RESUMEN
Neuronal nitric oxide synthase (nNOS) has various roles as a neurotransmitter. However, studies to date have produced insufficient data to fully support the correlation between nNOS and bowel motility. This study aimed to investigate the correlation between nNOS expression and gastrointestinal (GI) tract motility using a stress-induced neonatal maternal separation (NMS) mouse model. In this study, we generated a genetically modified mouse with the HiBiT sequence knock-in into the nNOS gene using CRISPR/Cas9 for analyzing accurate nNOS expression. nNOS expression was measured in the stomach, small intestine, large intestine, adrenal gland, and hypothalamus tissues after establishing the NMS model. The NMS model exhibited a significant increase in nNOS expression in large intestine, adrenal gland, and hypothalamus. Moreover, a significant positive correlation was observed between whole gastrointestinal transit time and the expression level of nNOS. We reasoned that NMS induced chronic stress and consequent nNOS activation in the hypothalamic-pituitary-adrenal (HPA) axis, and led to an excessive increase in intestinal motility in the lower GI tract. These results demonstrated that HiBiT is a sensitive and valuable tool for analyzing in vivo gene activation, and nNOS could be a biomarker of the HPA axis-linked lower intestinal tract dysfunction.
Asunto(s)
Bioquímica/métodos , Motilidad Gastrointestinal , Óxido Nítrico Sintasa de Tipo I/metabolismo , Estrés Psicológico/enzimología , Estrés Psicológico/fisiopatología , Animales , Encéfalo/enzimología , Sistemas CRISPR-Cas/genética , Modelos Animales de Enfermedad , Tránsito Gastrointestinal , Sistema Hipotálamo-Hipofisario/enzimología , Sistema Hipotálamo-Hipofisario/fisiopatología , Intestino Grueso/enzimología , Privación Materna , Ratones Endogámicos C57BL , Óxido Nítrico/metabolismo , Oligodesoxirribonucleótidos/metabolismo , Sistema Hipófiso-Suprarrenal/enzimología , Sistema Hipófiso-Suprarrenal/fisiopatologíaRESUMEN
Life-course experiences have been postulated to program hypothalamus-pituitary-adrenal (HPA) axis activity, suggesting that HPA axis activity is, at least partially, stable over time. Yet, there is paucity of data on the long-term stability of cortisol production and metabolism. We performed a prospective follow-up study in twins recruited from a nationwide register to estimate the stability of cortisol production and metabolism over time, and the contribution of genetic and environmental factors to this stability. In total, 218 healthy mono- and dizygotic twins were included. At the ages of 9, 12 and 17 years, morning urine samples were collected for assessment (by gas chromatography-tandem mass spectrometry) of cortisol metabolites, enabling the calculation of cortisol metabolite excretion rate and cortisol metabolism activity. Our results showed a low stability for both cortisol metabolite excretion rate (with correlations <.20) and cortisol metabolism activity indices (with correlations of .25 to .46 between 9 and 12 years, -.02 to .15 between 12 and 17 years and .09 to .28 between 9 and 17 years). Because of the low stability over time, genetic and environmental contributions to this stability were difficult to assess, although it seemed to be mostly determined by genetic factors. The low stability in both cortisol production and metabolism between ages 9 and 17 years reflects the dynamic nature of the HPA axis.
Asunto(s)
Glucocorticoides/metabolismo , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisario/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/metabolismo , Adolescente , Niño , Cromatografía de Gases , Cortisona/metabolismo , Cortisona/orina , Citocromo P-450 CYP3A/metabolismo , Femenino , Estudios de Seguimiento , Interacción Gen-Ambiente , Estudios de Asociación Genética , Glucocorticoides/orina , Humanos , Hidrocortisona/orina , Sistema Hipotálamo-Hipofisario/enzimología , Estudios Longitudinales , Masculino , Sistema Hipófiso-Suprarrenal/enzimología , Estudios Prospectivos , Sistema de Registros , Espectrometría de Masas en Tándem , Gemelos Dicigóticos , Gemelos Monocigóticos/genéticaRESUMEN
Reported findings on reactivity to stress of the sympathetic-adreno-medullar (SAM) and hypothalamic-pituitary-adrenal (HPA) systems in panic disorder (PD) are very variable. This inconsistency may be explained by differences in treatment exposure, illness duration and emotion regulation strategies. The present study examined the reactivity to mental stress of the SAM and HPA axes in a sample of first episode, drug naïve patients with PD which avoids confounds of medications exposure and illness chronicity. Activation of the SAM axis was evaluated by dosage of salivary alpha-amylase (sAA) and heart rate. Activation of the HPA axis was tested by dosage of salivary cortisol. Psychological assessments were done by the Self-Rating Depression Scale, the Self-Rating Anxiety Scale, the State-Trait Anxiety Inventory, the Cope Orientation to Problems Experienced (COPE) Inventory and the 16 Personality Factor Questionnaire (16PF). Patients showed reduced sAA stress reactivity, higher baseline cortisol levels and a more rapid decrease in stress cortisol levels as compared with controls. A significant correlation was found between active coping strategies and cortisol levels (response to stress). The findings suggest that blunted SAM stress reactivity and a rapid decrease in stress cortisol levels reflect traits that may enhance vulnerability to psychopathology in patients with PD.
Asunto(s)
Hidrocortisona/metabolismo , Trastorno de Pánico/metabolismo , Trastorno de Pánico/fisiopatología , alfa-Amilasas Salivales/metabolismo , Estrés Psicológico/fisiopatología , Adaptación Psicológica/fisiología , Adolescente , Adulto , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Sistema Hipotálamo-Hipofisario/enzimología , Sistema Hipotálamo-Hipofisario/metabolismo , Masculino , Trastorno de Pánico/enzimología , Sistema Hipófiso-Suprarrenal/enzimología , Sistema Hipófiso-Suprarrenal/metabolismo , Escalas de Valoración Psiquiátrica , Saliva/enzimología , Estrés Psicológico/complicaciones , Adulto JovenRESUMEN
OBJECTIVE: Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis has been reported in depression. The aim was to investigate the potential association between depression and seven genes regulating or interfering with the HPA axis, including the gene encoding angiotensin converting enzyme (ACE). METHODS: In total, 78 single nucleotide polymorphisms (SNPs) and one insertion/deletion polymorphism were genotyped. The study included 408 individuals with depression and 289 controls. In a subset of cases, the interaction between genetic variants and stressful life events (SLEs) was investigated. RESULTS: After quality control, 68 genetic variants were left for analyses. Four of nine variants within ACE were nominally associated with depression and a gene-wise association was likewise observed. However, none of the SNPs located within AVP, CRH, CRHR1, CRHR2, FKBP5 or NC3C1 were associated with depression. One nominally significant interaction, most likely due to chance, was identified. CONCLUSION: The results indicate that ACE could be a potential candidate gene for depression.
Asunto(s)
Trastorno Depresivo/genética , Sistema Hipotálamo-Hipofisario/metabolismo , Peptidil-Dipeptidasa A/genética , Sistema Hipófiso-Suprarrenal/metabolismo , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Sistema Hipotálamo-Hipofisario/enzimología , Masculino , Sistema Hipófiso-Suprarrenal/enzimología , Polimorfismo de Nucleótido SimpleRESUMEN
The purpose of this study is to determine the effect of prolonged iodine overdose on type 2 iodothyronine deiodinase (D2) ubiquitination-related enzymes. Male Wistar rats were fed different doses of iodine and were then euthanized at the 4, 8, 12, or 24 weeks (4w, 8w, 12w, or 24w) after iodine administration. Urinary iodine concentration (UIC), thyroid-stimulating hormone (TSH), total thyroxine (TT4), and total triiodothyronine (TT3) were determined. Real-time quantitative RT-PCR and Western blot were used to measure mRNA and protein expression levels of pituitary D2 as well as two D2-specific ubiquitin ligases [WD repeat and SOCS box-containing protein 1 (WSB-1), membrane-associated ring finger (C3HC4) 6 (MARCH6 or TEB4)] and two D2-specific deubiquitinating enzymes [ubiquitin-specific peptidase 20 (USP20) and ubiquitin-specific peptidase 33 (USP33)]. The mRNA and protein expression levels of USP19, a TEB4-specific deubiquitinating enzyme, were also measured. Prolonged high iodine intake significantly increased TSH expression. At 12w, TSH was 1.57-, 1.44-, and 2.11-fold of NI group in 6HI, 10HI, and 50HI groups, respectively. At 24w, TSH had increased to 2.11-fold in the 50HI group. The pituitary D2 protein level decreased at 12w and 24w; though the mRNA level did not change. Prolonged iodine intake increased mRNA and protein expression levels of pituitary WSB-1 and TEB4. High iodine intake had no discernible effects on USP20. Temporary increases in USP33 and USP19 mRNA levels were observed. The enzymes related to D2 ubiquitination change with prolonged high iodine intake. Increased D2 ubiquitination suppresses the activity of D2, causing a decrease in negative feedback of the hypothalamic-pituitary-thyroid axis.
Asunto(s)
Sobredosis de Droga/enzimología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Sistema Hipotálamo-Hipofisario/enzimología , Yodo/efectos adversos , Hipófisis/enzimología , Sistema Hipófiso-Suprarrenal/enzimología , Ubiquitina Tiolesterasa/biosíntesis , Ubiquitina-Proteína Ligasas/biosíntesis , Animales , Yoduro Peroxidasa/metabolismo , Yodo/farmacología , Masculino , Ratas , Ratas Wistar , Yodotironina Deyodinasa Tipo IIRESUMEN
Sleep has been linked to the daily patterns of stress-responsive physiological systems, specifically the hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system (ANS). However, extant research examining sleep and diurnal patterns of cortisol, the primary end product of the HPA axis, has primarily focused on sleep duration with limited attention on other facets of sleep. For example, it is not clear how specific aspects of sleep (e.g., sleep quality, sleep duration variability) are related to specific components of diurnal cortisol rhythms. Salivary alpha-amylase (sAA) has been recognized as a surrogate marker of ANS activity, but limited research has explored relations between sleep and sAA diurnal rhythms. The current study utilized an ecological momentary assessment protocol to examine within- and between-person relations between several facets of sleep behavior using multiple methods (e.g., subjective report, actigraphy) and salivary cortisol and sAA. Older adolescents (N=76) provided saliva samples and diary entries five times per day over the course of three days. Sleep was assessed via questionnaire, through daily diaries, and monitored objectively using actigraphy over a four day period. Between-person results revealed that shorter average objective sleep duration and greater sleep duration variability were related to lower levels of waking cortisol and flatter diurnal slopes across the day. Within-person results revealed that on nights when individuals slept for shorter durations than usual they also had lower levels of waking cortisol the next day. Sleep was not related to the cortisol awakening response (CAR) or diurnal patterns of sAA, in either between-person or within-person analyses. However, typical sleep behaviors measured via questionnaire were related to waking levels of sAA. Overall, this study provides a greater understanding of how multiple components of sleep, measured in naturalistic environments, are related to cortisol and sAA diurnal rhythms, and how day-to-day, within-person changes in sleep duration contribute to daily variations in cortisol.
Asunto(s)
Ritmo Circadiano/fisiología , Hidrocortisona/metabolismo , alfa-Amilasas Salivales/metabolismo , Sueño/fisiología , alfa-Amilasas/metabolismo , Adolescente , Adulto , Sistema Nervioso Autónomo/enzimología , Sistema Nervioso Autónomo/metabolismo , Femenino , Humanos , Sistema Hipotálamo-Hipofisario/enzimología , Sistema Hipotálamo-Hipofisario/metabolismo , Masculino , Sistema Hipófiso-Suprarrenal/enzimología , Sistema Hipófiso-Suprarrenal/metabolismo , Saliva/enzimología , Saliva/metabolismo , Estrés Fisiológico/fisiología , Vigilia/fisiología , Adulto JovenRESUMEN
The influence of a single injection of haloperidol on basic carboxypeptidases (biologically active peptide processing enzymes) activity in rat tissues was studied. Acute exposure to haloperidol increased the activity of carboxypeptidases H (CP H) in hypothalamic-pituitary-adrenal system and cerebellum and reduced such activity in testes. Multidirectional changes of PMSF-inhibited carboxypeptidases activity (PMSF-CP) were observed after a single haloperidol injection in all studied tissues except testes. It is suggested that changes of CP H and PMSF-CP activity might affect levels of regulatory peptides in the brain and blood and thus may be involved in general and side effects of haloperidol on the organism.
Asunto(s)
Encéfalo/enzimología , Carboxipeptidasas/metabolismo , Haloperidol/farmacología , Testículo/enzimología , Animales , Encéfalo/efectos de los fármacos , Carboxipeptidasas/antagonistas & inhibidores , Haloperidol/administración & dosificación , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Sistema Hipotálamo-Hipofisario/enzimología , Inyecciones Intraperitoneales , Masculino , Especificidad de Órganos , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Sistema Hipófiso-Suprarrenal/enzimología , Inhibidores de Proteasas/farmacología , Ratas , Testículo/efectos de los fármacos , Compuestos de Tosilo/farmacologíaRESUMEN
Epigenetic modifications in response to traumatic experience and stress are emerging as important factors in the long-term biological trajectories leading to stress-related psychiatric disorders, reflecting both environmental influences as well as individual genetic predisposition. In particular, recent evidence on DNA methylation changes within distinct genes and pathways but also on a genome-wide level provides new insights into the pathophysiology of stress related psychiatric disorders. This review summarizes current findings and concepts on DNA methylation changes in stress-related disorders with a focus on major depressive disorder and posttraumatic stress disorder (PTSD). We highlight studies of DNA methylation in animals and humans pertinent to these disorders, both focusing on candidate loci as well as genome-wide studies. We describe molecular mechanisms of how exposure to stress can induce long lasting changes in DNA methylation and how these may relate to the pathophysiology of depression and PTSD. We discuss data suggesting that DNA methylation, even in peripheral tissues, appears to be an informative reflection of environmental exposures on the genome and may have potential as a biomarker for the early prevention of stress-related disorders.
Asunto(s)
Encéfalo/metabolismo , Metilación de ADN , Trastorno Depresivo Mayor/metabolismo , Epigénesis Genética , Interacción Gen-Ambiente , Neuronas/metabolismo , Trastornos por Estrés Postraumático/metabolismo , Animales , Encéfalo/enzimología , Trastorno Depresivo Mayor/etiología , Regulación de la Expresión Génica , Humanos , Sistema Hipotálamo-Hipofisario/enzimología , Sistema Hipotálamo-Hipofisario/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neuronas/enzimología , Nervios Periféricos/enzimología , Nervios Periféricos/metabolismo , Sistema Hipófiso-Suprarrenal/enzimología , Sistema Hipófiso-Suprarrenal/inervación , Sistema Hipófiso-Suprarrenal/metabolismo , Trastornos por Estrés Postraumático/enzimología , Estrés Fisiológico , Estrés Psicológico/psicologíaAsunto(s)
Hormona Adrenocorticotrópica/metabolismo , Proteínas CLOCK/metabolismo , Homeostasis , Sistema Hipotálamo-Hipofisario/enzimología , Sistema Hipófiso-Suprarrenal/enzimología , Estrés Fisiológico , Estrés Psicológico/enzimología , Animales , Humanos , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisario/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Estrés Psicológico/metabolismo , Estrés Psicológico/fisiopatologíaRESUMEN
Chronic subordinate colony (CSC) housing for 19 days results in unaffected basal morning corticosterone (CORT) levels despite a pronounced increase in adrenal mass, likely mediated by an attenuation of adrenal corticotropin (ACTH) responsiveness. Given that the pronounced increase in basal morning plasma CORT levels returns to baseline as early as 48âh after the start of CSC, it is likely that the attenuated ACTH responsiveness develops already during this initial phase. This was tested in the present study. In line with previous findings, basal morning plasma CORT levels were elevated following 10âh, but not 48âh, of CSC exposure. Basal morning plasma ACTH concentrations and relative in vivo adrenal CORT content were increased following 10âh and to a lesser extent following 48âh of CSC exposure, positively correlating. Relative in vitro adrenal CORT secretion in response to ACTH (100ânM) and kidney protein expression of 11ß-hydroxysteroid dehydrogenase type 2 (HSD11B2) were unaffected following both time points. Adrenal mRNA expression of key steroidogenic enzymes was unaffected/decreased following 10âh and unaffected/increased following 48âh of CSC exposure. Together, our findings suggest that basal plasma hypercorticism during the initial CSC phase is mainly prevented by an attenuation of pituitary ACTH release. An increased absolute adrenal weight following 10âh, but not 48âh, of CSC exposure indicates that restoration of normal adrenal mass also adds to a lesser extent to prevent basal hypercorticism. A contributing role of alterations in enzymatic CORT degradation and steroidogenic enzyme availability is likely, but has to be further addressed in future studies.
Asunto(s)
Sistema Hipotálamo-Hipofisario/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Estrés Psicológico , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2/genética , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2/metabolismo , Hormona Adrenocorticotrópica/metabolismo , Animales , Corticosterona/sangre , Humanos , Técnicas In Vitro , Riñón/enzimología , Masculino , Ratones , Ratones Endogámicos C57BL , Sistema Hipófiso-Suprarrenal/enzimologíaRESUMEN
The central and peripheral nervous systems are important factors influencing the functioning of liver cytochrome P450 (CYP). It has been shown that changes in the brain monoaminergic systems affect liver cytochrome P450 (CYP) expression (CYP1A, CYP2B, CYP2C11 and CYP3A). The brain dopaminergic system has been established as an important center regulating the liver CYP. This regulation proceeds via the tuberoinfundibular pathway and the dopaminergic D2 receptors of the pituitary, as well as the mesolimbic pathway engaging the D2 receptors of the nucleus accumbens (conveying a message to the paraventricular nucleus of the hypothalamus). These two dopaminergic pathways stimulate the secretion of pituitary hormones, which directly (GH) or indirectly (ACTH, TSH) activate hepatic nuclear/ cytosolic receptors controlling CYP genes. Recent preliminary studies with selective noradrenaline or serotonin neurotoxins suggest also involvement of the brain noradrenergic and serotonergic systems in the regulation of liver CYP. Moreover, the influence of the peripheral nervous system involving several neurotransmitters (acetylcholine, noradrenaline, adrenaline, dopamine, serotonin) on liver function may also be important for the physiological regulation of hepatic CYP activity. The hypothalamus controls liver function not only by releasing hormones from the pituitary gland but also by stimulating the autonomic sympathetic and parasympathetic projections to the liver. In addition to direct neural connections, the autonomic nervous system can indirectly affect liver function via the hypothalamus-adrenal axis and the hypothalamus- pancreas axis. Therefore, the estimation of neuroactive drug action on hepatic CYP requires an in vivo model which allows the central neuroendocrine and peripheral autonomic regulation of genes coding for CYP isoforms.
Asunto(s)
Sistema Nervioso Central/fisiología , Sistema Enzimático del Citocromo P-450/metabolismo , Hígado/enzimología , Sistema Nervioso Periférico/fisiología , Animales , Monoaminas Biogénicas/fisiología , Citocinas/metabolismo , Hormonas Esteroides Gonadales/fisiología , Hormona del Crecimiento/fisiología , Humanos , Sistema Hipotálamo-Hipofisario/enzimología , Hígado/efectos de los fármacos , Modelos Neurológicos , Hormonas Hipofisarias/metabolismo , Sistema Hipófiso-Suprarrenal/enzimología , Psicotrópicos/farmacología , Hormonas Tiroideas/fisiologíaRESUMEN
Inflammation-induced activation of the hypothalamic-pituitary-adrenal (HPA) axis has been suggested to depend on prostaglandins, but the prostaglandin species and the prostaglandin-synthesizing enzymes that are responsible have not been fully identified. Here, we examined HPA axis activation in mice after genetic deletion or pharmacological inhibition of prostaglandin E(2)-synthesizing enzymes, including cyclooxygenase-1 (Cox-1), Cox-2, and microsomal prostaglandin E synthase-1 (mPGES-1). After immune challenge by intraperitoneal injection of lipopolysaccharide, the rapid stress hormone responses were intact after Cox-2 inhibition and unaffected by mPGES-1 deletion, whereas unselective Cox inhibition blunted these responses, implying the involvement of Cox-1. However, mPGES-1-deficient mice showed attenuated transcriptional activation of corticotropin-releasing hormone (CRH) that was followed by attenuated plasma concentrations of adrenocorticotropic hormone and corticosterone. Cox-2 inhibition similarly blunted the delayed corticosterone response and further attenuated corticosterone release in mPGES-1 knock-out mice. The expression of the c-fos gene, an index of synaptic activation, was maintained in the paraventricular hypothalamic nucleus and its brainstem afferents both after unselective and Cox-2 selective inhibition as well as in Cox-1, Cox-2, and mPGES-1 knock-out mice. These findings point to a mechanism by which (1) neuronal afferent signaling via brainstem autonomic relay nuclei and downstream Cox-1-dependent prostaglandin release and (2) humoral, CRH transcription-dependent signaling through induced Cox-2 and mPGES-1 elicited PGE(2) synthesis, shown to occur in brain vascular cells, play distinct, but temporally supplementary roles for the stress hormone response to inflammation.
Asunto(s)
Dinoprostona/biosíntesis , Sistema Hipotálamo-Hipofisario/enzimología , Sistema Hipotálamo-Hipofisario/inmunología , Sistema Hipófiso-Suprarrenal/enzimología , Sistema Hipófiso-Suprarrenal/inmunología , Hormona Adrenocorticotrópica/antagonistas & inhibidores , Hormona Adrenocorticotrópica/metabolismo , Animales , Corticosterona/antagonistas & inhibidores , Corticosterona/metabolismo , Ciclooxigenasa 2/biosíntesis , Ciclooxigenasa 2/metabolismo , Inhibidores de la Ciclooxigenasa 2/administración & dosificación , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Oxidorreductasas Intramoleculares/antagonistas & inhibidores , Oxidorreductasas Intramoleculares/biosíntesis , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Noqueados , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Prostaglandina-E SintasasRESUMEN
A classical view of the neuroendocrine-immune network assumes bidirectional interactions where pro-inflammatory cytokines influence hypothalamic-pituitary-adrenal (HPA) axis-derived hormones that subsequently affect cytokines in a permanently servo-controlled circle. Nevertheless, this picture has been continuously evolving over the last years as a result of the discovery of redundant expression and extended functions of many of the molecules implicated. Thus, cytokines are not only expressed in cells of the immune system but also in the central nervous system, and many hormones present at hypothalamic-pituitary level are also functionally expressed in the brain as well as in other peripheral organs, including immune cells. Because of this intermingled network of molecules redundantly expressed, the elucidation of the unique roles of HPA axis-related molecules at every level of complexity is one of the major challenges in the field. Genetic engineering in the mouse offers the most convincing method for dissecting in vivo the specific roles of distinct molecules acting in complex networks. Thus, various immunological, behavioral, and signal transduction studies performed with different HPA axis-related mutant mouse lines to delineate the roles of beta-endorphin, the type 1 receptor of corticotropin-releasing hormone (CRHR1), and its ligand CRH will be discussed here.
Asunto(s)
Conducta/fisiología , Sistema Hipotálamo-Hipofisario/inmunología , Sistema Hipófiso-Suprarrenal/inmunología , Transducción de Señal , Animales , Sistema Hipotálamo-Hipofisario/enzimología , Ratones , Ratones Transgénicos , Especificidad de Órganos , Sistema Hipófiso-Suprarrenal/enzimologíaRESUMEN
Patients with congenital adrenal hyperplasia arising from mutations of 11beta-hydroxylase, the final enzyme in the glucocorticoid biosynthetic pathway, exhibit glucocorticoid deficiency, adrenal hyperplasia driven by unsuppressed hypothalamo-pituitary-adrenal activity, and excess mineralocorticoid activity caused by the accumulation of deoxycorticosterone. A mouse model, in which exons 3-7 of Cyp11b1 (the gene encoding 11beta-hydroxylase) were replaced with cDNA encoding enhanced cyan fluorescent protein, was generated to investigate the underlying disease mechanisms. Enhanced cyan fluorescent protein was expressed appropriately in the zona fasciculata of the adrenal gland, and targeted knock-out was confirmed by urinary steroid profiles and, immunocytochemically, by the absence of 11beta-hydroxylase. The null mice exhibited glucocorticoid deficiency, mineralocorticoid excess, adrenal hyperplasia, mild hypertension, and hypokalemia. They also displayed glucose intolerance. Because rodents do not synthesize adrenal androgens, changes in reproductive function such as genital virilization of females were not anticipated. However, adult homozygote females were infertile, their ovaries showing an absence of corpora lutea and a central proliferation of disorganized steroidogenic tissue. Null females responded normally to superovulation, suggesting that raised systemic progesterone levels also contribute to infertility problems. The model reveals previously unrecognized phenotypic subtleties of congenital adrenal hyperplasia.
Asunto(s)
Glándulas Suprarrenales/enzimología , Hiperplasia Suprarrenal Congénita/enzimología , Modelos Animales de Enfermedad , Sistema Hipotálamo-Hipofisario/enzimología , Sistema Hipófiso-Suprarrenal/enzimología , Esteroide 11-beta-Hidroxilasa , Glándulas Suprarrenales/patología , Hiperplasia Suprarrenal Congénita/genética , Hiperplasia Suprarrenal Congénita/patología , Animales , Cuerpo Lúteo/enzimología , Cuerpo Lúteo/patología , Exones , Femenino , Glucocorticoides/deficiencia , Intolerancia a la Glucosa/enzimología , Intolerancia a la Glucosa/genética , Intolerancia a la Glucosa/patología , Heterocigoto , Homocigoto , Humanos , Sistema Hipotálamo-Hipofisario/patología , Infertilidad Femenina/enzimología , Infertilidad Femenina/genética , Infertilidad Femenina/patología , Masculino , Ratones , Ratones Noqueados , Mineralocorticoides/sangre , Sistema Hipófiso-Suprarrenal/patología , Esteroide 11-beta-Hidroxilasa/genéticaRESUMEN
Maternal undernutrition leads to intrauterine growth retardation and predisposes to the development of pathologies in adulthood. The hypothalamo-pituitary-adrenal axis is a major target of early-life programming. We showed previously that perinatal maternal 50% food restriction leads to hypothalamo-pituitary-adrenal axis hyperactivity and disturbs glucocorticoid feedback in adult male rats. To try to better understand these alterations, we studied several factors involved in corticosterone sensitivity. We showed that unlike the restricted expression of 11 beta-HSD2 mRNA, the 11 beta-HSD1, glucocorticoid, and mineralocorticoid receptor genes are widely distributed in rat. In contrast to the hypothalamus, we confirmed that maternal undernutrition modulates hippocampal corticosterone receptor balance and leads to increased 11 beta-HSD1 gene expression. In the pituitary, rats exhibited a huge increase in both mRNA and mineralocorticoid receptor binding capacities as well as decreased 11 beta-HSD1/11 beta-HSD2 gene expression. Using IN SITU hybridization, we showed that the mineralocorticoid receptor gene was expressed in rat corticotroph cells and by other adenopituitary cells. In the adrenal gland, maternal food restriction decreased 11beta-HSD2 mRNA. This study demonstrated that maternal food restriction has both long-term and tissue-specific effects on gene expression of factors involved in glucocorticoid sensitivity and that it could contribute, via glucocorticoid excess, to the development of adult diseases.
Asunto(s)
11-beta-Hidroxiesteroide Deshidrogenasas/biosíntesis , Animales Recién Nacidos/metabolismo , Sistema Hipotálamo-Hipofisario/metabolismo , Desnutrición/metabolismo , Receptores de Glucocorticoides/biosíntesis , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/biosíntesis , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/genética , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2/biosíntesis , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2/genética , Animales , Sistema Hipotálamo-Hipofisario/anatomía & histología , Sistema Hipotálamo-Hipofisario/enzimología , Hibridación in Situ , Masculino , Sistema Hipófiso-Suprarrenal/anatomía & histología , Sistema Hipófiso-Suprarrenal/enzimología , Sistema Hipófiso-Suprarrenal/metabolismo , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Ratas , Ratas Wistar , Receptores de Mineralocorticoides/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Nitric oxide (NO) is a free radical gas synthesised from arginine and oxygen by enzymes of the family of the nitric oxide synthase. In particular, the neuronal nitric oxide synthase (nNOS) is highly expressed by cells of the hypothalamic paraventricular nucleus, where the sympatho-adrenal system, the hypothalamic-pituitary-adrenal axis and the hypothalamic-neurohypophyseal system originate. These structures are deputed to regulate the neuroendocrine stress response. In the past years, evidence has been accumulated to suggest that NO of nNOS origin plays a significant role in modulating the activity of the above mentioned systems under acute stressor exposure. The availability of nNOS knock-out mice allowed to investigate not only the physiological consequences of a constitutive lack of NO of nNOS origin at the hormonal and molecular level, but also to examine possible behavioural alterations. In this review, we shall discuss and confront the current trends of research in this area, especially focusing on the latest findings gained from genetically modified mice.
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Regulación Enzimológica de la Expresión Génica , Sistema Hipotálamo-Hipofisario/enzimología , Óxido Nítrico Sintasa de Tipo I/metabolismo , Núcleo Hipotalámico Paraventricular/enzimología , Sistema Hipófiso-Suprarrenal/enzimología , Estrés Fisiológico/enzimología , Animales , Conducta Animal , Regulación Enzimológica de la Expresión Génica/genética , Ratones , Ratones Noqueados , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa de Tipo I/genética , Estrés Fisiológico/genéticaRESUMEN
Metabolic dysregulation is associated with reproductive disorders, but the underlying mechanisms are not clearly understood. Adiponectin is an adipocyte-derived secretory factor that improves insulin sensitivity. Results from animal models indicate that overexpression of adiponectin impairs female fertility. We hypothesized that adiponectin regulates reproduction by altering the hypothalamic-pituitary axis. Mouse LbetaT2 immortalized gonadotrope cells express both adiponectin receptors 1 and 2. Adiponectin increases phosphorylation of AMP-activated protein kinase (AMPK), a downstream target of adiponectin receptors, and reduces basal and GnRH-stimulated LH secretion, acutely. The repression of LH secretion can be mimicked by 5-aminoimidazole-4-carboxamide-1-beta-riboside, an AMP analog, suggesting the involvement of AMPK. A dominant-negative AMPK mutant or compound C, a selective AMPK inhibitor, potentiates basal LH secretion and abolishes the inhibitory effect of adiponectin. Chronic activation of AMPK by 5-aminoimidazole-4-carboxamide-1-beta-riboside decreases cellular LH levels, and expression of dominant-negative AMPK increases cellular LH levels, suggesting a second effect of AMPK to regulate LH synthesis. Lastly, intravenous injection of an adenovirus expressing adiponectin into male mice reduces serum LH levels without changing FSH levels. In conclusion, our results suggest that adiponectin decreases LH secretion in pituitary gonadotropes in an AMPK-dependent manner.
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Adenilato Quinasa/metabolismo , Regulación Enzimológica de la Expresión Génica/fisiología , Gonadotrofos/efectos de los fármacos , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Hormona Luteinizante/metabolismo , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Adiponectina/farmacología , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacología , Animales , Línea Celular , Activación Enzimática/efectos de los fármacos , Gonadotrofos/metabolismo , Hipoglucemiantes/farmacología , Sistema Hipotálamo-Hipofisario/enzimología , Sistema Hipotálamo-Hipofisario/metabolismo , Hormona Luteinizante/antagonistas & inhibidores , Hormona Luteinizante/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Sistema Hipófiso-Suprarrenal/enzimología , Sistema Hipófiso-Suprarrenal/metabolismo , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Receptores de Adiponectina/biosíntesis , Receptores de Adiponectina/genética , Proteínas Recombinantes/farmacología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ribonucleótidos/farmacologíaRESUMEN
BACKGROUND: Aldosterone is important in the development of hypertension. We have shown that a single nucleotide polymorphism (SNP) (-344T) in the 5' regulatory region (UTR) of the gene encoding aldosterone synthase (CYP11B2) associates with aldosterone excess and hypertension as well as altered adrenal 11-hydroxylation efficiency (deoxycortisol to cortisol). This conversion is carried out by the enzyme 11beta-hydroxylase, encoded by the adjacent gene, CYP11B1. We proposed that the effects of CYP11B2 are explained by linkage disequilibrium (LD) across the CYP11B locus. We have demonstrated high LD across this locus and identified two SNPs in the 5' UTR of CYP11B1 (-1859 G/T, -1889 A/G) that associate with reduced transcription in vitro and altered 11-hydroxylation efficiency in vivo. Accordingly, we hypothesized that the reduced adrenal 11-hydroxylation may lead to chronic resetting of the pituitary-adrenal axis, with chronically increased ACTH drive resulting in aldosterone excess. METHODS: To test this, we examined hypothalamic-pituitary-adrenal (HPA) axis activity in hypertensive and normotensive individuals stratified according to genotype at CYP11B2 (-344T/C) and CYP11B1 (-1859 G/T, -1889 A/G). Fifty-six subjects homozygous for CYP11B2 SNP (27 TT, 12 CC), and 38 homozygous for CYP11B1 SNPs (18 TTGG, 20 GGAA) were recruited. Diurnal variation and the effects of dexamethasone suppression and ACTH stimulation on plasma aldosterone, cortisol and ACTH under controlled conditions were studied. RESULTS: Subjects with SNPs associated with reduced 11-hydroxylation efficiency (-344T CYP11B2; TTGG CYP11B1) showed reduced inhibition of ACTH after dexamethasone (P = 0.05) and an altered cortisol-ACTH relationship (decreased cortisol-ACTH ratio, P < 0.02). The same individuals also demonstrated close correlations between plasma cortisol and aldosterone (-344T CYP11B2 r = 0.508, P < 0.004; TTGG CYP11B1 r = 0.563, P < 0.003) suggesting that there was common regulation (possibly ACTH) of these hormones in genetically susceptible subjects. CONCLUSIONS: Variation in CYP11B2 and CYP11B1 associates with chronic up-regulation of the HPA axis. These novel data support the suggestion that chronic aldosterone excess, in genetically susceptible individuals, may be a consequence of increased ACTH drive to the adrenal and identify novel molecular mechanisms that may lead to the development of hypertension within the general population.
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Regulación Enzimológica de la Expresión Génica/genética , Hipertensión/enzimología , Hipertensión/genética , Sistema Hipotálamo-Hipofisario/enzimología , Sistema Hipófiso-Suprarrenal/enzimología , Adulto , Estudios de Casos y Controles , Citocromo P-450 CYP11B2/biosíntesis , Femenino , Variación Genética , Humanos , Masculino , Fenotipo , Esteroide 11-beta-Hidroxilasa/biosíntesis , Regulación hacia ArribaRESUMEN
Tryptophan hydroxylase-2 (TPH2) is a newly identified second form of TPH responsible for serotonin synthesis in the brain and has been increasingly implicated as a contributor to the etiology of various psychiatric disorders. In this study, we have identified the constellation of polymorphisms in rhesus monkey TPH2 and investigated genotype/phenotype association as well as gene expression effects of specific polymorphisms. Genomic DNA was obtained from 247 rhesus monkeys, among which 24 had been previously examined for plasma cortisol level, dexamethasone suppression, and combined dexmethasone/ACTH challenge. Polymorphisms in all exons, splicing junctions and approximately 2 kb of the 5'-flanking region (5'-FR) of TPH2 were identified by sequencing. We identified 17 single nucleotide polymorphisms (SNPs) including two that are predictive of amino-acid change (25Pro>His and 75Gly>Ser, respectively), two mononucleotide repeats, one dinucleotide repeat, and one 159-bp insertion polymorphism. The 3'-UTR polymorphisms were significantly associated with hypothalamic-pituitary-adrenal (HPA) axis activity, especially 2051A>C, which was strikingly correlated with plasma cortisol level in the morning only (F=10.203, P=0.001). Luciferase reporter gene assays showed that the 3'-UTR polymorphisms and haplotypes had a profound effect on in vitro gene expression. Accordingly, these investigations revealed that polymorphisms in 3'-UTR of rhesus monkey TPH2 modulate HPA axis function, presumably by affecting levels of TPH2 expression.
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Sistema Hipotálamo-Hipofisario/enzimología , Macaca mulatta/genética , Sistema Hipófiso-Suprarrenal/enzimología , Polimorfismo Genético/genética , Triptófano Hidroxilasa/genética , Regiones no Traducidas 3'/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Células Cultivadas , Ritmo Circadiano/genética , Ritmo Circadiano/fisiología , ADN/análisis , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Hidrocortisona/sangre , Desequilibrio de Ligamiento , Macaca mulatta/sangre , Masculino , Datos de Secuencia Molecular , Fenotipo , Homología de Secuencia de Ácido Nucleico , Triptófano Hidroxilasa/metabolismoRESUMEN
Effects of dams stress on the carboxypeptidase H: the neuropeptide exchange enzyme in the hypothalamo-pituitary-adrenall-gonadal system, was studied in the litter of different age (0, 14, 28, 45, and 120 day after birth) was studied. The sex differences in dynamic of enzyme activity in intact animals are substantiated. The effect of prenatal stress on carboxypeptidase H activity dependes on age and sex of animals. Prenatal stress is altering during the age dynamics of enzyme activity. This in the pituitary gland and hypothalamus of prenatal stressed female rats was a control for the male rats. In the adrenal and gonadal gland of prenatal stressed males, this was a control for the female rats female. The role of carboxypeptidase H in pubescence and mechanisms of effect of prenatal stress on sex system functional are discussed.