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1.
Sci Adv ; 10(15): eadm7600, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608019

RESUMO

Myelination is essential for neuronal function and health. In peripheral nerves, >100 causative mutations have been identified that cause Charcot-Marie-Tooth disease, a disorder that can affect myelin sheaths. Among these, a number of mutations are related to essential targets of the posttranslational modification neddylation, although how these lead to myelin defects is unclear. Here, we demonstrate that inhibiting neddylation leads to a notable absence of peripheral myelin and axonal loss both in developing and regenerating mouse nerves. Our data indicate that neddylation exerts a global influence on the complex transcriptional and posttranscriptional program by simultaneously regulating the expression and function of multiple essential myelination signals, including the master transcription factor EGR2 and the negative regulators c-Jun and Sox2, and inducing global secondary changes in downstream pathways, including the mTOR and YAP/TAZ signaling pathways. This places neddylation as a critical regulator of myelination and delineates the potential pathogenic mechanisms involved in CMT mutations related to neddylation.


Assuntos
Doença de Charcot-Marie-Tooth , Células de Schwann , Animais , Camundongos , Bainha de Mielina/genética , Doença de Charcot-Marie-Tooth/genética , Mutação , Processamento de Proteína Pós-Traducional
2.
Autophagy ; 18(6): 1297-1317, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34520334

RESUMO

Cerebral ischemia is a pathology involving a cascade of cellular mechanisms, leading to the deregulation of proteostasis, including macroautophagy/autophagy, and finally to neuronal death. If it is now accepted that cerebral ischemia induces autophagy, the effect of thrombolysis/energy recovery on proteostasis remains unknown. Here, we investigated the effect of thrombolysis by PLAT/tPA (plasminogen activator, tissue) on autophagy and neuronal death. In two in vitro models of hypoxia reperfusion and an in vivo model of thromboembolic stroke with thrombolysis by PLAT/tPA, we found that ischemia enhances neuronal deleterious autophagy. Interestingly, PLAT/tPA decreases autophagy to mediate neuroprotection by modulating the PI3K-AKT-MTOR pathways both in vitro and in vivo. We identified IGF1R (insulin-like growth factor I receptor; a tyrosine kinase receptor) as the effective receptor and showed in vitro, in vivo and in human stroke patients and that PLAT/tPA is able to degrade IGFBP3 (insulin-like growth factor binding protein 3) to increase IGF1 (insulin-like growth factor 1) bioavailability and thus IGF1R activation.Abbreviations: AKT/protein kinase B: thymoma viral proto-oncogene 1; EGFR: epidermal growth factor receptor; Hx: hypoxia; IGF1: insulin-like growth factor 1; IGF1R: insulin-like growth factor I receptor; IGFBP3: insulin-like growth factor binding protein 3; Ka: Kainate; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MAPK/ERK: mitogen-activated protein kinase; MTOR: mechanistic target of rapamycin kinase; MTORC1: MTOR complex 1; OGD: oxygen and glucose deprivation; OGDreox: oxygen and glucose deprivation + reoxygentation; PepA: pepstatin A1; PI3K: phosphoinositide 3-kinase; PLAT/tPA: plasminogen activator, tissue; PPP: picropodophyllin; SCH77: SCH772984; ULK1: unc-51 like kinase 1; Wort: wortmannin.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Autofagia , Isquemia Encefálica/tratamento farmacológico , Glucose/farmacologia , Humanos , Hipóxia , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/farmacologia , Fator de Crescimento Insulin-Like I/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Oxigênio/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Acidente Vascular Cerebral/tratamento farmacológico , Serina-Treonina Quinases TOR/metabolismo , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/metabolismo , Ativador de Plasminogênio Tecidual/farmacologia
3.
J Thromb Haemost ; 19(9): 2235-2247, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34060720

RESUMO

BACKGROUND: Factor XII (FXII) is a serine protease that participates in the intrinsic coagulation pathway. Several studies have shown that plasma FXII exerts a deleterious role in cerebral ischemia and traumatic brain injury by promoting thrombo-inflammation. Nevertheless, the impact of FXII on neuronal cell fate remains unknown. OBJECTIVES: We investigated the role of FXII and FXIIa in neuronal injury and apoptotic cell death. METHODS: We tested the neuroprotective roles of FXII and FXIIa in an experimental model of neuronal injury induced by stereotaxic intracerebral injection of N-methyl-D-aspartic acid (NMDA) in vivo and in a model of apoptotic death of murine primary neuronal cultures through serum deprivation in vitro. RESULTS: Here, we found that exogenous FXII and FXIIa reduce brain lesions induced by NMDA injection in vivo. Furthermore, FXII protects cultured neurons from apoptosis through a growth factor--like effect. This mechanism was triggered by direct interaction with epidermal growth factor (EGF) receptor and subsequent activation of this receptor. Interestingly, the "proteolytically" active and two-chain form of FXII, FXIIa, exerts its protective effects by an alternative signaling pathway. FXIIa activates the pro-form of hepatocyte growth factor (HGF) into HGF, which in turn activated the HGF receptor (HGFR) pathway. CONCLUSION: This study describes two novel mechanisms of action of FXII and identifies neurons as target cells for the protective effects of single and two-chain forms of FXII. Therefore, inhibition of FXII in neurological disorders may have deleterious effects by preventing its beneficial effects on neuronal survival.


Assuntos
Fator XII , Proteínas Proto-Oncogênicas c-met , Animais , Apoptose , Coagulação Sanguínea , Fator XIIa , Camundongos , Neurônios
4.
Brain Behav Immun ; 91: 649-667, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33017613

RESUMO

For the last two decades, researchers have placed hopes in a new era in which a combination of reperfusion and neuroprotection would revolutionize the treatment of stroke. Nevertheless, despite the thousands of papers available in the literature showing positive results in preclinical stroke models, randomized clinical trials have failed to show efficacy. It seems clear now that the existing data obtained in preclinical research have depicted an incomplete picture of stroke pathophysiology. In order to ameliorate bench-to-bed translation, in this review we first describe the main actors on stroke inflammatory and immune responses based on the available preclinical data, highlighting the fact that the link between leukocyte infiltration, lesion volume and neurological outcome remains unclear. We then describe what is known on neuroinflammation and immune responses in stroke patients, and summarize the results of the clinical trials on immunomodulatory drugs. In order to understand the gap between clinical trials and preclinical results on stroke, we discuss in detail the experimental results that served as the basis for the summarized clinical trials on immunomodulatory drugs, focusing on (i) experimental stroke models, (ii) the timing and selection of outcome measuring, (iii) alternative entry routes for leukocytes into the ischemic region, and (iv) factors affecting stroke outcome such as gender differences, ageing, comorbidities like hypertension and diabetes, obesity, tobacco, alcohol consumption and previous infections like Covid-19. We can do better for stroke treatment, especially when targeting inflammation following stroke. We need to re-think the design of stroke experimental setups, notably by (i) using clinically relevant models of stroke, (ii) including both radiological and neurological outcomes, (iii) performing long-term follow-up studies, (iv) conducting large-scale preclinical stroke trials, and (v) including stroke comorbidities in preclinical research.


Assuntos
Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/imunologia , Acidente Vascular Cerebral/fisiopatologia , Animais , Isquemia Encefálica/tratamento farmacológico , Comorbidade , Modelos Animais de Doenças , Humanos , Imunidade/imunologia , Imunidade/fisiologia , Inflamação/imunologia , Neuroproteção/imunologia , Neuroproteção/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Reperfusão/métodos , Reperfusão/tendências
5.
Antioxidants (Basel) ; 9(8)2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32708053

RESUMO

Alzheimer's disease is a chronic and irreversible pathological process that has become the most prevalent neurodegenerative disease. Currently, it is considered a multifactorial disease where oxidative stress and chronic neuroinflammation play a crucial role in its onset and development. Its characteristic neuronal loss has been related to the formation of neurofibrillary tangles mainly composed by hyperphosphorylated tau protein. Hyperphosphorylation of tau protein is related to the over-activity of GSK-3ß, a kinase that participates in several pathological mechanisms including neuroinflammation. Neuronal loss is also related to cytosolic Ca2+ homeostasis dysregulation that triggers apoptosis and free radicals production, contributing to oxidative damage and, finally, neuronal death. Under these premises, we have obtained a new family of 4,7-dihydro-2H-pyrazolo[3-b]pyridines as multitarget directed ligands showing potent antioxidant properties and able to scavenge both oxygen and nitrogen radical species, and also, with anti-inflammatory properties. Further characterization has demonstrated their capacity to inhibit GSK-3ß and to block L-type voltage dependent calcium channels. Novel derivatives have also demonstrated an interesting neuroprotective profile on in vitro models of neurodegeneration. Finally, compound 4g revokes cellular death induced by tau hyperphosphorylation in hippocampal slices by blocking reactive oxygen species (ROS) production. In conclusion, the multitarget profile exhibited by these compounds is a novel therapeutic strategy of potential interest in the search of novel treatments for Alzheimer's disease.

6.
Transl Stroke Res ; 11(3): 481-495, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31522409

RESUMO

The poor clinical relevance of experimental models of stroke contributes to the translational failure between preclinical and clinical studies testing anti-inflammatory molecules for ischemic stroke. Here, we (i) describe the time course of inflammatory responses triggered by a thromboembolic model of ischemic stroke and (ii) we examine the efficacy of two clinically tested anti-inflammatory drugs: Minocycline or anti-CD49d antibodies (tested in stroke patients as Natalizumab) administered early (1 h) or late (48 h) after stroke onset. Radiological (lesion volume) and neurological (grip test) outcomes were evaluated at 24 h and 5 days after stroke. Immune cell responses peaked 48 h after stroke onset. Myeloid cells (microglia/macrophages, dendritic cells, and neutrophils) were already increased 24 h after stroke onset, peaked at 48 h, and remained increased-although to a lesser extent-5 days after stroke onset. CD8+ and CD4+ T-lymphocytes infiltrated the ipsilateral hemisphere later on (only from 48 h). These responses occurred together with a progressive blood-brain barrier leakage at the lesion site, starting 24 h after stroke onset. Lesion volume was maximal 24-48 h after stroke onset. Minocycline reduced both lesion volume and neurological deficit only when administered early after stroke onset. The blockade of leukocyte infiltration by anti-CD49d had no impact on lesion volume or long-term neurological deficit, independently of the timing of treatment. Our data are in accordance with the results of previous clinical reports on the use of Minocycline and Natalizumab on ischemic stroke. We thus propose the use of this clinically relevant model of thromboembolic stroke with recanalization for future testing of anti-inflammatory strategies for stroke.


Assuntos
Anti-Inflamatórios/administração & dosagem , Isquemia Encefálica/imunologia , AVC Isquêmico/imunologia , Minociclina/administração & dosagem , Natalizumab/administração & dosagem , Traumatismo por Reperfusão/imunologia , Tromboembolia/imunologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/imunologia , Isquemia Encefálica/etiologia , Modelos Animais de Doenças , AVC Isquêmico/etiologia , Masculino , Camundongos , Traumatismo por Reperfusão/etiologia , Tromboembolia/complicações
7.
Pharmacol Res ; 152: 104597, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31838078

RESUMO

Neuroinflammation is increasingly associated to the onset and progression of neurodegenerative diseases. Furthermore, several lines of evidence have demonstrated the capacity of aberrant protein aggregates to activate the immune response, accelerating the advance of the disease. Compound ITH12674 is a melatonin-sulforaphane hybrid designed to exert a dual drug-prodrug mechanism of action that combines potent NRF2 induction and free radical scavenger activity. ITH12674 also showed neuroprotective properties in oxidative stress related models, that were dependant on its NRF2 inducing properties. Given the high impact of neuroinflammation in the pathogenesis of neurodegeneration, we foresaw to study the anti-inflammatory properties of ITH12674. ITH12674 reduced inflammatory markers in glial cell cultures and hippocampal tissue after LPS administration. The anti-inflammatory effect was related to inhibition of TLR4 receptors due to a direct interaction with the TLR4/MD2 complex at the hydrophobic cavity of MD2. ITH12674 is endowed with anti-inflammatory properties, that are complementary to the NRF2 inducing activity and neuroprotective properties. Thus, ITH12674 could be of potential interest for the treatment of diseases with chronic neuroinflammation.


Assuntos
Anti-Inflamatórios/farmacologia , Isotiocianatos/farmacologia , Antígeno 96 de Linfócito/metabolismo , Melatonina/análogos & derivados , Neuroglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Receptor 4 Toll-Like/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Células Cultivadas , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Interleucina-1beta/genética , Lipopolissacarídeos/farmacologia , Locomoção/efeitos dos fármacos , Masculino , Melatonina/farmacologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Moleculares , Fator 2 Relacionado a NF-E2/genética , Neuroglia/metabolismo , Ratos Sprague-Dawley , Interação Social/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética
8.
J Pineal Res ; 67(1): e12578, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30943316

RESUMO

Alterations in autophagy are increasingly being recognized in the pathogenesis of proteinopathies like Alzheimer's disease (AD). This study was conducted to evaluate whether melatonin treatment could provide beneficial effects in an Alzheimer model related to tauopathy by improving the autophagic flux and, thereby, prevent cognitive decline. The injection of AAV-hTauP301L viral vectors and treatment/injection with okadaic acid were used to achieve mouse and human ex vivo, and in vivo tau-related models. Melatonin (10 µmol/L) impeded oxidative stress, tau hyperphosphorylation, and cell death by restoring autophagy flux in the ex vivo models. In the in vivo studies, intracerebroventricular injection of AAV-hTauP301L increased oxidative stress, neuroinflammation, and tau hyperphosphorylation in the hippocampus 7 days after the injection, without inducing cognitive impairment; however, when animals were maintained for 28 days, cognitive decline was apparent. Interestingly, late melatonin treatment (10 mg/kg), starting once the alterations mentioned above were established (from day 7 to day 28), reduced oxidative stress, neuroinflammation, tau hyperphosphorylation, and caspase-3 activation; these observations correlated with restoration of the autophagy flux and memory improvement. This study highlights the importance of autophagic dysregulation in tauopathy and how administration of pharmacological doses of melatonin, once tauopathy is initiated, can restore the autophagy flux, reduce proteinopathy, and prevent cognitive decline. We therefore propose exogenous melatonin supplementation or the development of melatonin derivatives to improve autophagy flux for the treatment of proteinopathies like AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Morte Celular Autofágica/efeitos dos fármacos , Disfunção Cognitiva/tratamento farmacológico , Melatonina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/genética , Disfunção Cognitiva/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley
9.
Nat Commun ; 9(1): 3816, 2018 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-30232327

RESUMO

The ApoE4 allele is associated with increased risk of small vessel disease, which is a cause of vascular cognitive impairment. Here, we report that mice with targeted replacement (TR) of the ApoE gene with human ApoE4 have reduced neocortical cerebral blood flow compared to ApoE3-TR mice, an effect due to reduced vascular density rather than slowing of microvascular red blood cell flow. Furthermore, homeostatic mechanisms matching local delivery of blood flow to brain activity are impaired in ApoE4-TR mice. In a model of cerebral hypoperfusion, these cerebrovascular alterations exacerbate damage to the white matter of the corpus callosum and worsen cognitive dysfunction. Using 3-photon microscopy we found that the increased white matter damage is linked to an enhanced reduction of microvascular flow resulting in local hypoxia. Such alterations may be responsible for the increased susceptibility to hypoxic-ischemic lesions in the subcortical white matter of individuals carrying the ApoE4 allele.


Assuntos
Apolipoproteínas E/metabolismo , Cognição/fisiologia , Substância Branca/irrigação sanguínea , Animais , Estenose das Carótidas , Circulação Cerebrovascular , Corpo Caloso/patologia , Corpo Caloso/fisiopatologia , Marcação de Genes , Humanos , Metaloporfirinas , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Descanso , Substância Branca/patologia , Substância Branca/fisiopatologia
10.
Redox Biol ; 18: 173-180, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30029164

RESUMO

Chronic neuroinflammation is a hallmark of the onset and progression of brain proteinopathies such as Alzheimer disease (AD) and it is suspected to participate in the neurodegenerative process. Transcription factor NRF2, a master regulator of redox homeostasis, controls acute inflammation but its relevance in low-grade chronic inflammation of AD is inconclusive due to lack of good mouse models. We have addressed this question in a transgenic mouse that combines amyloidopathy and tauopathy with either wild type (AT-NRF2-WT) or NRF2-deficiency (AT-NRF2-KO). AT-NRF2-WT mice died prematurely, at around 14 months of age, due to motor deficits and a terminal spinal deformity but AT-NRF2-KO mice died roughly 2 months earlier. NRF2-deficiency correlated with exacerbated astrogliosis and microgliosis, as determined by an increase in GFAP, IBA1 and CD11b levels. The immunomodulatory molecule dimethyl fumarate (DMF), a drug already used for the treatment of multiple sclerosis whose main target is accepted to be NRF2, was tested in this preclinical model. Daily oral gavage of DMF during six weeks reduced glial and inflammatory markers and improved cognition and motor complications in the AT-NRF2-WT mice compared with the vehicle-treated animals. This study demonstrates the relevance of the inflammatory response in experimental AD, tightly regulated by NRF2 activity, and provides a new strategy to fight AD.


Assuntos
Doença de Alzheimer/genética , Encéfalo/patologia , Deleção de Genes , Inflamação/genética , Fator 2 Relacionado a NF-E2/genética , Tauopatias/genética , Doença de Alzheimer/patologia , Animais , Modelos Animais de Doenças , Feminino , Humanos , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Tauopatias/patologia
11.
J Neurochem ; 145(2): 170-182, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29315575

RESUMO

Growing evidence suggests a close relationship between Alzheimer's Disease (AD) and cerebral hypoxia. Astrocytes play a key role in brain homeostasis and disease states, while some of the earliest changes in AD occur in astrocytes. We have therefore investigated whether mutations associated with AD increase astrocyte vulnerability to ischemia. Two astroglioma cell lines derived from APPSWE /PS1A246E (APP, amyloid precursor protein; PS1, presenilin 1) transgenic mice and controls from normal mice were subjected to oxygen and glucose deprivation (OGD), an in vitro model of ischemia. Cell death was increased in the APPSWE /PS1A246E line compared to the control. Increasing extracellular calcium concentration ([Ca2+ ]) exacerbated cell death in the mutant but not in the control cells. In order to explore cellular Ca2+ homeostasis, the cells were challenged with ATP or thapsigargin and [Ca2+ ] was measured by fluorescence microscopy. Changes in cytosolic Ca2+ concentration ([Ca2+ ]c ) were potentiated in the APPSWE /PS1A246E transgenic line. Mitochondrial function was also altered in the APPSWE /PS1A246E astroglioma cells; mitochondrial membrane potential and production of reactive oxygen species were increased, while mitochondrial basal respiratory rate and ATP production were decreased compared to control astroglioma cells. These results suggest that AD mutations in astrocytes make them more sensitive to ischemia; Ca2+ dysregulation and mitochondrial dysfunction may contribute to this increased vulnerability. Our results also highlight the role of astrocyte dyshomeostasis in the pathophysiology of neurodegenerative brain disorders.


Assuntos
Doença de Alzheimer , Astrócitos , Isquemia Encefálica , Cálcio/metabolismo , Mitocôndrias/patologia , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Linhagem Celular , Glucose/deficiência , Camundongos , Camundongos Transgênicos , Mutação , Oxigênio , Presenilina-1/genética
12.
Nat Neurosci ; 21(2): 240-249, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29335605

RESUMO

A diet rich in salt is linked to an increased risk of cerebrovascular diseases and dementia, but it remains unclear how dietary salt harms the brain. We report that, in mice, excess dietary salt suppresses resting cerebral blood flow and endothelial function, leading to cognitive impairment. The effect depends on expansion of TH17 cells in the small intestine, resulting in a marked increase in plasma interleukin-17 (IL-17). Circulating IL-17, in turn, promotes endothelial dysfunction and cognitive impairment by the Rho kinase-dependent inhibitory phosphorylation of endothelial nitric oxide synthase and reduced nitric oxide production in cerebral endothelial cells. The findings reveal a new gut-brain axis linking dietary habits to cognitive impairment through a gut-initiated adaptive immune response compromising brain function via circulating IL-17. Thus, the TH17 cell-IL-17 pathway is a putative target to counter the deleterious brain effects induced by dietary salt and other diseases associated with TH17 polarization.


Assuntos
Transtornos Cerebrovasculares/induzido quimicamente , Transtornos Cognitivos/induzido quimicamente , Intestino Delgado/patologia , Cloreto de Sódio na Dieta/toxicidade , Células Th17/efeitos dos fármacos , Acetilcolina/farmacologia , Amidas/farmacologia , Animais , Anti-Hipertensivos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Polaridade Celular/efeitos dos fármacos , Circulação Cerebrovascular/efeitos dos fármacos , Transtornos Cerebrovasculares/tratamento farmacológico , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Interleucina-17/administração & dosagem , Interleucina-17/sangue , Interleucina-17/genética , Interleucina-17/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Acoplamento Neurovascular/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Piridinas/farmacologia
13.
Proc Natl Acad Sci U S A ; 114(46): 12315-12320, 2017 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-29087944

RESUMO

Ischemic injury represents the most frequent cause of death and disability, and it remains unclear why, of all body organs, the brain is most sensitive to hypoxia. In many tissues, type 4 NADPH oxidase is induced upon ischemia or hypoxia, converting oxygen to reactive oxygen species. Here, we show in mouse models of ischemia in the heart, brain, and hindlimb that only in the brain does NADPH oxidase 4 (NOX4) lead to ischemic damage. We explain this distinct cellular distribution pattern through cell-specific knockouts. Endothelial NOX4 breaks down the BBB, while neuronal NOX4 leads to neuronal autotoxicity. Vascular smooth muscle NOX4, the common denominator of ischemia within all ischemic organs, played no apparent role. The direct neuroprotective potential of pharmacological NOX4 inhibition was confirmed in an ex vivo model, free of vascular and BBB components. Our results demonstrate that the heightened sensitivity of the brain to ischemic damage is due to an organ-specific role of NOX4 in blood-brain-barrier endothelial cells and neurons. This mechanism is conserved in at least two rodents and humans, making NOX4 a prime target for a first-in-class mechanism-based, cytoprotective therapy in the unmet high medical need indication of ischemic stroke.


Assuntos
Barreira Hematoencefálica/metabolismo , Isquemia Encefálica/enzimologia , Isquemia Miocárdica/enzimologia , NADPH Oxidase 4/genética , Animais , Benzoxazóis/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Encéfalo/patologia , Isquemia Encefálica/genética , Isquemia Encefálica/patologia , Isquemia Encefálica/prevenção & controle , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Inibidores Enzimáticos/farmacologia , Feminino , Artéria Femoral/lesões , Regulação da Expressão Gênica , Membro Posterior/irrigação sanguínea , Membro Posterior/efeitos dos fármacos , Membro Posterior/metabolismo , Membro Posterior/patologia , Humanos , Masculino , Camundongos , Camundongos Knockout , Isquemia Miocárdica/genética , Isquemia Miocárdica/patologia , Isquemia Miocárdica/prevenção & controle , NADPH Oxidase 4/antagonistas & inibidores , NADPH Oxidase 4/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Especificidade de Órgãos , Pirazóis/farmacologia , Piridonas/farmacologia , Ratos , Transdução de Sinais , Triazóis/farmacologia
14.
Redox Biol ; 12: 1040-1051, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28511347

RESUMO

Mitochondria use oxygen as the final acceptor of the respiratory chain, but its incomplete reduction can also produce reactive oxygen species (ROS), especially superoxide. Acute hypoxia produces a superoxide burst in different cell types, but the triggering mechanism is still unknown. Herein, we show that complex I is involved in this superoxide burst under acute hypoxia in endothelial cells. We have also studied the possible mechanisms by which complex I could be involved in this burst, discarding reverse electron transport in complex I and the implication of PTEN-induced putative kinase 1 (PINK1). We show that complex I transition from the active to 'deactive' form is enhanced by acute hypoxia in endothelial cells and brain tissue, and we suggest that it can trigger ROS production through its Na+/H+ antiporter activity. These results highlight the role of complex I as a key actor in redox signalling in acute hypoxia.


Assuntos
Complexo I de Transporte de Elétrons/metabolismo , Células Endoteliais/metabolismo , Superóxidos/metabolismo , Animais , Bovinos , Hipóxia Celular , Células Cultivadas , Células Endoteliais/citologia , Mitocôndrias/metabolismo , Oxirredução , Proteínas Quinases/metabolismo , Transdução de Sinais
15.
Sci Rep ; 7: 45701, 2017 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-28361919

RESUMO

The formation of neurofibrillary tangles (NFTs), oxidative stress and neuroinflammation have emerged as key targets for the treatment of Alzheimer's disease (AD), the most prevalent neurodegenerative disorder. These pathological hallmarks are closely related to the over-activity of the enzyme GSK3ß and the downregulation of the defense pathway Nrf2-EpRE observed in AD patients. Herein, we report the synthesis and pharmacological evaluation of a new family of multitarget 2,4-dihydropyrano[2,3-c]pyrazoles as dual GSK3ß inhibitors and Nrf2 inducers. These compounds are able to inhibit GSK3ß and induce the Nrf2 phase II antioxidant and anti-inflammatory pathway at micromolar concentrations, showing interesting structure-activity relationships. The association of both activities has resulted in a remarkable anti-inflammatory ability with an interesting neuroprotective profile on in vitro models of neuronal death induced by oxidative stress and energy depletion and AD. Furthermore, none of the compounds exhibited in vitro neurotoxicity or hepatotoxicity and hence they had improved safety profiles compared to the known electrophilic Nrf2 inducers. In conclusion, the combination of both activities in this family of multitarget compounds confers them a notable interest for the development of lead compounds for the treatment of AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/agonistas , Fármacos Neuroprotetores/farmacologia , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Descoberta de Drogas , Humanos , Inflamação/metabolismo , Inflamação/prevenção & controle , Estresse Oxidativo , Proteínas tau/metabolismo
17.
Neuropharmacology ; 116: 110-121, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28007500

RESUMO

Compound IG20 is a newly synthesised sulphated glycolipid that promotes neuritic outgrowth and myelinisation, at the time it causes the inhibition of glial proliferation and facilitates exocytosis in chromaffin cells. Here we have shown that IG20 at 0.3-10 µM afforded neuroprotection in rat hippocampal slices stressed with veratridine, glutamate or with oxygen plus glucose deprivation followed by reoxygenation (OGD/reox). Excess production of reactive oxygen species (ROS) elicited by glutamate or ODG/reox was prevented by IG20 that also restored the depressed tissue levels of GSH and ATP in hippocampal slices subjected to OGD/reox. Furthermore, the augmented iNOS expression produced upon OGD/reox exposure was also counteracted by IG20. Additionally, the IG20 elicited neuroprotection was prevented by the presence of inhibitors of the signalling pathways Jak2/STAT3, MEK/ERK1/2, and PI3K/Akt, consistent with the ability of the compound to increase the phosphorylation of Jak2, ERK1/2, and Akt. Thus, the activation of phase II response and the Nrf2/ARE pathway could explain the antioxidant and anti-inflammatory effects and the ensuing neuroprotective actions of IG20.


Assuntos
Antioxidantes/farmacologia , Glicolipídeos/farmacologia , Hipocampo/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Antioxidantes/química , Hipóxia Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Glucose/deficiência , Ácido Glutâmico/toxicidade , Glutationa/metabolismo , Glicolipídeos/química , Hipocampo/metabolismo , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Estrutura Molecular , Fármacos Neuroprotetores/química , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Técnicas de Cultura de Tecidos , Veratridina/toxicidade
18.
Carbohydr Polym ; 157: 94-104, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-27988012

RESUMO

ITH12674 is a multitarget drug, designed to exert a dual "drug-prodrug" mechanism of action, able to induce the phase II antioxidant and anti-inflammatory response for the treatment of brain ischemia. However, its physicochemical properties limit its potential preclinical development due to its low water solubility and instability towards heat and pH variations. In order to improve its properties, we prepared the inclusion complex of ITH12674 with 2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD) by the freeze-drying method. The formation of the inclusion complex was confirmed by FT-IR spectroscopy, PXRD, DSC, 1H NMR and SEM techniques. Experimental results showed that the inclusion complex enhanced its water solubility and stability against heat, acidic and basic conditions. Furthermore, the inclusion complex, prepared in water solution, exerted the same potency to induce the phase II antioxidant response as the pure ITH12674. Thus the formation of the inclusion complex with HP-ß-CD is a very effective method to stabilize and solubilize the active compound for its future preclinical development.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina/química , Isotiocianatos/química , Melatonina/análogos & derivados , 2-Hidroxipropil-beta-Ciclodextrina/farmacologia , Varredura Diferencial de Calorimetria , Isotiocianatos/farmacologia , Melatonina/química , Melatonina/farmacologia , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , beta-Ciclodextrinas
19.
Antioxid Redox Signal ; 27(2): 93-105, 2017 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-27554853

RESUMO

AIMS: A loss in brain acetylcholine and cholinergic markers, subchronic inflammation, and impaired mitochondrial function, which lead to low-energy production and high oxidative stress, are common pathological factors in several neurodegenerative diseases (NDDs). Glial cells are important for brain homeostasis, and microglia controls the central immune response, where α7 acetylcholine nicotinic receptors (nAChR) seem to play a pivotal role; however, little is known about the effects of this receptor in metabolism. Therefore, the aim of this study was to evaluate if glial mitochondrial energetics could be regulated through α7 nAChR. RESULTS: Primary glial cultures treated with the α7 nicotinic agonist PNU282987 increased their mitochondrial mass and their mitochondrial oxygen consumption without increasing oxidative stress; these changes were abolished when nuclear erythroid 2-related factor 2 (Nrf2) was absent, heme oxygenase-1 (HO-1) was inhibited, or peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) was silenced. More specifically, microglia of animals treated intraperitoneally with the α7 nAChR agonist PNU282987 (10 mg/kg) showed a significant increase in mitochondrial mass. Interestingly, LysMcre-Hmox1Δ/Δ and PGC-1α-/- animals showed lower microglial mitochondrial levels and treatment with PNU282987 did not produce effects on mitochondrial levels. INNOVATION: Increases in microglial mitochondrial mass and metabolism can be achieved via α7 nAChR by a mechanism that implicates Nrf2, HO-1, and PGC-1α. This signaling pathway could open a new strategy for the treatment of NDDs, such as Alzheimer's, characterized by a reduction of cholinergic markers. CONCLUSION: α7 nAChR signaling increases glial mitochondrial mass, both in vitro and in vivo, via HO-1 and PCG-1α. These effects could be of potential benefit in the context of NDDs. Antioxid. Redox Signal. 27, 93-105.


Assuntos
Benzamidas/administração & dosagem , Compostos Bicíclicos com Pontes/administração & dosagem , Heme Oxigenase-1/metabolismo , Mitocôndrias/efeitos dos fármacos , Neuroglia/efeitos dos fármacos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Animais , Benzamidas/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Células Cultivadas , Injeções Intraperitoneais , Camundongos , Mitocôndrias/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Neuroglia/citologia , Neuroglia/metabolismo , Biogênese de Organelas , Ratos , Receptor Nicotínico de Acetilcolina alfa7/metabolismo
20.
Curr Top Med Chem ; 17(9): 1027-1043, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27697052

RESUMO

Alzheimer's disease (AD) is the most prevalent among the aging diseases known as neurodegenerative disorders. Drug design programs over the last two decades were mainly based on the cholinergic, the amyloid or the tau hypothesis. However, none of the new drugs have a real impact on the outcome of the disease. The complex nature of AD has led to new approaches for drug development programs, the multitarget drug design hypothesis. Based on this hypothesis, the generation of multitarget hybrid compounds from previously known active molecules has been one of the most widely used to obtain new candidates for the future treatment of AD. Here, we summarize recent developments based on the hybridization hypothesis to obtain a potential clinical candidate for AD.


Assuntos
Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Doença de Alzheimer/metabolismo , Animais , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Humanos , Estrutura Molecular , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química
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