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The Journal of Neuroscience : the... Jul 2020The endogenous neurotransmitter acetylcholine (ACh) is known to affect the excitatory/inhibitory (E/I) balance of primate visual cortex, enhancing feedforward...
The endogenous neurotransmitter acetylcholine (ACh) is known to affect the excitatory/inhibitory (E/I) balance of primate visual cortex, enhancing feedforward thalamocortical gain while suppressing corticocortical synapses. Recent advances in the study of the human visual system suggest that ACh is a likely component underlying interocular interactions. However, our understanding of its precise role in binocular processes is currently lacking. Here we use binocular rivalry as a probe of interocular dynamics to determine ACh's effects, via the acetylcholinesterase inhibitor (AChEI) donepezil, on the binocular visual system. A total of 23 subjects (13 male) completed two crossover experimental sessions where binocular rivalry measurements were obtained before and after taking either donepezil (5 mg) or a placebo (lactose) pill. We report that enhanced cholinergic potentiation attenuates perceptual suppression during binocular rivalry, reducing the overall rate of interocular competition while enhancing the visibility of superimposition mixed percepts. Considering recent evidence that perceptual suppression during binocular rivalry is causally modulated by the inhibitory neurotransmitter GABA, our results suggest that cholinergic activity counteracts the effect of GABA with regards to interocular dynamics and may modulate the inhibitory drive within the visual cortex. Our research demonstrates that the cholinergic system is implicated in modulating binocular interactions in the human visual cortex. Potentiating the transmission of acetylcholine (ACh) via the cholinergic drug donepezil reduces the extent to which the eyes compete for perceptual dominance when presented two separate, incongruent images.
Topics: Acetylcholine; Adult; Cholinergic Agents; Cholinesterase Inhibitors; Cross-Over Studies; Donepezil; Female; Functional Laterality; Humans; Male; Parasympathetic Nervous System; Photic Stimulation; Psychomotor Performance; Vision Disparity; Vision, Binocular; Young Adult; gamma-Aminobutyric Acid
PubMed: 32457075
DOI: 10.1523/JNEUROSCI.2484-19.2020 -
ELife Dec 2023Perceptual decisions about sensory input are influenced by fluctuations in ongoing neural activity, most prominently driven by attention and neuromodulator systems. It...
Perceptual decisions about sensory input are influenced by fluctuations in ongoing neural activity, most prominently driven by attention and neuromodulator systems. It is currently unknown if neuromodulator activity and attention differentially modulate perceptual decision-making and/or whether neuromodulatory systems in fact control attentional processes. To investigate the effects of two distinct neuromodulatory systems and spatial attention on perceptual decisions, we pharmacologically elevated cholinergic (through donepezil) and catecholaminergic (through atomoxetine) levels in humans performing a visuo-spatial attention task, while we measured electroencephalography (EEG). Both attention and catecholaminergic enhancement improved decision-making at the behavioral and algorithmic level, as reflected in increased perceptual sensitivity and the modulation of the drift rate parameter derived from drift diffusion modeling. Univariate analyses of EEG data time-locked to the attentional cue, the target stimulus, and the motor response further revealed that attention and catecholaminergic enhancement both modulated pre-stimulus cortical excitability, cue- and stimulus-evoked sensory activity, as well as parietal evidence accumulation signals. Interestingly, we observed both similar, unique, and interactive effects of attention and catecholaminergic neuromodulation on these behavioral, algorithmic, and neural markers of the decision-making process. Thereby, this study reveals an intricate relationship between attentional and catecholaminergic systems and advances our understanding about how these systems jointly shape various stages of perceptual decision-making.
Topics: Humans; Attention; Electroencephalography; Donepezil; Atomoxetine Hydrochloride; Neurotransmitter Agents; Decision Making
PubMed: 38038722
DOI: 10.7554/eLife.87022 -
Healthcare (Basel, Switzerland) Jul 2023Behavioral and psychological symptoms of dementia are a major factor in the burden of care and medical expenses. Conventional pharmacological treatments do not exert a...
Efficacy and Safety of Woohwangchungsimwon Combined with Donepezil in Behavioral and Psychological Symptoms of Dementia in Patients with Probable Alzheimer's Disease: Study Protocol for a Randomized Controlled Trial.
Behavioral and psychological symptoms of dementia are a major factor in the burden of care and medical expenses. Conventional pharmacological treatments do not exert a distinct effect on the benefits versus the risks. The herbal medicine woohwangchungsimwon is frequently prescribed for neuropsychiatric disorders. An effect of woohwangchungsimwon on behavioral and psychological symptoms of dementia has been previously reported; however, no clinical studies have been conducted. We aim to evaluate the efficacy and safety of woohwangchungsimwon combined with donepezil for alleviating these symptoms in probable Alzheimer's disease. In this randomized, assessor-blinded, parallel-group clinical trial, 74 participants with probable Alzheimer's disease will be divided via block randomization into a woohwangchungsimwon + donepezil combination group (n = 37) or a donepezil single group (n = 37). Participants will include patients under donepezil treatment for at least a month. We will perform the study for 24 weeks. The Neuro-Psychiatric Inventory subscale scores will be the primary outcome. Secondary outcomes will include cognitive function, dementia severity, physical function, quality of life, depression, anxiety, and insomnia. For safety evaluation, we will assess adverse reactions, measure vital signs, and conduct laboratory tests. This is the first trial aiming to confirm the efficacy and safety of woohwangchungsimwon combined with donepezil for alleviating behavioral and psychological symptoms of dementia. Its findings could provide a basis for their co-administration to control these symptoms in probable Alzheimer's disease.
PubMed: 37510478
DOI: 10.3390/healthcare11142036 -
Frontiers in Aging Neuroscience 2023To conduct a meta-analysis of the effectiveness and safety of ginkgo biloba preparations combined with donepezil hydrochloride vs. donepezil for the treatment of...
OBJECTIVE
To conduct a meta-analysis of the effectiveness and safety of ginkgo biloba preparations combined with donepezil hydrochloride vs. donepezil for the treatment of Alzheimer's disease (AD).
METHODS
Three English databases (Cochrane Library, PubMed, EMBASE), and four Chinese databases [the China National Knowledge Infrastructure (CKNI), the Chinese Biomedical Literature database (CBM), the Chongqing VIP database, and WANFANG DATA)] were manually searched for literature published from the respective dates of inception of the databases to December 2022. The randomized controlled trials (RCTs) of ginkgo biloba preparations with donepezil hydrochloride vs. donepezil for the treatment of AD were included. Relevant literature was screened, and the data in the included studies were extracted for quality assessment according to the Risk of bias tool. The RevMan 5.3 software was used for meta-analysis.
RESULTS
A total of 1,642 participants were enrolled in the 18 RCTs. Of these, 842 were in the experimental group (ginkgo biloba preparations combined with donepezil hydrochloride) and 800 were in the control group (donepezil). The overall methodological quality of the included RCTs is poor due to the high risks of blindness and allocation concealment. The meta-analysis results showed statistically significant differences in several outcomes including Risk Ratio (RR) in change for clinical effectiveness rate (1.23, 95% CI 1.13, 1.34, < 0.00001), mean difference (MD) in change for Mini-Mental State Examination score (3.02, 95% CI 2.14, 3.89, < 0.00001), Activity of Daily Living Scale score (-4.56, 95% CI -5.09, -4.03, < 0.00001), Hasegawa Dementia Scale score (2.04, 95% CI 1.74, 2.34, < 0.00001), Montreal Cognitive Assessment score (2.38, 95% CI 0.72, 4.06, = 0.005), between the experimental and control groups. But there is no statistically significant difference in change for adverse reaction (0.91, 95% CI 0.58, 1.42, = 0.69).
CONCLUSION
Ginkgo biloba preparations plus donepezil can improve clinical effectiveness rate and vocabulary memory outcomes. However, more relevant high-quality RCTs are needed in the future to validate these results.
SYSTEMATIC REVIEW REGISTRATION
Identifier CRD42022378970.
PubMed: 36960422
DOI: 10.3389/fnagi.2023.1124710 -
Journal of Clinical Neurology (Seoul,... Jul 2021The rate of donepezil discontinuation and the underlying reasons for discontinuation in Asian patients with Alzheimer's disease (AD) are currently unknown. We aimed to...
BACKGROUND AND PURPOSE
The rate of donepezil discontinuation and the underlying reasons for discontinuation in Asian patients with Alzheimer's disease (AD) are currently unknown. We aimed to determine the treatment discontinuation rates in AD patients who had newly been prescribed donepezil in routine clinical practice in Asia.
METHODS
This 1-year observational study involved 38 institutions in seven Asian countries, and it evaluated 398 participants aged 50-90 years with a diagnosis of probable AD and on newly prescribed donepezil monotherapy. The primary endpoint was the rate of donepezil discontinuation over 1 year. Secondary endpoints included the reason for discontinuation, treatment duration, changes in cognitive function over the 1-year study period, and compliance as assessed using a clinician rating scale (CRS) and visual analog scale (VAS).
RESULTS
Donepezil was discontinued in 83 (20.9%) patients, most commonly due to an adverse event (43.4%). The mean treatment duration was 103.67 days in patients who discontinued. Among patients whose cognitive function was assessed at baseline and 1 year, there were no significant changes in scores on the Mini-Mental State Examination, Montreal Cognitive Assessment, and Trail-Making Test-Black and White scores, whereas the Clinical Dementia Rating score increased significantly (<0.001). Treatment compliance at 1 year was 96.8% (306/316) on the CRS and 92.6±14.1% (mean±standard deviation) on the VAS.
CONCLUSIONS
In patients on newly prescribed donepezil, the primary reason for discontinuation was an adverse event. Cognitive assessments revealed no significant worsening at 1 year, indicating that continuous donepezil treatment contributes to the maintenance of cognitive function.
PubMed: 34184445
DOI: 10.3988/jcn.2021.17.3.376 -
Cureus Jul 2023Background Dementia is an age-related gradual loss of memory that is progressive in nature. Presently, the most common cause of dementia is Alzheimer's disease (AD),...
Background Dementia is an age-related gradual loss of memory that is progressive in nature. Presently, the most common cause of dementia is Alzheimer's disease (AD), which is treated with donepezil, an anticholinesterase. But it only provides short-term symptomatic improvement. Liraglutide, which is an anti-diabetic drug, stimulates the anti-apoptotic pathway of nerve damage, which helps in regenerating nerve cells; so, it may help in dementia cases. Therefore, this study aimed to explore the effect of liraglutide on learning and memory and to compare its effect with donepezil in diazepam-induced amnesic albino rats. Methodology Twenty healthy male Albino rats weighing 150-200 grams were taken and divided into four groups: A, B, C, and D. Group A rats were normal rats, whereas the rats in groups B, C, and D were made amnesic by the intraperitoneal (i.p.) administration of 0.1 mg per kg of diazepam. Immediately after producing amnesia, group B rats received normal saline, group C received liraglutide, and group D received donepezil through the intraperitoneal route as test drugs. Group A rats received only normal saline. The amnesic effect was measured by the escape latency period, which was measured by using a Morris Water Maize (MWM) instrument. Escape latency is the time (in seconds) to locate the platform from the starting point. The amnesic effect is shown by an increase in escape latency and the anti-amnesic effect by a decrease in escape latency. Escape latency was recorded at 0 hr, 1 hr, 2 hr, 3 hr, and 4 hr after test drug administration. Results Group B rats showed an increase in escape latency, which shows the amnesic effect of diazepam. When group C and group D amnesic rats were treated with liraglutide and donepezil, respectively, a one-hour after-treatment increase in escape latency was seen but after two hours, both groups showed a decrease in escape latency, which indicates the anti-amnesic effect of both drugs. When groups C and D were compared, and the post-hoc highly significant difference (HSD) test was used, there was no significant difference between the two drugs, although the liraglutide-treated group (C) showed a lower anti-amnesic effect. However, group C showed a significant effect as compared to group B rats (p-value <0.05), which indicates the anti-amnesic property of liraglutide as compared to normal saline. Conclusion Liraglutide shows an anti-amnesic property. Since it works by a mechanism different from donepezil, it can be used as add-on therapy with donepezil in dementia patients.
PubMed: 37551235
DOI: 10.7759/cureus.41495 -
Drug Design, Development and Therapy 2020The efficacy of acetylcholinesterase inhibitors (AChE-I) might depend on blood concentration. While rivastigmine metabolism is independent of the cytochrome P450 system,...
BACKGROUND
The efficacy of acetylcholinesterase inhibitors (AChE-I) might depend on blood concentration. While rivastigmine metabolism is independent of the cytochrome P450 system, its isoenzymes, especially CYP2D6, metabolize donepezil. polymorphisms can cause altered enzyme activity resulting in lower or higher than expected drug concentrations of donepezil.
OBJECTIVE
We investigated correlations between clinical efficacy and serum concentrations of rivastigmine and donepezil under special consideration of genotype or gene dose-dependent metabolism of donepezil.
METHODS
Serum concentrations of donepezil and rivastigmine were measured by liquid chromatography - tandem mass spectrometry (LC-MS/MS). Real-time quantitative polymerase chain reaction (PCR) and allele-specific PCR were performed to assess genotype and gene dose.
RESULTS
Patients treated with rivastigmine (n=28) or donepezil (n=48) were included in the study. Both gene dose and metabolism type significantly predicted the level of donepezil serum concentration (p=0.019 and p=0.013, respectively). In the rivastigmine group, changes of the word list delayed recall subtest before treatment and under stable medication were significantly associated with rivastigmine serum levels (β=0.465; p=0.018). Drug serum concentrations were outside the recommended range in a substantial percentage of participants, which might have contributed to poor correlations between changes in cognitive measures and drug concentrations. Donepezil serum concentrations significantly depended on gene dose.
CONCLUSION
Testing AChE-I serum concentration should be considered in patients without clinical response to treatment or those with severe side effects. Patients with donepezil drug levels outside the recommended range might additionally profit from genotyping or treatment with an AChE-I independent of CYP metabolism.
Topics: Aged; Aged, 80 and over; Cholinesterase Inhibitors; Chromatography, Liquid; Cytochrome P-450 CYP2D6; Donepezil; Drug Monitoring; Female; Genotype; Humans; Male; Middle Aged; Real-Time Polymerase Chain Reaction; Rivastigmine; Tandem Mass Spectrometry
PubMed: 32848364
DOI: 10.2147/DDDT.S247259 -
Pharmaceutical Biology Dec 2022Alzheimer's disease (AD) is a neurodegenerative disorder that affects millions of people worldwide. Acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) are...
CONTEXT
Alzheimer's disease (AD) is a neurodegenerative disorder that affects millions of people worldwide. Acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) are promising therapeutic targets for AD.
OBJECTIVE
To evaluate the inhibitory effects of aaptamine on two cholinesterases and investigate the therapeutic effect on AD in a zebrafish model.
MATERIALS AND METHODS
Aaptamine was isolated from the sponge Brøndsted (Suberitidae). Enzyme inhibition, kinetic analysis, surface plasmon resonance (SPR) and molecular docking assays were used to determine its inhibitory effect on AChE and BuChE . Zebrafish were divided into six groups: control, model, 8 μM donepezil, 5 , 10 and 20 μM aaptamine. After three days of drug treatment, the behaviour assay was performed.
RESULTS
The IC values of aaptamine towards AChE and BuChE were 16.0 and 4.6 μM. And aaptamine directly inhibited the two cholinesterases in the mixed inhibition type, with values of 6.96 ± 0.04 and 6.35 ± 0.02 μM, with values of 87.6 and 10.7 μM. Besides, aaptamine interacts with the crucial anionic sites of AChE and BuChE. studies indicated that the dyskinesia recovery rates of 5 , 10 and 20 μM aaptamine group were 34.8, 58.8 and 60.0%, respectively, and that of donepezil was 63.7%.
DISCUSSION AND CONCLUSIONS
Aaptamine showed great potential to exert its anti-AD effects by directly inhibiting the activities of AChE and BuChE. Therefore, this study identified a novel medicinal application of aaptamine and provided a new structural scaffold for the development of anti-AD drugs.
Topics: Acetylcholinesterase; Alzheimer Disease; Animals; Butyrylcholinesterase; Cholinesterase Inhibitors; Donepezil; Humans; Kinetics; Molecular Docking Simulation; Naphthyridines; Zebrafish
PubMed: 35968601
DOI: 10.1080/13880209.2022.2102657 -
Frontiers in Pharmacology 2020Donepezil (DNP) is the first-line drug used for Alzheimer's disease (AD). However, the therapeutic response rate of patients to DNP varies from 20 to 60%. The main... (Review)
Review
Donepezil (DNP) is the first-line drug used for Alzheimer's disease (AD). However, the therapeutic response rate of patients to DNP varies from 20 to 60%. The main reason for the large differences in the clinical efficacy of DNP therapy is genetic factors, some of which affect pharmacokinetics (PK), while others affect pharmacodynamics (PD). Thus, much emphasis has been placed on the investigation of an association between PK- and PD-related gene polymorphisms and therapeutic response to DNP, but a consistent view does not yet exist. In this review, we summarize recent findings regarding genetic factors influencing the clinical efficacy of DNP, including substantial differences in individual responses as a consequence of polymorphisms in Cytochrome P450 (CYP) 2D6, CY3A4, CY3A5, APOE, ABCA1, ABCB1, ESR1, BCHE, PON-1, CHRNA7, and CHAT. We also discuss possible strategies for the evaluation of the clinical efficacy of DNP, with a specific focus on possible biomarkers of PK/PD parameters, and provide perspectives and limitations within the field, which will also be beneficial for understanding the multiple mechanisms of DNP therapy in AD.
PubMed: 32636753
DOI: 10.3389/fphar.2020.00934 -
Frontiers in Pharmacology 2020Aging is a natural biological process associated with cognitive decline and neuroendocrine-immune system changes; the neuroendocrine-immune system plays crucial role in...
Comparison of Donepezil, Memantine, Melatonin, and Liuwei Dihuang Decoction on Behavioral and Immune Endocrine Responses of Aged Senescence-Accelerated Mouse Resistant 1 Mice.
Aging is a natural biological process associated with cognitive decline and neuroendocrine-immune system changes; the neuroendocrine-immune system plays crucial role in brain aging and neurodegeneration, and it is essential to discern beneficial attempts to delay the aging progress based on immunological aging. In this study, we have investigated the effects of Traditional Chinese Medicine (TCM)-Liuwei Dihuang decoction (LW)-and donepezil, memantine, and melatonin on cognitive decline in aging mice. The aged SAMR1 mice received oral administration of donepezil (1mg/kg), memantine (10 mg/kg), melatonin (10 mg/kg), and LW (10 g/kg) for 3 months. A shuttle box, Morris water maze, and elevated-zero maze were performed to assess cognitive function, and flowcytometry, Luminex, and radioimmunoassay were performed to measure the lymphocyte subsets, inflammatory factors, and hormones. We observed that survival days of mice was increased with melatonin and LW, the anxiety behavior was significantly improved by memantine, melatonin, and LW treatment, active avoidance responses significantly improved by LW, donepezil, and memantine, the spatial learning ability was significantly improved by donepezil, and LW and melatonin were beneficial to the spatial memory of old mice. For immune function, LW increased CD4 and CD4CD28 cells and reduced TNF-α, IL-1β, and G-CSF in plasma, and it also promoted the secretion of anti-inflammatory factors IL-4, IL-5, and IL-10 by regulating the active of Th2 cells in spleen. Donepezil and memantine exerted protective effects against CD4CD28 cell decrease caused by aging and reduced the pro-inflammatory factors TNF-α, IL-1β, and G-CSF in plasma. Melatonin could reverse CD8CD28 cell imbalances and increased B cells. For endocrine factors, LW increased TSH levels in the pituitary, and melatonin increased the GH level in blood. Our findings indicated that LW improved the cognitive decline in aging mice, and this might be associated with modulation of the active T cells and HPG axis hormones as well as increasing anti-inflammatory factors. Meanwhile, donepezil and memantine have advantages in regulating adaptive immunity, melatonin has advantages in the regulation of B cells and pituitary hormones, and LW exhibits a better effect on neuroendocrine immune function compared with the others from a holistic point of view. LW might be a potential therapeutic strategy for anti-aging-related syndromes, and it can also provide a value on medication guidance about drug combinations or treatment in clinic.
PubMed: 32477103
DOI: 10.3389/fphar.2020.00350