The use of multi-target drugs in the treatment of neurodegenerative diseases

Novel multitarget directed ligands inspired by riluzole: A serendipitous synthesis of substituted benzo[b][1,4]thiazepines potentially useful as neuroprotective agents

Riluzole, the first clinically approved treatment for amyotrophic lateral sclerosis (ALS), represents a successful example of a drug endowed with a multimodal mechanism of action. In recent years, different series of riluzole-based compounds have been reported, including several agents acting as Multi-Target-Directed Ligands (MTLDs) endowed with neuroprotective effects. Aiming at identical twin structures inspired by riluzole (2a-c), a synthetic procedure was planned, but the reactivity of the system took a different path, leading to the serendipitous isolation of benzo[b][1,4]thiazepines 3a-c and expanded intermediates N-cyano-benzo[b][1,4]thiazepines 4a-c, which were fully characterized. The newly obtained structures 3a-c, bearing riluzole key elements, were initially tested in an in vitro ischemia/reperfusion injury protocol, simulating the cerebral stroke. Results identified compound 3b as the most effective in reverting the injury caused by an ischemia-like condition, and its activity was comparable, or even higher than that of riluzole, exhibiting a concentration-dependent neuroprotective effect. Moreover, derivative 3b completely reverted the release of Lactate Dehydrogenase (LDH), lowering the values to those of the control slices. Based on its very promising pharmacological properties, compound 3b was then selected to assess its effects on voltage-dependent Na+ and K+ currents. The results indicated that derivative 3b induced a multifaceted inhibitory effect on voltage-gated currents in SH-SY5Y differentiated neurons, suggesting its possible applications in epilepsy and stroke management, other than ALS. Accordingly, brain penetration was also measured for 3b, as it represents an elegant example of a MTDL and opens the way to further ex-vivo and/or in-vivo characterization.

Designing multitarget ligands for neurodegenerative diseases with improved permeability trough PLGA nanoencapsulation

Multitarget ligands (MTLs) have emerged as an interesting alternative for addressing complex multifactorial pathologies such as neurodegenerative diseases. However, a common challenge associated with these compounds is often their high molecular weight and low solubility, which becomes a hurdle when trying to permeate over the blood-brain barrier (BBB). In this study, we have designed two new MTLs that modulate three pharmacological targets simultaneously (tau, beta-amyloid and TAR DNA-binding protein 43). To enhance their brain penetration, we have formulated organic polymeric nanoparticles using poly(lactic-co-glycolic acid). The characterization of the formulations, evaluation of their permeability through an in vitro BBB model, and assessment of their activity on disease-representative cellular models, such as Alzheimer's disease and amyotrophic lateral sclerosis, have been conducted. The results demonstrate the potential of the new MTLs and their nanoparticle encapsulation for the treatment of neurodegenerative diseases.

Practical Three-Component Regioselective Synthesis of Drug-Like 3-Aryl(or heteroaryl)-5,6-dihydrobenzo[h]cinnolines as Potential Non-Covalent Multi-Targeting Inhibitors To Combat Neurodegenerative Diseases

Neurodegenerative diseases (NDs) are one of the prominent health challenges facing contemporary society, and many efforts have been made to overcome and (or) control it. In this research paper, we described a practical one-pot two-step three-component reaction between 3,4-dihydronaphthalen-1(2H)-one (1), aryl(or heteroaryl)glyoxal monohydrates (2a-h), and hydrazine monohydrate (NH2NH2•H2O) for the regioselective preparation of some 3-aryl(or heteroaryl)-5,6-dihydrobenzo[h]cinnoline derivatives (3a-h). After synthesis and characterization of the mentioned cinnolines (3a-h), the in silico multi-targeting inhibitory properties of these heterocyclic scaffolds have been investigated upon various Homo sapiens-type enzymes, including hMAO-A, hMAO-B, hAChE, hBChE, hBACE-1, hBACE-2, hNQO-1, hNQO-2, hnNOS, hiNOS, hPARP-1, hPARP-2, hLRRK-2(G2019S), hGSK-3β, hp38α MAPK, hJNK-3, hOGA, hNMDA receptor, hnSMase-2, hIDO-1, hCOMT, hLIMK-1, hLIMK-2, hRIPK-1, hUCH-L1, hPARK-7, and hDHODH, which have confirmed their functions and roles in the neurodegenerative diseases (NDs), based on molecular docking studies, and the obtained results were compared with a wide range of approved drugs and well-known (with IC50, EC50, etc.) compounds. In addition, in silico ADMET prediction analysis was performed to examine the prospective drug properties of the synthesized heterocyclic compounds (3a-h). The obtained results from the molecular docking studies and ADMET-related data demonstrated that these series of 3-aryl(or heteroaryl)-5,6-dihydrobenzo[h]cinnolines (3a-h), especially hit ones, can really be turned into the potent core of new drugs for the treatment of neurodegenerative diseases (NDs), and/or due to the having some reactionable locations, they are able to have further organic reactions (such as cross-coupling reactions), and expansion of these compounds (for example, with using other types of aryl(or heteroaryl)glyoxal monohydrates) makes a new avenue for designing novel and efficient drugs for this purpose.

Brain modulation by the gut microbiota: From disease to therapy

BACKGROUND

The gut microbiota (GM) and brain are strongly associated, which significantly affects neuronal development and disorders. GM-derived metabolites modulate neuronal function and influence many cascades in age-related neurodegenerative disorders (NDDs). Because of the dual role of GM in neuroprotection and neurodegeneration, understanding the balance between beneficial and harmful bacteria is crucial for applying this approach to clinical therapies.

AIM OF THE REVIEW

This review briefly discusses the role of the gut-brain relationship in promoting brain and cognitive function. Although a healthy gut environment is helpful for brain function, gut dysbiosis can disrupt the brain's environment and create a vicious cycle of degenerative cascades. The ways in which the GM population can affect brain function and the development of neurodegeneration are also discussed. In the treatment and management of NDDs, the beneficial effects of methods targeting GM populations and their derivatives, including probiotics, prebiotics, and fecal microbial transplantation (FMT) are also highlighted.

KEY SCIENTIFIC CONCEPT OF THE REVIEW

In this review, we aimed to provide a deeper understanding of the mechanisms of the gut microbe-brain relationship and their twin roles in neurodegeneration progression and therapeutic applications. Here, we attempted to highlight the different pathways connecting the brain and gut, together with the role of GM in neuroprotection and neuronal development. Furthermore, potential roles of GM metabolites in the pathogenesis of brain disorders and in strategies for its treatment are also investigated. By analyzing existing in vitro, in vivo and clinical studies, this review attempts to identify new and promising therapeutic strategies for central nervous system (CNS) disorders. As the connection between the gut microbe-brain relationship and responses to NDD treatments is less studied, this review will provide new insights into the global mechanisms of GM modulation in disease progression, and identify potential future perspectives for developing new therapies to treat NDDs.

Networkodynamic approach to perceive the key phytoconstituents of E. officinalis (Amla) as natural BACE1 inhibitors: an in-silico study

Alzheimer's disease (AD) is a deteriorating neural disorder, and currently, available drugs are ineffective in its treatment. Emblica officinalis (Amla) is widely recognised in the Indian medicinal system for ameliorative effects in managing diabetes, hyperlipidaemia and neurological diseases. Thus, we aimed to identify the active phytoconstituents of E. officinalis and their role in inhibiting the potential targets for the possible treatment of AD. The network pharmacology approach, gene ontology, molecular docking and molecular dynamics simulation (MDS) studies were performed. A total of 36 bioactive components in E. officinalis, 95 predicted anti-AD targets, and 3398 AD-related targets were identified from different databases. The network analysis showed that BACE1, ABCB1 and AChE, CA2 are the most potential AD targets. Based on gene ontology and topology analysis results, BACE1 was a significant target related to AD pathways, and quercetin, kaempferol and myricetin showed the highest interaction with target genes. The molecular docking results found that rutin and quercetin displayed better binding affinities -7.5, -5.67 kcal/mol than the BACE1 bound internal ligand. Furthermore, MDS results suggested that quercetin and rutin could be potential inhibitors against BACE-1 protein and may have therapeutic effects in treating AD. Such promising results could be further helpful in new drug discovery against AD.Communicated by Ramaswamy H. Sarma.

Current Pharmacotherapy and Multi-Target Approaches for Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by decreased synaptic transmission and cerebral atrophy with appearance of amyloid plaques and neurofibrillary tangles. Cognitive, functional, and behavioral alterations are commonly associated with the disease. Different pathophysiological pathways of AD have been proposed, some of which interact and influence one another. Current treatment for AD mainly involves the use of therapeutic agents to alleviate the symptoms in AD patients. The conventional single-target treatment approaches do not often cause the desired effect in the disease due to its multifactorial origin. Thus, multi-target strategies have since been undertaken, which aim to simultaneously target multiple targets involved in the development of AD. In this review, we provide an overview of the pathogenesis of AD and the current drug therapies for the disease. Additionally, rationales of the multi-target approaches and examples of multi-target drugs with pharmacological actions against AD are also discussed.

Multi-target action of β-alanine protects cerebellar tissue from ischemic damage

Brain ischemic stroke is among the leading causes of death and long-term disability. New treatments that alleviate brain cell damage until blood supply is restored are urgently required. The emerging focus of anti-stroke strategies has been on blood-brain-barrier permeable drugs that exhibit multiple sites of action. Here, we combine single-cell electrophysiology with live-cell imaging to find that β-Alanine (β-Ala) protects key physiological functions of brain cells that are exposed to acute stroke-mimicking conditions in ex vivo brain preparations. β-Ala exerts its neuroprotective action through several distinct pharmacological mechanisms, none of which alone could reproduce the neuroprotective effect. Since β-Ala crosses the blood-brain barrier and is part of a normal human diet, we suggest that it has a strong potential for acute stroke treatment and facilitation of recovery.

Synthesis, In Silico and Pharmacological Evaluation of New Thiazolidine-4-Carboxylic Acid Derivatives Against Ethanol-Induced Neurodegeneration and Memory Impairment

Introduction

Several studies revealed that alcohol utilization impairs memory in adults; however, the underlying mechanism is still unclear. The production of inflammatory markers and reactive oxygen species (ROS) plays a major role in neurodegeneration, which leads to memory impairment. Therefore, targeting neuroinflammation and oxidative distress could be a useful strategy for abrogating the hallmarks of ethanol-induced neurodegeneration. Moreover, several studies have demonstrated multiple biological activities of thiazolidine derivatives including neuroprotection.

Methods

In the current study, we synthesized ten (10) new thiazolidine-4-carboxylic acid derivatives (P1-P10), characterized their synthetic properties using proton nuclear magnetic resonance (¹H-NMR) and carbon-13 NMR, and further investigated the neuroprotective potential of these compounds in an ethanol-induced neuroinflammation model.

Results

Our results suggested altered levels of antioxidant enzymes associated with an elevated level of tumor necrosis factor-alpha (TNF-α), nuclear factor-κB (p-NF-κB), pyrin domain-containing protein 3 (NLRP3), and cyclooxygenase-2 (COX-2) in ethanol-treated animals. Ethanol treatment also led to memory impairment in rats, as assessed by behavioral tests. To further support our notion, we performed molecular docking studies, and all synthetic compounds exhibited a good binding affinity with a fair bond formation with selected targets (NF-κB, TLR4, NLRP3, and COX-2).

Discussion

Overall, our results revealed that these derivatives may be beneficial in reducing neuroinflammation by acting on different stages of inflammation. Moreover, P8 and P9 treatment attenuated the neuroinflammation, oxidative stress, and memory impairment caused by ethanol.

Effects of Linkers and Substitutions on Multitarget Directed Ligands for Alzheimer’s Diseases: Emerging Paradigms and Strategies

Alzheimer’s disease (AD) is multifactorial, progressive and the most predominant cause of cognitive impairment and dementia worldwide. The current “one-drug, one-target” approach provides only symptomatic relief to the condition but is unable to cure the disease completely. The conventional single-target therapeutic approach might not always induce the desired effect due to the multifactorial nature of AD. Hence, multitarget strategies have been proposed to simultaneously knock out multiple targets involved in the development of AD. Herein, we provide an overview of the various strategies, followed by the multitarget-directed ligand (MTDL) development, rationale designs and efficient examples. Furthermore, the effects of the linkers and substitutional functional groups on MTDLs against various targets of AD and their modes of action are also discussed.

Discovery of novel 6-hydroxybenzothiazole urea derivatives as dual Dyrk1A/α-synuclein aggregation inhibitors with neuroprotective effects

A role of Dyrk1A in the progression of Down syndrome-related Alzheimer's disease (AD) is well supported. However, the involvement of Dyrk1A in the pathogenesis of Parkinson's disease (PD) was much less studied, and it is not clear whether it would be promising to test Dyrk1A inhibitors in relevant PD models. Herein, we modified our previously published 1-(6-hydroxybenzo[d]thiazol-2-yl)-3-phenylurea scaffold of Dyrk1A inhibitors to obtain a new series of analogues with higher selectivity for Dyrk1A on the one hand, but also with a novel, additional activity as inhibitors of α-synuclein (α-syn) aggregation, a major pathogenic hallmark of PD. The phenyl acetamide derivative b27 displayed the highest potency against Dyrk1A with an IC50 of 20 nM and high selectivity over closely related kinases. Furthermore, b27 was shown to successfully target intracellular Dyrk1A and to inhibit SF3B1 phosphorylation in HeLa cells with an IC50 of 690 nM. In addition, two compounds among the Dyrk1A inhibitors, b1 and b20, also suppressed the aggregation of α-synuclein (α-syn) oligomers (with IC50 values of 10.5 μM and 7.8 μM, respectively). Both compounds but not the Dyrk1A reference inhibitor harmine protected SH-SY5Y neuroblastoma cells against α-syn-induced cytotoxicity, with b20 exhibiting a higher neuroprotective effect. Compound b1 and harmine were more efficient in protecting SH-SY5Y cells against 6-hydroxydopamine-induced cell death, an effect that was previously correlated to Dyrk1A inactivation in cells but not yet verified using chemical inhibitors. The presented dual inhibitors exhibited a novel activity profile encouraging for further testing in neurodegenerative disease models.

From Kinase Inhibitors to Multitarget Ligands as Powerful Drug Leads for Alzheimer's Disease using Protein-Templated Synthesis

Multitarget directed ligands (MTDLs) are arising as promising tools to tackle complex diseases. The main goal of this work is to create powerful modulating agents for neurodegenerative disorders. To achieve this aim, we have combined fragments that inhibit key protein kinases involved in the main pathomolecular pathways of Alzheimer's disease (AD) such as tau aggregation, neuroinflammation and decreased neurogenesis, whilst looking for a third action in beta-secretase (BACE1), responsible of β-amyloid production. We obtained well-balanced MTDLs with in vitro activity in three different relevant targets and efficacy in two cellular models of AD. Furthermore, computational studies confirmed how these compounds accommodate adequately into the long and rather narrow BACE1 catalytic site. Finally, we employed in situ click chemistry using BACE1 as protein template as a versatile synthetic tool that allowed us to obtain further MTDLs.

Design, synthesis, and evaluation of 3,7-substituted coumarin derivatives as multifunctional Alzheimer's disease agents

Multitarget directed ligands (MTDLs) are emerging as promising treatment options for Alzheimer's disease (AD). Coumarin derivatives serve as a good starting point for designing MTDLs due to their inherent inhibition of monoamine oxidase (MAO) and cholinesterase enzymes, which are complicit in AD's complex pathophysiology. A preliminary series of 3,7-substituted coumarin derivatives were synthesised and evaluated for enzyme inhibitory activity, cytotoxicity as well as neuroprotective ability. The results indicated that the compounds are weak cholinesterase inhibitors with five compounds demonstrating relatively potent inhibition and selectivity towards MAO-B with IC₅₀ values between 0.014 and 0.498 hx00B5;µM. Significant neuroprotective effects towards MPP⁺-compromised SH-SY5Y neuroblastoma cells were also observed, with no inherent cytotoxicity at 10 µM for all compounds. The overall results demonstrated that substitution of the phenylethyloxy moiety at the 7-position imparted superior general activity to the derivatives, with the propargylamine substitution at the 3-position, in particular, displaying the best MAO-B selectivity and neuroprotection.

Stem Cell-Derived Exosomes: a New Strategy of Neurodegenerative Disease Treatment

Short-term symptomatic treatment and dose-dependent side effects of pharmacological treatment for neurodegenerative diseases have forced the medical community to seek an effective treatment for this serious global health threat. Therapeutic potential of stem cell for treatment of neurodegenerative disorders was identified in 1980 when fetal nerve tissue was used to treat Parkinson's disease (PD). Then, extensive studies have been conducted to develop this treatment strategy for neurological disease therapy. Today, stem cells and their secretion are well-known as a therapeutic environment for the treatment of neurodegenerative diseases. This new paradigm has demonstrated special characteristics related to this treatment, including neuroprotective and neurodegeneration, remyelination, reduction of neural inflammation, and recovery of function after induced injury. However, the exact mechanism of stem cells in repairing nerve damage is not yet clear; exosomes derived from them, an important part of their secretion, are introduced as responsible for an important part of such effects. Numerous studies over the past few decades have evaluated the therapeutic potential of exosomes in the treatment of various neurological diseases. In this review, after recalling the features and therapeutic history, we will discuss the latest stem cell-derived exosome-based therapies for these diseases.

Current Approaches and Tools Used in Drug Development against Parkinson's Disease

Parkinson's disease is a progressive neurodegenerative disorder characterized by the death of nerve cells in the substantia nigra of the brain. The treatment options for this disease are very limited as currently the treatment is mainly symptomatic, and the available drugs are not able to completely stop the progression of the disease but only to slow it down. There is still a need to search for new compounds with the most optimal pharmacological profile that would stop the rapidly progressing disease. An increasing understanding of Parkinson's pathogenesis and the discovery of new molecular targets pave the way to develop new therapeutic agents. The use and selection of appropriate cell and animal models that better reflect pathogenic changes in the brain is a key aspect of the research. In addition, computer-assisted drug design methods are a promising approach to developing effective compounds with potential therapeutic effects. In light of the above, in this review, we present current approaches for developing new drugs for Parkinson's disease.

Design, synthesis and in-vitro evaluation of fluorinated triazoles as multi-target directed ligands for Alzheimer disease

Alzheimer disease is multi-factorial and inflammation plays a major role in the disease progression and severity. Metals and reactive oxygen species (ROS) are the key mediators for inflammatory conditions associated with Alzheimer's. Along multi-factorial nature, major challenge for developing new drug is the ability of the molecule to cross blood brain barrier (BBB). We have designed and synthesized multi-target directed hexafluorocarbinol containing triazoles to inhibit Amyloid β aggregation and simultaneously chelate the excess metals present in the extracellular space and scavenge the ROS thus reduce the inflammatory condition. From the screened compound library, compound 1c found to be potent and safe. It has demonstrated inhibition of Amyloid β aggregation (IC₅₀ of 4.6 μM) through selective binding with Amyloid β at the nucleation site (evidenced from the molecular docking). It also chelate metals (Cu⁺², Zn⁺² and Fe⁺³) and scavenges ROS significantly. Due to the presence of hexafluorocarbinol moiety in the molecule it may assist to permeate BBB and improve the pharmacokinetic properties. The in-vitro results of compound 1c indicate the promiscuity for the development of hexafluorocarbinol containing triazoles amide scaffold as multi-target directed therapy against Alzheimer disease.

Dual-Target Compounds against Type 2 Diabetes Mellitus: Proof of Concept for Sodium Dependent Glucose Transporter (SGLT) and Glycogen Phosphorylase (GP) Inhibitors

A current trend in the quest for new therapies for complex, multifactorial diseases, such as diabetes mellitus (DM), is to find dual or even multi-target inhibitors. In DM, the sodium dependent glucose cotransporter 2 (SGLT2) in the kidneys and the glycogen phosphorylase (GP) in the liver are validated targets. Several (β-D-glucopyranosylaryl)methyl (het)arene type compounds, called gliflozins, are marketed drugs that target SGLT2. For GP, low nanomolar glucose analogue inhibitors exist. The purpose of this study was to identify dual acting compounds which inhibit both SGLTs and GP. To this end, we have extended the structure-activity relationships of SGLT2 and GP inhibitors to scarcely known (C-β-D-glucopyranosylhetaryl)methyl arene type compounds and studied several (C-β-D-glucopyranosylhetaryl)arene type GP inhibitors against SGLT. New compounds, such as 5-arylmethyl-3-(β-D-glucopyranosyl)-1,2,4-oxadiazoles, 5-arylmethyl-2-(β-D-glucopyranosyl)-1,3,4-oxadiazoles, 4-arylmethyl-2-(β-D-glucopyranosyl)pyrimidines and 4(5)-benzyl-2-(β-D-glucopyranosyl)imidazole were prepared by adapting our previous synthetic methods. None of the studied compounds exhibited cytotoxicity and all of them were assayed for their SGLT1 and 2 inhibitory potentials in a SGLT-overexpressing TSA201 cell system. GP inhibition was also determined by known methods. Several newly synthesized (C-β-D-glucopyranosylhetaryl)methyl arene derivatives had low micromolar SGLT2 inhibitory activity; however, none of these compounds inhibited GP. On the other hand, several (C-β-D-glucopyranosylhetaryl)arene type GP inhibitor compounds with low micromolar efficacy against SGLT2 were identified. The best dual inhibitor, 2-(β-D-glucopyranosyl)-4(5)-(2-naphthyl)-imidazole, had a K_i of 31 nM for GP and IC₅₀ of 3.5 μM for SGLT2. This first example of an SGLT-GP dual inhibitor can prospectively be developed into even more efficient dual-target compounds with potential applications in future antidiabetic therapy.

Gauging the role and impact of drug interactions and repurposing in neurodegenerative disorders

Neurodegenerative diseases (ND) are of vast origin which are characterized by gradual progressive loss of neurons in the brain region. ND can be classified according to the clinical symptoms present (e.g. Cognitive decline, hyperkinetic, and hypokinetic movements disorder) or by the pathological protein deposited (e.g., Amyloid, tau, Alpha-synuclein, TDP-43). Alzheimer's disease preceded by Parkinson's is the most prevalent form of ND world-wide. Multiple factors like aging, genetic mutations, environmental factors, gut microbiota, blood-brain barrier microvascular complication, etc. may increase the predisposition towards ND. Genetic mutation is a major contributor in increasing the susceptibility towards ND, the concept of one disease-one gene is obsolete and now multiple genes are considered to be involved in causing one particular disease. Also, the involvement of multiple pathological mechanisms like oxidative stress, neuroinflammation, mitochondrial dysfunction, etc. contributes to the complexity and makes them difficult to be treated by traditional mono-targeted ligands. In this aspect, the Poly-pharmacological drug approach which targets multiple pathological pathways at the same time provides the best way to treat such complex networked CNS diseases. In this review, we have provided an overview of ND and their pathological origin, along with a brief description of various genes associated with multiple diseases like Alzheimer's, Parkinson's, Multiple sclerosis (MS), Amyotrophic Lateral Sclerosis (ALS), Huntington's and a comprehensive detail about the Poly-pharmacology approach (MTDLs and Fixed-dose combinations) along with their merits over the traditional single-targeted drug is provided. This review also provides insights into current repurposing strategies along with its regulatory considerations.

Potential roles of natural products in the targeting of proteinopathic neurodegenerative diseases

Defective proteostasis is associated with the gradual accumulations of misfolded proteins and is a hallmark of many age-associated neurodegenerative diseases. In the aged brain, maintenance of the proteostasis network presents a substantial challenge, and its loss contributes to the onset and progression of neurological diseases associated with cognitive decline due to the generation of toxic protein aggregates, a process termed 'proteinopathy'. Emerging evidence suggests that reversing proteinopathies by boosting proteostasis might provide an effective means of preventing neurodegeneration. From this perspective, phytochemicals may play significant roles as potent modulators of the proteostasis network, as previous reports have suggested they can interact with various network components to modify pathologies and confer neuroprotection. This review focuses on some potent phytochemicals that directly or indirectly modulate the proteostasis network and on their possible molecular targets. In addition, we propose strategies for the natural product-based modulation of proteostasis machinery that target proteinopathies.

7-phenoxytacrine is a dually acting drug with neuroprotective efficacy in vivo

N-methyl-D-aspartaterecepro receptor (NMDARs) are a subclass of glutamate receptors, which play an essential role in excitatory neurotransmission, but their excessive overactivation by glutamate leads to excitotoxicity. NMDARs are hence a valid pharmacological target for the treatment of neurodegenerative disorders; however, novel drugs targeting NMDARs are often associated with specific psychotic side effects and abuse potential. Motivated by currently available treatment against neurodegenerative diseases involving the inhibitors of acetylcholinesterase (AChE) and NMDARs, administered also in combination, we developed a dually-acting compound 7-phenoxytacrine (7-PhO-THA) and evaluated its neuropsychopharmacological and drug-like properties for potential therapeutic use. Indeed, we have confirmed the dual potency of 7-PhO-THA, i.e. potent and balanced inhibition of both AChE and NMDARs. We discovered that it selectively inhibits the GluN1/GluN2B subtype of NMDARs via an ifenprodil-binding site, in addition to its voltage-dependent inhibitory effect at both GluN1/GluN2A and GluN1/GluN2B subtypes of NMDARs. Furthermore, whereas NMDA-induced lesion of the dorsal hippocampus confirmed potent anti-excitotoxic and neuroprotective efficacy, behavioral observations showed also a cholinergic component manifesting mainly in decreased hyperlocomotion. From the point of view of behavioral side effects, 7-PhO-THA managed to avoid these, notably those analogous to symptoms of schizophrenia. Thus, CNS availability and the overall behavioral profile are promising for subsequent investigation of therapeutic use.

Compounds isolated from Euonymus spraguei Hayata induce ossification through multiple pathways

The process of bone metabolism includes catabolism of old or mature bone and anabolism of new bone, carried out by osteoclasts and osteoblasts respectively. Any imbalance in this process results in loss of bone mass or osteoporosis. Drugs available to combat osteoporosis have certain adverse effects and are unable to improve bone formation, hence identifying new agents to fulfil these therapeutic gaps is required. To expand the scope of potential agents that enhance bone formation, we identified Euonymus spraguei Hayata as a plant material that possesses robust osteogenic potential using human osteoblast cells. We isolated three compounds, syringaresinol (1), syringin (2), and (−)-epicatechin (3), from E. spraguei. Results demonstrated that syringin (2), and (−)-epicatechin (3), increased alkaline phosphatase activity significantly up to 131.01% and 130.67%, respectively; they also elevated mineral deposition with respective values of up to 139.39% and 138.33%. In addition, 2 and 3 modulated autophagy and the bone morphogenetic protein (BMP)-2 signaling pathway. Our findings demonstrated that 2 and 3 induced osteogenesis by targeting multiple pathways and therefore can be considered as potent multi-targeted drugs for bone formation against osteoporosis.

The endless frontier? The recent increase of R&D productivity in pharmaceuticals

BACKGROUND

Studies on the early 2000s documented increasing attrition rates and duration of clinical trials, leading to a representation of a "productivity crisis" in pharmaceutical research and development (R&D). In this paper, we produce a new set of analyses for the last decade and report a recent increase of R&D productivity within the industry.

METHODS

We use an extensive data set on the development history of more than 50,000 projects between 1990 and 2017, which we integrate with data on sales, patents, and anagraphical information on each institution involved. We devise an indicator to quantify the novelty of each project, based on its set of mechanisms of action.

RESULTS

First, we investigate how R&D projects are allocated across therapeutic areas and find a polarization towards high uncertainty/high potential reward indications, with a strong focus on oncology. Second, we find that attrition rates have been decreasing at all stages of clinical research in recent years. In parallel, for each phase, we observe a significant reduction of time required to identify projects to be discontinued. Moreover, our analysis shows that more recent successful R&D projects are increasingly based on novel mechanisms of action and target novel indications, which are characterized by relatively small patient populations. Third, we find that the number of R&D projects on advanced therapies is also growing. Finally, we investigate the relative contribution to productivity variations of different types of institutions along the drug development process, with a specific focus on the distinction between the roles of Originators and Developers of R&D projects. We document that in the last decade Originator-Developer collaborations in which biotech companies act as Developers have been growing in importance. Moreover, we show that biotechnology companies have reached levels of productivity in project development that are equivalent to those of large pharmaceutical companies.

CONCLUSIONS

Our study reports on the state of R&D productivity in the bio-pharmaceutical industry, finding several signals of an improving performance, with R&D projects becoming more targeted and novel in terms of indications and mechanisms of action.

A Definition of "Multitargeticity": Identifying Potential Multitarget and Selective Ligands Through a Vector Analysis

The design of multitarget drugs is an essential area of research in Medicinal Chemistry since they have been proposed as potential therapeutics for the management of complex diseases. However, defining a multitarget drug is not an easy task. In this work, we propose a vector analysis for measuring and defining "multitargeticity." We developed terms, such as order and force of a ligand, to finally reach two parameters: multitarget indexes 1 and 2. The combination of these two indexes allows discrimination of multitarget drugs. Several training sets were constructed to test the usefulness of the indexes: an experimental training set, with real affinities, a docking training set, within theoretical values, and an extensive database training set. The indexes proved to be useful, as they were used independently in silico and experimental data, identifying actual multitarget compounds and even selective ligands in most of the training sets. We then applied these indexes to evaluate a virtual library of potential ligands for targets related to multiple sclerosis, identifying 10 compounds that are likely leads for the development of multitarget drugs based on their in silico behavior. With this work, a new milestone is made in the way of defining multitargeticity and in drug design.

Synthesis and biological evaluation of acridine-based histone deacetylase inhibitors as multitarget agents against Alzheimer's disease

Multitarget agents simultaneously trigger molecules in functionally complementary pathways, and are therefore considered to have potential in effectively treating Alzheimer's disease (AD), which has a complex pathogenetic mechanism. In this study, the HDAC inhibitor core is incorporated into the acetylcholine esterase (ACE) inhibitor acridine-derived moiety and resulted in compounds that exhibited higher class IIa HDAC (4, 5, 7, and 9)- and class IIb HDAC6-inhibiting activity when compared to the pan-HDAC inhibitor SAHA in clinical practice. One of these compounds, 11b, displayed greater selectivity toward HDAC6 than other isoform enzymes. In contrast, the activity of compound 6a was selective toward class IIa HDAC and HDAC6. These two compounds exhibited strong activity against Aβ-aggregation as well as significantly disrupted Aβ-oligomer. Additionally, 11b and 6a strongly inhibited AChE. These experimental findings demonstrate that compounds 11b and 6a are HDAC-Aβ-aggregation-AChE inhibitors. Notably, they can enhance neurite outgrowth, but with no significant neurotoxicity. Further biological evaluation revealed the various cellular effects of multitarget compounds 11b and 6a, which have the potential to treat AD.

Pharmacological intervention of histone deacetylase enzymes in the neurodegenerative disorders

Reversal of aging symptoms and related disorders are the challenging task where epigenetic is a crucial player that includes DNA methylation, histone modification; chromatin remodeling and regulation that are linked to the progression of various neurodegenerative disorders (NDDs). Overexpression of various histone deacetylase (HDACs) can activate Glycogen synthase kinase 3 which promotes the hyperphosphorylation of tau and inhibits its degradation. While HDAC is important for maintaining the neuronal morphology and brain homeostasis, at the same time, these enzymes are promoting neurodegeneration, if it is deregulated. Different experimental models have also confirmed the neuroprotective effects caused by HDAC enzymes through the regulation of neuronal apoptosis, inflammatory response, DNA damage, cell cycle regulation, and metabolic dysfunction. Apart from transcriptional regulation, protein-protein interaction, histone post-translational modifications, deacetylation mechanism of non-histone protein and direct association with disease proteins have been linked to neuronal imbalance. Histone deacetylases inhibitors (HDACi) can be able to alter gene expression and shown its efficacy on experimental models, and in clinical trials for NDD's and found to be a very promising therapeutic agent with certain limitation, for instance, non-specific target effect, isoform-selectivity, specificity, and limited number of predicted biomarkers. Herein, we discussed (i) the catalytic mechanism of the deacetylation process of various HDAC's in in vivo and in vitro experimental models, (ii) how HDACs are participating in neuroprotection as well as in neurodegeneration, (iii) a comprehensive role of HDACi in maintaining neuronal homeostasis and (iv) therapeutic role of biomolecules to modulate HDACs.

Dreaming of a New World Where Alzheimer's Is a Treatable Disorder

Alzheimer’s disease (AD) is the most common form of dementia. It’s a chronic and untreatable neurodegenerative disease with irreversible progression and has important social and economic implications in terms of direct medical and social care costs. Despite prolonged and expensive efforts employed by the scientific community over the last few decades, no effective treatments are still available for patients, and the development of disease-modifying drugs is now a really urgent need. The recent failure of clinical trials based on the immunotherapeutic approach against amyloid-β(Aβ) protein questioned the validity of the “amyloid cascade hypothesis” as the molecular machinery causing the disease. Indeed, most attempts to design effective treatments for AD have been based until now on molecular targets suggested to be implicated in AD pathogenesis by the amyloid cascade hypothesis. However, mounting evidence from scientific literature supports the view of AD as a multifactorial disease that results from the concomitant action of multiple molecular players. This view, together with the lack of success of the disease-modifying single-target approaches, strongly suggests that AD drug design needs to be shifted towards multi-targeted compounds or drug combinations acting synergistically on the main core features of disease pathogenesis. The discovery of drug candidates targeting multiple factors involved in AD would greatly improve drug development. So, it is reasonable that upcoming strategies for the design of preventive and/or therapeutic agents for AD point to a multi-pronged approach including more than one druggable target to definitely defeat the disease.

Elucidating Critical Proteinopathic Mechanisms and Potential Drug Targets in Neurodegeneration

Neurodegeneration entails progressive loss of neuronal structure as well as function leading to cognitive failure, apathy, anxiety, irregular body movements, mood swing and ageing. Proteomic dysregulation is considered the key factor for neurodegeneration. Mechanisms involving deregulated processing of proteins such as amyloid beta (Aβ) oligomerization; tau hyperphosphorylation, prion misfolding; α-synuclein accumulation/lewy body formation, chaperone deregulation, acetylcholine depletion, adenosine 2A (A2A) receptor hyperactivation, secretase deregulation, leucine-rich repeat kinase 2 (LRRK2) mutation and mitochondrial proteinopathies have deeper implications in neurodegenerative disorders. Better understanding of such pathological mechanisms is pivotal for exploring crucial drug targets. Herein, we provide a comprehensive outlook about the diverse proteomic irregularities in Alzheimer's, Parkinson's and Creutzfeldt Jakob disease (CJD). We explicate the role of key neuroproteomic drug targets notably Aβ, tau, alpha synuclein, prions, secretases, acetylcholinesterase (AchE), LRRK2, molecular chaperones, A2A receptors, muscarinic acetylcholine receptors (mAchR), N-methyl-D-aspartate receptor (NMDAR), glial cell line-derived neurotrophic factor (GDNF) family ligands (GFLs) and mitochondrial/oxidative stress-related proteins for combating neurodegeneration and associated cognitive and motor impairment. Cross talk between amyloidopathy, synucleinopathy, tauopathy and several other proteinopathies pinpoints the need to develop safe therapeutics with ability to strike multiple targets in the aetiology of the neurodegenerative disorders. Therapeutics like microtubule stabilisers, chaperones, kinase inhibitors, anti-aggregation agents and antibodies could serve promising regimens for treating neurodegeneration. However, drugs should be target specific, safe and able to penetrate blood-brain barrier.

Emerging therapeutic potentials of dual-acting MAO and AChE inhibitors in Alzheimer's and Parkinson's diseases

No drug has been approved to prevent neuronal cell loss in patients suffering from Parkinson's disease (PD) or Alzheimer's disease (AD); despite increased comprehension of the underlying molecular causes, therapies target cognitive functional improvement and motor fluctuation control. Drug design strategies that adopt the "one protein, one target" philosophy fail to address the multifactorial aetiologies of neurodegenerative disorders such as AD and PD optimally. On the contrary, restoring neurotransmitter levels by combined combinatorial inhibition of cholinesterases, monoamine oxidases, and adenosine A_2A A receptors, in conjunction with strategies to counter oxidative stress and beta-amyloid plaque accumulation, would constitute a therapeutically robust, multitarget approach. This extensive review delineates the therapeutic advantages of combining dual-acting molecules that inhibit monoamine oxidases and cholinesterases and/or adenosine A_2A A receptors, and describes the structure-activity relationships of compound classes that include, but are not limited to, alkaloids, coumarins, chalcones, donepezil-propargylamine conjugates, homoisoflavonoids, resveratrol analogs, hydrazones, and pyrazolines. In the wake of recent advances in network biology, in silico approaches, and omics, this review emphasizes the need to consider conceptually informed research strategies for drug discovery, in the context of the mounting burden posed by chronic neurodegenerative diseases with complex aetiologies and pathophysiologies involving multiple signalling pathways and numerous drug targets.

Allosteric Modulators of Potential Targets Related to Alzheimer's Disease: a Review

Among neurodegenerative disorders, Alzheimer's disease (AD) is the most common type of dementia, and there is an urgent need to discover new and efficacious forms of treatment for it. Pathological patterns of AD include cholinergic dysfunction, increased β-amyloid (Aβ) peptide concentration, the appearance of neurofibrillary tangles, among others, all of which are strongly associated with specific biological targets. Interactions observed between these targets and potential drug candidates in AD most often occur by competitive mechanisms driven by orthosteric ligands that sometimes result in the production of side effects. In this context, the allosteric mechanism represents a key strategy; this can be regarded as the selective modulation of such targets by allosteric modulators in an advantageous manner, as this may decrease the likelihood of side effects. The purpose of this review is to present an overview of compounds that act as allosteric modulators of the main biological targets related to AD.

Molecular Targets of Bis (7)-Cognitin and Its Relevance in Neurological Disorders: A Systematic Review

Background: The exact mechanisms involved in the pathogenesis of neurodegenerative conditions are not fully known. The design of drugs that act on multiple targets represents a promising approach that should be explored for more effective clinical options for neurodegenerative disorders. B7C is s synthetic drug that has been studied for over 20 years and represents a promising multi-target drug for the treatment of neurodegenerative disorders, such as AD.

Aims: The present systematic review, thus, aims at examining existing studies on the effect of B7C on different molecular targets and at discussing the relevance of B7C in neurological disorders.

Methods: A list of predefined search terms was used to retrieve relevant articles from the databases of Embase, Pubmed, Scopus, and Web of Science. The selection of articles was done by two independent authors, who were considering articles concerned primarily with the evaluation of the effect of B7C on neurological disorders. Only full-text articles written in English were included; whereas, systematic reviews, meta-analyses, book chapters, conference subtracts, and computational studies were excluded.

Results: A total of 2,266 articles were retrieved out of which 41 articles were included in the present systematic review. The effect of B7C on molecular targets, including AChE, BChE, BACE-1, NMDA receptor, GABA receptor, NOS, and Kv4.2 potassium channels was evaluated. Moreover, the studies that were included assessed the effect of B7C on biological processes, such as apoptosis, neuritogenesis, and amyloid beta aggregation. The animal studies examined in the review focused on the effect of B7C on cognition and memory.

Conclusions: The beneficial effects observed on different molecular targets and biological processes relevant to neurological conditions confirm that B7C is a promising multi-target drug with the potential to treat neurological disorders.

Rational Design of Multitarget-Directed Ligands: Strategies and Emerging Paradigms

Due to the complexity of multifactorial diseases, single-target drugs do not always exhibit satisfactory efficacy. Recently, increasing evidence indicates that simultaneous modulation of multiple targets may improve both therapeutic safety and efficacy, compared with single-target drugs. However, few multitarget drugs are on market or in clinical trials, despite the best efforts of medicinal chemists. This article discusses the systematic establishment of target combination, lead generation, and optimization of multitarget-directed ligands (MTDLs). Moreover, we analyze some MTDLs research cases for several complex diseases in recent years and the physicochemical properties of 117 clinical multitarget drugs, with the aim to reveal the trends and insights of the potential use of MTDLs.

The current status of pharmacotherapy for the treatment of Parkinson's disease: transition from single-target to multitarget therapy

Parkinson's disease (PD) is a neurodegenerative disorder characterized by degeneration of dopaminergic neurons. Motor features such as tremor, rigidity, bradykinesia and postural instability are common traits of PD. Current treatment options provide symptomatic relief to the condition but are unable to reverse disease progression. The conventional single-target therapeutic approach might not always induce the desired effect owing to the multifactorial nature of PD. Hence, multitarget strategies have been proposed to simultaneously target multiple proteins involved in the development of PD. Herein, we provide an overview of the pathogenesis of PD and the current pharmacotherapies. Furthermore, rationales and examples of multitarget approaches that have been tested in preclinical trials for the treatment of PD are also discussed.

4-(3-Nitrophenyl)thiazol-2-ylhydrazone derivatives as antioxidants and selective hMAO-B inhibitors: synthesis, biological activity and computational analysis

A new series of 4-(3-nitrophenyl)thiazol-2-ylhydrazone derivatives were designed, synthesised, and evaluated to assess their inhibitory effect on the human monoamine oxidase (hMAO) A and B isoforms. Different (un)substituted (hetero)aromatic substituents were linked to N1 of the hydrazone in order to establish robust structure–activity relationships. The results of the biological testing demonstrated that the presence of the hydrazothiazole nucleus bearing at C4 a phenyl ring functionalised at the meta position with a nitro group represents an important pharmacophoric feature to obtain selective and reversible human MAO-B inhibition for the treatment of neurodegenerative disorders. In addition, the most potent and selective MAO-B inhibitors were evaluated in silico as potential cholinesterase (AChE/BuChE) inhibitors and in vitro for antioxidant activities. The results obtained from molecular modelling studies provided insight into the multiple interactions and structural requirements for the reported MAO inhibitory properties.

Protective effects of polydatin in free and nanocapsulated form on changes caused by lipopolysaccharide in hippocampal organotypic cultures

BACKGROUND

Polydatin (PD) is a compound, originally isolated from the root and rhizome of the Chinese herb Polygonum cuspidatum. To date, various biological properties of this compound, such as analgesic, anti-pyretic or diuretic effects, have been shown. Recently, anti-oxidant and anti-inflammatory properties have been widely postulated, yet PD instability and low bioavailability limit its beneficial actions. Therefore, it has been suggested that an encapsulation process may be a promising strategy for overcoming these limitations and increasing the therapeutic efficacy of PD.

METHODS

We examined the effects of PD in two forms, including free and in PD-loaded polymeric nanocapsules, on lipopolysaccharide (LPS)-induced changes in hippocampal organotypic cultures.

RESULTS

Our results indicated that free and encapsulated PD diminished cell death processes and attenuated the secretion of pro-inflammatory cytokines induced by LPS administration. Additionally, PD in both forms strongly inhibited the production of nitric oxide and down-regulated the level of iNOS enzyme in LPS-stimulated hippocampal cultures.

CONCLUSION

Taken together, our study showed that PD exerts anti-inflammatory and anti-oxidant properties in LPS-treated hippocampal organotypic cultures. Furthermore, we show that the encapsulation procedure preserved the features of the free form of this compound, and therefore, the polymeric nanocapsules containing PD may be used as a novel and promising delivery system in therapeutic strategies.

Optogenetic control of iPS cell-derived neurons in 2D and 3D culture systems using channelrhodopsin-2 expression driven by the synapsin-1 and calcium-calmodulin kinase II promoters

Development of an optogenetically controllable human neural network model in three-dimensional (3D) cultures can provide an investigative system that is more physiologically relevant and better able to mimic aspects of human brain function. Light-sensitive neurons were generated by transducing channelrhodopsin-2 (ChR2) into human induced pluripotent stem cell (hiPSC) derived neural progenitor cells (Axol) using lentiviruses and cell-type specific promoters. A mixed population of human iPSC-derived cortical neurons, astrocytes and progenitor cells were obtained (Axol-ChR2) upon neural differentiation. Pan-neuronal promoter synapsin-1 (SYN1) and excitatory neuron-specific promoter calcium-calmodulin kinase II (CaMKII) were used to drive reporter gene expression in order to assess the differentiation status of the targeted cells. Expression of ChR2 and characterisation of subpopulations in differentiated Axol-ChR2 cells were evaluated using flow cytometry and immunofluorescent staining. These cells were transferred from 2D culture to 3D alginate hydrogel functionalised with arginine-glycine-aspartate (RGD) and small molecules (Y-27632). Improved RGD-alginate hydrogel was physically characterised and assessed for cell viability to serve as a generic 3D culture system for human pluripotent stem cells (hPSCs) and neuronal cells. Prior to cell encapsulation, neural network activities of Axol-ChR2 cells and primary neurons were investigated using calcium imaging. Results demonstrate that functional activities were successfully achieved through expression of ChR2- by both the CaMKII and SYN1 promoters. The RGD-alginate hydrogel system supports the growth of differentiated Axol-ChR2 cells whilst allowing detection of ChR2 expression upon light stimulation. This allows precise and non-invasive control of human neural networks in 3D.

GM604 regulates developmental neurogenesis pathways and the expression of genes associated with amyotrophic lateral sclerosis

Background

Amyotrophic lateral sclerosis (ALS) is currently an incurable disease without highly effective pharmacological treatments. The peptide drug GM604 (GM6 or Alirinetide) was developed as a candidate ALS therapy, which has demonstrated safety and good drug-like properties with a favorable pharmacokinetic profile. GM6 is hypothesized to bolster neuron survival through the multi-target regulation of developmental pathways, but mechanisms of action are not fully understood.

Methods

This study used RNA-seq to evaluate transcriptome responses in SH-SY5Y neuroblastoma cells following GM6 treatment (6, 24 and 48 h).

Results

We identified 2867 protein-coding genes with expression significantly altered by GM6 (FDR < 0.10). Early (6 h) responses included up-regulation of Notch and hedgehog signaling components, with increased expression of developmental genes mediating neurogenesis and axon growth. Prolonged GM6 treatment (24 and 48 h) altered the expression of genes contributing to cell adhesion and the extracellular matrix. GM6 further down-regulated the expression of genes associated with mitochondria, inflammatory responses, mRNA processing and chromatin organization. GM6-increased genes were located near GC-rich motifs interacting with C2H2 zinc finger transcription factors, whereas GM6-decreased genes were located near AT-rich motifs associated with helix-turn-helix homeodomain factors. Such motifs interacted with a diverse network of transcription factors encoded by GM6-regulated genes (STAT3, HOXD11, HES7, GLI1). We identified 77 ALS-associated genes with expression significantly altered by GM6 treatment (FDR < 0.10), which were known to function in neurogenesis, axon guidance and the intrinsic apoptosis pathway.

Conclusions

Our findings support the hypothesis that GM6 acts through developmental-stage pathways to influence neuron survival. Gene expression responses were consistent with neurotrophic effects, ECM modulation, and activation of the Notch and hedgehog neurodevelopmental pathways. This multifaceted mechanism of action is unique among existing ALS drug candidates and may be applicable to multiple neurodegenerative diseases.

Electronic supplementary material

The online version of this article (10.1186/s40035-018-0135-7) contains supplementary material, which is available to authorized users.

Current Screening Methodologies in Drug Discovery for Selected Human Diseases

The increase of many deadly diseases like infections by multidrug-resistant bacteria implies re-inventing the wheel on drug discovery. A better comprehension of the metabolisms and regulation of diseases, the increase in knowledge based on the study of disease-born microorganisms’ genomes, the development of more representative disease models and improvement of techniques, technologies, and computation applied to biology are advances that will foster drug discovery in upcoming years. In this paper, several aspects of current methodologies for drug discovery of antibacterial and antifungals, anti-tropical diseases, antibiofilm and antiquorum sensing, anticancer and neuroprotectors are considered. For drug discovery, two different complementary approaches can be applied: classical pharmacology, also known as phenotypic drug discovery, which is the historical basis of drug discovery, and reverse pharmacology, also designated target-based drug discovery. Screening methods based on phenotypic drug discovery have been used to discover new natural products mainly from terrestrial origin. Examples of the discovery of marine natural products are provided. A section on future trends provides a comprehensive overview on recent advances that will foster the pharmaceutical industry.

A patent review of butyrylcholinesterase inhibitors and reactivators 2010-2017

INTRODUCTION

Butyrylcholinesterase (BuChE) has obtained a renewed interest as therapeutic target in Alzheimer's disease (AD), when changes in BuChE activity and expression along disease progression were highlighted as well as correlation between BuChE levels and cognitive function.

AREAS COVERED

During the last eight years, fourteen patents on BuChE inhibitors (BuChEI) have been submitted. Only three of them relate to BuChE selective inhibitors, while four of them focus on multitarget inhibitors which address different key pathological factors other than BuChE. Two patents report on non-selective acetylcholinesterase (AChE)/BuChE inhibitors, while four patents deal with natural compounds and their derivatives. One patent relates to antitoxic agents to treat exposure to ChEI pesticides and nerve agents.

EXPERT OPINION

Increasing evidence supports BuChE as a more beneficial target in moderate-to-severe forms of AD in comparison to the well-known AChE. However, hitting a single pathological target is likely not sufficient to halt the disease progression. Therefore, patented BuChE inhibitors with a multifunctional profile may open new therapeutic avenues, since the additional activities could reinforce the therapeutic effects. Unfortunately, in vivo studies are limited and key parameters, such as ADMET data, are missing. This lack of information makes difficult to forecast the development of patented BuChEIs into effective drug candidates.

Efficacy and Safety of MLC601 in Patients with Mild to Moderate Alzheimer Disease: An Extension 4-Year Follow-Up Study

Background and Aim

Alzheimer disease (AD) is the most common cause of dementia. Currently, there is no disease-modifying therapy for AD. We aimed to evaluate the long-term efficacy and safety of MLC601 in the treatment of AD.

Methods

In this open-label extension study, patients with mild to moderate AD according to DSM-IV criteria were recruited. Patients received MLC601 capsules 3 times a day for 4 years. Cognitive function was assessed every 6 months using Mini-Mental State Examination (MMSE) and Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog) scores. Safety profiles, including adverse events (AEs), and treatment-related abnormality in laboratory tests were also reported.

Results

Of a total of 122 patients, 105 completed the study. The mean age was 66.8 ± 6.3 years at the beginning of the study. Sixty-five (61.9%) were female. The mean (±SD) change in MMSE and ADAS-Cog scores at the end of the study was 2.1 (±3.8) and −5.1 (±8.7), respectively. Repeated measure analysis revealed a statistically significant change in both scores (p < 0.001). No patient left the study due to an AE. No abnormality was noted in lab tests. Gastrointestinal symptoms were the most commonly reported AEs.

Conclusion

The efficacy of treating AD patients with MLC601 over 4 years has been demonstrated in the present study. Overall, it seems that the safety and efficacy of MLC601 is promising compared to currently prescribed treatments.

Pentamethinium salts as ligands for cancer: Sulfated polysaccharide co-receptors as possible therapeutic target

A series of pentamethinium salts with benzothiazolium and indolium side units comprising one or two positive charges were designed and synthesized to determine the relationships among the molecular structure, charge density, affinity to sulfated polysaccharides, and biological activity. Firstly, it was found that the affinity of the pentamethinium salts to sulfated polysaccharides correlated with their biological activity. Secondly, the side heteroaromates displayed a strong effect on the cytotoxicity and selectivity towards cancer cells. Finally, doubly charged pentamethinium salts possessing benzothiazolium side units exhibited remarkably high efficacy against a taxol-resistant cancer cell line.

Multi-targeting effects of a new synthetic molecule (JM-20) in experimental models of cerebral ischemia

Ischemic stroke is a major cause of death and disability worldwide. Thrombolysis by tissue plasminogen activator is the only pharmacological treatment approved for clinical practice, but has a narrow therapeutic window and poor efficacy when the cell death cascade is activated. Numerous drugs that are thought to protect neurons against injury have previously failed in human trials despite showing efficacy in experimental models of stroke. Herein, we reviewed the main pre-clinical results of the neuroprotective effects of JM-20, a new hybrid molecule, against brain ischemia. JM-20 appears to protect the brain from ischemic damage by interfering with several elements of the ischemic cascade: antiexcitotoxic, anticalcic, antioxidant, antiapoptotic, and anti-inflammatory. Its ability to protect not only neurons but also glial cells together with its ability to target and preserve mitochondrial function makes JM-20 a promising molecule that may be able to shield the whole neurovascular unit. The multimodal and multi-cell action of JM-20 may explain the high degree of protection observed in a rat model of brain ischemia, as assayed through histological (hematoxylin-eosin, and luxol fast blue staining), neurochemical (glutamate and aspartate levels in cerebrospinal fluid), mitochondrial functionality and behavioural (neurological scale) analysis at doses of 4 and 8mg/kg. Furthermore, the wide therapeutic window of JM-20 of 8h also suggests that this molecule could be of potential interest in situations where brain perfusion is compromised.

Synthesis and Biological Evaluation of Pentacycloundecylamines and Triquinylamines as Voltage-Gated Calcium Channel Blockers

Preclinical studies for neurodegenerative diseases have shown a multi-targeted approach to be successful in the treatment of these complex disorders with several pathoetiological pathways. Polycyclic compounds, such as NGP1-01 (7a), have demonstrated the ability to target multiple mechanisms of the complex etiology and are referred to as multifunctional compounds. These compounds have served as scaffolds with the ability to attenuate Ca(2+) overload and excitotoxicity through several pathways. In this study, our focus was on mitigating Ca(2+) overload through the L-type calcium channels (LTCC). Here, we report the synthesis and biological evaluation of several novel polycyclic compounds. We determined the IC50 values for both the pentacycloundecylamines and the triquinylamines by means of a high-throughput fluorescence calcium flux assay utilizing Fura-2/AM. The potential of these compounds to offer protection against hydrogen peroxide-induced cell death was also evaluated. Overall, 8-benzylamino-8,11-oxapentacyclo[5.4.0.0(2,6) .0(3,10) .0(5,9) ]undecane (NGP1-01, 7a) had the most favorable pharmacological profile with an IC50 value of 86 µM for LTCC inhibition and significant reduction of hydrogen peroxide-induced cell death. In general, the triquinylamines were more active as LTCC blockers than the oxa-pentacycloundecylamines. The aza-pentacycloundecylamines were potent LTCC inhibitors, with 8-hydroxy-N-phenylethyl-8,11-azapentacyclo[5.4.0.0(2,6) .0(3,10) .0(5,9) ]undecane (8b) also able to offer significant protection in the cell viability assays.