Multifunctional Mono-Triazole Derivatives Inhibit Aβ42 Aggregation and Cu2+-Mediated Aβ42 Aggregation and Protect Against Aβ42-Induced Cytotoxicity

Rapid Discovery of Aβ42 Fibril Disintegrators from Ganoderma lucidum via Ligand Fishing and Their Neuroprotective Effects on Alzheimer's Disease

An amyloid-β (Aβ) fibril is a vital pathogenic factor of Alzheimer's disease (AD). Aβ fibril disintegrators possess great potential to be developed into novel anti-AD agents. Here, a ligand fishing method was employed to rapidly discover Aβ42 fibril disintegrators from Ganoderma lucidum using Aβ42 fibril-immobilized magnetic beads, which led to the isolation of six Aβ42 fibril disintegrators including ganodermanontriol, ganoderic acid DM, ganoderiol F, ganoderol B, ganodermenonol, and ergosterol. Neuroprotective evaluation in vitro exhibited that these Aβ42 fibril disintegrators could significantly mitigate Aβ42-induced neurotoxicity. Among these six disintegrators, ergosterol and ganoderic acid DM with stronger protecting activity were further selected to evaluate their neuroprotective effect on AD in vivo. Results showed that ergosterol and ganoderic acid DM could significantly alleviate Aβ42-induced cognitive dysfunction and hippocampus neuron loss in vivo. Moreover, ergosterol and ganoderic acid DM could significantly inhibit Aβ42-induced neuron apoptosis and Nrf2-mediated neuron oxidative stress in vitro and in vivo.

Review of triazole scaffolds for treatment and diagnosis of Alzheimer's disease

Triazole scaffolds, a series of 5-membered heterocycles, are well known for their high efficacy, low toxicity, and superior pharmacokinetics. Alzheimer's disease (AD) is the first neurodegenerative disorder with complex pathological mechanisms. Triazole, as an aromatic group with three nitrogen atoms, forms polar and non-polar interactions with diverse key residues in the receptor-ligand binding procedure, and has been widely used in the molecular design in the development of anti-AD agents. Moreover, considering the simple synthesis approaches, triazole scaffolds are commonly used to link two pharmacodynamic groups in one chemical molecule, forming multi-target directed ligands (MTDLs). Furthermore, the click reaction between azide- and cyano-modified enzyme and ligand provides feasibility for the new modulator discovery, compound tissue distribution evaluation, enzyme localization, and pharmacological mechanism study, promoting the diagnosis of AD course.

Interaction studies of oxindole-derivatives with β-amyloid peptides inhibiting its aggregation induced by metal ions

Some hydrazones and Schiff bases derived from isatin, an endogenous oxindole formed in the metabolism of tryptophan, were obtained to investigate their effects on in vitro aggregation of β-amyloid peptides (Aβ), macromolecules implicated in Alzheimer's disease. Some hydrazone ligands, prepared by condensation reactions of isatin with hydrazine derivatives, showed a large affinity binding to the synthetic peptides Aβ, particularly to Aβ1-16. Measurements by NMR spectroscopy indicated that those interactions occur mainly at the metal binding site of the peptide, involving His6, His13, and His14 residues, and that hydrazone E-diastereoisomer interacts preferentially with the amyloid peptides. Experimental results were consistent with simulations using a docking approach, where it is demonstrated that the amino acid residues Glu3, His6, His13, and His14 are those that mostly interact with the ligands. Further, these oxindole-derived ligands can efficiently chelate copper(II) and zinc(II) ions, forming moderate stable [ML] 1:1 species. The corresponding formation constants were determined by UV/Vis spectroscopy, by titrations of the ligands with increasing amounts of metal salts, and the obtained log K values were in the range 2.74 to 5.11. Both properties, good affinity for amyloid peptides, and reasonably good capacity of chelating biometal ions, like copper and zinc, can explain the efficient inhibition of Aβ fragments aggregation, as shown by experiments carried out with the oxindole derivatives in the presence of metal ions.

Synthesis and Biological Evaluation of Coumarin Triazoles as Dual Inhibitors of Cholinesterases and β-Secretase

Coumarin is a naturally occurring bioactive pharmacophore with wide occurrence among central nervous system (CNS)-active small molecules. 8-Acetylcoumarin, one of the natural coumarins, is a mild inhibitor of cholinesterases and β-secretase, which are vital targets of Alzheimer's disease. Herein, we synthesized a series of coumarin-triazole hybrids as potential multitargeted drug ligands (MTDLs) with better activity profiles. The coumarin-triazole hybrids occupy the cholinesterase active site gorge from the peripheral to the catalytic anionic site. The most active analogue, 10b, belonging to the 8-acetylcoumarin core, inhibits acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and β-secretase-1 (BACE-1) with IC₅₀ values of 2.57, 3.26, and 10.65 μM, respectively. The hybrid, 10b, crosses the blood-brain barrier via passive diffusion and inhibits the self-aggregation of amyloid-β monomers. The molecular dynamic simulation study reveals the strong interaction of 10b with three enzymes and forming stable complexes. Overall, the results warrant a detailed preclinical investigation of the coumarin-triazole hybrids.

Discovery of novel 5-(2-hydroxyphenyl)-2-phthalide-3(3H)-pyrazolones as balanced multifunctional agents against Alzheimer's disease

Based on previous work, a series of novel 5-(2-hydroxyphenyl)-2-phthalide-3(3H)-pyrazolones derivatives were identified as potential multifunctional therapeutic agents for Alzheimer's disease. Biological evaluation exhibited that these derivatives had great performance against MAO-B, Aβ_1-42 aggregation, oxidative stress and metal ion dyshomeostasis. Among them, 10x was selected as the optimal agent for its excellent MAO-B inhibitory activity (IC₅₀ = 0.41 μM, SI > 24.4), good antioxidant activity (1.16 Trolox equivalent) and anti-Aβ aggregation activity (56.03% and 57.51% for inhibition of self- and Cu²⁺-induced Aβ_1-42 aggregation; 81.91% and 82.40% for disaggregation of self- and Cu²⁺-induced Aβ_1-42 fibrils at 25.0 μM). Besides, 10x also exhibited obvious metal-ion chelating ability, anti-neuroinflammation (NO, TNF-α), neuroprotective activity and BBB permeability. More importantly, in vivo behavioral assessment demonstrated 10x could remarkably improve the memory and cognitive impairment in Aβ_1-42 induced AD mice model. Overall, these test results indicated 10x could serve as a balanced multifunctional anti-AD agent and deserved further research.

An Overview of 1,2,3-triazole-Containing Hybrids and Their Potential Anticholinesterase Activities

Acetylcholine (ACh) neurotransmitter of the cholinergic system in the brain is involved in learning, memory, stress responses, and cognitive functioning. It is hydrolyzed into choline and acetic acid by two key cholinesterase enzymes, viz., acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). A loss or degeneration of cholinergic neurons that leads to a reduction in ACh levels is considered a significant contributing factor in the development of neurodegenerative diseases (NDs) such as Alzheimer's disease (AD). Numerous studies have shown that cholinesterase inhibitors can raise the level of ACh and, therefore, enhance people's quality of life, and, at the very least, it can temporarily lessen the symptoms of NDs. 1,2,3-triazole, a five-membered heterocyclic ring, is a privileged moiety, that is, a central scaffold, and is capable of interacting with a variety of receptors and enzymes to exhibit a broad range of important biological activities. Recently, it has been clubbed with other pharmacophoric fragments/molecules in hope of obtaining potent and selective AChE and/or BuChE inhibitors. The present updated review succinctly summarizes the different synthetic strategies used to synthesize the 1,2,3-triazole moiety. It also highlights the anticholinesterase potential of various 1,2,3-triazole di/trihybrids reported in the past seven years (2015-2022), including a rationale for hybridization and with an emphasis on their structural features for the development and optimization of cholinesterase inhibitors to treat NDs.

Pharmacological exploration of triazole based therapeutics for Alzheimer disease: An overview

Abstract:

Alzheimer`s disease (AD) is an irreversible progressive neurodegenerative disorder which may account for approximately 60-70% cases of dementia worldwide. AD is characterized by impaired behavioural and cognitive functions including memory, language, conception, attentiveness, judgment, and reasoning problems. The two important hallmarks of AD are the appearance of plaques and tangles of amyloid beta (Aβ) and tau proteins, respectively, in the brain based on the etiology of the disease including cholinergic impairment, metal dyshomeostasis, oxidative stress, and degradation of neurotransmitters. Currently, the used medication only provides alleviation of symptoms but not effective in curing the disease that is creating by an urge to develop new molecules to treat AD. Heterocyclic compounds have proven their ability to be developed as drugs for the treatment of various diseases. The five-membered heterocyclic compound triazole has received foremost fascination for the discovery of new drugs due to the possibility of structural variation and proved its significance in various drug categories. Therefore, this review summarizes mainly the recent advancements in the development of novel 1,2,3-triazole and 1,2,4-triazole based molecules in the drug discovery process for targeting various AD targets such as phosphodiesterase 1 (PDE1) Inhibitors, Apoptosis signal-regulating kinase 1 (ASK1) inhibitors, Somatostatin receptor subtype-4 (SSTR4) agonist, many other druggable targets, molecular modelling studies as well as various methodology for the synthesis of triazoles containing molecules such as Click reaction, Pellizzari and Einhorn-Brunner Reaction.

Nanoglycocluster based diagnostic platform for colorimetric detection of bacteria; A comparative study analysing the effect of AuNPs size, linker length, and glycan diversity

Nanoglycoclusters, an upcoming class of functional nanomaterial are known to drive various processes like detection, imaging, targeting proteins, cells, and bacteria. Nanoglycoclusters are a type of nanomaterial functionalized with various glycans. The array of glycan in multiple copies enhances binding affinity with proteins. Selective and sensitive bacteria/lectin interactions using nanomaterials are an emerging area of research. The measurement of different ligand receptor interactions require sophisticated analytical tools that limit the application in biosensor domain. Recently, colorimetric biosensors gained importance in the field of the biosensor for the detection of bacteria/lectins. Herein we have demonstrated that different size of gold nanoparticles (AuNPs) along with various polyethylene glycol (PEG) linkers, functionalized with synthesized monopod and tripod of mannose and galactose that have different bacteria/lectins specificity. The newly synthesized nanoglycoclusters were able to discriminate between different lectins and bacteria. The aggregation of specific nanoglycocluster upon interaction with specific bacteria/lectins revealed that mannose monopod (MM) and mannose tripod (MT) are specific to Escherichia coli and concanavalin A (ConA) lectin, while galactose monopod (GM) and galactose tripod (GT) are specific to Pseudomonas aeruginosa and Peanut agglutinin (PNA) lectin. Further, the binding events depict the affinity of tripod glycans is more with respect to its corresponding monopod glycans. Our findings explored the potential of colorimetric sensing depending upon the size of AuNPs, linker length, specificity, along with glycans density to develop user friendly diagnostic system for the detection of bacteria.

Inhibition of Aβ peptide aggregation by ruthenium(II) polypyridyl complexes through copper chelation

Alzheimer's disease (AD) is known as a complex multifactorial syndrome and both metal chelators and amyloid β peptide (Aβ) inhibitors show promise against AD. Herein, four small hybrid compounds have been designed and synthesized utilizing 8-hydroxyquinoline, pyridine or imidazole as chelators and benzimidazole as the recognition moiety for AD treatment. These conjugates can capture Cu²⁺ from Aβ and become dimers upon Cu²⁺ coordination and show high efficiency for both Cu²⁺ elimination and Aβ assembly inhibition. Besides, these designed complexes can inhibit the production of Aβ-induced reactive oxygen species (ROS), protect mitochondria from damage, and improve the survival rate of neuron cells. Our work provides a new strategy to combine hydrophobic interaction and metal ion chelation to design amyloid inhibitors.

Alizarin and Purpurin from Rubia tinctorum L. Suppress Insulin Fibrillation and Reduce the Amyloid-Induced Cytotoxicity

Alizarin (1,2-dihydroxyanthraquinone) and purpurin (1,2,4-trihydroxyanthraquinone), natural anthraquinone compounds from Rubia tinctorum L., are reported to have diverse biological effects including antibacterial, antitumor, antioxidation, and so on, but the inhibition activity against amyloid aggregation has been rarely reported. In this study, we used insulin as a model protein to explore the anti-amyloid effects of the two compounds. The results showed that alizarin and purpurin inhibited the formation of insulin fibrils in a dose-dependent manner and reduced insulin-induced cytotoxicity. Meanwhile, purpurin had a more significant inhibitory effect on insulin amyloid fibrils compared with alizarin. In addition, computer simulations indicated that the two compounds interacted mainly with the hydrophobic residues of insulin chain B and interfered with the binding of phenylalanine residues. The research indicated that natural anthraquinone compounds had potential effects in preventing protein misfolding diseases and could be further used to design effective antiamyloidosis compounds.

Enhancing the binding of the β-sheet breaker peptide LPFFD to the amyloid-β fibrils by aromatic modifications: A molecular dynamics simulation study

Alzheimer's is a fatal neurodegenerative disease for which there is no cure at present. The disease is characterized by the presence of plaques in the brains of a patient, which are composed mainly of aggregates of the amyloid-β peptide in the form of β-sheet fibrils. Here, we investigated the possibility of exploiting the superior binding ability of aromatic amino acids to a particular model of the amyloid-β fibrils. which is a difficult target for drug design. The β-sheet breaker peptide LPFFD was modified with aromatic amino acids and its binding to these fibrils was studied. We found that the orientation and the electrostatic complementarity of the modified peptide with respect to the fibrils played a crucial role in determining whether its binding was improved by the aromatic amino acids. The modified LPFFD peptides were able to bind to those fibril residues. which are important in the aggregation of amyloid-β peptides and thus can potentially inhibit the further aggregation of the amyloid-beta peptides by blocking their interactions. We found that the tryptophan modified LPFFD peptides had the best binding affinities. In most cases, the aromatic amino acids in the N-terminus of the modified peptides made more contacts with the fibrils than those in the C-terminus. We also found that increasing the aromatic content did not significantly improve the binding of the LPFFD peptide to the fibrils. Our study can serve as a basis for the design of novel peptide-based drugs for Alzheimer's disease in which aromatic interactions play an important role.

Serotonin and Melatonin Show Different Modes of Action on Aβ42 Protofibril Destabilization

Alzheimer's disease (AD) is associated with the aberrant self-assembly of amyloid-β (Aβ) protein into fibrillar deposits. The disaggregation of Aβ fibril is believed as one of the major therapeutic strategies for treating AD. Previous experimental studies reported that serotonin (Ser), one of the indoleamine neurotransmitters, and its derivative melatonin (Mel) are able to disassemble preformed Aβ fibrils. However, the fibril-disruption mechanisms are unclear. As the first step to understand the underlying mechanism, we investigated the interactions of Ser and Mel molecules with the LS-shaped Aβ₄₂ protofibril by performing a total of nine individual 500 ns all-atom molecular dynamics (MD) simulations. The simulations demonstrate that both Ser and Mel molecules disrupt the local β-sheet structure, destroy the salt bridges between K28 side chain and A42 COO^-, and consequently destabilize the global structure of Aβ₄₂ protofibril. The Mel molecule exhibits a greater binding capacity than the Ser molecule. Intriguingly, we find that Ser and Mel molecules destabilize Aβ₄₂ protofibril through different modes of action. Ser preferentially binds with the aromatic residues in the N-terminal region through π-π stacking interactions, while Mel binds not only with the N-terminal aromatic residues but also with the C-terminal hydrophobic residues via π-π and hydrophobic interactions. This work reveals the disruptive mechanisms of Aβ₄₂ protofibril by Ser and Mel molecules and provides useful information for designing drug candidates against AD.

An α-helix mimetic oligopyridylamide, ADH-31, modulates Aβ42 monomer aggregation and destabilizes protofibril structures: insights from molecular dynamics simulations

Alzheimer's disease (AD), an epidemic growing worldwide due to no effective medical aid available in the market, is a neurological disorder. AD is known to be directly associated with the toxicity of amyloid-β (Aβ) aggregates. In search of potent inhibitors of Aβ aggregation, Hamilton and co-workers reported an α-helix mimetic, ADH-31, which acts as a powerful antagonist of Aβ42 aggregation. To identify the key interactions between protein-ligand complexes and to gain insights into the inhibitory mechanism of ADH-31 against Aβ42 aggregation, molecular dynamics (MD) simulations were performed in the present study. The MD simulations highlighted that ADH-31 showed distinct binding capabilities with residues spanning from the N-terminal to the central hydrophobic core (CHC) region of Aβ42 and restricted the conformational transition of the helix-rich structure of Aβ42 into another form of secondary structures (coil/turn/β-sheet). Hydrophobic contacts, hydrogen bonding and π-π interaction contribute to the strong binding between ADH-31 and Aβ42 monomer. The Dictionary of Secondary Structure of Proteins (DSSP) analysis highlighted that the probability of helical content increases from 38.5% to 50.2% and the turn content reduces from 14.7% to 6.2% with almost complete loss of the β-sheet structure (4.5% to 0%) in the Aβ42 monomer + ADH-31 complex. The per-residue binding free energy analysis demonstrated that Arg5, Tyr10, His14, Gln15, Lys16, Val18, Phe19 and Lys28 residues of Aβ42 are responsible for the favourable binding free energy in Aβ42 monomer + ADH-31 complex, which is consistent with the 2D HSQC NMR of the Aβ42 monomer that depicted a change in the chemical shift of residues spanning from Glu11 to Phe20 in the presence of ADH-31. The MD simulations highlighted the prevention of sampling of amyloidogenic β-strand conformations in Aβ42 trimer in the presence of ADH-31 as well as the ability of ADH-31 to destabilize Aβ42 trimer and protofibril structures. The lower binding affinity between Aβ42 trimer chains in the presence of ADH-31 highlights the destabilization of the Aβ42 trimer structure. Overall, MD results highlighted that ADH-31 inhibited Aβ42 aggregation by constraining Aβ peptides into helical conformation and destabilized Aβ42 trimer as well as protofibril structures. The present study provides a theoretical insight into the atomic level details of the inhibitory mechanism of ADH-31 against Aβ42 aggregation as well as protofibril destabilization and could be implemented in the structure-based drug design of potent therapeutic agents for AD.

Attenuation of Oxidative Stress by Cannabinoids and Cannabis Extracts in Differentiated Neuronal Cells

In this proof-of-concept study, the antioxidant activity of phytocannabinoids, namely cannabidiol (CBD) and Δ9- tetrahydrocannabinol (THC), were investigated using an in vitro system of differentiated human neuronal SY-SH5Y cells. The oxidative stress was induced by hydrogen peroxide, as reactive oxygen species (ROS). Alzheimer's disease (AD)-like pathological conditions were mimicked in vitro by treating the differentiated neuronal cells with amyloid-β_1-42 (Aβ_1-42) in the presence of Cu(II). We showed that THC had a high potency to combat oxidative stress in both in vitro models, while CBD did not show a remarkable antioxidant activity. The cannabis extracts also exhibited a significant antioxidant activity, which depended on the ratio of the THC and CBD. However, our results did not suggest any antagonist effect of the CBD on the antioxidant activity of THC. The effect of cannabis extracts on the cell viability of differentiated human neuronal SY-SH5Y cells was also investigated, which emphasized the differences between the bioactivity of cannabis extracts due to their composition. Our preliminary results demonstrated that cannabis extracts and phytocannabinoids have a promising potential as antioxidants, which can be further investigated to develop novel pharmaceuticals targeting oxidative stress therapy.

Impact of Mutations on the Conformational Transition from α-Helix to β-Sheet Structures in Arctic-Type Aβ40: Insights from Molecular Dynamics Simulations

The amyloid-β (Aβ) protein aggregation into toxic oligomers and fibrils has been recognized as a key player in the pathogenesis of Alzheimer's disease. Recent experiments reported that a double alanine mutation (L17A/F19A) in the central hydrophobic core (CHC) region of [G22]Aβ₄₀ (familial Arctic mutation) diminished the self-assembly propensity of [G22]Aβ₄₀. However, the molecular mechanism behind the decreased aggregation tendency of [A17/A19/G22]Aβ₄₀ is not well understood. Herein, we carried out molecular dynamics simulations to elucidate the structure and dynamics of [G22]Aβ₄₀ and [A17/A19/G22]Aβ₄₀. The results for the secondary structure analysis reveal a significantly increased amount of the helical content in the CHC and C-terminal region of [A17/A19/G22]Aβ₄₀ as compared to [G22]Aβ₄₀. The bending free-energy analysis of D23-K28 salt bridge suggests that the double alanine mutation in the CHC region of [G22]Aβ₄₀ has the potential to reduce the fibril formation rate by 0.57 times of [G22]Aβ₄₀. Unlike [G22]Aβ₄₀, [A17/A19/G22]Aβ₄₀ largely sampled helical conformation, as determined by the minimum energy conformations extracted from the free-energy landscape. The present study provided atomic level details into the experimentally observed diminished aggregation tendency of [A17/A19/G22]Aβ₄₀ as compared to [G22]Aβ₄₀.

Multitarget Therapeutic Strategies for Alzheimer's Disease: Review on Emerging Target Combinations

Neurodegenerative diseases represent nowadays one of the major health problems. Despite the efforts made to unveil the mechanism leading to neurodegeneration, it is still not entirely clear what triggers this phenomenon and what allows its progression. Nevertheless, it is accepted that neurodegeneration is a consequence of several detrimental processes, such as protein aggregation, oxidative stress, and neuroinflammation, finally resulting in the loss of neuronal functions. Starting from these evidences, there has been a wide search for novel agents able to address more than a single event at the same time, the so-called multitarget-directed ligands (MTDLs). These compounds originated from the combination of different pharmacophoric elements which endowed them with the ability to interfere with different enzymatic and/or receptor systems, or to exert neuroprotective effects by modulating proteins and metal homeostasis. MTDLs have been the focus of the latest strategies to discover a new treatment for Alzheimer's disease (AD), which is considered the most common form of dementia characterized by neurodegeneration and cognitive dysfunctions. This review is aimed at collecting the latest and most interesting target combinations for the treatment of AD, with a detailed discussion on new agents with favorable in vitro properties and on optimized structures that have already been assessed in vivo in animal models of dementia.

How Does the Mono-Triazole Derivative Modulate Aβ42 Aggregation and Disrupt a Protofibril Structure: Insights from Molecular Dynamics Simulations

Clinical studies have identified that abnormal self-assembly of amyloid-β (Aβ) peptide into toxic fibrillar aggregates is associated with the pathology of Alzheimer's disease (AD). The most acceptable therapeutic approach to stop the progression of AD is to inhibit the formation of β-sheet-rich structures. Recently, we designed and evaluated a series of novel mono-triazole derivatives 4(a-x), where compound 4v was identified as the most potent inhibitor of Aβ₄₂ aggregation and disaggregates preformed Aβ₄₂ fibrils significantly. Moreover, 4v strongly averts the Cu²⁺-induced Aβ₄₂ aggregation and disaggregates the preformed Cu²⁺-induced Aβ₄₂ fibrils, halts the generation of reactive oxygen species, and shows neuroprotective effects in SH-SY5Y cells. However, the underlying molecular mechanism of inhibition of Aβ₄₂ aggregation by 4v and disaggregation of preformed Aβ₄₂ fibrils remains obscure. In this work, molecular dynamics (MD) simulations have been performed to explore the conformational ensemble of the Aβ₄₂ monomer and a pentameric protofibril structure of Aβ₄₂ in the presence of 4v. The MD simulations highlighted that 4v binds preferentially at the central hydrophobic core region of the Aβ₄₂ monomer and chains D and E of the Aβ₄₂ protofibril. The dictionary of secondary structure of proteins analysis indicated that 4v retards the conformational conversion of the helix-rich structure of the Aβ₄₂ monomer into the aggregation-prone β-sheet conformation. The binding free energy calculated by the molecular mechanics Poisson-Boltzmann surface area method revealed an energetically favorable process with ΔG _binding = -44.9 ± 3.3 kcal/mol for the Aβ₄₂ monomer-4v complex. The free energy landscape analysis highlighted that the Aβ₄₂ monomer-4v complex sampled conformations with significantly higher helical contents (35 and 49%) as compared to the Aβ₄₂ monomer alone (17%). Compound 4v displayed hydrogen bonding with Gly37 (chain E) and π-π interactions with Phe19 (chain D) of the Aβ₄₂ protofibril. Further, the per-residue binding free energy analysis also highlighted that Phe19 (chain D) and Gly37 (chain E) of the Aβ₄₂ protofibril showed the maximum contribution in the binding free energy. The decreased binding affinity and residue-residue contacts between chains D and E of the Aβ₄₂ protofibril in the presence of 4v indicate destabilization of the Aβ₄₂ protofibril structure. Overall, the structural information obtained through MD simulations indicated that 4v stabilizes the native helical conformation of the Aβ₄₂ monomer and persuades a destabilization in the protofibril structure of Aβ₄₂. The results of the study will be useful in the rational design of potent inhibitors against amyloid aggregation.

Design, synthesis, biological evaluation and molecular docking study of novel pyridoxine–triazoles as anti-Alzheimer's agents

A series of multi-target natural product-pyridoxine based derivatives were designed, synthesized, characterized and evaluated as anti-Alzheimer agents. In vitro testing revealed the multi-functional properties of compounds such as inhibition of acetylcholinesterase (AChE), antioxidant and metal chelation. Among the series, 5i derivative was found most potent AChE inhibitor, possess antioxidant potential and chelating metal ions. Further binding interaction of 5i with AChE was studied using molecular docking, showed interaction with both PAS and CAS site of AChE. In silico predictions were also performed to predict toxicity and ADME properties of the molecule 5i and found within drug likeness range. Therefore, 5i could be a promising multi-functional compound that can be used for further development of novel drug for Alzheimer disease.

A series of multi-target natural product-pyridoxine based derivatives were designed, synthesized, characterized and evaluated as anti-Alzheimer agents. Out of all the molecules of the series, 5i was found to be best.

Interactions of a multifunctional di-triazole derivative with Alzheimer's Aβ42monomer and Aβ42protofibril: a systematic molecular dynamics study

The molecular dynamics simulations results highlighted that the multi-target-directed ligand6nstabilizes the native α-helix conformation of the Aβ₄₂monomer and induces a sizable destabilization in the Aβ₄₂protofibril structure.