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Journal of Biomolecular Structure &... Jun 2022Donepezil is an acetylcholinesterase inhibitor (AChEI) in use to treat symptomatic patients of mild to moderate Alzheimer's disease (AD). Ferritin is an iron protein...
Donepezil is an acetylcholinesterase inhibitor (AChEI) in use to treat symptomatic patients of mild to moderate Alzheimer's disease (AD). Ferritin is an iron protein associated with storage and sequestration of excess ferrous iron in a way maintaining proper function of cellular processes and plays a key role in AD since steady-state dysregulation of metal ion metabolism is associated with AD pathology. In lieu of therapeutics importance of ferritin and donepezil in AD, this study aims at investigating the binding between these two employing molecular docking and molecular dynamics (MD) simulation. In this study, we performed structure-based docking of donepezil with human Ferritin. Primarily, the top pose based on the binding affinity was selected and then interaction analysis was carried out to find the stable pose. Structural annotations by docking analysis were further accompanied by all-atom MD simulation for 100 ns followed by principal component and free energy landscape analyses to investigate the conformational changes, stability, and interaction mechanism of ferritin with donepezil. MD simulation suggested that the binding of donepezil stabilizes the ferritin structure and leads to fewer conformational changes. This study gives an insight at the atomistic level into the interaction between donepezil and ferritin thereby aiding in understanding the activity and mechanism of protein and drug binding. The study is clinically significant as iron participates in the occurrence of AD.
Topics: Acetylcholinesterase; Alzheimer Disease; Cholinesterase Inhibitors; Donepezil; Ferritins; Humans; Iron; Molecular Docking Simulation; Molecular Dynamics Simulation
PubMed: 33228460
DOI: 10.1080/07391102.2020.1851302 -
European Journal of Medical Research Oct 2022The purpose of this study was to investigate the neuroprotective effect of donepezil against β-amyloid (Aβ)-induced neurotoxicity and the possible mechanism.
PURPOSE
The purpose of this study was to investigate the neuroprotective effect of donepezil against β-amyloid (Aβ)-induced neurotoxicity and the possible mechanism.
METHODS
PC12 cells were conventionally cultured. Serial concentrations of Aβ and donepezil (0, 0.5, 1, 5, 10, 20 and 50 μmol/L) were added to the PC12 cells, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) staining was performed to detect the effects of these treatments on PC 12 viability. The PC 12 cells were pretreated with 1, 5, 10, 20 or 50 μmol/L donepezil two hours before 20 μmol/L Aβ was added to pretreatment groups A, B, C, D and E. Normal control group I and the 20 μmol/L Aβ-treated group were selected. An MTT assay was used to detect PC12 cell viability, and the level of lactate dehydrogenase (LDH) was determined. PC12 cells were pretreated with 10 μmol/L GF109203X (a protein kinase C [PKC] antagonist) 30 min before 10 μmol/L donepezil was added to pretreatment group F, and normal control group II, the 10 μmol/L GF109203X-treated group and the 10 μmol/L donepezil-treated group were chosen. The expression of phosphorylation-PKC (P-PKC) and its major substrate phosphorylated myristoylated alanine-rich protein C kinase substrate (P-MARCKS) was measured by Western blotting. The effects of donepezil on the subcellular distribution of the PKCα and PKCε isoforms were detected by immunofluorescence staining.
RESULTS
Treatment with Aβ (5, 10, 20 or 50 μmol/L) for 24 h significantly (P < 0.05) decreased PC 12 cell viability in a dose-dependent manner. Compared with the PC12 cells in the control group, those in the 20 μmol/L Aβ-treated group exhibited lower viability but higher LDH release. Compared with the 20 μmol/L Aβ-treated group, pretreatment groups B, C, D and E exhibited significantly (P < 0.05) increased cell viability but significantly (P < 0.05) decreased LDH release. Western blotting demonstrated that compared with control, 10 μmol/L donepezil promoted PKC and MARCKS phosphorylation and that the expression of P-PKC and P-MARCKS in pretreatment group F was significantly (P < 0.05) lower than that in the donepezil-treated group. Immunofluorescence staining revealed that the PKCα and PKCε isoforms were located mainly in the cytoplasm of PC12 control cells, whereas donepezil increased the expression of the PKCα and PKCε isoforms in the membrane fraction. The Western blot results showed that donepezil altered the subcellular distribution of the PKCα and PKCε isoforms by decreasing their expression in the cytosolic fraction but increasing their expression in the membrane fraction.
CONCLUSION
Donepezil can antagonize Aβ-induced neurotoxicity in PC 12 cells, and PKC activation may account for the neuroprotective effect of donepezil.
Topics: Humans; Animals; Rats; Neuroprotective Agents; Donepezil; Peptide Fragments; Protein Kinase C-alpha; Apoptosis
PubMed: 36307893
DOI: 10.1186/s40001-022-00862-1 -
Journal of Chromatography. B,... May 2023Accumulated clinical and biomedical evidence suggests that abnormalities in systemic metabolic processes such as fatty acid and amino acid metabolism can affect the...
Accumulated clinical and biomedical evidence suggests that abnormalities in systemic metabolic processes such as fatty acid and amino acid metabolism can affect the brain function and behavior of various central nervous system diseases such as Alzheimer's disease (AD). In this study, metabolic profiling was used to investigate changes in plasma and urine metabolites following stereotactic injection of amyloid β (Aβ) and treatment with donepezil in rats. Aβ causes cognitive impairment, while donepezil treatment successfully improves memory impairment. Donepezil improves Aβ-induced plasma fatty acid and bile acid metabolism disorders, as well as Aβ-induced urine phenylalanine and tryptophan metabolism disorders in rats. More specifically, the plasma fatty acids improved by donepezil include alpha-linolenic acid, stearidonic acid, eicosapentaenoic acid, docosahexaenoic acid, linoleic acid, arachidonic acid, oleic acid, and palmitic acid, among others. Additionally, donepezil significantly restored the downregulation of bile acids such as ursodeoxycholic acid, cholic acid, and glycocholic acid caused by Aβ. As for urine metabolites, phenylacetylglycine, epinephrine, and other phenylalanine metabolites, as well as kynurenic acid, xanthurenic acid, and other tryptophan metabolites, were worsened by Aβ and improved by donepezil. These findings suggest that the cognitive impairment induced by Aβ and the improvement by donepezil are associated with changes in metabolic disorders in rats. This study provides basic data for the effects of Aβ and donepezil on plasma and urine metabolites in Aβ-induced AD rat models.
Topics: Rats; Animals; Alzheimer Disease; Amyloid beta-Peptides; Donepezil; Tryptophan; Fatty Acids; Disease Models, Animal
PubMed: 37263123
DOI: 10.1016/j.jchromb.2023.123766 -
Journal of Forensic and Legal Medicine Jan 2024Donepezil is one of the primary treatments options for patients suffering from Alzheimer's Disease. In a review of more than 2200 postmortem donepezil positive blood... (Review)
Review
Donepezil is one of the primary treatments options for patients suffering from Alzheimer's Disease. In a review of more than 2200 postmortem donepezil positive blood specimens, 76% of concentrations were higher than the proposed therapeutic range. Means and medians were similar between central blood specimens and peripheral specimens, indicating minimal postmortem redistribution. Postmortem concentrations may not reflect those circulating antemortem. Mean and median postmortem blood concentrations were approximately 3-fold higher than those in antemortem blood specimens. Additionally, in cases where antemortem blood was available for testing, large increases in donepezil concentrations were reported between antemortem and postmortem specimens without documented administration by medical personnel. Elevated blood donepezil concentrations have been reported in multiple postmortem cases where cause of death was unrelated. The blood concentrations reported in cases where donepezil did not contribute to death overlapped with those in suspected drug overdose cases where other drugs may have been present. In 4 out of 5 suspected donepezil overdose cases, blood concentrations greater than 1000 ng/mL were reported, whereas less than 1% of all postmortem blood samples reviewed achieved these concentrations. Blood concentrations greater than 1000 ng/mL should be considered contributory when a drug overdose is suspected. Postmortem donepezil concentrations should be interpreted with caution in the context of a comprehensive case history.
Topics: Humans; Donepezil; Postmortem Changes; Autopsy; Drug Overdose
PubMed: 38043240
DOI: 10.1016/j.jflm.2023.102625 -
Expert Opinion on Pharmacotherapy Oct 2018Alzheimer's disease (AD) is the most common neurodegenerative disease worldwide and carries an immense societal burden. Unfortunately, no curative or disease-modifying... (Review)
Review
Alzheimer's disease (AD) is the most common neurodegenerative disease worldwide and carries an immense societal burden. Unfortunately, no curative or disease-modifying treatment has yet been discovered. The currently approved medications are symptomatic. They include two classes: the cholinesterase inhibitors, such as donepezil, and the NMDA receptor antagonist memantine. Most evidence has shown that combining both classes is superior to monotherapy but may complicate the treatment regimen for patients and families. Namzaric®, a fixed dose combination of donepezil and memantine extended-release (ER) (FDC memantine ER/donepezil), was recently approved by the U.S. Food and Drug Administration (FDA) for patients with moderate to severe AD and warrants further consideration as a clinically useful and advantageous pharmacotherapy in AD. Areas covered: This review discusses the pharmacological properties, efficacy, and safety/tolerability data of this FDC memantine ER/donepezil as well as its benefits and disadvantages for patients and families. A literature search using PubMed was conducted using Namzaric, donepezil, memantine, AD, and medication adherence as keywords. Expert opinion: Aside from its cost, FDC memantine ER/donepezil improves adherence to medication and reduces caregiver burden. It allows patients to benefit from combination therapy as the disease progresses, especially in those with dysphagia, poor adherence and limited caregiver support.
Topics: Alzheimer Disease; Antiparkinson Agents; Cholinesterase Inhibitors; Donepezil; Drug Therapy, Combination; Humans; Memantine
PubMed: 30244611
DOI: 10.1080/14656566.2018.1519022 -
CNS Neuroscience & Therapeutics Oct 2018Alzheimer's disease (AD) is a neurodegenerative disorder that affects over 45 million people worldwide. Patients with severe AD require help with daily activities and... (Review)
Review
BACKGROUND
Alzheimer's disease (AD) is a neurodegenerative disorder that affects over 45 million people worldwide. Patients with severe AD require help with daily activities and show severe memory impairment. Currently, donepezil is one of two drugs approved by FDA and Health Canada for the treatment of severe AD (MMSE score <10). It is prescribed as 5 or 10 mg/d and an FDA-approved 23-mg/d dose.
METHOD
This review will discuss risks and benefits of donepezil at these doses in severe AD. Articles were identified using PubMed using the MeSH terms "donepezil" AND "Alzheimer Disease" AND "severe." Three double-blind, placebo-controlled, randomized studies, one post hoc analysis, and one subgroup analysis were selected.
RESULTS
Donepezil was found to benefit patients in cognition and global functioning. The most consistent improvement was in severe impairment battery (SIB) scores. However, more patients treated with high dosage of donepezil discontinued their treatment due to various adverse events (AEs).
CONCLUSION
Clinicians must weigh benefits against adverse events when determining the course of therapy, as recommendations for cholinesterase inhibitors in advanced AD remain unclear and vary with different guidelines.
Topics: Alzheimer Disease; Cholinesterase Inhibitors; Cognition Disorders; Donepezil; Humans; PubMed
PubMed: 30058285
DOI: 10.1111/cns.13035 -
Current Molecular Pharmacology 2022Alzheimer's disease (AD) is one of the common chronic neurological disorders and associated with cognitive dysfunction, depression and progressive dementia. The presence... (Review)
Review
Alzheimer's disease (AD) is one of the common chronic neurological disorders and associated with cognitive dysfunction, depression and progressive dementia. The presence of β-amyloid or senile plaques, hyper-phosphorylated tau proteins, neurofibrillary tangle, oxidative-nitrative stress, mitochondrial dysfunction, endoplasmic reticulum stress, neuroinflammation and derailed neurotransmitter status are the hallmarks of AD. Currently, donepezil, memantine, rivastigmine and galantamine are approved by the FDA for symptomatic management. It is well-known that these approved drugs only exert symptomatic relief and possess poor patient-compliance. Additionally, various published evidence showed the neuroprotective potential of various nutraceuticals via their antioxidant, anti-inflammatory and anti-apoptotic effects in the preclinical and clinical studies. These nutraceuticals possess a significant neuroprotective potential and hence, can be a future pharmacotherapeutic for the management and treatment of AD. However, nutraceuticals suffer from certain major limitations such as poor solubility, low bioavailability, low stability, fast hepatic- metabolism and larger particle size. These pharmacokinetic attributes restrict their entry into the brain via the blood-brain barrier. Therefore, to overcome such issues, various nanoformulations of nutraceuticals have been developed, that allow their effective delivery into the brain owing to reduced particle size, increased lipophilicity, increased bioavailability and avoidance of fast hepatic metabolism. Thus, in this review, we have discussed the etiology of AD, focusing on the pharmacotherapeutics of nutraceuticals with preclinical and clinical evidence, discussed pharmaceutical limitations and regulatory aspects of nutraceuticals to ensure safety and efficacy. We have further explored various nanoformulations of nutraceuticals as a novel approach to overcome the existing pharmaceutical limitations and for effective delivery into the brain.
Topics: Alzheimer Disease; Amyloid beta-Peptides; Dietary Supplements; Donepezil; Galantamine; Humans
PubMed: 33687906
DOI: 10.2174/1874467214666210309115605 -
PloS One 2023Alzheimer's disease is the most common type of dementia that currently affects over 6.5 million people in the U.S. Currently there is no cure and the existing drug...
A causal inference study: The impact of the combined administration of Donepezil and Memantine on decreasing hospital and emergency department visits of Alzheimer's disease patients.
Alzheimer's disease is the most common type of dementia that currently affects over 6.5 million people in the U.S. Currently there is no cure and the existing drug therapies attempt to delay the mental decline and improve cognitive abilities. Two of the most commonly prescribed such drugs are Donepezil and Memantine. We formally tested and confirmed the presence of a beneficial drug-drug interaction of Donepezil and Memantine using a causal inference analysis. We applied doubly robust estimators to one of the largest and high-quality medical databases to estimate the effect of two commonly prescribed Alzheimer's disease (AD) medications, Donepezil and Memantine, on the average number of hospital or emergency department visits per year among patients diagnosed with AD. Our results show that, compared to the absence of medication scenario, the Memantine monotherapy, and the Donepezil monotherapy, the combined use of Donepezil and Memantine treatment significantly reduces the average number of hospital or emergency department visits per year by 0.078 (13.8%), 0.144 (25.5%), and 0.132 days (23.4%), respectively. The assessed decline in the average number of hospital or emergency department visits per year is consequently associated with a substantial reduction in medical costs. As of 2022, according to the Alzheimer's Disease Association, there were over 6.5 million individuals aged 65 and older living with AD in the US alone. If patients who are currently on no drug treatment or using either Donepezil or Memantine alone were switched to the combined used of Donepezil and Memantine therapy, the average number of hospital or emergency department visits could decrease by over 613 thousand visits per year. This, in turn, would lead to a remarkable reduction in medical expenses associated with hospitalization of AD patients in the US, totaling over 940 million dollars per year.
Topics: Humans; Alzheimer Disease; Donepezil; Memantine; Hospitals; Emergency Service, Hospital
PubMed: 37708117
DOI: 10.1371/journal.pone.0291362 -
Food and Chemical Toxicology : An... Jul 2024An impact of donepezil against doxorubicin-induced gut barrier disruption and gut dysbiosis has never been investigated. Twenty-four male Wistar rats were divided into...
An impact of donepezil against doxorubicin-induced gut barrier disruption and gut dysbiosis has never been investigated. Twenty-four male Wistar rats were divided into three groups. Each group was treated with either vehicle as a control, doxorubicin, or doxorubicin-cotreated with donepezil. Heart rate variability was assessed to reflect the impact of doxorubicin and donepezil. Then, animals were euthanized, and the ileum and its contents were collected in each case to investigate the gut barrier and gut microbiota, respectively. The microbiota-derived endotoxin, trimethylamine N-oxide (TMAO), and short-chain fatty acids (SCFAs) in the serum were determined. An increase in the sympathetic tone, endotoxins, and TMAO levels with disruption of the gut barrier and a decrease in SCFAs levels were observed in doxorubicin-treated rats. Gut microbiota of doxorubicin-treated rats was significantly different from that of the control group. Donepezil treatment significantly decreased the sympathetic tone, restored the gut barrier, and reduced endotoxin and TMAO levels in doxorubicin-treated rats. Nonetheless, donepezil administration did not alter the gut microbiota profile and levels of SCFAs in doxorubicin-treated rats. Doxorubicin impaired the autonomic balance and the gut barrier, and induced gut dysbiosis, resulting in gut toxicity. Donepezil partially improved the doxorubicin-induced gut toxicity through balancing the autonomic disturbance.
Topics: Animals; Donepezil; Doxorubicin; Male; Rats, Wistar; Gastrointestinal Microbiome; Rats; Fatty Acids, Volatile; Dysbiosis; Methylamines; Endotoxins
PubMed: 38759714
DOI: 10.1016/j.fct.2024.114741 -
Alzheimer's Research & Therapy Jun 2023Donepezil is an approved therapy for the treatment of Alzheimer's disease (AD). Results across clinical trials have been inconsistent, which may be explained by... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Donepezil is an approved therapy for the treatment of Alzheimer's disease (AD). Results across clinical trials have been inconsistent, which may be explained by design-methodological issues, the pathophysiological heterogeneity of AD, and diversity of included study participants. We investigated whether response to donepezil differs in mild cognitive impaired (MCI) individuals demonstrating different magnetic resonance imaging (MRI) subtypes.
METHODS
From the Hippocampus Study double-blind, randomized clinical trial, we included 173 MCI individuals (donepezil = 83; placebo = 90) with structural MRI data, at baseline and at clinical follow-up assessments (6-12-month). Efficacy outcomes were the annualized percentage change (APC) in hippocampal, ventricular, and total grey matter volumes, as well as in the AD cortical thickness signature. Participants were classified into MRI subtypes as typical AD, limbic-predominant, hippocampal-sparing, or minimal atrophy at baseline. We primarily applied a subtyping approach based on continuous scale of two subtyping dimensions. We also used the conventional categorical subtyping approach for comparison.
RESULTS
Donepezil-treated MCI individuals showed slower atrophy rates compared to the placebo group, but only if they belonged to the minimal atrophy or hippocampal-sparing subtypes. Importantly, only the continuous subtyping approach, but not the conventional categorical approach, captured this differential response.
CONCLUSIONS
Our data suggest that individuals with MCI, with hippocampal-sparing or minimal atrophy subtype, may have improved benefit from donepezil, as compared with MCI individuals with typical or limbic-predominant patterns of atrophy. The newly proposed continuous subtyping approach may have advantages compared to the conventional categorical approach. Future research is warranted to demonstrate the potential of subtype stratification for disease prognosis and response to treatment.
TRIAL REGISTRATION
ClinicalTrial.gov NCT00403520. Submission Date: November 21, 2006.
Topics: Humans; Donepezil; Cognitive Dysfunction; Magnetic Resonance Imaging; Alzheimer Disease; Atrophy
PubMed: 37353809
DOI: 10.1186/s13195-023-01253-2