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1.
N Engl J Med ; 387(22): 2045-2055, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36449420

RESUMO

BACKGROUND: Iron content is increased in the substantia nigra of persons with Parkinson's disease and may contribute to the pathophysiology of the disorder. Early research suggests that the iron chelator deferiprone can reduce nigrostriatal iron content in persons with Parkinson's disease, but its effects on disease progression are unclear. METHODS: We conducted a multicenter, phase 2, randomized, double-blind trial involving participants with newly diagnosed Parkinson's disease who had never received levodopa. Participants were assigned (in a 1:1 ratio) to receive oral deferiprone at a dose of 15 mg per kilogram of body weight twice daily or matched placebo for 36 weeks. Dopaminergic therapy was withheld unless deemed necessary for symptom control. The primary outcome was the change in the total score on the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS; range, 0 to 260, with higher scores indicating more severe impairment) at 36 weeks. Secondary and exploratory clinical outcomes at up to 40 weeks included measures of motor and nonmotor disability. Brain iron content measured with the use of magnetic resonance imaging was also an exploratory outcome. RESULTS: A total of 372 participants were enrolled; 186 were assigned to receive deferiprone and 186 to receive placebo. Progression of symptoms led to the initiation of dopaminergic therapy in 22.0% of the participants in the deferiprone group and 2.7% of those in the placebo group. The mean MDS-UPDRS total score at baseline was 34.3 in the deferiprone group and 33.2 in the placebo group and increased (worsened) by 15.6 points and 6.3 points, respectively (difference, 9.3 points; 95% confidence interval, 6.3 to 12.2; P<0.001). Nigrostriatal iron content decreased more in the deferiprone group than in the placebo group. The main serious adverse events with deferiprone were agranulocytosis in 2 participants and neutropenia in 3 participants. CONCLUSIONS: In participants with early Parkinson's disease who had never received levodopa and in whom treatment with dopaminergic medications was not planned, deferiprone was associated with worse scores in measures of parkinsonism than those with placebo over a period of 36 weeks. (Funded by the European Union Horizon 2020 program; FAIRPARK-II ClinicalTrials.gov number, NCT02655315.).


Assuntos
Antiparkinsonianos , Deferiprona , Quelantes de Ferro , Ferro , Doença de Parkinson , Substância Negra , Humanos , Deferiprona/administração & dosagem , Deferiprona/efeitos adversos , Deferiprona/farmacologia , Deferiprona/uso terapêutico , Ferro/análise , Ferro/metabolismo , Levodopa/uso terapêutico , Neutropenia/induzido quimicamente , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Doença de Parkinson/fisiopatologia , Quelantes de Ferro/administração & dosagem , Quelantes de Ferro/efeitos adversos , Quelantes de Ferro/farmacologia , Quelantes de Ferro/uso terapêutico , Substância Negra/química , Substância Negra/diagnóstico por imagem , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo , Progressão da Doença , Método Duplo-Cego , Administração Oral , Encéfalo/diagnóstico por imagem , Química Encefálica , Dopaminérgicos/administração & dosagem , Dopaminérgicos/efeitos adversos , Dopaminérgicos/farmacologia , Dopaminérgicos/uso terapêutico , Antiparkinsonianos/administração & dosagem , Antiparkinsonianos/efeitos adversos , Antiparkinsonianos/farmacologia , Antiparkinsonianos/uso terapêutico
2.
Toxics ; 11(10)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37888697

RESUMO

Electronic cigarettes (e-cig) and heated tobacco products (HTP) are often used as smoking cessation aids, while the harm reduction effects of these alternatives to cigarettes are still the subject of controversial debate, in particular regarding their carcinogenic potential. The objective of this study is to compare the effects of e-cig, HTP and conventional cigarette emissions on the generation of oxidative stress and genetic and epigenetic lesions in human bronchial epithelial BEAS-2B cells. Our results show that HTP were less cytotoxic than conventional cigarettes while e-cig were not substantially cytotoxic in BEAS-2B cells. E-cig had no significant effect on the Nrf2 pathway, whereas HTP and cigarettes increased the binding activity of Nrf2 to antioxidant response elements and the expression of its downstream targets HMOX1 and NQO1. Concordantly, only HTP and cigarettes induced oxidative DNA damage and significantly increased DNA strand breaks and chromosomal aberrations. Neither histone modulations nor global DNA methylation changes were found after acute exposure, regardless of the type of emissions. In conclusion, this study reveals that HTP, unlike e-cig, elicit a biological response very similar to that of cigarettes, but only after a more intensive exposure: both tobacco products induce cytotoxicity, Nrf2-dependent oxidative stress and genetic lesions in human epithelial pulmonary cells. Therefore, the health risk of HTP should not be underestimated and animal studies are required in order to determine the tumorigenic potential of these emerging products.

3.
Environ Int ; 181: 108248, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37857188

RESUMO

More than 7 million early deaths/year are attributable to air pollution. Current health concerns are especially focused on air pollution-derived particulate matter (PM). Although oxidative stress-induced airway inflammation is one of the main adverse outcome pathways triggered by air pollution-derived PM, the persistence of both these underlying mechanisms, even after exposure cessation, remained poorly studied. In this study, A/JOlaHsd mice were also exposed acutely (24 h) or sub-chronically (4 weeks), with or without a recovery period (12 weeks), to two urban PM2.5 samples collected during contrasting seasons (i.e., autumn/winter, AW or spring/summer, SS). The distinct intrinsic oxidative potentials (OPs) of AW and SS PM2.5, as evaluated in acellular conditions, were closely related to their respective physicochemical characteristics and their respective ability to really generate ROS over-production in the mouse lungs. Despite the early activation of the nuclear factor erythroid 2-related factor 2 (Nrf2) cell signaling pathway by AW and, in a lesser degree, SS PM2.5, in the murine lungs after acute and sub-chronic exposures, the critical redox homeostasis was not restored, even after the exposure cessation. Accordingly, an inflammatory response was reported through the activation of the nuclear factor-kappa B (NF-κB) cell signaling pathway activation, the secretion of cytokines, and the recruitment of inflammatory cells, in the murine lungs after the acute and sub-chronic exposures to AW and, in a lesser extent, to SS PM2.5, which persisted after the recovery period. Taken together, these original results provided, for the first time, new relevant insights that air pollution-derived PM2.5, with relatively high intrinsic OPs, induced oxidative stress and inflammation, which persisted admittedly at a lower level in the lungs after the exposure cessation, thereby contributing to the occurrence of molecular and cellular adverse events leading to the development and/or exacerbation of future chronic inflammatory lung diseases and even cancers.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Camundongos , Animais , Material Particulado/análise , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Pulmão , Inflamação/induzido quimicamente , Estresse Oxidativo
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