the obtained radiopreparations was assessed by analyzing their physicochemical properties, ability to cross the blood–brain barrier and the level of uptake in the brain. Based on these data, it was shown that radiopreparations based on the tacrine molecule or its very close analogues retain the ability to cross the blood–brain barrier, while radiopreparations containing a more modified tacrine molecule (connected via a linker to a radionuclide chelator) lose this ability. This is probably the result of the addition of a chelator, which significantly increases the size of the radiopreparation and reduces its lipophilicity. Computer docking studies of tacrine derivatives and/or radiopreparations showed how these compounds bind to the active sites of acetyl- and butyrylcholinesterase.

Novel 6-alkyl-bridged 4-arylalkylpiperazin-1-yl derivatives of azepino[4,3-b]indol-1(2H)-one as potent BChE-selective inhibitors showing protective effects against neurodegenerative insults

Due to the putative role of butyrylcholinesterase (BChE) in regulation of acetylcholine levels and functions in the late stages of the Alzheimer's disease (AD), the potential of selective inhibitors (BChEIs) has been envisaged as an alternative to administration of acetylcholinesterase inhibitors (AChEIs). Starting from our recent findings, herein the synthesis and in vitro evaluation of cholinesterase (ChE) inhibition of a novel series of some twenty 3,4,5,6-tetrahydroazepino[4,3-b]indol-1(2H)-one derivatives, bearing at the indole nitrogen diverse alkyl-bridged 4-arylalkylpiperazin-1-yl chains, are reported. The length of the spacers, as well as the type of arylalkyl group affected the enzyme inhibition potency and BChE/AChE selectivity. Two compounds, namely 14c (IC50 = 163 nM) and 14d (IC50 = 65 nM), bearing at the nitrogen atom in position 6 a n-pentyl- or n-heptyl-bridged 4-phenethylpiperazin-1-yl chains, respectively, proved to be highly potent mixed-type inhibitors of both equine and human BChE isoforms, showing more than two order magnitude of selectivity over AChE. The study of binding kinetics through surface plasmon resonance (SPR) highlighted differences in their BChE residence times (8 and 47 s for 14c and 14d, respectively). Moreover, 14c and 14d proved to hit other mechanisms known to trigger neurodegeneration underlying AD and other CNS disorders. Unlike 14c, compound 14d proved also capable of inhibiting by more than 60% the in vitro self-induced aggregation of neurotoxic amyloid-β (Aβ) peptide at 100 μM concentration. On the other hand, 14c was slightly better than 14d in counteracting, at 1 and 10 μM concentration, glutamate excitotoxicity, due to over-excitation of NMDA receptors, and hydrogen peroxide-induced oxidative stress assessed in neuroblastoma cell line SH-SY5Y. This paper is dedicated to Prof. Marcello Ferappi, former dean of the Faculty of Pharmacy of the University of Bari, in the occasion of his 90th birthday.

Overnight neuronal plasticity and adaptation to emotional distress.

Expressions such as 'sleep on it' refer to the resolution of distressing experiences across a night of sound sleep. Sleep is an active state during which the brain reorganizes thesynaptic connections that form memories. This Perspective proposes a model of how sleep modifies emotional memory traces. Sleep-dependent reorganization occurs through neurophysiological events in neurochemical contexts that determine the fates of synapses to grow, to survive or to be pruned. We discuss how low levels of acetylcholine during non-rapid eye movement sleep and low levels of noradrenaline during rapid eye movement sleep provide a unique window of opportunity for plasticity in neuronal representations of emotional memories that resolves the associated distress. We integrate sleep-facilitated adaptation over three levels: experience and behaviour, neuronal circuits, and synaptic events. The model generates testable hypotheses for how failed sleep-dependent adaptation to emotional distress is key to mental disorders, notably disorders of anxiety, depression and post-traumatic stress with the common aetiology of insomnia.

Synthesis and molecular docking studies of 5-trifluoromethoxy-2-indolinones as cholinesterase dual inhibitors.

Background: In Alzheimer's disease, butyrylcholinesterase (BuChE) activity gradually increases, while acetylcholinesterase (AChE) activity decreases or remains unchanged. Dual inhibitors have important roles in regulation of synaptic acetylcholine levels and progression of Alzheimer's disease. Methods: 1-(Thiomorpholin-4-ylmethyl)/benzyl-5-trifluoromethoxy-2-indolinones (6-7) were synthesized. AChE and BuChE inhibitory effects were investigated with Ellman's method. Molecular docking studies were performed for analyzing the possible binding interactions at active sites. Results: Compound 6g was the strongest inhibitor against both AChE (Ki=0.35μM) and BuChE (Ki=0.53μM). It showed higher inhibitory effects than both donepezil and galantamine. Moreover, compound 7m had a higher inhibitory effect than galantamine and the effect was comparable to that of donepezil against both AChE (Ki=0.69μM) and BuChE (Ki=0.95μM). Conclusion: The benzyl substitution compared with 1-(thiomorpholin-4-ylmethyl) group significantly increased both AChE and BuChE inhibitory effects.

Ondansetron attenuates cisplatin-induced behavioral and cognitive impairment through downregulation of NOD-like receptor inflammasome pathway

Cisplatin is an effective and commonly used chemotherapeutic drug; however, its use is accompanied by several adverse effects, including chemobrain. Ondansetron is a 5-HT3 antagonist, commonly used in prophylactic against chemotherapy-induced nausea and vomiting. Moreover, it has been identified as a novel neuroprotective agent in different animal models. However, its protective role against chemotherapy-induced chemobrain has not been investigated. The current study was the first study that explored the potential neuroprotective effect of ondansetron against cisplatin-induced chemobrain in rats. Cisplatin (5 mg/Kg) was injected intraperitoneally, once weekly, for 4 weeks with the daily administration of ondansetron (0.5 and 1 mg/Kg). Compared to the cisplatin-treated group, ondansetron administration showed a significant decrease in the latency time and a significant increase in ambulation, rearing, and grooming frequency in the open field test (OFT). Moreover, a significant improvement in the latency time in the rotarod and passive avoidance tests, following ondansetron administration. In addition, ondansetron treatment increased the percentage of alternation in the Y-maze test. Also, ondansetron showed a remarkable enhancement in the biochemical parameters in the hippocampus. It increased the acetylcholine (Ach) level and decreased the level of the acetylcholine esterase enzyme (AchE). Ondansetron significantly decreased interleukin-1β (Il-1β), tumor necrosis factor-alpha (TNF-α), toll-like receptor-4 (TLR-4), NOD-like receptor-3 (NLRP3) inflammasome as well as caspase-1 and caspase-3 levels. Furthermore, ondansetron significantly decreased the levels of copper transporter-1(CTR1) expression in the hippocampus. Collectively, these findings suggest that ondansetron may exhibit a neuroprotective and therapeutic activity against cisplatin-induced chemobrain.

Pyridostigmine attenuated high-fat-diet induced liver injury by the reduction of mitochondrial damage and oxidative stress via α7nAChR and M3AChR.

Obesity is a major cause of nonalcohol fatty liver disease (NAFLD), which is characterized by hepatic fibrosis, lipotoxicity, inflammation, and apoptosis. Previous studies have shown that an imbalance in the autonomic nervous system is closely related to the pathogenesis of NAFLD. In this study, we investigated the effects of pyridostigmine (PYR), a cholinesterase (AChE) inhibitor, on HFD-induced liver injury and explored the potential mechanisms involving mitochondrial damage and oxidative stress. A murine model of HFD-induced obesity was established using the C57BL/6 mice, and PYR (3 mg/kg/d) or placebo was administered for 20 weeks. PYR reduced the body weight and liver weight of the HFD-fed mice. Additionally, the serum levels of IL-6, TNF-α, cholesterol, and triglyceride were significantly lower in the PYR-treated versus the untreated mice, corresponding to a decrease in hepatic fibrosis, lipid accumulation, and apoptosis in the former. Furthermore, the mitochondrial morphology improved significantly in the PYR-treated group. Consistently, PYR upregulated ATP production and the mRNA level of the mitochondrial dynamic factors OPA1, Drp1 and Fis1, and the mitochondrial unfolded protein response (UPRmt) factors LONP1 and HSP60. Moreover, PYR treatment activated the Keap1/Nrf2 pathway and upregulated HO-1 and NQO-1, which mitigated oxidative injury as indicated by decreased 8-OHDG, MDA and H2 O2 levels, and increased SOD activity. Finally, PYR elevated acetylcholine (ACh) levels by inhibiting AChE, and upregulated the α7nAChR and M3AChR proteins in the HFD-fed mice. PYR alleviated obesity-induced hepatic injury in mice by mitigating mitochondrial damage and oxidative stress via α7nAChR and M3AChR.

Safety and efficacy of acetylcholinesterase inhibitors for Alzheimer's disease: A systematic review and meta-analysis.

Alzheimer's disease (AD) affects millions of people worldwide. The most commonly used drugs are acetylcholinesterase inhibitors, i.e., donepezil, galantamine and rivastigmine, which increase levels of acetylcholine. However, the exact efficacy and safety of acetylcholinesterase inhibitors in the treatment of AD is still unclear. The main objective of the current study was to determine the exact safety and efficacy profile of acetylcholinesterase inhibitors in the treatment of AD by conducting a systematic review and meta-analysis of clinical trials according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We conducted a web-based literature search of PubMed and clinical trial websites using relevant keywords. Data were extracted from eligible records and pooled as mean difference (MD) or risk ratio (RR) values with their 95% confidence interval (95% CI) using Review Manager software (v. 5.3 for Windows). Heterogeneity was calculated using χ2 and I2 tests. The standard mean difference (SMD) was -0.33 [-0.52, -0.13] for donepezil, -0.48 [-0.58, -0.38] for galantamine and -0.65 [-1.06, -0.23] for rivastigmine, indicating a significant effect of these drugs on cognitive outcomes. Here we show the significant effects of all available acetylcholinesterase inhibitors on cognitive function in patients with AD. However, further studies are needed to draw valid conclusions about the effects of acetylcholinesterase inhibitors on functional outcomes and adverse events.

The role of leptin in regulation of the soluble amyloid precursor protein α (sAPPα) levels in lung cancer cell media

Previously, we found that the levels of soluble amyloid precursor protein α (sAPPα) are regulated, in part, by acetylcholinesterase (AChE) in human A549 (p53 wild-type) and H1299 (p53-null) NSCLC cell lines. In this study, we found regulation of sAPPα levels in the media by leptin, a widely recognized obesity-associated adipokine that has recently been shown to play a possible role in cancer signaling. Increased levels of sAPPα, that were accompanied by lower Aβ40/42 levels in the media of A549 and H1299 cells, were detected upon cell incubation with leptin. Conversely, knockdown of leptin or its receptor led to reduced levels of sAPPα and increased levels of Aβ40/42 in the media of A549 and H1299 cells, suggesting that leptin likely shifts APP processing toward the non-amyloidogenic pathway. A549 cell treatment with leptin increased acetylcholine levels and blocked the activities of AChE and p53. Treatment with leptin resulted in increased activation of PKC, ERK1/2, PI3K, and the levels of sAPPα, effects that were reversed by treatment with kinase inhibitors and/or upon addition of AChE to A549 and H1299 cell media. Cell viability increased by treatment of A549 and H1299 cells with leptin and decreased upon co-treatment with AChE and/or inhibitors targeting PKC, ERK1/2, and PI3K. This study is significant as it provides evidence for a likely carcinogenic role of leptin in NSCLC cells via upregulation of sAPPα levels in the media, and highlights the importance of targeting leptin as a potential therapeutic strategy for NSCLC treatment.

Biological screening to identify hits the Therapeutic Targets of Alzheimer's disease and their role in the pathogenesis

Alzheimer's disease (AD) is a major problem in today's societies. More than five million Americans are living with Alzheimer's disease in the United States, with the majority being 65 and older. According to the Alzheimer's Association Report, the number of persons affected by Alzheimer's disease in the United States would rise to fourteen million by 2060. The disease, which is the most prevalent form of dementia, is a progressive and irreversible brain disorder that gradually deteriorates an individual's cognitive function. It advances from preclinical to early- to moderate- to late-stage disease. Early symptoms primarily include cognitive impairment, particularly memory loss. Current Alzheimer's disease treatment can be divided into two categories based on the disease's stage. Galantamine, rivastigmine, and donepezil as acetylcholinesterase inhibitors are suitable for mild to moderate cases to provide transient symptomatic relief among patients. Memantine, an N-methyl D-aspartate (NMDA) antagonist, is used as monotherapy to treat symptoms of moderate to severe Alzheimer's disease. These medications are typically selective molecules that target certain proteins ("one compound-one target" method), and their main goal is to restore physiological acetylcholine levels. Nonetheless, multiple pathways of Alzheimer's disease pathogenesis have been hypothesized to far, and they have been proven to overlap and influence one another.