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1.
Prev Sci ; 25(6): 919-933, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39138816

RESUMO

In a group randomized trial of 45 elementary schools, a whole-child health and wellness curriculum introduced as a regular part of the educational programming was compared to education as usual over 2 years with a 2-year follow-up. The curriculum focused on integrating multiple SEL skills-mindfulness, compassion, and physical awareness-with the intent to advantage developmental patterns for these skills, academic engagement, personal well-being, and student behavior. The program design and trial implementation were launched with end-use delivery and long-term sustainability as integral considerations. Effects were shown for several SEL skills and behavioral indicators previously robustly correlated to long-term outcomes. Effects were demonstrated more broadly in schools serving high-poverty communities, suggesting the impact was stronger where the need was greater. Results are interpreted regarding supporting school-based SEL, the potential of applying group randomized trials with end-use conditions of implementation, and the value of fitting innovation efforts to school system operations, mandates, and priorities for promoting sustainability.


Assuntos
Promoção da Saúde , Humanos , Criança , Feminino , Masculino , Instituições Acadêmicas , Serviços de Saúde Escolar/organização & administração , Currículo
2.
Early Child Educ J ; 52(2): 243-257, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39092205

RESUMO

Teaching is a demanding profession with teachers of very young children reporting high rates of stress and exhaustion. We tested the effects of a relationship-focused professional development intervention designed to enhance teachers' use of mindfulness-based strategies to support coping on trajectories of teachers' stress, exhaustion (emotional, physical, and mental), and coping. Infant and toddler teachers (N = 81) from Early Head Start (EHS) or EHS childcare partnerships (CCP) were randomized to the intervention or usual care control condition. Using ecological momentary assessment, teachers completed twice-weekly reports of stress, exhaustion, coping, and coping strategy effectiveness via smartphones for 40 weeks. Multilevel linear regression modeling, accounting for within-person repeated measures, showed no intervention effects on stress and exhaustion trajectories. Teachers in the intervention reported increased use of mindfulness-based strategies for coping over time as compared to the control group, although frequency of use peaked and then declined. While perceptions of stress and exhaustion did not change, teachers' increased use of mindfulness-based strategies suggests improvements in how teachers managed stress and exhaustion; however, the decline in use of coping suggests the need for ongoing support within the workplace.

3.
Early Educ Dev ; 34(7): 1545-1564, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37849911

RESUMO

This study described infant/toddler teachers' (N = 106) perceptions of stress intensity and exhaustion (emotional, physical, mental) intensity. We examined the associations between stress and exhaustion and teachers' reports of stress sources and coping strategy use. Using ecological momentary assessment (EMA), teachers from Early Head Start (EHS), EHS childcare-partnerships, or independent childcare programs (midwestern U.S.) completed twice-weekly reports of: stress and exhaustion intensity; stress sources (workload, children's behaviors, personal life); and, coping strategies (support from colleagues, distraction, mindfulness techniques, reframing). Research Findings: Stress and exhaustion reports were similar to studies of preschool teachers. Workload and personal life stressors were associated with stress and all exhaustion types. Teachers used fewer than two different coping strategies/per reporting day. Only reframing was negatively associated with stress and emotional exhaustion. Teachers reported greater stress at end-of-week than beginning-of-week. Older teachers reported greater stress and emotional exhaustion. Although one-third of teachers reported ≥4 ACEs, early adversity was not associated with stress or exhaustion. Practice or Policy: We discuss the results relative to the sparse literature on infant/toddler teachers' well-being and suggest areas for professional development supports while underscoring the need for EHS federal policy makers and program administrators to consider how to reduce/streamline workload.

4.
Mindfulness (N Y) ; : 1-12, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37362185

RESUMO

Objectives: Teachers play a critical role in preparing our children and adolescents for a successful future. However, despite the large number of students impacted by trauma and adversity, teachers are often not well prepared to provide trauma-sensitive support. Furthermore, while working to support students exposed to trauma and adversity, teachers may experience empathy-based stress exacerbating already high levels of stress among them. This narrative review explores the issue of empathy-based stress within the context of the prosocial classroom model which proposes that teachers' social and emotional competence and well-being are key to their ability to create and maintain supportive learning environments critical to student academic and behavioral outcomes. Methods: Recent findings in neuroscience and education research are applied to support teachers' development of these competencies. Results: We propose that shifting from empathy-based stress to compassionate responding may be one such competency to help teachers' respond effectively to their students' needs while protecting their own wellbeing. Conclusion: We review research that supports this proposition and explore implications for teacher professional learning, educational policy, and further research.

5.
Am J Physiol Regul Integr Comp Physiol ; 323(6): R849-R860, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36250633

RESUMO

To date, there has been a lag between the rise in E-cigarette use and an understanding of the long-term health effects. Inhalation of E-cigarette aerosol delivers high doses of nicotine, raises systemic cytokine levels, and compromises cardiopulmonary function. The consequences for muscle function have not been thoroughly investigated. The present study tests the hypothesis that exposure to nicotine-containing aerosol impairs locomotor muscle function, limits exercise tolerance, and interferes with muscle repair in male mice. Nicotine-containing aerosol reduced the maximal force produced by the extensor digitorum longus (EDL) by 30%-40% and, the speed achieved in treadmill running by 8%. Nicotine aerosol exposure also decreased adrenal and increased plasma epinephrine and norepinephrine levels, and these changes in catecholamines manifested as increased muscle and liver glycogen stores. In nicotine aerosol exposed mice, muscle regenerating from overuse injury only recovered force to 80% of noninjured levels. However, the structure of neuromuscular junctions (NMJs) was not affected by e-cigarette aerosols. Interestingly, the vehicle used to dissolve nicotine in these vaping devices, polyethylene glycol (PG) and vegetable glycerin (VG), decreased running speed by 11% and prevented full recovery from a lengthening contraction protocol (LCP) injury. In both types of aerosol exposures, cardiac left ventricular systolic function was preserved, but left ventricular myocardial relaxation was altered. These data suggest that E-cigarette use may have a negative impact on muscle force and regeneration due to compromised glucose metabolism and contractile function in male mice.NEW & NOTEWORTHY In male mice, nicotine-containing E-cigarette aerosol compromises muscle contractile function, regeneration from injury, and whole body running speeds. The vehicle used to deliver nicotine, propylene glycol, and vegetable glycerin, also reduces running speed and impairs the restoration of muscle function in injured muscle. However, the predominant effects of nicotine in this inhaled aerosol are evident in altered catecholamine levels, increased glycogen content, decreased running capacity, and impaired recovery of force following an overuse injury.


Assuntos
Transtornos Traumáticos Cumulativos , Sistemas Eletrônicos de Liberação de Nicotina , Masculino , Animais , Camundongos , Nicotina/farmacologia , Glicerol , Aerossóis/química , Músculo Esquelético
6.
Proc Natl Acad Sci U S A ; 119(7)2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35135884

RESUMO

Mitochondrial inner NEET (MiNT) and the outer mitochondrial membrane (OMM) mitoNEET (mNT) proteins belong to the NEET protein family. This family plays a key role in mitochondrial labile iron and reactive oxygen species (ROS) homeostasis. NEET proteins contain labile [2Fe-2S] clusters which can be transferred to apo-acceptor proteins. In eukaryotes, the biogenesis of [2Fe-2S] clusters occurs within the mitochondria by the iron-sulfur cluster (ISC) system; the clusters are then transferred to [2Fe-2S] proteins within the mitochondria or exported to cytosolic proteins and the cytosolic iron-sulfur cluster assembly (CIA) system. The last step of export of the [2Fe-2S] is not yet fully characterized. Here we show that MiNT interacts with voltage-dependent anion channel 1 (VDAC1), a major OMM protein that connects the intermembrane space with the cytosol and participates in regulating the levels of different ions including mitochondrial labile iron (mLI). We further show that VDAC1 is mediating the interaction between MiNT and mNT, in which MiNT transfers its [2Fe-2S] clusters from inside the mitochondria to mNT that is facing the cytosol. This MiNT-VDAC1-mNT interaction is shown both experimentally and by computational calculations. Additionally, we show that modifying MiNT expression in breast cancer cells affects the dynamics of mitochondrial structure and morphology, mitochondrial function, and breast cancer tumor growth. Our findings reveal a pathway for the transfer of [2Fe-2S] clusters, which are assembled inside the mitochondria, to the cytosol.


Assuntos
Citosol/metabolismo , Compostos Ferrosos/metabolismo , Mitocôndrias/metabolismo , Canal de Ânion 1 Dependente de Voltagem/metabolismo , Animais , Neoplasias da Mama , Linhagem Celular Tumoral , Simulação por Computador , Matriz Extracelular , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Glicólise , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Nus , Neoplasias Experimentais , Consumo de Oxigênio , Canal de Ânion 1 Dependente de Voltagem/genética
7.
Physiol Rep ; 10(3): e15185, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35150208

RESUMO

Pulmonary arterial hypertension (PAH) is associated with significant morbidity and mortality. PAH is characterized by pulmonary artery remodeling, elevated right ventricular pressure (RVP) and, ultimately, cardiac failure. Pulmonary endothelial cells can sense danger or damage caused by mechanical injury or pathogens through alarmin cytokines. These cytokines can signal proliferation to restore barrier integrity or aberrant hyperproliferation and remodeling. We hypothesized that IL-33 signals pulmonary artery endothelial cells to proliferate under hypertensive conditions during the remodeling response and rise in RVP. To test this hypothesis, pulmonary hypertension (PH) was induced in C57Bl/6J, IL-33 receptor gene deleted (ST2-/- ) and MYD88 gene deleted (MYD88-/- ) mice by exposure to 10% O2 and SU5416 injections (SUHX). RVP, arterial wall thickness, endothelial cell proliferation and IL-33 levels and signaling were evaluated. In response to SUHX. RVP increased in C57Bl/6J mice in response to SUHX (49% male and 70% female; p < 0.0001) and this SUHX response was attenuated in ST2-/- mice (29% male p = 0.003; 30% female p = 0.001) and absent in MYD88-/- mice. Wall thickness was increased in SUHX C57Bl/6J mice (p = 0.005), but not in ST2-/- or MYD88-/- mice. Proliferating cells were detected in C57Bl/6J mice by flow cytometry (CD31+ /BrDU+ ; p = 0.02) and immunofluorescence methods (Ki-67+). IL-33 was increased by SUHX (p = 0.03) but a genotype effect was not observed (p = 0.76). We observed that in hPAECs, IL-33 expression is regulated by both IL-33 and DLL4. These data suggest IL-33/ST2 signaling is essential for the endothelial cell proliferative response in PH.


Assuntos
Hipertensão Pulmonar/metabolismo , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Interleucina-33/metabolismo , Transdução de Sinais , Animais , Células Cultivadas , Feminino , Deleção de Genes , Hipertensão Pulmonar/etiologia , Indóis/toxicidade , Proteína 1 Semelhante a Receptor de Interleucina-1/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/genética , Pirróis/toxicidade
8.
J Mol Biol ; 432(9): 3018-3032, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32135193

RESUMO

The methyltransferases that belong to the SpoU-TrmD family contain trefoil knots in their backbone fold. Recent structural dynamic and binding analyses of both free and bound homologs indicate that the knot within the polypeptide backbone plays a significant role in the biological activity of the molecule. The knot loops form the S-adenosyl-methionine (SAM)-binding pocket as well as participate in SAM binding and catalysis. Knots contain both at once a stable core as well as moving parts that modulate long-range motions. Here, we sought to understand allosteric effects modulated by the knotted topology. Uncovering the residues that contribute to these changes and the functional aspects of these protein motions are essential to understanding the interplay between the knot, activation of the methyltransferase, and the implications in RNA interactions. The question we sought to address is as follows: How does the knot, which constricts the backbone as well as forms the SAM-binding pocket with its three distinctive loops, affect the binding mechanism? Using a minimally tied trefoil protein as the framework for understanding the structure-function roles, we offer an unprecedented view of the conformational mechanics of the knot and its relationship to the activation of the ligand molecule. Focusing on the biophysical characterization of the knot region by NMR spectroscopy, we identify the SAM-binding region and observe changes in the dynamics of the loops that form the knot. Importantly, we also observe long-range allosteric changes in flanking helices consistent with winding/unwinding in helical propensity as the knot tightens to secure the SAM cofactor.


Assuntos
Metiltransferases/química , Metiltransferases/metabolismo , S-Adenosilmetionina/metabolismo , Sítio Alostérico , Ligantes , Modelos Moleculares , Simulação de Dinâmica Molecular , Ressonância Magnética Nuclear Biomolecular , Conformação Proteica , Domínios Proteicos , Dobramento de Proteína
9.
Educ Psychol Meas ; 80(2): 262-292, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32158022

RESUMO

Methods to handle ordered-categorical indicators in latent variable interactions have been developed, yet they have not been widely applied. This article compares the performance of two popular latent variable interaction modeling approaches in handling ordered-categorical indicators: unconstrained product indicator (UPI) and latent moderated structural equations (LMS). We conducted a simulation study across sample sizes, indicators' distributions and category conditions. We also studied four strategies to create sets of product indicators for UPI. Results supported using a parceling strategy to create product indicators in the UPI approach or using the LMS approach when the categorical indicators are symmetrically distributed. We applied these models to study the interaction effect between third- to fifth-grade students' social skills improvement and teacher-student closeness on their state English language arts test scores.

10.
Child Dev ; 91(3): e597-e618, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31231803

RESUMO

Mounting evidence suggests teacher-child race/ethnicity matching and classroom diversity benefit Black and Latinx children's academic and socioemotional development. However, less is known about whether the effects of teacher-child matching differ across levels of classroom diversity. This study examined effects of matching on teacher-reported child outcomes in a racially/ethnically diverse sample of teachers and children, and classroom diversity moderation using multilevel models. Data were drawn from a professional learning study involving 224 teachers (Mage  = 41.5) and 5,200 children (Mage  = 7.7) in 36 New York City elementary schools. Teacher-child race/ethnicity matching was associated with higher child engagement in learning, motivation, social skills, and fewer absences. Classroom diversity moderated matching such that teacher-child mismatch was related to lower engagement, motivation, social skills, math and reading scores in low-diversity classrooms, but not in high-diversity classrooms. Implications for practice and policy are discussed.


Assuntos
Desempenho Acadêmico , Negro ou Afro-Americano , Desenvolvimento Infantil , Diversidade Cultural , Hispânico ou Latino , Professores Escolares , Sucesso Acadêmico , Adulto , Criança , Feminino , Humanos , Aprendizagem , Masculino , Motivação , Cidade de Nova Iorque
11.
J Sch Psychol ; 76: 186-202, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31759466

RESUMO

Teacher stress is at an all-time high, negatively impacting the quality of education and student outcomes. In recent years, mindfulness-based interventions have been shown to promote well-being and reduce stress among healthy adults. In particular, mindfulness-based interventions enhance emotion regulation and reduce psychological distress. One such program specifically designed to address teacher stress is Cultivating Awareness and Resilience in Education (CARE). The present study examined teachers' self-reported data collected at three time points over two consecutive school years as part of a randomized controlled trial of CARE. The study involved 224 teachers in 36 elementary schools in high poverty areas of New York City. Teachers were randomly assigned within schools to receive CARE or to a waitlist control group. This study builds on previous experimental evidence of the impacts of CARE on teacher self-reported outcomes for this sample of teachers within one school year (Jennings et al., 2017). Results indicate that at the third assessment point (9.5 months after participating in the program), CARE teachers showed continued significant decreases in psychological distress, reductions in ache-related physical distress, continued significant increases in emotion regulation and some dimensions of mindfulness. Findings indicate that teachers who participated in mindfulness-based professional development through CARE reported both sustained and new benefits regarding their well-being at a follow-up assessment almost one-year post-intervention compared to teachers in the control condition. Implications for further research and policy are discussed.


Assuntos
Regulação Emocional , Atenção Plena/métodos , Estresse Ocupacional/terapia , Angústia Psicológica , Professores Escolares/psicologia , Habilidades Sociais , Adulto , Idoso , Feminino , Seguimentos , Nível de Saúde , Humanos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Atenção Plena/educação , Cidade de Nova Iorque , Saúde Ocupacional , Estresse Ocupacional/psicologia , Resiliência Psicológica , Autorrelato , Resultado do Tratamento
12.
Proc Natl Acad Sci U S A ; 116(40): 19924-19929, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31527235

RESUMO

MitoNEET is an outer mitochondrial membrane protein essential for sensing and regulation of iron and reactive oxygen species (ROS) homeostasis. It is a key player in multiple human maladies including diabetes, cancer, neurodegeneration, and Parkinson's diseases. In healthy cells, mitoNEET receives its clusters from the mitochondrion and transfers them to acceptor proteins in a process that could be altered by drugs or during illness. Here, we report that mitoNEET regulates the outer-mitochondrial membrane (OMM) protein voltage-dependent anion channel 1 (VDAC1). VDAC1 is a crucial player in the cross talk between the mitochondria and the cytosol. VDAC proteins function to regulate metabolites, ions, ROS, and fatty acid transport, as well as function as a "governator" sentry for the transport of metabolites and ions between the cytosol and the mitochondria. We find that the redox-sensitive [2Fe-2S] cluster protein mitoNEET gates VDAC1 when mitoNEET is oxidized. Addition of the VDAC inhibitor 4,4'-diisothiocyanatostilbene-2,2'-disulfonate (DIDS) prevents both mitoNEET binding in vitro and mitoNEET-dependent mitochondrial iron accumulation in situ. We find that the DIDS inhibitor does not alter the redox state of MitoNEET. Taken together, our data indicate that mitoNEET regulates VDAC in a redox-dependent manner in cells, closing the pore and likely disrupting VDAC's flow of metabolites.


Assuntos
Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Oxirredução , Canal de Ânion 1 Dependente de Voltagem/metabolismo , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/química , Animais , Apoptose , Sítios de Ligação , Dimiristoilfosfatidilcolina/química , Ferroptose , Homeostase , Humanos , Ferro/química , Ferro/metabolismo , Proteínas Ferro-Enxofre/metabolismo , Cinética , Mitocôndrias Hepáticas/metabolismo , Membranas Mitocondriais/metabolismo , Oxigênio/química , Conformação Proteica , Mapeamento de Interação de Proteínas , Multimerização Proteica , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Ovinos
13.
Am J Respir Cell Mol Biol ; 61(5): 567-574, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30973786

RESUMO

Chronic obstructive pulmonary disease (COPD) is a worldwide threat. Cigarette smoke (CS) exposure causes cardiopulmonary disease and COPD and increases the risk for pulmonary tumors. In addition to poor lung function, patients with COPD are susceptible to bouts of dangerous inflammation triggered by pollutants or infection. These severe inflammatory episodes can lead to additional exacerbations, hospitalization, further deterioration of lung function, and reduced survival. Suitable models of the inflammatory conditions associated with CS, which potentiate the downward spiral in patients with COPD, are lacking, and the underlying mechanisms that trigger exacerbations are not well understood. Although initial CS exposure activates a protective role for vascular endothelial growth factor (VEGF) functions in barrier integrity, chronic exposure depletes the pulmonary VEGF guard function in severe COPD. Thus, we hypothesized that mice with compromised VEGF production and challenged with CS would trigger human-like severe inflammatory progression of COPD. In this model, we discovered that CS exposure promotes an amplified IL-33 cytokine response and severe disease progression. Our VEGF-knockout model combined with CS recapitulates severe COPD with an influx of IL-33-expressing macrophages and neutrophils. Normally, IL-33 is quickly inactivated by a post-translational disulfide bond formation. Our results reveal that BAL fluid from the CS-exposed, VEGF-deficient cohort promotes a significantly prolonged lifetime of active proinflammatory IL-33. Taken together, our data demonstrate that with the loss of a VEGF-mediated protective barrier, the CS response switches from a localized danger to an uncontrolled long-term and long-range, amplified, IL-33-mediated inflammatory response that ultimately destroys lung function.


Assuntos
Inflamação/metabolismo , Interleucina-33/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Fumar/efeitos adversos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Citocinas/líquido cefalorraquidiano , Citocinas/metabolismo , Humanos , Inflamação/patologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Macrófagos/metabolismo , Camundongos , Nicotiana/efeitos adversos
14.
Chem Sci ; 10(3): 665-673, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30774867

RESUMO

Suppression of apoptosis is a key Hallmark of cancer cells, and reactivation of apoptosis is a major avenue for cancer therapy. We reveal an interaction between the two anti-apoptotic proteins iASPP and NAF-1, which are overexpressed in many types of cancer cells and tumors. iASPP is an inhibitory member of the ASPP protein family, whereas NAF-1 belongs to the NEET 2Fe-2S protein family. We show that the two proteins are stimulated to interact in cells during apoptosis. Using peptide array screening and computational methods we mapped the interaction interfaces of both proteins to residues 764-778 of iASPP that bind to a surface groove of NAF-1. A peptide corresponding to the iASPP 764-780 sequence stabilized the NAF-1 cluster, inhibited NAF-1 interaction with iASPP, and inhibited staurosporine-induced apoptosis activation in human breast cancer, as well as in PC-3 prostate cancer cells in which p53 is inactive. The iASPP 764-780 IC50 value for inhibition of cell death in breast cancer cells was 13 ± 1 µM. The level of cell death inhibition by iASPP 764-780 was altered in breast cancer cells expressing different levels and/or variants of NAF-1, indicating that the peptide activity is associated with NAF-1 function. We propose that the interaction between iASPP and NAF-1 is required for apoptosis activation in cancer cells. This interaction uncovers a new layer in the highly complex regulation of cell death in cancer cells and opens new avenues of exploration into the development of novel anticancer drugs that reactivate apoptosis in malignant tumors.

15.
Prog Brain Res ; 244: 355-385, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30732845

RESUMO

Accumulating research in education shows that contemplative practices contribute to and foster well-being of individuals in sustainable ways. This bears special importance for teachers, as it affects not only them but also their students. Based on accumulating behavioral and neuroscientific findings, it has been suggested that a key process by which mindfulness meditation enhances self-regulation is the altering of self-awareness. Indeed, accumulated work shows that the underlying networks supporting various types of self-awareness are malleable following meditative practice. However, the field of education has developed independently from the study of the self and its relation to contemplative neuroscience thus far, and to date there is no systematic account linking this accumulating body of knowledge to the field of education or discussing how it might be relevant to teachers. Here we show how incorporating insights from contemplative neuroscience-which are built on the conceptualization and neuroscience of the self-into contemplative pedagogy can inform the field and might even serve as a core underlying mechanism tying together different empirical evidence. This review points to potential neural mechanisms by which mindfulness meditation helps teachers manage stress and promote supportive learning environments, resulting in improved educational outcomes, and thus it has significant implications for educational policy regarding teachers.


Assuntos
Conscientização/fisiologia , Encéfalo/fisiologia , Educação , Atenção Plena , Neurociências , Humanos
16.
Antioxid Redox Signal ; 30(8): 1083-1095, 2019 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-29463105

RESUMO

SIGNIFICANCE: Cancer cells accumulate high levels of iron and reactive oxygen species (ROS) to promote their high metabolic activity and proliferation rate. However, high levels of iron and ROS can also lead to enhanced oxidative stress and the activation of cell death pathways such as apoptosis and ferroptosis. This has led to the proposal that different drugs that target iron and/or ROS metabolism could be used as anticancer drugs. However, due to the complex role iron and ROS play in cells, the majority of these drugs yielded mixed results, highlighting a critical need to identify new players in the regulation of iron and ROS homeostasis in cancer cells. Recent Advances: NEET proteins belong to a newly discovered class of iron-sulfur proteins (2Fe-2S) required for the regulation of iron and ROS homeostasis in cells. Recent studies revealed that the NEET proteins NAF-1 (CISD2) and mitoNEET (CISD1) play a critical role in promoting the proliferation of cancer cells, supporting tumor growth and metastasis. Moreover, the function of NEET proteins in cancer cells was found to be dependent of the degree of lability of their 2Fe-2S clusters. CRITICAL ISSUES: NEET proteins could represent a key regulatory link between the maintenance of high iron and ROS in cancer cells, the activation of cell death and survival pathways, and cellular proliferation. FUTURE DIRECTIONS: Because the function of NEET proteins depends on the lability of their clusters, drugs that target the 2Fe2S clusters of NEET proteins could be used as promising anticancer drugs.


Assuntos
Proteínas Ferro-Enxofre/metabolismo , Ferro/metabolismo , Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Homeostase , Humanos , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/metabolismo , Metástase Neoplásica
17.
PLoS One ; 13(8): e0201734, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30125296

RESUMO

Selecting amino acids to design novel protein-protein interactions that facilitate catalysis is a daunting challenge. We propose that a computational coevolutionary landscape based on sequence analysis alone offers a major advantage over expensive, time-consuming brute-force approaches currently employed. Our coevolutionary landscape allows prediction of single amino acid substitutions that produce functional interactions between non-cognate, interspecies signaling partners. In addition, it can also predict mutations that maintain segregation of signaling pathways across species. Specifically, predictions of phosphotransfer activity between the Escherichia coli histidine kinase EnvZ to the non-cognate receiver Spo0F from Bacillus subtilis were compiled. Twelve mutations designed to enhance, suppress, or have a neutral effect on kinase phosphotransfer activity to a non-cognate partner were selected. We experimentally tested the ability of the kinase to relay phosphate to the respective designed Spo0F receiver proteins against the theoretical predictions. Our key finding is that the coevolutionary landscape theory, with limited structural data, can significantly reduce the search-space for successful prediction of single amino acid substitutions that modulate phosphotransfer between the two-component His-Asp relay partners in a predicted fashion. This combined approach offers significant improvements over large-scale mutations studies currently used for protein engineering and design.


Assuntos
Bacillus subtilis/citologia , Bacillus subtilis/genética , Evolução Molecular Direcionada/métodos , Escherichia coli/citologia , Escherichia coli/genética , Transdução de Sinais , Bacillus subtilis/enzimologia , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Escherichia coli/enzimologia , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Modelos Moleculares , Complexos Multienzimáticos/química , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , Mutação , Conformação Proteica
18.
Sci Rep ; 8(1): 4840, 2018 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-29556009

RESUMO

The iron-sulfur (2Fe-2S) binding motif CDGSH appears in many important plant and animal proteins that regulate iron and reactive oxygen metabolism. In human it is found in CISD1-3 proteins involved in diabetes, obesity, cancer, aging, cardiovascular disease and neurodegeneration. Despite the important biological role of the CDGSH domain, its origin, evolution and diversification, are largely unknown. Here, we report that: (1) the CDGSH domain appeared early in evolution, perhaps linked to the heavy use of iron-sulfur driven metabolism by early organisms; (2) a CISD3-like protein with two CDGSH domains on the same polypeptide appears to represent the ancient archetype of CDGSH proteins; (3) the origin of the human CISD3 protein is linked to the mitochondrial endosymbiotic event; (4) the CISD1/2 type proteins that contain only one CDGSH domain, but function as homodimers, originated after the divergence of bacteria and archaea/eukaryotes from their common ancestor; and (5) the human CISD1 and CISD2 proteins diverged about 650-720 million years ago, and CISD3 and CISD1/2 share their descent from an ancestral CISD about 1-1.1 billion years ago. Our findings reveal that the CDGSH domain is ancient in its origin and shed light on the complex evolutionary path of modern CDGSH proteins.


Assuntos
Motivos de Aminoácidos , Evolução Molecular , Ferro/metabolismo , Filogenia , Enxofre/metabolismo , Sequência de Aminoácidos , Proteínas Arqueais/química , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência Conservada , Humanos , Domínios Proteicos
19.
J Biol Inorg Chem ; 23(4): 599-612, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29435647

RESUMO

NEET proteins comprise a new class of [2Fe-2S] cluster proteins. In human, three genes encode for NEET proteins: cisd1 encodes mitoNEET (mNT), cisd2 encodes the Nutrient-deprivation autophagy factor-1 (NAF-1) and cisd3 encodes MiNT (Miner2). These recently discovered proteins play key roles in many processes related to normal metabolism and disease. Indeed, NEET proteins are involved in iron, Fe-S, and reactive oxygen homeostasis in cells and play an important role in regulating apoptosis and autophagy. mNT and NAF-1 are homodimeric and reside on the outer mitochondrial membrane. NAF-1 also resides in the membranes of the ER associated mitochondrial membranes (MAM) and the ER. MiNT is a monomer with distinct asymmetry in the molecular surfaces surrounding the clusters. Unlike its paralogs mNT and NAF-1, it resides within the mitochondria. NAF-1 and mNT share similar backbone folds to the plant homodimeric NEET protein (At-NEET), while MiNT's backbone fold resembles a bacterial MiNT protein. Despite the variation of amino acid composition among these proteins, all NEET proteins retained their unique CDGSH domain harboring their unique 3Cys:1His [2Fe-2S] cluster coordination through evolution. The coordinating exposed His was shown to convey the lability to the NEET proteins' [2Fe-2S] clusters. In this minireview, we discuss the NEET fold and its structural elements. Special attention is given to the unique lability of the NEETs' [2Fe-2S] cluster and the implication of the latter to the NEET proteins' cellular and systemic function in health and disease.


Assuntos
Doença , Saúde , Proteínas Ferro-Enxofre/química , Proteínas Ferro-Enxofre/metabolismo , Dobramento de Proteína , Humanos , Interações Hidrofóbicas e Hidrofílicas , Domínios Proteicos
20.
Stress Health ; 34(2): 278-285, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28990329

RESUMO

Studies show teaching is a highly stressful profession and that chronic work stress is associated with adverse health outcomes. This study analysed physiological markers of stress and self-reported emotion regulation strategies in a group of middle school teachers over 1 year. Chronic physiological stress was assessed with diurnal cortisol measures at three time points over 1 year (fall, spring, fall). The aim of this longitudinal study was to investigate the changes in educators' physiological level of stress. Results indicate that compared to those in the fall, cortisol awakening responses were blunted in the spring. Further, this effect was ameliorated by the summer break. Additionally, self-reported use of the emotion regulation strategy reappraisal buffered the observed blunting that occurred in the spring.


Assuntos
Emoções/fisiologia , Hidrocortisona/metabolismo , Estresse Ocupacional/metabolismo , Estresse Ocupacional/fisiopatologia , Professores Escolares , Autocontrole , Adulto , Doença Crônica , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Saliva , Estações do Ano , Fatores de Tempo
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