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1.
Life Sci ; 245: 117337, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31972205

RESUMO

BACKGROUND: Higher levels of glucocorticoids (GCs), and impaired regulation of the hypothalamic-pituitary-adrenal (HPA) axis may cause or exacerbate the occurrence of metabolic and psychiatric disorders. It has been reported that ginseng saponin extract (GSE) has an inhibitory effect on the hyperactivity of the HPA axis induced by stresses and increased corticosterone level induced by intraperitoneal injection of adrenocorticotrophic hormone (ACTH) in mice. However, the molecular mechanisms by which GSE and its active ginsenosides inhibit corticosterone secretion remain elusive. MAIN METHODS: Y1 mouse adrenocortical cells were treated with ACTH for up to 60 min to establish a cell model of corticosterone secretion. After treatment with different concentrations of GSE or ginsenoside monomers for 24 h prior to the addition of ACTH, analyses of cAMP content, PKA activity, and the levels of steroidogenesis regulators, melanocortin-2 receptor (MC2R), and melanocortin-2 receptor accessory protein (MRAP) in ACTH-induced Y1 cells were performed. RESULTS: We demonstrated that GSE inhibits ACTH-stimulated corticosterone production in Y1 cells by inhibiting factors critical for steroid synthesis. Ginsenoside Rd, an active ingredient of GSE, inhibits corticosterone secretion in the cells and impedes ACTH-induced corticosterone biosynthesis through down-regulation of proteins in the cAMP/PKA/CREB signaling pathway. In addition, Western blot and qPCR analyses showed that ginsenoside Rd attenuated the induction of MC2R and MRAP by ACTH. CONCLUSION: Our findings indicate that ginsenoside Rd inhibits ACTH-induced corticosterone production through blockading the MC2R-cAMP/PKA/CREB pathway in adrenocortical cells. Overall, this mechanism may represent an important therapeutic option for the treatment of stress-related disorders, further supporting the pharmacological benefits of ginseng.


Assuntos
Córtex Suprarrenal/efeitos dos fármacos , Hormônio Adrenocorticotrópico/farmacologia , Proteína de Ligação a CREB/metabolismo , Corticosterona/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Ginsenosídeos/farmacologia , Receptor Tipo 2 de Melanocortina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Córtex Suprarrenal/citologia , Córtex Suprarrenal/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Camundongos , Pregnenolona/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
2.
Bull Exp Biol Med ; 168(2): 250-253, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31776957

RESUMO

We studied the effect of chronic intranasal and peroral administration of a new peptide preparation AСTH15-18PGP in a dose of 100 mg/kg body weight on the state of vascular-platelet and plasma hemostasis in animals. It was found that this synthetic regulatory peptide administered intranasally can produce antiplatelet, anticoagulant, and antifibrin-stabilizing effects on the blood plasma in healthy rats. In both administration routes, the peptide induced activation of the anticoagulation system of the hemostasis by increasing enzymatic and non-enzymatic fibrinolysis; after intranasal administration, the fibrinolytic effects were more pronounced.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Anticoagulantes/farmacologia , Fibrinólise/efeitos dos fármacos , Hemostasia/efeitos dos fármacos , Oligopeptídeos/farmacologia , Inibidores da Agregação de Plaquetas/farmacologia , Prolina/análogos & derivados , Hormônio Adrenocorticotrópico/análogos & derivados , Animais , Coagulação Sanguínea/efeitos dos fármacos , Plaquetas/efeitos dos fármacos , Masculino , Prolina/farmacologia , Ratos , Ratos Wistar
3.
J Physiol Pharmacol ; 70(4)2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31642814

RESUMO

Early weaning of ewe lambs strongly stimulates the hypothalamic-pituitary-adrenal axis and is associated with suppressed growth rate despite the increased food intake. At the same time, plasma leptin concentration increases only slightly or undetectably. To better understand this atypical interdependence among somatic stress, leptin, and lamb growth rate, we analyzed impact of leptin and/or adrenocorticotropic hormone (ACTH) on growth hormone (GH) secretion as well as the effect of ACTH on mRNA expression of two splice variants of leptin receptor (LEPRa, LEPRb) in pituitary cells isolated from early weaned ewe lambs. The GH secretion under the influence of leptin and/or ACTH depended on the timing of exposure and hormone concentration. After 6 - 30 h, GH secretion increased under 10-11 - 10-8 M leptin (P ≤ 0.05). However, after 24 - 30 h, GH secretion significantly increased only in cells exposed to both leptin and ACTH compared to culture with leptin only. Simultaneously, there was a significant (P ≤ 0.05) decrease in leptin receptor mRNA expression under the influence of ACTH at 10-8 - 10-6 M after 12 - 30 and 24 - 30 h for LEPRa and LEPRb, respectively. ACTH-related downregulation of LEPR mRNA was associated with a significant (P ≤ 0.05) reduction in leptin-stimulated GH secretion, also after 24 - 30 hours. Thus, the timing of ACTH exposure, followed by decreased leptin receptor mRNA, converged with the timing of decreased GH secretion under the influence of leptin with ACTH. The ACTH-induced downregulation of LEPR mRNA therefore may underlie the decrease in GH. These results show a direct role for leptin, ACTH, and leptin receptor expression in modulation of pituitary GH secretion in early weaned ewe lambs. During the early weaning-induced stress response, the ACTH-mediated decrease in sensitivity of pituitary cells to leptin may abolish a stimulatory effect of leptin on GH secretion and explain in part, the reduction in lamb growth rate.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Hormônio do Crescimento/metabolismo , Leptina/farmacologia , Receptores para Leptina/genética , Animais , Feminino , Hipófise/citologia , Hipófise/metabolismo , RNA Mensageiro/metabolismo , Ovinos , Desmame
4.
Eur J Endocrinol ; 181(6): 639-645, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31614334

RESUMO

Objectives: Injectable tetracosactide hexa-acetate, ACTH 1-24 (Synacthen), is not marketed in many countries including India, whereas Injectable long acting porcine sequence, ACTH 1-39 (Acton Prolongatum®) is easily available and much cheaper. This study aimed to find the diagnostic accuracy of ACTH stimulation test using i.m. Acton Prolongatum® (acton prolongatum stimulation test, APST) in comparison with Synacthen (short synacthen test, SST) for the diagnosis of glucocorticoid insufficiency. Methods: Subjects with a suspicion of adrenal insufficiency based on clinical features underwent a SST with 250 µg Synacthen followed by APST using 30 units of Acton Prolongatum®. Serum cortisol levels were measured at 60 and 120 min following injection of Acton Prolongatum®. Stimulated peak cortisol of less than 18 µg/dL on SST was considered as adrenal insufficiency. Results: Forty seven patients with mean age of 36.7 ± 14.4 years were enrolled for the study. Based on SST, twenty (n = 20) persons were classified as having adrenal insufficiency, whereas twenty-seven (n = 27) were found to be normal. Area under the curve of APST (at 120 min) was 0.986 when compared to SST, thus proving its high accuracy. A serum cortisol cut off value of 19.5 µg/dL at 120-min following stimulation with Acton Prolongatum® showed a sensitivity of 100% and specificity of 88%. Conclusion: ACTH stimulation test using Acton Prolongatum® is an economical and accurate alternative to the short Synacthen test.


Assuntos
Insuficiência Adrenal/diagnóstico , Hormônio Adrenocorticotrópico/farmacologia , Insuficiência Adrenal/sangue , Adulto , Cosintropina/farmacologia , Humanos , Hidrocortisona/sangue , Pessoa de Meia-Idade , Adulto Jovem
5.
J Toxicol Sci ; 44(9): 601-610, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474741

RESUMO

To verify simultaneous measurement of blood levels of adrenal steroids as a tool to evaluate drug effects on adrenal steroidogenesis, dose- and time-dependent changes in blood levels of corticosterone and its precursors (pregnenolone, progesterone and deoxycorticosterone), as well as their relationship with the pathological changes in the adrenal gland, were examined in rats dosed with ketoconazole (KET). Also examined were whether effects on adrenal steroidogenesis that were not obvious in the blood steroid levels after sole administration of KET could be revealed by post-administration of ACTH, and the correlation between the blood and adrenal steroid levels. Male rats were dosed with 15, 50, or 150 mg/kg of KET for 1 or 7 days with or without ACTH, and the blood and adrenal concentrations of the steroids were measured. KET increased the blood deoxycorticosterone level even at a dose level and time point at which histopathological changes were not obvious. KET-induced changes in blood levels of other steroids were revealed by ACTH, and the blood and adrenal levels were generally correlated especially after ACTH post-administration. Thus, blood levels of adrenal steroids, including precursors, can be a sensitive and early marker of drug effects on the adrenal steroidogenesis that reflect adrenal levels of steroids. The usefulness of the multiple steroid measurement as a method for mechanism investigation of drug effects on the adrenal gland can be further enhanced by ACTH.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/metabolismo , Hormônio Adrenocorticotrópico/farmacologia , Desoxicorticosterona/sangue , Desoxicorticosterona/metabolismo , Cetoconazol/toxicidade , Pregnenolona/sangue , Pregnenolona/metabolismo , Progesterona/sangue , Progesterona/metabolismo , Glândulas Suprarrenais/patologia , Hormônio Adrenocorticotrópico/administração & dosagem , Animais , Cromatografia Líquida , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Fatores de Tempo
6.
Pharmacol Biochem Behav ; 186: 172767, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31491434

RESUMO

Approximately one third of patients with depression remain treatment resistant with existing antidepressants, suggesting that the currently-available antidepressants cannot induce appropriate responses in the brains of all patients. Long-term exposure to adrenocorticotrophic hormone (ACTH) has been proposed as a model that mimics at least some aspects of clinical treatment-resistant depression in rodents. The purpose of this study was to explore potential causes of antidepressant treatment resistance using the chronic ACTH-treated mouse model. We subjected ACTH-treated mice to a rodent model of electroconvulsive therapy, i.e., electroconvulsive seizure (ECS), which induces various molecular and cellular changes, including in gene expression and adult neurogenesis in the hippocampus. First, behavioral effect of repeated ECS in the forced swim test (FST) was examined. In our experimental setting, ACTH-treated mice showed resistance to the antidepressant-like effect of ECS in the FST. We then examined which cellular and molecular changes induced by ECS were attenuated by ACTH administration. Chronic ACTH treatment suppressed the increase of gene expression such as of Bdnf, Npy, and Drd1 induced by ECS in the hippocampus. In contrast, there was no difference in ECS-induced promotion of the early neurogenetic process in the hippocampus between ACTH-treated and control mice. Our results suggest the possibility that impaired neuromodulation and monoamine signaling in the hippocampus are among the factors contributing to antidepressant treatment resistance.


Assuntos
Hormônio Adrenocorticotrópico/administração & dosagem , Eletroconvulsoterapia , Hormônio Adrenocorticotrópico/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/genética , Masculino , Camundongos , Modelos Biológicos , Neurogênese , Neuropeptídeo Y/genética , RNA Mensageiro/metabolismo , Receptores de Dopamina D1/genética
7.
Int J Mol Sci ; 20(17)2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31454910

RESUMO

The interaction between the pituitary hormone, adrenocorticotropin (ACTH), and melanocortin-2 receptor (MC2R) orthologs involves the H6 F7 R8 W9 and R/K15 K16 R17 R18 motifs in ACTH making contact with corresponding contact sites on MC2R. Earlier studies have localized the common HFRW binding site of all melanocortin receptors to residues in TM2, TM3, and TM6 that are located close to the extracellular space. The current study has identified residues in Xenopus tropicalis (xt) MC2R in TM4 (I158, F161), in EC2 (M166), and in TM5 (V172) that also are involved in activation of xtMC2R, and may be in the R/KKRR contact site of xtMC2R. These results are compared to earlier studies on the corresponding domains of human MC2R and rainbow trout MC2R in an effort to identify common features in the activation of teleost and tetrapod MC2R orthologs following stimulation with ACTH.


Assuntos
Receptor Tipo 2 de Melanocortina/metabolismo , Xenopus/metabolismo , Hormônio Adrenocorticotrópico/farmacologia , Sequência de Aminoácidos , Animais , Células CHO , Membrana Celular/metabolismo , Cricetulus , Humanos , Mutação , Receptor Tipo 2 de Melanocortina/agonistas , Receptor Tipo 2 de Melanocortina/química , Receptor Tipo 2 de Melanocortina/genética , Xenopus/genética
8.
J Vet Intern Med ; 33(5): 2235-2238, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31448839

RESUMO

A 11-year-old male neutered Shih Tzu was referred to a tertiary facility with a history of weight loss, decreased appetite, polydipsia, and lethargy. The dog had a 10-year history of nonspecific allergic dermatitis and was being treated with 16 mg/kg of ketoconazole q12h for Malassezia dermatitis. Vague gastrointestinal signs, hypocholesterolemia, and lack of a stress leukogram increased suspicion for hypoadrenocorticism (HA). An adrenocorticotropic hormone (ACTH) stimulation test identified hypocortisolemia on pre- and post-ACTH samples and ketoconazole was discontinued. After a short course of corticosteroid treatment, an ACTH stimulation test was repeated and pre-ACTH cortisol concentration was within the reference range, and the post-ACTH cortisol concentration was mildly increased. The temporal association between return of adequate adrenocortical cortisol production and discontinuation of ketoconazole led to the conclusion that the dog had developed iatrogenic HA secondary to ketoconazole treatment.


Assuntos
Insuficiência Adrenal/veterinária , Doenças do Cão/induzido quimicamente , Doença Iatrogênica/veterinária , Cetoconazol/efeitos adversos , Insuficiência Adrenal/induzido quimicamente , Insuficiência Adrenal/diagnóstico , Hormônio Adrenocorticotrópico/administração & dosagem , Hormônio Adrenocorticotrópico/farmacologia , Animais , Antifúngicos/administração & dosagem , Antifúngicos/efeitos adversos , Antifúngicos/uso terapêutico , Dermatomicoses/tratamento farmacológico , Dermatomicoses/veterinária , Doenças do Cão/diagnóstico , Cães , Hidrocortisona/sangue , Cetoconazol/administração & dosagem , Cetoconazol/uso terapêutico , Malassezia , Masculino
9.
Gen Comp Endocrinol ; 282: 113215, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31276671

RESUMO

RT-PCR analysis of gar pituitary and brain indicated that different combinations of gar melanocortin receptor mRNAs are present in the same tissues with mRNAs for gar mrap1 and gar mrap2. Against this background, an objective of this study was to determine whether the ligand sensitivity for either ACTH or α-MSH was affected when gar (g) melanocortin receptors (Mcrs) were co-expressed with either of the accessory proteins gMrap1 or gMrap2 in Chinese Hamster Ovary cells. The results indicated that gMc2r has an obligatory requirement for co-expression with gMrap1 in order for the receptor to be activated by hACTH(1-24). In addition, activation of gMc2r did not occur when the receptor was expressed alone or co-expressed with gMrap2. Furthermore, co-expression of gMc2r with gMrap1 followed by stimulation with NDP-MSH resulted in a low level of activation (only at 10-7 M and 10-6 M). However, gMc1r, gMc3r, gMc4r, and gMc5r responded to stimulation by NDP-MSH in a more robust manner. Co-expression of gMc1r, gMc3r, gMc4r, and gMc5r with gMRAP1 had no effect on sensitivity to stimulation by NDP-MSH or hACTH(1-24). Co-expression with gMRAP2 had no negative or positive effect on ligand sensitivity for gMc1r, gMc3r, and gMc5r, however this treatment did increase the activation of CHO cells transfected with gMc4r following stimulation with both hACTH(1-24) (p < 0.001), and NDP-MSH (p < 0.001). Co-expression of gMC5R with either gMRAP1 or gMRAP2 increased trafficking of gMC5R to the plasma membrane. These pharmacological observations are compared to the response of melanocortin receptors from other neopterygian fishes, cartilaginous fishes, and tetrapods to stimulation by ACTH(1-24) and forms of α-MSH.


Assuntos
Peixes/metabolismo , Receptores de Melanocortina/metabolismo , Transdução de Sinais , Hormônio Adrenocorticotrópico/farmacologia , Sequência de Aminoácidos , Animais , Células CHO , Cricetinae , Cricetulus , AMP Cíclico/metabolismo , Peixes/genética , Regulação da Expressão Gênica , Genes Reporter , Humanos , Ligantes , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Melanocortina/química , Receptores de Melanocortina/genética
10.
Endocrinology ; 160(7): 1719-1730, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31166572

RESUMO

The control of steroidogenesis in the neonatal adrenal gland is of great clinical interest. We have previously demonstrated that the postnatal day (PD) 2 rat exhibits a large plasma corticosterone response to hypoxia in the absence of an increase in plasma ACTH measured by RIA, whereas the corticosterone response to exogenous ACTH is intact. By PD8, the corticosterone response to hypoxia is clearly ACTH-dependent. We hypothesized that this apparently ACTH-independent response to hypoxia in the newborn rat is due to an increase in a bioactive, nonimmunoassayable form of ACTH. To evaluate this phenomenon, we pretreated neonatal rats with a novel, specific, neutralizing anti-ACTH antibody (ALD1611) (20 mg/kg or 1 mg/kg IP) on the morning of PD1, PD7, and PD14. Twenty-four hours later, we measured hypoxia- or ACTH-stimulated plasma ACTH and corticosterone. For long-term effects, ALD1611 was given on PD1 and pups were studied on PD8 and PD15. Pretreatment with ALD1611 significantly decreased baseline corticosterone and completely blocked the corticosterone response to hypoxia and exogenous ACTH stimulation at all ages. The effect of 1 mg/kg ALD1611 on PD1 had dissipated by PD15. The decrease in corticosterone in ALD1611-treated pups was associated with decreases in baseline and hypoxia- and ACTH-stimulated adrenal Ldlr, Mrap, and Star mRNA expression at all ages. The adrenal response to hypoxia in the newborn rat is ACTH-dependent, suggesting the release of nonimmunoassayable, biologically active forms of ACTH. ALD1611 is useful as a tool to attenuate stress-induced, ACTH-dependent adrenal steroidogenesis in vivo.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Hormônio Adrenocorticotrópico/imunologia , Anticorpos Monoclonais/farmacologia , Anticorpos Neutralizantes/farmacologia , Corticosterona/sangue , Glândulas Suprarrenais/metabolismo , Hormônio Adrenocorticotrópico/sangue , Hormônio Adrenocorticotrópico/farmacologia , Animais , Animais Recém-Nascidos , Feminino , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Hipóxia/metabolismo , Masculino , Fosfoproteínas/metabolismo , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de LDL/metabolismo
11.
Gen Comp Endocrinol ; 281: 145-152, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31199927

RESUMO

Amphibian populations are declining globally, so understanding how individuals respond to anthropogenic and environmental stressors may aid conservation efforts. Using a non-invasive water-borne hormone assay, we measured the release rates of two glucocorticoid hormones, corticosterone and cortisol, in Rio Grande Leopard frog, Rana berlandieri, tadpoles. We validated this method pharmacologically and biologically using an adrenocorticotropic hormone (ACTH) challenge, exposure to exogenous corticosterone, and an agitation test. We calculated the repeatability of hormone release rates, the recovery time from an acute stressor, and explored rearing methods for tadpoles. Tadpole corticosterone release rates increased following an ACTH challenge, exposure to exogenous corticosterone, and agitation, validating the use of water-borne hormone methods in this species. After exposure to an acute stressor via agitation, corticosterone release rates began to decline after 2 h and were lowest after 6 h, suggesting a relatively rapid recovery from an acute stressor. Tadpoles reared in groups had higher corticosterone release rates than tadpoles reared individually, and lost mass by Day 7, while tadpoles reared individually did not show a stress response, therefore either rearing method is viable, but have differing physiological costs for tadpoles. Repeatability of corticosterone release rates was moderate to high in R. berlandieri tadpoles, indicating that this species can show a response to selection and potentially respond to rapid environmental change. Our results show that the water-borne hormone assay is a viable way to measure glucocorticoids in this species and is useful in the field of conservation physiology for rare and endangered species.


Assuntos
Cruzamento/métodos , Corticosterona/metabolismo , Hidrocortisona/metabolismo , Estresse Fisiológico , Hormônio Adrenocorticotrópico/farmacologia , Animais , Larva/efeitos dos fármacos , Larva/metabolismo , Rana pipiens/metabolismo , Reprodutibilidade dos Testes , Estresse Fisiológico/efeitos dos fármacos
12.
J Vet Intern Med ; 33(4): 1766-1774, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31111575

RESUMO

BACKGROUND: The hypothalamic-pituitary-adrenal axis regulates the response to sepsis-associated stress. Relative adrenal insufficiency or adrenocorticotropic hormone (ACTH):cortisol imbalance, defined as a poor cortisol response to administration of ACTH, is common and associated with death in hospitalized foals. However, information on other adrenal steroid response to ACTH stimulation in sick foals is minimal. OBJECTIVE: To investigate the response of multiple adrenocortical steroids to administration of ACTH in foals. ANIMALS: Hospitalized (n = 34) and healthy (n = 13) foals. METHODS: In this prospective study, hospitalized foals were categorized into 2 groups using cluster analysis based on adrenal steroids response to ACTH stimulation: Cluster 1 (n = 11) and Cluster 2 (n = 23). After baseline blood sample collection, foals received 10 µg of ACTH with additional samples collected at 30 and 90 minutes after ACTH. Steroid and ACTH concentrations were determined by immunoassays. The area under the curve (AUC) and Delta0-30 were calculated for each hormone. RESULTS: The AUC for cortisol, aldosterone, androstenedione, pregnenolone, 17α-OH-progesterone, and progesterone were higher in critically ill (Cluster 1) compared to healthy foals (P < .01). Delta0-30 for cortisol and 17α-OH-progesterone was lower in Cluster 1 (24%, 26.7%) and Cluster 2 (16%, 11.2%) compared to healthy foals (125%, 71%), respectively (P < .05). Foals that died had increased AUC for endogenous ACTH (269 versus 76.4 pg/mL/h, P < .05) accompanied by a low AUC for cortisol (5.5 versus 15.5 µg/dL/h, P < .05), suggesting adrenocortical dysfunction. CONCLUSION AND CLINICAL IMPORTANCE: The 17α-OH-progesterone response to administration of ACTH was a good predictor of disease severity and death in hospitalized foals.


Assuntos
Corticosteroides/sangue , Hormônio Adrenocorticotrópico/farmacologia , Doenças dos Cavalos/sangue , Doenças dos Cavalos/tratamento farmacológico , 17-alfa-Hidroxiprogesterona/sangue , Hormônio Adrenocorticotrópico/administração & dosagem , Animais , Animais Recém-Nascidos , Área Sob a Curva , Análise por Conglomerados , Estado Terminal , Feminino , Doenças dos Cavalos/mortalidade , Cavalos , Masculino , Prognóstico , Estudos Prospectivos , Sepse/tratamento farmacológico , Sepse/veterinária
13.
J Vis Exp ; (145)2019 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-30933075

RESUMO

The hormone which the adrenal cortex secretes is vital for animals against stress and diseases. The method described here is the procedure of primary cultured rat adrenal cells and related functional assays (immunofluorescence staining of lipid droplet surface protein, as well as corticosterone analysis). Unlike an in vivo model, the variation of interexperiments in adrenal monolayer cultures is less and the experimental condition is easy to control. Besides, the source of rats is also more stable than other animals, like bovine ones. There are also several human adrenal cell lines (NCI-H295, NCI-H295R, SW13, etc.) that can be used in adrenal studies. However, the steroid production of these lines will still be influenced by numerous factors, which include serum lot number, passage number, mutant/loss of distinct genes, etc. Except for lacking 17α-hydroxylase, the primary culture of rat adrenocortical cells is a better and more convenient technique for studying adrenal physiology. In summary, primary rat adrenal cultures could be a good in vitro platform for researchers to investigate the mechanisms of the reagent of interest in the adrenal gland system.


Assuntos
Córtex Suprarrenal/citologia , Esteroides/biossíntese , Hormônio Adrenocorticotrópico/farmacologia , Animais , Células Cultivadas , Corticosterona/metabolismo , Feminino , Masculino , Ratos Sprague-Dawley
14.
Gen Comp Endocrinol ; 280: 147-157, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31009603

RESUMO

Monitoring glucocorticoids in faeces and hair is increasingly used in ecological studies and provides a powerful and minimally intrusive mean to identify physiological challenges faced by wild animals. Using a cortisol and a corticosterone immunoassays, we conducted an adrenocorticotropic (ACTH) challenge with five weekly repeated injections to validate the use of faecal glucocorticoid metabolites and hair cortisol concentration as biological markers of the HPA-axis activity in captive mountain goats (Oreamnos americanus). We also investigated the effect of endogenous (age, sex, reproductive status) and methodological (faecal sample collection date, freezing delay and hair type) variables on cortisol values using faecal and hair samples collected from marked wild mountain goats during a long-term study. The cortisol enzyme immunoassay was reliable for mountain goat faeces and hair, and was sensitive enough to detect a clear rise in glucocorticoid concentration following ACTH injections for both matrices. Age and sex had no detectable effect on faecal glucocorticoid metabolites, but hair cortisol concentration was higher in kids and yearlings than in older goats, and lower in adult males compared to adult females. Reproductive status had no detectable effect on both faecal and hair measurements. Faecal metabolite concentrations increased with sample collection date in late spring until mid-summer and decreased afterward until early fall. Guard hair had nearly twice as much cortisol per gram as undercoat hair. Prolonged delay to freezing reduced the concentration of faecal glucocorticoid metabolites, but degradation seemed limited when samples were exposed to wind and sun or when ambient temperature was low. We conclude that faeces and hair can be used as valid biomarkers of the HPA-axis activity in mountain goat provided that confounding variables are taken into account when interpreting measurements.


Assuntos
Biomarcadores/metabolismo , Fezes/química , Cabras/metabolismo , Cabelo/metabolismo , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Metaboloma , Hormônio Adrenocorticotrópico/farmacologia , Envelhecimento/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Corticosterona/metabolismo , Feminino , Glucocorticoides/metabolismo , Cabelo/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Técnicas Imunoenzimáticas , Masculino , Reprodutibilidade dos Testes , Reprodução
15.
Bull Exp Biol Med ; 166(6): 754-758, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31028579

RESUMO

We studied immunocorrecting effects of Semax (Met-Glu-His-Phe-Pro-Gly-Pro) on the model of "social" stress caused by sensory contact and intermale confrontation. Functional activity of the immune system of laboratory animals was evaluated in standard immunopharmacological tests: delayed-type hypersensitivity reaction, direct agglutination test, latex test for studying phagocytic activity of peripheral blood neutrophils, changes in differential leukocyte count, and weight of immunocompetent organs. It was found that changes in the immune response caused by "social" stress are multidirectional, which confirms the theory of stress-induced "immune imbalance". Semax acted as effective immune corrector restoring cellular and humoral immunogenesis reactions and phagocytic activity of neutrophils. This attested to the presence of immunomodulating properties in Semax and necessitates further studies in this field.


Assuntos
Hormônio Adrenocorticotrópico/análogos & derivados , Fatores Imunológicos/farmacologia , Fármacos Neuroprotetores/farmacologia , Nootrópicos/farmacologia , Fragmentos de Peptídeos/farmacologia , Estresse Psicológico/tratamento farmacológico , Hormônio Adrenocorticotrópico/farmacologia , Agressão , Animais , Animais não Endogâmicos , Hipersensibilidade Tardia/tratamento farmacológico , Hipersensibilidade Tardia/imunologia , Imunidade Inata/efeitos dos fármacos , Testes de Fixação do Látex , Contagem de Leucócitos , Masculino , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Fagocitose/efeitos dos fármacos , Estresse Psicológico/imunologia , Estresse Psicológico/fisiopatologia
16.
BMC Vet Res ; 15(1): 71, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30832653

RESUMO

BACKGROUND: The sustainability of farming and animal welfare requires the reconsideration of current selection schemes. In particular, implementation of new selection criteria related to animal health and welfare should help to produce more robust animals and to reduce anti-microbial use. The hypothalamo-pituitary-adrenocortical (HPA) axis plays a major role in metabolic regulation and adaptation processes and its activity is strongly influenced by genetic factors. A positive association between HPA axis activity and robustness was recently described. To explore whether selecting pigs upon HPA axis activity could increase their robustness, a divergent selection experiment was carried out in the Large White pig breed. This allowed the generation of low (HPAlo) and high (HPAhi) responders to adrenocorticotropic hormone administration. RESULTS: In this study, we compared 23 hematologic and immune parameters of 6-week-old, HPAlo and HPAhi piglets and analysed their response to a low dose of lipopolysaccharide (LPS) two weeks later. At six weeks of age, HPAhi piglets displayed greater red blood cell and leucocyte number including CD8α+ γδ cells, cytotoxic T lymphocytes, naive T helper (Th) cells and B lymphocytes as compared to HPAlo individuals. The ability of blood cells to secrete TNFα in response to LPS ex vivo was higher for HPAhi pigs. At week eight, the inflammatory response to the LPS in vivo challenge was poorly affected by the HPA axis activity. CONCLUSIONS: Divergent selection upon HPA axis activity modulated hematologic and immune parameters in 6-week-old pigs, which may confer an advantage to HPAhi pigs at weaning. However, HPAlo and HPAhi piglets did not exhibit major differences in the parameters analysed two weeks later, i. e. in 8-week-old pigs. In conclusion, chronic exposure to high cortisol levels in HPAhi pigs does not negatively impact immunity.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Seleção Genética , Sus scrofa/genética , Sus scrofa/imunologia , Animais , Contagem de Células Sanguíneas/veterinária , Feminino , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Lipopolissacarídeos/toxicidade , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sus scrofa/sangue , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/metabolismo
17.
Clin Immunol ; 201: 70-78, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30844442

RESUMO

We sought evidence for direct effects of repository corticotropin (RCI; an FDA-approved treatment for selected cases of SLE) on isolated human B lymphocytes activated by engagement of TLR9 and B cell receptors. ODN 2395/αIgM treatment was found to result in induction of 162 distinct mRNAs and suppression of 80 mRNAs at 24 h. RCI treatment resulted in suppression of 14 of the ODN 2395/αIgM -induced mRNAs (mean suppression to 23.6 ±â€¯3.1% of stimulated value). The RCI-suppressed mRNAs included two critical regulators of class switch recombination, AICDA and BATF. RCI treatment also resulted in induction of 5 of the ODN 2395/αIgM -suppressed mRNAs (mean induction by RCI = 7.65 ±â€¯2.34-fold). The RCI-induced mRNAs included SLAMF3, a cell surface receptor capable of inhibiting autoantibody responses. These studies reveal that RCI treatment of human B cells reverses key elements of the early mRNA response to TLR9 and B cell receptor engagement.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Linfócitos B/efeitos dos fármacos , Receptores de Antígenos de Linfócitos B/imunologia , Receptor Toll-Like 9/imunologia , Adulto , Linfócitos B/imunologia , Células Cultivadas , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Adulto Jovem
18.
Gen Comp Endocrinol ; 276: 60-68, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30836104

RESUMO

Using faecal matter to monitor stress levels in animals non-invasively is a powerful technique for elucidating the effects of biotic and abiotic stressors on free-living animals. To validate the use of droppings for measuring stress in southern pied babblers (Turdoides bicolor) we performed an ACTH challenge on captive individuals and determined the effect of temporary separation from their social group on their faecal glucocorticoid metabolite (fGCM) concentration. Additionally, we compared fGCM concentrations of captive babblers to those of wild conspecifics and examined the effects of dominance rank on fGCM concentration. We found droppings to be a suitable matrix for measuring physiological stress in babblers and that individual separation from the group caused an increase in fGCM levels. In addition, babblers temporarily held in captivity had substantially higher fGCM concentrations than wild individuals, indicating that babblers kept in captivity experience high levels of stress. In wild, free-living individuals, dominant males showed the highest levels of stress, suggesting that being the dominant male of a highly territorial social group is stressful. Non-invasive sampling allows field-based researchers to reduce disturbance related to monitoring adrenocortical function, thereby avoiding artificially increasing circulating corticosterone concentration as it is not necessary to physically restrain study animals.


Assuntos
Passeriformes/fisiologia , Estresse Fisiológico , Clima Tropical , Hormônio Adrenocorticotrópico/farmacologia , Animais , Corticosterona/sangue , Fezes/química , Feminino , Glucocorticoides/metabolismo , Técnicas Imunoenzimáticas , Masculino , Metaboloma , Passeriformes/sangue
19.
Gen Comp Endocrinol ; 275: 15-24, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30735671

RESUMO

Non-invasive measures of glucocorticoid (GC) hormones and their metabolites, particularly in feces and hair, are gaining popularity as wildlife management tools, but species-specific validations of these tools remain rare. We report the results of a validation on black-tailed prairie dogs (Cynomys ludovicianus), a highly social engineer of the grasslands ecosystem that has experienced recent population declines. We captured adult female prairie dogs and brought them into temporary captivity to conduct an adrenocorticotropic hormone (ACTH) stimulation test, assessing the relationship between plasma GC and fecal glucocorticoid metabolite (FGM) levels following a single injection of a low (4 IU/kg) or high dose (12 IU/kg) of ACTH, compared to a single injection of saline. We also gave repeated injections of ACTH to adult females to assess whether this would result in an increase of hair cortisol concentrations, compared with control individuals repeatedly injected with saline. A single injection of ACTH at either low or high dose peaked plasma cortisol levels after 30 min, and thereafter the cortisol levels declined until 120 min, where they returned to pre-treatment levels comparable to those of the saline injected group. Despite the significant elevation of plasma cortisol in the treatment groups following ACTH injection, the elevation of FGM levels in the treatment groups were not significantly different from those in the control group over the following 12 h. Repeated injection of a high dose of ACTH failed to increase hair cortisol concentration in treatment animals. Instead, hair cortisol levels remained comparable to the pre-treatment mean, despite an increase in post-treatment hair cortisol levels seen in the saline-injected group. The magnitude of increase in the saline control group was comparable to natural seasonal variation seen in unmanipulated individuals. These results highlight that while measurement of GCs and their metabolites in feces and hair are potentially valuable conservation tools for black-tailed prairie dogs, further validation work is required before these matrices can be to real-world conservation applications.


Assuntos
Técnicas de Diagnóstico Endócrino , Fezes/química , Glucocorticoides/análise , Cabelo/química , Sciuridae , Estresse Psicológico/diagnóstico , Hormônio Adrenocorticotrópico/farmacologia , Animais , Animais Selvagens , Técnicas de Diagnóstico Endócrino/veterinária , Feminino , Glucocorticoides/metabolismo , Cabelo/metabolismo , Hidrocortisona/análise , Hidrocortisona/metabolismo , Masculino , Valor Preditivo dos Testes , Distribuição Aleatória , Sciuridae/metabolismo , Estresse Psicológico/metabolismo
20.
Domest Anim Endocrinol ; 68: 32-38, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30784946

RESUMO

Increasing the feed efficiency of lean tissue gains is an important goal for improving sustainable pork production and profitability for swine producers. To study feed efficiency, genetic selection based on residual feed intake (RFI) was used to create two divergent lines. Low-RFI pigs consume less feed for equal weight gain compared with their less-efficient, high-RFI counterparts. As cortisol and insulin are important energy control and growth regulators, our objective was to evaluate the role of the adrenocorticotropic hormone (ACTH)-cortisol and the glucose-insulin axes in pigs divergently selected for RFI. Adrenocorticotropic hormone (0.2 IU/kg BW)-stimulated cortisol and non-esterified fatty acids (NEFA) concentrations and intravenous glucose tolerance test (IVGTT; 0.25 g/kg BW)-stimulated glucose, insulin, and NEFA concentrations were assessed in six low-RFI and six high-RFI gilts (68 ± 5.2 kg). Before the ACTH challenge, low-RFI gilts tended to have less baseline plasma cortisol (P = 0.08) but no difference in NEFA concentrations (P = 0.63) compared with high-RFI gilts. After the ACTH challenge, low-RFI gilts had less cortisol (P = 0.04) and NEFA concentrations (P = 0.05) compared with high-RFI gilts. Glucose, insulin, and NEFA concentrations did not differ between genetic lines before the IVGTT. After glucose infusion, low-RFI gilts had greater insulin concentrations (P = 0.003) but did not differ in glucose or NEFA concentrations compared with high-RFI gilts. These results indicate that genetic selection for reduced RFI (improved feed efficiency) resulted in less stress responsiveness and an increase in insulin after glucose infusion. These data have implications for identifying and selecting more feed efficient pigs and for understanding the physiological mechanisms underlying feed efficiency.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Metabolismo Energético/genética , Glucose/farmacologia , Suínos/genética , Animais , Glicemia , Cruzamento , Ácidos Graxos não Esterificados/sangue , Feminino , Glucose/administração & dosagem , Teste de Tolerância a Glucose , Hidrocortisona/sangue , Insulina/metabolismo , Suínos/fisiologia
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