RESUMO
AIM: Leigh syndrome (LS), the most common paediatric presentation of genetic mitochondrial dysfunction, is a multi-system disorder characterised by severe neurologic and metabolic abnormalities. Symmetric, bilateral, progressive necrotizing lesions in the brainstem are defining features of the disease. Patients are often symptom free in early life but typically develop symptoms by about 2 years of age. The mechanisms underlying disease onset and progression in LS remain obscure. Recent studies have shown that the immune system causally drives disease in the Ndufs4(-/-) mouse model of LS: treatment of Ndufs4(-/-) mice with the macrophage-depleting Csf1r inhibitor pexidartinib prevents disease. While the precise mechanisms leading to immune activation and immune factors involved in disease progression have not yet been determined, interferon-gamma (IFNγ) and interferon gamma-induced protein 10 (IP10) were found to be significantly elevated in Ndufs4(-/-) brainstem, implicating these factors in disease. Here, we aimed to explore the role of IFNγ and IP10 in LS. METHODS: To establish the role of IFNγ and IP10 in LS, we generated IFNγ and IP10 deficient Ndufs4(-/-)/Ifng(-/-) and Ndufs4(-/-)/IP10(-/-) double knockout animals, as well as IFNγ and IP10 heterozygous, Ndufs4(-/-)/Ifng(+/-) and Ndufs4(-/-)/IP10(+/-), animals. We monitored disease onset and progression to define the impact of heterozygous or homozygous loss of IFNγ and IP10 in LS. RESULTS: Loss of IP10 does not significantly impact the onset or progression of disease in the Ndufs4(-/-) model. IFNγ loss significantly extends survival and delays disease progression in a gene dosage-dependent manner, though the benefits are modest compared to Csf1r inhibition. CONCLUSIONS: IFNγ contributes to disease onset and progression in LS. Our findings suggest that IFNγ targeting therapies may provide some benefits in genetic mitochondrial disease, but targeting IFNγ alone would likely yield only modest benefits in LS.
Assuntos
Progressão da Doença , Complexo I de Transporte de Elétrons , Interferon gama , Doença de Leigh , Animais , Camundongos , Tronco Encefálico/patologia , Tronco Encefálico/metabolismo , Modelos Animais de Doenças , Complexo I de Transporte de Elétrons/genética , Complexo I de Transporte de Elétrons/deficiência , Interferon gama/metabolismo , Doença de Leigh/patologia , Doença de Leigh/genética , Camundongos Endogâmicos C57BL , Camundongos KnockoutRESUMO
BACKGROUND: Mutations in several genes of Caenorhabditis elegans confer altered sensitivities to volatile anesthetics. A mutation in one gene, gas-1(fc21), causes animals to be immobilized at lower concentrations of all volatile anesthetics than in the wild type, and it does not depend on mutations in other genes to control anesthetic sensitivity. gas-1 confers different sensitivities to stereoisomers of isoflurane, and thus may be a direct target for volatile anesthetics. The authors have cloned and characterized the gas gene and the mutant allele fc21. METHODS: Genetic techniques for nematodes were as previously described. Polymerase chain reaction, sequencing, and other molecular biology techniques were performed by standard methods. Mutant rescue was done by injecting DNA fragments into the gonad of mutant animals and scoring the offspring for loss of the mutant phenotype. RESULTS: The gas-1 gene was cloned and identified. The protein GAS-1 is a homologue of the 49-kd (IP) subunit of the mitochondrial NADH-ubiquinone-oxidoreductase (complex I of the respiratory chain). gas-1(fc21) is a missense mutation replacing a strictly conserved arginine with lysine. CONCLUSIONS: The function of the 49-kd (IP) subunit of complex I is unknown. The finding that mutations in complex I increase sensitivity of C. elegans to volatile anesthetics may implicate this physiologic process in the determination of anesthetic sensitivity. The hypersensitivity of animals with a mutation in the gas-1 gene may be caused by a direct anesthetic effect on a mitochondrial protein or secondary effects at other sites caused by mitochondrial dysfunction.
Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/efeitos dos fármacos , Proteínas de Caenorhabditis elegans/genética , Mutação , Anestésicos Inalatórios , Complexo I de Transporte de Elétrons/genética , Complexo I de Transporte de Elétrons/metabolismo , Sequência de Aminoácidos , Isoflurano/farmacologiaRESUMO
BACKGROUND: Volatile anesthetics induce hyperpolarizing potassium currents in spinal cord neurons that may contribute to their mechanism of action. They are induced at lower concentrations of isoflurane in noncholinergic neurons from mice carrying a loss-of-function mutation of the Ndufs4 gene, required for mitochondrial complex I function. The yeast NADH dehydrogenase enzyme, NDi1, can restore mitochondrial function in the absence of normal complex I activity, and gain-of-function Ndi1 transgenic mice are resistant to volatile anesthetics. The authors tested whether NDi1 would reduce the hyperpolarization caused by isoflurane in neurons from Ndufs4 and wild-type mice. Since volatile anesthetic behavioral hypersensitivity in Ndufs4 is transduced uniquely by glutamatergic neurons, it was also tested whether these currents were also unique to glutamatergic neurons in the Ndufs4 spinal cord. METHODS: Spinal cord neurons from wild-type, NDi1, and Ndufs4 mice were patch clamped to characterize isoflurane sensitive currents. Neuron types were marked using fluorescent markers for cholinergic, glutamatergic, and γ-aminobutyric acid-mediated (GABAergic) neurons. Norfluoxetine was used to identify potassium channel type. Neuron type-specific Ndufs4 knockout animals were generated using type-specific Cre-recombinase with floxed Ndufs4. RESULTS: Resting membrane potentials (RMPs) of neurons from NDi1;Ndufs4, unlike those from Ndufs4, were not hyperpolarized by 0.6% isoflurane (Ndufs4, ΔRMP -8.2 mV [-10 to -6.6]; P = 1.3e-07; Ndi1;Ndufs4, ΔRMP -2.1 mV [-7.6 to +1.4]; P = 1). Neurons from NDi1 animals in a wild-type background were not hyperpolarized by 1.8% isoflurane (wild-type, ΔRMP, -5.2 mV [-7.3 to -3.2]; P = 0.00057; Ndi1, ΔRMP, 0.6 mV [-1.7 to 3.2]; P = 0.68). In spinal cord slices from global Ndufs4 animals, holding currents (HC) were induced by 0.6% isoflurane in both GABAergic (ΔHC, 81.3 pA [61.7 to 101.4]; P = 2.6e-05) and glutamatergic (ΔHC, 101.2 pA [63.0 to 146.2]; P = 0.0076) neurons. In neuron type-specific Ndufs4 knockouts, HCs were increased in cholinergic (ΔHC, 119.5 pA [82.3 to 156.7]; P = 0.00019) and trended toward increase in glutamatergic (ΔHC, 85.5 pA [49 to 126.9]; P = 0.064) neurons but not in GABAergic neurons. CONCLUSIONS: Bypassing complex I by overexpression of NDi1 eliminates increases in potassium currents induced by isoflurane in the spinal cord. The isoflurane-induced potassium currents in glutamatergic neurons represent a potential downstream mechanism of complex I inhibition in determining minimum alveolar concentration.
Assuntos
Anestésicos Inalatórios , Isoflurano , Camundongos , Animais , Isoflurano/farmacologia , Anestésicos Inalatórios/farmacologia , Canais de Potássio , Medula Espinal , Camundongos Transgênicos , Interneurônios , Complexo I de Transporte de Elétrons/genética , ColinérgicosRESUMO
BACKGROUND: Dads and Daughters Exercising and Empowered (DADEE) is a program targeting fathers/father-figures to improve their daughters' physical activity and well-being. Previous randomised controlled efficacy and effectiveness trials of DADEE demonstrated meaningful improvements in a range of holistic outcomes for both fathers and daughters in the short-term. This study aims to assess the long-term impact (12-months) of the program when delivered in the community by trained facilitators. METHODS: Fathers/father-figures and their primary school-aged daughters were recruited from Newcastle, Australia into a single-arm, non-randomised, pre-post study with assessments at baseline, 10-weeks (post-intervention) and 12-months. The 9-session program included weekly 90-min educational and practical sessions, plus home-based tasks. The primary outcome was fathers' and daughters' days per week meeting national physical activity recommendations (≥ 30 min/day of MVPA for fathers, ≥ 60 min/day MVPA for daughters). Secondary outcomes included physical activity, screen time, self-esteem, father-daughter relationship, social-emotional well-being, parenting measures, and process outcomes (including recruitment, attendance, retention and program acceptability). RESULTS: Twelve programs were delivered with 257 fathers (40.0 ± 9.2 years) and 285 daughters (7.7 ± 1.9 years). Mixed effects regression models revealed significant intervention effects for the primary outcome, with fathers increasing the days/week meeting physical activity recommendations by 27% at 10-weeks (p < 0.001) and by 19% at 12-months (p < 0.001) compared with baseline. Likewise, for daughters there was a significant increase by 25% at 10-weeks (p < 0.001) and by 14% at 12-months (p = 0.02) when compared to baseline. After conducting a sensitivity analysis with participants unaffected by COVID-19 lockdowns (n = 175 fathers, n = 192 daughters), the primary outcome results strengthened at both time-points for fathers and at 12-months for daughters. Additionally, the sensitivity analysis revealed significant intervention effects at post-program and 12-months for all secondary outcomes in both fathers and daughters. Furthermore, the process outcomes for recruitment capability, attendance, retention and satisfaction levels were high. CONCLUSIONS: Findings provide support for a sustained effect of the DADEE program while delivered in a community setting by trained facilitators. Further investigation is required to identify optimised implementation processes and contextual factors to deliver the program at scale. TRIAL REGISTRATION: ACTRN12617001450303 . Date registered: 12/10/2017.
Assuntos
Exercício Físico , Relações Pai-Filho , Pai , Promoção da Saúde , Humanos , Feminino , Masculino , Criança , Promoção da Saúde/métodos , Adulto , Austrália , Avaliação de Programas e Projetos de Saúde , Poder Familiar/psicologia , Núcleo Familiar , COVID-19/prevenção & controle , AutoimagemRESUMO
OBJECTIVES: To assess the inclusion of Aboriginal and Torres Strait Islander parents in trials of parenting programs in Australia; the involvement of Indigenous fathers in such studies; and whether parenting programs are designed to be culturally appropriate for Aboriginal and Torres Strait Islander people. STUDY DESIGN: Scoping review of peer-reviewed journal publications that report quantitative outcomes for Australian randomised control trials of parenting programs in which the participants were parents or caregivers of children under 18 years of age, and with at least one outcome related to children's health, health behaviour, or wellbeing. DATA SOURCES: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Scopus databases. DATA SYNTHESIS: Of 109 eligible publications, nine reported how many participants were Aboriginal or Torres Strait Islander people; three specified whether they were Aboriginal, Torres Strait Islander, or both. Two publications described specific interventions for Aboriginal and Torres Strait Islander children; both reported consultation with Indigenous people regarding program design. Of the 15 559 participating parents in all included publications, 93 were identified as Aboriginal or Torres Strait Islander people. No publications noted as study limitations the absence of consultation with Indigenous people or the low participation rate of Aboriginal and Torres Strait Islander families. CONCLUSIONS: The specific needs and interests of Aboriginal and Torres Strait Islander families have not generally been considered in Australian trials of parenting programs that aim to improve the mental and physical health of children. Further, Indigenous people are rarely involved in the planning and implementation of the interventions, few of which are designed to be culturally appropriate for Indigenous people. If parenting research in Australia is to support Aboriginal and Torres Strait Islander families, it must include consultation with local communities, adapt interventions and research methods to the needs of the participating parents and their communities, and improve the recruitment and retention of Aboriginal and Torres Strait Islander participants.
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Povos Aborígenes Australianos e Ilhéus do Estreito de Torres , Serviços de Saúde do Indígena , Criança , Humanos , Adolescente , Poder Familiar , Saúde da Criança , Austrália , Pais , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
PURPOSE: To investigate gaze and behavioural metrics at different viewing distances with multifocal contact lenses (MFCLs), single vision contact lenses (SVCLs) and progressive addition lenses (PALs). METHODS: Fifteen presbyopic contact lens wearers participated over five separate study visits. At each visit, participants were randomly assigned to wear one of five refractive corrections: habitual PAL spectacles, delefilcon A (Alcon Inc.) MFCLs and three separate pairs of delefilcon A single vision lenses worn as distance, intermediate and near corrections. Participants wore a Pupil Core headset to record eye and head movements while performing three visual tasks: reading, visual search and scene observation. Data were investigated using linear regression and post-hoc testing. Parameters of interest included gaze (fixation duration, head movement) and behavioural (reading speed, reading accuracy, visual search time) metrics. RESULTS: Reading speed in SVCLs was significantly faster than in MFCLs and PAL spectacles (F = 16.3, p < 0.0001). Refractive correction worn did not influence visual search times (F = 0.16, p = 0.85). Fixation duration was significantly affected by the type of visual task (F = 60.2, p < 0.001), and an interaction effect was observed between viewing distance and refractive correction (F = 4.3, p = 0.002). There was significantly more horizontal and vertical head movement (F = 3.2, p = 0.01 and F = 3.3, p = 0.01, respectively) during visual search tasks when wearing PAL spectacles compared to SVCLs or MFCLs. CONCLUSION: This work showed that the type of refractive correction affects behavioural metrics such as reading speed and gaze behaviour by affecting horizontal and vertical head movements. The findings of this study suggest that under certain conditions, wearers of MFCLs make fewer head movements compared to PAL spectacles. Gaze behaviour metrics offer a new approach to compare and understand contact lens and spectacle performance, with potential applications including peripheral optical designs for myopia management.
Assuntos
Lentes de Contato , Óculos , Fixação Ocular , Presbiopia , Leitura , Refração Ocular , Acuidade Visual , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Movimentos Oculares/fisiologia , Fixação Ocular/fisiologia , Movimentos da Cabeça/fisiologia , Presbiopia/fisiopatologia , Presbiopia/terapia , Refração Ocular/fisiologia , Acuidade Visual/fisiologia , Estudos Cross-Over , Estudos ProspectivosRESUMO
PURPOSE: To investigate whether there is a measurable change in meibomian gland morphological characteristics over the course of a day (12 h) and over a month. METHODS: The study enrolled 15 participants who attended a total of 11 study visits spanning a 5-week period. To assess diurnal changes in meibomian glands, seven visits were conducted on a single day, each 2 h apart. For monthly assessment, participants attended an additional visit at the same time of the day every week for three consecutive weeks. Meibography using the LipiView® II system was performed at each visit, and meibomian gland morphological parameters were calculated using custom semi-automated software. Specifically, six central glands were analysed for gland length ratio, gland width, gland area, gland intensity and gland tortuosity. RESULTS: The average meibomian gland morphological metrics did not exhibit significant changes during the course of a day or over a month. Nonetheless, certain individual gland metrics demonstrated notable variation over time, both diurnally and monthly. Specifically, meibomian gland length ratio, area, width and tortuosity exhibited significant changes both diurnally and monthly when assessed on a gland-by-gland basis. CONCLUSIONS: Meibomian glands demonstrated measurable structural change over short periods of time (hours and days). These results have implications for innovation in gland imaging and for developing precision monitoring of gland structure to assess meibomian gland health more accurately.
Assuntos
Glândulas Tarsais , Humanos , Glândulas Tarsais/diagnóstico por imagem , Glândulas Tarsais/anatomia & histologia , Projetos Piloto , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Idoso , Disfunção da Glândula Tarsal/diagnóstico , Disfunção da Glândula Tarsal/diagnóstico por imagem , Lágrimas/fisiologia , Ritmo Circadiano/fisiologia , Fatores de TempoRESUMO
PURPOSE: To investigate differences in key clinical parameters between asymptomatic and highly symptomatic soft contact lens (CL) wearers after 14 h of wear. METHODS: In this pilot investigation, Phase 1 identified asymptomatic (CLDEQ-8 score ≤ 7) and highly symptomatic (CLDEQ-8 score ≥ 20) subjects after fitting with nelfilcon A CLs. Phase 2 investigated the following over a single nelfilcon A CL-wearing day (14 ± 2 h): blinking characteristics, tear meniscus height (TMH), non-invasive tear break-up time (NIBUT), tear film osmolarity and eyelid margin staining. Parameters for the two groups were compared using linear mixed models and post-hoc testing. The relationship between comfort scores and the clinical parameters was also investigated. RESULTS: Overall, 161 and 42 subjects were enrolled into Phase 1 and 2, respectively. Twenty-five asymptomatic and 17 symptomatic subjects completed Phase 2. Lower eyelid TMH was decreased after 14 h in symptomatic compared with asymptomatic subjects (least square mean [LSM] difference -0.04 mm, 95% CI: -0.07, -0.01). Osmolarity was lower in symptomatic than in asymptomatic subjects at fitting (LSM difference -9.89, 95% CI: -18.91, -0.86). Upper eyelid margin staining was greater after 14 h in symptomatic than in asymptomatic subjects (LSM difference 0.53, 95% CI: 0.01, 1.05) and greater after 14 h than baseline in the symptomatic group (LSM difference 0.61, 95% CI: 0.16, 1.07). There was a significant relationship between comfort and upper eyelid margin staining (r = -0.40, 95% CI: -0.63, -0.11) and blink rate (r = -0.31, 95% CI: -0.57, -0.003). CONCLUSION: The potential parameters most effective in differentiating asymptomatic from symptomatic wearers were upper eyelid margin staining and lower TMH. The parameter with the strongest relationship to comfort was upper eyelid margin staining, where higher comfort scores were associated with lower levels of staining.
Assuntos
Piscadela , Lentes de Contato Hidrofílicas , Lágrimas , Humanos , Lentes de Contato Hidrofílicas/efeitos adversos , Masculino , Feminino , Adulto , Lágrimas/metabolismo , Lágrimas/fisiologia , Projetos Piloto , Piscadela/fisiologia , Adulto Jovem , Concentração Osmolar , Síndromes do Olho Seco/diagnóstico , Síndromes do Olho Seco/etiologia , Síndromes do Olho Seco/fisiopatologia , PálpebrasRESUMO
BACKGROUND: Genetic mitochondrial diseases impact over 1 in 4000 individuals, most often presenting in infancy or early childhood. Seizures are major clinical sequelae in some mitochondrial diseases including Leigh syndrome, the most common pediatric presentation of mitochondrial disease. Dietary ketosis has been used to manage seizures in mitochondrial disease patients. Mitochondrial disease patients often require surgical interventions, leading to anesthetic exposures. Anesthetics have been shown to be toxic in the setting of mitochondrial disease, but the impact of a ketogenic diet on anesthetic toxicities in this setting has not been studied. AIMS: Our aim in this study was to determine whether dietary ketosis impacts volatile anesthetic toxicities in the setting of genetic mitochondrial disease. METHODS: The impact of dietary ketosis on toxicities of volatile anesthetic exposure in mitochondrial disease was studied by exposing young Ndufs4(-/-) mice fed ketogenic or control diet to isoflurane anesthesia. Blood metabolites were measured before and at the end of exposures, and survival and weight were monitored. RESULTS: Compared to a regular diet, the ketogenic diet exacerbated hyperlactatemia resulting from isoflurane exposure (control vs. ketogenic diet in anesthesia mean difference 1.96 mM, Tukey's multiple comparison adjusted p = .0271) and was associated with a significant increase in mortality during and immediately after exposures (27% vs. 87.5% mortality in the control and ketogenic diet groups, respectively, during the exposure period, Fisher's exact test p = .0121). Our data indicate that dietary ketosis and volatile anesthesia interact negatively in the setting of mitochondrial disease. CONCLUSIONS: Our findings suggest that extra caution should be taken in the anesthetic management of mitochondrial disease patients in dietary ketosis.
Assuntos
Anestesia , Anestésicos , Isoflurano , Cetose , Doença de Leigh , Doenças Mitocondriais , Humanos , Criança , Pré-Escolar , Camundongos , Animais , Doença de Leigh/genética , Dieta , Cetose/metabolismo , Convulsões , Complexo I de Transporte de Elétrons/metabolismoRESUMO
'Healthy Youngsters, Healthy Dads' (HYHD) targets fathers to improve the health of their preschool-aged children. In a previous randomized trial, fathers and children experienced meaningful improvements in physical activity and eating behaviours. The next phase is to test the replicability and adaptability of HYHD when delivered in the community by trained facilitators. Fathers/father-figures and children aged 3-5 years were recruited from Newcastle, Australia into a 9-week, non-randomized trial with assessments at baseline, 10 weeks, and 12 months. The primary outcome was achievement of pre-registered targets for recruitment (≥â 96 dyads), attendance (≥â 70%), compliance (completingâ ≥â 70% of home-based tasks), fidelity (≥â 80% of content delivered as intended) and program satisfaction (≥â 4/5). Secondary outcomes included physical activity, nutrition, screen time and parenting measures. Process targets were surpassed for recruitment (140 fathers, 141 children), attendance (79% for fathers-only workshops, 81% for father-child sessions), compliance (80% of home-tasks completed), fidelity (99% for education,â ≥â 97% for practical) and program satisfaction (4.8/5). Mixed effects regression models revealed significant effects in fathers for moderate-to-vigorous physical activity, co-physical activity, dietary intake and parenting practises, which were maintained at 12 months. Significant effects were also established for screen time at 10 weeks only. For children, significant effects were observed for screen time and dietary intake at 10 weeks, while effects on energy-dense, nutrient-poor foods and healthy, nutrient-dense core food intake were maintained at 12 months. Findings demonstrate the replicability and adaptability of HYHD when delivered in the community by local trained facilitators. Further investigation into how to optimally scale-up HYHD is warranted.
Assuntos
Exercício Físico , Pai , Promoção da Saúde , Humanos , Masculino , Pré-Escolar , Promoção da Saúde/métodos , Feminino , Austrália , Pai/psicologia , Poder Familiar/psicologia , Adulto , Comportamento Alimentar/psicologia , DietaRESUMO
This study aimed to examine the preliminary efficacy and feasibility of implementing a tailored version of the MASTER coach education programme in Chinese primary schools to support physical education (PE) teachers' basketball lesson design and delivery. A total of 20 primary schools in Beijing, China were recruited, with one PE teacher and their class (N = 715 students aged 10-13 yrs) from each school included in the study and randomly allocated to the MASTER intervention (n = 10) or control group (n = 10). Compared to the control group, a significant difference was observed in the MASTER group for the proportion of playing-form activities delivered during PE (27.65, 95% CI [20.27, 35.03]) and for teachers' perceptions of confidence (23.92, 95% CI [15.87, 31.92]) and competence (24.12, 95% CI [10.28, 24.71]) to teach. Significant differences between groups were observed for students' perceived athletic competence (3.56%; 95% CI [3.15, 3.96]), enjoyment (11.83%; 95% CI [10.98, 12.69]), well-being (8.51%; 95% CI [7.02, 10.00]), intrinsic motivation (+0.74%; 95% CI [0.30, 1.17]), introjected motivation (-2.24%; 95% CI [-2.77, -1.70]), and external motivation (-0.49%; 95% CI [-0.90, -0.08]). The MASTER programme was effective in improving teaching practices in Chinese primary schools, and in facilitating improvements in teacher and student outcomes.
Assuntos
Basquetebol , Humanos , Educação Física e Treinamento , Projetos Piloto , Instituições Acadêmicas , Estudantes , Motivação , Professores Escolares , EnsinoRESUMO
Cytosolic mRNA translation is subject to global and mRNA-specific controls. Phosphorylation of the translation initiation factor eIF2α anchors a reversible regulatory switch that represses cytosolic translation globally. The stress-responsive GCN2 kinase is the only known kinase for eIF2α serine 56 in Arabidopsis (Arabidopsis thaliana). Here, we show that conditions that generate reactive oxygen species (ROS) in the chloroplast, including dark-light transitions, high light, and the herbicide methyl viologen, rapidly activated GCN2 kinase, whereas mitochondrial and endoplasmic reticulum stress did not. GCN2 activation was light dependent and mitigated by photosynthesis inhibitors and ROS quenchers. Accordingly, the seedling growth of multiple Arabidopsis gcn2 mutants was retarded under excess light conditions, implicating the GCN2-eIF2α pathway in responses to light and associated ROS. Once activated, GCN2 kinase preferentially suppressed the ribosome loading of mRNAs for functions such as mitochondrial ATP synthesis, the chloroplast thylakoids, vesicle trafficking, and translation. The gcn2 mutant overaccumulated transcripts functionally related to abiotic stress, including oxidative stress, as well as innate immune responses. Accordingly, gcn2 displayed defects in immune priming by the fungal elicitor, chitin. Therefore, we provide evidence that reactive oxygen species produced by the photosynthetic apparatus help activate the highly conserved GCN2 kinase, leading to eIF2α phosphorylation and thus affecting the status of the cytosolic protein synthesis apparatus.
Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Arabidopsis/efeitos da radiação , Cloroplastos/metabolismo , Cloroplastos/efeitos da radiação , Luz , Biossíntese de Proteínas/efeitos da radiação , Proteínas Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Quitina/metabolismo , Fator de Iniciação 2 em Eucariotos/metabolismo , Ontologia Genética , Herbicidas/toxicidade , Peróxido de Hidrogênio/farmacologia , Mutação/genética , Fosforilação/efeitos da radiação , Fotossíntese/efeitos dos fármacos , Ribossomos/efeitos dos fármacos , Ribossomos/metabolismo , Ribossomos/efeitos da radiação , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/efeitos da radiação , Transcriptoma/genéticaRESUMO
BACKGROUND: A variety of molecular targets for volatile anesthetics have been suggested, including the anesthetic-sensitive potassium leak channel, TREK-1. Knockout of TREK-1 is reported to render mice resistant to volatile anesthetics, making TREK-1 channels compelling targets for anesthetic action. Spinal cord slices from mice, either wild type or an anesthetic- hypersensitive mutant, Ndufs4, display an isoflurane-induced outward potassium leak that correlates with their minimum alveolar concentrations and is blocked by norfluoxetine. The hypothesis was that TREK-1 channels conveyed this current and contribute to the anesthetic hypersensitivity of Ndufs4. The results led to evaluation of a second TREK channel, TREK-2, in control of anesthetic sensitivity. METHODS: The anesthetic sensitivities of mice carrying knockout alleles of Trek-1 and Trek-2, the double knockout Trek-1;Trek-2, and Ndufs4;Trek-1 were measured. Neurons from spinal cord slices from each mutant were patch clamped to characterize isoflurane-sensitive currents. Norfluoxetine was used to identify TREK-dependent currents. RESULTS: The mean values for minimum alveolar concentrations (± SD) between wild type and two Trek-1 knockout alleles in mice (P values, Trek-1 compared to wild type) were compared. For wild type, minimum alveolar concentration of halothane was 1.30% (0.10), and minimum alveolar concentration of isoflurane was 1.40% (0.11); for Trek-1tm1Lex, minimum alveolar concentration of halothane was 1.27% (0.11; P = 0.387), and minimum alveolar concentration of isoflurane was 1.38% (0.09; P = 0.268); and for Trek-1tm1Lzd, minimum alveolar concentration of halothane was 1.27% (0.11; P = 0.482), and minimum alveolar concentration of isoflurane was 1.41% (0.12; P = 0.188). Neither allele was resistant for loss of righting reflex. The EC50 values of Ndufs4;Trek-1tm1Lex did not differ from Ndufs4 (for Ndufs4, EC50 of halothane, 0.65% [0.05]; EC50 of isoflurane, 0.63% [0.05]; and for Ndufs4;Trek-1tm1Lex, EC50 of halothane, 0.58% [0.07; P = 0.004]; and EC50 of isoflurane, 0.61% [0.06; P = 0.442]). Loss of TREK-2 did not alter anesthetic sensitivity in a wild-type or Trek-1 genetic background. Loss of TREK-1, TREK-2, or both did not alter the isoflurane-induced currents in wild-type cells but did cause them to be norfluoxetine insensitive. CONCLUSIONS: Loss of TREK channels did not alter anesthetic sensitivity in mice, nor did it eliminate isoflurane-induced transmembrane currents. However, the isoflurane-induced currents are norfluoxetine-resistant in Trek mutants, indicating that other channels may function in this role when TREK channels are deleted.
Assuntos
Anestésicos Inalatórios , Isoflurano , Canais de Potássio de Domínios Poros em Tandem , Animais , Camundongos , Isoflurano/farmacologia , Halotano/farmacologia , Anestésicos Inalatórios/farmacologia , Camundongos Knockout , Canais de Potássio de Domínios Poros em Tandem/genética , Complexo I de Transporte de Elétrons/genéticaRESUMO
BACKGROUND: Volatile anaesthetics are widely used in human medicine. Although generally safe, hypersensitivity and toxicity can occur in rare cases, such as in certain genetic disorders. Anaesthesia hypersensitivity is well-documented in a subset of mitochondrial diseases, but whether volatile anaesthetics are toxic in this setting has not been explored. METHODS: We exposed Ndufs4(-/-) mice, a model of Leigh syndrome, to isoflurane (0.2-0.6%), oxygen 100%, or air. Cardiorespiratory function, weight, blood metabolites, and survival were assessed. We exposed post-symptom onset and pre-symptom onset animals and animals treated with the macrophage depleting drug PLX3397/pexidartinib to define the role of overt neuroinflammation in volatile anaesthetic toxicities. RESULTS: Isoflurane induced hyperlactataemia, weight loss, and mortality in a concentration- and duration-dependent manner from 0.2% to 0.6% compared with carrier gas (O2 100%) or mock (air) exposures (lifespan after 30-min exposures ∗P<0.05 for isoflurane 0.4% vs air or vs O2, ∗∗P<0.005 for isoflurane 0.6% vs air or O2; 60-min exposures ∗∗P<0.005 for isoflurane 0.2% vs air, ∗P<0.05 for isoflurane 0.2% vs O2). Isoflurane toxicity was significantly reduced in Ndufs4(-/-) exposed before CNS disease onset, and the macrophage depleting drug pexidartinib attenuated sequelae of isoflurane toxicity (survival ∗∗∗P=0.0008 isoflurane 0.4% vs pexidartinib plus isoflurane 0.4%). Finally, the laboratory animal standard of care of 100% O2 as a carrier gas contributed significantly to weight loss and reduced survival, but not to metabolic changes, and increased acute mortality. CONCLUSIONS: Isoflurane is toxic in the Ndufs4(-/-) model of Leigh syndrome. Toxic effects are dependent on the status of underlying neurologic disease, largely prevented by the CSF1R inhibitor pexidartinib, and influenced by oxygen concentration in the carrier gas.
Assuntos
Anestésicos Inalatórios , Isoflurano , Doença de Leigh , Humanos , Animais , Camundongos , Isoflurano/toxicidade , Anestésicos Inalatórios/toxicidade , Doença de Leigh/genética , Oxigênio , Redução de Peso , Complexo I de Transporte de ElétronsRESUMO
PURPOSE: Our study explored the mediating effect of sleep-related variables on older adolescents' mental health in the context of a school-based physical activity intervention. METHODS: We evaluated the Burn 2 Learn (B2L) intervention using a cluster randomized controlled trial, which included two cohorts. Participants for this sub-study were from the second cohort, which included 292 older adolescents (16.0 ± 0.5 years) from 10 secondary schools in New South Wales, Australia. Teachers at intervention schools delivered two high-intensity activity breaks (approximately 10 mins) per week to students during academic lessons. Participants completed measures of mental health (i.e., perceived stress and internalizing problems) and hypothesized mediators (i.e., sleep duration, sleep latency, awakenings, and daytime sleepiness) at baseline (February-April 2019) and post-intervention (August-September 2019). Single mediation analyses were conducted to explore the potential mediating effects of sleep variables on mental health outcomes using a product-of-coefficient test. RESULTS: We observed a small statistically significant effect for perceived stress (ß = -0.11, SE = 0.034, p = 0.002), but not for internalizing problems (ß = 0.02, SE = 0.051, p = 0.760). There were no significant intervention effects for sleep-related variables. Several sleep-related variables were associated with mental health outcomes but no mediated effects were found. CONCLUSION: The B2L intervention had a small beneficial effect on perceived stress, however our mediation analyses suggest this was not explained by changes in sleep-related variables. Markers of sleep were associated with mental health constructs, highlighting the importance of sleep for good psychological health. However, in the context of a physical activity intervention, effects on mental health may be driven by other behavioral, neurobiological, or psychosocial mechanisms.
Assuntos
Exercício Físico , Saúde Mental , Humanos , Adolescente , Sono , Aprendizagem , AustráliaRESUMO
BACKGROUND: Fathers are important in establishing healthy behaviors in their children, but are rarely engaged in lifestyle programs. Focusing on physical activity (PA) of both fathers and their children by engaging them together in PA (i.e. "co-PA") is therefore a promising novel strategy for interventions. The study aim was to investigate the effect of the 'Run Daddy Run' on co-PA and PA of fathers and their children, and secondary outcomes such as weight status and sedentary behaviour (SB). METHODS: This study is a non-randomized controlled trial (nRCT), including 98 fathers and one of their 6 to 8 years old children (intervention = 35, control = 63). The intervention was implemented over a 14-week period, and consisted of six (inter)active father-child sessions and an online component. Due to COVID-19, only 2/6 sessions could be implemented as planned, the remaining sessions were delivered online. In November 2019-January 2020 pre-test measurements took place, and post-test measurements in June 2020. Additional follow-up test was conducted in November 2020. PA (i.e. LPA, MPA, VPA and volume) of fathers and children were objectively measured using accelerometry, co-PA and the secondary outcomes were questioned using an online questionnaire. RESULTS: Significant intervention effects were found for co-PA (+ 24 min./day in the intervention compared to the control group, p = 0.002), and MPA of the father (+ 17 min./day, p = 0.035). For children, a significant increase in LPA (+ 35 min./day, p < 0.001) was found. However, an inverse intervention effect was found for their MPA and VPA (-15 min./day, p = 0.005 and - 4 min./day, p = 0.002, respectively). Also decreases in fathers' and children's SB were found (-39 min./day, p = 0.022 and - 40 min./day, p = 0.003, respectively), but no changes in weight status, the father-child relationship, and the PA-family health climate (all p > 0.05). CONCLUSION: The Run Daddy Run intervention was able to improve co-PA, MPA of fathers and LPA of children, and decreasing their SB. Inverse intervention effects were however found for MPA and VPA of children. These results are unique given their magnitude and clinical relevance. Targeting fathers together with their children might be a novel and potential intervention strategy to improve overall physical activity levels, however, further efforts should however be made to target children's MPA and VPA. Last, replicating these findings in a randomized controlled trial (RCT) is recommended for future research. TRIAL REGISTRATION NUMBER: This study is registered as a clinical trial (clinicaltrials.gov, ID number: NCT04590755, date: 19/10/2020).
Assuntos
COVID-19 , Humanos , Criança , Masculino , COVID-19/prevenção & controle , Exercício Físico , Estilo de Vida , Comportamentos Relacionados com a Saúde , Acelerometria , PaiRESUMO
BACKGROUND: Depression and obesity are major health concerns and commonly co-exist, but men rarely seek help for these conditions. SHED-IT: Recharge was a gender-tailored eHealth program for men that generated clinically meaningful improvements in weight and depressive symptoms. PURPOSE: To evaluate behavioral and psychological outcomes from the SHED-IT: Recharge intervention designed for overweight/obese men with low mood. METHODS: Overall, 125 men (18-70 years) with a BMI between 25 and 42 kg/m2 and depressive symptoms (PHQ-9 ≥ 5) were randomly allocated to SHED-IT: Recharge (n = 62) or wait-list control (n = 63) groups. The self-directed program targeted key health behaviors combined with online mental fitness modules based on cognitive behavioral therapy. Behavioral (e.g., physical activity) and psychological outcomes (e.g., cognitive flexibility) were assessed with validated measures at baseline, 3 months (post-test) and 6 months (follow-up). Intention-to-treat linear mixed models examined treatment effects, which were adjusted for covariates, and effect size estimated (Cohen's d). RESULTS: At post-test, intervention men achieved small-to-medium improvements in several health behavior outcomes including moderate-to-vigorous physical activity, light physical activity, sedentary behavior, sleep, energy intake, portion size, and risky alcohol consumption (range, d = 0.3-0.5), when compared with the control group. Intervention effects were also observed for perceived physical self-worth, perceived physical strength, cognitive flexibility, and behavioral activation (range, d = 0.3-0.8). No effects were found for fruit and vegetable intake, or mindful attention. Most effects were maintained at follow-up. CONCLUSIONS: This gender-tailored, eHealth program with integrated mental fitness support elicited meaningful improvements in health behaviors and psychological outcomes for men with low mood. Trial Registration: Australian New Zealand Clinical Trials Registry (ACTRN12619001209189).
Assuntos
Programas de Redução de Peso , Austrália , Cognição , Humanos , Masculino , Obesidade/psicologia , Obesidade/terapia , Sobrepeso/terapia , Redução de PesoRESUMO
BACKGROUND: The 'Dads And Daughters Exercising and Empowered' (DADEE) program significantly improved physical activity levels of fathers and their daughters in an efficacy trial. However, the effectiveness of interventions when delivered in real-world settings needs to be established. PURPOSE: To evaluate the effectiveness of the DADEE intervention when delivered in community settings by trained facilitators. METHODS: We conducted a two-arm RCT, (baseline and 3-months post-intervention assessments), in Newcastle, Australia. In 2016, 155 fathers (27-60 years) and 189 primary-school-aged daughters (4-12 years) (n = 344) were randomly allocated to the intervention (78 fathers, 95 daughters) or waitlist-control (77 fathers, 94 daughters) groups. Trained facilitators delivered the 9-week DADEE program (weekly sessions plus home-based tasks). Primary outcomes were fathers' and daughters' physical activity (steps/day). Secondary outcomes included screen-time, weight status, daughters' fundamental movement skill (FMS) proficiency, perceived sports competence, and fathers' parenting practices. Effects were assessed using linear mixed models. RESULTS: Primary outcome follow-up data were collected from 88% of fathers and 89% of daughters. Significant group-by-time differences in mean daily steps were found for fathers' (adjusted difference = +1,638; 95% CI: 833, 2,443, d = 0.7) and daughters' (adjusted difference = +1,023 steps/day; 95% CI: 259, 1,787; d = 0.4) physical activity. Significant effects were observed for daughters' screen-time, FMS, and some parenting practices. No significant effects were identified for weight status, or fathers'screen-time or self-reported MVPA. Program attendance, satisfaction and fidelity were very high. CONCLUSION: This study established the effectiveness of the DADEE intervention when delivered in community settings by trained facilitators. Importantly, the findings were comparable to those of the efficacy RCT delivered by the research team. To maximize public health benefits, a larger-scale dissemination of the program appears warranted.Trial Registration Australian New Zealand Clinical Trial Registry: ACTRN12616001270404 Human Research Ethics Committee: H-2014-0330.
Assuntos
Exercício Físico , Núcleo Familiar , Austrália , Criança , Pai , Humanos , Masculino , Tempo de TelaRESUMO
BACKGROUND: If anaesthetics cause permanent cognitive deficits in some children, the implications are enormous, but the molecular causes of anaesthetic-induced neurotoxicity, and consequently possible therapies, are still debated. Anaesthetic exposure early in development can be neurotoxic in the invertebrate Caenorhabditis elegans causing endoplasmic reticulum (ER) stress and defects in chemotaxis during adulthood. We screened this model organism for compounds that alleviated neurotoxicity, and then tested these candidates for efficacy in mice. METHODS: We screened compounds for alleviation of ER stress induction by isoflurane in C. elegans assayed by induction of a green fluorescent protein (GFP) reporter. Drugs that inhibited ER stress were screened for reduction of the anaesthetic-induced chemotaxis defect. Compounds that alleviated both aspects of neurotoxicity were then blindly tested for the ability to inhibit induction of caspase-3 by isoflurane in P7 mice. RESULTS: Isoflurane increased ER stress indicated by increased GFP reporter fluorescence (240% increase, P<0.001). Nine compounds reduced induction of ER stress by isoflurane by 90-95% (P<0.001 in all cases). Of these compounds, tetraethylammonium chloride and trehalose also alleviated the isoflurane-induced defect in chemotaxis (trehalose by 44%, P=0.001; tetraethylammonium chloride by 23%, P<0.001). In mouse brain, tetraethylammonium chloride reduced isoflurane-induced caspase staining in the anterior cortical (-54%, P=0.007) and hippocampal regions (-46%, P=0.002). DISCUSSION: Tetraethylammonium chloride alleviated isoflurane-induced neurotoxicity in two widely divergent species, raising the likelihood that it may have therapeutic value. In C. elegans, ER stress predicts isoflurane-induced neurotoxicity, but is not its cause.
Assuntos
Isoflurano/toxicidade , Síndromes Neurotóxicas/prevenção & controle , Tetraetilamônio/farmacologia , Anestésicos Inalatórios/toxicidade , Animais , Caenorhabditis elegans , Caspase 3/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Proteínas de Fluorescência Verde/genética , Camundongos , Síndromes Neurotóxicas/etiologia , Especificidade da EspécieRESUMO
BACKGROUND: Targeting fathers may be a key strategy to increase physical activity among their preschool-aged children, but limited research exists in this area. The primary study aim was to examine the impact of a lifestyle program for fathers and their preschool-aged children on child physical activity levels. METHODS: A total of 125 fathers (aged: 38 ± 5.4 years, BMI: 28.1 ± 4.9 kg/m2) and 125 preschool-aged children (aged: 3.9 ± 0.8 years, BMI z-score: 0.3 ± 0.9, 39.2% girls) recruited from Newcastle, Australia, NSW were randomised to (i) the Healthy Youngsters, Healthy Dads (HYHD) program, or (ii) wait-list control group. The program included two fathers-only workshops (2 h each) and eight father-child weekly educational and practical sessions (75 min each), plus home-based activities targeting family physical activity and nutrition. Assessments took place at baseline, 10-weeks (post-intervention) and 9-months follow-up. The primary outcome was the children's mean steps/day at 10-weeks. Secondary outcomes included: co-physical activity, fathers' physical activity levels and parenting practices for physical activity and screen time behaviours, children's fundamental movement skill (FMS) proficiency, plus accelerometer based light physical activity (LPA) and moderate-to-vigorous physical activity (MVPA), screen time and adiposity for fathers and children. Process measures included; attendance, satisfaction, fidelity and retention. Linear mixed models estimated the treatment effect at all time-points for all outcomes. RESULTS: Intention-to-treat analyses revealed a significant group-by-time effect for steps per day at 10-weeks (+ 1417, 95%CI: 449, 2384) and 9-months follow-up (+ 1480, 95%CI: 493, 2467) in intervention children compared to control. There were also favourable group-by-time effects for numerous secondary outcomes including fathers' physical activity levels, children's FMS proficiency, and several parenting constructs. No effects were observed for both fathers' and children's accelerometer based LPA or MVPA, co-physical activity, screen-time and adiposity measures. Process evaluation data revealed very high levels of satisfaction, attendance, retention, and intervention fidelity. CONCLUSION: Engaging fathers in a lifestyle program is a promising strategy to increase physical activity among preschool-aged children. Additional benefits to fathers' physical activity levels, children's FMS proficiency and parenting practices further support the importance of engaging fathers to improve family health outcomes. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRN12619000105145 . Registered 24/01/2019.