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1.
Eval Health Prof ; : 1632787241259186, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38843535

RESUMO

Surveys of health professionals typically have low response rates, which have decreased in recent years. We report on the methods used, participation rates, and study time for 11 national questionnaire studies of dentists conducted from 2014-2022. Participation rates decreased (87%-25%). Concurrent with this decrease was a decrease in the intensity with which the practitioners were recruited. Participation rates were higher when postal mail invitation and paper options were used (84% vs. 58%, p < .001). Completion rates were nearly twice as high in studies that recruited in waves than those that did not (61% vs. 35%, p = .003). Study time varied from 2.6 to 28.4 weeks. Study time was longest when postal mail and completion on paper were used (26.0 vs. 11.3 weeks, p = .01). Among studies using only online methods, study time was longer when invitations were staggered than when all invitations went out in one bolus (means 12.0 and 5.2, p = .04). Study time was positively correlated with participation rates (Spearman r = .80, p = .005). General dentists participated at an average of 12% higher rates than specialists. Recruitment methodology, such as recruiting in waves or stages, should be considered when designing surveys.

2.
Neurosci Biobehav Rev ; 162: 105715, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38734195

RESUMO

Obsessive-compulsive disorder (OCD) is a chronic and debilitating illness that has been considered a polygenic and multifactorial disorder, challenging effective therapeutic interventions. Although invaluable advances have been obtained from human and rodent studies, several molecular and mechanistic aspects of OCD etiology are still obscure. Thus, the use of non-traditional animal models may foster innovative approaches in this field, aiming to elucidate the underlying mechanisms of disease from an evolutionary perspective. The zebrafish (Danio rerio) has been increasingly considered a powerful organism in translational neuroscience research, especially due to the intrinsic features of the species. Here, we outline target mechanisms of OCD for translational research, and discuss how zebrafish-based models can contribute to explore neurobehavioral aspects resembling those found in OCD. We also identify possible advantages and limitations of potential zebrafish-based models, as well as highlight future directions in both etiological and therapeutic research. Lastly, we reinforce the use of zebrafish as a promising tool to unravel the biological basis of OCD, as well as novel pharmacological therapies in the field.


Assuntos
Modelos Animais de Doenças , Transtorno Obsessivo-Compulsivo , Pesquisa Translacional Biomédica , Peixe-Zebra , Animais , Transtorno Obsessivo-Compulsivo/fisiopatologia , Transtorno Obsessivo-Compulsivo/genética , Humanos , Comportamento Animal/fisiologia
3.
Adv Neurotoxicol ; 11: 177-208, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38741945

RESUMO

The gut microbes perform several beneficial functions which impact the periphery and central nervous systems of the host. Gut microbiota dysbiosis is acknowledged as a major contributor to the development of several neuropsychiatric and neurological disorders including bipolar disorder, depression, anxiety, Parkinson's disease, Alzheimer's disease, attention deficit hyperactivity disorder, and autism spectrum disorder. Thus, elucidation of how the gut microbiota-brain axis plays a role in health and disease conditions is a potential novel approach to prevent and treat brain disorders. The zebrafish (Danio rerio) is an invaluable vertebrate model that possesses conserved brain and intestinal features with those of humans, thus making zebrafish a valued model to investigate the interplay between the gut microbiota and host health. This chapter describes current findings on the utility of zebrafish in understanding molecular mechanisms of neurotoxicity mediated via the gut microbiota-brain axis. Specifically, it highlights the utility of zebrafish as a model organism for understanding how anthropogenic chemicals, pharmaceuticals and bacteria exposure affect animals and human health via the gut-brain axis.

4.
ACS Appl Mater Interfaces ; 16(11): 13597-13610, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38453642

RESUMO

Atmospheric pressure coaxial gaseous discharge tubes (DTs) with helium have demonstrated potential for in vitro inactivation or sensitization of glioblastoma cancer cells. Here, we study the effect of two configurations of the DT electrode system on its electromagnetic emissivity as well as other physical factors (heating and UV emission) that form in the vicinity of this device. We demonstrate that the configuration of the DT electrodes that concentrates the discharge streamers near the top of the device has a distant (cm scale) deactivation effect on U87-MG glioblastoma cancer cells when irradiated, without measurable UV components in the DT optical emission spectra. This effect persists even through different barriers such as glass, plastic, or quartz Petri dishes but is eliminated when glass or plastic dishes are filled with water. These findings demonstrate the potential for development of noninvasive, physical-based treatment methods of deep-tissue tumors.


Assuntos
Glioblastoma , Gases em Plasma , Humanos , Gases em Plasma/farmacologia , Hélio , Glioblastoma/terapia , Fenômenos Eletromagnéticos , Pressão Atmosférica
5.
Artigo em Inglês | MEDLINE | ID: mdl-38325745

RESUMO

Functional changes in dopamine transporter (DAT) are related to various psychiatric conditions, including bipolar disorder (BD) symptoms. In experimental research, the inhibition of DAT induces behavioral alterations that recapitulate symptoms found in BD patients, including mania and depressive mood. Thus, developing novel animal models that mimic BD-related conditions by pharmacologically modulating the dopaminergic signaling is relevant. The zebrafish (Danio rerio) has been considered a suitable vertebrate system for modeling BD-like responses, due to the well-characterized behavioral responses and evolutionarily conservation of the dopaminergic system of this species. Here, we investigate whether GBR 12909, a selective inhibitor of DAT, causes neurobehavioral alterations in zebrafish similar to those observed in BD patients. Behaviors were recorded after a single intraperitoneal (i.p.) administration of GBR 12909 at different doses (3.75, 7.5, 15 and 30 mg/kg). To observe temporal effects on behavior, swim path parameters were measured immediately after the administration period during 30 min. Locomotion, anxiety-like behavior, social preference, aggression, despair-like behavior, and oxidative stress-related biomarkers in the brain were measured 30 min post administration. GBR 12909 induced prominent effects on locomotor activity and vertical exploration during the 30-min period. Hyperactivity was observed in GBR 30 group after 25 min, while all doses markedly reduced vertical drifts. GBR 12909 elicited hyperlocomotion, anxiety-like behavior, decreased social preference, aggression, and induced depressive-like behavior in a behavioral despair task. Depending on the dose, GBR 12909 also decreased SOD activity and TBARS levels, as well as increased GR activity and NPSH content. Collectively, our novel findings show that a single GBR 12909 administration evokes neurobehavioral changes that recapitulate manic- and depressive-like states observed in rodents, fostering the use of zebrafish models to explore BD-like responses in translational neuroscience research.


Assuntos
Mania , Peixe-Zebra , Animais , Humanos , Comportamento Animal , Encéfalo , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Estresse Oxidativo , Fenótipo
6.
Cancer Epidemiol Biomarkers Prev ; 33(4): 525-533, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38319289

RESUMO

BACKGROUND: Mailed fecal immunochemical test (FIT) outreach can improve colorectal cancer screening participation. We assessed the reach and effectiveness of adding notifications to mailed FIT programs. METHODS: We conducted secondary analyses of a stepped-wedge evaluation of an enhanced mailed FIT program (n = 15 clinics). Patients were stratified by prior FIT completion. Those with prior FIT were sent a text message (Group 1); those without were randomized 1:1 to receive a text message (Group 2) or live phone call (Group 3). All groups were sent automated phone call reminders. In stratified analysis, we measured reach and effectiveness (FIT completion within 6 months) and assessed patient-level associations using generalized estimating equations. RESULTS: Patients (n = 16,934; 83% Latino; 72% completed prior FIT) were reached most often by text messages (78%), followed by live phone calls (71%), then automated phone calls (56%). FIT completion was higher in patients with prior FIT completion versus without [44% (Group 1) vs. 19% (Group 2 + Group 3); P < 0.01]. For patients without prior FIT, effectiveness was higher in those allocated to a live phone call [20% (Group 3) vs. 18% (Group 2) for text message; P = 0.04] and in those who personally answered the live call (28% vs. 9% no call completed; P < 0.01). CONCLUSIONS: Text messages reached the most patients, yet effectiveness was highest in those who personally answered the live phone call. IMPACT: Despite the broad reach and low cost of text messages, personalized approaches may more successfully boost FIT completion.


Assuntos
Neoplasias Colorretais , Envio de Mensagens de Texto , Humanos , Detecção Precoce de Câncer , Sistemas de Alerta , Programas de Rastreamento , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Sangue Oculto
7.
Biomolecules ; 13(11)2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-38002313

RESUMO

The action of tetraalkylammonium ions, from tetrametylammonium (TMA) to tetrapentylammonium (TPtA), on the recombinant and native acid-sensing ion channels (ASICs) was studied using the patch-clamp approach. The responses of ASIC1a, ASIC2a, and native heteromeric ASICs were inhibited by TPtA. The peak currents through ASIC3 were unaffected, whereas the steady-state currents were significantly potentiated. This effect was characterized by an EC50 value of 1.22 ± 0.12 mM and a maximal effect of 3.2 ± 0.5. The effects of TPtA were voltage-independent but significantly decreased under conditions of strong acidification, which caused saturation of ASIC responses. Molecular modeling predicted TPtA binding in the acidic pocket of closed ASICs. Bound TPtA can prevent acidic pocket collapse through a process involving ASIC activation and desensitization. Tetraethylammonium (TEA) inhibited ASIC1a and native ASICs. The effect was independent of the activating pH but decreased with depolarization, suggesting a pore-blocking mechanism.


Assuntos
Canais Iônicos Sensíveis a Ácido , Prótons , Canais Iônicos Sensíveis a Ácido/metabolismo , Concentração de Íons de Hidrogênio
8.
J Gen Physiol ; 155(11)2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37728574

RESUMO

Opposite effects of 1,4-dihydropyridine (DHP) agonists and antagonists on the L-type calcium channels are a challenging problem. Cryo-EM structures visualized DHPs between the pore-lining helices S6III and S6IV in agreement with published mutational data. However, the channel conformations in the presence of DHP agonists and antagonists are virtually the same, and the mechanisms of the ligands' action remain unclear. We docked the DHP agonist S-Bay k 8644 and antagonist R-Bay k 8644 in Cav1.1 channel models with or without π-bulges in helices S6III and S6IV. Cryo-EM structures of the DHP-bound Cav1.1 channel show a π-bulge in helix S6III but not in S6IV. The antagonist's hydrophobic group fits into the hydrophobic pocket formed by residues in S6IV. The agonists' polar NO2 group is too small to fill up the pocket. A water molecule could sterically fit into the void space, but its contacts with isoleucine in helix S6IV (motif INLF) would be unfavorable. In a model with π-bulged S6IV, this isoleucine turns away from the DHP molecule and its position is occupied by the asparagine from the same motif INLF. The asparagine provides favorable contacts for the water molecule at the agonist's NO2 group but unfavorable contacts for the antagonist's methoxy group. In our models, the DHP antagonist stabilizes entirely α-helical S6IV. In contrast, the DHP agonist stabilizes π-bulged helix S6IV whose C-terminal part turned and rearranged the activation-gate region. This would stabilize the open channel. Thus, agonists, but not antagonists, would promote channel opening by stabilizing π-bulged helix S6IV.


Assuntos
Cálcio , Di-Hidropiridinas , Éster Metílico do Ácido 3-Piridinacarboxílico, 1,4-Di-Hidro-2,6-Dimetil-5-Nitro-4-(2-(Trifluormetil)fenil) , Asparagina , Microscopia Crioeletrônica , Isoleucina , Dióxido de Nitrogênio , Di-Hidropiridinas/farmacologia , Canais de Sódio
9.
Int J Mol Sci ; 24(16)2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37629153

RESUMO

Proton-gated channels of the ASIC family are widely distributed in central neurons, suggesting their role in common neurophysiological functions. They are involved in glutamatergic neurotransmission and synaptic plasticity; however, the exact function of these channels remains unclear. One problem is that acidification of the synaptic cleft due to the acidic content of synaptic vesicles has opposite effects on ionotropic glutamate receptors and ASICs. Thus, the pH values required to activate ASICs strongly inhibit AMPA receptors and almost completely inhibit NMDA receptors. This, in turn, suggests that ASICs can provide compensation for post-synaptic responses in the case of significant acidifications. We tested this hypothesis by patch-clamp recordings of rat brain neuron responses to acidifications and glutamate receptor agonists at different pH values. Hippocampal pyramidal neurons have much lower ASICs than glutamate receptor responses, whereas striatal interneurons show the opposite ratio. Cortical pyramidal neurons and hippocampal interneurons show similar amplitudes in their responses to acidification and glutamate. Consequently, the total response to glutamate agonists at different pH levels remains rather stable up to pH 6.2. Besides these pH effects, the relationship between the responses mediated by glutamate receptors and ASICs depends on the presence of Mg2+ and the membrane voltage. Together, these factors create a complex picture that provides a framework for understanding the role of ASICs in synaptic transmission and synaptic plasticity.


Assuntos
Sinapses , Vesículas Sinápticas , Animais , Ratos , Transmissão Sináptica , Corpo Estriado , Agonistas de Aminoácidos Excitatórios , Ácido Glutâmico
10.
Environ Res ; 237(Pt 1): 116869, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37567382

RESUMO

Aflatoxin B1 (AFB1), a dietary toxin from the mold Aspergillus species, is well acknowledged to elicit extra-hepatic toxicity in both animals and humans. The neurotoxicity of AFB1 has become a global public health concern. Contemporary research on how AFB1 enters the brain to elicit neuronal dysregulation leading to noxious neurological outcomes has increased greatly in recent years. The current review discusses several neurotoxic outcomes and susceptible targets of AFB1 toxicity at cellular, molecular and genetic levels. Specifically, neurotoxicity studies involving the use of brain homogenates, neuroblastoma cell line IMR-32, human brain microvascular endothelial cells, microglial cells, and astrocytes, as well as mammalian and non-mammalian models to unravel the mechanisms associated with AFB1 exposure are highlighted. Further, some naturally occurring bioactive compounds with compelling therapeutic effects on AFB1-induced neurotoxicity are reviewed. In conclusion, available data from literature highlight AFB1 as a neurotoxin and its possible pathological contribution to neurological disorders. Further mechanistic studies aimed at discovering and developing effective therapeutics for AFB1 neurotoxicity is warranted.

11.
Cancer Epidemiol Biomarkers Prev ; 32(11): 1608-1616, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37566431

RESUMO

BACKGROUND: Mailed fecal immunochemical test (FIT) outreach can improve colorectal cancer screening rates, yet little is known about how to optimize these programs for effectiveness and cost. METHODS: PROMPT was a pragmatic, stepped-wedge, cluster-randomized effectiveness trial of mailed FIT outreach. Participants in the standard condition were mailed a FIT and received live telephone reminders to return it. Participants in the enhanced condition also received a tailored advance notification (text message or live phone call) and two automated phone call reminders. The primary outcome was 6-month FIT completion; secondary outcomes were any colorectal cancer screening completion at 6 months, implementation, and program costs. RESULTS: The study included 27,585 participants (80% ages 50-64, 82% Hispanic/Latino; 68% preferred Spanish). A higher proportion of enhanced participants completed FIT at 6 months than standard participants, both in intention-to-treat [+2.8%, 95% confidence interval (CI; 0.4-5.2)] and per-protocol [limited to individuals who were reached; +16.9%, 95% CI (12.3-20.3)] analyses. Text messages and automated calls were successfully delivered to 91% to 100% of participants. The per-patient cost for standard mailed FIT was $10.84. The enhanced program's text message plus automated call reminder cost an additional $0.66; live phone calls plus an automated call reminder cost an additional $10.82 per patient. CONCLUSIONS: Adding advance notifications and automated calls to a standard mailed FIT program boosted 6-month FIT completion rates at a small additional per-patient cost. IMPACT: Enhancements to mailed FIT outreach can improve colorectal cancer screening participation. Future research might test the addition of educational video messaging for screening-naïve adults.


Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Humanos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Detecção Precoce de Câncer/métodos , Programas de Rastreamento/métodos , Sangue Oculto , Sistemas de Alerta , Telefone , Pessoa de Meia-Idade
12.
Behav Processes ; 210: 104912, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37406867

RESUMO

Anxiety is a protective behavior when animals face aversive conditions. The open field test (OFT) is used to assess the spatio-temporal dynamics of exploration, in which both homebase formation and recognition of environmental cues may reflect habituation to unfamiliar conditions. Because emotional- and affective-like states influence exploration patterns and mnemonic aspects, we aimed to verify whether the exploratory behaviors of two zebrafish populations showing distinct baselines of anxiety differ in two OFT sessions. Firstly, we assessed the baseline anxiety-like responses of short fin (SF) and leopard (LEO) populations using the novel tank test (NTT) and light-dark test (LDT) in 6-min trials. Fish were later tested in two consecutive days in the OFT, where the spatial occupancy and exploratory profile were analyzed for 30 min. In general, LEO showed pronounced diving behavior and scototaxis in the NTT and LDT, respectively, in which an "anxiety index" corroborated their exacerbated anxiety-like behavior. In the OFT, the SF population spent less time to establish the homebase in the 1st trial, while only LEO showed a markedly reduction in the latency to homebase formation in the 2nd trial. Both locomotion and homebase-related activities were decreased in the 2nd trial, in which animals also revealed increased occupancy in the center area of the apparatus. Moreover, we verified a significant percentage of homebase conservation for both populations, while only SF showed reduced the number of trips and increased the average length of trips. Principal component analyses revealed that distinct factors accounted for total variances between trials for each population tested. While homebase exploration was reduced in the 2nd trial for SF, an increased occupancy in the center area and hypolocomotion were the main factors that contribute to the effects observed in LEO during re-exposure to the OFT. In conclusion, our novel data support the homebase conservation in zebrafish subjected to independent OFT sessions, as well as corroborate a population-dependent effect on specific behavioral parameters related to exploration.


Assuntos
Comportamento Animal , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Comportamento Animal/fisiologia , Ansiedade , Locomoção , Comportamento Exploratório/fisiologia , Fenótipo
14.
J Med Chem ; 66(15): 10354-10363, 2023 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-37489955

RESUMO

Human proliferating cell nuclear antigen (PCNA) is a critical mediator of DNA replication and repair, acting as a docking platform for replication proteins. Disrupting these interactions with a peptidomimetic agent presents as a promising avenue to limit proliferation of cancerous cells. Here, a p21-derived peptide was employed as a starting scaffold to design a modular peptidomimetic that interacts with PCNA and is cellular and nuclear permeable. Ultimately, a peptidomimetic was produced which met these criteria, consisting of a fluorescein tag and SV40 nuclear localization signal conjugated to the N-terminus of a p21 macrocycle derivative. Attachment of the fluorescein tag was found to directly affect cellular uptake of the peptidomimetic, with fluorescein being requisite for nuclear permeability. This work provides an important step forward in the development of PCNA targeting peptidomimetics for use as anti-cancer agents or as cancer diagnostics.


Assuntos
Peptidomiméticos , Humanos , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Peptidomiméticos/farmacologia , Replicação do DNA , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Fluoresceínas
16.
Artigo em Inglês | MEDLINE | ID: mdl-37127059

RESUMO

While pain results from the activation of nociceptors following noxious stimuli, mounting evidence links pain- and stress-related responses in mammals. In zebrafish, the activation of hypothalamic-pituitary-interrenal (HPI) axis may also regulate body pigmentation (the camouflage response). Here, we aimed to investigate a putative relationship between pain-, stress-, and camouflage-related parameters in adult zebrafish. To answer this question, we assessed whether intraperitoneal acetic acid injection can activate the HPI axis, measuring whole-body cortisol and the camouflage response as physiological endpoints in the presence or absence of morphine or naloxone, an opioid antagonist. Acetic acid induced a stereotypic circling behavior in the top of the tank, accompanied by abdominal writhing-like response, a specific phenotype that reflects local nociceptive effect. Both whole-body cortisol levels and camouflage response increased in the acetic acid group, while morphine prevented these responses, and naloxone antagonized morphine-induced effects. Moreover, we observed positive correlations between representative behavioral, physiological and skin coloration endpoints, and a "pain index" was proposed to summarize phenotypic profile of zebrafish under different pharmacological manipulations. Collectively, these findings suggest a coordinated activation of pain, camouflage- and stress-related pathways following acetic acid injection in zebrafish. Our data also support that camouflage response represents a novel and relevant biomarker for future probing pain and stress neurobiology, with a robust sensitivity to opioidergic drugs.


Assuntos
Ácido Acético , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Ácido Acético/toxicidade , Ácido Acético/metabolismo , Hidrocortisona/metabolismo , Naloxona/farmacologia , Naloxona/metabolismo , Morfina/toxicidade , Morfina/metabolismo , Dor , Fenótipo , Mamíferos/metabolismo
17.
Clin Microbiol Infect ; 29(8): 1015-1023, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37086781

RESUMO

BACKGROUND: Pneumocystis jirovecii pneumonia (PCP) incidence is increasing in patients without HIV infection. In contrast to PCP in patients infected with HIV, diagnosis is often delayed and illness is associated with increased mortality. OBJECTIVES: To provide a comprehensive review of clinical presentation, risk factors, diagnostic strategies, and treatment options for PCP in patients without HIV infection. SOURCES: Web-based literature review on PCP for trials, meta-analyses, and systematic reviews using PubMed. The restriction to the English language was applied. CONTENT: Common underlying conditions in patients without HIV infection having PCP are haematological malignancies, autoimmune and inflammatory diseases, solid organ or haematopoietic stem cell transplant, and previous corticosteroid exposure. New risk groups include patients receiving monoclonal antibodies and immunomodulating therapies. Patients without HIV infection who have PCP present with rapid onset and progression of pneumonia, increased duration of hospitalization and a significantly higher mortality rate than patients infected with HIV. PCP is diagnosed by a combination of clinical symptoms and radiological as well as mycological features. Results of immunofluorescence microscopy from bronchoalveolar lavage, PCR testing, and computed tomography imaging as well as the evaluation of clinical presentation are required. The established treatment regime consists of trimethoprim and sulfamethoxazole. IMPLICATIONS: Although the number of patients with immunosuppression due to causes different from HIV is increasing, a simultaneous rise in PCP incidence is observed. In the group of patients without HIV infection, rapid onset of symptoms, a more complex course, and a high mortality rate are recorded. Therefore, the time to diagnosis must be as short as possible to initiate effective therapy promptly. This review aims to raise awareness of PCP in an increasingly affected at-risk group and provides clinicians with a practical guide for efficient diagnosis and targeted therapy. Furthermore, it intends to display current inadequacies in research on the topic of PCP.


Assuntos
Infecções por HIV , Pneumocystis carinii , Pneumonia por Pneumocystis , Humanos , Infecções por HIV/tratamento farmacológico , Pneumonia por Pneumocystis/diagnóstico , Pneumonia por Pneumocystis/tratamento farmacológico , Fatores de Risco , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Lavagem Broncoalveolar
18.
Artigo em Inglês | MEDLINE | ID: mdl-36921663

RESUMO

Stress is a physiological reaction that allows the organisms to cope with challenging situations daily. Thus, elucidating the behavioral outcomes following different stressors is of great importance in translational research. Here, we aimed to characterize the main factors which explain similarities and differences of two stress protocols on zebrafish exploratory activity. To answer this point, we performed behavioral analyses aiming to simplify the data structure associated with homebase-related measurements in an integrated manner. Adult zebrafish were exposed to conspecific alarm substance for 5 min (acute stress protocol - AS) or submitted to 7 days of unpredictable chronic stress (UCS). Immediately after AS or in the subsequent day following UCS (8th day), fish were individually tested in the open field and the behaviors were recorded for 30 min to posterior identification of homebase locations. For both protocols, behavioral clustering revealed two major clusters, grouping homebase- and locomotor-related parameters, respectively. While AS increased both positive and negative correlations between exploratory and locomotor endpoints, a significant increase in negative correlations was found in UCS-challenged fish. Comparison of the principal component analyses data set revealed a reduced exploratory activity using the homebase in AS group, while decreased locomotion in the periphery and anxiety-like behaviors were evidenced in UCS fish. In conclusion, our findings revealed a different structure of behavior in zebrafish following AS and UCS protocols, supporting the existence of distinct behavioral strategies to cope with acute and chronic stress. Furthermore, we expand the use of homebase-related measurements as a valuable tool to investigate complex behavioral modulations in future translational neuropsychiatry research.


Assuntos
Ansiedade , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Comportamento Animal/fisiologia , Atividade Motora/fisiologia , Comportamento Exploratório/fisiologia
19.
Front Physiol ; 14: 1018551, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36711018

RESUMO

The pharmacology of acid-sensitive ion channels (ASICs) is diverse, but potent and selective modulators, for instance for ASIC2a, are still lacking. In the present work we studied the effect of five 2-aminobenzimidazole derivatives on native ASICs in rat brain neurons and recombinant receptors expressed in CHO cells using the whole-cell patch clamp method. 2-aminobenzimidazole selectively potentiated ASIC3. Compound Ru-1355 strongly enhanced responses of ASIC2a and caused moderate potentiation of native ASICs and heteromeric ASIC1a/ASIC2a. The most active compound, Ru-1199, caused the strongest potentiation of ASIC2a, but also potentiated native ASICs, ASIC1a and ASIC3. The potentiating effects depended on the pH and was most pronounced with intermediate acidifications. In the presence of high concentrations of Ru-1355 and Ru-1199, the ASIC2a responses were biphasic, the initial transient currents were followed by slow component. These slow additional currents were weakly sensitive to the acid-sensitive ion channels pore blocker diminazene. We also found that sustained currents mediated by ASIC2a and ASIC3 are less sensitive to diminazene than the peak currents. Different sensitivities of peak and sustained components to the pore-blocking drug suggest that they are mediated by different open states. We propose that the main mechanism of action of 2-aminobenzimidazole derivatives is potentiation of the open state with slow kinetics of activation and desensitization.

20.
Eur Biophys J ; 52(1-2): 111-119, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36690863

RESUMO

The gating mechanism of acid-sensitive ion channels (ASICs) remains unclear, despite the availability of atomic-scale structures in various functional states. The collapse of the acidic pocket and structural changes in the low-palm region are assumed to trigger activation. For the acidic pocket, protonation of some residues can minimize repulsion in the collapsed conformation. The relationship between low-palm rearrangements and gating is unknown. In this work, we performed a Monte Carlo energy optimization of known ASIC1a structures and determined the residue-residue interactions in different functional states. For rearrangements in the acidic pocket, our results are consistent with previously proposed mechanisms, although significant complexity was revealed for the residue-residue interactions. The data support the proposal of a gating mechanism in the low-palm region, in which residues E80 and E417 share a proton to activate the channel.


Assuntos
Canais Iônicos Sensíveis a Ácido , Prótons , Concentração de Íons de Hidrogênio , Canais Iônicos Sensíveis a Ácido/química , Canais Iônicos Sensíveis a Ácido/metabolismo , Conformação Molecular
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