Anti-Neurodegenerative Benefits of Acetylcholinesterase Inhibitors in Alzheimer's Disease: Nexus of Cholinergic and Nerve Growth Factor Dysfunction

Novel benzene sulfonamides with acetylcholinesterase and carbonic anhydrase inhibitory actions

A series of benzene sulfonamides 15-26 were synthesized and determined for their in vitro and in silico inhibitory profiles toward acetylcholinesterase (AChE) and carbonic anhydrases (CAs). Commercially available 3,4-dimethoxytoluene was reacted with chlorosulfonic acid to furnish benzene sulfonyl chloride derivatives. The reaction of substituted benzene sulfonyl chloride with some amines also including (±)-α-amino acid methyl esters afforded a series of novel benzene sulfonamides. In this study, the enzyme inhibition abilities of these compounds were evaluated against AChE and CAs. They exhibited a highly potent inhibition ability on AChE and -CAs (Ki values are in the range of 28.11 ± 4.55 nM and 145.52 ± 28.68 nM for AChE, 39.20 ± 2.10 nM to 131.54 ± 12.82 nM for CA I, and 50.96 ± 9.83 nM and 147.94 ± 18.75 nM for CA II). The present newly synthesized novel benzene sulfonamides displayed efficient inhibitory profiles against AChE and CAs, and it is anticipated that they may emerge as lead molecules for some diseases including glaucoma, epilepsy, and Alzheimer's disease.

Musical hallucinations, secondary delusions, and lack of insight: results from a cohort study

Introduction

Although musical hallucinations do not tend to be accompanied by delusions, occasionally patients persistently accuse others of being responsible for causing the music they perceive, sometimes with severe social consequences such as frequently calling the police or moving house. In this study we seek to broaden our understanding of this rare type of musical hallucination that comes with secondary delusions and lack of insight, and to explore associations, underlying mechanisms, and treatment possibilities.

Methods

The present study is part of a cohort study on musical hallucinations carried out in the Netherlands from 2010 through 2023. Participants underwent testing with the aid of the MuHa Questionnaire, Launay-Slade Hallucinations Scale (LSHS), Schizotypal Personality Questionnaire (SPQ), Hamilton Depression Rating Scale (HDRS), and Mini Mental State Examination (MMSE). Additionally, they underwent a brain MRI, electroencephalogram, and audiological testing.

Results

Five patients out of a group of N = 81 (6%) lacked insight and presented with secondary delusions regarding the perceived music. They were all female, of advanced age, and hearing-impaired, and were diagnosed with cognitive impairment. In three patients (60%), risperidone was started. This had a positive effect on the hallucinations and secondary delusions.

Conclusion

The pathophysiological process underlying musical hallucinations is multifactorial in nature. We consider cognitive impairment the most likely contributing factor of the secondary delusions and lack of insight encountered in our patients, and antipsychotics the most beneficial treatment. On the basis of these small numbers, no definite conclusions can be drawn, so further research is needed to elucidate the underlying mechanisms and to develop evidence-based treatment methods for people experiencing this rare and debilitating combination of symptoms. Since the black box warning of risperidone cautions against the use of this drug in elderly persons with dementia, a proper comparison with the efficacy and safety of other antipsychotics for this group is paramount.

The regulatory effects of fucoidan and laminarin on functional dyspepsia mice induced by loperamide

Gastrointestinal dysmotility is a common cause of functional dyspepsia. As two kinds of polysaccharides derived from brown algae, fucoidan and laminarin possess many physiological properties; however, their relative abilities in regulating gastrointestinal motility have not been illustrated yet. In this study, we aimed to investigate the regulatory effect of fucoidan and laminarin on functional dyspepsia mice induced by loperamide. Mice with gastrointestinal dysmotility were treated with fucoidan (100 and 200 mg per kg bw) and laminarin (50 and 100 mg per kg bw). As a result, fucoidan and laminarin reversed the dysfunction mainly through regulating gastrointestinal hormones (motilin and ghrelin), the cholinergic pathway, the total bile acid level, c-kit protein expression, and gastric smooth muscle contraction-related gene expression (ANO1 and RYR3). Moreover, fucoidan and laminarin intervention modulated the gut microbiota profile including the altered richness of Muribaculaceae, Lachnospiraceae, and Streptococcus. The results indicated that fucoidan and laminarin may restore the rhythm of the migrating motor complex and regulate gut microecology. In conclusion, we provided evidence to support that fucoidan and laminarin might have potential abilities to regulate gastrointestinal motility.

GlyNAC (Glycine and N-Acetylcysteine) Supplementation in Old Mice Improves Brain Glutathione Deficiency, Oxidative Stress, Glucose Uptake, Mitochondrial Dysfunction, Genomic Damage, Inflammation and Neurotrophic Factors to Reverse Age-Associated Cognitive Decline: Implications for Improving Brain Health in Aging

Cognitive decline frequently occurs with increasing age, but mechanisms contributing to age-associated cognitive decline (ACD) are not well understood and solutions are lacking. Understanding and reversing mechanisms contributing to ACD are important because increased age is identified as the single most important risk factor for dementia. We reported earlier that ACD in older humans is associated with glutathione (GSH) deficiency, oxidative stress (OxS), mitochondrial dysfunction, glucose dysmetabolism and inflammation, and that supplementing GlyNAC (glycine and N-acetylcysteine) improved these defects. To test whether these defects occur in the brain in association with ACD, and could be improved/reversed with GlyNAC supplementation, we studied young (20-week) and old (90-week) C57BL/6J mice. Old mice received either regular or GlyNAC supplemented diets for 8 weeks, while young mice received the regular diet. Cognition and brain outcomes (GSH, OxS, mitochondrial energetics, autophagy/mitophagy, glucose transporters, inflammation, genomic damage and neurotrophic factors) were measured. Compared to young mice, the old-control mice had significant cognitive impairment and multiple brain defects. GlyNAC supplementation improved/corrected the brain defects and reversed ACD. This study finds that naturally-occurring ACD is associated with multiple abnormalities in the brain, and provides proof-of-concept that GlyNAC supplementation corrects these defects and improves cognitive function in aging.

Neuro-Nutraceutical Polyphenols: How Far Are We?

The brain, composed of billions of neurons, is a complex network of interacting dynamical systems controlling all body functions. Neurons are the building blocks of the nervous system and their impairment of their functions could result in neurodegenerative disorders. Accumulating evidence shows an increase of brain-affecting disorders, still today characterized by poor therapeutic options. There is a strong urgency to find new alternative strategies to prevent progressive neuronal loss. Polyphenols, a wide family of plant compounds with an equally wide range of biological activities, are suitable candidates to counteract chronic degenerative disease in the central nervous system. Herein, we will review their role in human healthcare and highlight their: antioxidant activities in reactive oxygen species-producing neurodegenerative pathologies; putative role as anti-acetylcholinesterase inhibitors; and protective activity in Alzheimer’s disease by preventing Aβ aggregation and tau hyperphosphorylation. Moreover, the pathology of these multifactorial diseases is also characterized by metal dyshomeostasis, specifically copper (Cu), zinc (Zn), and iron (Fe), most important for cellular function. In this scenario, polyphenols’ action as natural chelators is also discussed. Furthermore, the critical importance of the role exerted by polyphenols on microbiota is assumed, since there is a growing body of evidence for the role of the intestinal microbiota in the gut–brain axis, giving new opportunities to study molecular mechanisms and to find novel strategies in neurological diseases.

HIF-1 signalling pathway was identified as a potential new pathway for Icariin's treatment against Alzheimer's disease based on preclinical evidence and bioinformatics

Aim: Alzheimer's disease (AD) is a neurodegenerative condition that is characterized by the gradual loss of memory and cognitive function. Icariin, which is a natural chemical isolated from Epimedii herba, has been shown to protect against AD. This research examined the potential mechanisms of Icariin's treatment against AD via a comprehensive review of relevant preclinical studies coupled with network pharmacology. Methods: The PubMed, Web of Science, CNKI, WANFANG, and VIP databases were used to identify the relevant studies. The pharmacological characteristics of Icariin were determined using the SwissADME and TCMSP databases. The overlapping targets of Icariin and AD were then utilized to conduct disease oncology (DO) analysis to identify possible hub targets of Icariin in the treatment of AD. The hub targets were then used for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses, and the interactions of the targets and Icariin were assessed via molecular docking and molecular dynamics simulation (MDS). Results: According to the literature review, Icariin alleviates cognitive impairment by regulating the expression of Aβ1-42, Aβ1-40, BACE1, tau, hyperphosphorylated tau, and inflammatory mediators. DO analysis revealed 35 AD-related hub targets, and the HIF-1 signalling pathway was ranked first according to the KEGG pathway analysis. Icariin effectively docked with the 35 hub targets and HIF-1α, and the dynamic binding of the HIF-1-Icariin complex within 100 ns indicated that Icariin contributed to the stability of HIF-1α. Conclusion: In conclusion, our research used a literature review and network pharmacology methods to identify the HIF-1 signalling pathway as a potential pathway for Icariin's treatment against AD.

Carthamus tinctorius L.: A natural neuroprotective source for anti-Alzheimer's disease drugs

ETHNOPHARMACOLOGICAL RELEVANCE

Alzheimer's disease (AD) is a multicausal neurodegenerative disease clinically characterized by generalized dementia. The pathogenic process of AD not only is progressive and complex but also involves multiple factors and mechanisms, including β-amyloid (Aβ) aggregation, tau protein hyperphosphorylation, oxidative stress, and neuroinflammation. As the first-line treatment for AD, cholinesterase inhibitors can, to a certain extent, relieve AD symptoms and delay AD progression. Nonetheless, the current treatment strategies for AD are far from meeting clinical expectations, and more options for AD treatment should be applied in clinical practice.

AIM OF THE REVIEW

The aim of this review was to investigate published reports of C. tinctorius L. and its active constituents in AD treatment through a literature review.

MATERIALS AND METHODS

Information was retrieved from scientific databases including Web of Science, ScienceDirect, Scopus, Google Scholar, Chemical Abstracts Services and books, PubMed, dissertations and technical reports. Keywords used for the search engines were "Honghua" or "Carthamus tinctorius L." or "safflower" in conjunction with "(native weeds OR alien invasive)"AND "Chinese herbal medicine".

RESULTS

A total of 47 literatures about C. tinctorius L. and its active constituents in AD treatment through signaling pathways, immune cells, and disease-related mediators and systematically elucidates potential mechanisms from the point of anti-Aβ aggregation, suppressing tau protein hyperphosphorylation, increasing cholinergic neurotransmitters levels, inhibiting oxidative stress, anti-neuroinflammation, ameliorating synaptic plasticity, and anti-apoptosis.

CONCLUSIONS

Chinese herbal medicine (CHM) is a treasure endowed by nature to mankind. Emerging studies have confirmed that CHM and its active constituents play a positive role in AD treatment. Carthamus tinctorius L., the most commonly used CHM, can be used with medicine and food, with the effect of activating blood circulation and eliminating blood stasis. In the paper, we have concluded that the existing therapeutic mechanisms of C. tinctorius L. and summarized the potential mechanisms of C. tinctorius L. and its active constituents in AD treatment through a literature review.

Amyloid β, Lipid Metabolism, Basal Cholinergic System, and Therapeutics in Alzheimer’s Disease

The presence of insoluble aggregates of amyloid β (Aβ) in the form of neuritic plaques (NPs) is one of the main features that define Alzheimer’s disease. Studies have suggested that the accumulation of these peptides in the brain significantly contributes to extensive neuronal loss. Furthermore, the content and distribution of cholesterol in the membrane have been shown to have an important effect on the production and subsequent accumulation of Aβ peptides in the plasma membrane, contributing to dysfunction and neuronal death. The monomeric forms of these membrane-bound peptides undergo several conformational changes, ranging from oligomeric forms to beta-sheet structures, each presenting different levels of toxicity. Aβ peptides can be internalized by particular receptors and trigger changes from Tau phosphorylation to alterations in cognitive function, through dysfunction of the cholinergic system. The goal of this review is to summarize the current knowledge on the role of lipids in Alzheimer’s disease and their relationship with the basal cholinergic system, as well as potential disease-modifying therapies.

Current Progress on Neuroprotection Induced by Artemisia, Ginseng, Astragalus, and Ginkgo Traditional Chinese Medicines for the Therapy of Alzheimer's Disease

Aging is associated with the occurrence of diverse degenerative changes in various tissues and organs and with an increased incidence of neurological disorders, especially neurodegenerative diseases such as Alzheimer's disease (AD). In recent years, the search for effective components derived from medicinal plants in delaying aging and preventing and treating neurodegenerative diseases has been increasing and the number of related publications shows a rising trend. Here, we present a concise, updated review on the preclinical and clinical research progress in the assessment of the therapeutic potential of different traditional Chinese medicines and derived active ingredients and their effect on the signaling pathways involved in AD neuroprotection. Recognized by their multitargeting ability, these natural compounds hold great potential in developing novel drugs for AD.