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1.
Nat Commun ; 11(1): 4929, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33004789

RESUMO

Non-invasive, molecularly-specific, focal modulation of brain circuits with low off-target effects can lead to breakthroughs in treatments of brain disorders. We systemically inject engineered ultrasound-controllable drug carriers and subsequently apply a novel two-component Aggregation and Uncaging Focused Ultrasound Sequence (AU-FUS) at the desired targets inside the brain. The first sequence aggregates drug carriers with millimeter-precision by orders of magnitude. The second sequence uncages the carrier's cargo locally to achieve high target specificity without compromising the blood-brain barrier (BBB). Upon release from the carriers, drugs locally cross the intact BBB. We show circuit-specific manipulation of sensory signaling in motor cortex in rats by locally concentrating and releasing a GABAA receptor agonist from ultrasound-controlled carriers. Our approach uses orders of magnitude (1300x) less drug than is otherwise required by systemic injection and requires very low ultrasound pressures (20-fold below FDA safety limits for diagnostic imaging). We show that the BBB remains intact using passive cavitation detection (PCD), MRI-contrast agents and, importantly, also by sensitive fluorescent dye extravasation and immunohistochemistry.


Assuntos
Barreira Hematoencefálica/metabolismo , Encefalopatias/tratamento farmacológico , Portadores de Fármacos/efeitos da radiação , Agonistas de Receptores de GABA-A/administração & dosagem , Ultrassonografia de Intervenção/métodos , Animais , Barreira Hematoencefálica/diagnóstico por imagem , Barreira Hematoencefálica/efeitos da radiação , Relação Dose-Resposta à Radiação , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Feminino , Agonistas de Receptores de GABA-A/farmacocinética , Humanos , Imagem por Ressonância Magnética , Modelos Animais , Muscimol/administração & dosagem , Muscimol/farmacocinética , Ratos , Técnicas Estereotáxicas , Ondas Ultrassônicas
2.
Yakugaku Zasshi ; 140(10): 1235-1242, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32999202

RESUMO

The central nervous system (CNS) is segregated from the circulating blood and peripheral tissues by endothelial and epithelial barriers. To overcome refractory CNS diseases, it is important to understand the membrane transport systems of drugs and the endogenous compounds that relate to the pathogenesis of CNS diseases at these barriers. The endothelial barrier in the brain is the blood-brain barrier (BBB). Our studies clarified the efflux transport of prostaglandin E2 (PGE2), a modulator of neural excitation and inflammatory responses, across the BBB via plasma membrane transporters such as organic anion transporter 3 (Oat3) and multidrug resistance-associated protein 4 (Mrp4). This efflux transport was attenuated by peripheral inflammation or cerebral treatment with neuroexcitatory l-glutamate, suggesting that BBB-mediated PGE2 elimination was altered under several pathological conditions. We also examined excitatory amino acid transporter (EAAT) 1 and 3 as l-glutamate efflux transporters of the inner blood-retinal barrier (BRB) and blood-cerebrospinal barrier. It was considered that these efflux membrane transporters participated in the homeostasis of neuroexcitatory and neuroinflammatory responses in the brain and retina. Moreover, we identified connexin 43 (Cx43) hemichannels as a new membrane transport system that is activated under pathological conditions and recognizes several monocarboxylate drugs, such as valproate. As it is expected that the action of these membrane transporters across the CNS barriers is of great importance in understanding the pathology of various neuroexcitatory diseases, our studies should contribute to the establishment of therapeutic strategies for refractory CNS diseases.


Assuntos
Transporte Biológico , Barreira Hematoencefálica/metabolismo , Barreira Hematorretiniana/metabolismo , Encéfalo/metabolismo , Doenças do Sistema Nervoso Central/etiologia , Doenças do Sistema Nervoso Central/metabolismo , Desenvolvimento de Medicamentos , Proteínas de Membrana Transportadoras/metabolismo , Retina/metabolismo , Animais , Doenças do Sistema Nervoso Central/tratamento farmacológico , Conexina 43/metabolismo , Dinoprostona/metabolismo , Transportador 1 de Aminoácido Excitatório/metabolismo , Ácido Glutâmico/metabolismo , Humanos , Camundongos , Terapia de Alvo Molecular , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo
3.
Front Immunol ; 11: 565521, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013930

RESUMO

Neurological disorders caused by neuroviral infections are an obvious pathogenic manifestation. However, non-neurotropic viruses or peripheral viral infections pose a considerable challenge as their neuropathological manifestations do not emerge because of primary infection. Their secondary or bystander pathologies develop much later, like a syndrome, during and after the recovery of patients from the primary disease. Massive inflammation caused by peripheral viral infections can trigger multiple neurological anomalies. These neurological damages may range from a general cognitive and motor dysfunction up to a wide spectrum of CNS anomalies, such as Acute Necrotizing Hemorrhagic Encephalopathy, Guillain-Barré syndrome, Encephalitis, Meningitis, anxiety, and other audio-visual disabilities. Peripheral viruses like Measles virus, Enteroviruses, Influenza viruses (HIN1 series), SARS-CoV-1, MERS-CoV, and, recently, SARS-CoV-2 are reported to cause various neurological manifestations in patients and are proven to be neuropathogenic even in cellular and animal model systems. This review presents a comprehensive picture of CNS susceptibilities toward these peripheral viral infections and explains some common underlying themes of their neuropathology in the human brain.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/complicações , Infecções por Coronavirus/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Inflamação Neurogênica/complicações , Inflamação Neurogênica/imunologia , Pneumonia Viral/complicações , Pneumonia Viral/imunologia , Vírus da SARS/imunologia , Síndrome Respiratória Aguda Grave/complicações , Animais , Barreira Hematoencefálica/imunologia , Barreira Hematoencefálica/virologia , Infecções por Coronavirus/virologia , Citocinas/sangue , Modelos Animais de Doenças , Humanos , Microglia/imunologia , Microglia/virologia , Inflamação Neurogênica/virologia , Pandemias , Pneumonia Viral/virologia , Síndrome Respiratória Aguda Grave/imunologia , Síndrome Respiratória Aguda Grave/virologia
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 5033-5036, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019117

RESUMO

This article presents a method to plan BloodBrain Barrier (BBB) disruption with Focused Ultrasound, under neuronavigated robotic assistance. Robotic and acoustic constraints are defined to estimate brain target accessibility. The relevance of the proposed framework is illustrated in specific brain target examples.


Assuntos
Barreira Hematoencefálica , Robótica , Transporte Biológico , Barreira Hematoencefálica/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Ultrassonografia
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2270-2273, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018460

RESUMO

Iron plays important roles in healthy brain but altered homeostasis and concentration have been correlated to aging and neurodegenerative diseases. Iron enters the central nervous system by crossing the brain barrier systems: the Blood- Brain Barrier separating blood and brain and the Blood-Cerebrospinal Fluid Barrier (BCSFB) between blood and CSF, which is in contact with the brain by far less selective barriers. Herein, we develop a two-compartmental model for the BCSFB, based on first-order ordinary differential equations, performing numerical simulations and sensitivity analysis. Furthermore, as input parameters of the model, experimental data from patients affected by Alzheimer's disease, frontotemporal dementia, mild cognitive impairment and matched neurological controls were used, with the aim of investigating the differences between physiological and pathological conditions in the regulation of iron passage between blood and CSF which can be possibly targeted by therapy.


Assuntos
Doenças Neurodegenerativas , Barreira Hematoencefálica , Encéfalo , Humanos , Ferro , Modelos Teóricos
6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3331-3334, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018717

RESUMO

Blood-brain barrier (BBB) imposes a major obstacle for entry of therapeutics to brain. In vitro BBB models that can provide reliable prediction of therapeutics' ability to cross BBB are thus, critical for the advancement of brain therapeutics. Towards the development of an improved BBB model, here we studied the individual and combinatorial effect of few different culture conditions on the quality of the commonly used trans-well BBB model. Specifically, we investigated how the addition of (i) astrocyte co-culture, (ii) astrocyte-conditioned media (ACM), and (iii) astrocyte co-culture along with ACM, affects the characteristics of BBB. The resultant BBB models were characterized for trans-endothelial electrical resistance (TEER), permeability, and expression of a tight-junction protein ZO-1. We found that addition of ACM and astrocytes, individually, had similar impact on BBB's TEER, increasing it by ~2 fold. Interestingly, the presence of both astrocytes and ACM had a significantly greater impact on TEER and increased it by ~3 fold. Addition of ACM, with and without astrocyte co-culture, led to a reduction in permeability of this BBB model. Moreover, addition of ACM and astrocyte co-culture, both individually and in combination, led to a noticeable increase in ZO-1 expression in the BBB endothelial cells. These findings provide a new approach for further improvement of the commonly used trans-well BBB system.


Assuntos
Barreira Hematoencefálica , Células Endoteliais , Astrócitos , Encéfalo , Permeabilidade Capilar
7.
Nat Commun ; 11(1): 4413, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887883

RESUMO

The molecular signatures of cells in the brain have been revealed in unprecedented detail, yet the ageing-associated genome-wide expression changes that may contribute to neurovascular dysfunction in neurodegenerative diseases remain elusive. Here, we report zonation-dependent transcriptomic changes in aged mouse brain endothelial cells (ECs), which prominently implicate altered immune/cytokine signaling in ECs of all vascular segments, and functional changes impacting the blood-brain barrier (BBB) and glucose/energy metabolism especially in capillary ECs (capECs). An overrepresentation of Alzheimer disease (AD) GWAS genes is evident among the human orthologs of the differentially expressed genes of aged capECs, while comparative analysis revealed a subset of concordantly downregulated, functionally important genes in human AD brains. Treatment with exenatide, a glucagon-like peptide-1 receptor agonist, strongly reverses aged mouse brain EC transcriptomic changes and BBB leakage, with associated attenuation of microglial priming. We thus revealed transcriptomic alterations underlying brain EC ageing that are complex yet pharmacologically reversible.


Assuntos
Envelhecimento/patologia , Barreira Hematoencefálica , Encéfalo/fisiopatologia , Células Endoteliais/metabolismo , Exenatida/farmacologia , Doença de Alzheimer/fisiopatologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiopatologia , Capilares/metabolismo , Células Cultivadas , Humanos , Camundongos , Microglia/efeitos dos fármacos , Doenças Neurodegenerativas/fisiopatologia , Transcriptoma/efeitos dos fármacos
8.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(7): 1018-1022, 2020 Jul 30.
Artigo em Chinês | MEDLINE | ID: mdl-32895167

RESUMO

OBJECTIVE: To investigate the effects of blocking the activation of ERK pathway on the expression of matrix metalloproteinase-9 (MMP-9) and the formation of cerebral edema in SD rats after brain injury. METHODS: Ninety SD rats were randomly divided into 3 equal groups, including a sham-operated group, modified Feeney's traumatic brain injury model group, and ERK inhibition group where the ERK inhibitor SCH772984 (500 µg/kg) was injected via the femoral vein 15 min before brain trauma. At 2 h and 2 days after brain trauma, the permeability of blood-brain barrier was assessed by Evans blue method, the water content of the brain tissue was determined, and the phosphorylation level of ERK and the expression level of MMP-9 mRNA and protein were measured by RT-PCR and Western blotting. RESULTS: Compared with the sham-operated group, the rats with brain trauma exhibited significantly increased level of ERK phosphorylation at 2 h and significantly increased expression of MMP-9 mRNA and protein 2 days after the injury (P < 0.01). Treatment with the ERK inhibitor significantly decreased the phosphorylation level of ERK after the injury (P < 0.01), suppressed over-expression of MMP-9 mRNA and protein 2 days after the injury (P < 0.01). The permeability of blood-brain barrier increased significantly 2 h after brain trauma (P < 0.05) and increased further at 2 days (P < 0.01); the water content of the brain did not change significantly at 2 h (P > 0.05) but increased significantly 2 d after the injury (P < 0.01). Treatment with the ERK inhibitor significantly lowered the permeability of blood-brain barrier and brain water content after brain trauma (P < 0.01). CONCLUSIONS: Blocking the activation of ERK pathway significantly reduced the over-expression of MMP-9 and alleviates the damage of blood-brain barrier and traumatic brain edema, suggesting that ERK signaling pathway plays an important role in traumatic brain edema by regulating the expression of MMP-9.


Assuntos
Edema Encefálico , Lesões Encefálicas Traumáticas , Sistema de Sinalização das MAP Quinases , Animais , Barreira Hematoencefálica , Metaloproteinase 9 da Matriz , Ratos , Ratos Sprague-Dawley
9.
Fluids Barriers CNS ; 17(1): 55, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32912226

RESUMO

Human coronaviruses are highly pathogenic viruses that pose a serious threat to human health. Examples include the severe acute respiratory syndrome outbreak of 2003 (SARS-CoV-1), the Middle East Respiratory Syndrome (MERS-CoV) outbreak of 2012, and the current SARS-CoV-2 (COVID-19) pandemic. Herein, we review the neurological manifestations of coronaviruses and discuss the potential pathogenic role of blood-brain barrier dysfunction. We present the hypothesis that pre-existing vascular damage (due to aging, cardiovascular disease, diabetes, hypertension or other conditions) facilitates infiltration of the virus into the central nervous system (CNS), increasing neuro-inflammation and the likelihood of neurological symptoms. We also discuss the role of a neuroinflammatory cytokine profile in both blood-brain barrier dysfunction and macrovascular disease (e.g. ischemic stroke and thromboembolism). Future studies are needed to better understand the involvement of the microvasculature in coronavirus neuropathology, and to test the diagnostic potential of minimally-invasive screening tools (e.g. serum biomarkers, fluorescein retinal angiography and dynamic-contrast MRI).


Assuntos
Barreira Hematoencefálica/fisiopatologia , Infecções por Coronavirus/fisiopatologia , Inflamação/fisiopatologia , Microvasos/fisiopatologia , Doenças do Sistema Nervoso/fisiopatologia , Pneumonia Viral/fisiopatologia , Betacoronavirus , Barreira Hematoencefálica/imunologia , Barreira Hematoencefálica/virologia , Doenças Cardiovasculares/fisiopatologia , Infecções por Coronavirus/imunologia , Citocinas/imunologia , Diabetes Mellitus/fisiopatologia , Encefalite/imunologia , Encefalite/fisiopatologia , Humanos , Inflamação/imunologia , Microvasos/imunologia , Doenças do Sistema Nervoso/imunologia , Pandemias , Pneumonia Viral/imunologia , Convulsões/imunologia , Convulsões/fisiopatologia , Acidente Vascular Cerebral/imunologia , Acidente Vascular Cerebral/fisiopatologia , Tromboembolia/imunologia , Tromboembolia/fisiopatologia
10.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 34(9): 1163-1169, 2020 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-32929911

RESUMO

Objective: To explore the feasibility and mechanism of inhibiting miR-429 to improve the permeability of the blood spinal cord barrier (BSCB) in vitro, and provide a new gene therapy target for enhancing the spinal cord microenvironment. Methods: First, the immortalized human brain microvascular endothelial cell line (hCMEC/D3) was transfected with the anti-miR-429 antagonist (antagomiR-429) and its negative control (antagomiR-429-NC), respectively. The miR-429 expression of hCMEC/D3 cells was observed by fluorescence microscopy and real-time fluorescence quantitative PCR to verify the transfection efficiency of antagomiR-429. Then the effect of miR-429 on BSCB permeability was observed in vitro. The experiment was divided into 4 groups. The blank control group (group A) was constructed of normal hCMEC/D3 cells and Ha-sc cells to prepare the BSCB model, the hypoxia-induced group (group B), the hypoxia-induced+antagomiR-429-NC group (group C), and the hypoxia-induced+antagomiR-429 group (group D) were constructed of normal, antagomiR-429-NC transfected, and antagomiR-429 transfected hCMEC/D3 cells and Ha-sc cells to prepare the BSCB models and hypoxia treatment for 12 hours. The permeability of BSCB in vitro was measured by horseradish peroxidase (HRP) permeability. Real-time fluorescence quantitative PCR, Western blot, and immunofluorescence staining were used to observe the expressions of ZO-1, Occludin, and Claudin-5. Results: The antagomiR-429 and antagomiR-429-NC were successfully transfected into hCMEC/D3 cells under a fluorescence microscope, and the transfection efficiency was about 90%. Real-time fluorescence quantitative PCR results showed that the relative expression of miR-429 in antagomiR-429 group was 0.109±0.013, which was significantly lower than that of antagomiR-429-NC group (0.956±0.004, P<0.05). HRP permeability measurement, real-time fluorescence quantitative PCR, and Western blot results showed that the HRP permeability of groups B and C were significantly higher than those of groups A and D ( P<0.05), and the relative expressions of ZO-1, Occludin, and Claudin-5 proteins and mRNAs were significantly lower in groups B and C than in groups A and D ( P<0.05) and in group D than in group A ( P<0.05); there was no significant difference between groups B and C ( P>0.05). Immunofluorescence staining showed that the immunofluorescence of ZO-1, Occudin, and Claudin-5 at the cell membrane boundary in group D were stronger than those in groups B and C, but not as strong as that in group A. Conclusion: Inhibition of miR-429 expression can promote the expressions of ZO-1, Occludin, and Claudin-5 proteins in microvascular endothelial cells, thereby improving the increased permeability of BSCB due to hypoxia.


Assuntos
Células Endoteliais , MicroRNAs , Barreira Hematoencefálica , Hipóxia Celular , Claudina-5 , Humanos , Ocludina , Permeabilidade , Medula Espinal , Proteína da Zônula de Oclusão-1
11.
Psychiatr Danub ; 32(Suppl 1): 93-104, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32890371

RESUMO

Mechanisms of cortical psychoses are approached by complementing big data-driven genetics and imaging with a putatively subverted neurovascular "reverse plumbing" by arteries. The "cortical spread" of grey matter loss in schizophrenia and the mid-pericallosal "congestion" in fMRI of periodic catatonia - treatable electromagnetically along arteries - are interpreted in terms of the fastest interstitial outflow through the Cerebral IntraMural Reverse Arterial Flow-engine (CIMURAF, Treviranus 2018-19) draining "waste" via arterio-adventitial lymphatics to the neck. Such repetitively sliding segments of CIMURAF are wrung downstream by muscles likely steered by the neurovascular pterygopalatine ganglion. At the pericallosal artery, along its ideal long straight segment, this likely happens diverging from the mid-callosum towards the front and the back. In the case of a convergent inversion a mid-callosal clash will result, which is observable in psychoses as a mid-callosal high-flow-spot simultaneously with hyper-perfusions of branches and "backwatering" of pial vessels with reactive waste - till date interpreted psycho-mathematically. CIMURAF might also accelerate the perivascular intrusion of MCs by flushing autocrine signals (of which electro-magnetism moves the dipoles) through a putative periadventitial counter-current. Psychoses plausible occur through tryptase-mediated attacks operated by mast cells against oligodendrocytes' cytoskeleton (Medic 2009) and probably via complement-4 (Schizophrenia WG, 2014) against neurons. Usually MCs are essential long-lived "orchestrators" of homeostases and immune or barrier defences interacting with nerves, immunocytes, organs, and routes. MCs after somatic programming as to "destination & destiny" (Treviranus 2017a, 6.2., 2018) rapidly intrude also into the brain's parenchyma, first within the lymphatics and then putatively by crossing-over to extraluminal arterial routes. MCs transverse the BBBs, while macrophages only trespass in "disease" (Faraco et al. 2017). Both can be "subverted" by a list of microbes (and putatively blown up by COVID-19 within walls). Enuresis and MCs' reactions to clozapine add to the interactive support from (epi-)genetics and imaging.


Assuntos
Mastócitos/imunologia , Transtornos Psicóticos/imunologia , Betacoronavirus , Barreira Hematoencefálica/imunologia , Infecções por Coronavirus , Gânglios , Humanos , Mastócitos/patologia , Pandemias , Pneumonia Viral
12.
PLoS One ; 15(9): e0238238, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881880

RESUMO

The prognosis for patients with glioblastoma (GB) remains grim. Concurrent temozolomide (TMZ) radiation-the cornerstone of glioma control-extends the overall median survival of GB patients by only a few months over radiotherapy alone. While these survival gains could be partly attributed to radiosensitization, this benefit is greatly minimized in tumors expressing O6-methylguanine DNA methyltransferase (MGMT), which specifically reverses O6-methylguanine lesions. Theoretically, non-O6-methylguanine lesions (i.e., the N-methylpurine adducts), which represent up to 90% of TMZ-generated DNA adducts, could also contribute to radiosensitization. Unfortunately, at concentrations attainable in clinical practice, the alkylation capacity of TMZ cannot overwhelm the repair of N-methylpurine adducts to efficiently exploit these lesions. The current therapeutic application of TMZ therefore faces two main obstacles: (i) the stochastic presence of MGMT and (ii) a blunted radiosensitization potential at physiologic concentrations. To circumvent these limitations, we are developing a novel molecule called NEO212-a derivatization of TMZ generated by coupling TMZ to perillyl alcohol. Based on gas chromatography/mass spectrometry and high-performance liquid chromatography analyses, we determined that NEO212 had greater tumor cell uptake than TMZ. In mouse models, NEO212 was more efficient than TMZ at crossing the blood-brain barrier, preferentially accumulating in tumoral over normal brain tissue. Moreover, in vitro analyses with GB cell lines, including TMZ-resistant isogenic variants, revealed more potent cytotoxic and radiosensitizing activities for NEO212 at physiologic concentrations. Mechanistically, these advantages of NEO212 over TMZ could be attributed to its enhanced tumor uptake presumably leading to more extensive DNA alkylation at equivalent dosages which, ultimately, allows for N-methylpurine lesions to be better exploited for radiosensitization. This effect cannot be achieved with TMZ at clinically relevant concentrations and is independent of MGMT. Our findings establish NEO212 as a superior radiosensitizer and a potentially better alternative to TMZ for newly diagnosed GB patients, irrespective of their MGMT status.


Assuntos
Dacarbazina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , Glioma/tratamento farmacológico , Radiossensibilizantes/uso terapêutico , Temozolomida/uso terapêutico , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Dacarbazina/análise , Dacarbazina/metabolismo , Dacarbazina/farmacologia , Dacarbazina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Cromatografia Gasosa-Espectrometria de Massas , Glioma/patologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , O(6)-Metilguanina-DNA Metiltransferase/metabolismo , Radiossensibilizantes/análise , Radiossensibilizantes/metabolismo , Radiossensibilizantes/farmacologia , Temozolomida/análise , Temozolomida/metabolismo , Temozolomida/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
13.
PLoS One ; 15(9): e0238301, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881954

RESUMO

BACKGROUND: Neuromyelitis optica spectrum disorders (NMOSD) is a primary astrocytopathy driven by antibodies directed against the aquaporin-4 water channel located at the end-feet of the astrocyte. Although blood-brain barrier (BBB) breakdown is considered one of the key steps for the development and lesion formation, little is known about the molecular mechanisms involved. The aim of the study was to evaluate the effect of human immunoglobulins from NMOSD patients (NMO-IgG) on BBB properties. METHODS: Freshly isolated brain microvessels (IBMs) from rat brains were used as a study model. At first, analysis of the secretome profile from IBMs exposed to purified NMO-IgG, to healthy donor IgG (Control-IgG), or non-treated, was performed. Second, tight junction (TJ) proteins expression in fresh IBMs and primary cultures of brain microvascular endothelial cells (BMEC) was analysed by Western blotting (Wb) after exposition to NMO-IgG and Control-IgG. Finally, functional BBB properties were investigated evaluating the presence of rat-IgG in tissue lysate from brain using Wb in the rat-model, and the passage of NMO-IgG and sucrose in a bicameral model. RESULTS: We found that NMO-IgG induces functional and morphological BBB changes, including: 1) increase of pro-inflammatory cytokines production (CXCL-10 [IP-10], IL-6, IL-1RA, IL-1ß and CXCL-3) in IBMs when exposed to NMO-IgG; 2) decrease of Claudin-5 levels by 25.6% after treatment of fresh IBMs by NMO-IgG compared to Control-IgG (p = 0.002), and similarly, decrease of Claudin-5 by at least 20% when BMEC were cultured with NMO-IgG from five different patients; 3) a higher level of rat-IgG accumulated in periventricular regions of NMO-rats compared to Control-rats and an increase in the permeability of BBB after NMO-IgG treatment in the bicameral model. CONCLUSION: Human NMO-IgG induces both structural and functional alterations of BBB properties, suggesting a direct role of NMO-IgG on modulation of BBB permeability in NMOSD.


Assuntos
Aquaporina 4/imunologia , Barreira Hematoencefálica/metabolismo , Imunoglobulina G/farmacologia , Neuromielite Óptica/patologia , Permeabilidade/efeitos dos fármacos , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Células Cultivadas , Quimiocinas/metabolismo , Claudina-5/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Imunoglobulina G/isolamento & purificação , Microvasos/citologia , Microvasos/metabolismo , Neuromielite Óptica/metabolismo , Ratos
14.
Nat Commun ; 11(1): 4790, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32963242

RESUMO

Preventing aggregation of amyloid beta (Aß) peptides is a promising strategy for the treatment of Alzheimer's disease (AD), and gold nanoparticles have previously been explored as a potential anti-Aß therapeutics. Here we design and prepare 3.3 nm L- and D-glutathione stabilized gold nanoparticles (denoted as L3.3 and D3.3, respectively). Both chiral nanoparticles are able to inhibit aggregation of Aß42 and cross the blood-brain barrier (BBB) following intravenous administration without noticeable toxicity. D3.3 possesses a larger binding affinity to Aß42 and higher brain biodistribution compared with its enantiomer L3.3, giving rise to stronger inhibition of Aß42 fibrillation and better rescue of behavioral impairments in AD model mice. This conjugation of a small nanoparticle with chiral recognition moiety provides a potential therapeutic approach for AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/efeitos dos fármacos , Ouro/farmacologia , Transtornos da Memória/tratamento farmacológico , Nanopartículas Metálicas/química , Fragmentos de Peptídeos/efeitos dos fármacos , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Masculino , Transtornos da Memória/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Fragmentos de Peptídeos/metabolismo , Estereoisomerismo
15.
PLoS One ; 15(9): e0238397, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32966285

RESUMO

The development of drugs targeting the brain still faces a high failure rate. One of the reasons is a lack of quantitative understanding of the complex processes that govern the pharmacokinetics (PK) of a drug within the brain. While a number of models on drug distribution into and within the brain is available, none of these addresses the combination of factors that affect local drug concentrations in brain extracellular fluid (brain ECF). Here, we develop a 3D brain unit model, which builds on our previous proof-of-concept 2D brain unit model, to understand the factors that govern local unbound and bound drug PK within the brain. The 3D brain unit is a cube, in which the brain capillaries surround the brain ECF. Drug concentration-time profiles are described in both a blood-plasma-domain and a brain-ECF-domain by a set of differential equations. The model includes descriptions of blood plasma PK, transport through the blood-brain barrier (BBB), by passive transport via paracellular and transcellular routes, and by active transport, and drug binding kinetics. The impact of all these factors on ultimate local brain ECF unbound and bound drug concentrations is assessed. In this article we show that all the above mentioned factors affect brain ECF PK in an interdependent manner. This indicates that for a quantitative understanding of local drug concentrations within the brain ECF, interdependencies of all transport and binding processes should be understood. To that end, the 3D brain unit model is an excellent tool, and can be used to build a larger network of 3D brain units, in which the properties for each unit can be defined independently to reflect local differences in characteristics of the brain.


Assuntos
Encéfalo/metabolismo , Modelos Neurológicos , Preparações Farmacêuticas/metabolismo , Animais , Transporte Biológico Ativo , Velocidade do Fluxo Sanguíneo , Barreira Hematoencefálica/metabolismo , Encéfalo/anatomia & histologia , Encéfalo/irrigação sanguínea , Líquido Extracelular/metabolismo , Humanos , Conceitos Matemáticos , Preparações Farmacêuticas/sangue , Farmacocinética , Ratos , Distribuição Tecidual
16.
Am J Chin Med ; 48(6): 1331-1351, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32907361

RESUMO

Panax notoginseng is the most widely used Chinese medicinal herb for the prevention and treatment of ischemic diseases. Its main active ingredients are saponins, including ginsenoside Rb1, ginsenoside Rg1, and notoginsenoside R1, among others. This review provides an up-to-date overview on the pharmacological roles of P. notoginseng constituents in cerebral ischemia. The saponins of P. notoginseng induce a variety of pharmacological effects in the multiscale mechanisms of cerebral ischemic pathophysiology, including anti-inflammatory activity, reduction of oxidative stress, anti-apoptosis, inhibition of amino acid excitotoxicity, reduction of intracellular calcium overload, protection of mitochondria, repairing the blood-brain barrier, and facilitation of cell regeneration. Regarding cell regeneration, P. notoginseng not only promotes the proliferation and differentiation of neural stem cells, but also protects neurons, endothelial cells and astrocytes in cerebral ischemia. In conclusion, P. notoginseng may treat cerebrovascular diseases through multiple pharmacological effects, and the most critical ones need further investigation.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Ginsenosídeos/farmacologia , Ginsenosídeos/uso terapêutico , Panax notoginseng/química , Fitoterapia , Saponinas/farmacologia , Saponinas/uso terapêutico , Aminoácidos/toxicidade , Animais , Anti-Inflamatórios , Antioxidantes , Apoptose/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Isquemia Encefálica/etiologia , Isquemia Encefálica/patologia , Isquemia Encefálica/prevenção & controle , Cálcio/metabolismo , Autorrenovação Celular/efeitos dos fármacos , Depuradores de Radicais Livres , Ginsenosídeos/isolamento & purificação , Humanos , Fármacos Neuroprotetores , Estresse Oxidativo/efeitos dos fármacos , Saponinas/isolamento & purificação
17.
PLoS One ; 15(9): e0236611, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32941446

RESUMO

Treatment of diseases that affect the CNS by gene therapy requires delivery of oligonucleotides to target cells within the brain. As the blood brain barrier prevents movement of large biomolecules, current approaches involve direct injection of the oligonucleotides, which is invasive and may have only a localised effect. The aim of this study was to investigate the potential of 2 nm galactose-coated gold nanoparticles (NP-Gal) as a delivery system of oligonucleotides across brain endothelium. DNA oligonucleotides of different types were attached to NP-Gal by the place exchange reaction and were characterised by EMSA (electrophoretic mobility shift assay). Several nanoparticle formulations were created, with single- or double-stranded (20nt or 40nt) DNA oligonucleotides, or with different amounts of DNA attached to the carriers. These nanocarriers were applied to transwell cultures of human brain endothelium in vitro (hCMEC/D3 cell-line) or to a 3D-hydrogel model of the blood-brain barrier including astrocytes. Transfer rates were measured by quantitative electron microscopy for the nanoparticles and qPCR for DNA. Despite the increase in nanoparticle size caused by attachment of oligonucleotides to the NP-Gal carrier, the rates of endocytosis and transcytosis of nanoparticles were both considerably increased when they carried an oligonucleotide cargo. Carriers with 40nt dsDNA were most efficient, accumulating in vesicles, in the cytosol and beneath the basal membrane of the endothelium. The oligonucleotide cargo remained attached to the nanocarriers during transcytosis and the transport rate across the endothelial cells was increased at least 50fold compared with free DNA. The nanoparticles entered the extracellular matrix and were taken up by the astrocytes in biologically functional amounts. Attachment of DNA confers a strong negative charge to the nanoparticles which may explain the enhanced binding to the endothelium and transcytosis by both vesicular transport and the transmembrane/cytosol pathway. These gold nanoparticles have the potential to transport therapeutic amounts of nucleic acids into the CNS.


Assuntos
Barreira Hematoencefálica/metabolismo , Células Endoteliais/metabolismo , Nanopartículas Metálicas/química , Oligodesoxirribonucleotídeos/metabolismo , Astrócitos/metabolismo , Linhagem Celular , Células Cultivadas , Galactose/química , Ouro/química , Humanos , Oligodesoxirribonucleotídeos/administração & dosagem
18.
J Biomed Nanotechnol ; 16(5): 626-639, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32919483

RESUMO

Glial cell line derived neurotropic factor (GDNF) plays a crucial role in the development and maintenance of glial cells, serotonergic and dopaminergic neurons. A positively therapeutic effect has been demonstrated on some animal neurodegenerative diseases. However, the inability to deliver the protein across blood brain barrier (BBB) into damaged brain region limits its clinical application. Here, we developed GDNF-loaded microbubbles (MBs) and achieved a local and precise delivery of GDNF into the brain through MRI-guided focused ultrasound-induced BBB disruption. To demonstrate the therapeutic effect, rat depression model was developed by chronic mild stress treatment. Typical depression behaviors were confirmed. MRI-guided focused ultrasound was used to irradiate the GDNF-loaded MBs. Obvious BBB opening was observed in the treated rat brains and a significant higher GDNF concentration was detected in the ultrasound-treated brain tissues. Behavioral tests demonstrated the increased GDNF could reverse the depressive-like behaviors induced by chronic mild stress, improve the expression of 5-HT 1B receptor and the protein p11, and increase the number of 5-HT or TPH2 immunoreactive neurons. In conclusion, our study provided an effective approach to deliver GDNF proteins into brain to treat rat depression through MRI-guided focused ultrasound-induced destruction of blood-brain barrier.


Assuntos
Barreira Hematoencefálica , Depressão , Neuroglia , Animais , Encéfalo , Linhagem Celular , Imagem por Ressonância Magnética , Ratos
19.
Artigo em Inglês | MEDLINE | ID: mdl-32978291

RESUMO

OBJECTIVE: To investigate the pathophysiologic mechanism of encephalopathy and prolonged comatose or stuporous state in severally ill patients with coronavirus disease 2019 (COVID-19). METHODS: Eight COVID-19 patients with signs of encephalopathy were tested for antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the serum and CSF using a Food and Drug Administration-approved and independently validated ELISA. Blood-brain barrier (BBB) integrity and immunoglobulin G (IgG) intrathecal synthesis were further tested using albumin and IgG indices. The CSF was also tested for autoimmune encephalitis antibodies and 14-3-3, a marker of ongoing neurodegeneration. RESULTS: All patients had anti-SARS-CoV-2 antibodies in their CSF, and 4 of 8 patients had high titers, comparable to high serum values. One patient had anti-SARS-CoV-2 IgG intrathecal synthesis, and 3 others had disruption of the blood-brain barrier. The CSF in 4 patients was positive for 14-3-3-protein suggesting ongoing neurodegeneration. In all patients, the CSF was negative for autoimmune encephalitis antibodies and SARS-CoV-2 by PCR. None of the patients, apart from persistent encephalopathic signs, had any focal neurologic signs or history or specific neurologic disease. CONCLUSIONS: High-titer anti-SARS-CoV-2 antibodies were detected in the CSF of comatose or encephalopathic patients demonstrating intrathecal IgG synthesis or BBB disruption. A disrupted BBB may facilitate the entry of cytokines and inflammatory mediators into the CNS enhancing neuroinflammation and neurodegeneration. The observations highlight the need for prospective CSF studies to determine the pathogenic role of anti-SARS-CoV-2 antibodies and identify early therapeutic interventions.


Assuntos
Autoanticorpos/líquido cefalorraquidiano , Betacoronavirus/isolamento & purificação , Barreira Hematoencefálica/metabolismo , Coma/líquido cefalorraquidiano , Infecções por Coronavirus/líquido cefalorraquidiano , Doenças do Sistema Nervoso/líquido cefalorraquidiano , Pneumonia Viral/líquido cefalorraquidiano , Estupor/líquido cefalorraquidiano , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/líquido cefalorraquidiano , Coma/diagnóstico , Infecções por Coronavirus/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/diagnóstico , Pandemias , Pneumonia Viral/diagnóstico , Estupor/diagnóstico , Resultado do Tratamento
20.
Pharm Res ; 37(10): 194, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32918191

RESUMO

PURPOSE: We characterized three canine P-gp (cP-gp) deficient MDCKII cell lines. Their relevance for identifying efflux transporter substrates and predicting limitation of brain penetration were evaluated. In addition, we discuss how compound selection can be done in drug discovery by using these cell systems. METHOD: hMDR1, hBCRP-transfected, and non-transfected MDCKII ZFN cells (all with knock-down of endogenous cP-gp) were used for measuring permeability and efflux ratios for substrates. The compounds were also tested in MDR1_Caco-2 and BCRP_Caco-2, each with a double knock-out of BCRP/MRP2 or MDR1/MRP2 transporters respectively. Efflux results were compared between the MDCK and Caco-2 models. Furthermore, in vitro MDR1_ZFN efflux data were correlated with in vivo unbound drug brain-to-plasma partition coefficient (Kp,uu). RESULTS: MDR1 and BCRP substrates are correctly classified and robust transporter affinities with control substrates are shown. Cell passage mildly influenced mRNA levels of transfected transporters, but the transporter activity was proven stable for several years. The MDCK and Caco-2 models were in high consensus classifying same efflux substrates. Approx. 80% of enlisted substances were correctly predicted with the MDR1_ZFN model for brain penetration. CONCLUSION: cP-gp deficient MDCKII ZFN models are reliable tools to identify MDR1 and BCRP substrates and useful for predicting efflux liability for brain penetration.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/deficiência , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Proteínas de Neoplasias/metabolismo , Farmacocinética , Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Células CACO-2 , Permeabilidade da Membrana Celular , Dibenzocicloeptenos/farmacologia , Dicetopiperazinas/farmacologia , Cães , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Células Madin Darby de Rim Canino , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Prazosina/farmacocinética , Quinidina/farmacocinética , Quinolinas/farmacologia , Especificidade por Substrato , Transfecção
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