New Galantamine Derivatives with Inhibitory Effect on Acetylcholinesterase Activity

2021 ◽  
Vol 83 (3) ◽  
pp. 1211-1220 ◽  
Author(s):  
Maria I. Lazarova ◽  
Daniela S. Tsekova ◽  
Lyubka P. Tancheva ◽  
Kiril T. Kirilov ◽  
Diamara N. Uzunova ◽  
...  

Background: Inhibitors of acetylcholinesterase (AChE) are used to treat many disorders, among which are neurodegenerative upsets, like Alzheimer’s disease (AD). One of the limited licensed AChE inhibitors (AChEIs) used as drugs is the natural compound galantamine (Gal). Objective: As Gal is a toxic compound, here we expose data about its four derivatives in hybrid peptide-norgalantamine molecules, which have shown 100 times lower toxicity. Methods: Four newly synthesized galantamine derivatives have been involved in docking analysis made by Molegro Virtual Docker. Biological assessments were performed on ICR male mice. The change in short and long-term memory performance was evaluated by passive avoidance test. AChE activity and levels of main oxidative stress parameters: lipid peroxidation, total glutathione (GSH), enzyme activities of catalase (CAT), superoxide dismutase, and glutathione peroxidase were measured in brain homogenates. Results: Our experimental data revealed that the new hybrid molecules did not impair memory performance in healthy mice. Two of the compounds demonstrated better than Gal AChE inhibitory activity in the brain. None of them changed the level of lipid peroxidation products, one of the compounds increased GSH levels, and all of them increased CAT enzyme activity. Conclusion: The new galantamine-peptide hybrids demonstrated a potential for inhibition of AChE and antioxidant activity and deserve further attention.

2017 ◽  
Vol 6 (06) ◽  
pp. 1640 ◽  
Author(s):  
Navi Ranjan* ◽  
Manorma Kumari

Acetylcholinesterase (AChE), the predominant cholinesterase in the brain, hydrolyzes ACh to choline and acetate, thereby terminating the effect of this neurotransmitter at cholinergic synapses. Therefore, AChE is the target of cholinesterase inhibitors used for addressing the cholinergic deficit in Alzheimer’s disease (AD) patients. Despite decades of research and advances in our understanding of its aetiology and pathogenesis, current pharmacotherapeutic options for AD are still very limited and represent an area of need that is currently unmet. The leading AD therapeutics involves AChE inhibitors, resulting in increased acetylcholine concentrations in the synaptic cleft and enhanced cholinergic transmission. Compounds showing an AChE inhibitory effect are also used for the treatment of senile dementia, myastenia gravis, Parkinson’s disease and ataxia. Taking into account that the inhibition of AChE has been one of the most used strategies for treating AD and that existing drugs are effective only against mild to moderate type of disease while presenting considerable side effects, the search for new sources of effective and selective anti acetylcholinesterase agents with fewer side effects is imperative. Various plants and phytochemical substances have demonstrated AChE inhibitory activity and thus could be beneficial in the treatment of neurodegenerative disorders such as AD.


2017 ◽  
Vol 42 (4) ◽  
Author(s):  
Elif Nur Barut ◽  
Burak Barut ◽  
Seçkin Engin ◽  
Sercan Yıldırım ◽  
Ahmet Yaşar ◽  
...  

AbstractObjective:(Methods:Methanol extracts (ME) and ethanol extracts (EE) ofResults:ME had higher antioxidant activities compared to EE. Both extracts displayed a competitive inhibition of acetylcholinesterase; however, the inhibitory activity of ME was higher than EE. The inhibitory constant (KConclusions:Our results showed that


Author(s):  
Ian Neath ◽  
Jean Saint-Aubin ◽  
Tamra J. Bireta ◽  
Andrew J. Gabel ◽  
Chelsea G. Hudson ◽  
...  

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Amal Thebti ◽  
M. A. K. Sanhoury ◽  
H-I. Ouzari ◽  
T. Barhoumi-slimi

The synthesis of new substituted arylphosphoramidates is performed in two steps through phosphorylation of the corresponding alcohols followed by aminolysis. The formation of the desired phosphoramidates depends on the subsequent addition of the two alcohols with the amine being added at the last step. The products were obtained in 58–95% yields. They were characterized mainly by multinuclear (1H, 13C, 31P, and 19F) NMR and IR spectroscopy. In addition, the antimicrobial and antiacetylcholinesterase activities were evaluated. The results showed acetylcholinesterase activity by some compounds, whilst no significant inhibitory effect against the tested bacterial strains has been recorded.


2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Khairunnuur Fairuz Azman ◽  
Rahimah Zakaria ◽  
Che Badariah Abdul Aziz ◽  
Zahiruddin Othman

Ageing and stress exposure may lead to memory impairment while oxidative stress is thought to be one of the underlying mechanisms involved. This study aimed to investigate the potential protective effects of Tualang honey supplementation on memory performance in aged rats exposed to noise stress. Tualang honey supplementation was given orally, 200 mg/kg body weight for 28 days. Rats in the stress group were subjected to loud noise, 100 dB(A), 4 hours daily for 14 days. All rats were subjected to novel object recognition test for evaluation of memory performance. It was observed that the rats subjected to noise stress exhibited significantly lower memory performance and higher oxidative stress as evident by elevated malondialdehyde and protein carbonyl levels and reduction of antioxidant enzymes activities compared to the nonstressed rats. Tualang honey supplementation was able to improve memory performance, decrease oxidative stress levels, increase brain-derived neurotrophic factor (BDNF) concentration, decrease acetylcholinesterase activity, and enhance neuronal proliferation in the medial prefrontal cortex (mPFC) and hippocampus. In conclusion, Tualang honey protects against memory decline due to stress exposure and/or ageing via enhancement of mPFC and hippocampal morphology possibly secondary to reduction in brain oxidative stress and/or upregulation of BDNF concentration and cholinergic system.


2015 ◽  
Vol 66 (2) ◽  
pp. 121-127 ◽  
Author(s):  
Sofia Grabovska ◽  
Yuriу Salyha

Abstract The aim of this study was to investigate how chronic low-dose chlorpyrifos exposure of female Wistar rats before and during pregnancy affects behavioural parameters in their offspring. Four months before pregnancy, we exposed three groups of rats to chlorpyrifos doses of 5, 10, and 15 mg kg-1 body weight every day for 30 days, whereas one group received a single 30 mg kg-1 dose on gestational day 6. When the offspring of the exposed rats grew up, we studied their anxiety rate, motor activity, and cognitive abilities using the respective behavioural tests: open field test, dark/light box, and the extrapolation escape test. The offspring of rats exposed before pregnancy had significantly higher activity rate than controls, and even showed motor agitation and hyperactivity signs. The offspring of rats exposed to the single dose had difficulties solving the extrapolation escape test and showed poorer short- and long-term memory performance. This confirmed that even pre-pregnancy chlorpyrifos exposure can cause neurobehavioral consequences in offspring. Even though the mechanisms of the observed changes remain unclear and need further investigation, these data seem alarming and may serve as an important argument for revising the terms of safe pesticide use


2019 ◽  
Author(s):  
Hayden Schill ◽  
Jeremy Wolfe ◽  
Timothy F. Brady

Memory capacity depends on prior knowledge, both in working memory and in long-term memory. For example, radiologists have improved long-term memory for medical images compared to novices. Furthermore, people tend to remember abnormal or surprising items best. This is often claimed to arise primarily because such items attract additional attention at encoding. How do expertise and abnormality interact when experts are actively searching for abnormalities; e.g. radiologists looking at mammograms? In the current work, we investigate whether expert radiologists (N=32) show improved memory performance for abnormal images compared to novice participants (N=60). We consider two types of “abnormality.” A mammogram can have a focal abnormality that can be localized or it could simply be the mammogram of a woman known to have cancer (e.g. the image of the breast contralateral to the focal abnormality). Must an image have a focal abnormality for additional attentional processing to be engaged? We found that experts have better memory for mammograms than novice participants and enhanced memory for abnormal images relative to normal images. Overall, radiologists showed no memory benefit for the contralateral-abnormal images and did not discriminate them from normal images, but had enhanced memory for images with focal abnormalities. Our results suggest that focal abnormalities play an important role in enhancing memory of expert observers.


2018 ◽  
Author(s):  
Lea M. Bartsch ◽  
Vanessa M. Loaiza ◽  
Lutz Jäncke ◽  
Klaus Oberauer ◽  
Jarrod A. Lewis-Peacock

AbstractMaintenance of information in working memory (WM) is assumed to rely on refreshing and elaboration, but clear mechanistic descriptions of these cognitive processes are lacking, and it is unclear whether they are simply two labels for the same process. This fMRI study investigated the extent to which refreshing, elaboration, and repeating of items in WM are distinct neural processes with dissociable behavioral outcomes in WM and long-term memory (LTM). Multivariate pattern analyses of fMRI data revealed differentiable neural signatures for these processes, which we also replicated in an independent sample of older adults. In some cases, the degree of neural separation within an individual predicted their memory performance. Elaboration improved LTM, but not WM, and this benefit increased as its neural signature became more distinct from repetition. Refreshing had no impact on LTM, but did improve WM, although the neural discrimination of this process was not predictive of the degree of improvement. These results demonstrate that refreshing and elaboration are separate processes that differently contribute to memory performance.HighlightsRepeated reading, refreshing, and elaboration are differentiable in brain activation patterns in both young and older adults.Elaboration selectively improved long-term memory for young adults, and the size of the benefit was related to the neural separability of elaboration from other processes.Older adults implemented a sub-optimal form of elaboration, and this may be a factor contributing to age-related deficits in long-term memory.Ethics statementThe study was approved by the ethical review board of the canton of Zurich (BASEC-No. 2017-00190) and all subjects gave informed written consent in accordance with the Declaration of Helsinki.Data and code availability statementAll behavioral data and analysis scripts can be assessed on the Open Science Framework (osf.io/p2h8b/). The fMRI data that support the findings of this study are available on request from the corresponding author, LMB. The fMRI data are not publicly available due to restrictions of the Swiss Ethics Committees on research involving humans regarding data containing information that could compromise the privacy of research participants.


2020 ◽  
Vol 16 ◽  
pp. 1-15
Author(s):  
Norwardatun Mohamed Razali

Colours are mentioned many times in the Holy Qur’an. Some are mentioned as colours in general, and some of them in specific; yellow, white, black, red, green and blue. Each colour has its special connotations in the Holy Qur’an and among these colours, yellow and red are considered as warm colours. This study aimed to find the significance of warm colours in the Holy Qur’an and its relationship to human psychology; focusing on memory performance. This research had used an inductive approach in terms of selecting Quranic verses; in which yellow and red colour were mentioned. These verses were then analysed by referring to the books of exegetical considerations in order to know the implications of these colours’ usage, as well as referring to psychology books and scientific articles. The research found that yellow and red colour in the Holy Qur’an mostly indicate attracting attention or pleasing viewers. Some examples included the yellow colour in resemblance to the colour of the cow, attention to decay and destruction such as yellow colour in the withering plants, and attention to resurrection like the red colour resembling scene of the Day of Resurrection. This indication in the Holy Qur’an is consistent with psychologists’ discovery; warm colours such as red and yellow are more effective and attractive in the process of transferring information from external to sensory memory, and thus to short-term and long-term memory.


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