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1.
Am J Perinatol ; 41(8): 1106-1112, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38160676

RESUMO

OBJECTIVE: To pilot measurement of hair cortisol concentration (HCC) in pregnant women with opioid use disorder and their infants over time and study the potential utility of hair cortisol as a biomarker of chronic stress in this population. STUDY DESIGN: In this pilot prospective cohort study of mother-infant dyads with and without prenatal opioid exposure, we obtained mother-infant HCCs at delivery and again within 1 to 3 months' postpartum. HCCs were compared between the opioid and control groups and between the two time points. RESULTS: There were no significant differences between opioid and control group maternal or infant HCCs at either time point. However, within the opioid-exposed group, there was a significant increase in infant HCCs across the two time points. CONCLUSION: This pilot study describes our experience with the measurement of HCCs in opioid-exposed mother-infant dyads. KEY POINTS: · Maternal stress impacts fetal and child health.. · Many stressors in pregnant women with opioid use disorder.. · Hair cortisol may be a useful stress biomarker..


Assuntos
Biomarcadores , Cabelo , Hidrocortisona , Transtornos Relacionados ao Uso de Opioides , Estresse Psicológico , Humanos , Hidrocortisona/análise , Hidrocortisona/metabolismo , Feminino , Cabelo/química , Gravidez , Estudos Prospectivos , Adulto , Projetos Piloto , Biomarcadores/análise , Biomarcadores/metabolismo , Recém-Nascido , Estresse Psicológico/metabolismo , Lactente , Complicações na Gravidez , Efeitos Tardios da Exposição Pré-Natal , Estudos de Casos e Controles , Adulto Jovem , Masculino , Analgésicos Opioides/efeitos adversos
2.
J Undergrad Neurosci Educ ; 21(1): A81-A84, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38322045

RESUMO

Pipetting is an important technique used in almost every molecular neuroscience method including but not limited to, PCR, reverse transcription, immunohistochemistry, chromatin immunoprecipitation, and cell culture. The COVID-19 pandemic has robbed the undergraduate population of time to practice in person laboratory techniques. In response, we have devised a standardized, quick, and fun way to instruct students on the fundamentals of pipetting, serial dilutions, and basic statistical analysis. Here, we offer a standardized protocol for instructors to use to teach undergraduates valuable skills while providing friendly competition. We also offer an example of an undergraduate performing the steps of this protocol with example results and the results from three separate undergrads' first two attempts. This exercise provides laboratories with a method to reintroduce undergraduates to lab basics while standardizing the training thereby saving time lost to the pandemic.

3.
J Neurochem ; 158(2): 358-372, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33025573

RESUMO

Molecular abnormalities within the Glucocorticoid Receptor (GR) stress signaling pathway involved in dysfunction of mitochondria and confer vulnerability to stress-related psychiatric disorders. Bcl-2 associated athanogene (Bag-1) is a target for the actions of mood stabilizers. Bag-1 interacts with GR, thereby regulating glucocorticoid function. In this study, we investigate the potential role of Bag-1 in regulating GR translocation into mitochondria. Corticosterone (CORT) treatment significantly enhanced Bag-1/GR complex formation and GR mitochondrial translocation in cultured rat cortical neurons after treatment for 30 min and 24 hr. By contrast, after stimulation with CORT for 3 days, localization of the Bag-1/GR complex and mitochondrial GR were reduced. Similar results were obtained in mice, in which administrated CORT in drinking water for 21 days significantly impaired the GR levels in the mitochondria, while Bag-1 over-expression rescued this reduction. Furthermore, chronic CORT exposure led to anhedonia-like and depression-like behaviors in the sucrose-consumption test and forced swimming test, and these behaviors were rescued by Bag-1 over-expression. These results suggest that Bag-1 mediates GR trafficking to mitochondria and regulates affective resilience in response to a CORT increase and provide potential insight into the mechanisms by which Bag-1 and GR could contribute to the physiology and pathogenesis of psychiatric disorders in response to the change of stress hormone.


Assuntos
Afeto/efeitos dos fármacos , Corticosterona/farmacologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Mitocôndrias/metabolismo , Receptores de Glucocorticoides/metabolismo , Resiliência Psicológica/efeitos dos fármacos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Anedonia , Animais , Depressão/psicologia , Relação Dose-Resposta a Droga , Feminino , Masculino , Neurônios/efeitos dos fármacos , Gravidez , Cultura Primária de Células , Transporte Proteico , Ratos , Ratos Sprague-Dawley , Estimulação Química , Natação/psicologia
4.
Front Neuroendocrinol ; 56: 100802, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31738947

RESUMO

The ability to adapt to stressful circumstances, known as emotional resilience, is a key factor in the maintenance of mental health. Several individual biomarkers of the stress response (e.g., corticosterone) that influence an animal's position along the continuum that ranges from adaptive allostasis to maladaptive allostatic load have been identified. Extending beyond specific biomarkers of stress responses, however, it is also important to consider stress-related responses relative to other relevant responses for a thorough understanding of the underpinnings of adaptive allostasis. In this review, behavioral, neurobiological, developmental and genomic variables are considered in the context of emotional resilience [e.g., explore/exploit behavioral tendencies; DHEA/CORT ratios and relative proportions of protein-coding/nonprotein-coding (transposable) genomic elements]. As complex and multifaceted relationships between pertinent allostasis biomediators are identified, translational applications for optimal resilience are more likely to emerge as effective therapeutic strategies.


Assuntos
Estresse Fisiológico/fisiologia , Estresse Psicológico/fisiopatologia , Adaptação Fisiológica/fisiologia , Adaptação Psicológica/fisiologia , Corticosteroides/fisiologia , Alostase/fisiologia , Animais , Comportamento/fisiologia , Encéfalo/fisiopatologia , Desidroepiandrosterona/fisiologia , Feminino , Humanos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Masculino , Sistemas Neurossecretores/fisiopatologia , Resiliência Psicológica
5.
Dev Psychobiol ; 63(2): 237-246, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32311073

RESUMO

While experimental stress paradigms of infants (arm restraint; the Still-Face) are powerful tools for infant research, no study has experimentally stressed mothers to observe its independent effects on infant stress regulation. Extant caretaker/maternal stress studies essentially are correlational and confounded by other conditions (e.g., depression). Here, we present a standard procedure, the Caregiver Acute Stress Paradigm (CASP), for stressing mothers during en face interactions with their infants. We hypothesized that infants of the stressed mothers would be more distressed than infants of non-stressed mothers. A total of 106 four-month-old infants and their mothers were randomly assigned to the experimental stress or non-stress manipulation. Confirming our hypothesis, infants of the stressed mothers were significantly more likely to become distressed and require terminating the procedure. While objective ratings of maternal behavior showed no difference between groups, mother in the stress condition self-rated the episode following the caretaker stress significantly lower than mothers in the non-stress group. The self-ratings in the maternal stress-group were reflected in infant cortisol. The findings indicate that CASP is an effective experimental paradigm for exploring the independent effects of an acute stress on caretakers, including effects of conditions, such as poverty or mental illness.


Assuntos
Relações Mãe-Filho , Mães , Emoções , Feminino , Humanos , Hidrocortisona , Lactente , Comportamento do Lactente , Comportamento Materno
6.
Horm Behav ; 126: 104822, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32730760

RESUMO

Oxytocin is important for postnatal developmental experiences for mothers, infants, and transactions between them. Oxytocin is also implicated in adult affiliative behaviors, including social buffering of stress. There is evidence for connections between early life experience and adult oxytocin system functioning, but effects of early experience on behavioral, endocrine, and neurophysiological outcomes related to adult social buffering are not well explored. We use a limited bedding and nesting (LBN) material paradigm as an environmental disruption of early experiences and assessed central oxytocin systems in brain regions related to hypothalamic-pituitary-adrenal (HPA) axis regulation (paraventricular nucleus of the hypothalamus, amygdala, hippocampus). We also assessed developmentally-appropriate social behaviors and HPA reactivity during social buffering testing in adulthood. LBN litters had larger huddles and more pups visible compared to control litters during the first two weeks of life. LBN also altered the developmental trajectory of oxytocin-expressing cells and oxytocin receptor cells, with increases in oxytocin receptor cells at P15 in LBN pups. By adulthood, LBN females had more and LBN males had fewer oxytocin and oxytocin receptor cells in these areas compared to sex-matched controls. Adult LBN females, but not LBN males, had behavioral changes during social interaction and social buffering testing. The sex-specific effects of early experience on central oxytocin systems and social behavior may contribute to female resilience to early life adversity.


Assuntos
Sistema Hipotálamo-Hipofisário , Comportamento Materno/fisiologia , Ocitocina/metabolismo , Sistema Hipófise-Suprarrenal , Receptores de Ocitocina/metabolismo , Animais , Animais Recém-Nascidos , Comportamento Animal/fisiologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Feminino , Sistema Hipotálamo-Hipofisário/crescimento & desenvolvimento , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Comportamento de Nidação/fisiologia , Ocitocina/farmacologia , Núcleo Hipotalâmico Paraventricular/metabolismo , Sistema Hipófise-Suprarrenal/crescimento & desenvolvimento , Sistema Hipófise-Suprarrenal/metabolismo , Ratos , Ratos Long-Evans , Caracteres Sexuais , Comportamento Social , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologia , Estresse Psicológico/prevenção & controle
7.
Dev Psychobiol ; 62(1): 116-122, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31342518

RESUMO

Neonatal abstinence syndrome (NAS) after in-utero opioid exposure remains a poorly understood condition with multiple factors contributing to severity. Exposure to maternal stress may be one contributing factor. Hair cortisol measurement represents a novel technique for assessing prenatal stress. In this pilot study, the association between maternal hair cortisol levels and NAS severity was examined in 70 postpartum women with opioid use disorder within 72 hr of delivery. Infants were monitored for NAS and treated according to institutional protocol. Forty-four (63%) of the infants were pharmacologically treated for NAS, with a mean length of hospital stay (LOS) for all infants of 14.2 (SD 9.0) days. The mean cortisol level in the mothers was 131.8 pg/mg (SD 124.7). In bivariate analysis, higher maternal hair cortisol levels were associated with shorter infant LOS (R = -.26, p = .03) and fewer infant opioid treatment days (R = -.28, p = .02). Results were no longer statistically significant in regression models after adjusting for maternal opioid and smoking. In conclusion, we demonstrated the feasibility of hair cortisol assaying within the first few days after delivery in mothers with opioid use disorder as a novel marker for NAS. The findings suggest that maternal stress may impact the severity of infant opioid withdrawal.


Assuntos
Cabelo/metabolismo , Hidrocortisona/metabolismo , Mães , Síndrome de Abstinência Neonatal/diagnóstico , Síndrome de Abstinência Neonatal/terapia , Transtornos Relacionados ao Uso de Opioides/complicações , Efeitos Tardios da Exposição Pré-Natal , Estresse Psicológico/metabolismo , Adulto , Estudos de Viabilidade , Feminino , Humanos , Recém-Nascido , Projetos Piloto , Gravidez , Índice de Gravidade de Doença , Adulto Jovem
8.
Mol Biol Evol ; 35(10): 2435-2453, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30053206

RESUMO

Expression of transposable elements (TE) is transiently activated during human preimplantation embryogenesis in a developmental stage- and cell type-specific manner and TE-mediated epigenetic regulation is intrinsically wired in developmental genetic networks in human embryos and embryonic stem cells. However, there are no systematic studies devoted to a comprehensive analysis of the TE transcriptome in human adult organs and tissues, including human neural tissues. To investigate TE expression in the human Dorsolateral Prefrontal Cortex (DLPFC), we developed and validated a straightforward analytical approach to chart quantitative genome-wide expression profiles of all annotated TE loci based on unambiguous mapping of discrete TE-encoded transcripts using a de novo assembly strategy. To initially evaluate the potential regulatory impact of DLPFC-expressed TE, we adopted a comparative evolutionary genomics approach across humans, primates, and rodents to document conservation patterns, lineage-specificity, and colocalizations with transcription factor binding sites mapped within primate- and human-specific TE. We identified 654,665 transcripts expressed from 477,507 distinct loci of different TE classes and families, the majority of which appear to have originated from primate-specific sequences. We discovered 4,687 human-specific and transcriptionally active TEs in DLPFC, of which the prominent majority (80.2%) appears spliced. Our analyses revealed significant associations of DLPFC-expressed TE with primate- and human-specific transcription factor binding sites, suggesting potential cross-talks of concordant regulatory functions. We identified 1,689 TEs differentially expressed in the DLPFC of Schizophrenia patients, a majority of which is located within introns of 1,137 protein-coding genes. Our findings imply that identified DLPFC-expressed TEs may affect human brain structures and functions following different evolutionary trajectories. On one side, hundreds of thousands of TEs maintained a remarkably high conservation for ∼8 My of primates' evolution, suggesting that they are likely conveying evolutionary-constrained primate-specific regulatory functions. In parallel, thousands of transcriptionally active human-specific TE loci emerged more recently, suggesting that they could be relevant for human-specific behavioral or cognitive functions.


Assuntos
Elementos de DNA Transponíveis , Genoma Humano , Córtex Pré-Frontal/metabolismo , Primatas/metabolismo , Esquizofrenia/etiologia , Adulto , Idoso , Animais , Estudos de Casos e Controles , Biologia Computacional , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Ratos , Roedores/metabolismo , Esquizofrenia/metabolismo , Fatores de Transcrição/metabolismo
9.
Front Neuroendocrinol ; 49: 170-174, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29551355

RESUMO

The brain is responsible for both recognition and adaptation to stressful stimuli. Many molecular mechanisms have been implicated in this response including those governing neuronal plasticity, neurogenesis and, changes gene expression. Far less is known regarding effects of stress on the deep genome. In the hippocampus, stress appears to regulate expression of non-coding elements of the genome as well as the chromatin permissive for their transcription. Specifically, hippocampal retrotransposon (RT) elements are regulated by acute stress via the accumulation of the repressive H3K9me3 mark at RT loci. Further, corticosteroids appear to induce changes in heterochromatin status as well as RT expression in both adrenalectomized animal and rat cell culture models. Dysregulation of RT expression is predicted to result in functional deficits in affected brain areas. More broadly, however, transposons may have a variety of adaptive functions. As techniques improve to probe the deep genome, this approach to understanding stress neurobiology has the potential to yield insights into environment and genome interactions that may contribute to the physiology underlying a number of stress-related mental health disorders.


Assuntos
Epigênese Genética/fisiologia , Genoma/fisiologia , Hipocampo/metabolismo , RNA não Traduzido/metabolismo , Retroelementos/fisiologia , Estresse Psicológico/metabolismo , Animais , Humanos
10.
Proc Natl Acad Sci U S A ; 113(32): 9099-104, 2016 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-27457949

RESUMO

Glucocorticoids (GCs) are involved in stress and circadian regulation, and produce many actions via the GC receptor (GR), which is classically understood to function as a nuclear transcription factor. However, the nuclear genome is not the only genome in eukaryotic cells. The mitochondria also contain a small circular genome, the mitochondrial DNA (mtDNA), that encodes 13 polypeptides. Recent work has established that, in the brain and other systems, the GR is translocated from the cytosol to the mitochondria and that stress and corticosteroids have a direct influence on mtDNA transcription and mitochondrial physiology. To determine if stress affects mitochondrially transcribed mRNA (mtRNA) expression, we exposed adult male rats to both acute and chronic immobilization stress and examined mtRNA expression using quantitative RT-PCR. We found that acute stress had a main effect on mtRNA expression and that expression of NADH dehydrogenase 1, 3, and 6 (ND-1, ND-3, ND-6) and ATP synthase 6 (ATP-6) genes was significantly down-regulated. Chronic stress induced a significant up-regulation of ND-6 expression. Adrenalectomy abolished acute stress-induced mtRNA regulation, demonstrating GC dependence. ChIP sequencing of GR showed that corticosterone treatment induced a dose-dependent association of the GR with the control region of the mitochondrial genome. These findings demonstrate GR and stress-dependent transcriptional regulation of the mitochondrial genome in vivo and are consistent with previous work linking stress and GCs with changes in the function of brain mitochondria.


Assuntos
Corticosterona/farmacologia , DNA Mitocondrial/genética , Regulação da Expressão Gênica , Hipocampo/metabolismo , Receptores de Glucocorticoides/fisiologia , Estresse Psicológico/metabolismo , Animais , Masculino , Mitocôndrias/fisiologia , NADH Desidrogenase/genética , RNA Mensageiro/análise , RNA Mitocondrial , Ratos , Ratos Sprague-Dawley
11.
Proc Natl Acad Sci U S A ; 112(22): 6828-33, 2015 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-25385609

RESUMO

Stress plays a substantial role in shaping behavior and brain function, often with lasting effects. How these lasting effects occur in the context of a fixed postmitotic neuronal genome has been an enduring question for the field. Synaptic plasticity and neurogenesis have provided some of the answers to this question, and more recently epigenetic mechanisms have come to the fore. The exploration of epigenetic mechanisms recently led us to discover that a single acute stress can regulate the expression of retrotransposons in the rat hippocampus via an epigenetic mechanism. We propose that this response may represent a genomic stress response aimed at maintaining genomic and transcriptional stability in vulnerable brain regions such as the hippocampus. This finding and those of other researchers have made clear that retrotransposons and the genomic plasticity they permit play a significant role in brain function during stress and disease. These observations also raise the possibility that the transposome might have adaptive functions at the level of both evolution and the individual organism.


Assuntos
Epigênese Genética/fisiologia , Regulação da Expressão Gênica/fisiologia , Hipocampo/metabolismo , Modelos Biológicos , Retroelementos/fisiologia , Esteroides/metabolismo , Estresse Fisiológico/fisiologia , Animais , Plasticidade Neuronal/fisiologia , Ratos
12.
Adv Exp Med Biol ; 978: 145-166, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28523545

RESUMO

Anxiety disorders are highly prevalent psychiatric disorders often comorbid with depression and substance abuse. Twin studies have shown that anxiety disorders are moderately heritable. Yet, genome-wide association studies (GWASs) have failed to identify gene(s) significantly associated with diagnosis suggesting a strong role for environmental factors and the epigenome. A number of anxiety disorder subtypes are considered "stress related." A large focus of research has been on the epigenetic and anxiety-like behavioral consequences of stress. Animal models of anxiety-related disorders have provided strong evidence for the role of stress on the epigenetic control of the hypothalamic-pituitary-adrenal (HPA) axis and of stress-responsive brain regions. Neuroepigenetics may continue to explain individual variation in susceptibility to environmental perturbations and consequently anxious behavior. Behavioral and pharmacological interventions aimed at targeting epigenetic marks associated with anxiety may prove fruitful in developing treatments.


Assuntos
Transtornos de Ansiedade/genética , Ansiedade/genética , Epigênese Genética/genética , Adolescente , Corticosteroides/fisiologia , Adulto , Animais , Ansiolíticos/uso terapêutico , Ansiedade/tratamento farmacológico , Ansiedade/etiologia , Ansiedade/psicologia , Transtornos de Ansiedade/tratamento farmacológico , Transtornos de Ansiedade/etiologia , Transtornos de Ansiedade/psicologia , Criança , Modelos Animais de Doenças , Suscetibilidade a Doenças , Doenças em Gêmeos/genética , Feminino , Estudo de Associação Genômica Ampla , Humanos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Padrões de Herança , Plasticidade Neuronal , Sistema Hipófise-Suprarrenal/fisiopatologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Estresse Psicológico , Estudos em Gêmeos como Assunto
13.
Proc Natl Acad Sci U S A ; 111(45): 16130-5, 2014 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-25349423

RESUMO

Genetic evidence suggests cell-type-specific functions for certain nucleoporins, and gene expression profiling has revealed that nucleoporin p62 (NUP62) transcripts are decreased in the prefrontal cortex of major depressives. Chronic stress, which can precipitate depression, induces changes in the architecture and plasticity of apical dendrites that are particularly evident in the CA3 region of the hippocampus. Genetically targeted translating ribosome affinity purification revealed a selective reduction in translated Nup62 transcripts in CA3 of chronically stressed mice, and the Nup62 protein content of nuclei extracted from whole hippocampus was found to be decreased in chronically stressed rats. In cultured cells, phosphorylation of a FAK/proline-rich tyrosine kinase 2 (PYK2) consensus site in the alpha-helical domain of NUP62 (human Y422) is shown to be associated with shedding of NUP62 from the nuclear pore complex (NPC) and/or retention of NUP62 in the cytoplasm. Increased levels of phospho-Y425 Nup62 were observed in cytoplasmic fractions of hippocampi from chronically stressed rats, and immunofluorescence microscopy revealed redistribution of activated Pyk2 to the perinuclear region of stressed pyramidal neurons. Depletion of Nup62 from cultured embryonic day 18 rat hippocampal and cortical neurons resulted in simplification and retraction of dendritic arbors, without disruption of axon initial segment integrity. Thus, at least two types of mechanisms--one affecting expression and the other association with the NPC--could contribute to loss of NUP62 from CA3 pyramidal neurons during chronic stress. Their combined actions may account for the enhanced responsiveness of CA3 apical dendrites to chronic stress and may either be pathogenic or serve to protect CA3 neurons from permanent damage.


Assuntos
Região CA3 Hipocampal/metabolismo , Quinase 2 de Adesão Focal/metabolismo , Glicoproteínas de Membrana/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Células Piramidais/metabolismo , Estresse Psicológico/metabolismo , Animais , Axônios/metabolismo , Axônios/patologia , Região CA3 Hipocampal/patologia , Doença Crônica , Dendritos/metabolismo , Dendritos/patologia , Quinase 2 de Adesão Focal/genética , Humanos , Glicoproteínas de Membrana/genética , Camundongos , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Células Piramidais/patologia , Ratos , Ratos Sprague-Dawley , Estresse Psicológico/genética , Estresse Psicológico/patologia
14.
Am J Bot ; 102(1): 85-91, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25587151

RESUMO

UNLABELLED: • PREMISE OF STUDY: Accurate demographic information about long-lived plant species is important for understanding responses to large-scale disturbances, including climate change. It is challenging to obtain these data from desert perennial plants because seedling establishment is exceptionally rare, and estimates of survival are lacking for their vulnerable early stages. Desert wildfires, urbanization, and climate change influence the persistence of the long-lived Yucca brevifolia. Quantitative demographic attributes are crucial for understanding how populations will respond to disturbances and where populations will recede or advance under future climate scenarios.• METHODS: We measured survival in a cohort of 53 pre-reproductive Y. brevifolia at Yucca Flat, Nevada, USA, for 22 yr and recorded their growth, nurse-plant relationships, and herbivory.• KEY RESULTS: Herbivory by black-tailed jackrabbits (Lepus californicus) caused severe losses of plants during the first and second years (45% and 31%, respectively). Surviving plants experienced <2.5% annual mortality. Survival for the population was 19% over 22 yr. Plants <25 cm in height had lower life expectancy. Average growth rate (± SD) for plants that survived to the last census was 3.12 ± 1.96 cm yr(-1), and growth rates were positively associated with precipitation. Thirty-year-old Y. brevifolia had not yet reproduced.• CONCLUSIONS: A rare establishment event for Y. brevifolia during 1983-1984, triggered by above-average summer rainfall, provided a unique opportunity to track early survival and growth. Infrequent but acute episodes of herbivory during drought influenced demography for decades. Variability in survival among young Y. brevifolia indicates that size-dependent demographic variables will improve forecasts for this long-lived desert species under predicted regional climate change.


Assuntos
Meio Ambiente , Yucca/fisiologia , Mudança Climática , Chuva , Reprodução , Estações do Ano , Yucca/crescimento & desenvolvimento
15.
Proc Natl Acad Sci U S A ; 109(43): 17657-62, 2012 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-23043114

RESUMO

The hippocampus is a highly plastic brain region particularly susceptible to the effects of environmental stress; it also shows dynamic changes in epigenetic marks in response to stress and learning. We have previously shown that, in the rat, acute (30 min) restraint stress induces a substantial, regionally specific, increase in hippocampal levels of the repressive histone H3 lysine 9 trimethylation (H3K9me3). Because of the large magnitude of this effect and the fact that stress can induce the expression of endogenous retroviruses and transposable elements in many systems, we hypothesized that the H3K9me3 response was targeted to these elements as a means of containing potential genomic instability. We used ChIP coupled with next generation sequencing (ChIP-Seq) to determine the genomic localization of the H3K9me3 response. Although there was a general increase in this response across the genome, our results validated this hypothesis by demonstrating that stress increases H3K9me3 enrichment at transposable element loci and, using RT-PCR, we demonstrate that this effect represses expression of intracisternal-A particle endogenous retrovirus elements and B2 short interspersed elements, but it does not appear to have a repressive effect on long interspersed element RNA. In addition, we present data showing that the histone H3K9-specific methyltransferases Suv39h2 is up-regulated by acute stress in the hippocampus, and that this may explain the hippocampal specificity we observe. These results are a unique demonstration of the regulatory effect of environmental stress, via an epigenetic mark, on the vast genomic terra incognita represented by transposable elements.


Assuntos
Inativação Gênica , Hipocampo/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Retroelementos , Estresse Fisiológico , Animais , Imunoprecipitação da Cromatina , Corticosterona/administração & dosagem , DNA/metabolismo , Histonas/química , Masculino , Metilação , Ratos , Ratos Sprague-Dawley , Receptores de Glucocorticoides/metabolismo
16.
J Am Coll Health ; : 1-9, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546669

RESUMO

OBJECTIVE: To examine both psychiatric risk and psychological wellbeing in a college student sample drawn from a majority-minority university. PARTICIPANTS: 100 participants (42% White; 70 females), mean age, 21.22 years. METHODS: Univariate and multivariate analyses examined the relationship of psychiatric risk (Brief Symptom Inventory; BSI) and psychological wellbeing (Mental Health Continuum-Short Form; MHC-SF) with student stress, cognition, Adverse Childhood Experiences (ACEs) and a new Positive Childhood Experiences (PCEs) scale. RESULTS: Risk correlated with increased student stress, higher ACEs and lower PCEs, whereas wellbeing correlated with lower student stress, better neuropsychological functioning, lower ACE and increased PCEs. PCEs predicted enhanced MHC-SF wellbeing and reduced BSI risk, accounting for 22.4% and 13.7% of variance in these measures, respectively. ACEs predicted elevated BSI risk and diminished MHC-SF wellbeing accounting for 8.6% and 5.9% of variance in these measures, respectively. CONCLUSION: College student mental health may benefit from practices aim specifically to enhance wellbeing, stress-resistance, and cognition.

17.
Neurobiol Stress ; 23: 100522, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36816533

RESUMO

Glucocorticoids are a key component to the cellular response to stress. Glucocorticoids act via glucocorticoid receptors found ubiquitously in the brain and body. Glucocorticoid receptors can bind to response elements throughout the genome to elicit changes in transcription, an adaptation observed at the cellular level. Yet, the transcriptional changes as a consequence of glucocorticoid receptor activation are variable across brain regions, stress conditions and recurrent bouts of glucocorticoid exposure. Here we describe a non-coding RNA, B2 SINE, which is regulated by glucocorticoids and can in turn regulate glucocorticoid receptor transcriptional activity. We show that activated glucocorticoid receptors interact directly with B2 SINE RNA via a decoy response element contained within the transcript sequence and alter receptor binding to response elements in the genome and, subsequently, changes in loci expression.

18.
Curr Top Behav Neurosci ; 63: 241-289, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36029460

RESUMO

Schizophrenia is a complex neurodevelopmental disorder with as-yet no identified cause. The use of animals has been critical to teasing apart the potential individual and intersecting roles of genetic and environmental risk factors in the development of schizophrenia. One way to recreate in animals the cognitive impairments seen in people with schizophrenia is to disrupt the prenatal or neonatal environment of laboratory rodent offspring. This approach can result in congruent perturbations in brain physiology, learning, memory, attention, and sensorimotor domains. Experimental designs utilizing such animal models have led to a greatly improved understanding of the biological mechanisms that could underlie the etiology and symptomology of schizophrenia, although there is still more to be discovered. The implementation of the Research and Domain Criterion (RDoC) has been critical in taking a more comprehensive approach to determining neural mechanisms underlying abnormal behavior in people with schizophrenia through its transdiagnostic approach toward targeting mechanisms rather than focusing on symptoms. Here, we describe several neurodevelopmental animal models of schizophrenia using an RDoC perspective approach. The implementation of animal models, combined with an RDoC framework, will bolster schizophrenia research leading to more targeted and likely effective therapeutic interventions resulting in better patient outcomes.


Assuntos
Transtornos Cognitivos , Esquizofrenia , Animais , Gravidez , Feminino , Esquizofrenia/tratamento farmacológico , Cognição , Transtornos Cognitivos/tratamento farmacológico , Atenção , Modelos Animais de Doenças
19.
Genes (Basel) ; 14(4)2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-37107616

RESUMO

Early life stress (ELS) can have wide-spread neurodevelopmental effects with support accumulating for the idea that genomic mechanisms may induce lasting physiological and behavioral changes following stress exposure. Previous work found that a sub-family of transposable elements, SINEs, are repressed epigenetically after acute stress. This gives support to the concept that the mammalian genome may be regulating retrotransposon RNA expression allowing for adaptation in response to environmental challenges, such as maternal immune activation (MIA). Transposon (TE) RNAs are now thought to work at the epigenetic level and to have an adaptive response to environmental stressors. Abnormal expression of TEs has been linked to neuropsychiatric disorders like schizophrenia, which is also linked to maternal immune activation. Environmental enrichment (EE), a clinically utilized intervention, is understood to protect the brain, enhance cognitive performance, and attenuate responses to stress. This study examines the effects of MIA on offspring B2 SINE expression and further, the impact that EE, experienced throughout gestation and early life, may have in conjunction with MIA during development. Utilizing RT-PCR to quantify the expression of B2 SINE RNA in the juvenile brain of MIA exposed rat offspring, we found dysregulation of B2 SINE expression associated with MIA in the prefrontal cortex. For offspring experiencing EE, the prefrontal cortex exhibited an attenuation of the MIA response observed in standard housed animals. Here, the adaptive nature of B2 is observed and thought to be aiding in the animal's adaptation to stress. The present changes indicate a wide-spread stress-response system adaptation that impacts not only changes at the genomic level but potentially observable behavioral impacts throughout the lifespan, with possible translational relevance to psychotic disorders.


Assuntos
Comportamento Animal , Efeitos Tardios da Exposição Pré-Natal , Animais , Feminino , Ratos , Comportamento Animal/fisiologia , Encéfalo , Efeitos Tardios da Exposição Pré-Natal/genética , Roedores , Elementos Nucleotídeos Curtos e Dispersos
20.
Neurobiol Stress ; 24: 100538, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37139465

RESUMO

Animal models of maternal immune activation (MIA) are central to identifying the biological mechanisms that underly the association between prenatal infection and neuropsychiatric disorder susceptibility. Many studies, however, have limited their scope to protein coding genes and their role in mediating this inherent risk, while much less attention has been directed towards exploring the roles of the epigenome and transposable elements (TEs). In Experiment 1, we demonstrate the ability of MIA to alter the chromatin landscape of the placenta. We induced MIA by injecting 200 µg/kg (i.p.) of lipopolysaccharide (LPS) on gestational day 15 in Sprague-Dawley rats. We found a sex-specific rearrangement of heterochromatin 24-h after exposure to MIA, as evidenced by an increase in histone-3 lysine-9 trimethylation (H3K9me3). In Experiment 2, MIA was associated with long-term sensorimotor processing deficits as indicated by reduced prepulse inhibition (PPI) of the acoustic startle reflex in adult male and female offspring and an increased mechanical allodynia threshold in males. Analyses of gene expression within the hypothalamus-chosen for its involvement in the sex-specific pathogenesis of schizophrenia and the stress response-revealed significantly higher levels of the stress-sensitive genes Gr and Fkbp5. Deleterious TE expression is often a hallmark of neuropsychiatric disease and we found sex-specific increases in the expression of several TEs including IAP, B2 SINE, and LINE-1 ORF1. The data from this study warrant the future consideration of chromatin stability and TEs as part of the mechanism that drives MIA-associated changes in the brain and behavior.

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