RESUMO
Post-traumatic stress disorder (PTSD) has become a major disease that threatens human health. Neurotransmitters and the amygdala are found to be critical in the development and maintenance of PTSD. We aim to investigate the role of glycyrrhizin in treating PTSD. Contextual fear extinction and elevated plus maze test were applied to evaluate the anxiety and fear memory. Microdialysis and high-performance liquid chromatography were used to analyze the expression of amygdala neurotransmitters in PTSD animal models and to verify the effects of glycyrrhizin on major neurotransmitters. The protein levels of tryptophan hydroxylase 2 (TPH2) were examined by western bolt. Glycyrrhizin treatment significantly reduced anxiety and fear memory after 1 and 7 days of PTSD modelling. In addition, glycyrrhizin treatment restored the circadian rhythm changes of serotonin and TPH2. The present study found a significant circadian rhythm change of serotonin in the amygdala in PTSD rats. Besides, glycyrrhizin treatment restored the altered serotonin diurnal fluctuations, which raises important implications for PTSD treatment.
Assuntos
Relógios Circadianos/efeitos dos fármacos , Extinção Psicológica/efeitos dos fármacos , Ácido Glicirrízico/farmacologia , Serotonina/metabolismo , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Estresse Psicológico/tratamento farmacológico , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/metabolismo , Animais , Ansiedade/metabolismo , Modelos Animais de Doenças , Medo/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Memória/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Wistar , Transtornos de Estresse Pós-Traumáticos/metabolismo , Estresse Psicológico/metabolismoRESUMO
Chronic pain conditions such as low back pain and osteoarthritis are the most prominent causes of disability worldwide. Morphine and other opioid drugs are the gold standard treatment for severe pain, including surgical pain, but the use of these drugs for chronic pain is limited largely because long term use of these drugs is associated with drug abuse and hyperalgesia which produces a negative impact on the treatment. Non-addictive treatments for chronic pain are, therefore, highly needed. Commonly used opioid drugs activate mu opioid receptors, resulting in an inhibition of tonic activity of nociceptive neurons. The rewarding effects of opioid drugs are also mediated via activation of mu opioid receptors and inhibition of GABA mediated control of the activity of dopamineregic neurons. Enhanced glutamate release and greater activity of NMDA glutamate receptors is linked to the hyperalgesic effects of opioid drugs. Evidence suggests that activation of serotonin (5-hydroxytryptamine; 5-HT)-1â¯A receptors modulates dopamine neurotransmission to inhibit rewarding effects of drugs of abuse. Activation of these receptors inhibits glutamate release from the sensory neurons to reduce pain transmission. To help develop strategies for improving therapeutics in chronic pain, and draw research interest in the synthesis of non-addictive opioid drugs which do not predispose to hyperalgesia, the present article concerns the potential mechanism involved in 5-HT-1â¯A receptor mediated inhibition of pain and reward.
Assuntos
Analgésicos/uso terapêutico , Encéfalo/efeitos dos fármacos , Dor Crônica/tratamento farmacológico , Percepção da Dor/efeitos dos fármacos , Limiar da Dor/efeitos dos fármacos , Receptor 5-HT1A de Serotonina/efeitos dos fármacos , Recompensa , Agonistas do Receptor 5-HT1 de Serotonina/uso terapêutico , Analgésicos/efeitos adversos , Analgésicos Opioides/efeitos adversos , Animais , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Dor Crônica/metabolismo , Dor Crônica/fisiopatologia , Dor Crônica/psicologia , Dopamina/metabolismo , Humanos , Transtornos Relacionados ao Uso de Opioides/metabolismo , Transtornos Relacionados ao Uso de Opioides/fisiopatologia , Transtornos Relacionados ao Uso de Opioides/psicologia , Receptor 5-HT1A de Serotonina/metabolismo , Agonistas do Receptor 5-HT1 de Serotonina/efeitos adversos , Transdução de Sinais/efeitos dos fármacosRESUMO
Carbon-11-labeled serotonin (5-hydroxytryptamine) 6 receptor (5-HT6R) antagonists, 1-[(2-bromophenyl)sulfonyl]-5-[11C]methoxy-3-[(4-methyl-1-piperazinyl)methyl]-1H-indole (O-[11C]2a) and 1-[(2-bromophenyl)sulfonyl]-5-methoxy-3-[(4-[11C]methyl-1-piperazinyl)methyl]-1H-indole (N-[11C]2a), 5-[11C]methoxy-3-((4-methylpiperazin-1-yl)methyl)-1-(phenylsulfonyl)-1H-indole (O-[11C]2b) and 5-methoxy-3-((4-[11C]methylpiperazin-1-yl)methyl)-1-(phenylsulfonyl)-1H-indole (N-[11C]2b), 1-((4-isopropylphenyl)sulfonyl)-5-[11C]methoxy-3-((4-methylpiperazin-1-yl)methyl)-1H-indole (O-[11C]2c) and 1-((4-isopropylphenyl)sulfonyl)-5-methoxy-3-((4-[11C]methylpiperazin-1-yl)methyl)-1H-indole (N-[11C]2c), 1-((4-fluorophenyl)sulfonyl)-5-[11C]methoxy-3-((4-methylpiperazin-1-yl)methyl)-1H-indole (O-[11C]2d) and 1-((4-fluorophenyl)sulfonyl)-5-methoxy-3-((4-[11C]methylpiperazin-1-yl)methyl)-1H-indole (N-[11C]2d), were prepared from their O- or N-desmethylated precursors with [11C]CH3OTf through O- or N-[11C]methylation and isolated by HPLC combined with SPE in 40-50% radiochemical yield, based on [11C]CO2 and decay corrected to end of bombardment (EOB). The radiochemical purity was >99%, and the molar activity (MA) at EOB was 370-740â¯GBq/µmol with a total synthesis time of â¼40-min from EOB.
Assuntos
Doença de Alzheimer/diagnóstico , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/síntese química , Antagonistas da Serotonina/síntese química , Doença de Alzheimer/diagnóstico por imagem , Radioisótopos de Carbono/química , Humanos , Indóis/química , Marcação por Isótopo , Compostos Radiofarmacêuticos/química , Receptores de Serotonina/química , Receptores de Serotonina/metabolismo , Antagonistas da Serotonina/químicaRESUMO
Despite the increased morbidity of ulcerative colitis (UC) in recent years, available treatments remain unsatisfactory. Pogostemon cablin has been widely applied to treat a variety of gastrointestinal disorders in clinic for centuries, in which patchouli alcohol (PA, C15H26O) has been identified as the major active component. This study attempted to determine the bioactivity of PA on dextran sulfate sodium (DSS)-induced mice colitis and clarify the mechanism of action. Acute colitis was induced in mice by 3% DSS for 7 days. The mice were then given PA (10, 20 and 40mg/kg) or sulfasalazine (SASP, 200mg/kg) as positive control via oral administration for 7 days. At the end of study, animals were sacrificed and samples were collected for pathological and other analysis. In addition, a metabolite profiling and a targeted metabolite analysis, based on the Ultra-Performance Liquid Chromatography coupled with mass spectrometry (UPLC-MS) approach, were performed to characterize the metabolic changes in plasma. The results revealed that PA significantly reduced the disease activity index (DAI) and ameliorated the colonic injury of DSS mice. The levels of colonic MPO and cytokines involving TNF-α, IFN-γ, IL-1ß, IL-6, IL-4 and IL-10 also declined. Furthermore, PA improved the intestinal epithelial barrier by enhancing the level of colonic expression of the tight junction (TJ) proteins, for instance ZO-1, ZO-2, claudin-1 and occludin, and by elevating the levels of mucin-1 and mucin-2 mRNA. The study also demonstrated that PA inhibited the DSS-induced cell death signaling by modulating the apoptosis related Bax and Bcl-2 proteins and down-regulating the necroptosis related RIP3 and MLKL proteins. By comparison, up-regulation of IDO-1 and TPH-1 protein expression in DSS group was suppressed by PA, which was in line with the declined levels of kynurenine (Kyn) and 5-hydroxytryptophan (5-HTP) in plasma. The therapeutic effect of PA was evidently reduced when Kyn was given to mice. In summary, the study successfully demonstrated that PA ameliorated DSS-induced mice acute colitis by suppressing inflammation, maintaining the integrity of intestinal epithelial barrier, inhibiting cell death signaling, and suppressing tryptophan catabolism. The results provided valuable information and guidance for using PA in treatment of UC.
Assuntos
Colite/induzido quimicamente , Colite/tratamento farmacológico , Colo/efeitos dos fármacos , Sulfato de Dextrana , Sesquiterpenos/uso terapêutico , Triptofano/metabolismo , Animais , Colite/metabolismo , Colite/patologia , Colo/metabolismo , Colo/patologia , Citocinas/análise , Masculino , Camundongos Endogâmicos BALB C , Pogostemon/química , Sesquiterpenos/químicaRESUMO
Obesity activates both innate and adaptive immune responses in adipose tissue. Elevated levels of eosinophils with depression of monocyte and neutrophil indicate the deficiencies in the immune system of morbidly obese individuals. Actually, adipose tissue macrophages are functional antigen-presenting cells that promote the proliferation of interferon-gamma (IFN-gamma)-producing CD4+ T cells in adipose tissue of obese subjects. Eventually, diet-induced obesity is associated with the loss of tissue homeostasis and development of type 1 inflammatory responses in visceral adipose tissue. Activity of inducible indoleamine 2,3-dioxygenase-1 (IDO-1) plays a major role under pro-inflammatory, IFN-gamma dominated settings. One of the two rate-limiting enzymes which can metabolize tryptophan to kynurenine is IDO-1. Tumor necrosis factor-alpha (TNF-alpha) correlates with IDO-1 in adipose compartments. Actually, IDO-1-mediated tryptophan catabolism due to chronic immune activation is the cause of reduced tryptophan plasma levels and be considered as the driving force for food intake in morbidly obese patients. Thus, decrease in plasma tryptophan levels and subsequent reduction in serotonin (5-HT) production provokes satiety dysregulation that leads to increased caloric uptake and obesity. However, after bariatric surgery, weight reduction does not lead to normalization of IDO-1 activity. Furthermore, there is a connection between arginine and tryptophan metabolic pathways in the generation of reactive nitrogen intermediates. Hence, abdominal obesity is associated with vascular endothelial dysfunction and reduced nitric oxide (NO) availability. IFN-gamma-induced activation of the inducible nitric oxide synthase (iNOS) and dissociation of endothelial adenosine monophosphate activated protein kinase (AMPK)- phosphoinositide 3-kinase (PI3K)-protein kinase B (Akt)- endothelial NO synthase (eNOS) pathway enhances oxidative stress production secondary to high-fat diet. Thus, reduced endothelial NO availability correlates with the increase in plasma non-esterified fatty acids and triglycerides levels. Additionally, in obese patients, folate-deficiency leads to hyperhomocysteinemia. Folic acid confers protection against hyperhomocysteinemia-induced oxidative stress.
Assuntos
Ácido Fólico/metabolismo , Cinurenina/metabolismo , Metionina/metabolismo , Obesidade/metabolismo , Pteridinas/metabolismo , Transdução de Sinais/fisiologia , Animais , Humanos , Inflamação/metabolismo , Inflamação/patologia , Obesidade/patologiaRESUMO
BACKGROUND: Standard prophylaxis for chemotherapy-induced nausea and vomiting (CINV) with highly emetogenic and anthracycline-cyclophosphamide-based chemotherapy includes a 5-hydroxytryptamine-3 receptor antagonist, a neurokinin-1 receptor antagonist (NK1RA), and corticosteroid therapy. NEPA is a fixed combination of netupitant and palonosetron. The primary objective of this analysis was to document the safety profile, including cardiac safety, of NEPA + dexamethasone in comparison with current therapies across all phase II/III trials. MATERIALS AND METHODS: This pooled analysis was based on data from 3,280 patients in 4 randomized, double-blind clinical trials. Patients were categorized into 1 of 3 pooled groups on the basis of actual treatment received: NEPA + dexamethasone, palonosetron + dexamethasone, and aprepitant + ondansetron/palonosetron + dexamethasone. Safety was assessed by number and frequency of adverse events (AEs) and changes from baseline electrocardiogram measures. RESULTS: Most patients were female and younger than 65 years of age. Demographic characteristics varied among studies and pooled groups. Frequencies of treatment-emergent AEs (TEAEs) and treatment-related AEs (TRAEs) were similar across groups. TEAEs were mostly mild and consistent with expected chemotherapy and disease-related AEs (hematologic events, hair loss, general weakness). TRAEs in ≥2% of patients were headache and constipation. Frequencies of cardiac TEAEs were similar across groups, with QT prolongation (1.6%), tachycardia (1.1%), and dyspnea (0.9%) the most common. Serious cardiac TEAEs were rare. CONCLUSION: NEPA was well-tolerated, with an AE profile as expected for the regimen. Sample size, demographic characteristics, study design, chemotherapy, and antiemetic regimen differences across the four studies may have contributed to differences in frequencies of neutropenia and alopecia. Adding an NK1RA to a CINV prophylaxis regimen can improve outcomes without additional toxicity. IMPLICATIONS FOR PRACTICE: Supportive care for cancer should ideally be efficacious, convenient, and well-tolerated. There have been concerns about cardiac safety with current antiemetic prophylactic agents, namely dolasetron and ondansetron. This pooled safety analysis demonstrates that the new oral fixed combination therapy NEPA can be safely added to an antiemetic regimen without increased toxicity.
Assuntos
Antieméticos/uso terapêutico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Isoquinolinas/uso terapêutico , Neoplasias/tratamento farmacológico , Piridinas/uso terapêutico , Quinuclidinas/uso terapêutico , Adulto , Idoso , Biomarcadores Farmacológicos , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Combinação de Medicamentos , Tratamento Farmacológico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Isoquinolinas/efeitos adversos , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Náusea/patologia , Náusea/prevenção & controle , Neoplasias/complicações , Neoplasias/patologia , Antagonistas dos Receptores de Neurocinina-1/uso terapêutico , Piridinas/efeitos adversos , Quinuclidinas/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Antagonistas do Receptor 5-HT3 de Serotonina/uso terapêutico , Vômito/induzido quimicamente , Vômito/patologia , Vômito/prevenção & controleRESUMO
Efavirenz is highly effective at suppressing HIV-1, and the WHO guidelines list it as a component of the first-line antiretroviral (ARV) therapies for treatment-naïve patients. Though the pharmacological basis is unclear, efavirenz is commonly associated with a risk for neuropsychiatric adverse events (NPAEs) when taken at the prescribed dose. In many patients these NPAEs appear to subside after several weeks of treatment, though long-term studies show that in some patients the NPAEs persist. In a recent study focusing on the abuse potential of efavirenz, its receptor psychopharmacology was reported to include interactions with a number of established molecular targets for known drugs of abuse, and it displayed a prevailing behavioral profile in rodents resembling an LSD-like activity. In this report, we discovered interactions with additional serotonergic targets that may be associated with efavirenz-induced NPAEs. The most robust interactions were with 5-HT3A and 5-HT6 receptors, with more modest interactions noted for the 5-HT2B receptor and monoamine oxidase A. From a molecular mechanistic perspective, efavirenz acts as a 5-HT6 receptor inverse agonist of Gs-signaling, 5-HT2A and 5-HT2C antagonist of Gq-signaling, and a blocker of the 5-HT3A receptor currents. Efavirenz also completely or partially blocks agonist stimulation of the M1 and M3 muscarinic receptors, respectively. Schild analysis suggests that efavirenz competes for the same site on the 5-HT2A receptor as two known hallucinogenic partial agonists (±)-DOI and LSD. Prolonged exposure to efavirenz reduces 5-HT2A receptor density and responsiveness to 5-HT. Other ARVs such as zidovudine, nevirapine and emtricitabine did not share the same complex pharmacological profile as efavirenz, though some of them weakly interact with the 5-HT6 receptor or modestly block GABAA currents.
Assuntos
Fármacos Anti-HIV/toxicidade , Benzoxazinas/toxicidade , Encéfalo/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacos , Inibidores da Transcriptase Reversa/toxicidade , Antagonistas da Serotonina/toxicidade , Alcinos , Animais , Fármacos Anti-HIV/metabolismo , Benzoxazinas/metabolismo , Ligação Competitiva , Encéfalo/metabolismo , Células CHO , Sinalização do Cálcio/efeitos dos fármacos , Cricetulus , Ciclopropanos , Relação Dose-Resposta a Droga , Agonismo Parcial de Drogas , Cobaias , Células HEK293 , Infecções por HIV/diagnóstico , Infecções por HIV/virologia , HIV-1/patogenicidade , Células HeLa , Humanos , Potenciais da Membrana , Inibidores da Monoaminoxidase/toxicidade , Ligação Proteica , Ensaio Radioligante , Receptores Muscarínicos/efeitos dos fármacos , Receptores Muscarínicos/genética , Receptores Muscarínicos/metabolismo , Receptores de Serotonina/genética , Receptores de Serotonina/metabolismo , Inibidores da Transcriptase Reversa/metabolismo , Fatores de Tempo , TransfecçãoRESUMO
Human tryptophan hydroxylase 2 (hTPH2) is the rate-limiting enzyme for serotonin biosynthesis in the brain. A number of naturally-occurring single nucleotide polymorphisms (SNPs) have been reported for hTPH2. We investigated the activity and kinetic characteristics of the most common missense polymorphism rs2887147 (A328 V/E; 0.92% allelic frequency for the two different reported SNPs at the same site) using bacterially expressed hTPH2. The recombinant full-length enzyme A328E had no measurable enzyme activity, but A328V displayed decreased enzyme activity (Vmax). A328V also displayed substrate inhibition and decreased stability compared to the wild-type enzyme. By contrast, in constructs lacking the N-terminal 150 amino acid regulatory domain, the A328V substitution had no effect; that is, there was no substrate inhibition, enzyme stabilities (for wild-type and A328V) were dramatically increased, and Vmax values were not different (while the A328E variant remained inactive). These findings, in combination with molecular modeling, suggest that substitutions at A328 affect catalytic activity by altering the conformational freedom of the regulatory domain. The reduced activity and substrate inhibition resulting from these polymorphisms may ultimately reduce serotonin synthesis and contribute to behavioral perturbations, emotional stress, and eating disorders.
RESUMO
BACKGROUND: Ulotaront (SEP-363856) is a novel agonist at trace amine-associated receptor 1 and serotonin 5-HT1A receptors in clinical development for the treatment of schizophrenia. Previous studies demonstrated ulotaront suppresses rapid eye movement (REM) sleep in both rodents and healthy volunteers. We assessed acute and sustained treatments of ulotaront on REM sleep and symptoms of cataplexy and alertness in subjects with narcolepsy-cataplexy. METHODS: In a multicenter, double-blind, placebo-controlled, randomized, 3-way crossover study, ulotaront was evaluated in 16 adults with narcolepsy-cataplexy. Two oral doses of ulotaront (25 mg and 50 mg) were administered daily for 2 weeks and compared with matching placebo (6-treatment sequence, 3-period, 3-treatment). RESULTS: Acute treatment with both 25 mg and 50 mg of ulotaront reduced minutes spent in nighttime REM compared to placebo. A sustained 2-week administration of both doses of ulotaront reduced the mean number of short-onset REM periods (SOREMPs) during daytime multiple sleep latency test (MSLT) compared to placebo. Although cataplexy events decreased from the overall mean baseline during the 2-week treatment period, neither dose of ulotaront statistically separated from placebo (p = 0.76, 25 mg; p = 0.82, 50 mg), and no significant improvement in patient and clinician measures of sleepiness from baseline to end of the 2-week treatment period occurred in any treatment group. CONCLUSIONS: Acute and sustained treatment with ulotaront reduced nighttime REM duration and daytime SOREMPs, respectively. The effect of ulotaront on suppression of REM did not demonstrate a statistical or clinically meaningful effect in narcolepsy-cataplexy. REGISTRATION: ClinicalTrials.gov identifier: NCT05015673.
Assuntos
Cataplexia , Narcolepsia , Humanos , Cataplexia/tratamento farmacológico , Cataplexia/diagnóstico , Estudos Cross-Over , Narcolepsia/tratamento farmacológico , Narcolepsia/diagnóstico , Piranos/uso terapêutico , AdultoRESUMO
Alzheimer's disease (AD) is the most common cause of dementia, accounting for more than 50 million patients worldwide. Current evidence suggests the exact mechanism behind this devastating disease to be of multifactorial origin, which seriously complicates the quest for an effective disease-modifying therapy, as well as impedes the search for strategic preventative measures. Of interest, preclinical studies point to serotonergic alterations, either induced via selective serotonin reuptake inhibitors or serotonin receptor (ant)agonists, in mitigating AD brain neuropathology next to its clinical symptoms, the latter being supported by a handful of human intervention trials. Additionally, a substantial amount of preclinical trials highlight the potential of diet, fecal microbiota transplantations, as well as pre- and probiotics in modulating the brain's serotonergic neurotransmitter system, starting from the gut. Whether such interventions could truly prevent, reverse or slow down AD progression likewise, should be initially tested in preclinical studies with AD mouse models, including sufficient analytical measurements both in gut and brain. Thereafter, its potential therapeutic effect could be confirmed in rigorously randomized controlled trials in humans, preferentially across the Alzheimer's continuum, but especially from the prodromal up to the mild stages, where both high adherence to such therapies, as well as sufficient room for noticeable enhancement are feasible still. In the end, such studies might aid in the development of a comprehensive approach to tackle this complex multifactorial disease, since serotonin and its derivatives across the microbiota-gut-brain axis might serve as possible biomarkers of disease progression, next to forming a valuable target in AD drug development. In this narrative review, the available evidence concerning the orchestrating role of serotonin within the microbiota-gut-brain axis in the development of AD is summarized and discussed, and general considerations for future studies are highlighted.
Assuntos
Doença de Alzheimer , Microbioma Gastrointestinal , Doença de Alzheimer/patologia , Animais , Encéfalo/patologia , Eixo Encéfalo-Intestino , Humanos , Camundongos , SerotoninaRESUMO
Silent angina is a critical phenomenon in the clinic and is more commonly associated with women patients suffering from myocardial ischemia. Its underlying cause remains mysterious in medicine. With our recent discovery of female-specific Ah-type baroreceptor neurons (BRNs), we hypothesize that cardiac analgesia is due to the direct activation of Ah-type BRNs by elevated levels of circulating serotonin (5-HT) myocardial infarction (MI) patients. Electromyography and the tail-flick reflex were assessed in control and MI-model rats to evaluate 5-HT-mediated BP regulation as well as peripheral and cardiac nociception. 5-HT or a 5-HT receptor agonist was microinjected into the nodose ganglion to confirm the involvement of the afferent pathway of the baroreflex arc. An inward current was observed in identified BRNs by applying a whole-cell patch-clamp technique in conjunction with qRT-PCR to verify the afferent-specific action of 5-HT and the expression of 5-HT receptors. Although the tail-flick reflex and mean arterial pressure were dramatically reduced in female MI rats with elevated serum 5-HT, intrapericardial capsaicin-evoked muscular discharges were significantly inhibited in comparing with those of males, which were mimicked by microinjection of 5-HT or SR57227A into the nodose. Ah-type BRNs displayed robust inward currents at lower concentrations of 5-HT than the C-type or the A-type, with significantly increased expression and cellular distribution of 5-HT3AR but not 5-HT3BR compared to the A- and C-types. Activation of 5-HT3AR in Ah-type BRNs by 5-HT contributes significantly to cardiac analgesia, which may suggest the pathogenic condition that silent angina occurs mainly in female patients.
Assuntos
Angina Pectoris/metabolismo , Pressão Sanguínea/fisiologia , Infarto do Miocárdio/metabolismo , Nociceptividade/fisiologia , Pressorreceptores/metabolismo , Serotonina/metabolismo , Animais , Barorreflexo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Gânglio Nodoso/efeitos dos fármacos , Gânglio Nodoso/metabolismo , Ratos , Receptores de Serotonina/metabolismo , Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologiaRESUMO
INTRODUCTION: Migraine is a neurovascular disorder. Current acute specific antimigraine pharmacotherapies target trigeminovascular 5-HT1B/1D, 5-HT1F and CGRP receptors but, unfortunately, they induce some cardiovascular and central side effects that lead to poor treatment adherence/compliance. Therefore, new antimigraine drugs are being explored. Areas covered: This review considers the adverse (or potential) side effects produced by current and prospective antimigraine drugs, including medication overuse headache (MOH) produced by ergots and triptans, the side effects observed in clinical trials for the new gepants and CGRP antibodies, and a section discussing the potential effects resulting from disruption of the cardiovascular CGRPergic neurotransmission. Expert opinion: The last decades have witnessed remarkable developments in antimigraine therapy, which includes acute (e.g. triptans) and prophylactic (e.g. ß-adrenoceptor blockers) antimigraine drugs. Indeed, the triptans represent a considerable advance, but their side effects (including nausea, dizziness and coronary vasoconstriction) preclude some patients from using triptans. This has led to the development of the ditans (5-HT1F receptor agonists), the gepants (CGRP receptor antagonists) and the monoclonal antibodies against CGRP or its receptor. The latter drugs represent a new hope in the antimigraine armamentarium, but as CGRP plays a role in cardiovascular homeostasis, the potential for adverse cardiovascular side effects remains latent.
Assuntos
Desenho de Fármacos , Transtornos de Enxaqueca/tratamento farmacológico , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacologia , Antagonistas do Receptor do Peptídeo Relacionado ao Gene de Calcitonina , Transtornos da Cefaleia Secundários/etiologia , Humanos , Transtornos de Enxaqueca/fisiopatologia , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , Receptores de Serotonina/efeitos dos fármacos , Receptores de Serotonina/metabolismo , Agonistas do Receptor de Serotonina/administração & dosagem , Agonistas do Receptor de Serotonina/efeitos adversos , Agonistas do Receptor de Serotonina/farmacologia , Triptaminas/administração & dosagem , Triptaminas/efeitos adversos , Triptaminas/farmacologia , Receptor 5-HT1F de SerotoninaRESUMO
Serotonin (5-HT) is an important neurotransmitter and paracrine signaling molecule in the gastrointestinal tract. Two distinct tryptophan hydroxylases (TPH), TPH1 and TPH2, are the rate-limiting enzymes in the 5-HT biosynthesis process. TPH1 expression is mainly limited in the enterochromaffin cells and distributed in peripheries such as the skin and gut, while TPH2 is the predominant isoform in the CNS. In this study, mol002291 was screened as a drug-like compound from the TCM database for the inhibitor of TPH. After the enzymological analysis of mol002291, the analgesic effect of mol002291 was also further investigated in a PI-IBS visceral hyperalgesia rat model. Results from kinetic analysis showed that mol002291 specifically inhibited the TPH1 but did not act on TPH2, and the inhibitory action displayed characteristics of competitive inhibition. In addition, the results from abdominal withdrawal reflex (AWR) tests and electromyography (EMG) recordings showed that mol002291 significantly (p < .05) alleviated the visceral hyperalgesia. This result is entirely consistent with the fact that mol002291 significantly decreased the 5-HT content. These data demonstrated that mol002291 can attenuate visceral hyperalgesia mediated via reducing colonic 5-HT content. More important is that mol002291 could be developed as a novel prodrug and offer therapeutic avenues for the diseases where there is dysregulation of peripheral serotonergic pathways.
Assuntos
Analgésicos/química , Desenho de Fármacos , Inibidores Enzimáticos/química , Pró-Fármacos/química , Triptofano Hidroxilase/antagonistas & inibidores , Analgésicos/metabolismo , Analgésicos/uso terapêutico , Animais , Sítios de Ligação , Domínio Catalítico , Bases de Dados Factuais , Eletromiografia , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/uso terapêutico , Humanos , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Hiperalgesia/patologia , Cinética , Masculino , Simulação de Acoplamento Molecular , Pró-Fármacos/metabolismo , Pró-Fármacos/uso terapêutico , Ratos , Ratos Sprague-Dawley , Serotonina/metabolismo , Triptofano Hidroxilase/metabolismoRESUMO
Rationale: The mechanisms responsible for the unique antidepressant properties of ketamine have only been partly resolved. Recent preclinical reports implicate the neurotransmitter serotonin [5-hydroxytryptamine (5-HT)] in the antidepressant-like response of ketamine, and modulation of 5-HT1B receptors has been hypothesized to attain an important role. Objectives: To evaluate the role of endogenous stimulation of 5-HT1B heteroreceptors in the antidepressant-like activity of S-ketamine. Method: Flinders sensitive line (FSL) rats, a genetic model of depression, were depleted of endogenous 5-HT by 4-chloro-DL-phenylalanine methyl ester HCl administration (pCPA; 86 mg/kg/day for 3 days). In pCPA-pretreated and control FSL rats, the acute and sustained effects of a single dose of S-ketamine (15 mg/kg) and the selective 5-HT1B receptor agonist CP94253 (1-6 mg/kg) alone and in combination with S-ketamine were studied in the forced swim test (FST), a commonly used assay that detects antidepressant activity. Results: pCPA pretreatment decreased cortical 5-HT levels to â¼6% but did not affect the baseline behavioral phenotype of FSL rats. S-ketamine demonstrated acute and sustained antidepressant-like activity, both of which were abolished by 5-HT depletion. Combining S-ketamine with a sub-effective dose of CP94253 (1 mg/kg) rescued S-ketamine's acute and sustained antidepressant-like effects, when CP94253 was administered 2 h prior to the FST. Co-administration of S-ketamine and CP94253 did not affect the plasma level of either compound, suggesting that the observed behavioral interaction could not be ascribed to a kinetic drug-drug interaction. Conclusion: 5-HT1B receptor activation during testing appears to be critical for S-ketamine's antidepressant-like potentials in this model.
RESUMO
A growing body of evidence suggests that our diet is an important contributing factor in the development, management and prevention of a number of psychiatric illnesses. Tryptophan, an essential amino acid, is the sole precursor of neurotransmitter 5-hydroxytryptamine (5-HT; serotonin). Administration of tryptophan can boost serotonin neurotransmission to produce therapeutically important effects in serotonin deficiency disorders. Anorexia nervosa (AN) an eating disorder associated with high levels of psychiatric comorbidity including psychosis, hyperactivity, depression and anxiety has highest lethality of all psychiatric illnesses. Evidence suggests that excessive dieting and food restriction can decrease brain tryptophan and serotonin in AN patients to precipitate depression, psychosis and hyperactivity. There are currently no FDA approved pharmacological treatments available for AN patients; antidepressants and antipsychotics, largely used to treat associated psychiatric comorbidities are also not very effective. The aim of this non-systematic review article is to evaluate and document a potential importance of tryptophan supplementation in improving therapeutics in AN patients.
Assuntos
Anorexia Nervosa/tratamento farmacológico , Serotonina/metabolismo , Triptofano/administração & dosagem , Animais , Anorexia Nervosa/fisiopatologia , Anorexia Nervosa/psicologia , Encéfalo/metabolismo , Dieta/psicologia , Suplementos Nutricionais , Humanos , Triptofano/metabolismoRESUMO
RATIONALE: For several decades, elite athletes and a growing number of recreational consumers have used anabolic androgenic steroids (AAS) as performance enhancing drugs. Despite mounting evidence that illicit use of these synthetic steroids has detrimental effects on affective states, information available on sex-specific actions of these drugs is lacking. OBJECTIVES: The focus of this review is to assess information to date on the importance of sex and its interaction with other environmental factors on affective behaviors, with an emphasis on data derived from non-human studies. METHODS: The PubMed database was searched for relevant studies in both sexes. RESULTS: Studies examining AAS use in females are limited, reflecting the lower prevalence of use in this sex. Data, however, indicate significant sex-specific differences in AAS effects on anxiety-like and aggressive behaviors, interactions with other drugs of abuse, and the interplay of AAS with other environmental factors such as diet and exercise. CONCLUSIONS: Current methods for assessing AAS use have limitations that suggest biases of both under- and over-reporting, which may be amplified for females who are poorly represented in self-report studies of human subjects and are rarely used in animal studies. Data from animal literature suggest that there are significant sex-specific differences in the impact of AAS on aggression, anxiety, and concomitant use of other abused substances. These results have relevance for human females who take these drugs as performance-enhancing substances and for transgender XX individuals who may illicitly self-administer AAS as they transition to a male gender identity.
Assuntos
Anabolizantes/efeitos adversos , Androgênios/efeitos adversos , Transtornos do Humor/induzido quimicamente , Transtornos do Humor/psicologia , Caracteres Sexuais , Agressão/efeitos dos fármacos , Agressão/psicologia , Anabolizantes/administração & dosagem , Androgênios/administração & dosagem , Animais , Ansiedade/induzido quimicamente , Ansiedade/psicologia , Feminino , Humanos , Masculino , Autoadministração , Esteroides/administração & dosagem , Esteroides/efeitos adversos , Resultado do TratamentoRESUMO
One of the most striking discoveries in the treatment of major depression was the finding that infusion of a single sub-anesthetic dose of ketamine induces rapid and sustained antidepressant effects in treatment-resistant depressed patients. However, ketamine's antidepressant-like actions are transient and can only be sustained by repeated drug treatment. Despite the fact that women experience major depression at roughly twice the rate of men, research regarding the neurobiological antidepressant-relevant effects of ketamine has focused almost exclusively on the male sex. Importantly, knowledge regarding the sex-differentiated effects, the frequency and the dose on which repeated ketamine administration stops being beneficial, is limited. In the current study, we investigated the behavioral, neurochemical and synaptic molecular effects of repeated ketamine treatment (10mg/kg; 21days) in male and female C57BL/6J mice. We report that ketamine induced beneficial antidepressant-like effects in male mice, but induced both anxiety-like (i.e., decreased time spent in the center of the open field arena) and depressive-like effects (i.e., enhanced immobility duration in the forced swim test; FST) in their female counterparts. Moreover, repeated ketamine treatment induced sustained sex-differentiated neurochemical and molecular effects, as it enhanced hippocampal synapsin protein levels and serotonin turnover in males, but attenuated glutamate and aspartate levels in female mice. Taken together, our findings indicate that repeated ketamine treatment induces opposite behavioral effects in male and female mice, and thus, present data have far-reaching implications for the sex-oriented use of ketamine in both experimental and clinical research settings.
Assuntos
Antidepressivos/administração & dosagem , Ansiedade/induzido quimicamente , Depressão/induzido quimicamente , Hipocampo/metabolismo , Ketamina/administração & dosagem , Caracteres Sexuais , Animais , Ácido Aspártico/metabolismo , Feminino , Ácido Glutâmico/metabolismo , Hipocampo/química , Ácido Hidroxi-Indolacético/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas SNARE/metabolismo , Serotonina/metabolismo , Sinapsinas/metabolismo , Sintaxina 1/metabolismoRESUMO
BACKGROUND: Radiotherapy-induced nausea and vomiting (RINV) is a toxicity that can occur in 40-80% of individuals who receive radiation treatment. Current guidelines recommend 5-hydroxytryptamine3 receptor antagonists (5-HT3 RAs) for prophylaxis of RINV for moderate and highly emetogenic radiotherapy; however, certain patients may suffer from RINV despite prophylaxis. CASE PRESENTATION: This report details the case of a 47-year-old female with extensive bony involvement to the spine from breast cancer presenting with lower back pain. CASE MANAGEMENT: To palliate her symptoms, the patient underwent a course of irradiation to the lumbar spine and was prescribed ondansetron as an antiemetic. However, the patient experienced severe nausea and emesis and was subsequently switched to granisetron and aprepitant. CASE OUTCOME: The patient completed the remainder of the radiation treatment with no further emesis and minimal nausea, representing the first documented success of granisetron and aprepitant for RINV after failure on ondansetron. CONCLUSIONS: In chemotherapy, switching 5-HT3 RAs after failure on the first is successful in preventing chemotherapy-induced nausea and vomiting (CINV), yet this has not been previously reported in radiation. In this patient, granisetron and aprepitant were successful in substantially reducing nausea and preventing further emesis, and may represent an alternative antiemetic regimen for RINV prophylaxis and salvage.
Assuntos
Antieméticos/administração & dosagem , Neoplasias Ósseas/radioterapia , Neoplasias da Mama/patologia , Náusea/prevenção & controle , Aprepitanto , Neoplasias Ósseas/secundário , Feminino , Granisetron/administração & dosagem , Humanos , Pessoa de Meia-Idade , Morfolinas/administração & dosagem , Náusea/etiologia , Metástase Neoplásica , Ondansetron/administração & dosagemRESUMO
Gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN), considered a heterogeneous neoplasia, exhibit ill-defined pathobiology and protean symptomatology and are ubiquitous in location. They are difficult to diagnose, challenging to manage, and outcome depends on cell type, secretory product, histopathologic grading, and organ of origin. A morphologic and molecular genomic review of these lesions highlights tumor characteristics that can be used clinically, such as somatostatin-receptor expression, and confirms features that set them outside the standard neoplasia paradigm. Their unique pathobiology is useful for developing diagnostics using somatostatin-receptor targeted imaging or uptake of radiolabeled amino acids specific to secretory products or metabolism. Therapy has evolved via targeting of protein kinase B signaling or somatostatin receptors with drugs or isotopes (peptide-receptor radiotherapy). With DNA sequencing, rarely identified activating mutations confirm that tumor suppressor genes are relevant. Genomic approaches focusing on cancer-associated genes and signaling pathways likely will remain uninformative. Their uniquely dissimilar molecular profiles mean individual tumors are unlikely to be easily or uniformly targeted by therapeutics currently linked to standard cancer genetic paradigms. The prevalence of menin mutations in pancreatic NEN and P27KIP1 mutations in small intestinal NEN represents initial steps to identifying a regulatory commonality in GEP-NEN. Transcriptional profiling and network-based analyses may define the cellular toolkit. Multianalyte diagnostic tools facilitate more accurate molecular pathologic delineations of NEN for assessing prognosis and identifying strategies for individualized patient treatment. GEP-NEN remain unique, poorly understood entities, and insight into their pathobiology and molecular mechanisms of growth and metastasis will help identify the diagnostic and therapeutic weaknesses of this neoplasia.
RESUMO
Altered serotonin (5-hydroxytryptamine, 5-HT) signaling has been implicated in some developmental abnormalities of autism spectrum disorder (ASD). However, the presumed role of 5-HT in ASD raises new questions in fundamental neuroscience. Specifically, it is not clear if the current piecemeal approach to 5-HT signaling in the mammalian body is effective and whether new conceptual approaches may be required. This review briefly discusses 5-HT production and circulation in the central nervous system and outside of it, especially with regard to ASD, and proposes a more encompassing approach that questions the utility of the "neurotransmitter" concept. It then introduces the idea of a generalized 5-HT packet that may offer insights into possible links between serotonergic varicosities and blood platelets. These approaches have theoretical significance, but they are also well positioned to advance our understanding of some long-standing problems in autism research.