RESUMO
Introduction: Stress may pose a serious challenge to immune homeostasis. Stress however also may prepare the immune system for challenges such as wounding or infection, which are likely to happen during a fight or flight stress response. Methods: In common carp (Cyprinus carpio L.) we studied the stress-induced redistribution of neutrophils into circulation, and the expression of genes encoding CXC chemokines known to be involved in the regulation of neutrophil retention (CXCL12) and redistribution (CXCL8), and their receptors (CXCR4 and CXCR1-2, respectively) in blood leukocytes and in the fish hematopoietic organ - the head kidney. The potential involvement of CXC receptors and stress hormone receptors in stress-induced neutrophil redistribution was determined by an in vivo study with selective CXCR inhibitors and antagonists of the receptors involved in stress regulation: glucocorticoid/mineralocorticoid receptors (GRs/MRs), adrenergic receptors (ADRs) and the melanocortin 2 receptor (MC2R). Results: The stress-induced increase of blood neutrophils was accompanied by a neutrophil decrease in the hematopoietic organs. This increase was cortisol-induced and GR-dependent. Moreover, stress upregulated the expression of genes encoding CXCL12 and CXCL8 chemokines, their receptors, and the receptor for granulocytes colony-stimulation factor (GCSFR) and matrix metalloproteinase 9 (MMP9). Blocking of the CXCR4 and CXCR1 and 2 receptors with selective inhibitors inhibited the stress-induced neutrophil redistribution and affected the expression of genes encoding CXC chemokines and CXCRs as well as GCSFR and MMP9. Discussion: Our data demonstrate that acute stress leads to the mobilization of the immune system, characterized by neutrophilia. CXC chemokines and CXC receptors are involved in this stress-induced redistribution of neutrophils from the hematopoietic tissue into the peripheral blood. This phenomenon is directly regulated by interactions between cortisol and the GR/MR. Considering the pivotal importance of neutrophilic granulocytes in the first line of defense, this knowledge is important for aquaculture, but will also contribute to the mechanisms involved in the stress-induced perturbation in neutrophil redistribution as often observed in clinical practice.
Assuntos
Carpas , Neutrófilos , Animais , Metaloproteinase 9 da Matriz/metabolismo , Hidrocortisona/farmacologia , Hidrocortisona/metabolismo , Granulócitos , Receptores de Quimiocinas/metabolismoRESUMO
In an ever-changing environment, an adaptive stress response is the pivotal regulatory mechanism to maintain allostasis. Physiologic responses to stressors enable to overcome potential threat. Glucocorticoid effects can be considered compensatory and adaptive, however prolonged or excessive glucocorticoid secretion can be also maladaptive and detrimental. Therefore, it must be tightly regulated. Apart from the essential hormonal feedback regulation, evidence accrues that cytokines, e.g., proinflammatory interleukin 1ß (IL-1ß), also play an important regulatory role in the stress axis. Here we focused on the potential role of CXC chemokines (CXCL8 and CXCL12) and their receptors (CXCR1, 2 and 4) in the regulation of the stress response in common carp. We studied changes in gene expression of CXC chemokines and CXCRs in the stress axis organs (hypothalamus-pituitary gland-head kidney) upon 11 h of restraint stress and we established how CXCR blocking affects the activation of the stress axis and the synthesis/conversion of cortisol. During restraint stress, gene expression of the majority of the proinflammatory CXCL8 and homeostatic CXCL12 chemokines and their receptors was upregulated in the stress axis organs. Inhibition of CXCR1-2 and CXCR4 differentially affected the expression of genes encoding stress-related molecules: hormones, binding proteins, receptors as well as expression of genes encoding IL-1ß and its receptor. Moreover, we observed that CXC chemokines, via interaction with their respective CXCRs, regulate gene expression of molecules involved in cortisol synthesis and conversion and consistently affect the level of cortisol released into the circulation during the stress response. We revealed that in fish, CXC chemokines and their receptors are important regulators of the stress response at multiple levels of the stress axis, with particularly pronounced effects on steroidogenesis and cortisol conversion in the head kidney.
Assuntos
Carpas , Hidrocortisona , Animais , Carpas/genética , Carpas/metabolismo , Glucocorticoides , Interleucina-8 , Receptores de Interleucina-8A/genéticaRESUMO
An amendment to this paper has been published and can be accessed via the original article.
RESUMO
BACKGROUND: Mannan-binding lectin (MBL) is a main component of the lectin pathway of the complement system. Lower MBL levels are associated with, among other conditions, hypothyroidism and adverse pregnancy outcomes. In turn, adverse pregnancy outcomes and infertility may result from hypothyroidism, even in patients with high normal Thyroid-stimulating hormone (TSH). The aim of this study was to determine if MBL level differs between women of reproductive age with low normal (< 2.5 mIU/l) and high normal (≥2.5 mIU/l) TSH. Associations with other parameters potentially affected by hypothyroidism were also evaluated. METHODS: Ninety five (95) patients with normal thyroid tests (TSH 0.27-4.2 mIU/l), aged 18-48 years, were prospectively enrolled. Several laboratory parameters were measured, including MBL level, thyroid tests and lipid profile. RESULTS: Serum MBL level was lower in women with TSH ≥ 2.5 mIU/l than with TSH < 2.5 mIU/l. This association was confirmed by univariate regression analysis. MBL level was significantly lower in patients with abnormally low HDLC/cholesterol ratio and a positive correlation was found between MBL level and HDL/cholesterol ratio. CONCLUSION: In women of reproductive age with normal thyroid tests, lower MBL is associated with high normal TSH and with less favourable lipid profile. Therefore treatment with L-thyroxine should be considered in women of reproductive age with TSH ≥ 2.5 mIU/l.
Assuntos
Biomarcadores/sangue , Hipotireoidismo/diagnóstico , Lectina de Ligação a Manose/sangue , Complicações na Gravidez/diagnóstico , Tireotropina/sangue , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Hipotireoidismo/sangue , Pessoa de Meia-Idade , Gravidez , Complicações na Gravidez/sangue , Resultado da Gravidez , Prognóstico , Adulto JovemRESUMO
This work presents the first study of the self-disproportionation of enantiomers via chromatography (SDEvC) of ß-aminophosphonic acid esters, several of which have been synthesized for the first time. Three types of structures were examined, N-acetylated, dipeptide construction with N-Cbz glycine, and a free amine. In the latter case, this is the first time that SDEvC has been reported for free amine amino acids. In all the three types of structures, significant SDE magnitudes (Δee's up to 55%) were exhibited underscoring the ubiquitous nature of the SDE phenomenon. Chemical models of homo- versus heterochiral intermolecular interactions are proposed to rationalize the SDE magnitude differences amongst these new ß-aminophosphonic acid derivatives. In addition, the incorporation of additional, competing binding modes to a molecule, was found to lead to a reduction of the SDE magnitude by shifting the intermolecular binding away from the stereogenic center and/or by leading to a convoluted binding system that disrupts the structured and relatively stable assemblies that give rise to the SDE.
Assuntos
Aminoácidos/química , Cromatografia/métodos , Fluoretos/química , Ácidos Fosfóricos/química , Acetilação , Dipeptídeos/química , Ésteres/síntese química , Ésteres/química , Ligação de Hidrogênio , EstereoisomerismoRESUMO
α-Amino acids (α-AAs) are in extremely high demand in nearly every sector of the food and health-related chemical industries and continue to be the subject of intense multidisciplinary research. The self-disproportionation of enantiomers (SDE) is an emerging and one of the least studied areas of α-AA or enantiomeric properties, critically important for their production and application. In the present work, we report a detailed study of the SDE via achiral, gravity-driven column chromatography for a set of N-acylated, N-carbonylated, N-fluoroacylated, and N-thioacylated α-amino acid esters. As well as thioacylation, attention was paid to the effect of altering the R group of the ester functionality, the side chain, or that of the acyl group attached to the amide nitrogen, whereby it was found that electron-withdrawing groups in the latter moiety had a pronounced effect on the magnitude and behavior of the resulting SDE phenomenon. Intriguingly, in the case of N-fluoroacylated derivatives, by favoring the formation of dimeric associates and effecting a strong bias toward homochiral associates over heterochiral associates, the SDE magnitude was greatly reduced contrary to intuitive expectations. Energy estimates resulted from DFT calculations.
Assuntos
Aminoácidos/química , Ésteres/química , Ésteres/síntese química , Acilação , Amidas/química , Cromatografia , Ligação de Hidrogênio , Concentração Osmolar , Solventes/química , EstereoisomerismoRESUMO
According to current recommendations, a TSH value of <2.5 mIU/l should be maintained during preconception and pregnancy. The same recommendation, however, does not relate to all women of childbearing age. The aim of the study was to evaluate relationship between lipid peroxidation (LPO; index of oxidative damage to membrane lipids) and thyroid tests and other parameters, which may be affected by thyroid dysfunction, in euthyroid women of childbearing age. Ninety nine female inpatients with normal thyroid tests (TSH 0.27-4.2 mIU/l), aged 18-48 years, were prospectively enrolled. Blood concentrations of malondialdehyde+4-hydroxyalkenals (LPO index) were measured spectrophotometrically. Thyroid tests (TSH, FT4, FT3), thyroid antibodies and other laboratory parameters [cholesterol, HDL cholesterol (HDLC), LDL cholesterol, HDLC/cholesterol ratio, triglycerides, glucose, CRP, iron] were measured with standard methods. Blood LPO level was higher in women with TSH≥2.5 mIU/l than in women with TSH<2.5 mIU/l. Positive correlation was found between TSH concentration and LPO level (r=0.210, p=0.037). In the univariate regression analysis, blood LPO level did constitute the only independent factor associated with TSH≥2.5 mIU/l. Abnormal HDLC/cholesterol ratio occurred more frequently in subjects with TSH≥2.5 mIU/l. Additionally, LPO level correlated positively with triglyceride concentration (r=0.340, p=0.001), whereas it correlated negatively with HDLC concentration (r=-0.335, p=0.001) and with HDL/cholesterol ratio (r=-0.331, p=0.001). In conclusion, in women of childbearing age with normal thyroid tests, TSH≥2.5 mIU/l is associated with higher oxidative damage to membrane lipids and less favorable lipid profile, which supports our standpoint that TSH of less than 2.5 mIU/l should be maintained in all women of childbearing age.
Assuntos
Lipídeos de Membrana/metabolismo , Estresse Oxidativo , Testes de Função Tireóidea , Tireotropina/sangue , Adolescente , Adulto , Feminino , Humanos , Peroxidação de Lipídeos , Lipídeos/sangue , Modelos Logísticos , Malondialdeído/metabolismo , Pessoa de Meia-Idade , Adulto JovemRESUMO
OBJECTIVES: Hypoparathyroidism is the most frequent complication of thyroidectomy. The incidence rates of temporary and permanent postoperative hypoparathyroidism vary from 7 to more than 60% and from 0 to 9%, respectively. DESIGN: The aim of the study has been to evaluate the incidence of hypoparathyroidism and clinical manifestations of hypocalcaemia after total thyroidectomy, as well as assess factors that affect the frequency of the symptomatic hypocalcaemia, and benefits resulting from the measurement of parathyroid hormone (PTH) concentration on the first day after thyroidectomy. SETTING: The studied group consisted of 330 patients after total thyroidectomy, while the control group consisted of 86 patients who underwent total resection of one lobe only or subtotal thyroidectomy. RESULTS: Based on the measurements of serum PTH concentration on the first day after total thyroidectomy, postoperative hypoparathyroidism was diagnosed in 48% of patients. After total thyroidectomy, the frequency of clinical symptoms of hypocalcaemia was twice less than the incidence of hypoparathyroidism confirmed by biochemical testing. Total thyroidectomy occurred to be an independent factor of the increased risk of postoperative hypoparathyroidism. This risk was even higher in the cases widened by lymphadenectomy, and among patients with Graves' disease. In the group of patients with decreased serum PTH concentration the occurrence of clinical symptoms of hypocalcaemia significantly depended on serum PTH concentration - patients with lower PTH levels reported paresthesias more frequently. CONCLUSIONS: Serum PTH levels below 5 pg/ml seems to be a good prognostic factor of the occurrence of hypocalcaemia symptoms. The information about low PTH concentration allows to start the pharmacotherapy faster and avoid clinical manifestation of hypocalcaemia.
Assuntos
Hipocalcemia/etiologia , Hipoparatireoidismo/etiologia , Hormônio Paratireóideo/sangue , Doenças da Glândula Tireoide/cirurgia , Tireoidectomia/efeitos adversos , Adulto , Idoso , Cálcio/sangue , Feminino , Humanos , Hipocalcemia/sangue , Hipoparatireoidismo/sangue , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/etiologia , Prognóstico , Estudos RetrospectivosRESUMO
UNLABELLED: : 46 year old patient was admitted as an emergency with vomiting, hypotension and serum cortisol of 0,940 mug/dl (26 nmol/l) indicative of adrenal failure. Despite previous history of panhypopituitarism he was found to be hyperthyroid [free T4 6.32 ng/dl (ref. range: 0.93-1.7), free T3 22.21 pg/ml (ref. range: 1.8-4.6)]. He was fit and well till the age of 45. Eight months prior to this hospitalisation he presented with diabetes insipidus and was found to have a large cystic tumour in the area of the pituitary gland. Surgery was only partially successful and histologically the tumour was diagnosed as craniopharyngioma. Endocrine assessment revealed deficiency in ACTH-cortisol, growth hormone, and gonadotropin, as well as low-normal free T4. On the day of his emergency admission he looked ill and dehydrated, though was fully conscious and cooperative. Heart rate was 120 beats/min (sinus rhythm), blood pressure 85/40 mm Hg. There were no obvious features of infection, but there was marked tremor and thyroid bruit. He received treatment with intravenous fluids and hydrocortisone. L-thyroxine was stopped. Administration of large dose of methimazole (60 mg/day) resulted in gradual decrease in free T4 and free T3 (to 1.76 ng/ml, and 5.92 pg/ml, respectively) over a 15-day period. The patient was found to have increased titre of antithyroperoxidase (anti-TPO) and anti-TSH receptor (anti-TSHR) antibodies [2300 IU/l (ref. range <40) and 3.6 IU/l (ref. range <1.0), respectively]. He was referred for radioactive iodine treatment. Iodine uptake scan performed prior to radioiodine administration confirmed uniformly increased iodine uptake consistent with Graves' disease. CONCLUSION: Our case illustrates coexistence of hypopituitarism and clinically significant autoimmune thyroid disease. The presence of hypopituitarism does not preclude the development of autoimmune thyrotoxicosis.
RESUMO
UNLABELLED: INTRODUCTION, MATERIAL AND METHODS: Visfatin is a cytokine, mainly expressed in visceral fat, that exerts insulin-mimicking effects in rodents through activation of an insulin receptor, although the binding-site is distinct from that of insulin. However, the mechanisms that regulate visfatin synthesis are still not fully understood. In particular, it is not clear whether short-term glucose-induced hyperglycaemia and hyperinsulinaemia as well as a glucocorticoid-induced increase in insulin resistance are reflected in appreciable alterations in serum visfatin levels in humans. In order to investigate this we measured serum visfatin, glucose and insulin concentrations during a 75.0 gram oral glucose tolerance test (OGTT) [Study 1], as well as before and after oral administration of dexamethasone [Study 2]. Study 1 included 17 subjects (2 males), aged 35.7 +/- 15.6 (mean +/- SD) years of BMI 35.2 +/- 9.3 kg/m(2). Blood samples were taken before (0 minutes) and at 60 and 120 minutes after glucose administration. Study 2 included 20 subjects (4 males, 5 subjects with type 2 diabetes), aged 42.1 +/- 17.2 years of BMI 36.7 +/- 8.38 kg/m(2) who underwent screening for Cushing's disease/syndrome. Dexamethasone was administered at a dose of 0.5 mg every 6 hours for 48 hours. Fasting serum concentrations of visfatin, glucose and insulin were assessed before (D0) and after 48 hours of dexamethasone administration (D2). Insulin resistance was assessed according to the HOMA method in non-diabetic individuals (n = 15). RESULTS: In Study 1 two subjects were found to have impaired glucose tolerance and one subject was found to have diabetes mellitus. Glucose administration resulted in a highly significant increase in insulin (from 11.4 +/- 7.2 microU/mL at 0 min to 98.9 +/- 68.6 microU/mL at 60 min and 72.6 +/- 45.1 microU/mL at 120 minute of OGTT, p < 0.001 for 60 and 120 minutes in comparison to baseline). However, there was no change in serum visfatin concentrations (84.6 +/- 11.6 ng/mL at 0 minutes, 82.6 +/- 12.7 ng/mL at 60 minutes and 81.1 +/- 14.5 ng/mL at 120 minutes of OGTT, p = ns). All subjects in Study 2 achieved suppression of cortisol concentrations below 50 nmo/l. Dexamethasone administration resulted in an increase in fasting insulin (from 11.5 +/- 6.9 to 16.9 +/- 7.6 microU/mL; p = 0.011) and an increase in HOMA (from 2.73 +/- 1.74 to 4.02 +/- 2.27; p = 0.015), albeit without a significant change in serum visfatin concentrations (61.1 +/- 19.8 vs. 68.3 +/- 19.4 ng/mL, p = ns). In neither Study 1 nor Study 2 was there any significant correlation between serum visfatin and age, BMI or HOMA. CONCLUSIONS: There is a striking difference between the marked rise in insulin concentrations and the lack of change in visfatin concentrations during the oral glucose tolerance test. This implies that it is highly unlikely that visfatin is involved in the short-term regulation of glucose homeostasis in human subjects. Dexamethasone administration (4 mg/48 hours) induces an increase in insulin resistance, although without significant change in serum visfatin concentrations. Therefore in contrast to the in vitro data, short term glucocorticoid administration does not result in appreciable changes in serum levels of this adipocytokine. Furthermore, the results of our study do not support the notion that glucocorticoid-induced insulin resistance is likely to be related to changes in serum concentrations of visfatin.
Assuntos
Glicemia/metabolismo , Dexametasona/farmacologia , Resistência à Insulina , Insulina/sangue , Nicotinamida Fosforribosiltransferase/sangue , Adulto , Índice de Massa Corporal , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
AIM: The aim of this study was to examine the expression of the IGF-I gene and of genes for IGFBP-1, -2, -3, and -4 in cells from nodular goiters (NG), and from different human thyroid carcinomas (papillary--PTC, anaplastic--ATC, and medullary--MTC), cultured in monolayers. The influence, exerted by exogenous IGF-I on the expression of these genes, was also investigated. METHODS: Thyroid tissue specimens were obtained from 65 patients during subtotal or total thyroidectomies. After approximately 2-3 weeks of culture, thyroid cells were incubated for 24 hours with IGF-I in concentrations of: 0, 1, 10 and 100 ng/ml. The total mRNA was isolated according to the method described by Chomczynski and Sacchi with our own modifications. Afterwards, mRNA encoding IGF-I, IGFBP-1-IGFBP-4 and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), were amplified, using the reverse transcription-polymerase chain reaction (RT-PCR); GAPDH gene served as a control gene. PCR products were electrophoresed and then submitted to densitometric analysis. RESULTS AND CONCLUSIONS: Our study has shown that in carcinoma cells (ATC, PTC, MTC), IGF-I reveals a stimulatory influence on the expression of its own gene, that effect being most distinctive in ATC cells. These facts indicate an important role of IGF-I in the pathogenesis and invasiveness of the analyzed malignant neoplasms.