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OBJECTIVE: This study aimed to evaluate the relationship between early life stress (ELS) and metabolic risk in healthy young adults and assess the role of health behaviors. METHODS: Young adults aged 18 to 40 years ( N = 190) with no medical conditions or medication usage were recruited from the community. Participants with ELS ( N = 113) had a history of childhood maltreatment, and most also experienced parental loss ( n = 88). Controls ( N = 77) had no history of maltreatment or parental loss. Standardized interviews and self-reports assessed demographics, adversity, medical/psychiatric history, and health behaviors. Blood pressure and anthropometrics were measured, and fasting plasma assayed for lipid profiles, glucose, insulin level, and hemoglobin A 1c . We calculated both a clinical cut-point and continuous composite metabolic risk score based on clinical risk factors and the mean of z scores of each measure, respectively. RESULTS: ELS was significantly associated with increased clinical cut-point ( ß = 0.68, 95% confidence interval [CI] = 0.20-1.17, p = .006) and continuous ( ß = 0.23, 95% CI = 0.08-0.038, p = .003) composite metabolic risk scores. On sensitivity analysis, the association of ELS with the continuous composite metabolic risk score was reduced to a trend after adjusting for a range of psychosocial and health predictors ( ß = 0.18, 95% CI = 0.00-0.36, p = .053), with both diet and college graduate status significant in the model. CONCLUSIONS: Healthy young adults with a history of ELS have increased metabolic risk scores as compared with controls. This relationship may be partially due to health behaviors and socioeconomic factors. These findings underline that ELS is an early contributor to metabolic risk.
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Experiências Adversas da Infância , Doenças Cardiovasculares , Morte Parental , Humanos , Adulto Jovem , Fatores de Risco , Estresse PsicológicoRESUMO
OBJECTIVES: Mitochondrial dysfunction is implicated in the pathophysiology of psychiatric disorders. Levels of circulating cell-free mitochondrial DNA (cf-mtDNA) are observed to be altered in depression. However, the few studies that have measured cf-mtDNA in depression have reported conflicting findings. This study examined cf-mtDNA and depressive symptoms in low-active adults who smoke. METHODS: Participants were adults 18 to 65 years old ( N = 109; 76% female) with low baseline physical activity and depressive symptoms recruited for a smoking cessation study. Self-report measures assessed depression severity, positive and negative affect, and behavioral activation. Blood was collected and analyzed for cf-mtDNA. Relationships between depressive symptoms and cf-mtDNA were examined with correlations and linear regression. RESULTS: Levels of cf-mtDNA were associated with categorically defined depression (Center for Epidemiologic Studies Depression Scale score >15), lower positive affect, and decreased behavioral activation ( p < .05). Relationships remained significant after adjustment for age, sex, and nicotine dependence. In a linear regression model including all depressive symptom measures as predictors, Center for Epidemiologic Studies Depression Scale group and lower positive affect remained significant. CONCLUSIONS: This work suggests that mitochondrial changes are associated with depressive symptoms in low-active adults who smoke. Higher levels of cf-mtDNA in association with depression and with lower positive affect and decreased behavioral activation are consistent with a possible role for mitochondrial function in depressive symptoms.
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Ácidos Nucleicos Livres , Tabagismo , Adulto , Humanos , Feminino , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Idoso , Masculino , Depressão/complicações , DNA Mitocondrial/genética , Mitocôndrias , FumarRESUMO
Childhood adversity is linked to psychological, behavioral, and physical health problems, including obesity and cardiometabolic disease. Epigenetic alterations are one pathway through which the effects of early life stress and adversity might persist into adulthood. Epigenetic mechanisms have also been proposed to explain why cardiometabolic health can vary greatly between individuals with similar Body Mass Index (BMIs). We evaluated two independent cross-sectional cohorts of adults without known medical illness, one of which explicitly recruited individuals with early life stress (ELS) and control participants (n = 195), and the other a general community sample (n = 477). In these cohorts, we examine associations between childhood adversity, epigenetic aging, and metabolic health. Childhood adversity was associated with increased GrimAge Acceleration (GAA) in both cohorts, both utilizing a dichotomous yes/no classification (both p < 0.01) as well as a continuous measure using the Childhood Trauma Questionnaire (CTQ) (both p < 0.05). Further investigation demonstrated that CTQ subscales for physical and sexual abuse (both p < 0.05) were associated with increased GAA in both cohorts, whereas physical and emotional neglect were not. In both cohorts, higher CTQ was also associated with higher BMI and increased insulin resistance (both p < 0.05). Finally, we demonstrate a moderating effect of BMI on the relationship between GAA and insulin resistance where GAA correlated with insulin resistance specifically at higher BMIs. These results, which were largely replicated between two independent cohorts, suggest that interactions between epigenetics, obesity, and metabolic health may be important mechanisms through which childhood adversity contributes to long-term physical and metabolic health effects.
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In seeking to understand mental health and disease, it is fundamental to identify the biological substrates that draw together the experiences and physiological processes that underlie observed psychological changes. Mitochondria are subcellular organelles best known for their central role in energetics, producing adenosine triphosphate to power most cellular processes. Converging lines of evidence indicate that mitochondria play a key role in the biological embedding of adversity. Preclinical research documents the effects of stress exposure on mitochondrial structure and function, and recent human research suggests alterations constituting recalibrations, both adaptive and nonadaptive. Current research suggests dynamic relationships among stress exposure, neuroendocrine signaling, inflammation, and mitochondrial function. These complex relationships are implicated in disease risk, and their elucidation may inform prevention and treatment of stress- and trauma-related disorders. We review and evaluate the evidence for mitochondrial dysfunction as a consequence of stress exposure and as a contributing factor to psychiatric disease.
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Experiências Adversas da Infância , Alostase , Transtornos Mentais , Mitocôndrias , Estresse Psicológico , Alostase/fisiologia , Humanos , Transtornos Mentais/imunologia , Transtornos Mentais/metabolismo , Transtornos Mentais/fisiopatologia , Mitocôndrias/fisiologia , Estresse Psicológico/imunologia , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologiaRESUMO
The subgenual anterior cingulate cortex (subgenual ACC) plays an important role in regulating emotion, and degeneration in this area correlates with depressed mood and anhedonia. Despite this understanding, it remains unknown how this part of the prefrontal cortex causally contributes to emotion, especially positive emotions. Using Pavlovian conditioning procedures in macaque monkeys, we examined the contribution of the subgenual ACC to autonomic arousal associated with positive emotional events. After such conditioning, autonomic arousal increases in response to cues that predict rewards, and monkeys maintain this heightened state of arousal during an interval before reward delivery. Here we show that although monkeys with lesions of the subgenual ACC show the initial, cue-evoked arousal, they fail to sustain a high level of arousal until the anticipated reward is delivered. Control procedures showed that this impairment did not result from differences in autonomic responses to reward delivery alone, an inability to learn the association between cues and rewards, or to alterations in the light reflex. Our data indicate that the subgenual ACC may contribute to positive affect by sustaining arousal in anticipation of positive emotional events. A failure to maintain positive affect for expected pleasurable events could provide insight into the pathophysiology of psychological disorders in which negative emotions dominate a patient's affective experience.
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Sistema Nervoso Autônomo/fisiologia , Giro do Cíngulo/fisiologia , Haplorrinos/fisiologia , Animais , Condicionamento Clássico , Pupila/fisiologiaRESUMO
Although several studies have emphasized the role of the anterior cingulate cortex (ACC) in associating actions with reward value, its role in guiding choices on the basis of changes in reward value has not been assessed. Accordingly, we compared rhesus monkeys with ACC lesions and controls on object- and action-based reinforcer devaluation tasks. Monkeys were required to associate an object or an action with one of two reward outcomes, and we assessed the monkey's shift in choices of objects or actions after changes in the value of 1 outcome. No group differences emerged on either task. For comparison, we tested the same monkeys on their ability to make choices guided by reward contingency in object- and action-based reversal learning tasks. Monkeys with ACC lesions were impaired in using rewarded trials to sustain the selection of the correct object during object reversal learning. They were also impaired in using errors to guide choices in action reversal learning. These data indicate that the role of the ACC is not restricted to linking specific actions with reward outcomes, as previously reported. Instead, the data suggest a more general role for the ACC in using information about reward and nonreward to sustain effective choice behavior.
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Comportamento de Escolha/fisiologia , Giro do Cíngulo/fisiologia , Reversão de Aprendizagem/fisiologia , Recompensa , Animais , Macaca mulatta , Masculino , Reforço PsicológicoRESUMO
OBJECTIVES: We aimed to characterize the interplay between early life stress (ELS), metabolic syndrome (MetS), and plasminogen activator inhibitor-1 (PAI-1), a major inhibitor of the fibrinolytic system implicated in cardiometabolic diseases. We also examined the understudied intersection of ELS, physical activity and PAI-1. METHODS: Healthy young adults ages 18-40 (N=200; 68% female) were recruited from the community. Participants with ELS (N=118) experienced childhood maltreatment, and the majority (n=92) also experienced childhood parental loss. Control participants (N=82) had no history of childhood maltreatment or parental loss. Participants had no current cardiometabolic or thrombotic conditions. Fasting plasma samples were assessed for markers of metabolic risk and total PAI-1 using the Bio-Plex Pro Human Diabetes Panel (Bio-Rad Laboratories). A composite metabolic risk z-score (MetS risk) was computed from the mean standardized z-scores of waist-to-height ratio, systolic and diastolic blood pressure, triglycerides, total cholesterol, LDL and HLD cholesterol, fasting plasma glucose, and hemoglobin A1c. RESULTS: We found that a history of ELS was linked to both higher PAI-1 levels and a higher MetS risk score. ELS was associated with a higher MetS Z-score in adulthood via increased circulating PAI-1 levels (Average Causal Mediation Effect [ACME]= 0.07, p = 0.036). ELS was also linked to increased PAI-1 levels via greater MetS z-scores (ACME = 0.02, p < 0.001). There was a significant interaction effect of ELS and exercise on PAI-1 levels (p = 0.03), such that engaging in higher levels of daily exercise was linked to lower PAI-1 levels in individuals with ELS. CONCLUSION: Healthy young adults with ELS have elevated PAI-1 levels and metabolic risk scores. Among individuals with ELS, exercise is linked to lower PAI-1 levels, suggesting a potential direction for early intervention.
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Síndrome Metabólica , Inibidor 1 de Ativador de Plasminogênio , Humanos , Inibidor 1 de Ativador de Plasminogênio/sangue , Feminino , Adulto , Masculino , Adulto Jovem , Síndrome Metabólica/metabolismo , Síndrome Metabólica/sangue , Adolescente , Estresse Psicológico/metabolismo , Estresse Psicológico/sangue , Exercício Físico/fisiologia , Experiências Adversas da Infância , Biomarcadores/sangue , Fatores de Risco , Pressão Sanguínea/fisiologia , Triglicerídeos/sangueRESUMO
There is limited work examining the association of race and ethnicity with restraint and seclusion (R/S) in pediatric inpatient psychiatric units. The present study assessed risk of R/S by race and ethnicity based on a retrospective review of electronic medical records (EMRs) from an adolescent inpatient psychiatric service. Demographic, diagnostic, and R/S data were analyzed for all 1,865 admissions of 1,327 patients from an adolescent unit at a child and adolescent psychiatric hospital from June 2018 to June 2021. R/S occurred in 459 of the admissions. For the purpose of patient privacy and statistical analysis, race was grouped into the following: Black or African American, other (American Indian or Alaskan Native, Asian, multiracial, other), and White. Patients identified as unknown were not included in the analysis. A binary logistic regression with a repeated subject effect regressed R/S onto race and adjusted for age, gender, and length of stay (LOS). There was an overall significant association of R/S and race (χ22 = 16.81, p < .001), but not ethnicity. In a regression model adjusted for age, gender, and LOS, patients identified as Black or African American were at significantly higher risk of R/S compared with patients identified as White (odds ratio = 1.66, p = .036). There was no significant difference in risk of R/S between patients identified as White vs other. Younger age and longer LOS were also significantly associated with R/S. These findings highlight a critical health care disparity related to race on an inpatient adolescent psychiatry service. There is likely a combination of individual and systemic factors leading to discriminatory practices in the use of R/S. Future work will assess potential associations with diagnosis and child welfare involvement and will examine additional characteristics of R/S. Focus groups held with hospital and community stakeholders will guide next steps to address these findings.
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Psiquiatria do Adolescente , Pacientes Internados , Humanos , Adolescente , Criança , Etnicidade , Hospitalização , Tempo de Internação , Estudos RetrospectivosRESUMO
BACKGROUND: Childhood adversity is a major risk factor for cardiometabolic health problems. Stress-related changes in diet suggest a role for endocrine factors that influence dietary intake, such as leptin and ghrelin. These hormones influence metabolism and may contribute to the relationship of early adversity, mental, and cardiometabolic health. This study examined levels of leptin and ghrelin in a sample of young adults with and without early life stress (ELS). METHODS: Young adults ages 18-40 (N = 200; 68.5% female) were recruited from the community. Participants with ELS (N = 118) had childhood maltreatment, and a subset, n = 92 (78.0%) also had parental loss, and n = 65 (55.1%) also had a current psychiatric disorder. Control participants (N = 82) had no maltreatment, parental loss, or psychiatric disorders. Standardized interviews and self-reports assessed demographics, adversity, medical/psychiatric history, and health behaviors. Exclusion criteria included medical conditions and current medications other than hormonal contraceptives. Body Mass Index (BMI) and other anthropometrics were measured, and fasting plasma was assayed for total ghrelin and leptin with the Bio-Plex Pro Human Diabetes Panel. RESULTS: While ELS was significantly associated with greater leptin (r = .16, p = .025), a finding which held when adjusted for age and sex (F(3196)= 28.32, p = .011), this relationship was abolished when accounting for BMI (p = .44). Participants with ELS also had significantly lower total ghrelin (r = .21, p = .004), which held adjusting for age and sex (p = .002) and was attenuated (p = .045) when the model included BMI (F=46.82, p < .001). Current psychiatric disorder was also a significant predictor of greater leptin (r = .28, p < .001) and lower ghrelin (r = .29, p = .003). In the model with ELS and covariates, psychiatric disorder remained significant (F=7.26, p = .008) and ELS was no longer significant (p = .87). Associations with severity and recent perceived stress were also examined. CONCLUSION: The relationship of ELS and leptin was no longer significant when accounting for BMI, suggesting potential avenues for intervention. Ghrelin findings persisted after correction for BMI, which may be secondary to physiological differences in the regulation of these hormones (leptin is produced by adipocytes, whereas ghrelin is produced primarily in the GI tract). Lastly, these findings suggest that psychiatric functioning may be a key component contributing to the relationship of lower total ghrelin and childhood adversity.
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Experiências Adversas da Infância , Doenças Cardiovasculares , Morte Parental , Humanos , Feminino , Adulto Jovem , Adolescente , Adulto , Masculino , Leptina , Grelina , Índice de Massa CorporalRESUMO
[This corrects the article DOI: 10.1016/j.bbih.2022.100519.].
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BACKGROUND: The COVID-19 pandemic has presented new challenges for physicians, and physician-parents specifically. Few studies have focused on work-life changes in this population. The present study investigated work-life changes in a group of physicians during the first six months of the COVID-19 pandemic. METHODS: A survey was distributed electronically to physicians affiliated with a U.S. medical school inquiring about experiences during the first six months of the COVID-19 pandemic (March 2020 to September 2020). RESULTS: In logistic regression models adjusted for age, significantly more female physician- parents reported increased burnout, increased time with kids, and increased fear of going to work compared to male physician-parents. Around 1 in 2 attendings reported burnout, regardless of parenting status. CONCLUSION: While high rates of burnout were found across all groups in this study, differences were found by gender and parenting status. Further research is needed to understand burnout during the COVID-19 pandemic and to support physician-parents.
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Esgotamento Profissional , COVID-19 , Médicos , Esgotamento Profissional/epidemiologia , COVID-19/epidemiologia , Feminino , Humanos , Satisfação no Emprego , Acontecimentos que Mudam a Vida , Masculino , Pandemias , Poder FamiliarRESUMO
Background and aims: Cell-free DNA (cfDNA) is elevated in several disease states. Metabolic syndrome is a constellation of factors associated with poor cardiometabolic outcomes. This study examined associations of cfDNA from the nucleus (cf-nDNA) and mitochondria (cf-mtDNA), C-reactive protein (CRP), and metabolic syndrome risk, in low-active smokers with depressive symptoms. Methods: Participants (N = 109; mean age 47) self-reported medical history. Physical activity was determined by accelerometry and anthropometrics were measured. Blood was collected and analyzed for cf-nDNA, cf-mtDNA, CRP, triglycerides, high-density lipoprotein, hemoglobin A1c. A continuous metabolic syndrome composite risk score was calculated. Relationships of cf-nDNA, cf-mtDNA, CRP, and cardiometabolic risk were examined with correlations and linear regression. Results: CRP and cf-nDNA were significantly associated with metabolic syndrome risk (r = .39 and r = .31, respectively), cf-mtDNA was not (r = .01). In a linear regression, CRP and cf-nDNA significantly predicted the metabolic syndrome risk score, findings that remained significant controlling for age, gender, nicotine dependence, and physical activity. Conclusions: Associations of cf-nDNA with both CRP and metabolic risk suggest a role for cf-nDNA in inflammatory processes associated with metabolic syndrome. The negative findings for cf-mtDNA suggest distinct roles for cf-nDNA and cf-mtDNA in these processes.
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Early-life adversity (ELA), which includes maltreatment, neglect, or severe trauma in childhood, increases the life-long risk for negative health outcomes. Mitochondria play a key role in the stress response and may be an important mechanism by which stress is transduced into biological risk for disease. By responding to cues from stress-signaling pathways, mitochondria interact dynamically with physiological stress responses coordinated by the central nervous, endocrine, and immune systems. Preclinical evidence suggests that alterations in mitochondrial function and structure are linked to both early stress and systemic biological dysfunction. Early clinical studies support that increased mitochondrial DNA content and altered cellular energy demands may be present in individuals with a history of ELA. Further research should investigate mitochondria as a potential therapeutic target following ELA.
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Mitocôndrias/metabolismo , Estresse Fisiológico , Experiências Adversas da Infância , Animais , Sistema Nervoso Central/metabolismo , Sistema Endócrino/metabolismo , Humanos , Sistema Imunitário/metabolismoRESUMO
Childhood maltreatment is a major risk factor for chronic and severe mental and physical health problems across the lifespan. Increasing evidence supports the hypothesis that maltreatment is associated with epigenetic changes that may subsequently serve as mechanisms of disease. The current review uses a systematic approach to identify and summarize the literature related to childhood maltreatment and alterations in DNA methylation in humans. A total of 100 empirical articles were identified in our systematic review of research published prior to or during March 2020, including studies that focused on candidate genes and studies that leveraged epigenome-wide data in both children and adults. Themes arising from the literature, including consistent and inconsistent patterns of results, are presented. Several directions for future research, including important methodological considerations for future study design, are discussed. Taken together, the literature on childhood maltreatment and DNA methylation underscores the complexity of transactions between the environment and biology across development.
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Maus-Tratos Infantis , Metilação de DNA , Adulto , Criança , Epigênese Genética , Epigenoma , Humanos , Fatores de RiscoRESUMO
BACKGROUND: Maternal diet is an important factor in prenatal development that also has implications for disease risk later in life. The adipokine leptin is a key regulator of energy homeostasis and may be involved in the association between maternal nutrition, maternal obesity, and infant outcomes. DNA methylation of placenta genes may occur in response to exposures and may program subsequent infant development. This study examined maternal diet, placenta leptin gene DNA methylation, and neonatal growth in a sample of healthy neonates and their mothers. METHODS: Mothers and their healthy neonates (N = 135) were recruited within 1-2 days following delivery at Women and Infants Hospital in Providence, RI. A structured interview was conducted to assess maternal dietary intake. Maternal pre-pregnancy weight, weight gain during pregnancy, maternal health, medications, and vitamin use were obtained from medical records. Bisulfite pyrosequencing was used to measure methylation of CpG sites in the promoter region of the placenta leptin gene and determine genotype of the leptin single nucleotide polymorphism (SNP) rs2167270, which is known to influence leptin methylation. Bivariate analyses and linear regression models were used to evaluate associations of demographics, diet, and mean leptin methylation. RESULTS: Genotype was a significant predictor of placenta leptin DNA methylation (p < .01), and after controlling for this and other relevant maternal and infant covariates, lower levels of leptin methylation were significantly associated with greater intake of carbohydrates (p < .05), in particular added sugars (p < .05) and white/refined carbohydrates (p < .05). Total caloric intake was also associated with placenta leptin methylation (p < .05), however after controlling for relevant covariates, significance diminished to trend-level. There were no significant associations of placenta leptin methylation and intake of protein (p > .05) or fat (p > .05). CONCLUSION: These findings underline the importance of intake of carbohydrate consumption for methylation of the placenta leptin gene. Because methylation reduces gene transcription, lower methylation may indicate a placenta response to high caloric intake and carbohydrate food that would result in higher levels of this hormone during fetal development. Further investigation of the developmental ramifications of epigenetic changes to placenta leptin methylation should be pursued.
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Metilação de DNA/genética , Dieta , Leptina/genética , Placenta/metabolismo , Adulto , Feminino , Humanos , Recém-Nascido , Modelos Lineares , Masculino , Modelos Biológicos , Nutrientes/metabolismo , GravidezRESUMO
Neurogenesis persists throughout life in the neurogenic regions of the mature mammalian brain, and this response is enhanced after traumatic brain injury (TBI). In the hippocampus, adult neurogenesis plays an important role in hippocampal-dependent learning and memory functions and is thought to contribute to the spontaneous cognitive recovery observed after TBI. Utilizing an antimitotic agent, arabinofuranosyl cytidine (Ara-C), the current study investigated the direct association of injury-induced hippocampal neurogenesis with cognitive recovery. In this study, adult rats received a moderate lateral fluid percussion injury followed by a 7-day intraventricular infusion of 2% Ara-C or vehicle. To examine the effect of Ara-C on cell proliferation, animals received intraperitoneal injections of 5-bromo-2-deoxyuridine (BrdU), to label dividing cells, and were sacrificed at 7 days after injury. Brain sections were immunostained for BrdU or doublecortin (DCX), and the total number of BrdU(+) or DCX(+) cells in the hippocampus was quantified. To examine the outcome of inhibiting the injury-induced cell proliferative response on cognitive recovery, animals were assessed on Morris water maze (MWM) tasks at 21-25 or 56-60 days postinjury. We found that a 7-day infusion of Ara-C significantly reduced the total number of BrdU(+) and DCX(+) cells in the dentate gyrus (DG) in both hemispheres. Moreover, inhibition of the injury-induced cell proliferative response in the DG completely abolished the innate cognitive recovery on MWM performance at 56-60 days postinjury. These results support the causal relationship of injury-induced hippocampal neurogenesis on cognitive functional recovery and suggest the importance of this endogenous repair mechanism on restoration of hippocampal function.
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Lesões Encefálicas/fisiopatologia , Proliferação de Células/fisiologia , Cognição/fisiologia , Giro Denteado/fisiopatologia , Neurogênese/fisiologia , Recuperação de Função Fisiológica/fisiologia , Animais , Lesões Encefálicas/psicologia , Proliferação de Células/efeitos dos fármacos , Cognição/efeitos dos fármacos , Citarabina/farmacologia , Giro Denteado/efeitos dos fármacos , Proteína Duplacortina , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Neurogênese/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacosRESUMO
Caudal brainstem viscerosensory nuclei convey information about the body's internal state to forebrain regions implicated in feeding behavior and responses to immune challenge, and may modulate ingestive behavior following immune activation. Illness-induced appetite loss might be attributed to accentuated "satiety" pathways, activation of a distinct "danger channel" separate from satiety pathways, or both. To evaluate neural substrates that could mediate the effects of illness on ingestive behavior, we analyzed the pattern and phenotypes of medullary neurons responsive to consumption of a preferred food, sweetened milk, and to intraperitoneal lipopolysaccharide challenge that reduced sweetened milk intake. Brainstem sections were stained for c-Fos, dopamine beta-hydroxylase, phenylethanolamine-N-methyltransferase, and glucagon-like peptide-1 (GLP-1) immunoreactivity. Sweetened milk intake activated many neurons throughout the nucleus of the solitary tract (NTS), including A2 noradrenergic neurons in the caudal half of the NTS. LPS challenge activated a similar population of neurons in the NTS, in addition to rostral C2 adrenergic and mid-level A2 noradrenergic neurons in the NTS, many C1 and A1 neurons in the ventrolateral medulla, and in GLP-1 neurons in the dorsal medullary reticular nucleus. Increased numbers of activated GLP-1 neurons in the NTS were only associated with sweetened milk ingestion. Evidence for parallel processing was reflected in the parabrachial nucleus, where sweetened milk intake resulted in activation of the inner external lateral, ventrolateral and central medial portions, whereas LPS challenge induced c-Fos expression in the outer external lateral portions. Thus, signals generated in response to potentially dangerous physiological conditions seem to be propagated via specific populations of catecholaminergic neurons in the NTS and VLM, and likely include a pathway through the external lateral PBN. The data indicate that immune challenge engages multiple ascending neural pathways including both a distinct catecholaminergic "danger" pathway, and a possibly multimodal pathway derived from the NTS.