RESUMO
Neuroglobin, a member of the globin superfamily, is abundant in the brain, retina, and cerebellum of mammals and localizes to mitochondria. The protein exhibits neuroprotective capacities by participating in electron transfer, oxygen supply, and protecting against oxidative stress. Our objective was to determine whether neuroglobin overexpression can be used to treat neurological disorders. We chose Harlequin mice, which harbor a retroviral insertion in the first intron of the apoptosis-inducing factor gene resulting in the depletion of the corresponding protein essential for mitochondrial biogenesis. Consequently, Harlequin mice display degeneration of the cerebellum and suffer from progressive blindness and ataxia. Cerebellar ataxia begins in Harlequin mice at the age of 4 months and is characterized by neuronal cell disappearance, bioenergetics failure, and motor and cognitive impairments, which aggravated with aging. Mice aged 2 months received adeno-associated viral vectors harboring the coding sequence of neuroglobin or apoptosis-inducing factor in both cerebellar hemispheres. Six months later, Harlequin mice exhibited substantial improvements in motor and cognitive skills; probably linked to the preservation of respiratory chain function, Purkinje cell numbers and connectivity. Thus, without sharing functional properties with apoptosis-inducing factor, neuroglobin was efficient in reducing ataxia in Harlequin mice.
Assuntos
Ataxia Cerebelar , Cerebelo , Globinas , Mitocôndrias , Proteínas do Tecido Nervoso , Neuroglobina , Animais , Camundongos , Fator de Indução de Apoptose/metabolismo , Fator de Indução de Apoptose/genética , Ataxia Cerebelar/metabolismo , Ataxia Cerebelar/genética , Ataxia Cerebelar/terapia , Cerebelo/metabolismo , Dependovirus/genética , Modelos Animais de Doenças , Expressão Gênica , Terapia Genética/métodos , Vetores Genéticos/genética , Vetores Genéticos/administração & dosagem , Globinas/metabolismo , Globinas/genética , Homeostase , Mitocôndrias/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/genética , Neuroglobina/metabolismo , Neurônios/metabolismoRESUMO
BACKGROUND: Type 2 diabetes (T2D) is a frequent comorbidity encountered in patients with severe aortic stenosis (AS), leading to an adverse left ventricular (LV) remodeling and dysfunction. Metabolic alterations have been suggested as contributors of the deleterious effect of T2D on LV remodeling and function in patients with severe AS, but so far, the underlying mechanisms remain unclear. Mitochondria play a central role in the regulation of cardiac energy metabolism. OBJECTIVES: We aimed to explore the mitochondrial alterations associated with the deleterious effect of T2D on LV remodeling and function in patients with AS, preserved ejection fraction, and no additional heart disease. METHODS: We combined an in-depth clinical, biological and echocardiography phenotype of patients with severe AS, with (n = 34) or without (n = 50) T2D, referred for a valve replacement, with transcriptomic and histological analyses of an intra-operative myocardial LV biopsy. RESULTS: T2D patients had similar AS severity but displayed worse cardiac remodeling, systolic and diastolic function than non-diabetics. RNAseq analysis identified 1029 significantly differentially expressed genes. Functional enrichment analysis revealed several T2D-specific upregulated pathways despite comorbidity adjustment, gathering regulation of inflammation, extracellular matrix organization, endothelial function/angiogenesis, and adaptation to cardiac hypertrophy. Downregulated gene sets independently associated with T2D were related to mitochondrial respiratory chain organization/function and mitochondrial organization. Generation of causal networks suggested a reduced Ca2+ signaling up to the mitochondria, with the measured gene remodeling of the mitochondrial Ca2+ uniporter in favor of enhanced uptake. Histological analyses supported a greater cardiomyocyte hypertrophy and a decreased proximity between the mitochondrial VDAC porin and the reticular IP3-receptor in T2D. CONCLUSIONS: Our data support a crucial role for mitochondrial Ca2+ signaling in T2D-induced cardiac dysfunction in severe AS patients, from a structural reticulum-mitochondria Ca2+ uncoupling to a mitochondrial gene remodeling. Thus, our findings open a new therapeutic avenue to be tested in animal models and further human cardiac biopsies in order to propose new treatments for T2D patients suffering from AS. TRIAL REGISTRATION: URL: https://www. CLINICALTRIALS: gov ; Unique Identifier: NCT01862237.
Assuntos
Estenose da Valva Aórtica , Sinalização do Cálcio , Diabetes Mellitus Tipo 2 , Perfilação da Expressão Gênica , Mitocôndrias Cardíacas , Índice de Gravidade de Doença , Transcriptoma , Função Ventricular Esquerda , Remodelação Ventricular , Humanos , Estenose da Valva Aórtica/metabolismo , Estenose da Valva Aórtica/genética , Estenose da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/patologia , Masculino , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Feminino , Idoso , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/complicações , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/genética , Disfunção Ventricular Esquerda/metabolismo , Disfunção Ventricular Esquerda/diagnóstico por imagemRESUMO
Diabetic cardiomyopathy (DCM) is a leading complication in type 2 diabetes patients. Recently, we have shown that the reticulum-mitochondria Ca2+ uncoupling is an early and reversible trigger of the cardiac dysfunction in a diet-induced mouse model of DCM. Metformin is a first-line antidiabetic drug with recognized cardioprotective effect in myocardial infarction. Whether metformin could prevent the progression of DCM remains not well understood. We therefore investigated the effect of a chronic 6-week metformin treatment on the reticulum-mitochondria Ca2+ coupling and the cardiac function in our high-fat high-sucrose diet (HFHSD) mouse model of DCM. Although metformin rescued the glycemic regulation in the HFHSD mice, it did not preserve the reticulum-mitochondria Ca2+ coupling either structurally or functionally. Metformin also did not prevent the progression towards cardiac dysfunction, i.e., cardiac hypertrophy and strain dysfunction. In summary, despite its cardioprotective role, metformin is not sufficient to delay the progression to early DCM.
Assuntos
Diabetes Mellitus Tipo 2 , Cardiomiopatias Diabéticas , Insuficiência Cardíaca , Metformina , Animais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/etiologia , Modelos Animais de Doenças , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/etiologia , Humanos , Metformina/farmacologia , Metformina/uso terapêutico , Camundongos , Volume SistólicoRESUMO
Mitochondrial diseases are among the most prevalent groups of inherited neurological disorders, affecting up to 1 in 5000 adults. Despite the progress achieved on the identification of gene mutations causing mitochondrial pathologies, they cannot be cured so far. Harlequin mice, a relevant model of mitochondrial pathology due to apoptosis inducing factor depletion, suffer from progressive disappearance of retinal ganglion cells leading to optic neuropathy. In our previous work, we showed that administering adeno-associated virus encompassing the coding sequences for neuroglobin, (a neuroprotective molecule belonging to the globin family) or apoptosis-inducing factor, before neurodegeneration onset, prevented retinal ganglion cell loss and preserved visual function. One of the challenges to develop an effective treatment for optic neuropathies is to consider that by the time patients become aware of their handicap, a large amount of nerve fibers has already disappeared. Gene therapy was performed in Harlequin mice aged between 4 and 5 months with either a neuroglobin or an apoptosis-inducing factor vector to determine whether the increased abundance of either one of these proteins in retinas could preserve visual function at this advanced stage of the disease. We demonstrated that gene therapy, by preserving the connectivity of transduced retinal ganglion cells and optic nerve bioenergetics, results in the enhancement of visual cortex activity, ultimately rescuing visual impairment. This study demonstrates that: (a) An increased abundance of neuroglobin functionally overcomes apoptosis-inducing factor absence in Harlequin mouse retinas at a late stage of neuronal degeneration; (b) The beneficial effect for visual function could be mediated by neuroglobin localization to the mitochondria, thus contributing to the maintenance of the organelle homeostasis.
Assuntos
Fator de Indução de Apoptose/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Neuroglobina/genética , Atrofia Óptica/metabolismo , Nervo Óptico/metabolismo , Células Ganglionares da Retina/metabolismo , Acuidade Visual/genética , Córtex Visual/metabolismo , Animais , Progressão da Doença , Terapia Genética , Camundongos , Atrofia Óptica/patologia , Atrofia Óptica/fisiopatologia , Nervo Óptico/patologia , Nervo Óptico/fisiopatologia , Células Ganglionares da Retina/patologia , Córtex Visual/patologia , Vias VisuaisRESUMO
BACKGROUND AND AIM OF THE STUDY: Data about the beating heart (BH) technique for isolated tricuspid valve (TV) surgery compared to the arrested heart (AH) technique are sparse. We compared the outcomes of isolated TV surgery between BH and AH technique. METHODS: We performed an observational analysis of our database of isolated TV surgery. Patients were divided into two groups according to whether surgery was performed without (BH group) or with (AH group) aortic cross-clamping and cardioplegic arrest. The primary endpoint was survival to hospital discharge. Risk factors for in-hospital mortality were searched with multivariate analyses. We undertook further comparisons after propensity-score matching. RESULTS: From January 2007 to December 2017, we performed 82 isolated TV surgery (BH group, n = 47, 57.3%; AH group, n = 35, 42.7%). The mean age was 59.1 years, 56.1% were female. BH group patients were older (61.8 vs. 55.4 years; p = .035), had greater impaired renal function (glomerular filtration rate, 61.1 vs. 74.6 ml/min; p = .012), were more frequently operated for secondary TR (61.7 vs. 31.4%; p = .008), underwent more frequently a reoperation (53.2 vs. 28.6%; p = .042) and exhibited a higher surgical risk (EuroSCORE II, 3.92 vs. 2.50%; p = .013). In-hospital mortality was not different between both groups, either considering unmatched (BH = 10.6 vs. AH = 5.7%; OR = 1.96, 95% confidence interval [CI] = 0.36-10.77) or matched populations (BH = 10.6 vs. AH = 6.4%; OR = 1.89, 95% CI = 0.36-9.97). Age was the only predictor of in-hospital mortality. CONCLUSIONS: The BH technique showed comparable outcomes to the AH technique for isolated TV surgery despite a higher risk profile.
Assuntos
Procedimentos Cirúrgicos Cardíacos , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Tricúspide , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/cirurgiaRESUMO
Type 2 diabetic cardiomyopathy features Ca2+ signaling abnormalities, notably an altered mitochondrial Ca2+ handling. We here aimed to study if it might be due to a dysregulation of either the whole Ca2+ homeostasis, the reticulum-mitochondrial Ca2+ coupling, and/or the mitochondrial Ca2+ entry through the uniporter. Following a 16-week high-fat high-sucrose diet (HFHSD), mice developed cardiac insulin resistance, fibrosis, hypertrophy, lipid accumulation, and diastolic dysfunction when compared to standard diet. Ultrastructural and proteomic analyses of cardiac reticulum-mitochondria interface revealed tighter interactions not compatible with Ca2+ transport in HFHSD cardiomyocytes. Intramyocardial adenoviral injections of Ca2+ sensors were performed to measure Ca2+ fluxes in freshly isolated adult cardiomyocytes and to analyze the direct effects of in vivo type 2 diabetes on cardiomyocyte function. HFHSD resulted in a decreased IP3R-VDAC interaction and a reduced IP3-stimulated Ca2+ transfer to mitochondria, with no changes in reticular Ca2+ level, cytosolic Ca2+ transients, and mitochondrial Ca2+ uniporter function. Disruption of organelle Ca2+ exchange was associated with decreased mitochondrial bioenergetics and reduced cell contraction, which was rescued by an adenovirus-mediated expression of a reticulum-mitochondria linker. An 8-week diet reversal was able to restore cardiac insulin signaling, Ca2+ transfer, and cardiac function in HFHSD mice. Therefore, our study demonstrates that the reticulum-mitochondria Ca2+ miscoupling may play an early and reversible role in the development of diabetic cardiomyopathy by disrupting primarily the mitochondrial bioenergetics. A diet reversal, by counteracting the MAM-induced mitochondrial Ca2+ dysfunction, might contribute to restore normal cardiac function and prevent the exacerbation of diabetic cardiomyopathy.
Assuntos
Sinalização do Cálcio , Cálcio/metabolismo , Cardiomiopatias Diabéticas/metabolismo , Retículo Endoplasmático/metabolismo , Mitocôndrias Cardíacas/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Canais de Cálcio/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 2/complicações , Cardiomiopatias Diabéticas/dietoterapia , Cardiomiopatias Diabéticas/etiologia , Cardiomiopatias Diabéticas/patologia , Dieta Hiperlipídica , Sacarose Alimentar , Retículo Endoplasmático/patologia , Metabolismo Energético , Acoplamento Excitação-Contração , Inositol 1,4,5-Trifosfato/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Resistência à Insulina , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias Cardíacas/patologia , Proteínas Mitocondriais/metabolismo , Miócitos Cardíacos/patologia , Canal de Ânion 1 Dependente de Voltagem/metabolismoRESUMO
Despite promising experimental studies and encouraging proof-of-concept clinical trials, interventions aimed at limiting infarct size have failed to improve clinical outcomes in patients with ST-elevation myocardial infarction (STEMI). Our objective was to examine whether variables (cardiovascular risk factors, comorbidities, post-procedural variables, cotreatments) might be associated with clinical outcomes in STEMI patients independently from infarct size reduction. The present study was based on a post hoc analysis of the CIRCUS trial database (Clinicaltrials.gov NCT01502774) that assessed the clinical benefit of a single intravenous bolus of cyclosporine in 969 patients with anterior STEMI. Since cyclosporine had no detectable effect on clinical outcomes as well as on any measured variable, we here considered the whole study population as one group. Multivariate analysis was performed to address the respective weight of infarct size and variables in clinical outcomes. Multivariate analysis revealed that several variables (including gender, hypertension, renal dysfunction, TIMI flow grade post-PCI < 3, and treatment administered after PCI with betablockers and angiotensin-converting enzyme inhibitors) had per se a significant influence on the occurrence of [death or hospitalization for heart failure] at 1 year. The relative weight of infarct size and variables on the composite endpoint of [death or hospitalization for heart failure] at 1 year was 18% and 82%, respectively. Several variables contribute strongly to the clinical outcomes of STEMI patients suggesting that cardioprotective strategy might not only focus on infarct size reduction.
Assuntos
Insuficiência Cardíaca/etiologia , Miocárdio/patologia , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Idoso , Europa (Continente)/epidemiologia , Feminino , Insuficiência Cardíaca/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Infarto do Miocárdio com Supradesnível do Segmento ST/patologia , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Remodelação VentricularRESUMO
AIM: This study was to characterise respiratory and nonrespiratory sleep disorders in obese children and evaluate the diagnostic and therapeutic impact of a specific sleep consultation. METHODS: A descriptive study was conducted in obese French children who received multidisciplinary care management from the hospital centre for paediatric obesity in Bordeaux. This followed a specific sleep consultation between 2007 and 2015, because their paediatrician had identified symptoms suggestive of sleep disorders. RESULTS: The sleep specialist confirmed the presence of a sleep disorder in 98.4% of the 128 obese children, with a mean age of 12.1 ± 3.2 years. These included respiratory sleep disorders, hypersomnolence, insomnia and circadian rhythm sleep-wake disorders. Polysomnography revealed that 46.1% had respiratory sleep disorders and 24.2% had obstructive sleep apnoea syndrome (OSAS). Just under half (47.6%) were referred to an otorhinolaryngologist for sleep care management, 30.5% were referred to an orthodontist, 17.9% had melatonin treatment and 13.3% received continuous positive airway pressure ventilation. CONCLUSION: Sleep disorders in obese children were not limited to respiratory sleep disorders including OSAS. A systematic specific consultation with a sleep specialist is essential for the diagnosis and care of such children and would be beneficial when treating paediatric obesity.
Assuntos
Obesidade Infantil/complicações , Transtornos do Sono-Vigília/diagnóstico , Transtornos do Sono-Vigília/epidemiologia , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Pressão Positiva Contínua nas Vias Aéreas , Feminino , França , Humanos , Masculino , Obesidade Infantil/fisiopatologia , Polissonografia , Transtornos do Sono-Vigília/terapiaRESUMO
Protein palmitoylation regulates many aspects of cell function and is carried out by acyl transferases that contain zf-DHHC motifs. The in vivo physiological function of protein palmitoylation is largely unknown. Here we generated mice deficient in the acyl transferase Aph2 (Ablphilin 2 or zf-DHHC16) and demonstrated an essential role for Aph2 in embryonic/postnatal survival, eye development, and heart development. Aph2(-/-) embryos and pups showed cardiomyopathy and cardiac defects including bradycardia. We identified phospholamban, a protein often associated with human cardiomyopathy, as an interacting partner and a substrate of Aph2. Aph2-mediated palmitoylation of phospholamban on cysteine 36 differentially alters its interaction with PKA and protein phosphatase 1 α, augmenting serine 16 phosphorylation, and regulates phospholamban pentamer formation. Aph2 deficiency results in phospholamban hypophosphorylation, a hyperinhibitory form. Ablation of phospholamban in Aph2(-/-) mice histologically and functionally alleviated the heart defects. These findings establish Aph2 as a critical in vivo regulator of cardiac function and reveal roles for protein palmitoylation in the development of other organs including eyes.
Assuntos
Aciltransferases/fisiologia , Cardiomiopatias/etiologia , Proteínas de Transporte/fisiologia , Animais , Células COS , Proteínas de Ligação ao Cálcio/metabolismo , Chlorocebus aethiops , Ecocardiografia , Olho/embriologia , Lipoilação , Camundongos , FosforilaçãoRESUMO
Myocardial conditioning is an endogenous cardioprotective phenomenon that profoundly limits infarct size in experimental models. The current challenge is to translate this paradigm from the laboratory to the clinic. Accordingly, our goal in this review is to provide a critical summary of the progress toward, opportunities for, and caveats to, the successful clinical translation of postconditioning and remote conditioning, the 2 conditioning strategies considered to have the broadest applicability for real-world patient care. In the majority of phase II studies published to date, postconditioning evoked a ≈35% reduction of infarct size in ST-segment-elevation myocardial infarction patients. Essential criteria for the successful implementation of postconditioning include the appropriate choice of patients (ie, those with large risk regions and negligible collateral flow), timely application of the postconditioning stimulus (immediately on reperfusion), together with proper choice of end points (infarct size, with concomitant assessment of risk region). Remote conditioning has been applied in planned ischemic events (including cardiac surgery and elective percutaneous coronary intervention) and in ST-segment-elevation myocardial infarction patients during hospital transport. Controversies with regard to efficacy have emerged, particularly among surgical trials. These disparate outcomes in all likelihood reflect the remarkable heterogeneity within and among studies, together with a deficit in our understanding of the impact of these variations on the infarct-sparing effect of remote conditioning. Ongoing phase III trials will provide critical insight into the future role of postconditioning and remote conditioning as clinically relevant cardioprotective strategies.
Assuntos
Precondicionamento Isquêmico Miocárdico/tendências , Infarto do Miocárdio/prevenção & controle , Pesquisa Translacional Biomédica/tendências , Animais , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Modelos Animais de Doenças , Humanos , Fatores de TempoRESUMO
Neuroglobin (NGB) is considered as an endogenous neuroprotective molecule against stroke, since the protein alleviates the adverse effects of hypoxic and ischemic insults. We previously demonstrated the functional link between NGB and mitochondria since it is required for respiratory chain function. Thus, here, we evaluated the relevance of this effect in the Harlequin (Hq) mouse strain, which exhibits retinal ganglion cell (RGC) loss and optic atrophy due to a respiratory chain complex I (CI) defect. A twofold decrease of NGB amounts was observed in Hq retinas. We constructed a recombinant adeno-associated virus which combines to the mouse NGB open reading frame, its 5' and 3'UTR, for guarantying mRNA stability and translation capacity. The vector was administrated intravitreally to Hq mice and NGB expression was stable for up to 7 months without negative effect on retinal architecture or function. On the contrary, RGCs and their axons were substantially preserved from degeneration; consequently, CI activity in optic nerves was protected conferring improvements in vision. Hence, we established that NGB prevents respiratory chain impairment, therefore, protecting visual function otherwise compromised by mitochondrial energetic failure.
Assuntos
Complexo I de Transporte de Elétrons/deficiência , Globinas/genética , Proteínas do Tecido Nervoso/genética , Atrofia Óptica/prevenção & controle , Atrofia Óptica/terapia , Células Ganglionares da Retina/metabolismo , Animais , Axônios/metabolismo , Axônios/patologia , Dependovirus/genética , Modelos Animais de Doenças , Terapia Genética , Vetores Genéticos/administração & dosagem , Gliose/patologia , Gliose/prevenção & controle , Globinas/metabolismo , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Neuroglobina , Atrofia Óptica/genética , Atrofia Óptica/patologia , Células Ganglionares da Retina/patologiaRESUMO
OBJECTIVE: The objective of the present study was to describe changes in overweight and obesity prevalence and eating habits among 7.5-10.5-year-old children in Aquitaine (France) between 2004 and 2008, and to assess how the programme 'Nutrition, Prevention and Health of children and teenagers in Aquitaine' implemented in 2004 may have impacted these changes. DESIGN: Two cross-sectional studies were conducted in two samples of children: the 'before programme' sample during the school year 2004/2005 and the 'after programme' sample during the school year 2008/2009. Settings Data were collected on gender, age, weight, height, area of residence (rural/urban) and socio-economic status of the school (non-low socio-economic/low socio-economic). Multivariate analyses were used to assess the effect of the regional programme intervention on the evolution of overweight and obesity prevalence and eating habits independently. SUBJECTS: The 'before programme' sample included 1836 children from 163 schools during the school year 2004/2005 and the 'after programme' sample included 3483 children from 210 schools during the school year 2008/2009. RESULTS: After adjustment of the model for age, residential area and socio-economic status of the area of residence, the prevalence of overweight including obesity (OR = 1.05; 95% CI 0.89, 1.23, P = 0.56) and of obesity (OR = 0.99; 95% CI 0.71, 1.39, P = 0.96) was found to have stabilized and eating habits had improved: intake of light afternoon meals had increased (OR = 1.38; 95% CI 1.13, 1.69, P = 0.002) while snacking in the morning (OR = 0.50; 95 % CI 0.45, 0.57, P < 0.001) and nibbling (OR = 0.81; 95% CI 0.70, 0.93, P < 0.001) had decreased. CONCLUSIONS: These results encourage the promotion and implementation of regional and national interventions among children regarding their eating habits in order to stabilize or decrease the prevalence of overweight.
Assuntos
Índice de Massa Corporal , Peso Corporal , Dieta , Comportamento Alimentar , Obesidade/prevenção & controle , Criança , Estudos Transversais , Feminino , França/epidemiologia , Humanos , Masculino , Análise Multivariada , Obesidade/epidemiologia , Razão de Chances , Sobrepeso/epidemiologia , Sobrepeso/prevenção & controle , Prevalência , Avaliação de Programas e Projetos de Saúde , Instituições Acadêmicas , LanchesRESUMO
The functional integrity of the central nervous system relies on complex mechanisms in which the mitochondria are crucial actors because of their involvement in a multitude of bioenergetics and biosynthetic pathways. Mitochondrial diseases are among the most prevalent groups of inherited neurological disorders, affecting up to 1 in 5000 adults and despite considerable efforts around the world there is still limited curative treatments. Harlequin mice correspond to a relevant model of recessive X-linked mitochondrial disease due to a proviral insertion in the first intron of the Apoptosis-inducing factor gene, resulting in an almost complete depletion of the corresponding protein. These mice exhibit progressive degeneration of the retina, optic nerve, cerebellum, and cortical regions leading to irremediable blindness and ataxia, reminiscent of what is observed in patients suffering from mitochondrial diseases. We evaluated the progression of cerebellar degeneration in Harlequin mice, especially for Purkinje cells and its relationship with bioenergetics failure and behavioral damage. For the first time to our knowledge, we demonstrated that Harlequin mice display cognitive and emotional impairments at early stage of the disease with further deteriorations as ataxia aggravates. These functions, corresponding to higher-order cognitive processing, have been assigned to a complex network of reciprocal connections between the cerebellum and many cortical areas which could be dysfunctional in these mice. Consequently, Harlequin mice become a suitable experimental model to test innovative therapeutics, via the targeting of mitochondria which can become available to a large spectrum of neurological diseases.
Assuntos
Fator de Indução de Apoptose , Disfunção Cognitiva , Modelos Animais de Doenças , Metabolismo Energético , Células de Purkinje , Animais , Células de Purkinje/metabolismo , Células de Purkinje/patologia , Camundongos , Fator de Indução de Apoptose/metabolismo , Fator de Indução de Apoptose/genética , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Disfunção Cognitiva/genética , Masculino , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Doenças Mitocondriais/metabolismo , Doenças Mitocondriais/patologia , Doenças Mitocondriais/genética , Camundongos Endogâmicos C57BLRESUMO
Neuroglobin is a member of the globin superfamily expressed in vertebrate brain and retina. The protein is thought to be involved in neuronal protection from hypoxia or oxidative stress and could represent a key element of Alzheimer disease pathogenesis. Our aim was to determine whether neuroglobin could be directly associated with mitochondrial metabolism and integrity. We identified three different forms of neuroglobin in the retina, varying in their apparent molecular masses; all forms are abundant in mitochondrial fractions. This indicates that a significant fraction of the protein localizes within the organelle either in the matrix or in the matrix side of the inner membrane. Since neuroglobin was especially abundant in the ganglion cell layer, we transduced retinal ganglion cells with an anti-neuroglobin short hairpin RNA using in vivo electroporation. Neuroglobin knockdown leads to reduced activities of respiratory chain complexes I and III, degeneration of retinal ganglion cells, and impairment of visual function. The deleterious effect on cell survival was confirmed in primary retinal ganglion cells subjected to inhibition of neuroglobin expression. Hence, neuroglobin should be considered as a novel mitochondrial protein involved in respiratory chain function which is essential for retinal ganglion cell integrity.
Assuntos
Transporte de Elétrons/fisiologia , Globinas/metabolismo , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Células Ganglionares da Retina/fisiologia , Animais , Western Blotting , Células Cultivadas , Angiofluoresceinografia , Globinas/antagonistas & inibidores , Globinas/genética , Masculino , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/genética , Neuroglobina , Neurônios/citologia , Nervo Óptico/citologia , Nervo Óptico/metabolismo , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Ratos , Ratos Long-Evans , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
After acute myocardial infarction, the presence of no-reflow (or microvascular obstruction: MVO) has been associated with adverse left ventricular (LV) remodeling and worse clinical outcome. This study examined the effects of mechanical ischemic postconditioning on early and late MVO size in acute ST-elevation myocardial infarction (STEMI) patients. Fifty patients undergoing primary coronary angioplasty for a first STEMI with TIMI grade flow 0-1 and no collaterals were randomized to ischemic postconditioning (PC) (n = 25) or control (n = 25) groups. Ischemic PC consisted in the application of four consecutive cycles of a 1-min balloon occlusion, each followed by a 1-min deflation at the onset of reperfusion. Early (3 min post-contrast) and late (10 min post-contrast) MVO size were assessed by contrast-enhanced cardiac-MRI within 96 h after reperfusion. PC was associated with smaller early and late MVO size (3.9 ± 4.8 in PC versus 7.8 ± 6.6% of LV in controls for early MVO, P = 0.02; and 1.8 ± 3.1 in PC versus 4.1 ± 3.9% of LV in controls for late MVO; P = 0.01). This significant reduction was persistent after adjustment for thrombus aspiration, which neither had any significant effect on infarct size, nor on early or late MVO (P = NS for all). Attenuation of MVO was associated to infarct size reduction. Mechanical postconditioning significantly reduces MVO in patients with acute STEMI treated with primary angioplasty.
Assuntos
Pós-Condicionamento Isquêmico/métodos , Infarto do Miocárdio/terapia , Angioplastia Coronária com Balão , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Masculino , Microcirculação , Pessoa de Meia-Idade , Infarto do Miocárdio/patologia , Resultado do TratamentoRESUMO
The Harlequin mutant mouse, characterized by loss of function of apoptosis-inducing factor, represents a reliable genetic model that resembles pathologies caused by human mitochondrial complex I deficiency. Therefore, we extensively characterized the retinal morphology and function of Harlequin mice during the course of neuronal cell death leading to blindness, with the aim of preventing optic atrophy. Retinas and optic nerves from these mice showed an isolated respiratory chain complex I defect correlated with retinal ganglion cell loss, optic atrophy, glial and microglial cell activation. All of these changes led to irreversible vision loss. In control mice, retinas AIF1 messenger RNA was 2.3-fold more abundant than AIF2, both messenger RNAs being sorted to the mitochondrial surface. In Harlequin mouse retinas, there was a 96% decrease of both AIF1 and AIF2 messenger RNA steady-state levels. We attained substantial and long-lasting protection of retinal ganglion cell and optic nerve integrity, the preservation of complex I function in optic nerves, as well as the prevention of glial and microglial responses after intravitreal administration of an AAV2 vector containing the full-length open reading frame and the 3' untranslated region of the AIF1 gene. Therefore, we demonstrate that gene therapy for mitochondrial diseases due to mutations in nuclear DNA can be achieved, so long as the 'therapeutic gene' permits the accurate cellular localization of the corresponding messenger RNA.
Assuntos
Fator de Indução de Apoptose/genética , Regulação para Baixo , Terapia Genética , Atrofia Óptica/terapia , Animais , Fator de Indução de Apoptose/metabolismo , Modelos Animais de Doenças , Camundongos , Atrofia Óptica/genética , Atrofia Óptica/patologia , Nervo Óptico/metabolismo , Nervo Óptico/patologia , Retina/metabolismo , Retina/patologiaRESUMO
OBJECTIVE: To determine the prevalence of, and identify associated factors with, overweight and obesity in two samples of French children. DESIGN: We conducted two cross-sectional studies among two samples of children. Weight status, eating behaviour, sedentary activity, physical activity and parents' socio-economic status (SES) were collected using questionnaires filled by doctors during school health check-ups. Overweight and obesity were defined according to the age- and sex-specific BMI cut-off points of the International Obesity Taskforce. Multivariate analysis (logistic regression) was used to identify independent factors associated with overweight including obesity and obesity alone. SETTING: Aquitaine region (south-west France). SUBJECTS: Analyses were conducted among children aged 5-7 years (n 4048) and 7-11 years (n 3619). RESULTS: Overweight prevalence was 9·5 % including 2·2 % of obesity in 5-7-year-old children and 15·6 % including 2·9 % of obesity in 7-11-year-old children. In both samples, overweight and obesity prevalence were higher in children whose parents had low or medium SES (P < 0·05). Factors associated significantly (P < 0·05) and independently with higher overweight or obesity prevalence were female gender, low or medium parental SES, never or sometimes having breakfast, never eating at the school canteen, never having a morning snack, never or sometimes having a light afternoon meal and having high sedentary activity. CONCLUSIONS: Our data confirm that low SES, absence of breakfast and high sedentary activity are associated with a higher risk of being overweight or obese, but also highlight original potential protective factors such as eating at the canteen and high meal frequency.
Assuntos
Comportamento Infantil , Comportamentos Relacionados com a Saúde , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Índice de Massa Corporal , Criança , Pré-Escolar , Estudos Transversais , Feminino , França/epidemiologia , Humanos , Modelos Logísticos , Masculino , Refeições , Análise Multivariada , Obesidade/etiologia , Sobrepeso/etiologia , Prevalência , Fatores de Risco , Instituições Acadêmicas , Comportamento Sedentário , Fatores Sexuais , Classe Social , Inquéritos e QuestionáriosRESUMO
AIM: To assess time trends in overweight and obesity prevalence among 5-6-year-old children of Bordeaux city (France) over seven school years from 2004-2005 to 2010-2011. METHODS: For each year, all 5-6-year-old children from 63 of the 69 schools of Bordeaux were included: 2005, 2100, 2010, 1952, 2040, 2017 and 2111 subjects, respectively. Weight and height were collected by school doctors, and weight status was defined according to the age- and sex-specific body mass index cut-off points of the International Obesity Task Force (IOTF) for obesity and to the French age- and gender-specific child cut-off (close to the IOTF cut-off) for overweight including obesity. RESULTS: From 2004-2005 to 2010-2011, an overall decrease was observed in overweight including obesity (from 8.9% to 5.2%, p < 0.001) and obesity prevalences (from 2.8% to 1.4%, p = 0.046). Similar results were observed in non-low socio-economic status (SES) areas (p < 0.001), whereas the prevalence did not vary significantly in low-SES areas (p > 0.05). CONCLUSION: Overweight prevalence has decreased between 2004 and 2011 in 5-6-year-old children from Bordeaux. However, the gap between low and non-low-SES areas has persisted during these years.
Assuntos
Obesidade/epidemiologia , Serviços Preventivos de Saúde/organização & administração , Classe Social , Fatores Etários , Índice de Massa Corporal , Criança , Pré-Escolar , Feminino , França , Humanos , Masculino , Obesidade/prevenção & controle , Prevalência , Fatores de Risco , Fatores de TempoRESUMO
Background: The inflammatory process underlying atrial myopathy may affect the inflammatory response activated in acute ischemic stroke (AIS). Objectives: We aimed to assess whether left atrial enlargement (LAE) as a marker of atrial myopathy is associated with a different profile of circulating inflammatory markers in AIS patients. Methods: HIBISCUS-STROKE is a cohort study including anterior circulation AIS patients treated with mechanical thrombectomy following MRI. Ten circulating inflammatory markers were measured at admission and 6, 24, and 48â h after admission. LAE was defined as a left atrial volume index (LAVi) ≥34â ml/m2. A multiple logistic regression model was performed to detect an independent association between the area under the curve (AUC) of these markers and LAE. Results: We included 143 patients. Of them, 85 (59.4%) had LAE. On univariable analysis, we found that patients with LAE had higher soluble form suppression of tumorigenicity 2 (sST2), soluble tumor necrosis factor receptor I (sTNFR1), and vascular cellular adhesion molecule-1 (VCAM-1) AUC, were older, mostly female, had a higher National Institutes of Health Stroke Scale (NIHSS) score and blood glucose level at admission, had more often hypertension, and a cardioembolic source of AIS, such as atrial fibrillation, while they were less frequently current smokers and had a lower rate of tandem occlusion than patients without LAE. On multivariable analysis, we found that among circulating inflammatory markers, only high VCAM-1 (OR: 9.13, 95% CI: 3.21-25.9) and sST2 (OR: 3.40, 95% CI: 1.68-6.86) AUC remained associated with LAE. Conclusions: High VCAM-1 and sST2 levels within the first 48â h are associated with LAE in AIS patients.
RESUMO
Background: Women are more likely to develop heart failure (HF) after myocardial infarction. However, diagnosis and reperfusion are often delayed. Objectives: To compare the prevalence of HF after primary percutaneous coronary intervention (PPCI)-treated ST segment myocardial infarction (STEMI) between sexes and to study its associations with comorbidities, infarct size, and left ventricular (LV) systolic and diastolic dysfunctions (DD). Methods: The patients with PPCI-treated anterior STEMI, from the CIRCUS study cohort, were followed up for 1 year and HF events were recorded. Evaluation of ejection fraction (LVEF) and DD were performed at baseline and at 1 year. The elevated LV filling pressure (LVFP) included Grades 2 and 3 DD. Results: Of the 791 patients from the CIRCUS study, 135 were women. At 1 year, the proportion of patients who developed HF was 21% among men and 34% among women (p = 0.001). In the subset of 407 patients with available diastolic parameters, the rate of HF was also higher in women. HF during the initial hospitalization was comparable between the sexes. However, women had a higher incidence of rehospitalization for HF within the first year after STEMI (14.1% vs. 4.1%, p = 0.005). Women were older with a higher prevalence of hypertension. The infarct size and LVEF were similar between the sexes. Elevated LVFP was observed more frequently in women than in men during the initial hospitalization and at 1 year (26% vs. 12%, p = 0.04, and 22% vs. 12%, p = 0.006, respectively). Interestingly, only initial elevated LVFP (HR 5.9, 95% CI: 2.4-14.5, p < 0.001), age, and hypertension were independently associated with rehospitalization for HF. Conclusions: After PPCI-treated anterior STEMI, despite comparable infarct size and LVEF, women presented a higher proportion of rehospitalization for HF than men. That was likely due to a greater DD associated with older age and hypertension.