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1.
Biochim Biophys Acta Mol Basis Dis ; 1869(7): 166800, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37423141

RESUMO

BACKGROUND & AIMS: Fatty acid translocase CD36 (CD36/FAT) is a widely expressed membrane protein with multiple immuno-metabolic functions. Genetic CD36 deficiency is associated with increased risk of metabolic dysfunction-associated fatty liver disease (MAFLD) in patients. Liver fibrosis severity mainly affects the prognosis in patients with MAFLD, but the role of hepatocyte CD36 in liver fibrosis of MAFLD remains unclear. METHODS: A high-fat high-cholesterol diet and a high-fat diet with high-fructose drinking water were used to induce nonalcoholic steatohepatitis (NASH) in hepatocyte-specific CD36 knockout (CD36LKO) and CD36flox/flox (LWT) mice. Human hepG2 cell line was used to investigate the role of CD36 in regulating Notch pathway in vitro. RESULTS: Compared to LWT mice, CD36LKO mice were susceptible to NASH diet-induced liver injury and fibrosis. The analysis of RNA-sequencing data revealed that Notch pathway was activated in CD36LKO mice. LY3039478, an inhibitor of γ-secretase, inhibited Notch1 protein S3 cleavage and Notch1 intracellular domain (N1ICD) production, alleviating liver injury and fibrosis in CD36LKO mice livers. Likewise, both LY3039478 and knockdown of Notch1 inhibited the CD36KO-induced increase of N1ICD production, causing the decrease of fibrogenic markers in CD36KO HepG2 cells. Mechanistically, CD36 formed a complex with Notch1 and γ-secretase in lipid rafts, and hence CD36 anchored Notch1 in lipid rafts domains and blocked Notch1/γ-secretase interaction, inhibiting γ-secretase-mediated cleavage of Notch1 and the production of N1ICD. CONCLUSIONS: Hepatocyte CD36 plays a key role in protecting mice from diet-induced liver injury and fibrosis, which may provide a potential therapeutic strategy for preventing liver fibrogenesis in MAFLD.


Assuntos
Antígenos CD36 , Dieta , Hepatócitos , Cirrose Hepática , Hepatopatia Gordurosa não Alcoólica , Fragmentos de Peptídeos , Receptor Notch1 , Animais , Camundongos , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Antígenos CD36/deficiência , Antígenos CD36/genética , Antígenos CD36/metabolismo , Dieta/efeitos adversos , Deleção de Genes , Células Hep G2 , Hepatócitos/metabolismo , Cirrose Hepática/etiologia , Cirrose Hepática/genética , Cirrose Hepática/prevenção & controle , Microdomínios da Membrana , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Fenótipo , Receptor Notch1/química , Receptor Notch1/metabolismo , Transdução de Sinais , Humanos
2.
Int J Mol Sci ; 24(14)2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37511086

RESUMO

AD is the most common neurodegenerative disorder characterized by progressive memory impairment and cognitive deficits. The pathology of AD is still unclear; however, several studies have shown that the aggregation of the Aß peptide in the CNS is an exclusively pathological process involved in AD. Currently, there is no proven medication to cure or prevent the disease progression. Nevertheless, various therapeutic approaches for AD show only relief of symptoms and mostly work on cognitive recovery. However, one of the promising approaches for therapeutic intervention is to use inhibitors for blocking the Aß peptide aggregation process. Recently, herbal phenolic compounds have been shown to have a therapeutic property for treatment of AD due to their multifaceted action. In this study, we investigated the effectiveness of SA, Gn Rb1, and DMyr on inhibiting the aggregation and toxicity of Aß40 and Aß42 using different biochemical and cell-based assays. Our results showed that SA and DMyr inhibit Aß40 and Aß42 fibrillation, seeded aggregation, and toxicity. Gn Rb1 did not have any effect on the aggregation or toxicity induced by Aß40 and Aß42. Moreover, SA and DMyr were able to disaggregate the preformed fibrils. Overall, these compounds may be used alone or synergistically and could be considered as a lead for designing new compounds that could be used as effective treatment of AD and related disorders.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Disfunção Cognitiva , Fragmentos de Peptídeos , Humanos , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/metabolismo
4.
Life Sci Alliance ; 5(11)2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35831024

RESUMO

Mitochondria-ER contact sites (MERCs) orchestrate many important cellular functions including regulating mitochondrial quality control through mitophagy and mediating mitochondrial calcium uptake. Here, we identify and functionally characterize the Drosophila ortholog of the recently identified mammalian MERC protein, Pdzd8. We find that reducing pdzd8-mediated MERCs in neurons slows age-associated decline in locomotor activity and increases lifespan in Drosophila. The protective effects of pdzd8 knockdown in neurons correlate with an increase in mitophagy, suggesting that increased mitochondrial turnover may support healthy aging of neurons. In contrast, increasing MERCs by expressing a constitutive, synthetic ER-mitochondria tether disrupts mitochondrial transport and synapse formation, accelerates age-related decline in locomotion, and reduces lifespan. Although depletion of pdzd8 prolongs the survival of flies fed with mitochondrial toxins, it is also sufficient to rescue locomotor defects of a fly model of Alzheimer's disease expressing Amyloid ß42 (Aß42). Together, our results provide the first in vivo evidence that MERCs mediated by the tethering protein pdzd8 play a critical role in the regulation of mitochondrial quality control and neuronal homeostasis.


Assuntos
Peptídeos beta-Amiloides , Proteínas de Drosophila , Drosophila melanogaster , Retículo Endoplasmático , Mitocôndrias , Fragmentos de Peptídeos , Doença de Alzheimer , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/toxicidade , Animais , Senescência Celular , Modelos Animais de Doenças , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/efeitos dos fármacos , Drosophila melanogaster/metabolismo , Drosophila melanogaster/fisiologia , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Técnicas de Silenciamento de Genes , Aptidão Genética , Locomoção/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/efeitos dos fármacos , Mitofagia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/toxicidade
5.
Clin Transl Med ; 12(2): e716, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35184395

RESUMO

BACKGROUND: Immunotransmitters (e.g., neurotransmitters and neuromodulators) could orchestrate diverse immune responses; however, the elaborated mechanism by which melatonergic activation governs inflammation remains less defined. METHODS: Primary macrophages, various cell lines, and Pasteurella multocida (PmCQ2)-infected mice were respectively used to illustrate the influence of melatonergic signalling on inflammation in vitro and in vivo. A series of methods (e.g., RNA-seq, metabolomics, and genetic manipulation) were conducted to reveal the mechanism whereby melatonergic signalling reduces macrophage inflammation. RESULTS: Here, we demonstrate that melatonergic activation substantially lessens interleukin (IL)-1ß-dependent inflammation. Treatment of macrophages with melatonin rewires metabolic program, as well as remodels signalling pathways which depends on interferon regulatory factor (IRF) 7. Mechanistically, melatonin acts via membrane receptor (MT) 1 to increase heat shock factor (Hsf) 1 expression through lowering the inactive glycogen synthase kinase (GSK3) ß, thereby transcriptionally inhibiting interferon (IFN)-γ receptor (IFNGR) 2 and ultimately causing defective canonical signalling events [Janus kinase (JAK) 1/2-signal transducer and activator of transcription (STAT) 1-IRF7] and lower IL-1ß production in macrophages. Moreover, we find that melatonin amplifies host protective responses to PmCQ2 infection-induced pneumonia. CONCLUSIONS: Our conceptual framework provides potential therapeutic targets to prevent and/or treat inflammatory diseases associating with excessive IL-1ß production.


Assuntos
Inflamação/tratamento farmacológico , Interleucina-1beta/antagonistas & inibidores , Fragmentos de Peptídeos/antagonistas & inibidores , Receptores de Interferon/efeitos dos fármacos , Animais , China , Modelos Animais de Doenças , Inflamação/fisiopatologia , Inflamação/prevenção & controle , Camundongos , Receptores de Interferon/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Bioorg Med Chem Lett ; 60: 128574, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35065231

RESUMO

In this work, a series of naringenin-O-carbamate derivatives was designed and synthesized as multifunctional agents for the treatment of Alzheimer's disease (AD) through multi-target-directed ligands (MTDLs) strategy. The biological activity in vitro showed that compound 3c showed good antioxidant potency (ORAC = 1.0 eq), and it was a reversible huAChE (IC50 = 9.7 µM) inhibitor. In addition, compound 3c significantly inhibited self-induced Aß1-42 aggregation, and it could activate UPS degradation pathway in HT22 cells and clear the aggregated proteins associated with AD. Moreover, compound 3c was a selective metal chelator, and it significantly inhibited and disaggregated Cu2+-mediated Aß1-42 aggregation. Furthermore, compound 3c displayed remarkable neuroprotective effect and anti-inflammatory property. Interestingly, compound 3c displayed good hepatoprotective effect by its antioxidant activity. More importantly, compound 3c demonstrated favourable blood-brain barrier penetration in vitro and drug-like property. Therefore, compound 3c was a promising multifunctional agent for the treatment of AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Antioxidantes/farmacologia , Carbamatos/farmacologia , Inibidores da Colinesterase/farmacologia , Flavanonas/farmacologia , Fármacos Neuroprotetores/farmacologia , Acetilcolinesterase/metabolismo , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Animais , Antioxidantes/síntese química , Antioxidantes/química , Butirilcolinesterase/metabolismo , Carbamatos/síntese química , Carbamatos/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Cobre/farmacologia , Relação Dose-Resposta a Droga , Desenvolvimento de Medicamentos , Flavanonas/síntese química , Flavanonas/química , Humanos , Estrutura Molecular , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/metabolismo , Agregados Proteicos/efeitos dos fármacos , Ratos , Relação Estrutura-Atividade
8.
Exp Eye Res ; 216: 108945, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35038456

RESUMO

The VEGF-A-induced functional impairment of the barrier formed by retinal endothelial cells (REC) can be prevented and even - at least temporarily - reverted by trapping the growth factor in a complex with a VEGF-binding protein or by inhibiting the activity of the VEGF receptor 2 (VEGFR2). In an approach to emulate the clinically relevant situation of constant exposure to effectors, we investigated (1) whether prolonged exposure to VEGF-A165 for up to six days results in a different type of disturbance of the barrier formed by immortalized bovine REC (iBREC) and (2) whether alterations of the barrier induced by VEGF-A165 can indeed be sustainably reverted by subsequent treatment with the VEGF-A-binding proteins ranibizumab or brolucizumab. As a measure of barrier integrity, the cell index (CI) of iBREC cultivated on gold electrodes was monitored continuously. CI values declined shortly after addition of the growth factor and then remained low for more than six days over which considerable amounts of both extra- and intracellular VEGF-A were measured. Interestingly, the specific VEGFR2 inhibitor nintedanib normalized the lowered CI when added to iBREC pre-treated with VEGF-A165 for one day, but failed to do so when cells had been exposed to the growth factor for six days. Expression of the tight junction (TJ) protein claudin-5 was unchanged early after addition of VEGF-A165 but higher after prolonged treatment, whereas decreased amounts of the TJ-protein claudin-1 remained low, and increased expression of the plasmalemma vesicle-associated protein (PLVAP) remained high during further exposure. After two days, the characteristic even plasma membrane stainings of claudin-1 or claudin-5 appeared weaker or disordered, respectively. After six days the subcellular localization of claudin-5 was similar to that of control cells again, but claudin-1 remained relocated from the plasma membrane. To counteract these effects of VEGF-A165, brolucizumab or ranibizumab was added after one day, resulting in recovery of the then lowered CI to normal values within a few hours. However, despite the VEGF antagonist being present, the CI declined again two days later to values that were just slightly higher than without VEGF inhibition during further assessment for several days. At this stage, neither the supernatants nor whole cell extracts from iBREC treated with VEGF-A165 and its antagonists contained significant amounts of free VEGF-A. Treatment of VEGF-A165-challenged iBREC with ranibizumab or brolucizumab normalized expression of claudin-1 and claudin-5, but not completely that of PLVAP. Interestingly, the characteristic VEGF-A165-induced relocalization of claudin-1 from the plasma membrane was reverted within one day by any of the VEGF antagonists, but reappeared despite their presence after further exposure for several days. Taken together, barrier dysfunction induced by VEGF-A165 results from deregulated para- and transcellular flow but the precise nature or magnitude of underlying changes on a molecular level clearly depend on the time of exposure, evolving into a stage of VEGF-A165-independent barrier impairment. These findings also provide a plausible explanation for resistance to treatment with VEGF-A antagonists frequently observed in clinical practice.


Assuntos
Células Endoteliais/efeitos dos fármacos , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/farmacologia , Vasos Retinianos/citologia , Junções Íntimas/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Anticorpos Monoclonais Humanizados/uso terapêutico , Transporte Biológico , Western Blotting , Bovinos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Claudina-1/metabolismo , Claudina-5/metabolismo , Eletroforese em Gel de Poliacrilamida , Células Endoteliais/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , Ranibizumab/uso terapêutico
9.
Molecules ; 26(19)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34641559

RESUMO

Alzheimer's disease (AD) is a severe multifactorial neurodegenerative disorder characterized by a progressive loss of neurons in the brain. Despite research efforts, the pathogenesis and mechanism of AD progression are not yet completely understood. There are only a few symptomatic drugs approved for the treatment of AD. The multifactorial character of AD suggests that it is important to develop molecules able to target the numerous pathological mechanisms associated with the disease. Thus, in the context of the worldwide recognized interest of multifunctional ligand therapy, we report herein the synthesis, characterization, physicochemical and biological evaluation of a set of five (1a-e) new ferulic acid-based hybrid compounds, namely feroyl-benzyloxyamidic derivatives enclosing different substituent groups, as potential anti-Alzheimer's disease agents. These hybrids can keep both the radical scavenging activity and metal chelation capacity of the naturally occurring ferulic acid scaffold, presenting also good/mild capacity for inhibition of self-Aß aggregation and fairly good inhibition of Cu-induced Aß aggregation. The predicted pharmacokinetic properties point towards good absorption, comparable to known oral drugs.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Antioxidantes/uso terapêutico , Ácidos Cumáricos/uso terapêutico , Peptídeos beta-Amiloides/antagonistas & inibidores , Antioxidantes/química , Simulação por Computador , Ácidos Cumáricos/química , Humanos , Hidroxilaminas/química , Hidroxilaminas/uso terapêutico , Fragmentos de Peptídeos/antagonistas & inibidores , Relação Estrutura-Atividade
10.
Bioorg Chem ; 116: 105387, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34628225

RESUMO

Alzheimer's disease (AD) is a prevalent neurodegenerative disorder that has multiple causes. Therefore, multiple-target-directed ligands (MTDLs), which act on multiple targets, have been developed as a novel strategy for AD therapy. In this study, novel drug candidates were designed and synthesized by the covalent linkings of tacrine, a previously used anti-AD acetylcholinesterase (AChE) inhibitor, and dipicolylamine, an ß-amyloid (Aß) aggregation inhibitor. Most tacrine-dipicolylamine dimers potently inhibited AChE and Aß1-42 aggregation in vitro, and 13a exhibited nanomolar level inhibition. Molecular docking analysis suggested that 13a could interact with the catalytic active sites and the peripheral anion site of AChE, and bind to Aß1-42 pentamers. Moreover, 13a effectively attenuated Aß1-42 oligomers-induced cognitive dysfunction in mice by activating the cAMP-response element binding protein/brain-derived neurotrophic factor signaling pathway, decreasing tau phosphorylation, preventing synaptic toxicity, and inhibiting neuroinflammation. The safety profile of 13a in mice was demonstrated by acute toxicity experiments. All these results suggested that novel tacrine-dipicolylamine dimers, especially 13a, have multi-target neuroprotective and cognitive-enhancing potentials, and therefore might be developed as MTDLs to combat AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Aminas/farmacologia , Inibidores da Colinesterase/farmacologia , Desenho de Fármacos , Fármacos Neuroprotetores/farmacologia , Ácidos Picolínicos/farmacologia , Tacrina/farmacologia , Acetilcolinesterase/metabolismo , Doença de Alzheimer/metabolismo , Aminas/química , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Humanos , Ligantes , Estrutura Molecular , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/metabolismo , Ácidos Picolínicos/química , Agregados Proteicos/efeitos dos fármacos , Relação Estrutura-Atividade , Tacrina/química
11.
Nat Med ; 27(10): 1718-1724, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34621054

RESUMO

Human immunodeficiency virus (HIV)-1-specific broadly neutralizing monoclonal antibodies are currently under development to treat and prevent HIV-1 infection. We performed a single-center, randomized, double-blind, dose-escalation, placebo-controlled trial of a single administration of the HIV-1 V3-glycan-specific antibody PGT121 at 3, 10 and 30 mg kg-1 in HIV-uninfected adults and HIV-infected adults on antiretroviral therapy (ART), as well as a multicenter, open-label trial of one infusion of PGT121 at 30 mg kg-1 in viremic HIV-infected adults not on ART (no. NCT02960581). The primary endpoints were safety and tolerability, pharmacokinetics (PK) and antiviral activity in viremic HIV-infected adults not on ART. The secondary endpoints were changes in anti-PGT121 antibody titers and CD4+ T-cell count, and development of HIV-1 sequence variations associated with PGT121 resistance. Among 48 participants enrolled, no treatment-related serious adverse events, potential immune-mediated diseases or Grade 3 or higher adverse events were reported. The most common reactions among PGT121 recipients were intravenous/injection site tenderness, pain and headache. Absolute and relative CD4+ T-cell counts did not change following PGT121 infusion in HIV-infected participants. Neutralizing anti-drug antibodies were not elicited. PGT121 reduced plasma HIV RNA levels by a median of 1.77 log in viremic participants, with a viral load nadir at a median of 8.5 days. Two individuals with low baseline viral loads experienced ART-free viral suppression for ≥168 days following antibody infusion, and rebound viruses in these individuals demonstrated full or partial PGT121 sensitivity. The trial met the prespecified endpoints. These data suggest that further investigation of the potential of antibody-based therapeutic strategies for long-term suppression of HIV is warranted, including in individuals off ART and with low viral load.


Assuntos
Antivirais/administração & dosagem , Anticorpos Amplamente Neutralizantes/administração & dosagem , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Adulto , Terapia Antirretroviral de Alta Atividade , Antivirais/imunologia , Antivirais/farmacocinética , Anticorpos Amplamente Neutralizantes/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/virologia , Método Duplo-Cego , Feminino , Proteína gp120 do Envelope de HIV/antagonistas & inibidores , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/genética , Infecções por HIV/patologia , Infecções por HIV/virologia , HIV-1/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/imunologia , Placebos , Carga Viral/efeitos dos fármacos , Carga Viral/imunologia , Adulto Jovem
12.
Neuropeptides ; 90: 102200, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34597878

RESUMO

Glycogen synthase kinase-3 (GSK-3) is a critical molecule in Alzheimer's disease (AD) that modulates two histopathological hallmarks of AD: Amyloid beta (Aß) plaques and neurofibrillary tangles composed of aberrant hyper-phosphorylation of tau protein. This study was performed to investigate the protective effect of flavone apigenin through inhibition of GSK-3 and the involvement of this kinase in the inhibition of BACE1 expression and hyperphosphorylation of tau protein in an AD rat model. 15 nM of aggregated amyloid-beta 25-35 was microinjected into the left lateral ventricle of an AD rat. Apigenin (50 mg/kg) was administered orally 45 min before the Aß injection and continued daily for three weeks. Immunohistochemistry and western blot analysis showed that apigenin significantly reduced the hyperphosphorylation of tau levels in the hippocampus. Real-time PCR analysis revealed significant inhibition of the mRNA level of ß secretase (BACE1) and GSK-3ß, but Apigenin had no effect on the level of GSK-3α. The results demonstrate that apigenin has a protective effect against amyloid-beta 25-35 by decreasing the expression of GSK-3ß with the consequence of lowering the hyperphosphorylation of tau protein and suppressing BACE1 expression.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/toxicidade , Apigenina/farmacologia , Glicogênio Sintase Quinase 3 beta/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/toxicidade , Secretases da Proteína Precursora do Amiloide/biossíntese , Secretases da Proteína Precursora do Amiloide/genética , Animais , Ácido Aspártico Endopeptidases/biossíntese , Ácido Aspártico Endopeptidases/genética , Imuno-Histoquímica , Masculino , Fosforilação , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Wistar , Proteínas tau/metabolismo
13.
Int J Biol Macromol ; 193(Pt A): 1-7, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34687758

RESUMO

Pathological aggregation of amyloid polypeptides is associated with numerous degenerative diseases. Preventing aggregation and clearing amyloid deposits are considered as promising strategies against amyloidosis. With the capacity of crossing the blood-brain barrier and good biocompatibility, the hydroxylated single-walled carbon nanotube (SWCNT-OH) has been shown with excellent anti-amyloid properties. Here, we systematically studied the SWCNT-OH effects on the fibrillization of the ß2m21-31 peptides utilizing all-atom discrete molecular dynamics (DMD) simulation. Our results demonstrated the isolated ß2m21-31 peptides first nucleated into unstructured oligomers followed by coil-to-sheet conformational conversions in oligomers with at least six peptides. The elongation and lateral surfaces of the preformed ß-sheet could catalyze the other unstructured monomers and small oligomers converted into ß-sheet formations via dock-lock fibril growth and secondary nucleation processes. Eventually, the ß2m21-31 peptides would self-assemble into well-ordered cross-ß structures. Regardless of isolated monomers or well-defined cross-ß assemblies, the ß2m21-31 would attach on the surfaces of SWCNT-OH adopting unstructured formations indicating the SWCNT-OH not only inhibited the fibrillization of ß2m21-31 but also destroyed pre-formed proto-fibrils. Overall, our study displays a complete picture of the fibrillization mechanism of ß2m21-31 and the amyloid inhibitory mechanism of SWCNT-OH, offering new insight into the de-novo design of anti-amyloid inhibitors.


Assuntos
Peptídeos beta-Amiloides , Nanotubos de Carbono/química , Fragmentos de Peptídeos , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/química , Humanos , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/química , Agregação Patológica de Proteínas
14.
Chem Biodivers ; 18(12): e2100436, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34664781

RESUMO

Three undescribed hydroxycinnamic acid amide dimers 1-3 were isolated and identified from an extract of Goji berry. Their molecular structures were elucidated based on NMR, MS, and IR spectra analysis. Compounds 1-3 were hydroxycinnamic acid amide dimers, which possess a cyclic butane moiety formed by head-to-head connection. These compounds at 25 µM showed the disaggregation potency on the copper-mediated Aß1-42 aggregation ranging from 27.3±3.2 to 31.0±2.9 %. This study provides new information on the antiaging traditional usage of goji berry.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Amidas/farmacologia , Ácidos Cumáricos/farmacologia , Lycium/química , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Doença de Alzheimer/metabolismo , Amidas/química , Amidas/isolamento & purificação , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Ácidos Cumáricos/química , Ácidos Cumáricos/isolamento & purificação , Relação Dose-Resposta a Droga , Humanos , Conformação Molecular , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Agregados Proteicos/efeitos dos fármacos
15.
Chem Biodivers ; 18(11): e2100341, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34510699

RESUMO

Fifteen chalcone derivatives 3a-3o were synthesized, and evaluated as multifunctional agents against Alzheimer's disease. In vitro studies revealed that these compounds inhibited self-induced Aß1-42 aggregation effectively ranged from 45.9-94.5 % at 20 µM, and acted as potential antioxidants. Their structure-activity relationships were summarized. In particular, (2E)-3-[4-(dimethylamino)phenyl]-1-(pyridin-2-yl)prop-2-en-1-one (3g) exhibited an excellent inhibitory activity of 94.5 % at 20 µM, and it could disassemble the self-induced Aß1-42 aggregation fibrils with ratio of 57.1 % at 20 µM concentration. In addition, compound 3g displayed good chelating ability for Cu2+ , and could effectively inhibit and disaggregate Cu2+ -induced Aß aggregation. Moreover, compound 3g exerted low cytotoxicity, significantly reversed Aß1-42 -induced SH-SY5Y cell damage. More importantly, compound 3g remarkably ameliorated scopolamine-induced memory impairment in mice. In summary, all the results revealed compound 3g was a potential multifunctional agent for AD therapy.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Chalconas/farmacologia , Desenho de Fármacos , Fármacos Neuroprotetores/farmacologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Chalconas/síntese química , Chalconas/química , Cobre/farmacologia , Humanos , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico , Camundongos , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/metabolismo , Agregados Proteicos/efeitos dos fármacos , Escopolamina , Células Tumorais Cultivadas
16.
Eur J Med Chem ; 225: 113821, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34517222

RESUMO

Histone deacetylase 6 (HDAC6) is a potential target for Alzheimer's disease (AD). In this study, a series of novel phenothiazine-, memantine-, and 1,2,3,4-tetrahydro-γ-carboline-based HDAC6 inhibitors with a variety of linker moieties were designed and synthesized. As a hydrochloride salt, the phenothiazine-based hydroxamic acid W5 with a pyridyl-containing linker motif was identified as a high potent and selective HDAC6 inhibitor. It inhibited HDAC6 with an IC50 of 2.54 nM and was more than 290- to 3300-fold selective over other HDAC isoforms. In SH-SY5Y cells, W5 dose-dependently increased the acetylated α-tubulin levels and reduced the hyperphosphorylated tau proteins at Ser396. As an effective metal chelator, W5 inhibited Cu2+-induced Aß1-42 aggregation and disaggregated Cu2+-Aß1-42 oligomers, and showed protective effects on the SH-SY5Y cells against Aß1-42- as well as Cu2+-Aß1-42 induced cell damages, serving as a potential ligand to target AD metal dyshomeostasis. Moreover, W5 promoted the differentiated neuronal neurite outgrowth, increased the mRNA expression of the recognized neurogenesis markers, GAP43, N-myc, and MAP-2. Therefore, W5 might be a good lead for the development of novel HDAC6 inhibitors targeting multi-facets of AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Desacetilase 6 de Histona/antagonistas & inibidores , Inibidores de Histona Desacetilases/farmacologia , Fármacos Neuroprotetores/farmacologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Cobre/metabolismo , Relação Dose-Resposta a Droga , Desacetilase 6 de Histona/metabolismo , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/química , Humanos , Estrutura Molecular , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
17.
Bioorg Med Chem ; 46: 116391, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34488020

RESUMO

Amyloid aggregates of proteins are known to be involved in various diseases such as Alzheimer's disease (AD). It is therefore speculated that the inhibition of amyloid formation can play an important role in the prevention of various diseases involving amyloids. Recently, we have found that acrolein reacts with polyamines, such as spermine, and produces 1,5-diazacyclooctane, such as cyclic spermine (cSPM). cSPM could suppress the aggregation of amyloid ß 1-40 (Aß40), one of the causative proteins of AD. This result suggests the potential inhibitory effect of cSPM against Aß 1-42 (Aß42) and other amyloid protein aggregation which are the main pathological features of AD and other diseases. However, the effect on the aggregation of such proteins remains unclear. In this study, the effect of cSPM on the amyloid formation of Aß42, amylin, and insulin was investigated. These three amyloidogenic proteins forming amyloids under physiological conditions (pH 7.4 and 37℃) served as model and are thought to be the causative proteins of AD, type 2 diabetes, and insulin-derived amyloidosis, respectively. Our results indicate that cSPM can suppress the amyloid aggregation of these proteins and reduce cytotoxicity. This study contributes to a better understanding of means to potentially counteract diseases by the means of polyamine and acrolein.


Assuntos
Acroleína/farmacologia , Compostos Aza/farmacologia , Ciclo-Octanos/farmacologia , Espermina/farmacologia , Acroleína/química , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Compostos Aza/síntese química , Compostos Aza/química , Ciclo-Octanos/síntese química , Ciclo-Octanos/química , Relação Dose-Resposta a Droga , Humanos , Insulina/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas/antagonistas & inibidores , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Estrutura Molecular , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/metabolismo , Agregados Proteicos/efeitos dos fármacos , Espermina/química , Relação Estrutura-Atividade
18.
Bioorg Med Chem Lett ; 51: 128358, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34534674

RESUMO

Histone acetyltransferases (HATs) play a crucial role in post-translational modification. Among them, overexpression, mutation, or hyperfunction of EP300/CBP has been associated with various cancers. In this study, we identified the novel compound 2-chloro-5-[5-[(E)-[1-(3-chlorophenyl)-3-methyl-5-oxo-pyrazol-4-ylidene]methyl]-2-furyl]benzoic acid (1) as an EP300 HAT inhibitor via virtual screening. Further research has been focused on the design, synthesis, and in vitro biological evaluation of virtual hit derivatives. The studies revealed that 4-pyridone-3-carboxylic acid derivatives exhibited bioisosterism of benzoic acid. Replacement proved effective, providing compounds with similar EP300 HAT-inhibitory activity and improved cell growth-inhibitory activity compared to the benzoic acid analogs. Through these studies, we identified a potent and selective EP300/CBP HAT inhibitor.


Assuntos
Antineoplásicos/farmacologia , Ácido Benzoico/farmacologia , Desenho de Fármacos , Proteína p300 Associada a E1A/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Fragmentos de Peptídeos/antagonistas & inibidores , Sialoglicoproteínas/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Ácido Benzoico/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Proteína p300 Associada a E1A/metabolismo , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Fragmentos de Peptídeos/metabolismo , Sialoglicoproteínas/metabolismo , Relação Estrutura-Atividade
19.
Int J Biol Macromol ; 188: 263-271, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34371042

RESUMO

Self-assembly of disordered amyloid-beta (Aß) peptides results in highly ordered amyloid fibrils. The structural information of the early-stage events and also in the presence of inhibitors is of great significance. It is challenging to acquire due to the nature of the amyloids and experimental constraints. Here, we demonstrate the cascade of aggregation (early to late) of the Aß25-35 peptide in the absence and presence of carvedilol, a nonselective ß-adrenergic receptor blocker. The aggregation process of Aß25-35 peptide is monitored using Thioflavin T (ThT) fluorescence, dynamic light scattering (DLS), circular dichroism (CD), Raman spectroscopic techniques, and imaging experiments. We find that the Aß25-35 peptide undergoes an early-stage (3-6 h) helical intermediate formation across the fibrillation pathway using CD and Raman measurements. Carvedilol obstructs the helical intermediate formation of Aß25-35 peptide resulting in inhibition. CD spectra and deconvolution of the Raman bands suggest the ß-sheet formation (24-100 h) in the absence of carvedilol. Spectroscopic results indicate a disordered structure for the peptide in the presence of carvedilol (24-100 h). Electron microscopy (EM) shows the formation of polymorphic fibrils for the peptide alone and non-amyloidal aggregates in the presence of carvedilol. Molecular docking study suggests that the plausible mode of interaction with carvedilol involves the C-terminal residues of the peptide.


Assuntos
Peptídeos beta-Amiloides/química , Amiloide/química , Carvedilol/química , Fragmentos de Peptídeos/química , Amiloide/antagonistas & inibidores , Amiloide/ultraestrutura , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/ultraestrutura , Carvedilol/farmacologia , Dicroísmo Circular , Fluorescência , Humanos , Microscopia Eletrônica , Simulação de Acoplamento Molecular , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/ultraestrutura
20.
Bioorg Med Chem ; 45: 116311, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34304133

RESUMO

A series of novel 2-hydroxybenzylamine-deoxyvasicinone hybrid analogs (8a-8n) have been synthesized and evaluated as inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), and as inhibitors of amyloid peptide (Aß1-42) aggregation, for treatment of Alzheimer's disease (AD). These dual acting compounds exhibited good AChE inhibitory activities ranging from 0.34 to 6.35 µM. Analogs8g and 8n were found to be the most potent AChE inhibitors in the series with IC50values of 0.38 µM and 0.34 µM, respectively. All the analogs (8a-8n) exhibited weak BuChE inhibitory activities ranging from 14.60 to 21.65 µM. Analogs8g and 8n exhibited BuChE with IC50values of 15.38 µM and 14.60 µM, respectively, demonstrating that these analogs were greater than 40-fold more selective for inhibition of AChE over BuChE. Additionally, compounds8g and 8n were also found to be the best inhibitors of self-induced Aß1-42 peptide aggregation with IC50values of 3.91 µM and 3.22 µM, respectively; 8g and 8n also inhibited AChE-induced Aß1-42 peptide aggregation by 68.7% and 72.6%, respectively. Kinetic analysis and molecular docking studies indicate that analogs 8g and 8n bind to a new allosteric pocket (site B) on AChE. In addition, the observed inhibition of AChE-induced Aß1-42 peptide aggregation by 8n is likely due to allosteric inhibition of the binding of this peptide at the CAS site on AChE. Overall, these results indicate that 8g and 8n are examples of dual-acting lead compounds for the development of highly effective anti-AD drugs.


Assuntos
Alcaloides/farmacologia , Doença de Alzheimer/tratamento farmacológico , Benzilaminas/farmacologia , Inibidores da Colinesterase/farmacologia , Fármacos Neuroprotetores/farmacologia , Acetilcolinesterase/metabolismo , Alcaloides/química , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Animais , Benzilaminas/química , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Electrophorus , Cavalos , Humanos , Estrutura Molecular , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/metabolismo , Agregados Proteicos/efeitos dos fármacos , Relação Estrutura-Atividade
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