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1.
EMBO Rep ; 25(1): 254-285, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38177910

RESUMO

Midbrain dopaminergic neurons (mDANs) control voluntary movement, cognition, and reward behavior under physiological conditions and are implicated in human diseases such as Parkinson's disease (PD). Many transcription factors (TFs) controlling human mDAN differentiation during development have been described, but much of the regulatory landscape remains undefined. Using a tyrosine hydroxylase (TH) human iPSC reporter line, we here generate time series transcriptomic and epigenomic profiles of purified mDANs during differentiation. Integrative analysis predicts novel regulators of mDAN differentiation and super-enhancers are used to identify key TFs. We find LBX1, NHLH1 and NR2F1/2 to promote mDAN differentiation and show that overexpression of either LBX1 or NHLH1 can also improve mDAN specification. A more detailed investigation of TF targets reveals that NHLH1 promotes the induction of neuronal miR-124, LBX1 regulates cholesterol biosynthesis, and NR2F1/2 controls neuronal activity.


Assuntos
Neurônios Dopaminérgicos , Células-Tronco Pluripotentes Induzidas , Humanos , Neurônios Dopaminérgicos/metabolismo , Multiômica , Mesencéfalo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Diferenciação Celular/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética
2.
Mol Cell ; 69(4): 594-609.e8, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29452639

RESUMO

Accumulating evidence indicates that the MDM2 oncoprotein promotes tumorigenesis beyond its canonical negative effects on the p53 tumor suppressor, but these p53-independent functions remain poorly understood. Here, we show that a fraction of endogenous MDM2 is actively imported in mitochondria to control respiration and mitochondrial dynamics independently of p53. Mitochondrial MDM2 represses the transcription of NADH-dehydrogenase 6 (MT-ND6) in vitro and in vivo, impinging on respiratory complex I activity and enhancing mitochondrial ROS production. Recruitment of MDM2 to mitochondria increases during oxidative stress and hypoxia. Accordingly, mice lacking MDM2 in skeletal muscles exhibit higher MT-ND6 levels, enhanced complex I activity, and increased muscular endurance in mild hypoxic conditions. Furthermore, increased mitochondrial MDM2 levels enhance the migratory and invasive properties of cancer cells. Collectively, these data uncover a previously unsuspected function of the MDM2 oncoprotein in mitochondria that play critical roles in skeletal muscle physiology and may contribute to tumor progression.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Transformação Celular Neoplásica/patologia , Complexo I de Transporte de Elétrons/metabolismo , Regulação Neoplásica da Expressão Gênica , Mitocôndrias/patologia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Movimento Celular , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Complexo I de Transporte de Elétrons/genética , Genoma Mitocondrial , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/genética , Mitocôndrias/metabolismo , Invasividade Neoplásica , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-mdm2/genética , Transdução de Sinais , Transcrição Gênica , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Ann Neurol ; 96(1): 133-149, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38767023

RESUMO

OBJECTIVE: The aim of our study is to better understand the genetic architecture and pathological mechanisms underlying neurodegeneration in idiopathic Parkinson's disease (iPD). We hypothesized that a fraction of iPD patients may harbor a combination of common variants in nuclear-encoded mitochondrial genes ultimately resulting in neurodegeneration. METHODS: We used mitochondria-specific polygenic risk scores (mitoPRSs) and created pathway-specific mitoPRSs using genotype data from different iPD case-control datasets worldwide, including the Luxembourg Parkinson's Study (412 iPD patients and 576 healthy controls) and COURAGE-PD cohorts (7,270 iPD cases and 6,819 healthy controls). Cellular models from individuals stratified according to the most significant mitoPRS were subsequently used to characterize different aspects of mitochondrial function. RESULTS: Common variants in genes regulating Oxidative Phosphorylation (OXPHOS-PRS) were significantly associated with a higher PD risk in independent cohorts (Luxembourg Parkinson's Study odds ratio, OR = 1.31[1.14-1.50], p-value = 5.4e-04; COURAGE-PD OR = 1.23[1.18-1.27], p-value = 1.5e-29). Functional analyses in fibroblasts and induced pluripotent stem cells-derived neuronal progenitors revealed significant differences in mitochondrial respiration between iPD patients with high or low OXPHOS-PRS (p-values < 0.05). Clinically, iPD patients with high OXPHOS-PRS have a significantly earlier age at disease onset compared to low-risk patients (false discovery rate [FDR]-adj p-value = 0.015), similar to prototypic monogenic forms of PD. Finally, iPD patients with high OXPHOS-PRS responded more effectively to treatment with mitochondrially active ursodeoxycholic acid. INTERPRETATION: OXPHOS-PRS may provide a precision medicine tool to stratify iPD patients into a pathogenic subgroup genetically defined by specific mitochondrial impairment, making these individuals eligible for future intelligent clinical trial designs. ANN NEUROL 2024;96:133-149.


Assuntos
Mitocôndrias , Herança Multifatorial , Doença de Parkinson , Humanos , Doença de Parkinson/genética , Doença de Parkinson/patologia , Herança Multifatorial/genética , Mitocôndrias/genética , Masculino , Feminino , Fosforilação Oxidativa , Pessoa de Meia-Idade , Idoso , Estudos de Casos e Controles , Células-Tronco Pluripotentes Induzidas , Predisposição Genética para Doença/genética , Estratificação de Risco Genético
4.
Europace ; 26(7)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38938169

RESUMO

AIMS: Subclinical atrial fibrillation (AF) is associated with increased risk of progression to clinical AF, stroke, and cardiovascular death. We hypothesized that in pacemaker patients requiring dual-chamber rate-adaptive (DDDR) pacing, closed loop stimulation (CLS) integrated into the circulatory control system through intra-cardiac impedance monitoring would reduce the occurrence of atrial high-rate episodes (AHREs) compared with conventional DDDR pacing. METHODS AND RESULTS: Patients with sinus node dysfunctions (SNDs) and an implanted pacemaker or defibrillator were randomly allocated to dual-chamber CLS (n = 612) or accelerometer-based DDDR pacing (n = 598) and followed for 3 years. The primary endpoint was time to the composite endpoint of the first AHRE lasting ≥6 min, stroke, or transient ischaemic attack (TIA). All AHREs were independently adjudicated using intra-cardiac electrograms. The incidence of the primary endpoint was lower in the CLS arm (50.6%) than in the DDDR arm (55.7%), primarily due to the reduction in AHREs lasting between 6 h and 7 days. Unadjusted site-stratified hazard ratio (HR) for CLS vs. DDDR was 0.84 [95% confidence interval (CI), 0.72-0.99; P = 0.035]. After adjusting for CHA2DS2-VASc score, the HR remained 0.84 (95% CI, 0.71-0.99; P = 0.033). In subgroup analyses of AHRE incidence, the incremental benefit of CLS was greatest in patients without atrioventricular block (HR, 0.77; P = 0.008) and in patients without AF history (HR, 0.73; P = 0.009). The contribution of stroke/TIA to the primary endpoint (1.3%) was low and not statistically different between study arms. CONCLUSION: Dual-chamber CLS in patients with SND is associated with a significantly lower AHRE incidence than conventional DDDR pacing.


Assuntos
Fibrilação Atrial , Estimulação Cardíaca Artificial , Frequência Cardíaca , Ataque Isquêmico Transitório , Marca-Passo Artificial , Síndrome do Nó Sinusal , Acidente Vascular Cerebral , Humanos , Feminino , Masculino , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/terapia , Fibrilação Atrial/epidemiologia , Idoso , Síndrome do Nó Sinusal/terapia , Síndrome do Nó Sinusal/fisiopatologia , Estimulação Cardíaca Artificial/métodos , Ataque Isquêmico Transitório/prevenção & controle , Ataque Isquêmico Transitório/epidemiologia , Pessoa de Meia-Idade , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/epidemiologia , Incidência , Resultado do Tratamento , Fatores de Tempo , Fatores de Risco , Desfibriladores Implantáveis , Técnicas Eletrofisiológicas Cardíacas , Acelerometria , Idoso de 80 Anos ou mais
5.
Mol Cell ; 62(6): 890-902, 2016 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-27264869

RESUMO

The mouse double minute 2 (MDM2) oncoprotein is recognized as a major negative regulator of the p53 tumor suppressor, but growing evidence indicates that its oncogenic activities extend beyond p53. Here, we show that MDM2 is recruited to chromatin independently of p53 to regulate a transcriptional program implicated in amino acid metabolism and redox homeostasis. Identification of MDM2 target genes at the whole-genome level highlights an important role for ATF3/4 transcription factors in tethering MDM2 to chromatin. MDM2 recruitment to chromatin is a tightly regulated process that occurs during oxidative stress and serine/glycine deprivation and is modulated by the pyruvate kinase M2 (PKM2) metabolic enzyme. Depletion of endogenous MDM2 in p53-deficient cells impairs serine/glycine metabolism, the NAD(+)/NADH ratio, and glutathione (GSH) recycling, impacting their redox state and tumorigenic potential. Collectively, our data illustrate a previously unsuspected function of chromatin-bound MDM2 in cancer cell metabolism.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Montagem e Desmontagem da Cromatina , Cromatina/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Serina/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proliferação de Células , Cromatina/genética , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica , Glicina/metabolismo , Células HCT116 , Homeostase , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Nus , Mutação , Oxirredução , Estresse Oxidativo , Fosforilação , Ligação Proteica , Proteínas Proto-Oncogênicas c-mdm2/genética , Interferência de RNA , Hormônios Tireóideos/genética , Hormônios Tireóideos/metabolismo , Fatores de Tempo , Transcrição Gênica , Transfecção , Carga Tumoral , Proteína Supressora de Tumor p53/genética , Proteínas de Ligação a Hormônio da Tireoide
6.
Europace ; 25(4): 1467-1474, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36881780

RESUMO

AIMS: Patients with atrial fibrillation frequently experience sleep disorder breathing, and both conditions are highly prevalent in presence of heart failure (HF). We explored the association between the combination of an HF and a sleep apnoea (SA) index and the incidence of atrial high-rate events (AHRE) in patients with implantable defibrillators (ICDs). METHODS AND RESULTS: Data were prospectively collected from 411 consecutive HF patients with ICD. The IN-alert HF state was measured by the multi-sensor HeartLogic Index (>16), and the ICD-measured Respiratory Disturbance Index (RDI) was computed to identify severe SA. The endpoints were as follows: daily AHRE burden of ≥5 min, ≥6 h, and ≥23 h. During a median follow-up of 26 months, the time IN-alert HF state was 13% of the total observation period. The RDI value was ≥30 episodes/h (severe SA) during 58% of the observation period. An AHRE burden of ≥5 min/day was documented in 139 (34%) patients, ≥6 h/day in 89 (22%) patients, and ≥23 h/day in 68 (17%) patients. The IN-alert HF state was independently associated with AHRE regardless of the daily burden threshold: hazard ratios from 2.17 for ≥5 min/day to 3.43 for ≥23 h/day (P < 0.01). An RDI ≥ 30 episodes/h was associated only with AHRE burden ≥5 min/day [hazard ratio 1.55 (95% confidence interval: 1.11-2.16), P = 0.001]. The combination of IN-alert HF state and RDI ≥ 30 episodes/h accounted for only 6% of the follow-up period and was associated with high rates of AHRE occurrence (from 28 events/100 patient-years for AHRE burden ≥5 min/day to 22 events/100 patient-years for AHRE burden ≥23 h/day). CONCLUSIONS: In HF patients, the occurrence of AHRE is independently associated with the ICD-measured IN-alert HF state and RDI ≥ 30 episodes/h. The coexistence of these two conditions occurs rarely but is associated with a very high rate of AHRE occurrence. CLINICAL TRIAL REGISTRATION: URL: http://clinicaltrials.gov/Identifier: NCT02275637.


Assuntos
Fibrilação Atrial , Desfibriladores Implantáveis , Insuficiência Cardíaca , Síndromes da Apneia do Sono , Humanos , Desfibriladores Implantáveis/efeitos adversos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/terapia , Medição de Risco , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia
7.
Europace ; 25(9)2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37656991

RESUMO

AIMS: The HeartLogic Index combines data from multiple implantable cardioverter defibrillators (ICDs) sensors and has been shown to accurately stratify patients at risk of heart failure (HF) events. We evaluated and compared the performance of this algorithm during sinus rhythm and during long-lasting atrial fibrillation (AF). METHODS AND RESULTS: HeartLogic was activated in 568 ICD patients from 26 centres. We found periods of ≥30 consecutive days with an atrial high-rate episode (AHRE) burden <1 h/day and periods with an AHRE burden ≥20 h/day. We then identified patients who met both criteria during the follow-up (AHRE group, n = 53), to allow pairwise comparison of periods. For control purposes, we identified patients with an AHRE burden <1 h throughout their follow-up and implemented 2:1 propensity score matching vs. the AHRE group (matched non-AHRE group, n = 106). In the AHRE group, the rate of alerts was 1.2 [95% confidence interval (CI): 1.0-1.5]/patient-year during periods with an AHRE burden <1 h/day and 2.0 (95% CI: 1.5-2.6)/patient-year during periods with an AHRE-burden ≥20 h/day (P = 0.004). The rate of HF hospitalizations was 0.34 (95% CI: 0.15-0.69)/patient-year during IN-alert periods and 0.06 (95% CI: 0.02-0.14)/patient-year during OUT-of-alert periods (P < 0.001). The IN/OUT-of-alert state incidence rate ratio of HF hospitalizations was 8.59 (95% CI: 1.67-55.31) during periods with an AHRE burden <1 h/day and 2.70 (95% CI: 1.01-28.33) during periods with an AHRE burden ≥20 h/day. In the matched non-AHRE group, the rate of HF hospitalizations was 0.29 (95% CI: 0.12-0.60)/patient-year during IN-alert periods and 0.04 (95% CI: 0.02-0.08)/patient-year during OUT-of-alert periods (P < 0.001). The incidence rate ratio was 7.11 (95% CI: 2.19-22.44). CONCLUSION: Patients received more alerts during periods of AF. The ability of the algorithm to identify increased risk of HF events was confirmed during AF, despite a lower IN/OUT-of-alert incidence rate ratio in comparison with non-AF periods and non-AF patients. CLINICAL TRIAL REGISTRATION: http://clinicaltrials.gov/Identifier: NCT02275637.


Assuntos
Fibrilação Atrial , Desfibriladores Implantáveis , Insuficiência Cardíaca , Humanos , Algoritmos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/terapia , Átrios do Coração , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia
8.
J Nurs Care Qual ; 38(1): 47-54, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36066885

RESUMO

BACKGROUND: Carbapenem-resistant Enterobacteriaceae (CRE) is a worldwide urgent health problem. Hand hygiene (HH) is an effective intervention to reduce the spread of CRE. LOCAL PROBLEM: In 2017, an increase in the rate of health care-associated (HA) CRE colonization was observed in a large multiorgan transplant center in Italy. This study aimed to reduce the HA-CRE colonization rates by improving HH compliance. METHODS: A pre-/post-intervention project was conducted from November 2017 through December 2020. INTERVENTIONS: The DMAIC (Define, Measure, Analyze, Improve, and Control) framework was used to implement the HH Targeted Solution Tool (TST). RESULTS: Hand hygiene compliance increased from 49% to 76.9% after the Improve phase ( P = .0001), and to 81.9% after the second Control phase ( P = .0001). The rate of HA-CRE decreased from 24.9% to 5.6% ( P = .0001). CONCLUSIONS: Using the DMAIC framework to implement the TST can result in significant improvements in HH compliance and HA-CRE colonization rates.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecção Hospitalar , Infecções por Enterobacteriaceae , Higiene das Mãos , Humanos , Infecções por Enterobacteriaceae/prevenção & controle , Melhoria de Qualidade , Infecção Hospitalar/prevenção & controle
9.
Hum Mol Genet ; 29(8): 1353-1364, 2020 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-32280985

RESUMO

Mitochondrial Rho GTPase 1 (Miro1) protein is a well-known adaptor for mitochondrial transport and also regulates mitochondrial quality control and function. Furthermore, Miro1 was associated with mitochondrial-endoplasmic reticulum (ER) contact sites (MERCs), which are key regulators of cellular calcium homeostasis and the initiation of autophagy. Impairments of these mechanisms were linked to neurodegeneration in Parkinson's disease (PD). We recently revealed that PD fibroblasts harboring Miro1 mutations displayed dysregulations in MERC organization and abundance, affecting mitochondrial homeostasis and clearance. We hypothesize that mutant Miro1 impairs the function of MERCs and mitochondrial dynamics, altering neuronal homeostasis and integrity in PD. PD skin fibroblasts harboring the Miro1-R272Q mutation were differentiated into patient-derived neurons. Live-cell imaging and immunocytochemistry were used to study mitophagy and the organization and function of MERCs. Markers of autophagy or mitochondrial function were assessed by western blotting. Quantification of organelle juxtapositions revealed an increased number of MERCs in patient-derived neurons. Live-cell imaging results showed alterations of mitochondrial dynamics and increased sensitivity to calcium stress, as well as reduced mitochondrial clearance. Finally, western blot analysis indicated a blockage of the autophagy flux in Miro1-mutant neurons. Miro1-mutant neurons display altered ER-mitochondrial tethering compared with control neurons. This alteration likely interferes with proper MERC function, contributing to a defective autophagic flux and cytosolic calcium handling capacity. Moreover, mutant Miro1 affects mitochondrial dynamics in neurons, which may result in disrupted mitochondrial turnover and altered mitochondrial movement.


Assuntos
Retículo Endoplasmático/genética , Mitocôndrias/genética , Proteínas Mitocondriais/genética , Doença de Parkinson/genética , Proteínas rho de Ligação ao GTP/genética , Cálcio/metabolismo , Diferenciação Celular/genética , Citosol/metabolismo , Homeostase/genética , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Dinâmica Mitocondrial/genética , Mitofagia/genética , Neurônios/metabolismo , Neurônios/patologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia
10.
Mov Disord ; 37(7): 1405-1415, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35460111

RESUMO

BACKGROUND: Mutations in the E3 ubiquitin ligase parkin cause autosomal recessive Parkinson's disease (PD). Together with PTEN-induced kinase 1 (PINK1), parkin regulates the clearance of dysfunctional mitochondria. New mitochondria are generated through an interplay of nuclear- and mitochondrial-encoded proteins, and recent studies suggest that parkin influences this process at both levels. In addition, parkin was shown to prevent mitochondrial membrane permeability, impeding mitochondrial DNA (mtDNA) escape and subsequent neuroinflammation. However, parkin's regulatory roles independent of mitophagy are not well described in patient-derived neurons. OBJECTIVES: We sought to investigate parkin's role in preventing neuronal mtDNA dyshomeostasis, release, and glial activation at the endogenous level. METHODS: We generated induced pluripotent stem cell (iPSC)-derived midbrain neurons from PD patients with parkin (PRKN) mutations and healthy controls. Live-cell imaging, proteomic, mtDNA integrity, and gene expression analyses were employed to investigate mitochondrial biogenesis and genome maintenance. To assess neuroinflammation, we performed single-nuclei RNA sequencing in postmortem tissue and quantified interleukin expression in mtDNA/lipopolysaccharides (LPS)-treated iPSC-derived neuron-microglia co-cultures. RESULTS: Neurons from patients with PRKN mutations revealed deficits in the mitochondrial biogenesis pathway, resulting in mtDNA dyshomeostasis. Moreover, the energy sensor sirtuin 1, which controls mitochondrial biogenesis and clearance, was downregulated in parkin-deficient cells. Linking mtDNA disintegration to neuroinflammation, in postmortem midbrain with PRKN mutations, we confirmed mtDNA dyshomeostasis and detected an upregulation of microglia overexpressing proinflammatory cytokines. Finally, parkin-deficient neuron-microglia co-cultures elicited an enhanced immune response when exposed to mtDNA/LPS. CONCLUSIONS: Our findings suggest that parkin coregulates mitophagy, mitochondrial biogenesis, and mtDNA maintenance pathways, thereby protecting midbrain neurons from neuroinflammation and degeneration. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
DNA Mitocondrial , Doença de Parkinson , Ubiquitina-Proteína Ligases , DNA Mitocondrial/genética , Humanos , Inflamação/genética , Lipopolissacarídeos/farmacologia , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Proteômica , Ubiquitina-Proteína Ligases/deficiência , Ubiquitina-Proteína Ligases/genética
11.
Mov Disord ; 37(1): 80-94, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34637165

RESUMO

BACKGROUND: The etiology of Parkinson's disease (PD) is only partially understood despite the fact that environmental causes, risk factors, and specific gene mutations are contributors to the disease. Biallelic mutations in the phosphatase and tensin homolog (PTEN)-induced putative kinase 1 (PINK1) gene involved in mitochondrial homeostasis, vesicle trafficking, and autophagy are sufficient to cause PD. OBJECTIVES: We sought to evaluate the difference between controls' and PINK1 patients' derived neurons in their transition from neuroepithelial stem cells to neurons, allowing us to identify potential pathways to target with repurposed compounds. METHODS: Using two-dimensional and three-dimensional models of patients' derived neurons we recapitulated PD-related phenotypes. We introduced the usage of midbrain organoids for testing compounds. Using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein 9 (Cas9), we corrected the point mutations of three patients' derived cells. We evaluated the effect of the selected compound in a mouse model. RESULTS: PD patient-derived cells presented differences in their energetic profile, imbalanced proliferation, apoptosis, mitophagy, and a reduced differentiation efficiency to tyrosine hydroxylase positive (TH+) neurons compared to controls' cells. Correction of a patient's point mutation ameliorated the metabolic properties and neuronal firing rates as well as reversing the differentiation phenotype, and reducing the increased astrocytic levels. Treatment with 2-hydroxypropyl-ß-cyclodextrin increased the autophagy and mitophagy capacity of neurons concomitant with an improved dopaminergic differentiation of patient-specific neurons in midbrain organoids and ameliorated neurotoxicity in a mouse model. CONCLUSION: We show that treatment with a repurposed compound is sufficient for restoring the impaired dopaminergic differentiation of PD patient-derived cells. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Doença de Parkinson , 2-Hidroxipropil-beta-Ciclodextrina/metabolismo , Animais , Encéfalo/metabolismo , Neurônios Dopaminérgicos/metabolismo , Humanos , Camundongos , Neurônios/metabolismo , Organoides/metabolismo , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Fenótipo
12.
FASEB J ; 35(2): e21361, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33522017

RESUMO

Bcl-2-associated athanogen-6 (BAG6) is a nucleocytoplasmic shuttling protein involved in protein quality control. We previously demonstrated that BAG6 is essential for autophagy by regulating the intracellular localization of the acetyltransferase EP300, and thus, modifying accessibility to its substrates (TP53 in the nucleus and autophagy-related proteins in the cytoplasm). Here, we investigated BAG6 localization and function in the cytoplasm. First, we demonstrated that BAG6 is localized in the mitochondria. Specifically, BAG6 is expressed in the mitochondrial matrix under basal conditions, and translocates to the outer mitochondrial membrane after mitochondrial depolarization with carbonyl cyanide m-chlorophenyl hydrazine, a mitochondrial uncoupler that induces mitophagy. In SW480 cells, the deletion of BAG6 expression abrogates its ability to induce mitophagy and PINK1 accumulation. On the reverse, its ectopic expression in LoVo colon cancer cells, which do not express endogenous BAG6, reduces the size of the mitochondria, induces mitophagy, leads to the activation of the PINK1/PARKIN pathway and to the phospho-ubiquitination of mitochondrial proteins. Finally, BAG6 contains two LIR (LC3-interacting Region) domains specifically found in receptors for selective autophagy and responsible for the interaction with LC3 and for autophagosome selectivity. Site-directed mutagenesis showed that BAG6 requires wild-type LIRs domains for its ability to stimulate mitophagy. In conclusion, we propose that BAG6 is a novel mitophagy receptor or adaptor that induces PINK1/PARKIN signaling and mitophagy in a LIR-dependent manner.


Assuntos
Mitofagia , Chaperonas Moleculares/metabolismo , Proteínas Quinases/metabolismo , Transdução de Sinais , Sítios de Ligação , Linhagem Celular Tumoral , Humanos , Mitocôndrias/metabolismo , Chaperonas Moleculares/química , Chaperonas Moleculares/genética , Ligação Proteica , Ubiquitina-Proteína Ligases/metabolismo
13.
Pacing Clin Electrophysiol ; 45(8): 968-974, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35417055

RESUMO

BACKGROUND: It has been observed that the fourth-generation cryoballoon (CB4) ablation catheter increased the rate of acute real-time recordings of pulmonary vein isolation (PVI) during the ablation for the treatment of atrial fibrillation (AF). The aim of this analysis was to compare the long-term outcome results between patients treated with the CB4 and second-generation cryoballoon (CB2). METHODS: In total, 492 patients suffering from AF, underwent PVI ablation with either the CB2 or CB4 catheter within this examination of the 1STOP real-world Italian project and were included in the analysis. Specifically, 246 consecutive patients treated by CB4 were compared to 246 propensity-matched control patients who underwent PVI using CB2. RESULTS: When comparing the patient cohorts treated with CB2 versus CB4, acute success rate (99.6 ± 4.7% vs. 99.7 ± 3.6%, p = .949) and peri-procedural complications (3.7% vs.1.2%, p = .080) were similar in both groups, respectively. However, procedure time (100 vs.75 min, p < .001) and fluoroscopy duration (21 vs.17 min, p < .001) were all significantly lower in the CB4 treated patient cohort. At the 12-month follow-up, the freedom from AF recurrence after a 90-day blanking period was significant higher in the CB4 as compared with the CB2 group (93.3% vs.81.3%, p < .001). CONCLUSIONS: In summary, usage of the CB4 ablation catheter increased the rate of acute PVI recording capability and resulted in a higher rate of long-term PVI success, as demonstrated by the reduced rate of AF recurrence in comparison to the CB2 cohort at the 12-month follow-up period.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Criocirurgia , Veias Pulmonares , Ablação por Cateter/métodos , Catéteres , Criocirurgia/métodos , Humanos , Veias Pulmonares/cirurgia , Recidiva , Resultado do Tratamento
14.
Int J Mol Sci ; 23(6)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35328348

RESUMO

Ctr1 regulates copper uptake and its intracellular distribution. The first 14 amino acid sequence of the Ctr1 ectodomain Ctr1(1-14) encompasses the characteristic Amino Terminal Cu2+ and Ni2+ binding motif (ATCUN) as well as the bis-His binding motif (His5 and His6). We report a combined thermodynamic and spectroscopic (UV-vis, CD, EPR) study dealing with the formation of Cu2+ homobinuclear complexes with Ctr1(1-14), the percentage of which is not negligible even in the presence of a small Cu2+ excess and clearly prevails at a M/L ratio of 1.9. Ascorbate fails to reduce Cu2+ when bound to the ATCUN motif, while it reduces Cu2+ when bound to the His5-His6 motif involved in the formation of binuclear species. The histidine diade characterizes the second binding site and is thought to be responsible for ascorbate oxidation. Binding constants and speciation of Ag+ complexes with Ctr1(1-14), which are assumed to mimic Cu+ interaction with N-terminus of Ctr1(1-14), were also determined. A preliminary immunoblot assay evidences that the anti-Ctr1 extracellular antibody recognizes Ctr1(1-14) in a different way from the longer Ctr1(1-25) that encompasses a second His and Met rich domain.


Assuntos
Proteínas de Transporte de Cátions , Sequência de Aminoácidos , Sítios de Ligação , Proteínas de Transporte de Cátions/metabolismo , Cobre/química , Histidina/química
15.
Am Heart J ; 242: 103-114, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34508694

RESUMO

BACKGROUND: Cryoballoon ablation (CBA) as a first-line rhythm control strategy is superior to antiarrhythmic drugs (AADs) for preventing atrial fibrillation (AF) recurrence; the impact of first-line CBA on quality of life (QoL) and symptoms has not been well characterized. METHODS: Patients aged 18 to 75 with symptomatic paroxysmal AF naïve to rhythm control therapy were randomized (1:1) to CBA (Arctic Front Advance, Medtronic) or AAD (Class I or III). Symptoms and QoL were assessed at baseline, 1, 3, 6, 9, and 12 months using the EHRA classification and Atrial Fibrillation Effect on QualiTy-of-Life (AFEQT) and SF-36v2 questionnaires. Symptomatic palpitations were evaluated via patient diary. RESULTS: Overall, 107 patients were randomized to CBA and 111 to AAD; crossovers occurred in 9%. Larger improvements in the AFEQT summary, subscale and treatment satisfaction scores were observed at 12 months with CBA vs AAD (all P <0.05). At 12 months, the mean adjusted difference in the AFEQT summary score was 9.9 points higher in the CBA group (95% CI: 5.5 -14.2, P <0.001). Clinically important improvements in the SF-36 physical and mental component scores were observed at 12 months in both groups, with no significant between group differences at this timepoint. In the CBA vs AAD group, larger improvements in EHRA class were observed at 6, 9 and 12 months (P <0.05) and the incidence rate of symptomatic palpitations was lower (4.6 vs 15.2 days/year post-blanking; IRR: 0.30, P <0.001). CONCLUSIONS: In patients with symptomatic AF, first-line CBA was superior to AAD for improving AF-specific QoL and symptoms. TRIAL REGISTRATION: ClinicalTrials.gov number: NCT01803438.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Criocirurgia , Adolescente , Adulto , Idoso , Antiarrítmicos/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/cirurgia , Humanos , Pessoa de Meia-Idade , Qualidade de Vida , Resultado do Tratamento , Adulto Jovem
16.
Chemistry ; 27(70): 17669-17675, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34637566

RESUMO

Series of lanthanide-containing metallic coordination complexes are frequently presented as structurally analogous, due to the similar chemical and coordinative properties of the lanthanides. In the case of chiral (LnIII [15-MC Cu II N(L-pheHA) -5])3+ metallacrowns (MCs), which are well established supramolecular hosts, the formation of dimers templated by a dicarboxylate guest (muconate) in solution of neutral pH is herein shown to have a unique dependence on the identity of the MC's central lanthanide. Calorimetric data and nuclear magnetic resonance diffusion studies demonstrate that MCs containing larger or smaller lanthanides as the central metal only form monomeric host-guest complexes whereas analogues with intermediate lanthanides (for example, Eu, Gd, Dy) participate in formation of dimeric host-guest-host compartments. The driving force for the dimerization event across the series is thought to be a competition between formation of highly stable MCs (larger lanthanides) and optimally linked bridging guests (smaller lanthanides).


Assuntos
Complexos de Coordenação , Elementos da Série dos Lantanídeos , Calorimetria , Dimerização , Concentração de Íons de Hidrogênio
17.
FASEB J ; 34(3): 3616-3630, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31957088

RESUMO

Mitochondria are considered as the power-generating units of the cell due to their key role in energy metabolism and cell signaling. However, mitochondrial components could be found in the extracellular space, as fragments or encapsulated in vesicles. In addition, this intact organelle has been recently reported to be released by platelets exclusively in specific conditions. Here, we demonstrate for the first time, that blood preparation with resting platelets, contains whole functional mitochondria in normal physiological state. Likewise, we show, that normal and tumor cultured cells are able to secrete their mitochondria. Using serial centrifugation or filtration followed by polymerase chain reaction-based methods, and Whole Genome Sequencing, we detect extracellular full-length mitochondrial DNA in particles over 0.22 µm holding specific mitochondrial membrane proteins. We identify these particles as intact cell-free mitochondria using fluorescence-activated cell sorting analysis, fluorescence microscopy, and transmission electron microscopy. Oxygen consumption analysis revealed that these mitochondria are respiratory competent. In view of previously described mitochondrial potential in intercellular transfer, this discovery could greatly widen the scope of cell-cell communication biology. Further steps should be developed to investigate the potential role of mitochondria as a signaling organelle outside the cell and to determine whether these circulating units could be relevant for early detection and prognosis of various diseases.


Assuntos
DNA Mitocondrial/genética , Mitocôndrias/metabolismo , Western Blotting , Linhagem Celular Tumoral , Genoma Mitocondrial/genética , Humanos , Cinética
18.
Europace ; 23(7): 1033-1041, 2021 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-33728429

RESUMO

AIMS: Treatment guidelines for patients with atrial fibrillation (AF) suggest that patients should be managed with an antiarrhythmic drug (AAD) before undergoing catheter ablation (CA). This study evaluated whether pulmonary vein isolation employing cryoballoon CA is superior to AAD therapy for the prevention of atrial arrhythmia (AA) recurrence in rhythm control naive patients with paroxysmal AF (PAF). METHODS AND RESULTS: A total of 218 treatment naive patients with symptomatic PAF were randomized (1 : 1) to cryoballoon CA (Arctic Front Advance, Medtronic) or AAD (Class I or III) and followed for 12 months. The primary endpoint was ≥1 episode of recurrent AA (AF, atrial flutter, or atrial tachycardia) >30 s after a prespecified 90-day blanking period. Secondary endpoints included the rate of serious adverse events (SAEs) and recurrence of symptomatic palpitations (evaluated via patient diaries). Freedom from AA was achieved in 82.2% of subjects in the cryoballoon arm and 67.6% of subjects in the AAD arm (HR = 0.48, P = 0.01). There were no group differences in the time-to-first (HR = 0.76, P = 0.28) or overall incidence [incidence rate ratio (IRR)=0.79, P = 0.28] of SAEs. The incidence rate of symptomatic palpitations was lower in the cryoballoon (7.61 days/year) compared with the AAD arm (18.96 days/year; IRR = 0.40, P < 0.001). CONCLUSIONS: Cryoballoon CA was superior to AAD therapy, significantly reducing AA recurrence in treatment naive patients with PAF. Additionally, cryoballoon CA was associated with lower symptom recurrence and a similar rate of SAEs compared with AAD therapy.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Criocirurgia , Veias Pulmonares , Antiarrítmicos/efeitos adversos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Criocirurgia/efeitos adversos , Humanos , Veias Pulmonares/cirurgia , Recidiva , Resultado do Tratamento
19.
Cardiology ; 146(5): 547-555, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34233326

RESUMO

AIMS: Using data from the nationwide prospective START registry that enrolled a large cohort of patients with chronic coronary syndromes (CCS), we aimed to investigate whether the presence of diabetes mellitus (DM) and pre-DM independently affected the risk of cardiovascular events at 1-year follow-up. METHODS: We assessed the impact of DM and pre-DM on all-cause mortality and a composite of all-cause mortality and hospitalization for cardiovascular causes at 1-year follow-up. RESULTS: Among the 3,778 patients with available fasting plasma glucose data at study entry, 37% were classified as DM, 25% as pre-DM, and 38% as no DM. At 1 year, patients with DM had higher rates of all-cause death (p = 0.004) and death/cardiovascular hospitalization (p = 0.003) than those with pre-DM or without DM. Conversely, no significant differences in the adverse event rate were found between patients with pre-DM and those without DM. At unadjusted Cox analysis, DM resulted as a predictor of both death for any cause (hazard ratio [HR]: 2.41; 95% confidence intervals [CI]: 1.34-4.34; p = 0.003) and all-cause death/hospitalization for cardiovascular causes (HR: 1.29; 95% CI: 1.02-1.62; p = 0.03). However, DM did not result as an independent predictor of either endpoint at multivariate analysis. CONCLUSIONS: The risk of 1-year major events among patients with CCS and pre-DM is comparable to that of patients with CCS and normoglycemic status and is lower than that of patients with DM.


Assuntos
Estado Pré-Diabético , Humanos , Prognóstico , Estudos Prospectivos , Sistema de Registros , Síndrome
20.
Pacing Clin Electrophysiol ; 44(2): 306-317, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33372267

RESUMO

BACKGROUND: Pulmonary veins isolation (PVI) by cryoballoon (CB) ablation is marginally represented in clinical studies in obese patients. The aim of this analysis was to evaluate the safety and efficacy of CB-PVI in a large cohort of overweight and obese patients from the 1STOP project. METHODS: From 2012 to 2018, 2048 patients with atrial fibrillation (AF) (70% male, 59 ± 11 years; 75% paroxysmal AF) underwent index CB-PVI. The patient data were separated into three cohorts for statistical evaluation, including: normal weight (body mass index [BMI] < 25 kg/m2 ), overweight (BMI = 25-30 kg/m2 ), and obese patients (BMI > 30 kg/m2 ). RESULTS: Out of 2048 patients, 693 (34%) patients had a BMI < 25 and were deemed as normal. There were 944 (46%) patients categorized as overweight (BMI = 25-30) and 411 (20%) as obese (BMI > 30). Overweight or obese patients were more often in persistent AF, had more frequently hypertension and diabetes, had higher CHA2 DS2 -VASc score, and had a number of failed antiarrhythmic drug (AAD). Periprocedural complication rates were similar among the three cohorts. The 12-month freedom from AF recurrence was 76.4% in the normal BMI group as compared to 79.2% in the overweight and 73.5% in the obese group (p = .35). However, 48% of overweight patients were on AAD treatment during the follow-up. By multivariate analysis, BMI was not a predictor for AF recurrence following the index CB-PVI. CONCLUSION: CB-PVI in obese patients is a safe procedure. Increased BMI (either moderate or severe) does not seem to be associated with a worse outcome or to a different rate of AAD discontinuation at 12 months.


Assuntos
Fibrilação Atrial/complicações , Fibrilação Atrial/cirurgia , Criocirurgia , Obesidade/complicações , Veias Pulmonares/cirurgia , Idoso , Criocirurgia/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
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