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1.
Breast Cancer Res ; 26(1): 30, 2024 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378689

RESUMO

INTRODUCTION: Overexpression of prostate-specific membrane antigen (PSMA) on the vasculature of triple-negative breast cancer (TNBC) presents a promising avenue for targeted endogenous radiotherapy with [177Lu]Lu-PSMA-I&T. This study aimed to assess and compare the therapeutic efficacy of a single dose with a fractionated dose of [177Lu]Lu-PSMA-I&T in an orthotopic model of TNBC. METHODS: Rj:NMRI-Foxn1nu/nu mice were used as recipients of MDA-MB-231 xenografts. The single dose group was treated with 1 × 60 ± 5 MBq dose of [177Lu]Lu-PSMA-I&T, while the fractionated dose group received 4 × a 15 ± 2 MBq dose of [177Lu]Lu-PSMA-I&T at 7 day intervals. The control group received 0.9% NaCl. Tumor progression was monitored using [18F]FDG-PET/CT. Ex vivo analysis encompassed immunostaining, TUNEL staining, H&E staining, microautoradiography, and autoradiography. RESULTS: Tumor volumes were significantly smaller in the single dose (p < 0.001) and fractionated dose (p < 0.001) groups. Tumor growth inhibition rates were 38% (single dose) and 30% (fractionated dose). Median survival was notably prolonged in the treated groups compared to the control groups (31d, 28d and 19d for single dose, fractionated dose and control, respectively). [177Lu]Lu-PSMA-I&T decreased the size of viable tumor areas. We further demonstrated, that [177Lu]Lu-PSMA-I&T binds specifically to the tumor-associated vasculature. CONCLUSION: This study highlights the potential of [177Lu]Lu-PSMA-I&T for endogenous radiotherapy of TNBC.


Assuntos
Radioisótopos , Neoplasias de Mama Triplo Negativas , Humanos , Masculino , Animais , Camundongos , Radioisótopos/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Compostos Radiofarmacêuticos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Próstata/metabolismo , Linhagem Celular Tumoral , Dipeptídeos/uso terapêutico
2.
Can J Neurol Sci ; 50(5): 656-661, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-35872570

RESUMO

BACKGROUND AND PURPOSE: A primary admission of patients with suspected acute ischemic stroke and large vessel occlusion (LVO) to centers capable of providing endovascular stroke therapy (EVT) may induce shorter time to treatment and better functional outcomes. One of the limitations in this strategy is the need for accurately identifying LVO patients in the prehospital setting. We aimed to study the feasibility and diagnostic performance of point-of-care ultrasound (POCUS) for the detection of LVO in patients with acute stroke. METHODS: We conducted a proof-of-concept study and selected 15 acute ischemic stroke patients with angiographically confirmed LVO and 15 patients without LVO. Duplex ultrasonography (DUS) of the common carotid arteries was performed, and flow profiles compatible with LVO were scored independently by one experienced and one junior neurologist. RESULTS: Among the 15 patients with LVO, 6 patients presented with an occlusion of the carotid-T and 9 patients presented with an M1 occlusion. Interobserver agreement between the junior and the experienced neurologist was excellent (kappa = 0.813, p < 0.001). Flow profiles of the CAA allowed the detection of LVO with a sensitivity of 73%, a positive predictive value of 92 and 100%, and a c-statistics of 0.83 (95%CI = 0.65-0.94) and 0.87 (95%CI = 0.69-0.94) (experienced neurologist and junior neurologist, respectively). In comparison with clinical stroke scales, DUS was associated with better trade-off between sensitivity and specificity. CONCLUSION: POCUS in acute stroke setting is feasible, it may serve as a complementary tool for the detection of LVO and is potentially applicable in the prehospital phase.


Assuntos
Isquemia Encefálica , Serviços Médicos de Emergência , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Acidente Vascular Cerebral/diagnóstico , Sensibilidade e Especificidade , Ultrassonografia , Isquemia Encefálica/terapia , Estudos Retrospectivos
3.
Eur J Neurol ; 29(8): 2275-2282, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35420727

RESUMO

BACKGROUND AND PURPOSE: It is currently thought that embolic stroke of undetermined source (ESUS) has diverse underlying hidden etiologies, of which cardioembolism is one of the most important. The subgroup of patients with this etiology could theoretically benefit from oral anticoagulation, but it remains unclear if these patients can be correctly identified from other ESUS subgroups and which markers should be used. We aimed to determine whether a machine-learning (ML) model could discriminate between ESUS patients with cardioembolic and those with non-cardioembolic profiles using baseline demographic and laboratory variables. METHODS: Based on a prospective registry of consecutive ischemic stroke patients submitted to acute revascularization therapies, an ML model was trained using the age, sex and 11 selected baseline laboratory parameters of patients with known stroke etiology, with the aim of correctly identifying patients with cardioembolic and non-cardioembolic etiologies. The resulting model was used to classify ESUS patients into those with cardioembolic and those with non-cardioembolic profiles. RESULTS: The ML model was able to distinguish patients with known stroke etiology into cardioembolic or non-cardioembolic profile groups with excellent accuracy (area under the curve = 0.82). When applied to ESUS patients, the model classified 40.3% as having cardioembolic profiles. ESUS patients with cardioembolic profiles were older, more frequently female, more frequently had hypertension, less frequently were active smokers, had higher CHA2 DS2 -VASc (Congestive heart failure or left ventricular systolic dysfunction, Hypertension, Age ≥ 75 [doubled], Diabetes, Stroke/transient ischemic attack [doubled], Vascular disease, Age 65-74, and Sex category) scores, and had more premature atrial complexes per hour. CONCLUSIONS: An ML model based on baseline demographic and laboratory variables was able to classify ESUS patients into cardioembolic or non-cardioembolic profile groups and predicted that 40% of the ESUS patients had a cardioembolic profile.


Assuntos
AVC Embólico , Hipertensão , Embolia Intracraniana , Ataque Isquêmico Transitório , Acidente Vascular Cerebral , Idoso , AVC Embólico/etiologia , Feminino , Humanos , Hipertensão/complicações , Embolia Intracraniana/complicações , Ataque Isquêmico Transitório/complicações , Fatores de Risco , Acidente Vascular Cerebral/complicações
4.
Neurol Sci ; 43(8): 5091-5094, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35590001

RESUMO

INTRODUCTION: Ischemic stroke is a potential complication of hypereosinophilic syndromes (HES), and little is known about underlying pathophysiological mechanisms. We aimed to describe the imaging patterns of cerebral ischemia in patients with HES. METHODS: An individual case is reported. A systematic PubMed review of all records reporting adult patients with HES who suffered ischemic stroke and for whom neuroimaging details of ischemic lesions were available was performed. RESULTS: A 60-year-old man presented with progressive subacute gait difficulty and psychomotor slowing as well as an absolute eosinophilia (2.2 × 109/L) at admission. Brain magnetic resonance tomography revealed multiple acute and subacute internal and external border zone infarcts. Cardiac diagnostic suggested the presence of endomyocarditis. After extensive diagnostic workup, idiopathic HES was diagnosed. The systematic review yielded 183 studies, of which 40 fulfilled the inclusion criteria: a total of 64 patients (31.3% female), with mean age 51.1 years and a median absolute eosinophile count at diagnosis of 10.2 × 109/L were included in the analyses. A border zone pattern of cerebral ischemic lesions was reported in 41 patients (64.1%). Isolated peripheral infarcts were reported in 7 patients (10.9%). Sixteen patients had multiple acute infarcts with no border zone distribution (25.0%). An intracardiac thrombus was reported in 15/60 patients (25%), and findings suggestive of endomyocarditis or endomyocardial fibrosis were found in 31/60 patients (51.7%). CONCLUSIONS: Border zone distribution of cerebral ischemia without hemodynamic compromise is the most frequent imaging pattern in patients with HES, occurring in 2/3 of patients who develop ischemic stroke.


Assuntos
Isquemia Encefálica , Síndrome Hipereosinofílica , AVC Isquêmico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Encefálica/complicações , Isquemia Encefálica/etiologia , Infarto Cerebral/complicações , Síndrome Hipereosinofílica/complicações , Síndrome Hipereosinofílica/diagnóstico por imagem , Imageamento por Ressonância Magnética/efeitos adversos
5.
Arch Gynecol Obstet ; 304(6): 1587-1597, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33903941

RESUMO

Endometrial receptivity is a decisive factor in human reproduction. Human chorionic gonadotropin (hCG) is one of the first embryonic signals that precedes the implantation by trophoblast invasion into the endometrium. Meta-analysis of randomized controlled trials reports a moderate-quality evidence for improved live birth rate for an intrauterine hCG dose ≥ 500 IU. Nevertheless, all hCG endometrial effects are not completely understood. We, therefore, utilized endometrial tissue from 12 patients after estradiol and progesterone treatment with or without intrauterine hCG flushing at the window of implantation (WOI) to analyze cellular composition by measuring marker proteins for stromal, endothelial, epithelial and immune cells. Flow cytometry analysis revealed that significantly more cells expressed the endothelial adhesion molecules VE-cadherin (CD144) and S-Endo-1 (CD146) after intrauterine hCG administration. In contrast, the endothelial marker CD31 and markers involved in vessel formation (VEGFR1 and VEGFR2) remained unchanged in their expression. Similarly, stroma markers (CD73, CD90 and CD105), epithelial markers (Desmocollin-2 and E-Cadherin) and immune cell markers (CD11b, CD45, CD79a and HLA-DR) displayed no alterations in their expression. This finding directs the focus on endothelial adhesion molecules as a potential mechanistically explanation of hCG conveyed increase of embryo implantation and pregnancy rates in women undergoing ART.


Assuntos
Gonadotropina Coriônica , Implantação do Embrião , Moléculas de Adesão Celular , Endométrio , Células Endoteliais , Feminino , Humanos , Gravidez
6.
J Stroke Cerebrovasc Dis ; 30(3): 105518, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33388631

RESUMO

OBJECTIVES: The prognosis of patients with acute ischemic stroke (AIS) essentially depends on both prompt diagnosis and appropriate treatment. Endovascular stroke therapy (EST) proved to be highly efficient in the treatment of emergent large vessel occluding (ELVO) strokes in the anterior circulation. To achieve a timely diagnosis, a robust combination of few and simple signs to identify ELVOs in AIS patients applicable by paramedics in the prehospital triage is worthwhile. MATERIALS AND METHODS: This retrospective single-center study included 904 AIS patients (324 ELVO, 580 non-ELVO) admitted between 2010 and 2015 in a tertiary stroke center. We re-evaluated two symptoms based on NIHSS items, gaze deviation and hemiparesis of the limbs ("Gaze deviation and Paresis Score, GPS") for the pre-hospital prediction of ELVO. RESULTS: A positive GPS AIS in patients predicted ELVO with a sensitivity of 0.89, specificity = 0.97, positive predictive value (PPV) = 0.95, negative predictive value (NPV) = 0.94 and diagnostic odds ratio (DOR) = 34.25 (CI: 20.75-56.53). The positive Likelihood-ratio (LR+) was 29.67, the negative Likelihood ratio (LR-) 0.11. NIHSS of patients with positive GPS (gaze palsy NIHSS ≥ 0, Motor arm NIHSS ≥2 and Motor leg NIHSS ≥2) was markedly higher compared to negative GPS patients (p < 0.001). CONCLUSIONS: The GPS proved to be similarly accurate in detecting ELVO in the anterior circulation of AIS patients and even more specific than other published clinical scores. Its simplicity and clarity might enable non-neurological medical staff to identify ELVO AIS patients with high certainty in a preclinical setting.


Assuntos
Avaliação da Deficiência , Serviços Médicos de Emergência , Fixação Ocular , AVC Isquêmico/diagnóstico , Transtornos da Motilidade Ocular/diagnóstico , Paresia/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Tomada de Decisão Clínica , Procedimentos Endovasculares , Feminino , Humanos , AVC Isquêmico/etiologia , AVC Isquêmico/fisiopatologia , Masculino , Pessoa de Meia-Idade , Transtornos da Motilidade Ocular/etiologia , Transtornos da Motilidade Ocular/fisiopatologia , Paresia/etiologia , Paresia/fisiopatologia , Valor Preditivo dos Testes , Prognóstico , Sistema de Registros , Reprodutibilidade dos Testes , Estudos Retrospectivos , Triagem
7.
Int J Mol Sci ; 23(1)2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-35008586

RESUMO

Ischemic stroke is characterized by an occlusion of a cerebral blood vessel resulting in neuronal cell death due to nutritional and oxygen deficiency. Additionally, post-ischemic cell death is augmented after reperfusion. These events are paralleled by dysregulated miRNA expression profiles in the peri-infarct area. Understanding the underlying molecular mechanism in the peri-infarct region is crucial for developing promising therapeutics. Utilizing a tMCAo (transient Middle Cerebral Artery occlusion) model in rats, we studied the expression levels of the miRNAs (miR) 223-3p, 155-5p, 3473, and 448-5p in the cortex, amygdala, thalamus, and hippocampus of both the ipsi- and contralateral hemispheres. Additionally, the levels in the blood serum, spleen, and liver and the expression of their target genes, namely, Nlrp3, Socs1, Socs3, and Vegfa, were assessed. We observed an increase in all miRNAs on the ipsilateral side of the cerebral cortex in a time-dependent manner and increased miRNAs levels (miR-223-3p, miR-3473, and miR-448-5p) in the contralateral hemisphere after 72 h. Besides the cerebral cortex, the amygdala presented increased expression levels, whereas the thalamus and hippocampus showed no alterations. Different levels of the investigated miRNAs were detected in blood serum, liver, and spleen. The gene targets were altered not only in the peri-infarct area of the cortex but selectively increased in the investigated non-affected brain regions along with the spleen and liver during the reperfusion time up to 72 h. Our results suggest a supra-regional influence of miRNAs following ischemic stroke, which should be studied to further identify whether miRNAs are transported or locally upregulated.


Assuntos
Córtex Cerebral/metabolismo , Hipocampo/metabolismo , Ataque Isquêmico Transitório/metabolismo , Fígado/metabolismo , MicroRNAs/metabolismo , Soro/metabolismo , Baço/metabolismo , Animais , Isquemia Encefálica/metabolismo , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/metabolismo , Masculino , Ratos , Ratos Wistar , Traumatismo por Reperfusão/metabolismo , Acidente Vascular Cerebral/metabolismo
8.
Int J Mol Sci ; 22(21)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34769067

RESUMO

Hypoxia is known to impair mitochondrial and endoplasmic reticulum (ER) homeostasis. Post-hypoxic perturbations of the ER proteostasis result in the accumulation of misfolded/unfolded proteins leading to the activation of the Unfolded Protein Response (UPR). Mitochondrial chaperone TNF receptor-associated protein 1 (TRAP1) is reported to preserve mitochondrial membrane potential and to impede reactive oxygen species (ROS) production thereby protecting cells from ER stress as well as oxidative stress. The first-line antidiabetic drug Metformin has been attributed a neuroprotective role after hypoxia. Interestingly, Metformin has been reported to rescue mitochondrial deficits in fibroblasts derived from a patient carrying a homozygous TRAP1 loss-of-function mutation. We sought to investigate a putative link between Metformin, TRAP1, and the UPR after hypoxia. We assessed post-hypoxic/reperfusion longevity, mortality, negative geotaxis, ROS production, metabolic activity, gene expression of antioxidant proteins, and activation of the UPR in Trap1-deficient flies. Following hypoxia, Trap1 deficiency caused higher mortality and greater impairments in negative geotaxis compared to controls. Similarly, post-hypoxic production of ROS and UPR activation was significantly higher in Trap1-deficient compared to control flies. Metformin counteracted the deleterious effects of hypoxia in Trap1-deficient flies but had no protective effect in wild-type flies. We provide evidence that TRAP1 is crucially involved in the post-hypoxic regulation of mitochondrial/ER stress and the activation of the UPR. Metformin appears to rescue Trap1-deficiency after hypoxia mitigating ROS production and downregulating the pro-apoptotic PERK (protein kinase R-like ER kinase) arm of the UPR.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/genética , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , eIF-2 Quinase/metabolismo , Animais , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Deleção de Genes , Proteínas de Choque Térmico HSP90/metabolismo , Hipóxia/genética , Hipóxia/metabolismo , Masculino , Resposta a Proteínas não Dobradas/efeitos dos fármacos
9.
Int J Mol Sci ; 21(13)2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32645874

RESUMO

Acute ischemic stroke (AIS) is a devastating neurological condition with a lack of neuroprotective therapeutic options, despite the reperfusion modalities thrombolysis and thrombectomy. Post-ischemic brain damage is aggravated by an excessive inflammatory cascade involving the activation and regulation of the pro-inflammatory cytokines IL-1ß and IL-18 by inflammasomes. However, the role of AIM2 and NLRC4 inflammasomes and the influence of the neuroprotective steroids 17ß-estradiol (E2) and progesterone (P) on their regulation after ischemic stroke have not yet been conclusively elucidated. To address the latter, we subjected a total of 65 rats to 1 h of transient Middle Cerebral Artery occlusion (tMCAO) followed by a reperfusion period of 72 h. Moreover, we evaluated the expression and regulation of AIM2 and NLRC4 in glial single-cell cultures (astroglia and microglia) after oxygen-glucose deprivation (OGD). The administration of E2 and P decreased both infarct sizes and neurological impairments after cerebral ischemia in rats. We detected a time-dependent elevation of gene and protein levels (Western Blot/immunohistochemistry) of the AIM2 and NLRC4 inflammasomes in the post-ischemic brains. E2 or P selectively mitigated the stroke-induced increase of AIM2 and NLRC4. While both inflammasomes seemed to be exclusively abundant in neurons under physiological and ischemic conditions in vivo, single-cell cultures of cortical astrocytes and microglia equally expressed both inflammasomes. In line with the in vivo data, E and P selectively reduced AIM2 and NLRC4 in primary cortical astrocytes and microglial cells after OGD. In conclusion, the post-ischemic elevation of AIM2 and NLRC4 and their down-regulation by E2 and P may shed more light on the anti-inflammatory effects of both gonadal hormones after stroke.


Assuntos
Isquemia Encefálica/metabolismo , Proteínas de Ligação a DNA/metabolismo , Estradiol/metabolismo , Hormônios Gonadais/metabolismo , Inflamassomos/metabolismo , Receptores de Superfície Celular/metabolismo , Regulação para Cima/fisiologia , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Astrócitos/metabolismo , Encéfalo/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Masculino , Microglia/metabolismo , Neurônios/metabolismo , Ratos , Ratos Wistar , Reperfusão/métodos , Acidente Vascular Cerebral/metabolismo
10.
Int J Mol Sci ; 20(21)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683519

RESUMO

Ischemic stroke is known to cause the accumulation of misfolded proteins and loss of calcium homeostasis leading to impairment of endoplasmic reticulum (ER) function. The unfolded protein response (UPR) is an ER-located and cytoprotective pathway that aims to resolve ER stress. Transmembrane BAX inhibitor-1 motif-containing (TMBIM) protein family member TMBIM3/GRINA is highly expressed in the brain and mostly located at the ER membrane suppressing ER calcium release by inositol-1,4,5-trisphosphate receptors. GRINA confers neuroprotection and is regulated by erythropoietin (EPO) after murine cerebral ischemia. However, the role of GRINA and the impact of EPO treatment on the post-ischemic UPR have not been elucidated yet. We subjected GRINA-deficient (Grina-/-) and wildtype mice to transient (30 min) middle cerebral artery occlusion (tMCAo) followed by 6 h or 72 h of reperfusion. We administered EPO or saline 0, 24 and 48 h after tMCAo/sham surgery. Oxygen-glucose deprivation (OGD) and pharmacological stimulation of the UPR using Tunicamycin and Thapsigargin were carried out in primary murine cortical mixed cell cultures. Treatment with the PERK-inhibitor GSK-2606414, IRE1a-RNase-inhibitor STF-083010 and EPO was performed 1 h prior to either 1 h, 2 h or 3 h of OGD. We found earlier and larger infarct demarcations in Grina-/- mice compared to wildtype mice, which was accompanied by a worse neurological outcome and an abolishment of EPO-mediated neuroprotection after ischemic stroke. In addition, GRINA-deficiency increased apoptosis and the activation of the corresponding PERK arm of the UPR after stroke. EPO enhanced the post-ischemic activation of pro-survival IRE1a and counteracted the pro-apoptotic PERK branch of the UPR. Both EPO and the PERK-inhibitor GSK-2606414 reduced cell death and regulated Grina mRNA levels after OGD. In conclusion, GRINA plays a crucial role in post-ischemic UPR and the use of both GSK-2606414 and EPO might lead to neuroprotection.


Assuntos
Eritropoetina/farmacologia , Ataque Isquêmico Transitório/prevenção & controle , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Células Cultivadas , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/genética , Glucose/metabolismo , Indóis/farmacologia , Infarto da Artéria Cerebral Média/genética , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/prevenção & controle , Ataque Isquêmico Transitório/genética , Ataque Isquêmico Transitório/metabolismo , Masculino , Proteínas de Membrana/genética , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Fármacos Neuroprotetores/farmacologia , Oxigênio/metabolismo , Sulfonamidas/farmacologia , Tapsigargina/farmacologia , Tiofenos/farmacologia , Tunicamicina/farmacologia , Resposta a Proteínas não Dobradas/genética
11.
J Neurochem ; 147(5): 678-691, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30152864

RESUMO

Parkinson's disease (PD) is characterized by the loss of midbrain dopaminergic neurons and aggregates of α-synuclein termed Lewy bodies. Fingolimod (FTY720) is an agonist of sphingosine-1 phosphate receptors and an approved oral treatment for multiple sclerosis. Fingolimod elevates brain-derived neurotrophic factor (BDNF), an important neurotrophic factor for dopaminergic neurons. BDNF and fingolimod are beneficial in several animal models of PD. In order to validate the therapeutic potential of fingolimod for the treatment of PD, we tested its effect in the subacute MPTP mouse model of PD. MPTP or vehicle was applied i.p. in doses of 30 mg/kg MPTP on five consecutive days. In order to recapitulate the combination of dopamine loss and α-synuclein aggregates found in PD, MPTP was first administered in Thy1-A30P-α-synuclein transgenic mice. Fingolimod was administered i.p. at a dose of 0.1 mg/kg every second day. Nigrostriatal degeneration was assayed by stereologically counting the number of dopaminergic neurons in the substantia nigra pars compacta, by analysing the concentration of catecholamines and the density of dopaminergic fibres in the striatum. MPTP administration produced a robust nigrostriatal degeneration, comparable to previous studies. Unexpectedly, we found no difference between mice with and without fingolimod treatment, neither at baseline, nor at 14 or 90 days after MPTP. Also, we found no effect of fingolimod in the subacute MPTP mouse model when we used wildtype mice instead of α-synuclein transgenic mice, and no effect with an increased dose of 1 mg/kg fingolimod administered every day. In order to explain these findings, we analysed BDNF regulation by fingolimod. We did find an increase of BDNF protein after a single injection of fingolimod 0.1 or 1.0 mg/kg, but not after multiple injections, indicating that the BDNF response to fingolimod is unsustainable over time. Taken together we did not observe a neuroprotective effect of fingolimod in the subacute MPTP mouse model of PD. We discuss possible explanations for this discrepancy with previous findings and conclude fingolimod might be beneficial for the nonmotor symptoms of PD. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* and *Open Data* because it provided all relevant information to reproduce the study in the manuscript and because it made the data publicly available. The data can be accessed at https://osf.io/6xgfn/. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.


Assuntos
Antiparkinsonianos/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Cloridrato de Fingolimode/uso terapêutico , Intoxicação por MPTP/prevenção & controle , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson Secundária/prevenção & controle , Animais , Dopamina/metabolismo , Neurônios Dopaminérgicos/patologia , Humanos , Imuno-Histoquímica , Intoxicação por MPTP/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Resultados Negativos , Doença de Parkinson Secundária/patologia , Substância Negra/patologia , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
12.
J Neurochem ; 145(3): 258-270, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29315561

RESUMO

Delayed cell death in the penumbra region of acute ischemic stroke occurs through apoptotic mechanisms, making it amenable to therapeutic interventions. Fas/CD95 mediates apoptotic cell death in response to external stimuli. In mature neurons, Fas/CD95 signaling is modulated by Fas-apoptotic inhibitory molecule 2 (Faim2), which reduces cell death in animal models of stroke, meningitis, and Parkinson disease. Erythropoietin (EPO) has been studied as a therapeutic strategy in ischemic stroke. Erythropoietin stimulates the phosphatidylinositol-3 kinase/Akt (PI3K/Akt) pathway, which regulates Faim2 expression. Therefore, up-regulation of Faim2 may contribute to neuroprotection by EPO. Male Faim2-deficient mice (Faim2-/- ) and wild-type littermates (WT) were subjected to 30 min of middle cerebral artery occlusion (MCAo) followed by 72 h of reperfusion. EPO was applied before (30 min) and after (24 and 48 h) MCAo. In WT mice application of EPO at a low dose (5000 U/kg) significantly reduced stroke volume, whereas treatment with high dose (90 000 U/kg) did not. In Faim2-/- animals administration of low-dose EPO did not result in a significant reduction in stroke volume. Faim2 expression as measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR) increased after low-dose EPO but not with high dose. An extensive phenotyping including analysis of cerebral vessel architecture did not reveal confounding differences between the genotypes. In human post-mortem brain Faim2 displayed a differential expression in areas of penumbral ischemia. Faim2 up-regulation may contribute to the neuroprotective effects of low-dose erythropoietin in transient brain ischemia. The dose-dependency may explain mixed effects of erythropoietin observed in clinical stroke trials.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Eritropoetina , Ataque Isquêmico Transitório/metabolismo , Proteínas de Membrana/metabolismo , Neuroproteção/fisiologia , Idoso , Animais , Eritropoetina/metabolismo , Eritropoetina/farmacologia , Feminino , Humanos , Ataque Isquêmico Transitório/patologia , Ataque Isquêmico Transitório/fisiopatologia , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo
13.
J Neuroinflammation ; 15(1): 282, 2018 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-30261895

RESUMO

BACKGROUND: Neuroinflammation has an essential impact on the pathogenesis and progression of Alzheimer's disease (AD). Mostly mediated by microglia and astrocytes, inflammatory processes lead to degeneration of neuronal cells. The NLRP3-inflammasome (NOD-like receptor family, pyrin domain containing 3) is a key component of the innate immune system and its activation results in secretion of the proinflammatory effectors interleukin-1ß (IL-1ß) and interleukin-18 (IL-18). Under physiological conditions, cytosolic NLRP3-inflammsome is maintained in an inactive form, not able to oligomerize. Amyloid ß1-42 (Aß1-42) triggers activation of NLRP3-inflammasome in microglia and astrocytes, inducing oligomerization and thus recruitment of proinflammatory proteases. NLRP3-inflammasome was found highly expressed in human brains diagnosed with AD. Moreover, NLRP3-deficient mice carrying mutations associated with familial AD were partially protected from deficits associated with AD. The endogenous protease inhibitor α1-antitrypsin (A1AT) is known for its anti-inflammatory and anti-apoptotic properties and thus could serve as therapeutic agent for NLRP3-inhibition. A1AT protects neurons from glutamate-induced toxicity and reduces Aß1-42-induced inflammation in microglial cells. In this study, we investigated the effect of Aß1-42-induced NLRP3-inflammasome upregulation in primary murine astrocytes and its regulation by A1AT. METHODS: Primary cortical astrocytes from BALB/c mice were stimulated with Aß1-42 and treated with A1AT. Regulation of NLRP3-inflammasome was examined by immunocytochemistry, PCR, western blot and ELISA. Our studies included an inhibitor of NLRP3 to elucidate direct interactions between A1AT and NLRP3-inflammasome components. RESULTS: Our study revealed that A1AT reduces Aß1-42-dependent upregulation of NLRP3 at the mRNA and protein levels. Furthermore, A1AT time-dependently mitigated the expression of caspase 1 and its cleavage product IL-1ß in Aß1-42-stimulated astrocytes. CONCLUSION: We conclude that Aß1-42-stimulation results in an upregulation of NLRP3, caspase 1, and its cleavage products in astrocytes. A1AT time-dependently hampers neuroinflammation by downregulation of Aß1-42-mediated NLRP3-inflammasome expression and thus may serve as a pharmaceutical opportunity for the treatment of Alzheimer's disease.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Astrócitos/efeitos dos fármacos , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fragmentos de Peptídeos/toxicidade , Inibidores da Tripsina/farmacologia , alfa 1-Antitripsina/farmacologia , Animais , Animais Recém-Nascidos , Encéfalo/citologia , Células Cultivadas , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Furanos , Proteína Glial Fibrilar Ácida/metabolismo , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Indenos , Inflamassomos/metabolismo , L-Lactato Desidrogenase/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Sulfonamidas , Sulfonas/farmacologia , Regulação para Cima/efeitos dos fármacos
14.
J Stroke Cerebrovasc Dis ; 27(10): 2669-2676, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29970323

RESUMO

BACKGROUND: Access to reperfusion therapies in patients with large vessel occluding acute ischemic stroke demands process reorganization and optimization. Neurovascular networks are being built up to provide 24/7 endovascular stroke therapy service. In times of an increasingly complex stroke rescue chain little is known about patients' and their relatives' treatment awareness. METHODS: All patients, who received any kind of acute reperfusion treatment between January and August 2017 in the university hospital Aachen, and their proxies, were included in the survey. Patients were either primarily or secondarily transferred. RESULTS: For all questions regarding stroke treatment patients and their caregivers provided concurring answers. 40% of both patients and caregivers did not understand the treatment that was performed. Finally, patients who perceived on their own that stroke detection was delayed had significantly longer onset to door times than patients who did not have this impression. CONCLUSIONS: This study showed that patients' and proxies' answers correlated significantly. In case of patients' unavailability extrapolation of treatment satisfaction from answers by proxies might be permitted. High percentages of patients and caregivers do not understand relevant information, possibly due to limits of communication in an emergency setting or deficits in communication during the hospital stay. More emphasis should be laid on providing further information during the hospital stay.


Assuntos
Compreensão , Procedimentos Endovasculares , Conhecimentos, Atitudes e Prática em Saúde , Pacientes/psicologia , Acidente Vascular Cerebral/terapia , Terapia Trombolítica , Cuidadores/psicologia , Terapia Combinada , Procedimentos Endovasculares/efeitos adversos , Alemanha , Hospitais Universitários , Humanos , Comunicação Interdisciplinar , Equipe de Assistência ao Paciente , Participação do Paciente , Satisfação do Paciente , Prognóstico , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/psicologia , Terapia Trombolítica/efeitos adversos , Tempo para o Tratamento
15.
Neuroendocrinology ; 99(3-4): 156-67, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24685982

RESUMO

17ß-Estradiol (E2) and progesterone (P) are neuroprotective in acute brain injury by attenuating neuropathophysiological processes and regulating local glial function. Besides controlling brain-intrinsic immune responses, astrocytes are cellular targets for sex steroids in health and disease and typically resist to hypoxic damage. In this in vitro study, we aimed at uncovering astroglia-specific reactions to sublethal hypoxic conditions and astroglia-specific effects of both sex steroid hormones on these parameters. Short-term hypoxia for 3 h increased reactive oxygen species production, but had no influence on cell viability of cerebral cortical rat astroglia. Astrocytes expressed classical estrogen receptors (ER), progesterone receptor (PR), and a set of nonclassical steroid hormone receptors. Hypoxia specifically induced ERα and PR isoform A gene expression. Oxygen deprivation increased gene expression of aquaporin-4 (AQP4), hypoxia-inducible factor 1α (Hif1α), and cyclooxygenase-2 (COX2). The application of E2 and P selectively prevented this induction. Effects on protein levels of these genes appeared to be delayed. These data show that astrocytes change their receptivity for sex steroid hormones by switching steroid hormone receptor expression and that E2 and P modify or antagonize proinflammatory COX2 synthesis, edema-promoting AQP4 expression, and the Hif1α increase. In vivo studies have to address whether these cell responses contribute to steroid-mediated neuroprotection in stroke.


Assuntos
Aquaporina 4/metabolismo , Astrócitos/efeitos dos fármacos , Córtex Cerebral/citologia , Ciclo-Oxigenase 2/metabolismo , Estradiol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/metabolismo , Progesterona/farmacologia , Análise de Variância , Animais , Animais Recém-Nascidos , Aquaporina 4/genética , Astrócitos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ciclo-Oxigenase 2/genética , Ensaio de Imunoadsorção Enzimática , Proteína Glial Fibrilar Ácida/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , RNA Mensageiro/metabolismo , Ratos
16.
Adv Mater ; 36(32): e2403752, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38804595

RESUMO

Polymer mechanochemistry utilizes mechanical force to activate latent functionalities in macromolecules and widely relies on ultrasonication techniques. Fundamental constraints of frequency and power intensity have prohibited the application of the polymer mechanochemistry principles in a biomedical context up to now, although medical ultrasound is a clinically established modality. Here, a universal polynucleotide framework is presented that allows the binding and release of therapeutic oligonucleotides, both DNA- and RNA-based, as cargo by biocompatible medical imaging ultrasound. It is shown that the high molar mass, colloidal assembly, and a distinct mechanochemical mechanism enable the force-induced release of cargo and subsequent activation of biological function in vitro and in vivo. Thereby, this work introduces a platform for the exploration of biological questions and therapeutics development steered by mechanical force.


Assuntos
Polímeros , Polinucleotídeos , Polinucleotídeos/química , Polímeros/química , Animais , DNA/química , Humanos , Camundongos , RNA/química , RNA/metabolismo , Fenômenos Mecânicos
17.
Clin Neurol Neurosurg ; 245: 108501, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39173492

RESUMO

PURPOSE: Interventional stroke therapy has become standard treatment for patients with acute ischemic strokes. Complete reperfusion (eTICI 3) portrays the best possible technical outcome. The purpose of this study was to determine possible predictors for an unfavorable neurological long-term outcome (mRS 3-6) despite achieving the best possible treatment success. METHODS: We evaluated 122 patients with stroke in the anterior circulation and complete reperfusion after mechanical thrombectomy (MT) between May 2010 and March 2020. We performed a binary logistic regression analysis with patient baseline data, stroke severity, comorbidities, premedication and treatment information as independent variables. RESULTS: 50 of the 122 patients included in our study showed a poor clinical outcome after 90 days (41 %). Multivariable logistic regression analysis showed that older age (p = 0.033), higher admission NIHSS (p=0.009), lower admission ASPECTS (p=0.005), a pre-existing cardiovascular disease (p=0.017), and multiple passes for complete reperfusion (p=0.030) had an independent impact on unfavorable outcome. CONCLUSIONS: Older age, higher NIHSS upon admission, lower ASPECTS upon admission, cardiovascular comorbidities and multiple passes for complete reperfusion are predictors for poor neurological long-term outcome despite complete reperfusion.


Assuntos
AVC Isquêmico , Reperfusão , Trombectomia , Humanos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Resultado do Tratamento , AVC Isquêmico/cirurgia , AVC Isquêmico/terapia , Idoso de 80 Anos ou mais , Reperfusão/métodos , Fatores Etários , Prognóstico
18.
ACS Appl Mater Interfaces ; 15(42): 48963-48977, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37831583

RESUMO

Identification and selectivity of molecular targets with prolonged action for difficult-to-target cancer such as triple-negative breast cancer (TNBC) represent a persisting challenge in the precision delivery of therapeutics. In the quest to target undruggable sites, this study validates the bioavailability of polydopamine-sealed mesoporous silica nanocarriers (PDA-mSiO2) for in vivo drug delivery to TNBC. For controlled transport and release, the chemotherapeutic drug doxorubicin was encapsulated in mSiO2 nanocarriers coated with a PDA layer serving as a stimuli-responsive gatekeeper or seal. For unifying targeting and treatment modalities, these nanocarriers were covalently conjugated to a macrocyclic chelator (DOTA) and folate (FA-mSiO2.) that enabled incorporation of radionuclides and identification of FR Alpha (FolRα) receptors present on TNBC cells. The robust chemical design of FA- and DOTA-functionalized PDA-coated mSiO2 nanocarriers constitutes mild reaction conditions to avoid the loss of surface-bound molecules. The radiolabeling studies with the theranostic pair 68Ga and 177Lu showed quantitative trends for radiochemical efficacy and purity. Nanocarriers equipped with both radiolabels and affinity ligands were optimally stable when incubated with human serum for up to 120 h (177Lu), demonstrating hydrophilicity with a partition coefficient (log P) of -3.29 ± 0.08. Specifically, when incubated with TNBC cells, the cells received significant FA-mSiO2 carriers, demonstrating efficient carrier internalization and time-dependent uptake. Moreover, in vivo results visualize the retention of drug-filled carriers at the tumor sites for a long time, which holds promise for therapeutic studies. This research work demonstrates for the first time the successful dual conjugation of nanocarriers through the colocation of radionuclides and anticancer drugs that is promising for both live molecular imaging and enhanced therapeutic effect for TNBC.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Antineoplásicos/química , Doxorrubicina/farmacologia , Doxorrubicina/química , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/química , Radioisótopos , Dióxido de Silício/química , Nanopartículas/química
19.
STAR Protoc ; 3(3): 101634, 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-36035795

RESUMO

Hypoxia plays a pivotal role in the pathogenesis of major causes of mortality such as cerebral ischemia. Here, we present a standardized protocol for the induction of global hypoxia and reoxygenation in Drosophila melanogaster, with details on subsequent analysis of mortality, neurobehavioral impairments, and molecular mechanisms. This protocol emphasizes the importance of controlling and monitoring specific environmental parameters to ensure reproducible results. It also highlights profound differences that can arise from variations in the age and genotype of the flies. For complete details on the use and execution of this protocol, please refer to Habib et al. (2021).


Assuntos
Drosophila melanogaster , Oxigênio , Animais , Hipóxia
20.
Front Cell Neurosci ; 16: 915348, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35813499

RESUMO

Recombinant human erythropoietin (rhEPO) has been shown to exert anti-apoptotic and anti-inflammatory effects after cerebral ischemia. Inflammatory cytokines interleukin-1ß and -18 (IL-1ß and IL-18) are crucial mediators of apoptosis and are maturated by multiprotein complexes termed inflammasomes. Microglia are the first responders to post-ischemic brain damage and are a main source of inflammasomes. However, the impact of rhEPO on microglial activation and the subsequent induction of inflammasomes after ischemia remains elusive. To address this, we subjected human microglial clone 3 (HMC-3) cells to various durations of oxygen-glucose-deprivation/reperfusion (OGD/R) to assess the impact of rhEPO on cell viability, metabolic activity, oxidative stress, phagocytosis, migration, as well as on the regulation and activation of the NLRP1, NLRP3, NLRC4, and AIM2 inflammasomes. Administration of rhEPO mitigated OGD/R-induced oxidative stress and cell death. Additionally, it enhanced metabolic activity, migration and phagocytosis of HMC-3. Moreover, rhEPO attenuated post-ischemic activation and regulation of the NLRP1, NLRP3, NLRC4, and AIM2 inflammasomes as well as their downstream effectors CASPASE1 and IL-1ß. Pharmacological inhibition of NLRP3 via MCC950 had no effect on the activation of CASPASE1 and maturation of IL-1ß after OGD/R, but increased protein levels of NLRP1, NLRC4, and AIM2, suggesting compensatory activities among inflammasomes. We provide evidence that EPO-conveyed anti-inflammatory actions might be mediated via the regulation of the inflammasomes.

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