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1.
Georgian Med News ; (290): 127-131, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31322529

RESUMO

Corticoliberin (CRF) isn't only regulates hypothalamic-pituitary-adrenal axis activity, but also functions as a neurotransmitter in extrahypothalamic brain regions like amygdala, implicated in the emotional responses to stress. The CRF system provides an input to orexin neurons and can modulate the activity of orexinergic neurons in stress response. Some data showed the role of orexin-A in extinction of aversive memory. The orexin system was shown to participate in stress-induced behavior connected with the extended amygdala structures, like central nucleus of the amygdala. The objective was to study the effects of orexin-A antagonist SB-408124 in rats after predator-induced stress using behavioral tests and its effects on CRF level in amygdala. In this study 30 male Wistar rats were used. The animals received an intranasally selective antagonist of Orexin receptor 1 type SB-408124. Posttraumatic stress disorder was modelled by single predator exposure. A group of 10-12 rats were placed in a terrarium with an indian python. 7 days after exposure to the predator, the behavior of animals was tested in the Open Field and Elevated Cross-Maze tests. Free motor activity of animals was studied in the "open field" test. To assess stress, we used the "elevated cross-maze " test. CRF concentrations in brain structures were measured by solid-phase ELISA using the Corticotropin Releasing Factor (CRF) test system. In the group of stressed rats receiving intranasally SB-408124, the time of stay in the light arm was restored, but did not reach the control values, the number of runs was restored to the control level, and the number of grooming acts increased in comparison with both the control group and the stressed animals. In the "open field" in the group of stressed rats receiving saline solution, the number of sniffs and rearing were decreased, but the number of peeks into holes was increased. In the group of stressed rats receiving SB-408124 20 µg intranasally, the number of sniffs was increased and the number of hole peeking decreased in comparison with the stressed rats receiving saline solution. The CRF level in the homogenates of amygdala in stressed rats was lower (0.44±0.07 ng/mg protein vs. 0.61±0.01 ng/mg in the control group). In the intranasal administration of SB408124 group this decrease was not recorded and the CRF level in the amygdala was 0.57±0.01 pg/mg protein. Orexin A antagonist SB-408124 reduced anxiety after psychotraumatic exposure. Predator induced acute psychotraumatic exposure decrease CRF level in the rat's amygdala. Intranasal administration of selective orexin 1 receptor antagonist SB408124 restored it closely to normal and has an anxiolytic effect on animal behaviour.


Assuntos
Tonsila do Cerebelo/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Hormônio Liberador da Corticotropina/farmacologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Receptores de Orexina , Compostos de Fenilureia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Tonsila do Cerebelo/fisiologia , Animais , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/fisiologia , Ratos , Ratos Wistar , Transtornos de Estresse Pós-Traumáticos/induzido quimicamente
2.
Life Sci ; 232: 116605, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31254588

RESUMO

AIM: The present study was designed to investigate the possible role of T-type Ca2+ channels and HCN channels in the development of stress adaptation in cold-water immersion stress-subjected mice. MATERIAL AND METHODS: The mice were subjected to cold-water immersion stress by placing them individually in a water tank (depth = 15.5 cm; temperature = 15 ±â€¯2 °C) for 5 min. The mice were subjected to single episode of cold-water immersion stress for inducing acute stress; while for inducing stress adaptation, mice were subjected to repeated episodes of homotypic stressor (5 min) for 5 consecutive days. Animals were administered with ethosuximide (100 and 200 mg/kg, i.p.) and ivabradine (5 and 10 mg/kg, i.p.) before subjecting them to stress for five days. The stress-related behavioral alterations were assessed using the actophotometer, the hole board, the open field and the social interaction tests. The plasma corticosterone levels were quantified as a biochemical parameter of hypothalamic-pituitary-adrenal (HPA) axis activation. RESULTS: Acute stress altered the behavioral and biochemical parameters of the animals. However, repeated stress significantly restored the behavioral and biochemical alterations signifying the development of adaptation. Administration of ethosuximide and ivabradine abolished the restoration of behavioral and biochemical changes in the animals subjected to repeated stress. CONCLUSION: The ethosuximide and ivabradine mediated attenuation of stress adaptation demonstrates that the opening of T-type Ca2+ channels and activation of HCN channels are involved in inducing stress adaptation in repeated stress-subjected animals.


Assuntos
Canais de Cálcio Tipo T/fisiologia , Resposta ao Choque Frio/fisiologia , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/fisiologia , Aclimatação/fisiologia , Adaptação Fisiológica , Adaptação Psicológica/fisiologia , Animais , Comportamento Animal/fisiologia , Canais de Cálcio Tipo T/metabolismo , Temperatura Baixa , Corticosterona/sangue , Etossuximida/farmacologia , Sistema Hipotálamo-Hipofisário/fisiologia , Ivabradina/farmacologia , Camundongos , Sistema Hipófise-Suprarrenal/fisiologia , Estresse Fisiológico/fisiologia , Estresse Psicológico/fisiopatologia
3.
Sci Data ; 6(1): 87, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197171

RESUMO

Chinese sturgeon (Acipenser sinensis), a critically endangered Acipenseridae family member, is one of the largest anadromous, native fish in China. Numerous research programmes and protection agencies have focused on breeding and preserving this endangered species. However, available information is limited on the different stages of sex development, especially on the reproductive regulation of the hypothalamus-pituitary-gonad (HPG) axis of A. sinensis. To unravel the mechanism of gene interactions during sex differentiation and gonad development of A. sinensis, we performed transcriptome sequencing using HPG samples from male and female A. sinensis in two developmental stages. In this study, 271.19 Gb high-quality transcriptome data were obtained from 45 samples belonging to 15 individuals (six in stage I, six males and three females in stage II). These transcriptomic data will help us understand the reproductive regulation of the HPG axis in the development stages of A. sinensis and provide important reference data for genomic and genetic studies in A. sinensis and related species.


Assuntos
Espécies em Perigo de Extinção , Peixes/fisiologia , Perfilação da Expressão Gênica , Sistema Hipotálamo-Hipofisário/fisiologia , Diferenciação Sexual/genética , Animais , Feminino , Peixes/genética , Genoma , Masculino , Transcriptoma
4.
Food Chem Toxicol ; 129: 13-21, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31014900

RESUMO

Cadmium (Cd) has been generally recognized as an endocrine-disrupting chemical for its toxic effects on the hypothalamus-pituitary-gonadal (HPG) axis accompanied by dysfunction in sex hormone secretion. Particularly, exposure to Cd during puberty versus post-puberty exhibits differing age-dependent effects that require further examination. This study sought to determine if cyanidin-3-O-glucoside (C3G), a typical anthocyanin with neuroprotective bioactivity, could protect against Cd-induced sex hormone-disorder in Pubertal male mice. C3G treatment reversed the disruption of hormone levels and increased Gnrh1 gene expression in the hypothalamus. In addition, the levels of gonadotropins, including luteinizing hormone (LH) and follicle stimulating hormone (FSH), were reversed by C3G. Interestingly, C3G improved the expression of LH and FSH receptor in the testis in mice exposed to Cd. Furthermore, C3G activated the signaling pathway related to the synthesis of testosterone processing. In conclusion, C3G protected against Cd-induced dysfunction of sex hormone secretion through the regulation of the HPG axis in male mice during puberty. The results of this study suggest that consumption of anthocyanins can be protective against metal-induced male reproductive dysfunction.


Assuntos
Antocianinas/farmacologia , Cádmio/toxicidade , Glucosídeos/farmacologia , Hormônios Esteroides Gonadais/metabolismo , Gônadas/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Maturidade Sexual , Animais , Peso Corporal/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Gônadas/fisiologia , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Camundongos
5.
J Sports Sci ; 37(14): 1655-1662, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30836829

RESUMO

Genetic factors are known to influence sport performance. The aim of the present study was to assess genetic variants in genes coding for proteins potentially modulating activity of brain emotion centres in a group of 621 elite athletes (212 endurance, 183 power and 226 combat athletes) and 672 sedentary controls. Ten statistically significant variants were identified in genes encoding elements of serotoninergic, catecholaminergic and hypothalamic-pituitary-adrenal systems in different sport groups. Of those the rs860573 variant in the FEV gene coding for transcription factor exclusively expressed in neurons of the central serotonin system is the only one whose frequency significantly differentiates all the groups of athletes studied, regardless of discipline, from the controls (p = 0.000026). Our results support the hypothesis that genetic variants potentially affecting mental processes and emotions, particularly in the serotonergic pathway, also influence the predispositions to athletic performance.


Assuntos
Desempenho Atlético/fisiologia , Emoções/fisiologia , Polimorfismo de Nucleotídeo Único , Receptores de Serotonina/genética , Adulto , Ansiedade/genética , Proteínas de Ligação a DNA/genética , Feminino , Genótipo , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Proteínas Nucleares/genética , Sistema Hipófise-Suprarrenal/fisiologia , Polônia , Receptor 5-HT1B de Serotonina/genética , Receptor 5-HT2C de Serotonina/genética , Receptores de Catecolaminas/genética , Estresse Psicológico/genética , Adulto Jovem
6.
Behav Neurosci ; 133(2): 203-211, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30907618

RESUMO

Stress elicits a variety of psychophysiological responses that show large interindividual variability. Determining the neural mechanisms that mediate individual differences in the emotional response to stress would provide new insight that would have important implications for understanding stress-related disorders. Therefore, the present study examined individual differences in the relationship between brain activity and the emotional response to stress. In the largest stress study to date, 239 participants completed the Montreal Imaging Stress Task (MIST) while heart rate, skin conductance response (SCR), cortisol, self-reported stress, and blood oxygen level dependent (BOLD) functional MRI (fMRI) signal responses were measured. The relationship between differential responses (heart rate, SCR, cortisol, and self-reported stress) and differential BOLD fMRI data was analyzed. Dorsolateral prefrontal cortex (PFC), dorsomedial PFC, ventromedial PFC, and amygdala activity varied with the behavioral response (i.e., SCR and self-reported stress). These results suggest the PFC and amygdala support processes that are important for the expression and regulation of the emotional response to stress, and that stress-related PFC and amygdala activity underlie interindividual variability in peripheral physiologic measures of the stress response. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Tonsila do Cerebelo/fisiologia , Emoções/fisiologia , Individualidade , Córtex Pré-Frontal/fisiologia , Estresse Psicológico , Adolescente , Mapeamento Encefálico , Feminino , Resposta Galvânica da Pele , Frequência Cardíaca , Humanos , Hidrocortisona/análise , Sistema Hipotálamo-Hipofisário/fisiologia , Imagem por Ressonância Magnética , Masculino , Sistema Hipófise-Suprarrenal/fisiologia , Testes Psicológicos , Adulto Jovem
7.
Clín. salud ; 30(1): 21-31, mar. 2019.
Artigo em Espanhol | IBECS | ID: ibc-180395

RESUMO

Los bebés expuestos a altos niveles de ansiedad materna durante la etapa prenatal pueden desarrollar un eje HPA (hipotálamo pituitario adrenal) más reactivo, lo que supone vulnerabilidad a padecer psicopatologías. En este estudio prospectivo investigamos las relaciones entre la ansiedad prenatal maternal, el desarrollo psicológico infantil y la reactividad del eje HPA en bebés de 2 a 3 meses. Recogimos datos de cuarenta y seis díadas de madres y bebés. El análisis principal no reveló relaciones significativas entre las tres variables estudiadas, pero la variabilidad apuntó a que la ansiedad materna prenatal podría asociarse a efectos diferenciales en la reactividad del eje HPA en función del desarrollo psicológico infantil. Además, los resultados indicaron que las madres con ansiedad prenatal presentaban otros síntomas psicopatológicos, como sensibilidad interpersonal (p < .001) y obsesión-compulsión (p < .001). Esto es significativo para futuras investigaciones y a nivel clínico para promover intervenciones psicológicas durante la gestación


Babies exposed to high levels of maternal anxiety during the prenatal period may develop a more reactive HPA (hypothalamic-pituitary-adrenal) axis, which poses a vulnerability to psychopathology. In this prospective study, we investigated the relationships between antenatal maternal anxiety, infant psychological developmen,t and HPA axis reactivity in 2 to 3-month-old babies. We use data from forty-six mother-child dyads. The main analysis did not reveal significant relationships between the variables studied, but the variability pointed out that antenatal maternal anxiety could be associated with differential effects on the reactivity of the HPA axis according to the child’s psychological development. In addition, the results indicated that mothers with prenatal anxiety presented other psychopathological symptoms, such as interpersonal sensitivity (p < .001) and obsession-compulsion (p < .001). This is significant for future research and - at a clinical level - to promote psychological interventions during pregnancy


Assuntos
Humanos , Masculino , Feminino , Lactente , Sistema Hipotálamo-Hipofisário/fisiologia , Transtornos de Ansiedade/fisiopatologia , Desenvolvimento Fetal/fisiologia , Hidrocortisona , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Desenvolvimento Infantil/fisiologia
8.
J Sports Sci ; 37(11): 1296-1307, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30786846

RESUMO

The metabolic and hormonal consequences of high-intensity functional training regimens such as CrossFit® (CF) are unclear. Little is known about the triggers and clinical and biochemical features of CF-related overtraining syndrome (OTS). The EROS study compared endocrine and metabolic responses, and eating, social, psychological and body characteristics of OTS-affected (OTS) and healthy athletes (ATL), and non-physically active controls (NPAC). The current study is a post-hoc analysis of the CF subgroups of the EROS study, to evaluate specific characteristics of CF in ATL and OTS. Parameters were overall and pairwise compared among OTS-affected (CF-OTS) and healthy (CF-ATL) athletes that exclusively practiced CF, and NPAC. CF-ATL yielded earlier and enhanced cortisol, GH, and prolactin responses to an insulin tolerance test (ITT), increased neutrophils, lower lactate, increased testosterone, improved sleep quality, better psychological performance, increased measured-to-predicted basal metabolic rate (BMR) ratio and fat oxidation, and better hydration, when compared to NPAC. Conversely, more than 90% of the adaptive changes in CF were lost under OTS, including an attenuation of the hormonal responses to an ITT, increased estradiol, decreased testosterone, and decreased BMR and fat oxidation; the most remarkable trigger of OTS among "HIFT athletes" was the long-term low carbohydrate and calorie intake.


Assuntos
Transtornos Traumáticos Cumulativos/etiologia , Transtornos Traumáticos Cumulativos/metabolismo , Condicionamento Físico Humano/efeitos adversos , Condicionamento Físico Humano/métodos , Adolescente , Adulto , Afeto/fisiologia , Biomarcadores/metabolismo , Fenômenos Biomecânicos , Catecolaminas/urina , Transtornos Traumáticos Cumulativos/fisiopatologia , Técnicas de Diagnóstico Endócrino , Estradiol/sangue , Hormônio do Crescimento Humano/sangue , Humanos , Hidrocortisona/análise , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/fisiologia , Insulina/sangue , Ácido Láctico/sangue , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/fisiologia , Prolactina/sangue , Saliva/química , Sono/fisiologia , Testosterona/sangue , Adulto Jovem
9.
Biol Res Nurs ; 21(2): 157-165, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30700110

RESUMO

OBJECTIVE: We examined genomic variation potentially associated with the cortisol stress response in children having a painful medical procedure. DESIGN: Children 4-10 years old having a peripheral intravenous line inserted provided saliva samples for evaluation of the cortisol response as a biological measure of distress: two on the day of the procedure and two at home on a nonstressful day for comparison values. Children and biological parents also provided samples for genotyping of variants with known or suspected association with the cortisol stress response. Analysis included child-only association and family-based transmission disequilibrium tests (TDTs). RESULTS: Genotype and phenotype data on the cortisol stress response were available from 326 children for child-only association analyses and 376 complete family trios for TDTs. Children were 50% female, an average of 7.5 years old, and mostly (83%) White/non-Hispanic. We identified four single-nucleotide polymorphisms (SNPs) potentially associated with the cortisol stress response: rs1176744 ( HTR3B), rs10062367 ( CRHBP), rs634479 ( OPRM1), and rs8030107 ( NTRK3). Family-based analysis identified a two-SNP haplotype in HTR1B suggestive for association with the cortisol response (rs6296, rs11568817). Allelic TDTs identified rs7897947 ( NFKB2) as potentially related to cortisol response. CONCLUSIONS: Findings provide preliminary evidence for genes potentially important in cortisol response to an acute stressor in children in the serotonin, dopamine, and brain-derived neurotrophic factor pathways, the hypothalamic-pituitary-adrenal axis, and the inflammatory response. Combined with analyses of related phenotypes and clinical data, these results could help identify patients at increased risk of adverse responses to painful medical procedures who might benefit from tailored interventions.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/fisiologia , Variação Genética , Hidrocortisona/genética , Hidrocortisona/metabolismo , Estresse Psicológico/genética , Estresse Psicológico/fisiopatologia , Adulto , Alelos , Criança , Pré-Escolar , Feminino , Genótipo , Haplótipos , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Pais , Fenótipo , Sistema Hipófise-Suprarrenal/fisiologia , Polimorfismo de Nucleotídeo Único
10.
Curr Psychiatry Rep ; 21(2): 7, 2019 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-30729361

RESUMO

PURPOSE OF REVIEW: Prenatal maternal psychological distress is an established risk factor for the development of psychopathology in offspring. The purpose of this review is to evaluate whether sex differences in fetal responses to maternal distress contribute to sex differences in subsequent psychopathology. RECENT FINDINGS: Male and female fetuses respond differently to stress signals. We review recent evidence that demonstrates a sex-specific pattern of association between prenatal maternal distress and pathways associated with risk for psychopathology including offspring hypothalamic pituitary adrenocortical (HPA) axis regulation, brain development, and negative emotionality. Prenatal maternal distress exerts sex-specific consequences on the fetus. These differences may contribute to the well-established sex differences in psychopathology and in particular to greater female vulnerability to develop internalizing problems.


Assuntos
Feto/fisiologia , Complicações na Gravidez/psicologia , Efeitos Tardios da Exposição Pré-Natal/psicologia , Psicopatologia , Caracteres Sexuais , Estresse Psicológico/psicologia , Criança , Feminino , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Sistema Hipófise-Suprarrenal/fisiologia , Gravidez , Fatores de Risco
11.
Nan Fang Yi Ke Da Xue Xue Bao ; 39(1): 125-126, 2019 Jan 30.
Artigo em Chinês | MEDLINE | ID: mdl-30692078

RESUMO

Thyroglobulin is the most important and abundant protein in thyroid follicles and has been widely studied as a tumor marker of thyroid cancer recurrence and persistence. Tg is considered the material basis of thyroid hormone synthesis and does not participate in the regulation of thyroid hormone synthesis and secretion. This review summarizes the recent progress in the research of thyroid hormone synthesis and secretion regulation via a negative feedback regulation mechanism by the thyroid-hypothalamus-pituitary axis. Thyroglobulin can negatively regulate the synthesis of thyroid hormone by thyroid follicular cells and antagonize the positive regulation of thyrotropin TSH. The function of thyroid follicular cells is presumably a result of Tg and TSH interaction, and a follicular cycle model is proposed to explain the causes of follicular heterogeneity in glands. We also discuss the prospects and clinical significance of studies into the negative feedback regulation mechanism of the thyroid-hypothalamus-pituitary axis and compare two theories for this mechanism.


Assuntos
Sistema Hipotálamo-Hipofisário/fisiologia , Recidiva Local de Neoplasia , Tireoglobulina/metabolismo , Glândula Tireoide/fisiologia , Retroalimentação Fisiológica , Humanos , Hormônios Tireóideos/metabolismo , Tireotropina/metabolismo
12.
Vitam Horm ; 109: 341-359, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30678862

RESUMO

Exposure to stressful experiences triggers the release of-among others-glucocorticoids from the adrenal glands. These hormones, cortisol and corticosterone in humans and rodents respectively, activate mineralocorticoid receptors (MRs) and glucocorticoid receptors (GRs) that regulate neuronal activity and behavioral adaptation to stressful experiences. This review discusses molecular properties of MRs, the role of MRs in regulating neuronal function and behavior and, ultimately, evidence that enhanced MR function may confer resilience to stressful experiences.


Assuntos
Encéfalo/metabolismo , Sistema Hipotálamo-Hipofisário/fisiologia , Sistema Hipófise-Suprarrenal/fisiologia , Receptores de Mineralocorticoides/metabolismo , Estresse Fisiológico , Animais , Humanos
13.
J Affect Disord ; 246: 619-626, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30609411

RESUMO

BACKGROUND: This study investigated the efficacy of a succulent, Caralluma fimbriata extract (CFE) in reducing anxiety and stress in healthy adults. METHODS: An 8 week double-blind randomised clinical trial, in which 97 adults self-reporting mild to moderate anxiety were given 500 mg b.d. CFE (n = 49), or 500 mg b.d. placebo (n = 48). Anxiety and stress were measured at baseline, week 4, and week 8 to investigate the timing of treatment effect using the GAD-7, Perceived Stress Scale (PSS), Positive and Negative Affect Schedule (PANAS), and salivary cortisol. Data were analysed using mixed ANOVAs on SPSS v.24. RESULTS: Results indicated a significant reduction in anxiety and stress in both groups at week 4 and week 8. The reduction in the CFE group was significantly greater (p < .05) than in the placebo group on the GAD-7 and PSS at week 4 and week 8, and in Negative affect at week 4. Improvement in Positive affect was greater in the CFE group than in the placebo group at week 8. Cortisol analysis indicated that CFE may act through the Hypothalamic-Pituitary-Adrenal (HPA) axis, showing statistically significant changes in males, but not in females. LIMITATIONS: Self-reported instruments involve subjective interpretation thus salivary cortisol was employed as a more objective measure. The study would benefit from a larger sample and longer trial, and the inclusion of a wait-list group to allow comparison between treatment and no treatment. CONCLUSIONS: The findings indicate that CFE is superior to placebo in reducing subclinical anxiety and stress over 8 weeks.


Assuntos
Transtornos de Ansiedade/tratamento farmacológico , Apocynaceae/química , Fitoterapia , Extratos Vegetais/uso terapêutico , Estresse Psicológico/tratamento farmacológico , Adolescente , Adulto , Idoso , Transtornos de Ansiedade/fisiopatologia , Método Duplo-Cego , Feminino , Humanos , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/fisiologia , Estresse Psicológico/fisiopatologia , Adulto Jovem
14.
Biol Res Nurs ; 21(1): 80-106, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30198309

RESUMO

The objectives of this literature review were to (1) synthesize biological processes linked to frailty and their corresponding biomarkers and (2) identify potential associations among these processes and biomarkers. In September 2016, PubMed, Cumulative Index to Nursing and Allied Health, Cochrane Library, and Embase were searched. Studies examining biological processes related to frailty in older adults (≥60 years) were included. Studies were excluded if they did not employ specific measures of frailty, did not report the association between biomarkers and frailty, or focused on nonelderly samples (average age < 60). Review articles, commentaries, editorials, and non-English articles were also excluded. Fifty-two articles were reviewed, reporting six biological processes related to frailty and multiple associated biomarkers. The processes (biomarkers) include brain changes (neurotrophic factor, gray matter volume), endocrine dysregulation (growth hormones [insulin-like growth factor-1 and binding proteins], hormones related to glucose and insulin, the vitamin D axis, thyroid function, reproductive axis, and hypothalamic-pituitary-adrenal axis), enhanced inflammation (C-reactive protein, interleukin-6), immune dysfunction (neutrophils, monocytes, neopterin, CD8+CD28-T cells, albumin), metabolic imbalance (micronutrients, metabolites, enzyme-activity indices, metabolic end products), and oxidative stress (antioxidants, telomere length, glutathione/oxidized glutathione ratio). Bidirectional interrelationships exist within and between these processes. Biomarkers were associated with frailty in varied strengths, and the causality remains unclear. In conclusion, frailty is related to multisystem physiological changes. Future research should examine the dynamic interactions among these processes to inform causality of frailty. Given the multifactorial nature of frailty, a composite index of multisystem biomarkers would likely be more informative than single biomarkers in early detection of frailty.


Assuntos
Biomarcadores/análise , Idoso Fragilizado , Fragilidade/fisiopatologia , Sistema Hipotálamo-Hipofisário/fisiologia , Sistema Hipófise-Suprarrenal/fisiologia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biológicos , Feminino , Humanos , Masculino
15.
Theriogenology ; 123: 108-115, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30296651

RESUMO

The biological function of inhibin is mediated by two heterodimers, inhibin-A and inhibin-B. The relative importance of inhibin-A and -B in male reproductive function varies considerably across species with inhibin-B predominating in many species, whereas inhibin-A appears relatively more important in rams. Research reported to date in stallions has examined total or immunoreactive (ir) inhibin which does not distinguish the two heterodimers. Therefore, the objective of this study was to characterize changes in inhibin-A and inhibin-B concentrations in stallions: 1) across season for a period of one year, and 2) after downregulation of the hypothalamic-pituitary-gonadal (HPG) axis. In Study one, serum samples were obtained monthly from five stallions for a period of one year. Serum concentrations of inhibin-A, inhibin-B, testosterone and estrone sulfate were determined by ELISA. In Study two, stallions were treated with the GnRH antagonist, acyline (n = 4; 330 mg/kg acyline IM) or vehicle control (n = 4; vehicle alone) every five days for 50 days. Plasma concentrations of inhibin-A and -B were determined by ELISA at Days 0, 6, 12, 22, 37, 59, 80, 87 and 104 after initiation of acyline treatment. Testis volume was determined by ultrasonography at weekly intervals. In Study 1, both inhibin-A and inhibin-B showed seasonal changes in concentration with highest concentrations in increasing day length and lowest concentrations in short day lengths. Inhibin-B (overall mean 107.8 ±â€¯4.1 pg/mL) was present at 4.7-fold higher concentrations in serum than inhibin-A (overall mean 23.0 ±â€¯0.7 pg/mL). In Study 2, plasma concentrations of inhibin-B but not inhibin-A were significantly downregulated by administration of the GnRH antagonist, acyline. When the HPG axis was downregulated by acyline, testis volume was strongly correlated with inhibin-B (r = 0.73; P < 0.05) but not inhibin-A (r = 0.22; P = 0.20). In summary, inhibin-B appears to be the predominant form of inhibin in the stallion which undergoes seasonal regulation along with other reproductive parameters and is co-regulated with other endocrine parameters of the HPG axis.


Assuntos
Cavalos/fisiologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Inibinas/metabolismo , Testículo/efeitos dos fármacos , Animais , Regulação para Baixo , Estrona/análogos & derivados , Estrona/sangue , Cavalos/sangue , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Oligopeptídeos/administração & dosagem , Oligopeptídeos/farmacologia , Distribuição Aleatória , Estações do Ano , Testículo/fisiologia , Testosterona/sangue
16.
Theriogenology ; 123: 167-176, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30308393

RESUMO

Hungarian White geese are regarded as good producers of meat, eggs, and feathers, but specific lighting schedules are required to improve their egg-laying performance. This study reveals the neuroendocrine regulatory mechanisms that govern the reproductive activities and egg-laying performances of Hungarian White geese. The results indicated that increasing the daily photoperiod from a short 8 h period to either 11 h or 14 h initiated reproduction. Egg-laying rates increased faster in the 14 h group, peaking (48.2%) on day 33 as compared to the peak (52.67%) reached on day 53 in the 11 h group. Changes to the plasma estradiol and progesterone concentrations produced similar patterns in the two groups. In the hypothalamus, OPN5, Dio2, c-Fos, and GnRH-I expression levels showed similar sequential increases and decreases. Changes in GnIH and VIP expression levels were the opposite to those of GnRH-I, but the levels peaked earlier under the 14 h photoperiod conditions. Pituitary LH beta and FSH beta expression levels increased at slower rates but remained significantly higher in the 11 h group than in the 14 h group. However, pituitary PRL expression increased considerably earlier and was higher in 14 h geese than in 11 h geese, which was opposite to the observed egg-laying rate patterns. An increase from a short to a relatively long photoperiod (11 h) regulated the neuroendocrine system and led to reproductive activities being sustained for a longer period, which resulted in high egg-laying performances.


Assuntos
Anseriformes/fisiologia , Oviposição/fisiologia , Fotoperíodo , Animais , Peso Corporal , Estradiol/sangue , Feminino , Regulação da Expressão Gênica/efeitos da radiação , Sistema Hipotálamo-Hipofisário/fisiologia , Folículo Ovariano , Ovário/fisiologia , Progesterona/sangue
17.
BMC Psychiatry ; 18(1): 396, 2018 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-30572854

RESUMO

BACKGROUND: The number of people with Internet gaming addiction (IGA) is increasing around the world. IGA is known to be associated with personal characteristics, psychosocial factors, and physiological factors. However, few studies have examined the genetic factors related to IGA. This study aimed to investigate the association between IGA and stress-related genetic variants. METHODS: This cross-sectional study was conducted with 230 male high school students in a South Korean city. We selected five stress-related candidate genes: DAT1, DRD4, NET8, CHRNA4, and CRHR1. The DAT1 and DRD4 genes were genotyped by polymerase chain reaction, and the NET8, CHRNA4, and CRHR1 genes were genotyped by pyrosequencing analysis. We performed a Chi-square test to examine the relationship of these five candidate genes to IGA. RESULTS: Having the AA genotype and the A allele of the CRHR1 gene (rs28364027) was associated with higher odds of belonging to the IGA participant group (p = .016 and p = .021, respectively) than to the non-IGA group. By contrast, the DAT1, DRD4, NET8, and CHRNA4 gene polymorphisms showed no significant difference between the IGA group and control group. CONCLUSIONS: These results indicate that polymorphism of the CRHR1 gene may play an important role in IGA susceptibility in the Korean adolescent male population. These findings provide a justification and foundation for further investigation of genetic factors related to IGA.


Assuntos
Comportamento Aditivo , Jogos Recreativos/psicologia , Receptores de Hormônio Liberador da Corticotropina/genética , Adolescente , Comportamento Aditivo/genética , Comportamento Aditivo/psicologia , Correlação de Dados , Estudos Transversais , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Internet , Masculino , Sistema Hipófise-Suprarrenal/fisiologia , Polimorfismo de Nucleotídeo Único , República da Coreia/epidemiologia
18.
Gen Comp Endocrinol ; 267: 183-192, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30031732

RESUMO

Severe weather events are increasing worldwide because of climate change. To cope with severe weather events, vertebrates rely on the stress response which is activated by the hypothalamic-pituitary adrenal (HPA) axis to adjust physiology and behavior. Previous studies have detailed changes in baseline concentrations of the stress hormone corticosterone during a single storm event, but little data exists on how stress physiology and body condition are adjusted as the storm progresses across multiple days. This represents a serious gap in our understanding of how birds respond physiologically over the duration of a storm. We documented arctic snowstorms that occurred over five consecutive years that were endured by Lapland longspurs (Calcarius lapponicus; 2012-2016) and in three consecutive years by white-crowned sparrows (Zonotrichia leucophrys gambelii; 2014-2016). Data were collected on storm-free days, during snowstorms ranging in length from 1 to 3 days, and the day immediately following a snowstorm. The specific aims were to understand how stress physiology, measured at baseline and in response to restraint handling, and body condition changed over multiple days of the storm, and if these responses were consistent across years. Snowstorms did not affect baseline corticosterone concentrations for either species except for female Lapland longspurs and male white-crowned sparrows in 2014. Lapland longspurs, regardless of sex, increased stress-induced (restraint handling) corticosterone in response to snowstorms in all years but 2013, which was characterized by unusually harsh conditions. Both sexes of White-crowned sparrows showed a significant increase in the stress-induced levels of corticosterone during snowstorms in one of the three years of the study. Stress-induced corticosterone concentrations were only different across each day of the storm in one year of the study for Lapland longspurs. Changes in fat and body mass were not uniform across years, but measurable increases in fat stores and body mass were detected in males of both species during the first day of a snowstorm with declines typically occurring by the second day. Our study showed that severe weather events often caused rapid increases in HPA axis activity and body condition, but these profiles are likely dependent upon ecological and environmental context within the breeding season.


Assuntos
Cruzamento , Neve , Aves Canoras/fisiologia , Estresse Fisiológico , Adiposidade/fisiologia , Animais , Regiões Árticas , Peso Corporal , Corticosterona/sangue , Feminino , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Sistema Hipófise-Suprarrenal/fisiologia , Restrição Física , Aves Canoras/sangue
19.
Gen Comp Endocrinol ; 267: 82-89, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29908835

RESUMO

Early life experiences can affect the function of the hypothalamo-pituitary-adrenal (HPA) axis of vertebrates, with potential fitness consequences later in life. In altricial species, for example, variation in parental behavior, e.g. brooding or feeding, can modify the activity of the HPA axis of the young by altering their exposure to noxious stimuli as the young develop in the nest. We have shown that a drop in the body temperature of eastern bluebird (Sialia sialis) chicks, such as occurs when females are away from the nest, elevates their blood corticosterone levels. If repeated during the early days of their development, cooling bouts also reduce the chicks' later corticosterone secretion in response to handling. Thus, variation in maternal behavior has the capacity to shape the function of the chicks' HPA axis. To better understand how maternal absence from the nest activates the HPA axis of bluebird chicks, we experimentally mimicked the cooling that occurs when the female is away from the nest, and investigated a) the age at which the HPA axis becomes capable of responding to cooling by increasing corticosterone secretion, b) whether corticosterone secretion remains elevated throughout long periods of cooling, and c) whether fasting (also potentially associated with maternal absence) interacts with cooling to affect corticosterone secretion. Cooling for 18 min significantly elevated circulating corticosterone levels of chicks as young as 4 days post-hatch, indicating that their HPA axis is sensitive to cooling very early in life. Corticosterone levels remained elevated throughout longer bouts of cooling. However, a 1-hr period of fasting had no effect on corticosterone secretion, regardless of whether chicks were cooled or not. Collectively, these data demonstrate that variation in maternal brooding behavior can substantially modify the corticosterone profiles of chicks during early postnatal development, and that chick temperature is likely the main driver of this.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Temperatura Corporal/fisiologia , Sistema Hipotálamo-Hipofisário/fisiologia , Estado Nutricional , Sistema Hipófise-Suprarrenal/fisiologia , Aves Canoras/fisiologia , Envelhecimento/fisiologia , Animais , Temperatura Baixa , Corticosterona/sangue , Aves Canoras/sangue , Estresse Fisiológico/fisiologia , Fatores de Tempo
20.
Homo ; 69(1-2): 50-61, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29705502

RESUMO

Previous research proposes stress as a mechanism for linking social environments and biological bodies. In particular, non-human primate studies investigate relationships between cortisol as a measure of stress response and social hierarchies. Because human social structures often include hierarchies of dominance and social status, humans may exhibit similar patterns. Studies of non-human primates, however, have not reached consistent conclusions with respect to relationships between social position and levels of cortisol. While human studies report associations between cortisol and various aspects of social environments, studies that consider social status as a predictor of stress response also report mixed results. Others have argued that perceptions of social status may have different implications for stress response depending upon social context. We propose here that characteristics of children's social networks may be a better predictor of central tendencies and variability of stress response than their perceptions of social status. This is evaluated among 24 children from 9.4 to 11.3 years of age in one upper middle-class New Zealand primary school classroom, assessed through observation within the classroom, self-reports during semi-structured interviews and 221 serial saliva samples provided daily over 10 consecutive school days. A synthetic assessment of the children's networks and peer-relationships was developed prior to saliva-cortisol analysis. We found that greater stability of peer-relationships within groups significantly predicts lower within-group variation in mid-morning cortisol over the two-week period, but not overall within-group differences in mean cortisol.


Assuntos
Meio Social , Apoio Social , Estresse Fisiológico , Criança , Feminino , Humanos , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Nova Zelândia , Sistema Hipófise-Suprarrenal/fisiologia , Saliva/metabolismo , Estudantes
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