Evaluation of rivastigmine in Alzheimer's disease

Herbgenomics meets Papaveraceae: a promising -omics perspective on medicinal plant research

Herbal medicines were widely used in ancient and modern societies as remedies for human ailments. Notably, the Papaveraceae family includes well-known species, such as Papaver somniferum and Chelidonium majus, which possess medicinal properties due to their latex content. Latex-bearing plants are a rich source of diverse bioactive compounds, with applications ranging from narcotics to analgesics and relaxants. With the advent of high-throughput technologies and advancements in sequencing tools, an opportunity exists to bridge the knowledge gap between the genetic information of herbs and the regulatory networks underlying their medicinal activities. This emerging discipline, known as herbgenomics, combines genomic information with other -omics studies to unravel the genetic foundations, including essential gene functions and secondary metabolite biosynthesis pathways. Furthermore, exploring the genomes of various medicinal plants enables the utilization of modern genetic manipulation techniques, such as Clustered Regularly-Interspaced Short Palindromic Repeats (CRISPR/Cas9) or RNA interference. This technological revolution has facilitated systematic studies of model herbs, targeted breeding of medicinal plants, the establishment of gene banks and the adoption of synthetic biology approaches. In this article, we provide a comprehensive overview of the recent advances in genomic, transcriptomic, proteomic and metabolomic research on species within the Papaveraceae family. Additionally, it briefly explores the potential applications and key opportunities offered by the -omics perspective in the pharmaceutical industry and the agrobiotechnology field.

In silico and pharmacokinetic studies of glucomoringin from Moringa oleifera root for Alzheimer's disease like pathology

Aim: The aim of this research is to investigate the potential of glucomoringin, derived from Moringa oleifera, as a therapeutic agent for Alzheimer's disease through in silico analysis. Materials & methods: This study employs in silico or computational methodologies, including pkCSM, Swiss ADME, OSIRIS® property explorer, PASS online web resource and MOLINSPIRATION® software, to predict the pharmacokinetic characteristics and biological activity of glucomoringin. Results & conclusion: Molecular docking indicates strong binding to I-1β and the pharmacokinetic profile shows cytochrome P450 enzyme inhibition, prompting further research for dosing strategies. Toxicological predictions affirm safety, while bioactivity assessments demonstrate versatility in modulating essential pathways. glucomoringin's potential for Alzheimer's treatment, emphasizing the need for additional empirical research.

Synthesis and molecular docking studies of 5-trifluoromethoxy-2-indolinones as cholinesterase dual inhibitors

Background: In Alzheimer's disease, butyrylcholinesterase (BuChE) activity gradually increases, while acetylcholinesterase (AChE) activity decreases or remains unchanged. Dual inhibitors have important roles in regulation of synaptic acetylcholine levels and progression of Alzheimer's disease. Methods: 1-(Thiomorpholin-4-ylmethyl)/benzyl-5-trifluoromethoxy-2-indolinones (6-7) were synthesized. AChE and BuChE inhibitory effects were investigated with Ellman's method. Molecular docking studies were performed for analyzing the possible binding interactions at active sites. Results: Compound 6g was the strongest inhibitor against both AChE (Ki = 0.35 μM) and BuChE (Ki = 0.53 μM). It showed higher inhibitory effects than both donepezil and galantamine. Moreover, compound 7m had a higher inhibitory effect than galantamine and the effect was comparable to that of donepezil against both AChE (Ki = 0.69 μM) and BuChE (Ki = 0.95 μM). Conclusion: The benzyl substitution compared with 1-(thiomorpholin-4-ylmethyl) group significantly increased both AChE and BuChE inhibitory effects.

Effects of Medicare Part D medication therapy management on racial/ethnic disparities in adherence to antidementia medications among patients with Alzheimer's disease and related dementias: An observational study

Background

Evidence is sparse on the effects of Medicare medication therapy management (MTM) on racial/ethnic disparities in medication adherence among patients with Alzheimer's disease and related dementias.

Objectives

This study examined the Medicare MTM program's effects on racial/ethnic disparities in the adherence to antidementia medications among patients with Alzheimer's disease and related dementias.

Methods

This is a retrospective analysis of 100% of 2010-2017 Medicare Parts A, B, and D data linked to Area Health Resources Files. The study outcome was nonadherence to antidementia medications, and intervention was defined as new MTM enrollment in 2017. Propensity score matching was conducted to create intervention and comparison groups with comparable characteristics. A difference-in-differences model was employed with logistic regression, including interaction terms of dummy variables for the intervention group and racial/ethnic minorities.

Results

Unadjusted comparisons revealed that Black, Hispanic, and Asian/Pacific Islander patients were more likely to be nonadherent than non-Hispanic White (White) patients in 2016. Differences in odds of nonadherence between Black and White patients among the intervention group were lower in 2017 than in 2016 by 27% (odds ratios [OR]: 0.73, 95% confidence interval [CI]: 0.65-0.82). A similar lowering was seen between Hispanic and White patients by 26% (OR: 0.74, 95% CI: 0.63-0.87). MTM enrollment was associated with reduced disparities in nonadherence for Black-White patients of 33% (OR: 0.67, 95% CI: 0.57-0.78) and Hispanic-White patients of 19% (OR: 0.81, 95% CI: 0.67-0.99).

Discussion

The Medicare MTM program was associated with lower disparities in adherence to antidementia medications between Black and White patients, and between Hispanic and White patients in the population with Alzheimer's disease and related dementias.

Conclusions

Expanding the MTM program may particularly benefit racial/ethnic minorities in Alzheimer's disease and related dementia care.

Design, synthesis and evaluation of quinoline-O-carbamate derivatives as multifunctional agents for the treatment of Alzheimer's disease

A series of novel quinoline-O-carbamate derivatives was rationally designed for treating Alzheimer's disease (AD) by multi-target-directed ligands (MTDLs) strategy. The target compounds were synthesised and evaluated by AChE/BuChE inhibition and anti-inflammatory property. The in vitro activities showed that compound 3f was a reversible dual eeAChE/eqBuChE inhibitor with IC₅₀ values of 1.3 µM and 0.81 µM, respectively. Moreover, compound 3f displayed good anti-inflammatory property by decreasing the production of IL-6, IL-1β and NO. In addition, compound 3f presented significant neuroprotective effect on Aβ_25-35-induced PC12 cell injury. Furthermore, compound 3f presented good stabilities in artificial gastrointestinal fluids, liver microsomes in vitro and plasma. Furthermore, compound 3f could improve AlCl₃-induced zebrafish AD model by increasing the level of ACh. Therefore, compound 3f was a promising multifunctional agent for the treatment of AD.

Neuroprotective Mechanisms of Salidroside in Alzheimer's Disease: A Systematic Review and Meta-analysis of Preclinical Studies

Alzheimer's disease (AD) is a neurodegenerative disease of the central nervous system that occurs in old age and pre-aging, characterized by progressive cognitive dysfunction and behavioral impairment. Salidroside (Sal) is a phenylpropanoid mainly isolated from Rhodiola species with various pharmacological effects. However, the exact anti-AD mechanism of Sal has not been clearly elucidated. This meta-analysis aims to investigate the possible mechanisms by which Sal exerts its anti-AD effects by evaluating behavioral indicators and biochemical characteristics. A total of 20 studies were included, and the results showed that the Sal treatment significantly improved behavior abnormalities in AD animal models. With regard to neurobiochemical indicators, Sal treatment could effectively increase the antioxidant enzyme superoxide dismutase, decrease the oxidative stress indicator malondialdehyde, and decrease the inflammatory indicators interleukin 1β, interleukin 6, and tumor necrosis factor α. Sal treatment was effective in reducing neuropathological indicators, such as amyloid-β levels and the number of apoptotic cells. When the relevant literature on the treatment of rodent AD models is combined with Sal, the therapeutic potential of Sal through multiple mechanisms was confirmed. However, further confirmation by higher quality studies, larger sample sizes, and more comprehensive outcome evaluations in clinical trials is needed in the future.

ApoE3 Anchored Liposomal Delivery of Rivastigmine for Brain Delivery: Formulation, Characterization, and In Vivo Pharmacokinetic Evaluation

Rivastigmine hydrogen tartrate (RHT) is an acetylcholinesterase (AChE) inhibitor used in the management of Alzheimer's disease (AD). RHT is a BCS class-I drug that undergoes significant first-pass metabolism. Permeating a hydrophilic drug through the brain remains a major challenge in brain delivery. In this study, the RHT was incorporated inside the hydrophilic core of liposomes (LPS) and then coated with the ApoE3. ApoE3-coated RHT-loaded liposomes (ApoE3-RHT-LPS) were fabricated through the thin film hydration method using DSPE-PEG. The coating of LPS with ApoE3 enhances brain uptake and improves Aβ clearance. The results obtained from the physicochemical characterization demonstrated that ApoE3-RHT-LPS shows a particle size of 128.6 ± 2.16 nm and a zeta potential of 16.6 ± 1.19. The % entrapment efficiency and % drug loading were found to be 75% and 17.84%, respectively. The data obtained from TEM and SEM studies revealed that the particle size of the LPS was less than 200 nm. An in vitro AChE assay was performed, and the results demonstrated the AChE inhibitory potential of ApoE3-RHT-LPS. Through the intravenous route, an in vivo pharmacokinetic study of formulation displayed improved brain uptake of RHT by ~ 1.3-fold than pure RHT due to ApoE3 coating. In vivo, biodistribution studies in vital organs suggested that the biodistribution of RHT to the liver was significantly reduced (p < 0.001), signifying an increase in the drug's half-life and blood circulation time. All research findings suggested that ApoE3 coating and LPS strategy are proven effective for improving the brain uptake of RHT designed for the management of AD.

Neuroprotective Agents with Therapeutic Potential for COVID-19

COVID-19 patients can exhibit a wide range of clinical manifestations affecting various organs and systems. Neurological symptoms have been reported in COVID-19 patients, both during the acute phase of the illness and in cases of long-term COVID. Moderate symptoms include ageusia, anosmia, altered mental status, and cognitive impairment, and in more severe cases can manifest as ischemic cerebrovascular disease and encephalitis. In this narrative review, we delve into the reported neurological symptoms associated with COVID-19, as well as the underlying mechanisms contributing to them. These mechanisms include direct damage to neurons, inflammation, oxidative stress, and protein misfolding. We further investigate the potential of small molecules from natural products to offer neuroprotection in models of neurodegenerative diseases. Through our analysis, we discovered that flavonoids, alkaloids, terpenoids, and other natural compounds exhibit neuroprotective effects by modulating signaling pathways known to be impacted by COVID-19. Some of these compounds also directly target SARS-CoV-2 viral replication. Therefore, molecules of natural origin show promise as potential agents to prevent or mitigate nervous system damage in COVID-19 patients. Further research and the evaluation of different stages of the disease are warranted to explore their potential benefits.

Liposome-Derived Nanosystems for the Treatment of Behavioral and Neurodegenerative Diseases: The Promise of Niosomes, Transfersomes, and Ethosomes for Increased Brain Drug Bioavailability

Psychiatric and neurodegenerative disorders are amongst the most prevalent and debilitating diseases, but current treatments either have low success rates, greatly due to the low permeability of the blood-brain barrier, and/or are connected to severe side effects. Hence, new strategies are extremely important, and here is where liposome-derived nanosystems come in. Niosomes, transfersomes, and ethosomes are nanometric vesicular structures that allow drug encapsulation, protecting them from degradation, and increasing their solubility, permeability, brain targeting, and bioavailability. This review highlighted the great potential of these nanosystems for the treatment of Alzheimer's disease, Parkinson's disease, schizophrenia, bipolar disorder, anxiety, and depression. Studies regarding the encapsulation of synthetic and natural-derived molecules in these systems, for intravenous, oral, transdermal, or intranasal administration, have led to an increased brain bioavailability when compared to conventional pharmaceutical forms. Moreover, the developed formulations proved to have neuroprotective, anti-inflammatory, and antioxidant effects, including brain neurotransmitter level restoration and brain oxidative status improvement, and improved locomotor activity or enhancement of recognition and working memories in animal models. Hence, albeit being relatively new technologies, niosomes, transfersomes, and ethosomes have already proven to increase the brain bioavailability of psychoactive drugs, leading to increased effectiveness and decreased side effects, showing promise as future therapeutics.

Oxymatrine-mediated prevention of amyloid β-peptide-induced apoptosis on Alzheimer's model PC12 cells: in vitro cell culture studies and in vivo cognitive assessment in rats

Alzheimer's disease (AD) is a major neurological disease affecting elderly individuals worldwide. Existing drugs only reduce the symptoms of the disease without addressing the underlying causes. Commonly, Aβ25-35 peptide aggregation is the main reason for AD development. Recently, the discovery of multiple protein-targeting molecules has provided a new strategy for treating AD. This study demonstrates the neuroprotective potential of oxymatrine against multiple mechanisms, such as acetylcholinesterase, mitochondrial damage, and β-amyloid-induced cell toxicity. The in vitro cell culture studies showed that oxymatrine possesses significant potential to inhibit acetylcholine esterase and promotes antioxidant, antiapoptotic effects while preventing Aβ25-35 peptide aggregation in PC12 cells. Furthermore, oxymatrine protects PC12 cells against Aβ25-35-induced cytotoxicity and down-regulates the reactive oxygen species generation. The in vivo acute toxicological studies confirm the safety of oxymatrine without causing organ damage or death in animals. Overall, this study provided evidence that oxymatrine is an efficient neuroprotective agent, with a potential to be a multifunctional drug for Alzheimer's disease treatment. These findings present a reliable and synergistic approach for treating AD.

Intranasal Drug Administration in Alzheimer-Type Dementia: Towards Clinical Applications

Alzheimer-type dementia (ATD) treatments face limitations in crossing the blood-brain barrier and systemic adverse effects. Intranasal administration offers a direct route to the brain via the nasal cavity's olfactory and trigeminal pathways. However, nasal physiology can hinder drug absorption and limit bioavailability. Therefore, the physicochemical characteristics of formulations must be optimized by means of technological strategies. Among the strategies that have been explored, lipid-based nanosystems, particularly nanostructured lipid carriers, are promising in preclinical investigations with minimal toxicity and therapeutic efficacy due to their ability to overcome challenges associated with other nanocarriers. We review the studies of nanostructured lipid carriers for intranasal administration in the treatment of ATD. Currently, no drugs for intranasal administration in ATD have marketing approval, with only three candidates, insulin, rivastigmine and APH-1105, being clinically investigated. Further studies with different candidates will eventually confirm the potential of the intranasal route of administration in the treatment of ATD.

Kaempferol as a therapeutic agent in Alzheimer's disease: Evidence from preclinical studies

BACKGROUND

Alzheimer's disease (AD) is the most common type of dementia and seriously affects human life and health. Kaempferol (KMP) is a common flavonoid, that is mainly derived from the rhizomes of Kaempferol galanga L. and is widely found in various fruits and vegetables. Previous studies have suggested that KMP has multiple pharmacological activities. However, the anti-AD mechanism of KMP has not been elucidated.

METHODS

This systematic review aims to summarize the existing preclinical experiments on KMP, further confirm the therapeutic effect of KMP in an AD model, and summarize the possible mechanism by which KMP exerts anti-AD effects. Electronic databases, including PubMed, China National Knowledge Infrastructure (CNKI), Baidu Academic, and Wanfang, were searched using the keywords of 'Kaempferol,' 'KMP,' 'pharmacology,' and 'Alzheimer's disease'.

RESULTS

We evaluated the reliability of the 12 included studies, and the results showed that the anti-AD mechanism of KMP was reliable and that the prospect of KMP in the treatment of cognitive impairment was promising. We comprehensively assessed the neuroprotective effects of KMP in in vivo and in vitro models of AD. These studies shown that KMP ameliorated AD through several mechanisms, including its antioxidant, anti-inflammatory, anti-apoptotic, and anti-acetylcholinesterase effects.

CONCLUSION

KMP may exert anti-AD effects through various mechanisms and is a potential drug with broad prospects for the treatment of AD.

Photobiomodulation in Alzheimer's Disease-A Complementary Method to State-of-the-Art Pharmaceutical Formulations and Nanomedicine?

Alzheimer's disease (AD), as a neurodegenerative disorder, usually develops slowly but gradually worsens. It accounts for approximately 70% of dementia cases worldwide, and is recognized by WHO as a public health priority. Being a multifactorial disease, the origins of AD are not satisfactorily understood. Despite huge medical expenditures and attempts to discover new pharmaceuticals or nanomedicines in recent years, there is no cure for AD and not many successful treatments are available. The current review supports introspection on the latest scientific results from the specialized literature regarding the molecular and cellular mechanisms of brain photobiomodulation, as a complementary method with implications in AD. State-of-the-art pharmaceutical formulations, development of new nanoscale materials, bionanoformulations in current applications and perspectives in AD are highlighted. Another goal of this review was to discover and to speed transition to completely new paradigms for the multi-target management of AD, to facilitate brain remodeling through new therapeutic models and high-tech medical applications with light or lasers in the integrative nanomedicine of the future. In conclusion, new insights from this interdisciplinary approach, including the latest results from photobiomodulation (PBM) applied in human clinical trials, combined with the latest nanoscale drug delivery systems to easily overcome protective brain barriers, could open new avenues to rejuvenate our central nervous system, the most fascinating and complex organ. Picosecond transcranial laser stimulation could be successfully used to cross the blood-brain barrier together with the latest nanotechnologies, nanomedicines and drug delivery systems in AD therapy. Original, smart and targeted multifunctional solutions and new nanodrugs may soon be developed to treat AD.

Biological Evaluation of Valeriana Extracts from Argentina with Potent Cholinesterase Inhibition for the Treatment of Neurodegenerative Disorders and Their Comorbidities-The Case of Valeriana carnosa Sm. (Caprifoliaceae) Studied in Mice

Alzheimer's disease (AD) is a neurodegenerative disorder whose pathophysiology includes the abnormal accumulation of proteins (e.g., β-amyloid), oxidative stress, and alterations in neurotransmitter levels, mainly acetylcholine. Here we present a comparative study of the effect of extracts obtained from endemic Argentinian species of valerians, namely V. carnosa Sm., V. clarionifolia Phil. and V. macrorhiza Poepp. ex DC from Patagonia and V. ferax (Griseb.) Höck and V. effusa Griseb., on different AD-related biological targets. Of these anxiolytic, sedative and sleep-inducing valerians, V. carnosa proved the most promising and was assayed in vivo. All valerians inhibited acetylcholinesterase (IC₅₀ between 1.08-12.69 mg/mL) and butyrylcholinesterase (IC₅₀ between 0.0019-1.46 mg/mL). They also inhibited the aggregation of β-amyloid peptide, were able to chelate Fe²⁺ ions, and exhibited a direct relationship between antioxidant capacity and phenolic content. Moreover, V. carnosa was able to inhibit human monoamine oxidase A (IC₅₀: 0.286 mg/mL (0.213-0.384)). A daily intake of aqueous V. carnosa extract by male Swiss mice (50 and 150 mg/kg/day) resulted in anxiolytic and antidepressant-like behavior and improved spatial memory. In addition, decreased AChE activity and oxidative stress markers were observed in treated mouse brains. Our studies contribute to the development of indigenous herbal medicines as therapeutic agents for AD.

Synthesis and molecular modeling studies of 1-benzyl-2-indolinones as selective AChE inhibitors

Background: Possible bioisosteres can be developed by replacing the 1-indanone ring (one of three pharmacophore groups) of donepezil with an indoline ring. As H₂S donors, thioamide, thiocarbamate and thiourea groups are also critically important. Materials & methods: The 1-benzyl-2-indolinones 6a-n were designed using molecular modeling and synthesized, and their acetylcholinesterase and butyrylcholinesterase inhibitory effects were then investigated. Results: The compounds 6h (inhibition constant [K_i] = 0.22 μM; selectivity index [SI] = 26.22), 6i (K_i = 0.24 μM; SI = 25.83), 6k (K_i = 0.22 μM; SI = 28.31) and 6n (K_i = 0.21 μM; SI = 27.14) were approximately twofold more effective against and >12-fold more selective for acetylcholinesterase compared with donepezil (K_i = 0.41 μM; SI = 2.12). Analysis of molecular dynamics simulations with compounds 6k and 6n indicated that the preferred binding might be at allosteric binding pocket 4 of the enzyme. Conclusion: Benzyl substitution at the 1-position of the indole ring significantly increased potency and selectivity.

Design, Synthesis and Biological Evaluation of Biscarbamates as Potential Selective Butyrylcholinesterase Inhibitors for the Treatment of Alzheimer's Disease

As butyrylcholinesterase (BChE) plays a role in the progression of symptoms and pathophysiology of Alzheimer's disease (AD), selective inhibition of BChE over acetylcholinesterase (AChE) can represent a promising pathway in treating AD. The carbamate group was chosen as a pharmacophore because the carbamates currently or previously in use for the treatment of AD displayed significant positive effects on cognitive symptoms. Eighteen biscarbamates with different substituents at the carbamoyl and hydroxyaminoethyl chain were synthesized, and their inhibitory potential toward both cholinesterases and inhibition selectivity were determined. The ability of carbamates to cross the blood-brain barrier (BBB) by passive transport, their cytotoxic profile and their ability to chelate biometals were also evaluated. All biscarbamates displayed a time-dependent inhibition with inhibition rate constants within 10^-3-10^-6 M^-1 min^-1 range for both cholinesterases, with generally higher preference to BChE. For two biscarbamates, it was determined that they should be able to pass the BBB by passive transport, while for five biscarbamates, this ability was slightly limited. Fourteen biscarbamates did not exhibit a cytotoxic effect toward liver, kidney and neuronal cells. In conclusion, considering their high BChE selectivity, non-toxicity, ability to chelate biometals and pass the BBB, compounds 2 and 16 were pointed out as the most promising compounds for the treatment of middle and late stages of AD.

New Possibilities in the Therapeutic Approach to Alzheimer's Disease

Despite the fact that Alzheimer's disease (AD) is the most common cause of dementia, after many years of research regarding this disease, there is no casual treatment. Regardless of the serious public health threat it poses, only five medical treatments for Alzheimer's disease have been authorized, and they only control symptoms rather than changing the course of the disease. Numerous clinical trials of single-agent therapy did not slow the development of disease or improve symptoms when compared to placebo. Evidence indicates that the pathological alterations linked to AD start many years earlier than a manifestation of the disease. In this pre-clinical period before the neurodegenerative process is established, pharmaceutical therapy might prove invaluable. Although recent findings from the testing of drugs such as aducanumab are encouraging, they should nevertheless be interpreted cautiously. Such medications may be able to delay the onset of dementia, significantly lowering the prevalence of the disease, but are still a long way from having a clinically effective disease-modifying therapy.

Adenosine ameliorated Aβ25-35-induced brain injury through the inhibition of apoptosis and oxidative stress via an ERα pathway

Previous studies have shown that adenosine has estrogen-like activity mediated by estrogen receptor α (ERɑ). This study aimed to examine the effects of adenosine on Aβ_25-35-induced brain injury and the underlying mechanisms involved. Adenosine (Ade, 20 mg/kg, i.g.) was administered for four weeks, followed by the induction of Alzheimer's disease (AD) by Aβ_25-35 (200 µM, 3 µL/20 g, i.c.v.). Furthermore, a specific ERα blocker (MPP, 0.3 mg/kg, i.p.) was administered 30 min before the treatments of adenosine to evaluate whether the observed effects elicited by adenosine were mediated via ERα. In addition, the learning and memory ability, neuronal damage, and the levels of amyloid β-protein (Aβ), phosphorylated Tau Protein (p-Tau), apoptosis, oxidative stress, immune cells, and ERα were examined. The antagonistic effect of MPP (1 µM) against adenosine (5 µM) in Aβ_25-35 (20 µM, 24 h)-induced N9 and PC-12 cells was also investigated. Adenosine improved learning and memory ability, reduced neuronal damage, downregulated Aβ₄₂/Aβ₄₀, p-Tau, apoptosis, and oxidative stress, transformed immune cells, and increased the expression of ERα following Aβ_25-35 challenge. MPP could block these effects. Moreover, MPP also blocked the effects of adenosine on the levels of apoptosis and reactive oxygen species (ROS) in Aβ_25-35-induced N9 and PC-12 cells. Adenosine ameliorated Aβ_25-35-induced brain injury by inhibiting apoptosis and oxidative stress, possibly via an ERα pathway.

Scalable Functionalization of Polyaniline-Grafted rGO Field-Effect Transistors for a Highly Sensitive Enzymatic Acetylcholine Biosensor

For decades, acetylcholine (Ach) has been considered a critical biomarker for several degenerative brain diseases, including Alzheimer’s, Parkinson’s disease, Huntington’s disease, and schizophrenia. Here, we propose a wafer-scale fabrication of polyaniline (PAni)-grafted graphene-based field-effect transistors (PGFET) and their biosensing applications for highly sensitive and reliable real-time monitoring of Ach in flow configuration. The grafted PAni provides suitable electrostatic binding sites for enzyme immobilization and enhances the pH sensitivity (2.68%/pH), compared to that of bare graphene-FET (1.81%/pH) for a pH range of 3–9 without any pH-hysteresis. We further evaluated the PGFET’s sensing performance for Ach detection with a limit of detection at the nanomolar level and significantly improved sensitivity (~103%) in the concentration range of 108 nM to 2 mM. Moreover, the PGFET exhibits excellent selectivity against various interferences, including glucose, ascorbic acid, and neurotransmitters dopamine and serotonin. Finally, we investigated the effects of an inhibitor (rivastigmine) on the AchE activity of the PGFET. From the results, we demonstrated that the PGFET has great potential as a real-time drug-screening platform by monitoring the inhibitory effects on enzymatic activity.

The Role of Resveratrol in Mild Cognitive Impairment and Alzheimer's Disease: A Systematic Review

Advancing age is one of the risk factors for developing many diseases, including cancer, cardiovascular disorders, and neurodegenerative alterations, such as mild cognitive impairment (MCI), and Alzheimer's Disease (AD). Studies have indicated that supplementation with resveratrol (RSV) might improve cerebrovascular function and reduce the risk of developing dementia. Thus, the aim of this systematic review was to assess the effects of RSV on MCI and AD. MEDLINE-PubMed, Cochrane, and EMBASE were used to perform the search, and PRISMA guidelines were followed. Five studies met the eligible criteria; three with AD and two with MCI. In AD patients, the use of RSV reduces Aβ levels, improves brain volume, reduces the Mini-mental status score, and improves AD scores. In patients with MCI, this polyphenol prevents decline in Standard Volumes of Interest and increases the Resting-state Functional Connectivity score. RSV can activate the human silent information regulator 2/sirtuin 1 (Sirt-1) and can inhibit the cyclooxygenase-2 (COX-2), 5-lipoxygenase, and nuclear factor-κB, resulting in the reduction of the proinflammation pathways. It is also associated with the increase in the levels of interleukin (IL)-10 and reduction of interferon-γ and IL-17. Both anti-inflammatory and antioxidant effects can be related to preventing neurodegenerative diseases, doing maintenance, and enabling the recovery of these conditions directly related to inflammation and oxidative stress. We suggest that the use of RSV can bring beneficial effects to patients with MCI or AD.

Molecular Insights into Therapeutic Potentials of Hybrid Compounds Targeting Alzheimer's Disease

Alzheimer's disease (AD) is one of the most complex progressive neurological disorders involving degeneration of neuronal connections in brain cells leading to cell death. AD is predominantly detected among elder people (> 65 years), mostly diagnosed with the symptoms of memory loss and cognitive dysfunctions. The multifarious pathogenesis of AD comprises the accumulation of pathogenic proteins, decreased neurotransmission, oxidative stress, and neuroinflammation. The conventional therapeutic approaches are limited to symptomatic benefits and are ineffective against disease progression. In recent years, researchers have shown immense interest in the designing and fabrication of various novel therapeutics comprised of naturally isolated hybrid molecules. Hybrid therapeutic compounds are developed from the combination of pharmacophores isolated from bioactive moieties which specifically target and block various AD-associated pathogenic pathways. The method of designing hybrid molecules has numerous advantages over conventional multitarget drug development methods. In comparison to in silico high throughput screening, hybrid molecules generate quicker results and are also less expensive than fragment-based drug development. Designing hybrid-multitargeted therapeutic compounds is thus a prospective approach in developing an effective treatment for AD. Nevertheless, several issues must be addressed, and additional researches should be conducted to develop hybrid therapeutic compounds for clinical usage while keeping other off-target adverse effects in mind. In this review, we have summarized the recent progress on synthesis of hybrid compounds, their molecular mechanism, and therapeutic potential in AD. Using synoptic tables, figures, and schemes, the review presents therapeutic promise and potential for the development of many disease-modifying hybrids into next-generation medicines for AD.

Challenges and approaches of drugs such as Memantine, Donepezil, Rivastigmine and Aducanumab in the treatment, control and management of Alzheimer's disease

Alzheimer's disease (AD) is a kinds of neuropsychiatric illnesses that affect the central nervous system. In this disease, the accumulation of amyloid-beta increases, and phosphorylated tau (P-tau) protein, one of the ways to treat this disease is to reduce the accumulation of amyloid-beta. Various studies have demonstrated that pharmacological approaches have considerable effects in the treatment of AD, despite the side effects and challenges. Cholinesterase inhibitors and the NMDA receptor antagonist memantine are presently authorized therapies for AD. Memantine and Donepezil are the most common drugs for the prevention and therapy of AD with mechanisms such as lessened β-amyloid plaque, effect on N-Methyl-D-aspartate (NMDA) receptors. Diminution glutamate and elevated acetylcholine are some of the influences of medications administrated to treat AD, and drugs can also play a role in slowing the progression of cognitive and memory impairment. A new pharmacological approach and strategy is required to control the future of AD. This review appraises the effects of memantine, donepezil, rivastigmine, and aducanumab in clinical trials, in vitro and animal model studies that have explored how these drugs versus AD development and also discuss possible mechanisms of influence on the brain. Research in clinical trials has substantial findings that support the role of these medications in AD treatment and ameliorate the safety and efficacy of AD therapy, although more clinical trials are required to prove their effectiveness.

Polypharmacy and Mental Health Issues in the Senior Hemodialysis Patient

Hemodialysis (HD) is the most common method of chronic kidney failure (CKF) treatment, with 65% of European patients with CKF receiving HD in 2018. Regular two to three HD sessions weekly severely lower their quality of life, resulting in a higher incidence of depression and anxiety, which is present in one third to one half of these patients. Additionally, the age of patients receiving HD is increasing with better treatment and care, resulting in more cognitive impairment being uncovered. Lastly, patients with other mental health issues can also develop CKF during their life with need for kidney replacement therapy (KRT). All these conditions need to receive adequate care, which often means prescribing psychotropic medications. Importantly, many of these drugs are eliminated through the kidneys, which results in altered pharmacokinetics when patients receive KRT. This narrative review will focus on common issues and medications of CKF patients, their comorbidities, mental health issues, use of psychotropic medications and their altered pharmacokinetics when used in HD, polypharmacy, and drug interactions, as well as deprescribing algorithms developed for these patients.

The Potential Effect of Insulin on AChE and Its Interactions with Rivastigmine In Vitro

There is no definite cure for Alzheimer’s disease (AD) due to its multifactorial origin. Drugs that inhibit acetylcholinesterase (AChE), such as rivastigmine, are promising symptomatic treatments for AD. Emerging evidence suggests that insulin therapy can hinder several aspects of AD pathology. Insulin has been shown to modify the activity of AChE, but it is still unknown how insulin and AChE interact. Combination therapy, which targets several features of the disease based on existing medications, can provide a worthy therapy option for AD management. However, to date, no studies have examined the potential interaction of insulin with AChE and/or rivastigmine in vitro. In the present study, we employed the Response Surface Methodology (RSM) as an in vitro assessment to investigate the effect of insulin on both AChE activity and rivastigmine inhibitory action using a common spectrophotometric assay for cholinesterase activity, Ellman’s method. Our results showed that insulin, even at high concentrations, has an insignificant effect on both the activity of AChE and rivastigmine’s inhibitory action. The variance of our data is near zero, which means that the dispersion is negligible. However, to improve our understanding of the possible interaction of insulin and rivastigmine, or its target AChE, more in silico modelling and in vivo studies are needed.

Acetylcholinesterase Inhibitors in the Treatment of Neurodegenerative Diseases and the Role of Acetylcholinesterase in their Pathogenesis

Acetylcholinesterase (AChE) plays an important role in the pathogenesis of neurodegenerative diseases by influencing the inflammatory response, apoptosis, oxidative stress and aggregation of pathological proteins. There is a search for new compounds that can prevent the occurrence of neurodegenerative diseases and slow down their course. The aim of this review is to present the role of AChE in the pathomechanism of neurodegenerative diseases. In addition, this review aims to reveal the benefits of using AChE inhibitors to treat these diseases. The selected new AChE inhibitors were also assessed in terms of their potential use in the described disease entities. Designing and searching for new drugs targeting AChE may in the future allow the discovery of therapies that will be effective in the treatment of neurodegenerative diseases.

Memantine and Its Combination with Acetylcholinesterase Inhibitors in Pharmacological Pretreatment of Soman Poisoning in Mice

Nerve agents pose a real threat to both the military and civil populations, but the current treatment of the poisoning is unsatisfactory. Thus, we studied the efficacy of prophylactic use of memantine alone or in combination with clinically used reversible acetylcholinesterase inhibitors (pyridostigmine, donepezil, rivastigmine) against soman. In addition, we tested their influence on post-exposure therapy consisting of atropine and asoxime. Pyridostigmine alone failed to decrease the acute toxicity of soman. But all clinically used acetylcholinesterase inhibitors administered alone reduced the acute toxicity, with donepezil showing the best efficacy. The combination of memantine with reversible acetylcholinesterase inhibitors attenuated soman acute toxicity significantly. The pretreatment administered alone or in combinations influenced the efficacy of post-exposure treatment in a similar fashion: (i) pyridostigmine or memantine alone did not affect the antidotal treatment, (ii) centrally acting reversible acetylcholinesterase inhibitors alone increased the antidotal treatment slightly, (iii) combination of memantine with reversible acetylcholinesterase inhibitors increased the antidotal treatment more markedly. In conclusion, memantine alone failed to decrease the acute toxicity of soman or increase post-exposure antidotal treatment efficacy. The combination of memantine with donepezil significantly increased post-exposure effectiveness (together 5.12, pretreatment alone 1.72). Both drugs, when applied together, mitigate soman toxicity and boost post-exposure treatment.

The State of The Art on Acetylcholinesterase Inhibitors in the Treatment of Alzheimer's Disease

Alzheimer's disease (AD) is a chronic disabling disease that affects the central nervous system. The main consequences of AD include the decline of cognitive functions and language disorders. One of the causes leading to AD is the decrease of neurotransmitter acetylcholine (ACh) levels in the brain, in part due to a higher activity of acetylcholinesterase (AChE), the enzyme responsible for its degradation. Many acetylcholinesterase inhibitors (AChEIs), both natural and synthetic, have been developed and used through the years to counteract the progression of the disease. The first of such drugs approved for a therapeutic use was tacrine, that binds through a reversible bond to the enzyme. However, tacrine has since been withdrawn because of its adverse effects. Currently, donepezil and galantamine are very promising AChEIs with clinical benefits. Moreover, rivastigmine is considered a pseudo-irreversible compound with anti-AChE action, providing similar effects at the clinical level. The purpose of this review is to provide an overview of what has been published over the last decade on the effectiveness of AChEIs in AD, analysing the most relevant issues under the clinical and methodological profiles and the consequent possible welfare effects for the whole world. Furthermore, novel drugs and possible therapeutic approaches are also discussed.

Personalizing the Care and Treatment of Alzheimer's Disease: An Overview

Alzheimer's disease (AD) is a progressive, complex, and multifactorial neurodegenerative disorder, still without effective and stable therapeutic strategies. Currently, available medications for AD are based on symptomatic therapy, which include acetylcholinesterase (AChE) inhibitors and N-methyl-D-aspartate (NMDA) receptor antagonist. Additionally, medications such as antipsychotic drugs, antidepressants, sedative, and hypnotic agents, and mood stabilizers are used for the management of behavioral and psychological symptoms of dementia (BPSD). Clinical research has been extensively investigated treatments focusing on the hallmark pathology of AD, including the amyloid deposition, tau hyperphosphorylation, neuroinflammation, and vascular changes; however, so far without success, as all new potential drugs failed to show significant clinical benefit. The underlying heterogeneous etiology and diverse symptoms of AD suggest that a precision medicine strategy is required, which would take into account the complex genetic, epigenetic, and environmental landscape of each AD patient. The article provides a comprehensive overview of the literature on AD, the current and potential therapy of both cognitive symptoms as well as BPSD, with a special focus on gut microbiota and epigenetic modifications as new emerging drug targets. Their specific patterns could represent the basis for novel individually tailored approaches aimed to optimize precision medicine strategies for AD prevention and treatment. However, the successful application of precision medicine to AD demands a further extensive research of underlying pathological processes, as well as clinical and biological complexity of this multifactorial neurodegenerative disorder.

Novel pyridine-containing sultones: Structure-activity relationship and biological evaluation as selective AChE inhibitors for the treatment of Alzheimer's disease

Novel pyridine-containing sultones were synthesized and evaluated for their cholinesterase (ChE) inhibitory activity. Most of compounds showed selective acetylcholinesterase (AChE) inhibitory activity. The structure-activity relationship (SAR) showed: (i) the fused pyridine-containing sultones increase AChE inhibition, series B>series A; (ii) for series A, the effect of the 4-substituent on AChE activity, p->m- or o-; (iii) for series B, a halophenyl group increase activity. Compound B4 (4-(4-chlorophenyl)-2,2-dioxide-3,4,5,6-tetrahydro-1,2-oxathiino[5,6-h]quinoline) was identified as a selective AChE inhibitor (IC₅₀ =8.93 μM), and molecular docking studies revealed a good fit into TcAChE via hydrogen interactions between the δ-pyridylsultone scaffold with Asp72, Ser122, Phe288, Phe290 and Trp84. Compound B4 showed reversible and non-competitive (K_i =7.67 μM) AChE inhibition, nontoxicity and neuroprotective activity. In vivo studies confirmed that compound B4 could ameliorate the cognitive performance of scopolamine-treated C57BL/6 J mice, suggesting a significant benefit of AChE inhibition for a disease-modifying treatment of AD.

QbD-steered development of mixed nanomicelles of galantamine: Demonstration of enhanced brain uptake, prolonged systemic retention and improved biopharmaceutical attributes

PURPOSE

Numerous oral treatment options have been reported for neurological disorders, especially Alzheimer's disease (AD). Galantamine (GAL) is one of such drugs duly approved for management of AD. However, it exhibits poor brain penetration, low intestinal permeation and requires frequent dosing in AD treatment. The present studies, accordingly, were undertaken to develop DSPE-PEG 2000-based micelles loaded with GAL for efficient brain uptake, improved and extended pharmacokinetics, along with reduced dosing regimen.

METHODS

Mixed nanomicelles (MNMs) were systematically formulated using QbD approach, and characterized for morphology, entrapment efficiency andin vitrodrug release.

RESULTS

Studies on CaCo-2 and neuronal U-87 cell lines exhibited substantial enhancement in the cellular permeability and uptake of the developed MNMs. Pharmacokinetic studies performed on rats showed significantly improved values of plasma AUC (i.e., 2.28-fold, p < 0.001), ostensibly due to bypassing of hepatic first-pass metabolism and improved intestinal permeability, together with significant rise in MRT (2.08-fold, p < 0.001) and t_max (4.80-fold; p < 0.001) values, indicating immense potential for prolonged drug residence in body.Besides, substantial elevation in brain drug levels, distinctly improved levels of biochemical parameters in brain homogenates and cognitive improvement in β-amyloid-treated rats, testify the superiority in MNMs in therapeutic management of AD.

CONCLUSIONS

The preclinical findings of the developed nanocarrier systems successfully demonstrate the notable potential of enhanced drug efficacy, extended duration of action and improved patient compliance.