Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.886
Filtrar
1.
J Phys Chem B ; 126(35): 6682-6690, 2022 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-35973070

RESUMO

G protein-coupled receptors (GPCRs) are signaling hubs in cell membranes that regulate a wide range of physiological processes and are popular drug targets. Serotonin1A receptors are important members of the GPCR family and are implicated in neuropsychiatric disorders. Cholesterol is a key constituent of higher eukaryotic membranes and is believed to contribute to the segregated distribution of membrane constituents into domains. To explore the role of cholesterol in lateral dynamics of GPCRs, we utilized single particle tracking (SPT) to monitor diffusion of serotonin1A receptors under acute and chronic cholesterol-depleted conditions. Our results show that the short-term diffusion coefficient of the receptor decreases upon cholesterol depletion, irrespective of the method of cholesterol depletion. Analysis of SPT trajectories revealed that relative populations of receptors undergoing various modes of diffusion change upon cholesterol depletion. Notably, in cholesterol-depleted cells, we observed an increase in the confined population of the receptor accompanied by a reduction in diffusion coefficient for chronic cholesterol depletion. These results are supported by our recent work and present observations that show polymerization of G-actin in response to chronic cholesterol depletion. Taken together, our results bring out the interdependence of cholesterol and actin cytoskeleton in regulating diffusion of GPCRs in membranes.


Assuntos
Receptor 5-HT1A de Serotonina , Serotonina , Membrana Celular/metabolismo , Colesterol/metabolismo , Difusão , Receptor 5-HT1A de Serotonina/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Serotonina/metabolismo , Imagem Individual de Molécula
2.
J Membr Biol ; 255(6): 739-746, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35986776

RESUMO

G protein-coupled receptors (GPCRs) constitute the largest class of membrane proteins that transduce signals across the plasma membrane and orchestrate a multitude of physiological processes within cells. The serotonin1A receptor is a crucial neurotransmitter receptor in the GPCR family involved in a multitude of neurological, behavioral and cognitive functions. We have previously shown, using a combination of experimental and simulation approaches, that membrane cholesterol acts as a key regulator of organization, dynamics, signaling and endocytosis of the serotonin1A receptor. In addition, we showed that membrane cholesterol stabilizes the serotonin1A receptor against thermal deactivation. In the present work, we explored the molecular basis of cholesterol-induced thermal stability of the serotonin1A receptor. For this, we explored the possible role of the K101 residue in a cholesterol recognition/interaction amino acid consensus (CRAC) motif in transmembrane helix 2 in conferring the thermal stability of the serotonin1A receptor. Our results show that a mutation in the K101 residue leads to loss in thermal stability of the serotonin1A receptor imparted by cholesterol, independent of membrane cholesterol content. We envision that our results could have potential implications in structural biological advancements of GPCRs and design of thermally stabilized receptors for drug development.


Assuntos
Lisina , Serotonina , Serotonina/análise , Serotonina/metabolismo , Receptor 5-HT1A de Serotonina/genética , Receptor 5-HT1A de Serotonina/metabolismo , Colesterol/química , Membrana Celular/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
3.
Int J Mol Sci ; 23(13)2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35806448

RESUMO

Some diseases that are associated with dopamine deficiency are accompanied by psychiatric symptoms, including Parkinson's disease. However, the mechanism by which this occurs has not been clarified. Previous studies found that dopamine-deficient (DD) mice exhibited hyperactivity in a novel environment. This hyperactivity is improved by clozapine and donepezil, which are used to treat psychiatric symptoms associated with dopamine deficiency (PSDD). We considered that DD mice could be used to study PSDD. In the present study, we sought to identify the pharmacological mechanism of PSDD. We conducted locomotor activity tests by administering quetiapine and drugs that have specific actions on serotonin (5-hydroxytryptamine [5-HT]) receptors and muscarinic receptors. Changes in neuronal activity that were induced by drug administration in DD mice were evaluated by examining Fos immunoreactivity. Quetiapine suppressed hyperactivity in DD mice while the 5-HT1A receptor antagonist WAY100635 inhibited this effect. The number of Fos-positive neurons in the median raphe nucleus increased in DD mice that exhibited hyperactivity and was decreased by treatment with quetiapine and 5-HT1A receptor agonists. In conclusion, hyperactivity in DD mice was ameliorated by quetiapine, likely through 5-HT1A receptor activation. These findings suggest that 5-HT1A receptors may play a role in PSDD, and 5-HT1A receptor-targeting drugs may help improve PSDD.


Assuntos
Antipsicóticos , Dopamina , Fumarato de Quetiapina , Receptor 5-HT1A de Serotonina , Agonistas do Receptor 5-HT1 de Serotonina , Animais , Antipsicóticos/farmacologia , Dopamina/deficiência , Dopamina/metabolismo , Camundongos , Fumarato de Quetiapina/farmacologia , Receptor 5-HT1A de Serotonina/metabolismo , Serotonina/metabolismo , Agonistas do Receptor 5-HT1 de Serotonina/farmacologia , Antagonistas da Serotonina/farmacologia
4.
ACS Chem Neurosci ; 13(14): 2078-2083, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35802379

RESUMO

The serotonin 1A (5-HT1A) receptor is a G-protein-coupled receptor implicated in the pathophysiology of several neuropsychiatric and neurodegenerative disorders. We here report the preparation of two candidate 5-HT1A radioligands, [11C]AZ11132132 ([11C]3) and [11C]AZ11895530 ([11C]4), and their subsequent evaluation in vitro using autoradiography and in vivo using positron emission tomography (PET). Compounds 3 and 4 were radiolabeled at high radiochemical purity (>99%) and high molar activity (>38 GBq/µmol) by heteroatom methylation with [11C]methyl iodide. Autoradiography on whole hemispheres from post-mortem human brain revealed substantial nonspecific binding of [11C]3, while the binding of [11C]4 to brain tissue was consistent with the distribution of 5-HT1A receptors and sensitive to co-incubation with the reference 5-HT1A antagonist WAY-100635 (10 µM). Following intravenous injection of [11C]4 into a cynomolgus monkey, brain radioactivity concentration (Cmax ∼ 2.2 SUV) was high whereafter it decreased rapidly. The regional binding potential (BPND) values were calculated using the simplified reference tissue model with cerebellum as reference region. The values varied between 0.2 and 1.0 for temporal cortex, raphe nuclei, frontal cortex, and hippocampus which is consistent with the known 5-HT1A expression pattern. After pretreatment with WAY100635 (0.5 mg/kg), a homogeneous distribution of radioactivity was observed in non-human primate (NHP) brain. Although [11C]4 fulfilled important criteria for successful in vivo neuroimaging, including good blood-brain-barrier permeability and high specific binding in vitro to human brain tissue, the regional BPND values for [11C]4 in NHP brain were low when compared to those obtained with existing radioligands and thus do not merit further investigation of [11C]4. Evaluation of structurally related analogues is underway in our laboratory to identify improved candidates for clinical imaging.


Assuntos
Receptor 5-HT1A de Serotonina , Serotonina , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Macaca fascicularis/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Receptor 5-HT1A de Serotonina/metabolismo , Serotonina/metabolismo , Tomografia Computadorizada por Raios X
5.
Hepatol Commun ; 6(11): 3194-3211, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35894804

RESUMO

The tumor microenvironment (TME) is considered to be one of the vital mediators of tumor progression. Extracellular matrix (ECM), infiltrating immune cells, and stromal cells collectively constitute the complex ecosystem with varied biochemical and biophysical properties. The development of liver cancer is strongly tied with fibrosis and cirrhosis that alters the microenvironmental landscape, especially ECM composition. Enhanced deposition and cross-linking of type I collagen are frequently detected in patients with liver cancer and have been shown to facilitate tumor growth and metastasis by epithelial-to-mesenchymal transition. However, information on the effect of collagen enrichment on drug resistance is lacking. Thus, the present study has comprehensively illustrated phenotypical and mechanistic changes in an in vitro mimicry of collagen-enriched TME and revealed that collagen enrichment could induce 5-fluorouracil (5FU) and sorafenib resistance in liver cancer cells through hypoxia-induced up-regulation of lysyl oxidase-like 2 (LOXL2). LOXL2, an enzyme that facilitates collagen cross-linking, enhances cell adhesion-mediated drug resistance by activating the integrin alpha 5 (ITGA5)/focal adhesion kinase (FAK)/phosphoinositide 3-kinase (PI3K)/rho-associated kinase 1 (ROCK1) signaling axis. Conclusion: We demonstrated that inhibition of LOXL2 in a collagen-enriched microenvironment synergistically promotes the efficacy of sorafenib and 5FU through deterioration of focal adhesion signaling. These findings have clinical implications for developing LOXL2-targeted strategies in patients with chemoresistant liver cancer and especially for those patients with advanced fibrosis and cirrhosis.


Assuntos
Neoplasias Hepáticas , Microambiente Tumoral , Humanos , Aminoácido Oxirredutases/metabolismo , Colágeno/metabolismo , Colágeno Tipo I , Resistência a Medicamentos , Ecossistema , Fluoruracila/farmacologia , Integrinas , Cirrose Hepática/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Fosfatidilinositol 3-Quinase , Fosfatidilinositol 3-Quinases , Proteína-Lisina 6-Oxidase , Quinases Associadas a rho , Sorafenibe , Receptor 5-HT1A de Serotonina/metabolismo
6.
Biomolecules ; 12(6)2022 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-35740874

RESUMO

Targeted therapy uses multiple ways of ensuring that the drug will be delivered to the desired site. One of these ways is an encapsulation of the drug and functionalization of the surface. Among the many molecules that can perform such a task, the present work focused on the antibodies of single-chain variable fragments (scFvs format). We studied scFv, which specifically recognizes the dopamine D2 and serotonin 5-HT1A receptor heteromers. The scFvD2-5-HT1A protein was analyzed biochemically and biologically, and the obtained results indicated that the antibody is properly folded and non-toxic and can be described as low-immunogenic. It is not only able to bind to the D2-5-HT1A receptor heteromer, but it also influences the cAMP signaling pathway and-when surfaced on nanogold particles-it can cross the blood-brain barrier in in vitro models. When administered to mice, it decreased locomotor activity, matching the effect induced by clozapine. Thus, we are strongly convinced that scFvD2-5-HT1A, which was a subject of the present investigation, is a promising targeting ligand with the potential for the functionalization of nanocarriers targeting selected areas of the brain.


Assuntos
Antipsicóticos , Portadores de Fármacos , Receptor 5-HT1A de Serotonina , Receptores de Dopamina D2 , Anticorpos de Cadeia Única , Animais , Antipsicóticos/farmacologia , Encéfalo/metabolismo , Dopamina/metabolismo , Ligantes , Camundongos , Receptor 5-HT1A de Serotonina/metabolismo , Receptores de Dopamina D2/metabolismo
7.
Langmuir ; 38(22): 6798-6807, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35608952

RESUMO

Lipid oxidation has significant effects on lipid bilayer properties; these effects can be expected to extend to interactions between the lipid bilayer and integral membrane proteins. Given that G protein-coupled receptor (GPCR) activity is known to depend on the properties of the surrounding lipid bilayer, these proteins represent an intriguing class of molecules in which the impact of lipid oxidation on protein behavior is studied. Here, we study the effects of lipid oxidation on the human serotonin 1A receptor (5-HT1AR). Giant unilamellar vesicles (GUVs) containing integral 5-HT1AR were fabricated by the hydrogel swelling method; these GUVs contained polyunsaturated 1-palmitoyl-2-linoleoyl-sn-glycero-3-phosphocholine (PLinPC) and its oxidation product 1-palmitoyl-2-(9'-oxo-nonanoyl)-sn-glycero-3-phosphocholine (PoxnoPC) at various ratios. 5-HT1AR-integrated GUVs were also fabricated from lipid mixtures that had been oxidized by extended exposure to the atmosphere. Both types of vesicles were used to evaluate 5-HT1AR activity using an assay to quantify GDP-GTP exchange by the coupled G protein α subunit. Results indicated that 5-HT1AR activity increases significantly in bilayers containing oxidized lipids. This work is an important step in understanding how hyperbaric oxidation can change plasma membrane properties and lead to physiological dysfunction.


Assuntos
Bicamadas Lipídicas , Lipídeos de Membrana , Receptor 5-HT1A de Serotonina , Humanos , Bicamadas Lipídicas/metabolismo , Metabolismo dos Lipídeos/fisiologia , Lipídeos de Membrana/metabolismo , Oxirredução , Fosfatidilcolinas , Receptor 5-HT1A de Serotonina/metabolismo , Serotonina , Lipossomas Unilamelares/síntese química
8.
Synapse ; 76(7-8): e22235, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35587913

RESUMO

Decreased 5-HT1A receptor binding has been associated with Alzheimer's disease (AD) and interpreted as a consequence of neuron loss. The purpose of the present study was to compare [11 C]WAY100635 binding to the 5-HT1A receptor in the hippocampus, entorhinal cortex, amygdala and pericalcarine cortex in mild AD patients and elderly controls. AD patients (n = 7) and elderly control subjects (n = 8) were examined with positron emission tomography (PET) and [11 C]WAY100635. PET data acquisition was performed with an ECAT EXACT HR system. Wavelet-aided parametric images of nondisplaceable binding potential (BPND ) were generated using Logan's graphical analysis with cerebellum as the reference region. Correction for partial volume effects was performed with the Müller-Gärtner method. Regions of interest (ROIs) were applied to the individual parametric images, and the regional BPND was calculated as the average parametric voxel value within each ROI. In addition to comparisons between subject groups, correlations between BPND values and scores on the Mini-Mental State Examination, Disability Assessment for Dementia (DAD), and Neuropsychiatric Inventory were expressed by Pearson correlation coefficients. Mean regional BPND was lower in AD patients than in control subjects, and the difference was statistically significant for the hippocampus, entorhinal cortex, and amygdala. A statistically significant correlation was obtained between hippocampal BPND values and DAD scores. The results of the present study corroborate and extend previous findings of decreased 5-HT1A binding in AD and strengthen the support for 5-HT1A receptor PET as a tool for the assessment of neurodegenerative changes in mild AD.


Assuntos
Doença de Alzheimer , Idoso , Doença de Alzheimer/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Córtex Entorrinal/metabolismo , Humanos , Tomografia por Emissão de Pósitrons/métodos , Receptor 5-HT1A de Serotonina/metabolismo , Serotonina/metabolismo
9.
Molecules ; 27(7)2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35408749

RESUMO

The importance of the dynamic interplay between the opioid and the serotonin neuromodulatory systems in chronic pain is well recognized. In this study, we investigated whether these two signalling pathways can be integrated at the single-cell level via direct interactions between the mu-opioid (MOP) and the serotonin 1A (5-HT1A) receptors. Using fluorescence cross-correlation spectroscopy (FCCS), a quantitative method with single-molecule sensitivity, we characterized in live cells MOP and 5-HT1A interactions and the effects of prolonged (18 h) exposure to selected non-peptide opioids: morphine, codeine, oxycodone and fentanyl, on the extent of these interactions. The results indicate that in the plasma membrane, MOP and 5-HT1A receptors form heterodimers that are characterized with an apparent dissociation constant Kdapp = (440 ± 70) nM). Prolonged exposure to all non-peptide opioids tested facilitated MOP and 5-HT1A heterodimerization and stabilized the heterodimer complexes, albeit to a different extent: Kd, Fentanylapp = (80 ± 70) nM), Kd,Morphineapp = (200 ± 70) nM, Kd, Codeineapp = (100 ± 70) nM and Kd, Oxycodoneapp = (200 ± 70) nM. The non-peptide opioids differed also in the extent to which they affected the mitogen-activated protein kinases (MAPKs) p38 and the extracellular signal-regulated kinase (Erk1/2), with morphine, codeine and fentanyl activating both pathways, whereas oxycodone activated p38 but not ERK1/2. Acute stimulation with different non-peptide opioids differently affected the intracellular Ca2+ levels and signalling dynamics. Hypothetically, targeting MOP-5-HT1A heterodimer formation could become a new strategy to counteract opioid induced hyperalgesia and help to preserve the analgesic effects of opioids in chronic pain.


Assuntos
Analgésicos Opioides , Dor Crônica , Receptores Opioides mu , Analgésicos Opioides/farmacologia , Codeína , Fentanila/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases , Morfina/farmacologia , Oxicodona , Receptor 5-HT1A de Serotonina/metabolismo , Receptores Opioides mu/metabolismo
10.
ACS Chem Neurosci ; 13(9): 1456-1466, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35467841

RESUMO

Cellular hypoxia causes numerous pathophysiological conditions associated with the disruption of oxygen homeostasis. Under oxygen-deficient conditions, cells adapt by controlling the cellular functions to facilitate the judicious use of available oxygen, such as cessation of cell growth and proliferation. In higher eukaryotes, the process of cholesterol biosynthesis is intimately coupled to the availability of oxygen, where the synthesis of one molecule of cholesterol requires 11 molecules of O2. Cholesterol is an essential component of higher eukaryotic membranes and is crucial for the physiological functions of several membrane proteins and receptors. The serotonin1A receptor, an important neurotransmitter G protein-coupled receptor associated with cognition and memory, has previously been shown to depend on cholesterol for its signaling and function. In this work, in order to explore the interdependence of oxygen levels, cholesterol biosynthesis, and the function of the serotonin1A receptor, we developed a cellular hypoxia model to explore the function of the human serotonin1A receptor heterologously expressed in Chinese hamster ovary cells. We observed cell cycle arrest at G1/S phase and the accumulation of lanosterol in cell membranes under hypoxic conditions, thereby validating our cellular model. Interestingly, we observed a significant reduction in ligand binding and disruption of downstream cAMP signaling of the serotonin1A receptor under hypoxic conditions. To the best of our knowledge, our results represent the first report linking the function of the serotonin1A receptor with hypoxia. From a broader perspective, these results contribute to our overall understanding of the molecular basis underlying neurological conditions often associated with hypoxia-induced brain dysfunction.


Assuntos
Receptor 5-HT1A de Serotonina/metabolismo , Serotonina , Animais , Células CHO , Hipóxia Celular , Colesterol/metabolismo , Cricetinae , Cricetulus , Humanos , Hipóxia , Oxigênio , Serotonina/metabolismo
11.
Pharm Res ; 39(5): 837-850, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35484370

RESUMO

PURPOSE: Ulotaront (SEP-363856) is a TAAR1 agonist with 5-HT1A agonist activity currently in clinical development for the treatment of schizophrenia. The objectives of the current study were to characterize the in vitro ADME properties, preclinical PK, and to evaluate the DDI potential of ulotaront and its major metabolite SEP-383103. METHODS: Solubility, permeability, plasma protein binding, CYP inhibition and induction, transporter inhibition and uptake studies were conducted in vitro. Phenotyping studies were conducted using recombinant human CYPs and FMOs, human liver microsomes and human liver homogenates. Preclinical plasma and brain pharmacokinetics were determined after a single intraperitoneal, intravenous, and oral administration of ulotaront. RESULTS: Ulotaront is a compound of high solubility, high permeability, and low binding to plasma proteins. Ulotaront metabolism is mediated via both NADPH-dependent and NADPH-independent pathways, with CYP2D6 as the major metabolizing enzyme. Ulotaront is an inducer of CYP2B6, and an inhibitor of CYP2D6, OCT1 and OCT2, while SEP-383103 is neither a CYP inducer nor a potent inhibitor of CYPs and human transporters. Ulotaront exhibits rapid absorption, greater than 70% bioavailability, approximately 3.5 L/kg volume of distribution, 1.5-4 h half-life, 12-43 ml/min/kg clearance, and good penetration across the blood-brain barrier in preclinical species. CONCLUSIONS: Ulotaront has been designated as a BCS1 compound by US FDA. The ability of ulotaront to penetrate the blood-brain barrier for CNS targeting has been demonstrated in mice and rats. The potential for ulotaront and SEP-383103 to act as perpetrators of CYP and transporter-mediated DDIs is predicted to be remote.


Assuntos
Receptor 5-HT1A de Serotonina , Esquizofrenia , Animais , Citocromo P-450 CYP2D6/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Camundongos , Microssomos Hepáticos/metabolismo , NADP/metabolismo , NADP/farmacologia , Preparações Farmacêuticas/metabolismo , Ratos , Receptor 5-HT1A de Serotonina/metabolismo , Esquizofrenia/tratamento farmacológico
12.
Respir Res ; 23(1): 42, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35241072

RESUMO

BACKGROUND: Intermittent hypoxia induces increased ventilatory responses in a 5-HT-dependent manner. This study aimed to explore that effect of raphe magnus serotonin 1A receptor (5-HT1A) receptor on the increased ventilatory responses induced by intermittent hypoxia. METHODS: Stereotaxic surgery was performed in adult male rats, and acute and chronic intermittent hypoxia models were established after recovery from surgery. The experimental group received microinjections of 5-HT1A receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) into the raphe magnus nucleus (RMg). Meanwhile, the control group received microinjections of artificial cerebrospinal fluid instead of 8-OH-DPAT. Ventilatory responses were compared among the different groups of oxygen status. 5-HT expressions in the RMg region were assessed by immunohistochemistry after chronic intermittent hypoxia. RESULTS: Compared with the normoxia group, the acute intermittent hypoxia group exhibited higher ventilatory responses (e.g., shorter inspiratory time and higher tidal volume, frequency of breathing, minute ventilation, and mean inspiratory flow) (P < 0.05). 8-OH-DPAT microinjection partly weakened these changes in the acute intermittent hypoxia group. Further, compared with the acute intermittent hypoxia group, rats in chronic intermittent hypoxia group exhibited higher measures of ventilatory responses after 1 day of intermittent hypoxia (P < 0.05). These effects peaked after 3 days of intermittent hypoxia treatment and then decreased gradually. Moreover, these changes were diminished in the experimental group. 5-HT expression in the RMg region increased after chronic intermittent hypoxia, which was consistent with the changing trend of ventilatory responses. While activation of the 5-HT1A receptor in the RMg region alleviated this phenomenon. CONCLUSIONS: The results indicate that RMg 5-HT1A receptor, via changing the expression level of 5-HT in the RMg region, is involved in the modulation of the increased ventilatory responses induced by intermittent hypoxia.


Assuntos
Hipóxia/metabolismo , Núcleo Magno da Rafe/metabolismo , Ventilação Pulmonar/efeitos dos fármacos , Receptor 5-HT1A de Serotonina/metabolismo , Agonistas do Receptor de Serotonina/farmacologia , Volume de Ventilação Pulmonar/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Hipóxia/tratamento farmacológico , Hipóxia/fisiopatologia , Masculino , Núcleo Magno da Rafe/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
13.
Brain Res ; 1783: 147859, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35245487

RESUMO

The ability to adapt to stress is an essential defensive function of a living body, and disturbance of this ability in the brain may contribute to the development of affective illness. Previously, we reported that mice exposed to unadaptable restraint stress show emotional abnormality. Moreover, this emotional abnormality was alleviated by chronic treatment with flesinoxan, a serotonin (5-HT)1A receptor agonist. 5-HT1A receptor expression is regulated by several transcription factors such as nuclear deformed epidermal autoregulatory factor (NUDR/Deaf-1) and five prime repressors under dual repression binding protein 1 (Freud-1). The present study was designed to investigate the expression levels of 5-HT1A receptor and its transcription factors in the midbrain and hippocampus of stress-adaptive and -unadaptive mice. Mice were exposed to 14 days of repeated adaptable (1 h/day) or repeated unadaptable (4 h/day) restraint stress, or were left in their home cage (non-stressed groups). In a western blot analysis, a significant increase in the expression levels of 5HT1A receptor protein were observed in the hippocampal membrane fraction in stress-adaptive mice. In contrast, the expression levels of 5-HT1A receptor protein in stress-unadaptive mice were significantly increased in both cytoplasmic and membrane fraction of the midbrain. Furthermore, real-time PCR analysis revealed that, in the midbrain of stress-unadaptive mice, the expression levels of 5-HT1A receptor mRNA and Freud-1 or NUDR mRNA were significantly increased and decreased, respectively. These results suggest that increased expression of 5-HT1A receptor due to decrease in the expression of Freud-1 and NUDR in the midbrain may play a pivotal role in the emotional abnormality of stress-unadaptive mice.


Assuntos
Receptor 5-HT1A de Serotonina , Fatores de Transcrição , Animais , Regulação da Expressão Gênica , Mesencéfalo/metabolismo , Camundongos , RNA Mensageiro/metabolismo , Receptor 5-HT1A de Serotonina/metabolismo , Receptores de Serotonina/metabolismo , Serotonina , Agonistas do Receptor de Serotonina , Fatores de Transcrição/metabolismo
14.
Transl Psychiatry ; 12(1): 122, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35338110

RESUMO

G protein-coupled receptor (GPCR) heterodimers are new targets for the treatment of depression. Increasing evidence supports the importance of serotonergic and orexin-producing neurons in numerous physiological processes, possibly via a crucial interaction between 5-hydroxytryptamine 1A receptor (5-HT1AR) and orexin receptor 1 (OX1R). However, little is known about the function of 5-HT1AR/OX1R heterodimers. It is unclear how the transmembrane domains (TMs) of the dimer affect its function and whether its modulation mediates antidepressant-like effects. Here, we examined the mechanism of 5-HT1AR/OX1R dimerization and downstream G protein-dependent signaling. We found that 5-HT1AR and OX1R form constitutive heterodimers that induce novel G protein-dependent signaling, and that this heterodimerization does not affect recruitment of ß-arrestins to the complex. In addition, we found that the structural interface of the active 5-HT1AR/OX1R dimer transforms from TM4/TM5 in the basal state to TM6 in the active conformation. We also used mutation analyses to identify key residues at the interface (5-HT1AR R1514.40, 5-HT1AR Y1985.41, and OX1R L2305.54). Injection of chronic unpredictable mild stress (CUMS) rats with TM4/TM5 peptides improved their depression-like emotional status and decreased the number of endogenous 5-HT1AR/OX1R heterodimers in the rat brain. These antidepressant effects may be mediated by upregulation of BDNF levels and enhanced phosphorylation and activation of CREB in the hippocampus and medial prefrontal cortex. This study provides evidence that 5-HT1AR/OX1R heterodimers are involved in the pathological process of depression. Peptides including TMs of the 5-HT1AR/OX1R heterodimer interface are candidates for the development of compounds with fast-acting antidepressant-like effects.


Assuntos
Receptor 5-HT1A de Serotonina , Animais , Antidepressivos , Depressão/genética , Depressão/metabolismo , Receptores de Orexina/genética , Fosforilação , Ratos , Receptor 5-HT1A de Serotonina/metabolismo , Transdução de Sinais/genética
15.
Adv Sci (Weinh) ; 9(12): e2105672, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35199941

RESUMO

Triple-negative breast cancer is the most aggressive subtype of breast cancer and the incidence of depression in breast cancer patients is high, which leading to worse survival and increased risk of recurrence. The effect of antidepressants on breast cancer patients remains contradictory, which might be due to variations in antidepression targets. Therefore, there is significant value to explore the antitumor potential of antidepressants and discover new therapeutic targets for breast patients. The authors screen antidepressant-related oncogenes or suppressors by using siRNAs. After combining functional experiments with online database analysis, 5-hydroxytryptamine receptor 1A (HTR1A is selected with antitumor potential in breast cancer cells in vivo and in vitro. RNA-seq analysis and coimmunoprecipitation assays indicate that HTR1A interacts with TRIM21 and PSMD7 to inhibit the degradation of TßRII through the ubiquitin-proteasome pathway, thereby inhibiting the transforming growth factor-ß (TGF-ß) canonical and noncanonical pathway. In addition, HTR1A is an independent predictive factor for breast cancer patients. The combined treatment of HTR1A agonists with demethylation drugs may significantly improve patient survival. It is of great significance to clarify the function and mechanism of the depression-related gene HTR1A in breast cancer, which might provide a new approach for triple-negative breast cancer patients.


Assuntos
Receptor 5-HT1A de Serotonina , Neoplasias de Mama Triplo Negativas , Humanos , Prognóstico , Receptor 5-HT1A de Serotonina/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
16.
Int J Mol Sci ; 23(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35216076

RESUMO

The neurotransmitter serotonin (5-HT) plays an important role in mood disorders. It has been demonstrated that 5-HT signaling through 5-HT1A receptors (5-HT1A-R) is crucial for early postnatal hippocampal development and later-life behavior. Although this suggests that 5-HT1A-R signaling regulates early brain development, the mechanistic underpinnings of this process have remained unclear. Here we show that stimulation of the 5-HT1A-R at postnatal day 6 (P6) by intrahippocampal infusion of the agonist 8-OH-DPAT (D) causes signaling through protein kinase Cε (PKCε) and extracellular receptor activated kinase ½ (ERK1/2) to boost neuroblast proliferation in the dentate gyrus (DG), as displayed by an increase in bromodeoxy-uridine (BrdU), doublecortin (DCX) double-positive cells. This boost in neuroproliferation was eliminated in mice treated with D in the presence of a 5-HT1A-R antagonist (WAY100635), a selective PKCε inhibitor, or an ERK1/2-kinase (MEK) inhibitor (U0126). It is believed that hippocampal neuro-progenitors undergoing neonatal proliferation subsequently become postmitotic and enter the synaptogenesis phase. Double-staining with antibodies against bromodeoxyuridine (BrdU) and neuronal nuclear protein (NeuN) confirmed that 5-HT1A-R → PKCε → ERK1/2-mediated boosted neuroproliferation at P6 also leads to an increase in BrdU-labeled granular neurons at P36. This 5-HT1A-R-mediated increase in mature neurons was unlikely due to suppressed apoptosis, because terminal deoxynucleotidyl transferase dUTP nick-end labeling analysis showed no difference in DNA terminal labeling between vehicle and 8-OH-DPAT-infused mice. Therefore, 5-HT1A-R signaling through PKCε may play an important role in micro-neurogenesis in the DG at P6, following which many of these new-born neuroprogenitors develop into mature neurons.


Assuntos
Hipocampo/metabolismo , Neurogênese/fisiologia , Proteína Quinase C-épsilon/metabolismo , Receptor 5-HT1A de Serotonina/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Serotonina/metabolismo , Transdução de Sinais/fisiologia , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Bromodesoxiuridina/farmacologia , Giro Denteado/efeitos dos fármacos , Giro Denteado/metabolismo , Giro Denteado/fisiologia , Feminino , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurogênese/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/fisiologia , Agonistas do Receptor de Serotonina/farmacologia , Transdução de Sinais/efeitos dos fármacos
17.
Neuroreport ; 33(3): 145-152, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35139062

RESUMO

OBJECTIVES: The existing anxiety animal models are susceptible to interference, and no single animal anxiety model can predict the future anxiolytic potential and profile of new putative anxiolytics. Therefore, to find a better anxiety animal model, we used FG7142, a nonselective benzodiazepine inverse agonist. This anxiety animal model was established by intraperitoneal injection of FG7142 combined with restraint stress. METHODS: Adult male C57BL/6J mice (18-20 g) were randomly classified into five groups (n = 10 per group), namely the control, restraint stress, restraint stress + 10 mg/kg FG7142, restraint stress + 20 mg/kg FG7142, restraint stress +30 mg/kg FG7142. The impact on behavior was explored by elevated plus maze, and marble burying test, followed by immunohistochemistry and quantitative real-time PCR enabled the elucidation of the possible mechanism. RESULTS: Compared with the control group and restraint stress group, intraperitoneal injection of FG7142 combined with restraint stress model group was found to induce anxiogenic-like behavior in elevated plus maze and marble burying test. Moreover, relative to the control group, significantly increased expression of c-fos in the hippocampus and amygdala in the model group was evident, whereas the expression of gamma-aminobutyric acid type A receptor subunit alpha1 and 5-hydroxytryptamine receptor 1A mRNA was significantly decreased in the hippocampus. CONCLUSIONS: These results indicated that FG7142 combined with restraint stress is sufficient to induce anxiety, and its mechanism is associated with downregulation of hippocampal gamma-aminobutyric acid type A receptor subunit alpha1 and 5-hydroxytryptamine 1A receptors.


Assuntos
Receptor 5-HT1A de Serotonina , Restrição Física , Animais , Ansiedade/etiologia , Regulação para Baixo , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptor 5-HT1A de Serotonina/metabolismo , Ácido gama-Aminobutírico/metabolismo
18.
Mol Pharmacol ; 101(5): 309-321, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35184045

RESUMO

Serotonin (5-HT) is a multifaceted neurotransmitter that has been described to play a role as a peripheral inflammatory mediator when released in ischemic or injured muscle. Dorsal root ganglia (DRG) neurons are key sensors of noxious stimuli that are released under inflammatory conditions or mechanical stress. Little information is available on the specific 5-HT receptor subtypes expressed in primary afferents that help regulate reflex pressor responses. In the present study, the whole-cell patch-clamp technique was employed to examine the modulation of voltage-gated calcium channel (CaV) 2.2 currents by 5-HT and to identify the 5-HT receptor subtype(s) mediating this response in acutely dissociated rat DRG neurons innervating triceps surae muscle. Our results indicate that exposure of 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI)-labeled DRG neurons to 5-HT can exert three modulatory effects on CaV currents: high inhibition, low inhibition, and enhancement. Both 5-HT-mediated inhibition responses were blocked after pretreatment with pertussis toxin (PTX), indicating that 5-HT receptors are coupled to CaV2.2 via Gα i/o protein subunits. Application of selective serotonin receptor type 1 (5-HT1) agonists revealed that modulation of CaV2.2 currents occurs primarily after 5-HT1A receptor subtype stimulation and minimally from 5-HT1D activation. Finally, the intrathecal administration of the selective 5-HT1A receptor agonist, 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), significantly (P < 0.05) decreased the pressor response induced by intra-arterial administration of lactic acid. This suggests that 5-HT1A receptors are expressed presynaptically on primary afferent neurons innervating triceps surae muscle. Our findings indicate that preferential stimulation of 5-HT1 receptors, expressed on thin fiber muscle afferents, serves to regulate the reflex pressor response to metabolic stimuli. SIGNIFICANCE STATEMENT: The monoamine serotonin (5-HT), released under ischemic conditions, can contribute to the development of inflammation that negatively affects the exercise pressor reflex. The 5-HT receptor subtype and signaling pathway that underlies calcium channel modulation in dorsal root ganglia afferents, innervating hindlimb muscles, are unknown. We show that 5-HT can either block (primarily via serotonin receptor type 1 (5-HT1)A subtypes) or enhance voltage-gated calcium channel (CaV2.2) currents. Our findings suggest 5-HT exhibits receptor subtype selectivity, providing a complexity of cellular responses.


Assuntos
Receptor 5-HT1A de Serotonina , Serotonina , Animais , Canais de Cálcio/metabolismo , Membro Posterior/metabolismo , Músculos/metabolismo , Ratos , Receptor 5-HT1A de Serotonina/metabolismo , Receptores de Serotonina/metabolismo , Células Receptoras Sensoriais/metabolismo , Serotonina/metabolismo , Serotonina/farmacologia
19.
Eur J Pharmacol ; 918: 174774, 2022 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-35077674

RESUMO

Deficits in the translation between egocentric-allocentric strategies may become another diagnostic mark for neurodegenerative disorders, especially Alzheimer's disease. Regarding the specific regional distribution of serotonin-1A receptor in brain areas mediating allocentric (externally-centered) spatial navigation to the escape location, here we studied the effects of median raphe nucleus serotonin-1A autoreceptors stimulation, [8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT); 4 µg/0.5 µl saline], of a selective cholinergic denervation by intracerebroventricular administration of the 192IgG saporin (1µl/each ventricle), on male Wistar rats search strategies in a Morris maze during acquisition, and before probe sessions. Despite some evidence of spatial hippocampal dependent knowledge to those PBS/Saline animals, their performance dropped to chance levels on probe trial. Therefore, we considered two probabilities and first analyzed the ability of the rats to make better use of one or more strategies. We showed statistically significant increases in the distances associated with egocentric (body-centered) non-spatial strategies, random searching in particular, in 192IgG/8OH rats, which led to their improved performance. Second, considering to what extent a shift in search strategy use improves performance indicated that 8-OH-DPAT alone did not affect learning since it appeared the related performance was impaired over days. However, the strategy choices made by 192IgG/8OH rats increased performance by more than 12% compared to 192IgG/Saline rats, an effect reversed with pre-treatment by serotonin-1A receptor antagonist, N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl) cyclohexane-carboxamide (WAY 100635). The results strongly suggest the potential role of serotonergic system, via the serotonin-1A receptors, in spatial navigation. We argue that the receptors are of interest as therapeutic targets that can be used against age-related cognitive decline.


Assuntos
8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Anticorpos Monoclonais/farmacologia , Encéfalo , Piperazinas/farmacologia , Piridinas/farmacologia , Receptor 5-HT1A de Serotonina/metabolismo , Saporinas/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Navegação Espacial , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Colinérgicos/farmacologia , Cognição/efeitos dos fármacos , Cognição/fisiologia , Infusões Intraventriculares , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Núcleos da Rafe/efeitos dos fármacos , Núcleos da Rafe/metabolismo , Ratos , Ratos Wistar , Antagonistas da Serotonina/farmacologia , Navegação Espacial/efeitos dos fármacos , Navegação Espacial/fisiologia
20.
Int J Neuropsychopharmacol ; 25(1): 36-45, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34555145

RESUMO

BACKGROUND: The serotonin 1A (5-HT1A) receptor has been implicated in depression and suicidal behavior. Lower resting cortisol levels are associated with higher 5-HT1A receptor binding, and both differentiate suicide attempters with depression. However, it is not clear whether 5-HT1A receptor binding and cortisol responses to stress are related to familial risk and resilience for suicidal behavior. METHODS: [11C]CUMI-101 positron emission tomography imaging to quantify regional brain 5-HT1A receptor binding was conducted in individuals considered to be at high risk for mood disorder or suicidal behavior on the basis of having a first- or second-degree relative(s) with an early onset mood disorder and history of suicidal behavior. These high-risk individuals were subdivided into the following groups: high risk resilient having no mood disorder or suicidal behavior (n = 29); high risk with mood disorder and no suicidal behavior history (n = 31); and high risk with mood disorder and suicidal behavior (n = 25). Groups were compared with healthy volunteers without a family history of mood disorder or suicidal behavior (n = 34). Participants underwent the Trier Social Stress Task (TSST). All participants were free from psychotropic medications at the time of the TSST and PET scanning. RESULTS: We observed no group differences in 5-HT1A receptor binding considering all regions simultaneously, nor did we observe heterogeneity of the effect of group across regions. These results were similar across outcome measures (BPND for all participants and BPp in a subset of the sample) and definitions of regions of interest (ROIs; standard or serotonin system-specific ROIs). We also found no group differences on TSST outcomes. Within the high risk with mood disorder and suicidal behavior group, lower BPp binding (ß = -0.084, SE = 0.038, P = .048) and higher cortisol reactivity to stress (ß = 9.25, 95% CI [3.27,15.23], P = .004) were associated with higher lethality attempts. There were no significant relationships between 5-HT1A binding and cortisol outcomes. CONCLUSIONS: 5-HT1A receptor binding in ROIs was not linked to familial risk or resilience protecting against suicidal behavior or mood disorder although it may be related to lethality of suicide attempt. Future studies are needed to better understand the biological mechanisms implicated in familial risk for suicidal behavior and how hypothalamic-pituitary-adrenal axis function influences such risk.


Assuntos
Hidrocortisona/metabolismo , Receptor 5-HT1A de Serotonina/metabolismo , Estresse Psicológico/metabolismo , Ideação Suicida , Tentativa de Suicídio , Adulto , Encéfalo/metabolismo , Transtorno Depressivo Maior/metabolismo , Feminino , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Piperazinas , Sistema Hipófise-Suprarrenal/metabolismo , Tomografia por Emissão de Pósitrons , Piridinas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...