RESUMO
Lewy body dementia (LBD) represents the second most common neurodegenerative dementia but is a quite underexplored therapeutic area. Nepflamapimod (1) is a brain-penetrant selective inhibitor of the alpha isoform of the mitogen-activated serine/threonine protein kinase (MAPK) p38α, recently repurposed for LBD due to its remarkable antineuroinflammatory properties. Neuroprotective propargylamines are another class of molecules with a therapeutical potential against LBD. Herein, we sought to combine the antineuroinflammatory core of 1 and the neuroprotective propargylamine moiety into a single molecule. Particularly, we inserted a propargylamine moiety in position 4 of the 2,6-dichlorophenyl ring of 1, generating neflamapimod-propargylamine hybrids 3 and 4. These hybrids were evaluated using several cell models, aiming to recapitulate the complexity of LBD pathology through different molecular mechanisms. The N-methyl-N-propargyl derivative 4 showed a nanomolar p38α-MAPK inhibitory activity (IC50 = 98.7 nM), which is only 2.6-fold lower compared to that of the parent compound 1, while displaying no hepato- and neurotoxicity up to 25 µM concentration. It also retained a similar immunomodulatory profile against the N9 microglial cell line. Gratifyingly, at 5 µM concentration, 4 demonstrated a neuroprotective effect against dexamethasone-induced reactive oxygen species production in neuronal cells that was higher than that of 1.
Assuntos
Indanos , Doença por Corpos de Lewy , Fármacos Neuroprotetores , Humanos , Doença por Corpos de Lewy/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/síntese química , Indanos/farmacologia , Indanos/química , Indanos/síntese química , Animais , Relação Estrutura-Atividade , Estrutura Molecular , Relação Dose-Resposta a Droga , CamundongosRESUMO
There is growing evidence that membrane transporters expressed at the blood-brain barrier (BBB) and brain parenchymal cells play an important role in Alzheimer's disease (AD) development and progression. However, quantitative information about changes in transporter protein expression at neurovascular unit cells in AD is limited. Here, we studied the changes in the absolute protein expression of five ATP-binding cassette (ABC) and thirteen solute carrier (SLC) transporters in the isolated brain microvessels and brain cortical tissue of TgF344-AD rats compared to age-matched wild-type (WT) animals using liquid chromatography tandem mass spectrometry based quantitative targeted absolute proteomic analysis. Moreover, sex-specific alterations in transporter expression in the brain cortical tissue of this model were examined. Protein expressions of Abcg2, Abcc1 and FATP1 (encoded by Slc27a1) in the isolated brain microvessels of TgF344-AD rats were 3.1-, 2.0-, 4.3-fold higher compared to WT controls, respectively (p < 0.05). Abcc1 and 4F2hc (encoded by Slc3a2) protein expression was significantly up-regulated in the brain cortical tissue of male TgF344-AD rats compared to male WT rats (p < 0.05). The study provides novel information for the elucidation of molecular mechanisms underlying AD and valuable knowledge about the optimal use of the TgF344-AD rat model in AD drug development and drug delivery research.
Assuntos
Doença de Alzheimer , Doença de Alzheimer/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Feminino , Masculino , Proteínas de Membrana Transportadoras , Microvasos/metabolismo , Proteômica/métodos , RatosRESUMO
Hormonal contraceptives prevent ovulation with subsequent reduction in endogenous levels of estradiol, progesterone and its neuroactive metabolite allopregnanolone. These neurosteroids modulate several brain functions, including neuronal plasticity, cognition and memory. We hypothesized that hormonal contraceptives might affect synaptic plasticity, learning and memory, as a consequence of suppressed endogenous hormones levels. Female rats were orally treated with a combination of ethinyl estradiol (EE, 0.020 mg) and levonorgestrel (LNG, 0.060 mg) once daily for four weeks. Decreased hippocampal brain-derived neurotrophic factor (BDNF) levels and altered histone H3 post-translational modifications (PTMs) were observed 14 days after discontinuation from chronic EE-LNG treatment. These effects were not accompanied by alterations in long-term plasticity at glutamatergic synapses, recognition memory in the novel object and novel place location tests, or spatial learning, memory, and behavioral flexibility in the Morris water maze test. Thus, decreased BDNF content does not affect synaptic plasticity and cognitive performance; rather it might be relevant for the occurrence of certain psychiatric symptoms, reported by some women using hormonal contraceptives. These results provide the first evidence of hippocampal epigenetic changes induced by hormonal contraceptives and complement previous studies on the neurobiological actions of hormonal contraceptives; the finding that effects of chronic EE-LNG treatment on BDNF content and histone PTMs are observed 14 days after drug discontinuation warrants further investigation to better understand the implications of such long-term consequences for women's health.
Assuntos
Fator Neurotrófico Derivado do Encéfalo , Histonas , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Anticoncepcionais/metabolismo , Anticoncepcionais/farmacologia , Feminino , Hipocampo , Histonas/metabolismo , Humanos , Plasticidade Neuronal , Processamento de Proteína Pós-Traducional , RatosRESUMO
Despite Alzheimer's disease (AD) incidence being projected to increase worldwide, the drugs currently on the market can only mitigate symptoms. Considering the failures of the classical paradigm "one target-one drug-one disease" in delivering effective medications for AD, polypharmacology appears to be a most viable therapeutic strategy. Polypharmacology can involve combinations of multiple drugs and/or single chemical entities modulating multiple targets. Taking inspiration from an ongoing clinical trial, this work aims to convert a promising cromolyn-ibuprofen drug combination into single-molecule "codrugs." Such codrugs should be able to similarly modulate neuroinflammatory and amyloid pathways, while showing peculiar pros and cons. By exploiting a linking strategy, we designed and synthesized a small set of cromolyn-ibuprofen conjugates (4-6). Preliminary plasma stability and neurotoxicity assays allowed us to select diamide 5 and ethanolamide 6 as promising compounds for further studies. We investigated their immunomodulatory profile in immortalized microglia cells, in vitro anti-aggregating activity towards Aß42-amyloid self-aggregation, and their cellular neuroprotective effect against Aß42-induced neurotoxicity. The fact that 6 effectively reduced Aß-induced neuronal death, prompted its investigation into an in vivo model. Notably, 6 was demonstrated to significantly increase the longevity of Aß42-expressing Drosophila and to improve fly locomotor performance.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Cromolina Sódica/uso terapêutico , Ibuprofeno/uso terapêutico , Polifarmacologia , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/toxicidade , Animais , Comportamento Animal/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromolina Sódica/síntese química , Cromolina Sódica/química , Cromolina Sódica/farmacologia , Drosophila/efeitos dos fármacos , Desenho de Fármacos , Endocitose/efeitos dos fármacos , Ibuprofeno/síntese química , Ibuprofeno/química , Ibuprofeno/farmacologia , Imunomodulação/efeitos dos fármacos , Camundongos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Neurotoxinas/toxicidade , Agregados Proteicos/efeitos dos fármacos , Ratos WistarRESUMO
Our goal was the evaluation of a series of N-1,2,3-triazole-isatin derivatives for multi-target activity which included cholinesterase (ChE) inhibition and ß-amyloid (Aß) peptide anti-aggregation. The compounds have shown considerable promise as butyrylcholinesterase (BuChE) inhibitors. Although the inhibition of eel acetylcholinesterase (eeAChE) was weak, the inhibitions against equine BuChE (eqBuChE) and human BuChE (hBuChE) were more significant with a best inhibition against eqBuChE of 0.46 µM. In some cases, these molecules gave better inhibitions for hBuChE than eqBuChE. For greater insights into their mode of action, molecular docking studies were carried out, followed by STD-NMR validation. In addition, some of these compounds showed weak Aß anti-aggregation activity. Hepatotoxicity studies showed that they were non-hepatoxic and neurotoxicity studies using neurite outgrowth experiments led to the conclusion that these compounds are only weakly neurotoxic.
Assuntos
Acetilcolinesterase/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Isatina/farmacologia , Triazóis/farmacologia , Peptídeos beta-Amiloides/metabolismo , Animais , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Electrophorus , Células Hep G2 , Cavalos , Humanos , Isatina/química , Estrutura Molecular , Agregados Proteicos , Relação Estrutura-Atividade , Triazóis/químicaRESUMO
Aspartate-Glutamate Carrier 1 (AGC1) deficiency is a rare neurological disease caused by mutations in the solute carrier family 25, member 12 (SLC25A12) gene, encoding for the mitochondrial aspartate-glutamate carrier isoform 1 (AGC1), a component of the malate-aspartate NADH shuttle (MAS), expressed in excitable tissues only. AGC1 deficiency patients are children showing severe hypotonia, arrested psychomotor development, seizures and global hypomyelination. While the effect of AGC1 deficiency in neurons and neuronal function has been deeply studied, little is known about oligodendrocytes and their precursors, the brain cells involved in myelination. Here we studied the effect of AGC1 down-regulation on oligodendrocyte precursor cells (OPCs), using both in vitro and in vivo mouse disease models. In the cell model, we showed that a reduced expression of AGC1 induces a deficit of OPC proliferation leading to their spontaneous and precocious differentiation into oligodendrocytes. Interestingly, this effect seems to be related to a dysregulation in the expression of trophic factors and receptors involved in OPC proliferation/differentiation, such as Platelet-Derived Growth Factor α (PDGFα) and Transforming Growth Factor ßs (TGFßs). We also confirmed the OPC reduction in vivo in AGC1-deficent mice, as well as a proliferation deficit in neurospheres from the Subventricular Zone (SVZ) of these animals, thus indicating that AGC1 reduction could affect the proliferation of different brain precursor cells. These data clearly show that AGC1 impairment alters myelination not only by acting on N-acetyl-aspartate production in neurons but also on OPC proliferation and suggest new potential therapeutic targets for the treatment of AGC1 deficiency.
Assuntos
Sistemas de Transporte de Aminoácidos Acídicos/deficiência , Antiporters/deficiência , Mitocôndrias/metabolismo , Células Precursoras de Oligodendrócitos/citologia , Células Precursoras de Oligodendrócitos/metabolismo , Trifosfato de Adenosina/metabolismo , Sistemas de Transporte de Aminoácidos Acídicos/metabolismo , Animais , Antiporters/metabolismo , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Regulação para Baixo , Inativação Gênica , Lactatos/metabolismo , Ventrículos Laterais/metabolismo , Potencial da Membrana Mitocondrial , Camundongos , Neurônios/metabolismo , Fator de Crescimento Derivado de Plaquetas , Espécies Reativas de Oxigênio/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismoRESUMO
The mitochondrial aspartate-glutamate carrier isoform 1 (AGC1) catalyzes a Ca2+-stimulated export of aspartate to the cytosol in exchange for glutamate, and is a key component of the malate-aspartate shuttle which transfers NADH reducing equivalents from the cytosol to mitochondria. By sustaining the complete glucose oxidation, AGC1 is thought to be important in providing energy for cells, in particular in the CNS and muscle where this protein is mainly expressed. Defects in the AGC1 gene cause AGC1 deficiency, an infantile encephalopathy with delayed myelination and reduced brain N-acetylaspartate (NAA) levels, the precursor of myelin synthesis in the CNS. Here, we show that undifferentiated Neuro2A cells with down-regulated AGC1 display a significant proliferation deficit associated with reduced mitochondrial respiration, and are unable to synthesize NAA properly. In the presence of high glutamine oxidation, cells with reduced AGC1 restore cell proliferation, although oxidative stress increases and NAA synthesis deficit persists. Our data suggest that the cellular energetic deficit due to AGC1 impairment is associated with inappropriate aspartate levels to support neuronal proliferation when glutamine is not used as metabolic substrate, and we propose that delayed myelination in AGC1 deficiency patients could be attributable, at least in part, to neuronal loss combined with lack of NAA synthesis occurring during the nervous system development.
Assuntos
Sistemas de Transporte de Aminoácidos/biossíntese , Ácido Aspártico/análogos & derivados , Proliferação de Células , Regulação para Baixo , Proteínas Mitocondriais/biossíntese , Neurônios/metabolismo , Sistemas de Transporte de Aminoácidos Acídicos/deficiência , Sistemas de Transporte de Aminoácidos Acídicos/genética , Sistemas de Transporte de Aminoácidos Acídicos/metabolismo , Antiporters/deficiência , Antiporters/genética , Antiporters/metabolismo , Ácido Aspártico/biossíntese , Linhagem Celular , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/genética , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/metabolismo , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/patologia , Humanos , Doenças Mitocondriais/genética , Doenças Mitocondriais/metabolismo , Doenças Mitocondriais/patologia , Neurônios/patologia , Transtornos Psicomotores/genética , Transtornos Psicomotores/metabolismo , Transtornos Psicomotores/patologiaRESUMO
Alzheimer's disease (AD) is a progressive neurodegenerative disease impacting the lives of millions of people worldwide. The formation of amyloid ß (Aß) plagues in the brain is the main pathological hallmark of AD. The Aß deposits are formed due to the imbalance between the production and Aß clearance in the brain and across the blood-brain barrier (BBB). In this respect, low-density lipoprotein receptor-related protein 1 (LRP1) plays a significant role by mediating both brain Aß production and clearance. Due to its important role in AD pathogenesis, LRP1 is considered an attractive drug target for AD therapies. In the present review, we summarize the current knowledge about the role of LRP1 in AD pathogenesis as well as recent findings on changes in LRP1 expression and function in AD. Finally, we discuss the advances in utilizing LRP1 as a drug target for AD treatments as well as future perspectives on LRP1 research.
RESUMO
Alzheimer's disease (AD) is the most common cause of dementia. Despite intensive research efforts, there are currently no effective treatments to cure and prevent AD. There is growing evidence that dysregulation of iron homeostasis may contribute to the pathogenesis of AD. Given the important role of the transferrin receptor 1 (TfR1) in regulating iron distribution in the brain, as well as in the drug delivery, we investigated its expression in the brain cortex and isolated brain microvessels from female 8-month-old 5xFAD mice mimicking advanced stage of AD. Moreover, we explored the association between the TfR1 expression and the activation of the HIF-1 signaling pathway, as well as oxidative stress and inflammation in 5xFAD mice. Finally, we studied the impact of Aß1-40 and Aß1-42 on TfR1 expression in the brain endothelial cell line hCMEC/D3. In the present study, we revealed that an increase in TfR1 protein levels observed in the brain cortex of 5xFAD mice was associated with activation of the HIF-1 signaling pathway as well as accompanied by oxidative stress and inflammation. Interestingly, incubation of Aß peptides in hCMEC/D3 cells did not affect the expression of TfR1, which supported our findings of unaltered TfR1 expression in the isolated brain microvessels in 5xFAD mice. In conclusion, the study provides important information about the expression of TfR1 in the 5xFAD mouse model and the potential role of HIF-1 signaling pathway in the regulation of TfR1 in AD, which could represent a promising strategy for the development of therapies for AD.
Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Córtex Cerebral , Modelos Animais de Doenças , Camundongos Transgênicos , Estresse Oxidativo , Receptores da Transferrina , Transdução de Sinais , Animais , Receptores da Transferrina/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Feminino , Peptídeos beta-Amiloides/metabolismo , Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Microvasos/metabolismo , Microvasos/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Inflamação/metabolismo , Inflamação/patologia , Fragmentos de PeptídeosRESUMO
Triple negative breast cancer (TNBC) is among the most aggressive and deadly cancer subtypes. Intra-tumoral hypoxia is associated with aggressiveness and drug resistance in TNBC. One of the underlying mechanisms of hypoxia-induced drug resistance is the elevated expression of efflux transporters such as breast cancer resistant protein (ABCG2). In the present study, we investigated the possibility of ameliorating ABCG2-mediated drug resistance in hypoxic TNBC cells by monoacylglycerol lipase (MAGL) inhibition and the consequent downregulation of ABCG2 expression. The effect of MAGL inhibition on ABCG2 expression, function, and efficacy of regorafenib, an ABCG2 substrate was investigated in cobalt dichloride (CoCl2) induced pseudohypoxic TNBC (MDA-MB-231) cells, using quantitative targeted absolute proteomics, qRT-PCR, anti-cancer drug accumulation in the cells, cell invasiveness and resazurin-based cell viability assays. Our results showed that hypoxia-induced ABCG2 expression led to low regorafenib intracellular concentrations, reduced the anti-invasiveness efficacy, and elevated half maximal inhibitory concentration (IC50) of regorafenib in vitro MDA-MB-231 cells. MAGL inhibitor, JJKK048, reduced ABCG2 expression, increased regorafenib cell accumulation, which led to higher regorafenib efficacy. In conclusion, hypoxia-induced regorafenib resistance due to ABCG2 over-expression in TNBC cells can be ameliorated by MAGL inhibition.
Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Monoacilglicerol Lipases/metabolismo , Monoacilglicerol Lipases/farmacologia , Linhagem Celular Tumoral , Hipóxia , Resistencia a Medicamentos Antineoplásicos , Proteínas de Neoplasias/metabolismoRESUMO
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease without any effective treatment. Protein TDP-43 is a pathological hallmark of ALS in both sporadic and familiar patients. Post-translational modifications of TDP-43 promote its aggregation in the cytoplasm. Tau-Tubulin kinase (TTBK1) phosphorylates TDP-43 in cellular and animal models; thus, TTBK1 inhibitors emerge as a promising therapeutic strategy for ALS. The design, synthesis, biological evaluation, kinase-ligand complex structure determination, and molecular modeling studies confirmed novel pyrrolopyrimidine derivatives as valuable inhibitors for further development. Moreover, compound 29 revealed good brain penetration in vivo and was able to reduce TDP-43 phosphorylation not only in cell cultures but also in the spinal cord of transgenic TDP-43 mice. A shift to M2 anti-inflammatory microglia was also demonstrated in vivo. Both these activities led to motor neuron preservation in mice, proposing pyrrolopyrimidine 29 as a valuable lead compound for future ALS therapy.
Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Inflamação/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Animais , Encéfalo/metabolismo , Estudos de Casos e Controles , Humanos , Inflamação/metabolismo , Inflamação/patologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Fosforilação , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacocinética , Ratos , Ratos Wistar , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Distribuição TecidualRESUMO
Microglial cells, the immune cells of the central nervous system (CNS), play a crucial role for the proper brain development and function and in CNS homeostasis. While in physiological conditions, microglia continuously check the state of brain parenchyma, in pathological conditions, microglia can show different activated phenotypes: In the early phases, microglia acquire the M2 phenotype, increasing phagocytosis and releasing neurotrophic and neuroprotective factors. In advanced phases, they acquire the M1 phenotype, becoming neurotoxic and contributing to neurodegeneration. Underlying this phenotypic change, there is a switch in the expression of specific microglial genes, in turn modulated by epigenetic changes, such as DNA methylation, histones post-translational modifications and activity of miRNAs. New roles are attributed to microglial cells, including specific communication with neurons, both through direct cell-cell contact and by release of many different molecules, either directly or indirectly, through extracellular vesicles. In this review, recent findings on the bidirectional interaction between neurons and microglia, in both physiological and pathological conditions, are highlighted, with a focus on the complex field of microglia immunomodulation through epigenetic mechanisms and/or released factors. In addition, advanced technologies used to study these mechanisms, such as microfluidic, 3D culture and in vivo imaging, are presented.
Assuntos
Epigênese Genética/genética , Microglia/metabolismo , Animais , Metilação de DNA/genética , Exossomos/genética , Humanos , MicroRNAs/genética , Microfluídica , Processamento de Proteína Pós-Traducional/genéticaRESUMO
Dementia is a pathological condition characterized by a decline in memory, as well as in other cognitive and social functions. The cellular and molecular mechanisms of brain damage in dementia are not completely understood; however, neuroinflammation is involved. Evidence suggests that chronic inflammation may impair cognitive performance and that dietary protein source may differentially influence this process. Dietary protein source has previously been shown to modify systemic inflammation in mouse models. Thus, we aimed to investigate the effect of chronic dietary protein source substitution in an ageing and dementia male mouse model, the senescence-accelerated mouse-prone 8 (SAMP8) model. We observed that dietary protein source differentially modified memory as shown by inhibitory avoidance testing at 4 months of age. Also, dietary protein source differentially modified neuroinflammation and gliosis in male SAMP8 mice. Our results suggest that chronic dietary protein source substitution may influence brain ageing and memory-related mechanisms in male SAMP8 mice. Moreover, the choice of dietary protein source in mouse diets for experimental purposes may need to be carefully considered when interpreting results.
Assuntos
Envelhecimento/patologia , Demência/patologia , Demência/fisiopatologia , Proteínas Alimentares/efeitos adversos , Encefalite/patologia , Encefalite/fisiopatologia , Memória , Animais , Astrócitos/patologia , Autofagia , Biomarcadores/metabolismo , Peso Corporal , Cognição , Demência/complicações , Modelos Animais de Doenças , Encefalite/complicações , Comportamento Alimentar , Gliose/complicações , Gliose/patologia , Gliose/fisiopatologia , Masculino , Microglia/patologia , Fator de Crescimento Neural/metabolismo , Neurogênese , Oligodendroglia/patologiaRESUMO
Mitochondrial aspartate-glutamate carrier isoform 1 (AGC1) deficiency is an ultra-rare genetic disease characterized by global hypomyelination and brain atrophy, caused by mutations in the SLC25A12 gene leading to a reduction in AGC1 activity. In both neuronal precursor cells and oligodendrocytes precursor cells (NPCs and OPCs), the AGC1 determines reduced proliferation with an accelerated differentiation of OPCs, both associated with gene expression dysregulation. Epigenetic regulation of gene expression through histone acetylation plays a crucial role in the proliferation/differentiation of both NPCs and OPCs and is modulated by mitochondrial metabolism. In AGC1 deficiency models, both OPCs and NPCs show an altered expression of transcription factors involved in the proliferation/differentiation of brain precursor cells (BPCs) as well as a reduction in histone acetylation with a parallel alteration in the expression and activity of histone acetyltransferases (HATs) and histone deacetylases (HDACs). In this study, histone acetylation dysfunctions have been dissected in in vitro models of AGC1 deficiency OPCs (Oli-Neu cells) and NPCs (neurospheres), in physiological conditions and following pharmacological treatments. The inhibition of HATs by curcumin arrests the proliferation of OPCs leading to their differentiation, while the inhibition of HDACs by suberanilohydroxamic acid (SAHA) has only a limited effect on proliferation, but it significantly stimulates the differentiation of OPCs. In NPCs, both treatments determine an alteration in the commitment toward glial cells. These data contribute to clarifying the molecular and epigenetic mechanisms regulating the proliferation/differentiation of OPCs and NPCs. This will help to identify potential targets for new therapeutic approaches that are able to increase the OPCs pool and to sustain their differentiation toward oligodendrocytes and to myelination/remyelination processes in AGC1 deficiency, as well as in other white matter neuropathologies.
RESUMO
Thanks to the widespread use and safety profile of donepezil (1) in the treatment of Alzheimer's disease (AD), one of the most widely adopted multi-target-directed ligand (MTDL) design strategies is to modify its molecular structure by linking a second fragment carrying an additional AD-relevant biological property. Herein, supported by a proposed combination therapy of 1 and the quinone drug idebenone, we rationally designed novel 1-based MTDLs targeting Aß and oxidative pathways. By exploiting a bioisosteric replacement of the indanone core of 1 with a 1,4-naphthoquinone, we ended up with a series of highly merged derivatives, in principle devoid of the "physicochemical challenge" typical of large hybrid-based MTDLs. A preliminary investigation of their multi-target profile identified 9, which showed a potent and selective butyrylcholinesterase inhibitory activity, together with antioxidant and antiaggregating properties. In addition, it displayed a promising drug-like profile.
Assuntos
Donepezila/química , Ligantes , Fármacos Neuroprotetores/química , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Barreira Hematoencefálica/diagnóstico por imagem , Barreira Hematoencefálica/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Inibidores da Colinesterase/química , Inibidores da Colinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/uso terapêutico , Donepezila/metabolismo , Donepezila/farmacologia , Donepezila/uso terapêutico , Desenho de Fármacos , Humanos , Indanos/química , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Agregados Proteicos/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
Since 2002, no clinical candidate against Alzheimer's disease has reached the market; hence, an effective therapy is urgently needed. We followed the so-called "multitarget directed ligand" approach and designed 36 novel tacrine-phenothiazine heterodimers which were in vitro evaluated for their anticholinesterase properties. The assessment of the structure-activity relationships of such derivatives highlighted compound 1dC as a potent and selective acetylcholinesterase inhibitor with IC50 = 8 nM and 1aA as a potent butyrylcholinesterase inhibitor with IC50 = 15 nM. Selected hybrids, namely, 1aC, 1bC, 1cC, 1dC, and 2dC, showed a significant inhibitory activity toward τ(306-336) peptide aggregation with percent inhibition ranging from 50.5 to 62.1%. Likewise, 1dC and 2dC exerted a remarkable ability to inhibit self-induced Aß1-42 aggregation. Notwithstanding, in vitro studies displayed cytotoxicity toward HepG2 cells and cerebellar granule neurons; no pathophysiological abnormality was observed when 1dC was administered to mice at 14 mg/kg (i.p.). 1dC was also able to permeate to the CNS as shown by in vitro and in vivo models. The maximum brain concentration was close to the IC50 value for acetylcholinesterase inhibition with a relatively slow elimination half-time. 1dC showed an acceptable safety and good pharmacokinetic properties and a multifunctional biological profile.
Assuntos
Doença de Alzheimer , Tacrina , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides , Animais , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Desenho de Fármacos , Camundongos , Fenotiazinas/farmacologia , Relação Estrutura-Atividade , Tacrina/farmacologiaRESUMO
Multiple sclerosis (MS) is a complex inflammatory, degenerative, and demyelinating disease of the central nervous system. Although treatments exist, MS cannot be cured by available drugs, which primarily target neuroinflammation. Thus, it is feasible that a well concerted polypharmacological approach able to act at multiple points within the intricate network of inflammation, neurodegeneration, and demyelination/remyelination pathways would succeed where other drugs have failed. Starting from reported beneficial effects of α-linolenic acid (ALA) and valproic acid (VPA) in MS, and by applying a rational strategy, we developed a small set of codrugs obtained by conjugating VPA and ALA through proper linkers. A cellular profiling identified 1 as a polypharmacological tool able not only to modulate microglia polarization, but also to counteract neurodegeneration and demyelination and induce oligodendrocyte precursor cell differentiation, by acting on multiple biochemical and epigenetic pathways.
RESUMO
Overcoming the lack of effective treatments and the continuous clinical trial failures in neurodegenerative drug discovery might require a shift from the prevailing paradigm targeting pathogenesis to the one targeting simultaneously neuroprotection and neuroregeneration. In the studies reported herein, we sought to identify small molecules that might exert neuroprotective and neuroregenerative potential as tools against neurodegenerative diseases. In doing so, we started from the reported neuroprotective/neuroregenerative mechanisms of psychotropic drugs featuring a tricyclic alkylamine scaffold. Thus, we designed a focused-chemical library of 36 entries aimed at exploring the structural requirements for efficient neuroprotective/neuroregenerative cellular activity, without the manifestation of toxicity. To this aim, we developed a synthetic protocol, which overcame the limited applicability of previously reported procedures. Next, we evaluated the synthesized compounds through a phenotypic screening pipeline, based on primary neuronal systems. Phenothiazine 2Bc showed improved neuroregenerative and neuroprotective properties with respect to reference drug desipramine (2Aa). Importantly, we have also shown that 2Bc outperformed currently available drugs in cell models of Alzheimer's and Parkinson's diseases and attenuates microglial activation by reducing iNOS expression.
Assuntos
Descoberta de Drogas/métodos , Regeneração Nervosa/efeitos dos fármacos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Psicotrópicos/química , Psicotrópicos/farmacologia , Animais , Animais Recém-Nascidos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/fisiologia , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Regeneração Nervosa/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Ratos , Ratos WistarRESUMO
We have designed and synthesized a series of 14 hybrid molecules out of the cholinesterase (ChE) inhibitor tacrine and a benzimidazole-based human cannabinoid receptor subtype 2 (hCB2R) agonist and investigated them in vitro and in vivo. The compounds are potent ChE inhibitors, and for the most promising hybrids, the mechanism of human acetylcholinesterase (hAChE) inhibition as well as their ability to interfere with AChE-induced aggregation of ß-amyloid (Aß), and Aß self-aggregation was assessed. All hybrids were evaluated for affinity and selectivity for hCB1R and hCB2R. To ensure that the hybrids retained their agonist character, the expression of cAMP-regulated genes was quantified, and potency and efficacy were determined. Additionally, the effects of the hybrids on microglia activation and neuroprotection on HT-22 cells were investigated. The most promising in vitro hybrids showed pronounced neuroprotection in an Alzheimer's mouse model at low dosage (0.1 mg/kg, i.p.), lacking hepatotoxicity even at high dose (3 mg/kg, i.p.).
Assuntos
Colinesterases/metabolismo , Fármacos Neuroprotetores/farmacologia , Receptor CB2 de Canabinoide/metabolismo , Animais , Humanos , Ligantes , CamundongosRESUMO
To address the multifactorial nature of Alzheimer's Disease (AD), a multi-target-directed ligand approach was herein developed. As a follow-up of our previous studies, a small library of newly designed 2-arylbenzofuran derivatives was evaluated towards cholinesterases and cannabinoid receptors. The two most promising compounds, 8 and 10, were then assessed for their neuroprotective activity and for their ability to modulate the microglial phenotype. Compound 8 emerged as able to fight AD from several directions: it restored the cholinergic system by inhibiting butyrylcholinesterase, showed neuroprotective activity against Aß1-42 oligomers, was a potent and selective CB2 ligand and had immunomodulatory effects, switching microglia from the pro-inflammatory M1 to the neuroprotective M2 phenotype. Derivative 10 was a potent CB2 inverse agonist with promising immunomodulatory properties and could be considered as a tool for investigating the role of CB2 receptors and for developing potential immunomodulating drugs addressing the endocannabinoid system.