scholarly journals Preparation of 4-Flexible Amino-2-Arylethenyl-Quinoline Derivatives as Multi-target Agents for the Treatment of Alzheimer’s Disease

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3100 ◽  
Author(s):  
Xiao-Qin Wang ◽  
Chu-Ping Zhao ◽  
Long-Cheng Zhong ◽  
De-Ling Zhu ◽  
De-Hao Mai ◽  
...  

Alzheimer’s disease (AD) is a complex and multifactorial neurodegenerative disorder of aged people. The development of multitarget-directed ligands (MTDLs) to act as multifunctional agents to treat this disease is the mainstream of current research. As a continuation of our previous studies, a series of 4-flexible amino-2-arylethenylquinoline derivatives as multi-target agents was efficiently synthesized and evaluated for the treatment of AD. Among these synthesized derivatives, some compounds exhibited strong self-induced Aβ1–42 aggregation inhibition and antioxidant activity. The structure-activity relationship was summarized, which confirmed that the introduction of a flexible amino group featuring a N,N-dimethylaminoalkylamino moiety at the 4-position increased the Aβ1–42 aggregation inhibition activity, with an inhibition ratio of 95.3% at 20 μM concentration. Compound 6b1, the optimal compound, was able to selectively chelate copper (II), and inhibit Cu2+-induced Aβ aggregation effectively. It also could disassemble the self-induced Aβ1–42 aggregation fibrils with a ratio of 64.3% at 20 μM concentration. Moreover, compound 6b1 showed low toxicity and a good neuroprotective effect against Aβ1–42-induced toxicity in SH-SY5Y cells. Furthermore, the step-down passive avoidance test indicated compound 6b1 significantly reversed scopolamine-induced memory deficit in mice. Taken together, these results suggested that compound 6b1 was a promising multi-target compound worthy of further study for AD.

INDIAN DRUGS ◽  
2019 ◽  
Vol 56 (10) ◽  
pp. 22-25
Author(s):  
M Khambete ◽  
P. Murumkar ◽  
A Kumar ◽  
T. Darreh-Shori ◽  
S. De ◽  
...  

Alzheimer’s disease (AD) is a progressive, neurodegenerative disease which is caused mainly due to accumulation of an aberrant protein known as β-amyloid in the form of senile plaques. However, over the past few years, network biology studies have indicated that classical “one drug-one target” hypothesis may not work in diseases such as AD where the biochemical disease mechanisms are intricately interconnected. therefore, multifunctional molecules which can modulate several targets could be the key towards finding the therapeutics for this debilitating disorder. Keeping this in mind, several pyrazoline containing molecules with promising Aβ aggregation inhibition potential were explored further against key targets involved in AD, such as cholinesterases, oxidative stress and advanced glycation end products (AGe). Some potential multifunctional molecules were identified as a result of this work.


2019 ◽  
Vol 16 (9) ◽  
pp. 772-800 ◽  
Author(s):  
Eva Mezeiova ◽  
Katarina Chalupova ◽  
Eugenie Nepovimova ◽  
Lukas Gorecki ◽  
Lukas Prchal ◽  
...  

: Alzheimer's Disease (AD) is a neurodegenerative disorder with an increasing impact on society. Because currently available therapy has only a short-term effect, a huge number of novel compounds are developed every year exploiting knowledge of the various aspects of AD pathophysiology. To better address the pathological complexity of AD, one of the most extensively pursued strategies by medicinal chemists is based on Multi-target-directed Ligands (MTDLs). Donepezil is one of the currently approved drugs for AD therapy acting as an acetylcholinesterase inhibitor. In this review, we have made an extensive literature survey focusing on donepezil-derived MTDL hybrids primarily targeting on different levels cholinesterases and amyloid beta (Aβ) peptide. The targeting includes direct interaction of the compounds with Aβ, AChE-induced Aβ aggregation, inhibition of BACE-1 enzyme, and modulation of biometal balance thus impeding Aβ assembly.


2020 ◽  
Author(s):  
Hajar Karimi Askarani ◽  
Aida Iraji ◽  
Arezoo Rastegari ◽  
Syed Nasir Abbas Bukhari ◽  
Omidreza Firuzi ◽  
...  

Abstract To discover multifunctional agents for the treatment of Alzheimer's disease (AD), a new series of 1,2,3-triazole-chromenone derivatives were designed and synthesized based on the multi target-directed ligands approach. The in vitro biological activities were evaluated including acetylcholinesterase (AChE), butylcholinesterase (BuChE), and Aβ1−42 aggregation inhibition as well as neuroprotective effects and metal-chelating properties. The results indicated highly selective BuChE inhibitory activity with IC50 values of 21.71 µM for compound 10 h as the most potent compound. Besides, compound 10 h could inhibit self-induced Aβ1−42 aggregation and AChE-induced Aβ aggregation with 32.6% and 29.4% inhibition value, respectively. A Lineweaver–Burk plot and molecular modeling study also showed that compound 10 h targeted both the catalytic active site (CAS) and peripheral anionic site (PAS) of BuChE. It should be noted that compound 10 h was potent as a selective Cu2+ chelator. Thus, the designed scaffold could be considered as multifunctional agents for AD drug discovery developments.


Biomedicines ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 107 ◽  
Author(s):  
Pitchayakarn Takomthong ◽  
Pornthip Waiwut ◽  
Chavi Yenjai ◽  
Bungon Sripanidkulchai ◽  
Prasert Reubroycharoen ◽  
...  

Coumarins, naturally occurring phytochemicals, display a wide spectrum of biological activities by acting on multiple targets. Herein, nine coumarins from the root of Toddalia asiatica were evaluated for activities related to pathogenesis of Alzheimer’s disease (AD). They were examined for acetylcholinesterase (AChE) and AChE- or self-induced amyloid beta (Aβ) aggregation inhibitory activities, as well as neuroprotection against H2O2- and Aβ1–42-induced human neuroblastoma SH-SY5Y cell damage. Moreover, in order to understand the mechanism, the binding interactions between coumarins and their targets: (i) AChE and (ii) Aβ1–42 peptide were investigated in silico. All coumarins exhibited mild to moderate AChE and self-induced Aβ aggregation inhibitory actions. In addition, the coumarins substituted with the long alkyl chain at position 6 or 8 illustrated ability to inhibit AChE-induced Aβ aggregation, resulting from their dual binding site at catalytic anionic site and peripheral active site in AChE. Moreover, the most potent multifunctional coumarin, phellopterin, could attenuate neuronal cell damage induced by H2O2 and Aβ1–42 toxicity. Conclusively, seven out of nine coumarins were identified as multifunctional agents inhibiting the pathogenesis of AD. The structure–activity relationship information obtained might be applied for further optimization of coumarins into a useful drug which may combat AD.


Author(s):  
Hiroshi Mori

Alzheimer’s disease (AD), the most prevalent disease of aged people, is a progressive neurodegenerative disorder with dementia. Amyloid-ß (also known as ß-protein and referred to here as Aß) is a well-established, seminal peptide in AD that is produced from the amyloid precursor protein (APP) by consecutive digestion with the ß secretase of BACE (beta-site amyloid cleaving enzyme) and gamma secretase of the presenilin complex. Abnormal cerebral accumulation of Abeta in the form of insoluble fibrils in senile plaques and cerebral amyloid angiopathy (CAA) is a neuropathological hallmark of AD. In contrast to insoluble fibrillary Aß, a soluble oligomeric complex, ADDL, consists of low-n oligomers of Aß, such as Aß*56. Despite their different names, it is currently proposed that oligomeric Aß is directly involved in synaptic toxicity and cognitive dysfunction in the early stages of AD. This chapter identifies a novel APP mutation (E693delta; referred to as the Osaka mutation) in a pedigree with probable AD, resulting in a variant Aß lacking glutamate at position 22. Based on theoretical predictions and in vitro studies on synthetic mutant Aß peptides, the mutated Aß peptide showed a unique and enhanced oligomerization activity without fibrillization. This was further confirmed by PiB-PET analysis on the proband patient. Collectively, the chapter concludes that the Osaka mutation is the first human evidence for the hypothesis that oligomeric Aß is involved in AD.


2020 ◽  
Vol 21 (16) ◽  
pp. 5858 ◽  
Author(s):  
Md. Sahab Uddin ◽  
Md. Tanvir Kabir ◽  
Md. Sohanur Rahman ◽  
Tapan Behl ◽  
Philippe Jeandet ◽  
...  

Alzheimer’s disease (AD) is the most prevalent neurodegenerative disorder related to age, characterized by the cerebral deposition of fibrils, which are made from the amyloid-β (Aβ), a peptide of 40–42 amino acids. The conversion of Aβ into neurotoxic oligomeric, fibrillar, and protofibrillar assemblies is supposed to be the main pathological event in AD. After Aβ accumulation, the clinical symptoms fall out predominantly due to the deficient brain clearance of the peptide. For several years, researchers have attempted to decline the Aβ monomer, oligomer, and aggregate levels, as well as plaques, employing agents that facilitate the reduction of Aβ and antagonize Aβ aggregation, or raise Aβ clearance from brain. Unluckily, broad clinical trials with mild to moderate AD participants have shown that these approaches were unsuccessful. Several clinical trials are running involving patients whose disease is at an early stage, but the preliminary outcomes are not clinically impressive. Many studies have been conducted against oligomers of Aβ which are the utmost neurotoxic molecular species. Trials with monoclonal antibodies directed against Aβ oligomers have exhibited exciting findings. Nevertheless, Aβ oligomers maintain equivalent states in both monomeric and aggregation forms; so, previously administered drugs that precisely decrease Aβ monomer or Aβ plaques ought to have displayed valuable clinical benefits. In this article, Aβ-based therapeutic strategies are discussed and several promising new ways to fight against AD are appraised.


BMC Chemistry ◽  
2020 ◽  
Vol 14 (1) ◽  
Author(s):  
Hajar Karimi Askarani ◽  
Aida Iraji ◽  
Arezoo Rastegari ◽  
Syed Nasir Abbas Bukhari ◽  
Omidreza Firuzi ◽  
...  

Abstract To discover multifunctional agents for the treatment of Alzheimer's disease (AD), a new series of 1,2,3-triazole-chromenone derivatives were designed and synthesized based on the multi target-directed ligands approach. The in vitro biological activities included acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibition as well as anti-Aβ aggregation, neuroprotective effects, and metal-chelating properties. The results indicated a highly selective BuChE inhibitory activity with an IC50 value of 21.71 μM for compound 10h as the most potent compound. Besides, compound 10h could inhibit self-induced Aβ1–42 aggregation and AChE-induced Aβ aggregation with 32.6% and 29.4% inhibition values, respectively. The Lineweaver–Burk plot and molecular modeling study showed that compound 10h targeted both the catalytic active site (CAS) and peripheral anionic site (PAS) of BuChE. It should be noted that compound 10h was able to chelate biometals. Thus, the designed scaffold could be considered as multifunctional agents in AD drug discovery developments.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Se Jong Oh ◽  
Hae-June Lee ◽  
Ye Ji Jeong ◽  
Kyung Rok Nam ◽  
Kyung Jun Kang ◽  
...  

Abstract Alzheimer’s disease (AD) is a chronic neurodegenerative disorder and the leading cause of dementia, but therapeutic treatment options are limited. Taurine has been reported to have neuroprotective properties against dementia, including AD. The present study aimed to investigate the treatment effect of taurine in AD mice by functional molecular imaging. To elucidate glutamate alterations by taurine, taurine was administered to 5xFAD transgenic mice from 2 months of age, known to apear amyloid deposition. Then, we performed glutamate positron emission tomography (PET) imaging studies for three groups (wild-type, AD, and taurine-treated AD, n = 5 in each group). As a result, brain uptake in the taurine-treated AD group was 31–40% higher than that in the AD group (cortex: 40%, p < 0.05; striatum: 32%, p < 0.01; hippocampus: 36%, p < 0.01; thalamus: 31%, p > 0.05) and 3–14% lower than that in the WT group (cortex: 10%, p > 0.05; striatum: 15%, p > 0.05; hippocampus: 14%, p > 0.05; thalamus: 3%, p > 0.05). However, we did not observe differences in Aβ pathology between the taurine-treated AD and AD groups in immunohistochemistry experiments. Our results reveal that although taurine treatment did not completely recover the glutamate system, it significantly increased metabolic glutamate receptor type 5 brain uptake. Therefore, taurine has therapeutic potential against AD.


2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Yu-Long Lan ◽  
Shuang Zou ◽  
Jian-Jiao Chen ◽  
Jie Zhao ◽  
Shao Li

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder that is characterized by memory loss and cognitive dysfunction. Aquaporin-4 (AQP4), which is primarily expressed in astrocytes, is the major water channel expressed in the central nervous system (CNS). This protein plays an important role in water and ion homeostasis in the normal brain and in various brain pathological conditions. Emerging evidence suggests that AQP4 deficiency impairs learning and memory and that this may be related to the expression of glutamate transporter-1 (GLT-1). Moreover, the colocalization of AQP4 and GLT-1 has long been studied in brain tissue; however, far less is known about the potential influence that the AQP4/GLT-1 complex may have on AD. Research on the functional interaction of AQP4 and GLT-1 has been demonstrated to be of great significance in the study of AD. Here, we review the interaction of AQP4 and GLT-1 in astrocytes, which might play a pivotal role in the regulation of distinct cellular responses that involve neuroprotection against AD. The association of AQP4 and GLT-1 could greatly supplement previous research regarding neuroprotection against AD.


2018 ◽  
Author(s):  
Baruh Polis ◽  
Kolluru D Srikanth ◽  
Vyacheslav Gurevich ◽  
Hava Gil-Henn ◽  
Abraham O. Samson

AbstractAlzheimer’s disease (AD) is a slowly progressive neurodegenerative disorder with an insidious onset. The disease is characterized by cognitive impairment and a distinct pathology with neuritic plaques and neurofibrillary tangles.Growing evidence highlights the role of arginase activity in the manifestation of AD. Upregulation of arginase was shown to contribute to endothelial dysfunction, atherosclerosis, diabetes, and neurodegeneration. Regulation of arginase activity appears to be a promising approach for interfering with the pathogenesis of AD and other metabolic disorders. Therefore, the enzyme represents a novel therapeutic target.Here, we administer an arginase inhibitor L-norvaline to a mouse model of AD. Then, we evaluate the neuroprotective effect of L-norvaline using immunohistochemistry, proteomics, and quantitative polymerase chain reaction assays. Finally, we identify the biological pathways activated by the treatment.Remarkably, we find that L-norvaline treatment reverses the cognitive decline in AD mice. We show the treatment is neuroprotective as indicated by reduced beta-amyloidosis, alleviated microgliosis, and TNFα transcription levels. Moreover, elevated levels of neuroplasticity related protein PSD-95 were detected in the hippocampi of mice treated with L-norvaline. Furthermore, we disclose several biological pathways, which are involved in cell survival and neuroplasticity and are activated by the treatment.Through these modes of action, L-norvaline has the potential to improve the symptoms of AD and even interfere with its pathogenesis. As such, L-norvaline is a promising neuroprotective molecule that might be tailored for the treatment of a range of neurodegenerative disorders.


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