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1.
Alzheimers Dement ; 20(4): 2731-2741, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38411315

RESUMO

INTRODUCTION: Alzheimer's disease (AD) involves the complement cascade, with complement component 3 (C3) playing a key role. However, the relationship between C3 and amyloid beta (Aß) in blood is limited. METHODS: Plasma C3 and Aß oligomerization tendency (AßOt) were measured in 35 AD patients and 62 healthy controls. Correlations with cerebrospinal fluid (CSF) biomarkers, cognitive impairment, and amyloid positron emission tomography (PET) were analyzed. Differences between biomarkers were compared in groups classified by concordances of biomarkers. RESULTS: Plasma C3 and AßOt were elevated in AD patients and in CSF or amyloid PET-positive groups. Weak positive correlation was found between C3 and AßOt, while both had strong negative correlations with CSF Aß42 and cognitive performance. Abnormalities were observed for AßOt and CSF Aß42 followed by C3 changes. DISCUSSION: Increased plasma C3 in AD are associated with amyloid pathology, possibly reflecting a defense response for Aß clearance. Further studies on Aß-binding proteins will enhance understanding of Aß mechanisms in blood.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/líquido cefalorraquidiano , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano , Complemento C3 , Amiloide , Tomografia por Emissão de Pósitrons/métodos , Biomarcadores/líquido cefalorraquidiano , Fragmentos de Peptídeos/líquido cefalorraquidiano
2.
Front Aging Neurosci ; 16: 1332455, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38384937

RESUMO

Introduction: Parkinson's disease (PD) is a neurodegenerative disorder characterized by dopaminergic dysfunction and associated with abnormalities in the cholinergic system. However, the relationship between PD and cholinergic dysfunction, particularly in exosomes, is not fully understood. Methods: We enrolled 37 patients with PD and 44 healthy controls (HC) to investigate acetylcholinesterase (AChE) activity in CD9-positive and L1CAM-positive exosomes. Exosomes were isolated from plasma using antibody-coupled magnetic beads, and their sizes and concentrations were assessed using transmission electron microscopy, nanoparticle tracking analysis, and western blotting. Subsequently, the AChE activity in these exosomes was analyzed in relation to various clinical parameters. Results: A significant decrease in AChE activity was observed in CD9-positive exosomes derived from patients with PD, whereas no significant differences were found in L1CAM-positive exosomes. Further analysis with a larger sample size confirmed a substantial reduction in AChE activity in CD9-positive exosomes from the PD plasma, with moderate diagnostic accuracy. The decrease in AChE activity of CD9-positive exosomes did not show an association with cognitive impairment but displayed a trend toward correlation with PD progression. Discussion: The reduction in AChE activity in CD9-positive exosomes suggests potential peripheral cholinergic dysfunction in PD, independent of the central cholinergic system. The observed alterations in AChE activity provide valuable insights into the association between cholinergic dysfunction and the pathogenesis of PD.

3.
Int J Mol Sci ; 24(20)2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37895139

RESUMO

In this manuscript, we introduced a French EOAD patient in Korea who carried the presenilin-1 (PSEN1) Glu318Gly mutations with four possible risk variants, including sortilin-related receptor 1 (SORL1) Glu270Lys, ATP-binding cassette subfamily A member 7 (ABCA7) Val1946Met, translocase of outer mitochondrial membrane 40 (TOMM40) Arg239Trp, and granulin (GRN) Ala505Gly. The patient started to present memory decline and behavioral dysfunction in his early 60s. His brain imaging presented amyloid deposits by positron emission tomography (PET-CT). The multimer detection system (MDS) screening test for plasma for amyloid oligomers was also positive, which supported the AD diagnosis. It was verified that PSEN1 Glu318Gly itself may not impact amyloid production. However, additional variants were found in other AD and non-AD risk genes, as follows: SORL1 Glu270Lys was suggested as a risk mutation for AD and could increase amyloid peptide production and impair endosome functions. ABCA7 Val1946Met was a novel variant that was predicted to be damaging. The GRN Ala505Gly was a variant with uncertain significance; however, it may reduce the granulin levels in the plasma of dementia patients. Pathway analysis revealed that PSEN1 Glu318Gly may work as a risk factor along with the SORL1 and ABCA7 variants since pathway analysis revealed that PSEN1 could directly interact with them through amyloid-related and lipid metabolism pathways. TOMM40 and PSEN1 could have common mechanisms through mitochondrial dysfunction. It may be possible that PSEN1 Glu318Gly and GRN Ala505Gly would impact disease by impairing immune-related pathways, including microglia and astrocyte development, or NFkB-related pathways. Taken together, the five risk factors may contribute to disease-related pathways, including amyloid and lipid metabolism, or impair immune mechanisms.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Proteínas Amiloidogênicas/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Granulinas/metabolismo , Proteínas Relacionadas a Receptor de LDL/metabolismo , Proteínas de Membrana Transportadoras/genética , Mutação , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Presenilina-1/genética , Presenilina-1/metabolismo , Masculino , Pessoa de Meia-Idade
4.
Cells ; 12(20)2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37887303

RESUMO

A form of dementia distinct from healthy cognitive aging, Alzheimer's disease (AD) is a complex multi-stage disease that currently afflicts over 50 million people worldwide. Unfortunately, previous therapeutic strategies developed from murine models emulating different aspects of AD pathogenesis were limited. Consequently, researchers are now developing models that express several aspects of pathogenesis that better reflect the clinical situation in humans. As such, this review seeks to provide insight regarding current applications of mammalian models in AD research by addressing recent developments and characterizations of prominent transgenic models and their contributions to pathogenesis as well as discuss the advantages, limitations, and application of emerging models that better capture genetic heterogeneity and mixed pathologies observed in the clinical situation.


Assuntos
Doença de Alzheimer , Animais , Camundongos , Doença de Alzheimer/patologia , Nível de Saúde , Mamíferos , Inquéritos e Questionários , Proteínas tau/genética
5.
Cells ; 12(15)2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37566027

RESUMO

Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease affecting the upper and lower motor neurons, leading to muscle weakness, motor impairments, disabilities and death. Approximately 5-10% of ALS cases are associated with positive family history (familial ALS or fALS), whilst the remainder are sporadic (sporadic ALS, sALS). At least 50 genes have been identified as causative or risk factors for ALS. Established pathogenic variants include superoxide dismutase type 1 (SOD1), chromosome 9 open reading frame 72 (c9orf72), TAR DNA Binding Protein (TARDBP), and Fused In Sarcoma (FUS); additional ALS-related genes including Charged Multivesicular Body Protein 2B (CHMP2B), Senataxin (SETX), Sequestosome 1 (SQSTM1), TANK Binding Kinase 1 (TBK1) and NIMA Related Kinase 1 (NEK1), have been identified. Mutations in these genes could impair different mechanisms, including vesicle transport, autophagy, and cytoskeletal or mitochondrial functions. So far, there is no effective therapy against ALS. Thus, early diagnosis and disease risk predictions remain one of the best options against ALS symptomologies. Proteomic biomarkers, microRNAs, and extracellular vehicles (EVs) serve as promising tools for disease diagnosis or progression assessment. These markers are relatively easy to obtain from blood or cerebrospinal fluids and can be used to identify potential genetic causative and risk factors even in the preclinical stage before symptoms appear. In addition, antisense oligonucleotides and RNA gene therapies have successfully been employed against other diseases, such as childhood-onset spinal muscular atrophy (SMA), which could also give hope to ALS patients. Therefore, an effective gene and biomarker panel should be generated for potentially "at risk" individuals to provide timely interventions and better treatment outcomes for ALS patients as soon as possible.


Assuntos
Esclerose Amiotrófica Lateral , Doenças Neurodegenerativas , Humanos , Criança , Esclerose Amiotrófica Lateral/genética , Esclerose Amiotrófica Lateral/terapia , Esclerose Amiotrófica Lateral/metabolismo , Proteômica , Proteínas de Ligação a DNA/metabolismo , Superóxido Dismutase-1 , Biomarcadores , Fatores de Risco , DNA Helicases , RNA Helicases , Enzimas Multifuncionais
7.
Alzheimers Dement ; 19(9): 4020-4027, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37200243

RESUMO

INTRODUCTION: Semantic dementia (SD) is a progressive neurodegenerative disease associated with impaired vocabulary that progresses to memory impairment. Post-mortem immunohistochemical analysis is the current reliable method of differentiating TDP-43 deposits in cortical tissue; no means of antemortem diagnosis exists in biofluids, let alone in plasma. METHODS: Here the multimer detection system (MDS) was used to quantify the oligomeric TDP-43 (o-TDP-43) concentrations in plasma of Korean SD patients (n = 16, 6 male, 10 female, ages 59-87). The o-TDP-43 concentrations were compared with the total TDP-43 (t-TDP-43) concentrations quantified through conventional enzyme-linked immunosorbent assay (ELISA). RESULTS AND DISCUSSION: Only MDS showed a significant increase in o-TDP-43 concentrations in the plasma of patients with SD compared to other neurodegenerative disorders and normal controls (p < 0.05). Based on these results, o-TDP-43 concentrations through the application of MDS may be a useful plasma biomarker in SD-FTD (frontotemporal dementia) diagnosis.


Assuntos
Demência Frontotemporal , Doenças Neurodegenerativas , Humanos , Masculino , Feminino , Doenças Neurodegenerativas/complicações , Proteínas de Ligação a DNA , República da Coreia
8.
Dement Neurocogn Disord ; 22(2): 84, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37179690

RESUMO

[This corrects the article on p. 41 in vol. 17, PMID: 30906391.].

9.
Int J Mol Sci ; 24(9)2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37175851

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease that causes a gradual loss of normal motor and cognitive function. The complex AD pathophysiology involves various factors such as oxidative stress, neuroinflammation, amyloid-beta (Aß) aggregation, disturbed neurotransmission, and apoptosis. The available drugs suffer from a range of side effects and are not able to cover different aspects of the disease. Therefore, finding a safer therapeutic approach that can affect multiple targets at a time is highly desirable. In the present study, the underlying neuroprotective mechanism of an important culinary spice, Syzygium aromaticum (Clove) extract, and major bioactive compounds were studied in hydrogen peroxide-induced oxidative stress in human neuroblastoma SH-SY5Y cell lines as a model. The extracts were subjected to GC-MS to identify important bioactive components. The extracts and key bio-actives reduced reactive oxygen species (ROS), restored mitochondrial membrane potential (MMP), and provided neuroprotection from H2O2-induced oxidative stress in cell-based assays due to the antioxidant action. They also reduced lipid peroxidation significantly and restored GSH content. Clove extracts have also displayed anti-acetylcholinesterase (AChE) activity, anti-glycation potential, and Aß aggregation/fibrilization inhibition. The multitarget neuroprotective approach displayed by Clove makes it a potential candidate for AD drug development.


Assuntos
Doença de Alzheimer , Neuroblastoma , Doenças Neurodegenerativas , Fármacos Neuroprotetores , Syzygium , Humanos , Fármacos Neuroprotetores/farmacologia , Syzygium/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Extratos Vegetais/farmacologia , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo
10.
Int J Mol Sci ; 24(9)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37176125

RESUMO

Presenilin 1 (PSEN1) is a part of the gamma secretase complex with several interacting substrates, including amyloid precursor protein (APP), Notch, adhesion proteins and beta catenin. PSEN1 has been extensively studied in neurodegeneration, and more than 300 PSEN1 mutations have been discovered to date. In addition to the classical early onset Alzheimer's disease (EOAD) phenotypes, PSEN1 mutations were discovered in several atypical AD or non-AD phenotypes, such as frontotemporal dementia (FTD), Parkinson's disease (PD), dementia with Lewy bodies (DLB) or spastic paraparesis (SP). For example, Leu113Pro, Leu226Phe, Met233Leu and an Arg352 duplication were discovered in patients with FTD, while Pro436Gln, Arg278Gln and Pro284Leu mutations were also reported in patients with motor dysfunctions. Interestingly, PSEN1 mutations may also impact non-neurodegenerative phenotypes, including PSEN1 Pro242fs, which could cause acne inversa, while Asp333Gly was reported in a family with dilated cardiomyopathy. The phenotypic diversity suggests that PSEN1 may be responsible for atypical disease phenotypes or types of disease other than AD. Taken together, neurodegenerative diseases such as AD, PD, DLB and FTD may share several common hallmarks (cognitive and motor impairment, associated with abnormal protein aggregates). These findings suggested that PSEN1 may interact with risk modifiers, which may result in alternative disease phenotypes such as DLB or FTD phenotypes, or through less-dominant amyloid pathways. Next-generation sequencing and/or biomarker analysis may be essential in clearly differentiating the possible disease phenotypes and pathways associated with non-AD phenotypes.


Assuntos
Doença de Alzheimer , Demência Frontotemporal , Doença de Parkinson , Doença de Pick , Humanos , Doença de Alzheimer/genética , Presenilina-1/genética , Demência Frontotemporal/genética , Precursor de Proteína beta-Amiloide/genética , Mutação , Fenótipo , Doença de Parkinson/genética , Presenilina-2/genética
11.
Antioxidants (Basel) ; 12(5)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37237954

RESUMO

Neurodegenerative diseases (NDs) are a family of disorders that cause progressive structural and functional degeneration of neurons. Among all the organs in the body, the brain is the one that is the most affected by the production and accumulation of ROS. Various studies have shown that an increase in oxidative stress is a common pathophysiology for almost all NDs, which further affects various other pathways. The available drugs lack the wide spectrum necessary to confront these complexities altogether. Hence, a safe therapeutic approach to target multiple pathways is highly desirable. In the present study, the hexane and ethyl acetate extracts of Piper nigrum (black pepper), an important spice, were evaluated for their neuroprotective potential in hydrogen peroxide-induced oxidative stress in human neuroblastoma cells (SH-SY5Y). The extracts were also subjected to GC/MS to identify the important bioactives present. The extracts exhibited neuroprotection by significantly decreasing the oxidative stress and restoring the mitochondrial membrane potential in the cells. Additionally, the extracts displayed potent anti-glycation and significant anti-Aß fibrilization activities. The extracts were competitive inhibitors of AChE. The multitarget neuroprotective mechanism displayed by Piper nigrum indicates it as a potential candidate in the treatment of NDs.

12.
Int J Mol Sci ; 24(8)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37108607

RESUMO

The etiology of early-onset Alzheimer's disease (EOAD) is associated with alterations in the production of amyloid beta (Aß) species caused by mutations in the APP, PSEN1, and PSEN2 genes. Mutations affect intra- or inter-molecular interactions and processes between the γ-secretase complex and amyloid precursor protein (APP), leading to the aberrant sequential cleavage of Aß species. A 64-year-old woman presented with progressive memory decline, mild right hippocampal atrophy, and a family history of Alzheimer's dementia (AD). Whole exome sequencing was performed to evaluate AD-related gene mutations, which were verified by Sanger sequencing. A mutation-caused structural alteration of APP was predicted using in silico prediction programs. Two AD-related mutations, in APP (rs761339914; c.G1651A; p.V551M) and PSEN2 (rs533813519; c.C505A; p.H169N), were identified. The APP Val551Met mutation in the E2 domain may influence APP homodimerization through changes in intramolecular interactions between adjacent amino acids, altering Aß production. The second mutation was PSEN2 His169Asn mutation, which was previously reported in five EOAD patients from Korea and China, with a relatively high frequency in the East Asian population. According to a previous report, the presenilin 2 protein was predicted to result in a major helical torsion by PSEN2 His169Asn mutation. Notably, the co-existence of APP Val551Met and PSEN2 His169Asn may induce a synergistic effect by both mutations. Future functional studies are needed to clarify the pathological effects of these double mutations.


Assuntos
Doença de Alzheimer , Feminino , Humanos , Pessoa de Meia-Idade , Doença de Alzheimer/genética , Doença de Alzheimer/epidemiologia , Precursor de Proteína beta-Amiloide/genética , Peptídeos beta-Amiloides/genética , Presenilina-2/genética , Mutação , Presenilina-1/genética , República da Coreia
13.
Nutrients ; 16(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38201932

RESUMO

Cordyceps, also known as "zombie fungus", is a non-poisonous mushroom that parasitizes insects for growth and development by manipulating the host system in a way that makes the victim behave like a "zombie". These species produce promising bioactive metabolites, like adenosine, ß-glucans, cordycepin, and ergosterol. Cordyceps has been used in traditional medicine due to its immense health benefits, as it boosts stamina, appetite, immunity, longevity, libido, memory, and sleep. Neuronal loss is the typical feature of neurodegenerative diseases (NDs) (Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS)) and neurotrauma. Both these conditions share common pathophysiological features, like oxidative stress, neuroinflammation, and glutamatergic excitotoxicity. Cordyceps bioactives (adenosine, N6-(2-hydroxyethyl)-adenosine, ergosta-7, 9 (11), 22-trien-3ß-ol, active peptides, and polysaccharides) exert potential antioxidant, anti-inflammatory, and anti-apoptotic activities and display beneficial effects in the management and/or treatment of neurodegenerative disorders in vitro and in vivo. Although a considerable list of compounds is available from Cordyceps, only a few have been evaluated for their neuroprotective potential and still lack information for clinical trials. In this review, the neuroprotective mechanisms and safety profile of Cordyceps extracts/bioactives have been discussed, which might be helpful in the identification of novel potential therapeutic entities in the future.


Assuntos
Agaricales , Cordyceps , Fármacos Neuroprotetores , Fármacos Neuroprotetores/farmacologia , Neuroproteção , Adenosina
14.
Int J Mol Sci ; 25(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38203287

RESUMO

A pathogenic mutation in presenilin-1 (PSEN1), His214Asn, was found in a male patient with memory decline at the age of 41 in Korea for the first time. The proband patient was associated with a positive family history from his father, paternal aunt, and paternal grandmother without genetic testing. He was diagnosed with early onset Alzheimer's disease (EOAD). PSEN1 His214Asn was initially reported in an Italian family, where the patient developed phenotypes similar to the current proband patient. Magnetic resonance imaging (MRI) scans revealed a mild hippocampal atrophy. The amyloid positron emission tomography (amyloid-PET) was positive, along with the positive test results of the increased amyloid ß (Aß) oligomerization tendency with blood. The PSEN1 His214 amino acid position plays a significant role in the gamma-secretase function, especially from three additional reported mutations in this residue: His214Asp, His214Tyr, and His214Arg. The structure prediction model revealed that PSEN1 protein His214 may interact with Trp215 of His-Trp cation-π interaction, and the mutations of His214 would destroy this interaction. The His-Trp cation-π interaction between His214 and Trp215 would play a crucial structural role in stabilizing the 4th transmembrane domain of PSEN1 protein, especially when aromatic residues were often reported in the membrane interface of the lipid-extracellular region of alpha helices or beta sheets. The His214Asn would alter the cleavage dynamics of gamma-secretase from the disappeared interactions between His214 and Trp215 inside of the helix, resulting in elevated amyloid production. Hence, the increased Aß was reflected in the increased Aß oligomerization tendency and the accumulations of Aß in the brain from amyloid-PET, leading to EOAD.


Assuntos
Doença de Alzheimer , Histidina , Humanos , Masculino , Histidina/genética , Triptofano , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Presenilina-1/genética , Secretases da Proteína Precursora do Amiloide , Mutação , Proteínas Amiloidogênicas , Cátions , República da Coreia
15.
Antioxidants (Basel) ; 13(1)2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38275629

RESUMO

Neurodegenerative diseases (NDs) are a large category of progressive neurological disorders with diverse clinical and pathological characteristics. Among the NDs, Alzheimer's disease (AD) is the most widespread disease, which affects more than 400 million people globally. Oxidative stress is evident in the pathophysiology of nearly all NDs by affecting several pathways in neurodegeneration. No single drug can manage multi-faceted diseases like NDs. Therefore, an alternative therapeutic strategy is required, which can affect several pathophysiological pathways at a time. To achieve this aim, hexane and ethyl acetate extract from Trachyspermum ammi (Carom) were prepared, and GC/MS identified the bioactive compounds. For the cell-based assays, oxidative stress was induced in SH-SY5Y neuroblastoma cells using hydrogen peroxide to evaluate the neuroprotective potential of the Carom extracts/bioactives. The extracts/bioactives provided neuroprotection in the cells by modulating multiple pathways involved in neurodegeneration, such as alleviating oxidative stress and mitochondrial membrane potential. They were potent inhibitors of acetylcholine esterase enzymes and displayed competitive/mixed-type inhibition. Additionally, anti-Aß1-42 fibrilization/oligomerization and anti-glycation activities were also analyzed. The multi-faceted neuroprotection shown via Carom/Carvacrol makes it a prospective contender in drug development for NDs.

16.
Int J Mol Sci ; 23(24)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36555832

RESUMO

Amyloid precursor protein (APP), presenilin 1 (PSEN1), and presenilin 2 (PSEN2) are associated with autosomal-dominant early-onset Alzheimer's disease (AD). Most mutations have been identified in the PSEN1 gene. We discovered a PSEN1 mutation (Tyr389His) in a Korean patient with early-onset AD who presented memory decline at 41 years of age followed by language, memory, and visuospatial dysfunctions. As this is the third such patient identified in Korea, this mutation may be involved in AD pathogenesis, suggesting that routine screening is necessary in this population. Altered intra-molecular interactions with the mutated amino acid may result in the destabilization of γ-secretase. In the future, a panel incorporating genes with relatively high-frequency rare variants, along with the APOE4 gene, may predict the onset of AD and facilitate customized treatment.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/genética , Mutação , Presenilina-1/genética , Presenilina-1/química , Presenilina-2/genética , República da Coreia
17.
Alzheimers Res Ther ; 14(1): 201, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36587215

RESUMO

BACKGROUND: Alpha-synuclein (α-syn) is considered the main pathophysiological protein component of Lewy bodies in synucleinopathies. α-Syn is an intrinsically disordered protein (IDP), and several types of structural conformations have been reported, depending on environmental factors. Since IDPs may have distinctive functions depending on their structures, α-syn can play different roles and interact with several proteins, including amyloid-beta (Aß) and tau, in Alzheimer's disease (AD) and other neurodegenerative disorders. MAIN BODY: In previous studies, α-syn aggregates in AD brains suggested a close relationship between AD and α-syn. In addition, α-syn directly interacts with Aß and tau, promoting mutual aggregation and exacerbating the cognitive decline. The interaction of α-syn with Aß and tau presented different consequences depending on the structural forms of the proteins. In AD, α-syn and tau levels in CSF were both elevated and revealed a high positive correlation. Especially, the CSF α-syn concentration was significantly elevated in the early stages of AD. Therefore, it could be a diagnostic marker of AD and help distinguish AD from other neurodegenerative disorders by incorporating other biomarkers. CONCLUSION: The overall physiological and pathophysiological functions, structures, and genetics of α-syn in AD are reviewed and summarized. The numerous associations of α-syn with Aß and tau suggested the significance of α-syn, as a partner of the pathophysiological roles in AD. Understanding the involvements of α-syn in the pathology of Aß and tau could help address the unresolved issues of AD. In particular, the current status of the CSF α-syn in AD recommends it as an additional biomarker in the panel for AD diagnosis.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/patologia , alfa-Sinucleína/metabolismo , Proteínas tau/metabolismo , Peptídeos beta-Amiloides , Biomarcadores
18.
Prion ; 16(1): 265-294, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36515657

RESUMO

Prion diseases are a group of incurable zoonotic neurodegenerative diseases (NDDs) in humans and other animals caused by the prion proteins. The abnormal folding and aggregation of the soluble cellular prion proteins (PrPC) into scrapie isoform (PrPSc) in the Central nervous system (CNS) resulted in brain damage and other neurological symptoms. Different therapeutic approaches, including stalling PrPC to PrPSc conversion, increasing PrPSc removal, and PrPC stabilization, for which a spectrum of compounds, ranging from organic compounds to antibodies, have been explored. Additionally, a non-PrP targeted drug strategy using serpin inhibitors has been discussed. Despite numerous scaffolds being screened for anti-prion activity in vitro, only a few were effective in vivo and unfortunately, almost none of them proved effective in the clinical studies, most likely due to toxicity and lack of permeability. Recently, encouraging results from a prion-protein monoclonal antibody, PRN100, were presented in the first human trial on CJD patients, which gives a hope for better future for the discovery of other new molecules to treat prion diseases. In this comprehensive review, we have re-visited the history and discussed various classes of anti-prion agents, their structure, mode of action, and toxicity. Understanding pathogenesis would be vital for developing future treatments for prion diseases. Based on the outcomes of existing therapies, new anti-prion agents could be identified/synthesized/designed with reduced toxicity and increased bioavailability, which could probably be effective in treating prion diseases.


Assuntos
Doenças Priônicas , Príons , Scrapie , Animais , Ovinos , Humanos , Príons/química , Proteínas Priônicas , Doenças Priônicas/tratamento farmacológico , Doenças Priônicas/diagnóstico
19.
Int J Mol Sci ; 23(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36362122

RESUMO

Presenilin-2 (PSEN2) mutation Thr421Met was identified from a 57-years old patient with early onset Alzheimer's disease (EOAD) for the first time in Korea. Previously, this mutation was discovered in an EOAD patient in Japan without a change on amyloid production from the cellular study. Both Korean and Japanese patients developed the disease in their 50s. Memory loss was prominent in both cases, but no additional clinical information was available on the Japanese patient. Magnetic resonance imaging (MRI) images of the Korean patient revealed asymmetric atrophies in both temporo-parietal lobes. In addition, amyloid positron emission tomography (PET) also revealed amyloid deposits in the gray matter of the temporo-parietal lobes asymmetrically. PSEN2 Thr421 was conserved among a majority of vertebrates (such as zebras, elephants, and giant pandas); hence, Thr421 could play an important role in its functions and any mutations could cause detrimental ramifications in its interactions. Interestingly, PSEN2 Thr421 could have homology with PSEN1 Thr440, as PSEN1 T440del mutations were reported from patients with AD or dementia with Lewy bodies. Hence, the changed amino acid from threonine to methionine of PSEN2 Thr421 could cause significant structural alterations in causing local protein dynamics, leading to its pathogenicity in EOAD. Lastly, PSEN2 Thr421Met may interact with other mutations in neurodegenerative disease related genes, which were found in the proband patient, such as ATP binding cassette subfamily A member 7 (ABCA7), Notch Receptor 3 (NOTCH3), or Leucine-rich repeat kinase 2 (LRRK2). These interactions of pathway networks among PSEN2 and other disease risk factors could be responsible for the disease phenotype through other pathways. For example, PSEN2 and ABCA7 may impact amyloid processing and reduce amyloid clearance. Interaction between PSEN2 and NOTCH3 variants may be associated with abnormal NOTCH signaling and a lower degree of neuroprotection. Along with LRRK2 variants, PSEN2 Thr421Met may impact neurodegeneration through Wnt related pathways. In the future, cellular studies of more than one mutation by CRISPR-Cas9 method along with biomarker profiles could be helpful to understand the complicated pathways.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Humanos , Presenilina-2/genética , Doença de Alzheimer/genética , Mutação , Povo Asiático , Presenilina-1/genética , Precursor de Proteína beta-Amiloide/genética
20.
Nutrients ; 14(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36432418

RESUMO

Ficus religiosa (Bo tree or sacred fig) and Ficus benghalensis (Indian banyan) are of immense spiritual and therapeutic importance. Various parts of these trees have been investigated for their antioxidant, antimicrobial, anticonvulsant, antidiabetic, anti-inflammatory, analgesic, hepatoprotective, dermoprotective, and nephroprotective properties. Previous reviews of Ficus mostly discussed traditional usages, photochemistry, and pharmacological activities, though comprehensive reviews of the neuroprotective potential of these Ficus species extracts and/or their important phytocompounds are lacking. The interesting phytocompounds from these trees include many bengalenosides, carotenoids, flavonoids (leucopelargonidin-3-O-ß-d-glucopyranoside, leucopelargonidin-3-O-α-l-rhamnopyranoside, lupeol, cetyl behenate, and α-amyrin acetate), flavonols (kaempferol, quercetin, myricetin), leucocyanidin, phytosterols (bergapten, bergaptol, lanosterol, ß-sitosterol, stigmasterol), terpenes (α-thujene, α-pinene, ß-pinene, α-terpinene, limonene, ß-ocimene, ß-bourbonene, ß-caryophyllene, α-trans-bergamotene, α-copaene, aromadendrene, α-humulene, alloaromadendrene, germacrene, γ-cadinene, and δ-cadinene), and diverse polyphenols (tannin, wax, saponin, leucoanthocyanin), contributing significantly to their pharmacological effects, ranging from antimicrobial action to neuroprotection. This review presents extensive mechanistic insights into the neuroprotective potential, especially important phytochemicals from F. religiosa and F. benghalensis. Owing to the complex pathophysiology of neurodegenerative disorders (NDDs), the currently existing drugs merely alleviate the symptoms. Hence, bioactive compounds with potent neuroprotective effects through a multitarget approach would be of great interest in developing pharmacophores for the treatment of NDDs.


Assuntos
Ficus , Ficus/química , Árvores , Neuroproteção , Flavonóis , Extratos Vegetais/química
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