RESUMO
A simple and efficient method for obtaining monospecies and binary Staphylococcus aureus and Staphylococcus epidermidis cultures in sodium alginate gel matrix mimicking the natural microenvironment of the nasal cavity was proposed. The cultures were used for studying the effect of norepinephrine on monospecies and binary communities of two types of bacteria, S. aureus (invasive strain) and S. epidermis (commensal strain). After 24-h incubation, S. aureus predominated in the binary community, but later it was replaced by S. epidermis. Norepinephrine at higher concentrations accelerated this process without principally changing it. The model can be used to develop more effective complex antimicrobial drugs.
Assuntos
Alginatos , Norepinefrina , Staphylococcus aureus , Staphylococcus epidermidis , Alginatos/farmacologia , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Norepinefrina/farmacologia , Ácidos Hexurônicos/farmacologia , Ácido Glucurônico/farmacologia , Géis/farmacologia , Catecolaminas/farmacologia , Catecolaminas/metabolismo , Antibacterianos/farmacologiaRESUMO
BACKGROUND: "Metacontrol" describes the ability to maintain an optimal balance between cognitive control styles that are either more persistent or more flexible. Recent studies have shown a link between metacontrol and aperiodic EEG patterns. The present study aimed to gain more insight into the neurobiological underpinnings of metacontrol by using methylphenidate (MPH), a compound known to increase postsynaptic catecholamine levels and modulate cortical noise. METHODS: In a double-blind, randomized, placebo-controlled study design, we investigated the effect of MPH (0.5 mg/kg) on aperiodic EEG activity during a flanker task in a sample of n = 25 neurotypical adults. To quantify cortical noise, we employed the fitting oscillations and one over f algorithm. RESULTS: Compared with placebo, MPH increased the aperiodic exponent, suggesting that it reduces cortical noise in 2 ways. First, it did so in a state-like fashion, as the main effect of the drug was visible and significant in both pre-trial and within-trial periods. Second, the electrode-specific analyses showed that the drug also affects specific processes by dampening the downregulation of noise in conditions requiring more control. CONCLUSIONS: Our findings suggest that the aperiodic exponent provides a neural marker of metacontrol states and changes therein. Further, we propose that the effectiveness of medications targeting catecholaminergic signaling can be evaluated by studying changes of cortical noise, fostering the idea of using the quantification of cortical noise as an indicator in pharmacological treatment.
Assuntos
Eletroencefalografia , Metilfenidato , Humanos , Método Duplo-Cego , Metilfenidato/farmacologia , Masculino , Adulto , Feminino , Eletroencefalografia/efeitos dos fármacos , Adulto Jovem , Estimulantes do Sistema Nervoso Central/farmacologia , Catecolaminas/metabolismo , Ondas Encefálicas/efeitos dos fármacosRESUMO
BACKGROUND: In humans with pheochromocytomas (PCCs), targeted metabolomics is used to determine the catecholamine phenotype or to uncover underlying pathogenic variants in tricarboxylic acid (TCA) cycle genes such as succinate dehydrogenase subunits (SDHx). HYPOTHESIS/OBJECTIVES: To analyze catecholamine contents and TCA cycle metabolites of PCCs and normal adrenals (NAs). ANIMALS: Ten healthy dogs, 21 dogs with PCC. METHODS: Prospective observational study. Dogs diagnosed with PCC based on histopathological and immunohistochemical confirmation were included. Tissue catecholamine contents and TCA metabolites in PCCs and NAs were measured by liquid chromatography with mass spectrometry or electrochemical detection. RESULTS: Compared to NAs, PCCs had significantly higher tissue proportion of norepinephrine (88% [median: range, 38%-98%] vs 14% [11%-26%]; P < .001), and significantly lower tissue proportion of epinephrine (12% [1%-62%] vs 86% [74%-89%]; P < .001). Pheochromocytomas exhibited significantly lower fumarate (0.4-fold; P < .001), and malate (0.5-fold; P = .008) contents than NAs. Citrate was significantly higher in PCCs than in NAs (1.6-fold; P = .015). One dog in the PCC group had an aberrant succinate : fumarate ratio that was 25-fold higher than in the other PCCs, suggesting an SDHx mutation. CONCLUSIONS AND CLINICAL IMPORTANCE: This study reveals a distinct catecholamine content and TCA cycle metabolite profile in PCCs. Metabolite profiling might be used to uncover underlying pathogenic variants in TCA cycle genes in dogs.
Assuntos
Neoplasias das Glândulas Suprarrenais , Catecolaminas , Ciclo do Ácido Cítrico , Doenças do Cão , Feocromocitoma , Animais , Cães , Feocromocitoma/veterinária , Feocromocitoma/metabolismo , Feocromocitoma/genética , Neoplasias das Glândulas Suprarrenais/veterinária , Neoplasias das Glândulas Suprarrenais/metabolismo , Neoplasias das Glândulas Suprarrenais/genética , Doenças do Cão/metabolismo , Doenças do Cão/genética , Masculino , Feminino , Catecolaminas/metabolismo , Estudos Prospectivos , Metabolômica , Fenótipo , Malatos/metabolismo , Norepinefrina/metabolismo , Fumaratos/metabolismo , Epinefrina/metabolismoRESUMO
Endothelial dysfunction may contribute to pathogenesis of Takotsubo cardiomyopathy, but mechanism underlying endothelial dysfunction in the setting of catecholamine excess has not been clarified. The study reports that D1/D5 dopamine receptor signaling and small conductance calcium-activated potassium channels contribute to high concentration catecholamine induced endothelial cell dysfunction. For mimicking catecholamine excess, 100 µM epinephrine (Epi) was used to treat human cardiac microvascular endothelial cells. Patch clamp, FACS, ELISA, PCR, western blot and immunostaining analyses were performed in the study. Epi enhanced small conductance calcium-activated potassium channel current (ISK1-3) without influencing the channel expression and the effect was attenuated by D1/D5 receptor blocker. D1/D5 agonists mimicked the Epi effect, suggesting involvement of D1/D5 receptors in Epi effects. The enhancement of ISK1-3 caused by D1/D5 activation involved roles of PKA, ROS and NADPH oxidases. Activation of D1/D5 and SK1-3 channels caused a hyperpolarization, reduced NO production and increased ROS production. The NO reduction was membrane potential independent, while ROS production was increased by the hyperpolarization. ROS (H2O2) suppressed NO production. The study demonstrates that high concentration catecholamine can activate D1/D5 and SK1-3 channels through NADPH-ROS and PKA signaling and reduce NO production, which may facilitate vasoconstriction in the setting of catecholamine excess.
Assuntos
Células Endoteliais , Epinefrina , Espécies Reativas de Oxigênio , Transdução de Sinais , Humanos , Transdução de Sinais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Óxido Nítrico/metabolismo , Catecolaminas/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Baixa/metabolismo , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Endotélio Vascular/efeitos dos fármacos , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , NADPH Oxidases/metabolismo , Receptores de Dopamina D5/metabolismo , Receptores de Dopamina D1/metabolismo , Receptores Dopaminérgicos/metabolismoRESUMO
BACKGROUND: Myocardial injury (MI) after acute ischemic stroke (AIS) poses a significant threat to patient prognosis. However, effective intervention strategies are currently lacking. PURPOSE: To elucidate the mechanism of MI after AIS and effects of Naoxintong capsule (NXT) therapy. METHOD: In vivo, after a rat model of middle cerebral artery occlusion (MCAO)-induced MI was established and assessed. NXT was administered prophylactically to evaluate its pharmacodynamic effects and mechanisms. In vitro, a noradrenaline (NA)-induced damage cell model was constructed. Subsequently, the NXT was applied to the cell models to examine its cardioprotective effects and potential mechanisms. RESULTS: The in vivo findings revealed that following MCAO, there was a notable upregulation of TH expression in the rat brain, which subsequently triggered an increase in serum levels of various biomarkers, including AD, NA, AST, cTnT, CK-MB, and NT-proBNP. Histological analysis employing H&E staining and TUNEL assay disclosed significant pathological alterations and an escalation in apoptotic activity within the myocardial tissue. The myocardial tissue exhibited elevated levels of MDA alongside diminished CAT activity. Additionally, a marked increase in the Bax/Bcl-2 ratio, Cytochrome C release, and Caspase-3 activation was observed, all of which are indicative of heightened apoptotic activity. Administration of the NXT intervention successfully attenuated TH expression in the brains of rats subjected to MCAO, consequently leading to a reduction in circulating levels of catecholamines (CAs). NXT also exhibited significant efficacy at ameliorating cardiac oxidative stress and reducing apoptosis. In vitro, stimulation with NA led to an increase in ROS levels and calcium ion concentration in H9c2 cardiomyocytes. However, the administration of NXT has been found to effectively alleviate these adverse effects, thereby protecting H9c2 cardiomyocytes from the deleterious consequences of oxidative stress and calcium dyshomeostasis. CONCLUSION: Overall, this study has demonstrated that increased CAs synthesis in the brain after AIS in experimental rats led to a surge in circulating CAs, ultimately leading to MI. NXT can alleviate MI due to cerebral ischemia by increasing improving brain catecholamine synthesis, cardiac oxidative stress, and apoptosis.
Assuntos
Apoptose , Catecolaminas , Medicamentos de Ervas Chinesas , AVC Isquêmico , Ratos Sprague-Dawley , Animais , Medicamentos de Ervas Chinesas/farmacologia , Masculino , AVC Isquêmico/tratamento farmacológico , Catecolaminas/metabolismo , Apoptose/efeitos dos fármacos , Ratos , Infarto da Artéria Cerebral Média/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Modelos Animais de Doenças , Miocárdio/metabolismo , Miocárdio/patologia , NorepinefrinaRESUMO
BACKGROUND: It is extremely essential to accurately differentiate pheochromocytoma from Adrenal incidentalomas (AIs) before operation, especially biochemical tests were inconclusive. We aimed to evaluate the value of magnetic resonance imaging (MRI) features to differentiate pheochromocytomas among adrenal tumors, among which the consequences of biochemical screening tests of catecholamines and/or catecholamine metabolites are positive. METHODS: With institutional review board approval, this study retrospectively compared 35 pheochromocytoma (PHEO) patients with 27 non-pheochromocytoma(non-PHEO) patients between January 2022 to September 2023, among which the consequences of biochemical screening tests of catecholamines and/or catecholamine metabolites are positive. T test was used for the independent continuous data and the chi-square test was used for categorical variables. Univariate and multivariate logistic regression were applied to find the independent variate of the features to differentiate PHEO from non-PHEO and ROC analysis was applied to evaluate the diagnostic value of the independent variate. RESULTS: We found that the T2-weighted (T2W) signal intensity in patients with pheochromocytoma was higher than other adrenal tumors, with greatly significant (p < 0.001). T2W signal intensity ratio (T2W nodule-to-muscle SI ratio) was an independent risk factor for the differential diagnosis of adrenal PHEOs from non-PHEOs. This feature alone had 91.4% sensitivity and 81.5% specificity to rule out pheochromocytoma based on optimal threshold, with an area under the receiver operating characteristics curve (AUCROC) of 0.910(95% C I: 0.833-0.987). CONCLUSION: Our study confirms that T2W signal intensity ratio can differentiate PHEO from non-PHEO, among which the consequences of biochemical screening tests of catecholamines and/or catecholamine metabolites are positive.
Assuntos
Neoplasias das Glândulas Suprarrenais , Imageamento por Ressonância Magnética , Feocromocitoma , Humanos , Feocromocitoma/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Feminino , Masculino , Pessoa de Meia-Idade , Diagnóstico Diferencial , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Adulto , Catecolaminas/metabolismo , Idoso , Curva ROC , Sensibilidade e EspecificidadeRESUMO
Perceptual decisions are often accompanied by a feeling of decision confidence. Where the parietal cortex is known for its crucial role in shaping such perceptual decisions, metacognitive evaluations are thought to additionally rely on the (pre)frontal cortex. Because of this supposed neural differentiation between these processes, perceptual and metacognitive decisions may be divergently affected by changes in internal (e.g., attention, arousal) and external (e.g., task and environmental demands) factors. Although intriguing, causal evidence for this hypothesis remains scarce. Here, we investigated the causal effect of two neuromodulatory systems on behavioral and neural measures of perceptual and metacognitive decision-making. Specifically, we pharmacologically elevated levels of catecholamines (with atomoxetine) and acetylcholine (with donepezil) in healthy adult human participants performing a visual discrimination task in which we gauged decision confidence, while electroencephalography was measured. Where cholinergic effects were not robust, catecholaminergic enhancement improved perceptual sensitivity, while at the same time leaving metacognitive sensitivity unaffected. Neurally, catecholaminergic elevation did not affect sensory representations of task-relevant visual stimuli but instead enhanced well-known decision signals measured over the centroparietal cortex, reflecting the accumulation of sensory evidence over time. Crucially, catecholaminergic enhancement concurrently impoverished neural markers measured over the frontal cortex linked to the formation of metacognitive evaluations. Enhanced catecholaminergic neuromodulation thus improves perceptual but not metacognitive decision-making.
Assuntos
Cloridrato de Atomoxetina , Catecolaminas , Tomada de Decisões , Eletroencefalografia , Metacognição , Humanos , Masculino , Feminino , Tomada de Decisões/fisiologia , Tomada de Decisões/efeitos dos fármacos , Metacognição/fisiologia , Adulto , Adulto Jovem , Catecolaminas/metabolismo , Cloridrato de Atomoxetina/farmacologia , Percepção Visual/fisiologia , Percepção Visual/efeitos dos fármacos , Inibidores da Captação Adrenérgica/farmacologia , Acetilcolina/metabolismoRESUMO
It has been reported that the clinical symptoms of functional dyspepsia (FD) exacerbate upon stress while the gender-related factors have been incompletely understood. This study aims to investigate the role of sex in chronic heterotypic stress (CHS)-induced autonomic and gastric motor dysfunction. For CHS, the rats were exposed to the combination of different stressors for 7 consecutive days. Subsequently, electrocardiography was recorded in anesthetized rats to evaluate heart rate variability (HRV) for the determination of autonomic outflow and sympathovagal balance. Solid gastric emptying (GE) was measured in control and CHS-loaded male and female rats. The immunoreactivities of catecholaminergic cell marker tyrosine hydroxylase (TH), choline acetyltransferase (ChAT), corticotropin releasing factor (CRF), and estrogen receptor (ER-α/ß) were evaluated in medullary and pontine brainstem sections by immunohistochemistry. Compared with the controls, CHS significantly delayed GE in males but not in females. There was no significant sex-related difference in parasympathetic indicator HF under either control or CHS conditions. Sympathetic indicator LF was significantly higher in control females compared to the males. The higher sympathetic output in females was found to be attenuated upon CHS; in contrast, the elevated sympathetic output was detected in CHS-loaded males. No sex- or stress-related effect was observed on ChAT immunoreactivity in the dorsal motor nucleus of N.vagus (DMV). In males, greater number of TH-ir cells was observed in the caudal locus coeruleus (LC), while they were more densely detected in the rostral LC of females. Regardless of sex, CHS elevated immunoreactivity of TH throughout the LC. Under basal conditions, greater number of TH-ir cells was detected in the rostral ventrolateral medulla (RVLM) of females. In contrast, CHS remarkably increased the number of TH-ir cells in the RVLM of males which was found to be decreased in females. There was no sex-related alteration in TH immunoreactivity in the nucleus tractus solitarius (NTS) of control rats, while CHS affected both sexes in a similar manner. Compared with females, CRF immunoreactivity was prominently observed in control males, while both of which were stimulated by CHS. ER-α/ß was found to be co-expressed with TH in the NTS and LC which exhibit no alteration related to either sex or stress status. These results indicate a sexual dimorphism in the catecholaminergic and the CRF system in brainstem which might be involved in the CHS-induced autonomic and visceral dysfunction occurred in males.
Assuntos
Ratos Sprague-Dawley , Caracteres Sexuais , Estresse Psicológico , Animais , Masculino , Feminino , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologia , Ratos , Rombencéfalo/metabolismo , Motilidade Gastrointestinal/fisiologia , Catecolaminas/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Sistema Nervoso Autônomo/fisiopatologia , Sistema Nervoso Autônomo/metabolismo , Frequência Cardíaca/fisiologia , Hormônio Liberador da Corticotropina/metabolismo , Esvaziamento Gástrico/fisiologia , Colina O-Acetiltransferase/metabolismoRESUMO
Endothelial dysfunction contributes to the pathogenesis of Takotsubo syndrome (TTS). However, the exact mechanism underlying endothelial dysfunction in the setting of TTS has not been completely clarified. This study aims to investigate the roles of angiotensin II (Ang II) and intermediate-conductance Ca2+-activated K+ (SK4) channels in catecholamine-induced endothelial dysfunction. Human cardiac microvascular endothelial cells (HCMECs) were exposed to 100⯵M epinephrine (Epi), mimicking the setting of TTS. Epi treatment increased the ET-1 concentration and reduced NO levels in HCMECs. Importantly, the effects of Epi were found to be mitigated in the presence of Ang II receptor blockers. Furthermore, Ang II mimicked Epi effects on ET-1 and NO production. Additionally, Ang II inhibited tube formation and increased cell apoptosis. The effects of Ang II could be reversed by an SK4 activator NS309 and mimicked by an SK4 channel blocker TRAM-34. Ang II also inhibited the SK4 channel current (ISK4) without affecting its expression level. Ang II could depolarize the cell membrane potential. Ang II promoted ROS release and reduced protein kinase A (PKA) expression. A ROS blocker prevented Ang II effect on ISK4. The PKA activator Sp-8-Br-cAMPS increased SK4 channel currents. Epinephrine enhanced the activity of ACE by activating the α1 receptor/Gq/PKC signal pathway, thereby promoting the secretion of Ang II. The study suggested that high-level catecholamine can increase Ang II release from endothelial cells by α1 receptors/Gq/PKC signal pathway. Ang II can inhibit SK4 channel current by increasing ROS generation and reducing PKA expression, thereby contributing to endothelial dysfunction.
Assuntos
Angiotensina II , Catecolaminas , Células Endoteliais , Espécies Reativas de Oxigênio , Angiotensina II/farmacologia , Humanos , Catecolaminas/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Epinefrina/farmacologia , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo , Apoptose/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Óxido Nítrico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células CultivadasRESUMO
ABSTRACT: Hypercatecholaminergic conditions are known to cause heart failure and cardiac fibrosis when severe. Although previous investigations have studied the effects of beta-blockade in experimental models of catecholaminergic states, the detailed benefits of beta-blockade in more realistic models of hyper-adrenergic states were less clear. In this study, we examined acute cardiac changes in rats with hyperacute catecholamine-induced heart failure with and without propranolol treatment. Male Sprague-Dawley rats (n = 12) underwent a 6-hour infusion of epinephrine and norepinephrine alone, with an additional propranolol bolus (1 mg/kg) at hour 1 (n = 6). Cardiac tissues were examined after 6 hours. Cardiac immunohistochemistry revealed significantly decreased expression of phosphorylated p-38 (left ventricle, P = 0.021; right ventricle, P = 0.021), with upregulation of reactive oxidative species and other profibrosis proteins, after catecholamine infusion alone. After 1 propranolol 1 mg/kg bolus, the levels of phosphorylated-p38 returned to levels comparable with sham (left ventricle, P = 0.021; right ventricle, P = 0.043), with additional findings including downregulation of the apoptotic pathway and profibrotic proteins. We conclude that catecholamine-induced heart failure exerts damage through the p-38 mitogen-activated protein kinase pathway and demonstrates profibrotic changes mediated by matrix metalloproteinase 9, alpha-smooth muscle actin, and fibroblast growth factor 23. Changes in these pathways attenuated acute catecholamine-induced heart failure after propranolol bolus 1 mg/kg. We conclude that propranolol bolus at 1 mg/kg is able to mediate the effects of catecholamine excess through the p-38 mitogen-activated protein kinase pathway, profibrosis, and extrinsic apoptosis pathway.
Assuntos
Antagonistas Adrenérgicos beta , Fibrose , Insuficiência Cardíaca , Norepinefrina , Propranolol , Ratos Sprague-Dawley , Proteínas Quinases p38 Ativadas por Mitógeno , Animais , Masculino , Propranolol/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Ratos , Antagonistas Adrenérgicos beta/farmacologia , Antagonistas Adrenérgicos beta/administração & dosagem , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/induzido quimicamente , Norepinefrina/metabolismo , Epinefrina/toxicidade , Epinefrina/administração & dosagem , Fosforilação , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Miocárdio/patologia , Miocárdio/metabolismo , Miocárdio/enzimologia , Catecolaminas/metabolismo , Espécies Reativas de Oxigênio/metabolismoRESUMO
Metabolic dysregulation of catecholamines (CAs) is implicated in various human diseases. Simultaneously analyzing these acidic and alkaline CAs and their metabolites poses a significant challenge for clinical detection. This study introduces an efficient method employing automated online solid-phase extraction coupled with tandem mass spectrometry (aoSPE-MS/MS). The method employs weak cation exchange (WCX) and mixed-mode anion exchange (MAX) adsorbents to fabricate an on-line solid-phase extraction (SPE) column, along with an automated injection and multi-valve switching capabilities. The setup allows for automated extraction and analysis of urine samples in 15â¯minutes while retaining a wide range of acidic and basic CAs and their metabolites. The applicability of this method was demonstrated by optimising the adsorbent dosage volume, extraction solvent, and extraction rate. The limits of detection (LODs) and limits of quantitation (LOQs) for the 8 CAs and their metabolites were determined using the aoSPE-MS/MS approach, with ranges of 0.0625 â¼ 62.5â¯ng/mL and 0.125 â¼ 125â¯ng/mL, respectively. Additionally, assessments were made on the linearity, accuracy, and precision within and between batches, as well as matrix and ionic effects, and spiked recoveries. The study discovered that the aoSPE-MS/MS technique simplifies operation, increases efficiency, saves time, and has low detection and quantification limits when detecting a wide range of acid and alkaline CAs and their metabolites in urine. The study successfully demonstrated the high-throughput and automated detection of the 8 CAs and their metabolites with varying acidity and alkalinity in human urine samples. This method is expected to be a potential powerful tool for clinical detection.
Assuntos
Catecolaminas , Limite de Detecção , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Humanos , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Catecolaminas/urina , Catecolaminas/metabolismo , Reprodutibilidade dos Testes , Concentração de Íons de Hidrogênio , AutomaçãoRESUMO
OBJECTIVE: Tyrosinase is a rate-limiting enzyme for the biosynthesis of melanin pigment in peripheral tissues, such as skin and the retina. We recently reported the expression and enzymatic activity of tyrosinase as well as its protective effects against oxidative stress-induced protein damage in the mouse brain. The functional role of tyrosinase in the central nervous system, however, remains largely unknown. In the present study, we investigated the involvement of tyrosinase in social behavior in mice. METHODS: Pigmented C57BL/10JMsHir (B10) and tyrosinase-deficient albino B10.C- Tyr c /Hir (B10-c) mice were subjected to the three-chamber sociability test to assess sociability and social novelty preference. In addition, we measured the mRNA expression of genes involved in catecholamine metabolism in the hippocampus by real-time quantitative PCR analysis. RESULTS: The results obtained showed that tyrosinase deficiency impaired social novelty preference, but not sociability in mice. We also found that the hippocampal expression of genes involved in catecholamine metabolism, such as monoamine oxidase A and catechol-O-methyltransferase , were significantly decreased in tyrosinase-deficient B10-c mice. CONCLUSION: These results suggest that tyrosinase activity is functionally involved in the phenotypic expression of social behavior, particularly social novelty preference, in mice. The present study will advance our understanding of the functional role of tyrosinase in the central nervous system.
Assuntos
Hipocampo , Camundongos Endogâmicos C57BL , Monofenol Mono-Oxigenase , Comportamento Social , Animais , Monofenol Mono-Oxigenase/metabolismo , Monofenol Mono-Oxigenase/genética , Hipocampo/metabolismo , Camundongos , Masculino , Monoaminoxidase/metabolismo , Monoaminoxidase/genética , Monoaminoxidase/deficiência , Comportamento Exploratório/fisiologia , Catecolaminas/metabolismo , Comportamento Animal/fisiologiaRESUMO
In eutocic labor, the autonomic nervous system is dominated by the parasympathetic system, which ensures optimal blood flow to the uterus and placenta. This study is focused on the detection of the quantitative presence of catecholamine (C) neurofibers in the internal uterine orifice (IUO) and in the lower uterine segment (LUS) of the pregnant uterus, which could play a role in labor and delivery. A total of 102 women were enrolled before their submission to a scheduled cesarean section (CS); patients showed a singleton fetus in a cephalic presentation outside labor. During CS, surgeons sampled two serial consecutive full-thickness sections 5 mm in depth (including the myometrial layer) on the LUS and two randomly selected samples of 5 mm depth from the IUO of the cervix. All histological samples were studied to quantify the distribution of A nerve fibers. The authors demonstrated a significant and notably higher concentration of A fibers in the IUO (46 ± 4.8) than in the LUS (21 ± 2.6), showing that the pregnant cervix has a greater concentration of A neurofibers than the at-term LUS. Pregnant women's mechanosensitive pacemakers can operate normally when the body is in a physiological state, which permits normal uterine contractions and eutocic delivery. The increased frequency of C neurofibers in the cervix may influence the smooth muscle cell bundles' activation, which could cause an aberrant mechano-sensitive pacemaker activation-deactivation cycle. Stressful circumstances (anxiety, tension, fetal head position) cause the sympathetic nervous system to become more active, working through these nerve fibers in the gravid cervix. They might interfere with the mechano-sensitive pacemakers, slowing down the uterine contractions and cervix ripening, which could result in dystocic labor.
Assuntos
Catecolaminas , Colo do Útero , Miométrio , Humanos , Feminino , Gravidez , Colo do Útero/metabolismo , Adulto , Catecolaminas/metabolismo , Miométrio/metabolismo , Contração Uterina , Fibras Nervosas/metabolismo , CesáreaRESUMO
INTRODUCTION: Pheochromocytomas and paragangliomas (PPGLs) typically secrete catecholamines and their metabolites (metanephrines [MN] and normetanephrine [NMN]). Catecholamines are synthesized by several enzymes: phenylalanine hydroxylase (encoded by PAH), tyrosine hydroxylase (TH), aromatic L-amino acid decarboxylase (DDC), dopamine ß-hydroxylase (DBH), and phenylethanolamine N-methyltransferase (PNMT). MN/NMN secretion varies between anatomical and molecular subgroups. The aim of this study was to assess the correlation between DNA methylation of catecholamine synthesis genes and MN/NMN secretion. METHODS: Gene promoter methylation of PAH, TH, AADC, DBH, and PNMT were extracted and calculated based on publicly available data. Comparisons and correlation analysis were performed between MN ± NMN (MN/NMN), NMN only, and neither/unknown secretion patterns. Methylation levels and MN/NMN patterns were compared by three genetic alteration subgroups: pseudohypoxia (PH), kinase signaling (KS), and others. RESULTS: A total of 178 cases were included. Methylation of PAH CpGs negatively correlated with probability for MN/NMN secretion (p < .05 for all CpGs) and positively with NMN-only secretion. NMN-only secreting tumors had significantly higher promoter methylation of PAH, DBH, and PNMT compared with MN/NMN-secreting tumors. MN/NMN-secreting PPGLs had mainly KS alterations (52.1%), whereas NMN-only PPGLs had PH alterations (41.9%). PPGLs in the PH versus KS group had gene promoter hypermethylation of PAH (p = .002), DBH (p = .02), and PNMT (p = .003). CONCLUSIONS: Promoter methylation of genes encoding catecholamine synthesis enzymes is strongly and inversely correlated with MN/NMN patterns in PPGLs. KS and PH-related tumors have distinct methylation patterns. These results imply that methylation is a key regulatory mechanism of catecholamine synthesis in PPGLs.
Assuntos
Neoplasias das Glândulas Suprarrenais , Catecolaminas , Metilação de DNA , Epigênese Genética , Paraganglioma , Feocromocitoma , Feocromocitoma/genética , Feocromocitoma/metabolismo , Feocromocitoma/patologia , Humanos , Paraganglioma/genética , Paraganglioma/metabolismo , Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/metabolismo , Neoplasias das Glândulas Suprarrenais/patologia , Catecolaminas/metabolismo , Catecolaminas/biossíntese , Regiões Promotoras Genéticas , Feminino , Masculino , Pessoa de Meia-Idade , Normetanefrina/metabolismo , Adulto , Feniletanolamina N-Metiltransferase/genética , Feniletanolamina N-Metiltransferase/metabolismo , Metanefrina/metabolismo , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismoRESUMO
AIMS: To evaluate the basal release of 6-nitrodopamine (6-ND) from human isolated seminal vesicles (HISV) and to characterize its action and origin. MAIN METHODS: Left HISV obtained from patients undergoing prostatectomy surgery was suspended in a 3-mL organ bath containing warmed (37 °C) and gassed (95%O2:5%CO2) Krebs-Henseleit's solution (KHS) with ascorbic acid. An aliquot of 2 mL of the supernatant was used to quantify catecholamines by LC-MS/MS. For functional studies, concentration-responses curves to catecholamines were obtained, and pEC50 and Emax values were calculated. Detection of tyrosine hydroxylase and S100 protein were also carried out by both immunohistochemistry and fluorescence in-situ hybridization assays (FISH). KEY FINDINGS: Basal release of 6-ND was higher than the other catecholamines (14.76 ± 14.54, 4.99 ± 6.92, 3.72 ± 4.35 and 5.13 ± 5.76 nM for 6-ND, noradrenaline, adrenaline, and dopamine, respectively). In contrast to the other catecholamines, the basal release of 6-ND was not affected by the sodium current (Nav) channel inhibitor tetrodotoxin (1 µM; 10.4 ± 8.9 and 10.4 ± 7.9 nM, before and after tetrodotoxin, respectively). All the catecholamines produced concentration-dependent HISV contractions (pEC50 4.1 ± 0.2, 4.9 ± 0.3, 5.0 ± 0.3, and 3.9 ± 0.8 for 6-ND, noradrenaline, adrenaline, and dopamine, respectively), but 6-ND was 10-times less potent than noradrenaline and adrenaline. However, preincubation with very low concentration of 6-ND (10-8 M, 30 min) produced significant leftward shifts of the concentration-response curves to noradrenaline. Immunohistochemical and FISH assays identified tyrosine hydroxylase in tissue epithelium of HISV strips. SIGNIFICANCE: Epithelium-derived 6-ND is the major catecholamine released from human isolated seminal vesicles and that modulates smooth muscle contractility by potentiating noradrenaline-induced contractions.
Assuntos
Dopamina , Norepinefrina , Glândulas Seminais , Humanos , Masculino , Norepinefrina/farmacologia , Norepinefrina/metabolismo , Glândulas Seminais/efeitos dos fármacos , Glândulas Seminais/metabolismo , Dopamina/metabolismo , Dopamina/farmacologia , Pessoa de Meia-Idade , Epitélio/metabolismo , Epitélio/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Idoso , Catecolaminas/metabolismoRESUMO
Effectively inhibition of amyloid ß (Aß) aggregation is considered an important method for treatment of the Alzheimer's disease. Herein, inspired by the ability of trans-clovamide to effectively inhibit Aß aggregation, we synthesized a series of structurally related catecholamine derivatives and tested them as Aß aggregation inhibitors using the Thioflavin T assay. The results show that they demonstrated a higher inhibitory rate against Aß aggregation. Furthermore, these compounds exhibited high water solubilities and low cytotoxicities. Additionally, transmission electron microscopy images and dynamic light scattering of their Aß aggregations were observed. Docking simulations revealed that the catechol moiety of the synthesized compounds can form hydrogen bonds with the key regions of Aß and thereby inhibit Aß aggregation.
Assuntos
Peptídeos beta-Amiloides , Catecolaminas , Simulação de Acoplamento Molecular , Agregados Proteicos , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Catecolaminas/metabolismo , Humanos , Agregados Proteicos/efeitos dos fármacos , Relação Estrutura-Atividade , Estrutura Molecular , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Relação Dose-Resposta a DrogaRESUMO
We performed a comparative analysis of direct and mediated through the maternal organism effects of elevated catecholamine concentration on changes in the cardiac activity parameters in female rats and their fetuses on gestation days 18 and 20 under in vivo conditions. Administration of L-DOPA, a precursor of catecholaminergic transmitters, did not cause chronotropic effects in fetuses. Analysis of HR variability showed that in fetuses, irrespective of the administration route, there was an increase in nervous influences while the leading role of humoral-metabolic factors in the regulation of HR was preserved. In females receiving L-DOPA injection on day 18 of gestation, a decrease in humoral-metabolic and an increase in nerve effects were observed; in rats injected with L-DOPA on day 20 of gestation, an increase in sympathetic influences was found. Administration of L-DOPA to fetuses provoked a slight increase in the power of all components of the heart rhythm periodogram spectrum in females on day 18 of gestation and their decrease on day 20. Changes in the parameters of HR variability in females can confirm the hypothesis that in the "mother-fetus" system, the heart rhythm in the mother can be affected by both maternal and fetal influences presumably through the humoral-metabolic regulation.
Assuntos
Catecolaminas , Feto , Levodopa , Animais , Feminino , Ratos , Gravidez , Levodopa/farmacologia , Catecolaminas/metabolismo , Feto/metabolismo , Feto/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Ratos Wistar , Frequência Cardíaca Fetal/efeitos dos fármacos , Frequência Cardíaca Fetal/fisiologiaRESUMO
Fibromyalgia (FM) is characterized by chronic widespread musculoskeletal pain accompanied by fatigue and muscle atrophy. Although its etiology is not known, studies have shown that FM patients exhibit altered function of the sympathetic nervous system (SNS), which regulates nociception and muscle plasticity. Nevertheless, the precise SNS-mediated mechanisms governing hyperalgesia and skeletal muscle atrophy in FM remain unclear. Thus, we employed two distinct FM-like pain models, involving intramuscular injections of acidic saline (pH 4.0) or carrageenan in prepubertal female rats, and evaluated the catecholamine content, adrenergic signaling and overall muscle proteolysis. Subsequently, we assessed the contribution of the SNS to the development of hyperalgesia and muscle atrophy in acidic saline-injected rats treated with clenbuterol (a selective ß2-adrenergic receptor agonist) and in animals maintained under baseline conditions and subjected to epinephrine depletion through adrenodemedullation (ADM). Seven days after inducing an FM-like model with acidic saline or carrageenan, we observed widespread mechanical hyperalgesia along with loss of strength and/or muscle mass. These changes were associated with reduced catecholamine content, suggesting a common underlying mechanism. Notably, treatment with a ß2-agonist alleviated hyperalgesia and prevented muscle atrophy in acidic saline-induced FM-like pain, while epinephrine depletion induced mechanical hyperalgesia and increased muscle proteolysis in animals under baseline conditions. Together, the results suggest that reduced sympathetic activity is involved in the development of pain and muscle atrophy in the murine model of FM analyzed.
Assuntos
Clembuterol , Modelos Animais de Doenças , Fibromialgia , Hiperalgesia , Atrofia Muscular , Sistema Nervoso Simpático , Animais , Feminino , Fibromialgia/patologia , Fibromialgia/fisiopatologia , Atrofia Muscular/patologia , Atrofia Muscular/fisiopatologia , Hiperalgesia/fisiopatologia , Hiperalgesia/patologia , Sistema Nervoso Simpático/fisiopatologia , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/patologia , Clembuterol/farmacologia , Ratos , Carragenina/toxicidade , Ratos Sprague-Dawley , Dor/patologia , Dor/fisiopatologia , Epinefrina , Músculo Esquelético/patologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiopatologia , Catecolaminas/metabolismo , Agonistas Adrenérgicos beta/farmacologiaRESUMO
The pathophysiology of TTS is still elusive. This viewpoint proposes that TTS is an acute coronary syndrome, engendered by an ASNS/catecholamine-induced LVOTO, which results in an enhanced wall stress and afterload-based supply/demand mismatch, culminating in a segmental myocardial ischemic injury state, in susceptible individuals. Such individuals are felt to be particularly women with chronic hypertension, known or latent HCM, or non-HCM segmental myocardial hypertrophy, and certain structural abnormalities involving the LV and the MV apparatus. Recommendations are provided to explore further this hypothesis, while maintaining our focus on all other advanced TTS pathophysiology hypotheses for all patients, or those who do not experience LVOTO, men, the young, and patients with reverse, mid-ventricular, or right ventricular TTS, in whom more prolonged hyperadrenergic stimulation and/or larger amounts of blood-ridden catecholamines, segmental particularities of cardiac innervation and/or density of α-, and ß-adrenergic receptors, pheochromocytoma, neurological chronic or acute comorbidities/catastrophies, coronary epicardial/microvascular vasospasm, and CMD.
Assuntos
Cardiomiopatia de Takotsubo , Obstrução do Fluxo Ventricular Externo , Humanos , Cardiomiopatia de Takotsubo/fisiopatologia , Cardiomiopatia de Takotsubo/diagnóstico , Cardiomiopatia de Takotsubo/etiologia , Obstrução do Fluxo Ventricular Externo/fisiopatologia , Obstrução do Fluxo Ventricular Externo/etiologia , Obstrução do Fluxo Ventricular Externo/diagnóstico , Cardiomiopatia Hipertrófica/fisiopatologia , Cardiomiopatia Hipertrófica/diagnóstico , Cardiomiopatia Hipertrófica/complicações , Catecolaminas/metabolismo , Obstrução da Via de Saída Ventricular EsquerdaRESUMO
Stress cardiomyopathy (SCM) is associated with cardiovascular mortality rates similar to acute coronary syndrome. Myocardial injuries driven by inflammatory mechanisms may in part account for the dismal prognosis of SCM. Currently, no inflammation-targeted therapies are available to mitigate SCM-associated myocardial injuries. In this study, acute catecholamine surge-induced SCM was modeled by stimulating the ovariectomized (OVX) mice with isoproterenol (ISO). The effects of ginsenoside Rb1 (Rb1) on SCM-associated myocardial injuries were assessed in the OVX-ISO compound mice. RAW 264.7 macrophages stimulated with calf thymus DNA (ctDNA) or STING agonist DMXAA were adopted to further understand the anti-inflammatory mechanisms of Rb1. The results show that estrogen deprivation increases the susceptibility to ISO-induced myocardial injuries. Rb1 mitigates myocardial injuries and attenuates cardiomyocyte necrosis as well as myocardial inflammation in the OVX-ISO mice. Bioinformatics analysis suggests that cytosolic DNA-sensing pathway is closely linked with ISO-triggered inflammatory responses and cell death in the heart. In macrophages, Rb1 lowers ctDNA-stimulated production of TNF-α, IL-6, CCL2 and IFN-ß. RNA-seq analyses uncover that Rb1 offsets DNA-stimulated upregulation in multiple inflammatory response pathways and cytosolic DNA-sensing pathway. Furthermore, Rb1 directly mitigates DMXAA-stimulated STING activation and inflammatory responses in macrophages. In conclusion, the work here demonstrates for the first time that Rb1 protects against SCM-associated myocardial injuries in part by counteracting acute ISO stress-triggered cardiomyocyte necrosis and myocardial inflammation. Moreover, by evidencing that Rb1 downregulates cytosolic DNA-sensing machineries in macrophages, our findings warrant further investigation of therapeutic implications of the anti-inflammatory Rb1 in the treatment of SCM.