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1.
Life Sci ; 259: 118271, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32798553

RESUMO

AIMS: Cannabidiolic acid (CBDA) is one of the most abundant phytocannabinoid acids in the Cannabis sativa plant. It has been shown that it is able to exert some therapeutic effects such as antiemetic, anti-inflammatory, anxiolytic or antidepressant, although some of them remain under debate. In the present study we aim to assess the potential behavioural effects of CBDA as well as its modulation of neuroinflammatory markers in the prefrontal cortex (PFC). MAIN METHODS: The effects of acute and repeated CBDA (0.001-1 mg/kg i.p.) treatments were evaluated on cognitive, emotional, motivational and nociceptive behaviours in male CD1 mice. For this, Y-maze and elevated plus maze paradigms, spontaneous locomotor activity, social interaction, hot-plate, formalin and tail suspension tests were used. We also studied the effects of CBDA on the rewarding responses of cocaine in the conditioned place preference (CPP) paradigm. Finally, PFC was dissected after acute and repeated CBDA treatments to evaluate inflammatory markers. KEY FINDINGS: Acute CBDA treatment induced antinociceptive responses in the hot-plate test. A 10-day CBDA treatment reduced despair-like behaviour in the tail suspension test. CBDA did not alter the results of the remaining behavioural tests assayed, including cocaine-induced reward in the CPP. Regarding the biochemical analysis, repeated CBDA treatment diminished the level of peroxisome proliferator-activated receptor gamma (PPAR-γ) and increased that of interleukin-6 (IL-6) protein in PFC. SIGNIFICANCE: These results show that CBDA has limited in vivo effects on the modulation of mice behaviour, supporting the current skepticism regarding its therapeutic potential.


Assuntos
Comportamento Animal/efeitos dos fármacos , Canabinoides/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Animais , Ansiolíticos/farmacologia , Antieméticos/farmacologia , Canabinoides/metabolismo , Cannabis/efeitos dos fármacos , Cognição/efeitos dos fármacos , Condicionamento Psicológico/efeitos dos fármacos , Dronabinol/farmacologia , Emoções/efeitos dos fármacos , Cloreto de Lítio/farmacologia , Masculino , Camundongos , Motivação/efeitos dos fármacos , Nociceptores/efeitos dos fármacos
2.
Nat Commun ; 11(1): 3996, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778725

RESUMO

Psychomotor stimulants increase dopamine levels in the striatum and promote locomotion; however, their effects on striatal pathway function in vivo remain unclear. One model that has been proposed to account for these motor effects suggests that stimulants drive hyperactivity via activation and inhibition of direct and indirect pathway striatal neurons, respectively. Although this hypothesis is consistent with the cellular actions of dopamine receptors and received support from optogenetic and chemogenetic studies, it has been rarely tested with in vivo recordings. Here, we test this model and observe that cocaine increases the activity of both pathways in the striatum of awake mice. These changes are linked to a dopamine-dependent cocaine-induced strengthening of upstream orbitofrontal cortex (OFC) inputs to the dorsomedial striatum (DMS) in vivo. Finally, depressing OFC-DMS pathway with a high frequency stimulation protocol in awake mice over-powers the cocaine-induced potentiation of OFC-DMS pathway and attenuates the expression of locomotor sensitization, directly linking OFC-DMS potentiation to cocaine-induced hyperactivity.


Assuntos
Estimulantes do Sistema Nervoso Central/farmacologia , Cocaína/farmacologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Hipercinese/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Animais , Comportamento Animal , Modelos Animais de Doenças , Dopamina , Feminino , Hipercinese/induzido quimicamente , Locomoção/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Optogenética
3.
PLoS One ; 15(8): e0237015, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760098

RESUMO

Graves' orbitopathy (GO) is characterised in early stages by orbital fibroblast inflammation, which can be aggravated by oxidative stress and often leads to fibrosis. Protein tyrosine protein 1B (PTP1B) is a regulator of inflammation and a therapeutic target in diabetes. We investigated the role of PTP1B in the GO mechanism using orbital fibroblasts from GO and healthy non-GO subjects. After 24 hours of transfection with PTPN1 siRNA, the fibroblasts were exposed to interleukin (IL)-1ß, cigarette smoke extract (CSE), H2O2, and transforming growth factor (TGF)-ß stimulations. Inflammatory cytokines and fibrosis-related proteins were analysed using western blotting and/or enzyme-linked immunosorbent assay (ELISA). Reactive oxygen species (ROS) release was detected using an oxidant-sensitive fluorescent probe. IL-1ß, tumor necrosis factor (TNF)-α, bovine thyroid stimulating hormone (bTSH), high-affinity human stimulatory monoclonal antibody of TSH receptor (M22), and insulin-like growth factor-1 (IGF-1) significantly increased PTP1B protein production in GO and non-GO fibroblasts. PTPN1 silencing significantly blocked IL-1ß-induced inflammatory cytokine production, CSE- and H2O2-induced ROS synthesis, and TGF-ß-induced expression of collagen Iα, α-smooth muscle actin (SMA), and fibronectin in GO fibroblasts. Silencing PTPN1 also decreased phosphorylation levels of Akt, p38, and c-Jun N-terminal kinase (JNK) and endoplasmic reticulum (ER)-stress response proteins in GO cells. PTP1B may be a potential therapeutic target of anti-inflammatory, anti-oxidant and anti-fibrotic treatment of GO.


Assuntos
Oftalmopatia de Graves/enzimologia , Oftalmopatia de Graves/terapia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Adulto , Animais , Apoptose , Bovinos , Sobrevivência Celular , Citocinas/biossíntese , Estresse do Retículo Endoplasmático , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Inativação Gênica , Oftalmopatia de Graves/patologia , Humanos , Técnicas In Vitro , Mediadores da Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/genética , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
4.
Br J Anaesth ; 125(4): 518-528, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32773216

RESUMO

BACKGROUND: Coherent alpha electroencephalogram (EEG) rhythms in the frontal cortex have been correlated with the hypnotic effects of propofol and dexmedetomidine, but less is known about frontal connectivity as a state-specific correlate of unresponsiveness as compared with long-range connectivity. We aimed to distinguish dose- and state-dependent effects of dexmedetomidine and propofol on EEG connectivity. METHODS: Forty-seven healthy males received either dexmedetomidine (n=23) or propofol (n=24) as target-controlled infusion with stepwise increments until loss of responsiveness (LOR). We attempted to arouse participants during constant dosing (return of responsiveness [ROR]), and the target concentration was then increased 50% to achieve presumed loss of consciousness. We collected 64-channel EEG data and prefrontal-frontal and anterior-posterior functional connectivity in the alpha band (8-14 Hz) was measured using coherence and weighted phase lag index (wPLI). Directed connectivity was measured with directed phase lag index (dPLI). RESULTS: Prefrontal-frontal EEG-based connectivity discriminated the states at the different drug concentrations. At ROR, prefrontal-frontal connectivity reversed to the level observed before LOR, indicating that connectivity changes were related to unresponsiveness rather than drug concentration. Unresponsiveness was associated with emergence of frontal-to-prefrontal dominance (dPLI: -0.13 to -0.40) in contrast to baseline (dPLI: 0.01-0.02). Coherence, wPLI, and dPLI had similar capability to discriminate the states that differed in terms of responsiveness and drug concentration. In contrast, anterior-posterior connectivity in the alpha band did not differentiate LOR and ROR. CONCLUSIONS: Local prefrontal-frontal EEG-based connectivity reflects unresponsiveness induced by propofol or dexmedetomidine, suggesting its utility in monitoring the anaesthetised state with these agents. CLINICAL TRIAL REGISTRATION: NCT01889004.


Assuntos
Dexmedetomidina/farmacologia , Eletroencefalografia/efeitos dos fármacos , Propofol/farmacologia , Adulto , Relação Dose-Resposta a Droga , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/fisiologia , Humanos , Masculino , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiologia
5.
Psychopharmacology (Berl) ; 237(8): 2435-2449, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32506234

RESUMO

RATIONALE: Νeurosteroids, like dehydroepiandrosterone (DHEA), play an important role in neurodegeneration and neural protection, but they are metabolized in androgens, estrogens, or other active metabolites. A newly developed synthetic DHEA analog, BNN27 ((20R)-3ß,21-dihydroxy-17R,20-epoxy-5-pregnene), exerts neurotrophic and neuroprotective actions without estrogenic or androgenic effects. OBJECTIVES: This study aimed to investigate potential anxiolytic or antidepressant properties of BNN27. METHODS: Male and female adult Wistar rats were treated with BNN27 (10, 30, or 90 mg/kg, i.p.) and subjected to behavioral tests measuring locomotion, exploration, and "depressive-like" behavior (open field, light/dark box, hole-board, and forced swim tests). The hippocampus and prefrontal cortex were collected for glutamate and GABA measurements, and trunk blood was collected for gonadal hormone analysis. RESULTS: Acute high-dose BNN27 reduced locomotion and exploratory behavior in both sexes. Intermediate acute doses (30 mg/kg) of BNN27 reduced exploration and testosterone levels only in males, and enhanced progesterone levels in both sexes. Notably, with the present design, BNN27 had neither anxiolytic nor antidepressant effects and did not affect estrogen levels. Interestingly, acute administration of a low BNN27 dose (10 mg/kg) increased glutamate turnover, GABA, and glutamine levels in the hippocampus. The same dose also enhanced glutamate levels in the prefrontal cortex of males only. Sex differences were apparent in the basal levels of behavioral, hormonal, and neurochemical parameters, as expected. CONCLUSIONS: BNN27 affects locomotion, progesterone, and testosterone levels, as well as the glutamatergic and GABAergic systems of the hippocampus and prefrontal cortex in a sex-dependent way.


Assuntos
Desidroepiandrosterona/farmacologia , Comportamento Exploratório/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Neuroesteroides/farmacologia , Caracteres Sexuais , Animais , Desidroepiandrosterona/química , Comportamento Exploratório/fisiologia , Feminino , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Locomoção/fisiologia , Masculino , Neuroesteroides/química , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Wistar
6.
PLoS One ; 15(6): e0235046, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579566

RESUMO

Post-ictal emergence of slow wave EEG (electroencephalogram) activity and burst-suppression has been associated with the therapeutic effects of the electroconvulsive therapy (ECT), indicating that mere "cerebral silence" may elicit antidepressant actions. Indeed, brief exposures to burst-suppressing anesthesia has been reported to elicit antidepressant effects in a subset of patients, and produce behavioral and molecular alterations, such as increased expression of brain-derived neurotrophic factor (BDNF), connected with antidepressant responses in rodents. Here, we have further tested the cerebral silence hypothesis by determining whether repeated exposures to isoflurane anesthesia reduce depressive-like symptoms or influence BDNF expression in male Wistar outbred rats (Crl:WI(Han)) subjected to chronic mild stress (CMS), a model which is responsive to repeated electroconvulsive shocks (ECS, a model of ECT). Stress-susceptible, stress-resilient, and unstressed rats were exposed to 5 doses of isoflurane over a 15-day time period, with administrations occurring every third day. Isoflurane dosing is known to reliably produce rapid EEG burst-suppression (4% induction, 2% maintenance; 15 min). Antidepressant and anxiolytic effects of isoflurane were assessed after the first, third, and fifth drug exposure by measuring sucrose consumption, as well as performance on the open field and the elevated plus maze tasks. Tissue samples from the medial prefrontal cortex and hippocampus were collected, and levels of BDNF (brain-derived neurotrophic factor) protein were assessed. We find that isoflurane anesthesia had no impact on the behavior of stress-resilient or anhedonic rats in selected tests; findings which were consistent-perhaps inherently related-with unchanged levels of BDNF.


Assuntos
Antidepressivos/farmacologia , Transtorno Depressivo/prevenção & controle , Isoflurano/farmacologia , Estresse Psicológico/prevenção & controle , Anestésicos Inalatórios , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Transtorno Depressivo/etiologia , Transtorno Depressivo/fisiopatologia , Modelos Animais de Doenças , Eletroconvulsoterapia/métodos , Eletroencefalografia , Eletrochoque/efeitos adversos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Humanos , Isoflurano/administração & dosagem , Masculino , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/fisiopatologia , Ratos Wistar , Estresse Psicológico/etiologia , Estresse Psicológico/fisiopatologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-32479008

RESUMO

Glutamatergic N-methyl-D-aspartate (NMDA) receptors have critical roles in several neurological and psychiatric diseases. Dizocilpine (MK-801) is a ligand at phencyclidine recognition sites that is associated with NMDA receptor-coupled cation channels, where it acts as a potent noncompetitive antagonist of central glutamate receptors. In this study, we investigate the effect of clozapine on MK-801-induced neurochemical and neurobehavioral alterations in the prefrontal cortex of mice. Acute administration of NMDA noncompetitive antagonist MK-801 impairs motor coordination, grip strength, and locomotor activity. Clozapine is the only medication that is indicated for treating refractory schizophrenia, due to its superior efficacy among all antipsychotic agents; however, its mechanism is not well understood. To understand its mechanism, we investigated the effects of clozapine on motor coordination, locomotor activity, and grip strength in mice against the NMDA receptor antagonist MK-801. MK-801 induced elevations in acetylcholinesterase (AChE) activity, monoamine oxidase (MAO) activity, and c-fos expression. The administration of clozapine inhibited the effects caused by MK-801 (0.2 mg/kg body weight). Motor coordination and grip strength paradigms that had been altered by MK-801 were restored by clozapine. Moreover, clozapine also ameliorated MK-801-induced elevation in AChE and MAO activity. Our immunostaining results demonstrated that clozapine treatment reduced overexpression of the neuronal activity marker c-fos in cortices of the brain. Results of the current study determine that clozapine ameliorated cognition in MK-801-treated mice via cholinergic and neural mechanisms. These findings show that clozapine possesses the potential to augment cognition in diseases such as schizophrenia.


Assuntos
Clozapina/farmacologia , Maleato de Dizocilpina/toxicidade , Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Esquizofrenia/tratamento farmacológico , Antagonistas da Serotonina/farmacologia , Animais , Antipsicóticos/farmacologia , Antagonistas de Aminoácidos Excitatórios/toxicidade , Masculino , Camundongos , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiopatologia , Esquizofrenia/induzido quimicamente
8.
Psychopharmacology (Berl) ; 237(8): 2345-2351, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32430517

RESUMO

BACKGROUND: Drug addiction is a chronically relapsing disorder in humans yet the underlying mechanism remained unclear. Recent studies suggested that histidine triad nucleotide binding protein1 (HINT1) may play significant roles in diverse neuropsychiatric diseases including drug addiction. METHODS: In the current study, we used different batches of mice to establish different stages of methamphetamine (METH)-induced behavioral sensitization (BS) to explore the dynamic changes throughout the process of addiction in different brain regions, including the prefrontal cortex (PFC), nucleus accumbens (NAc), caudate putamen (CPu), and hippocampus (Hip). In addition, we used HINT1 knockout (KO) mice to investigate the effect of HINT1 protein deletion on METH-induced BS. RESULTS: We found that in PFC of the METH group mice, the HINT1 expression level initially increased after development phase, and then dropped to the normal level during expression phase. However, there was no statistical difference in the HINT1 expression level in the other three encephalic regions (NAc, CPu, and Hip). The absence of HINT1 could promote METH-mediated addictive behavior to a certain extent, while the significant difference between genotypes only occurred in the development phase. CONCLUSIONS: Using the new technique, hip fractures were correctly predicted in 78% of cases compared with 36% when using the T-score. The accuracy of the prediction was not greatly reduced when using SSM and SAM (78% and 74% correct, respectively). Various geometric and BMD distribution traits were identified in the fractured and non-fractured groups.


Assuntos
Comportamento Aditivo/metabolismo , Estimulantes do Sistema Nervoso Central/efeitos adversos , Locomoção/efeitos dos fármacos , Metanfetamina/efeitos adversos , Proteínas do Tecido Nervoso/deficiência , Animais , Comportamento Aditivo/psicologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Locomoção/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo
9.
Psychopharmacology (Berl) ; 237(8): 2509-2516, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32468099

RESUMO

RATIONALE: Ventrolateral orbital cortex (VLO) has been found to play an important role in the regulation of neuropathic pain (NPP). As a traditional mood stabilizer, valproic acid (VPA) is currently employed in the treatment of NPP. However, whether VPA plays an analgesic role in VLO is still unknown. OBJECTIVES: To elucidate the underlying analgesic mechanism of microinjection of VPA into the VLO on spared nerve injury (SNI), an animal model of NPP. METHODS: We firstly examined the role of VPA by intraperitoneal and intral-VLO injection. Then, we accessed its role as a histone deacetylase inhibitor by intral-VLO microinjection of sodium butyrate. Finally, the GABAergic mechanism was measured through the intra-VLO microinjection of several agonists and antagonists of various GABAergic receptor subtypes. RESULTS: Both intraperitoneal and intral-VLO injection of VPA attenuated SNI-induced mechanical allodynia. Microinjection of sodium butyrate, one of the histone deacetylase inhibitors, into the VLO attenuated the mechanical allodynia. Besides, microinjection of valpromide, a derivative of VPA which is a GABAergic agonist, into the VLO also attenuated allodynia. Furthermore, microinjection of picrotoxin, a GABAA receptor antagonist, into the VLO attenuated mechanical allodynia; microinjection of picrotoxin before VPA into the VLO increased VPA-induced anti-allodynia. Besides, microinjection of CGP 35348, a GABAB receptor antagonist, into the VLO attenuated allodynia; microinjection of CGP 35348 before VPA into the VLO also increased VPA-induced anti-allodynia. What is more, microinjection of imidazole-4-acetic acid (I4AA), a GABAC receptor antagonist, into the VLO enhanced allodynia; microinjection of I4AA before VPA into the VLO decreased VPA-induced anti-allodynia. CONCLUSIONS: These results suggest that both the histone acetylation mechanism and GABAergic system are involved in mediating VLO-induced anti-hypersensitivity.


Assuntos
Analgésicos/administração & dosagem , Modelos Animais de Doenças , GABAérgicos/administração & dosagem , Neuralgia/tratamento farmacológico , Córtex Pré-Frontal/efeitos dos fármacos , Ácido Valproico/administração & dosagem , Animais , Relação Dose-Resposta a Droga , Masculino , Microinjeções/métodos , Neuralgia/metabolismo , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Sprague-Dawley
10.
Psychopharmacology (Berl) ; 237(7): 2161-2172, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32363439

RESUMO

The ability to discriminate between danger and safety is crucial for survival across species. Whereas danger signals predict the onset of a potentially threatening event, safety signals indicate the non-occurrence of an aversive event, thereby reducing fear and stress responses. While the neural basis of conditioned safety remains to be elucidated, fear extinction studies provide evidence that the infralimbic cortex (IL) modulates fear inhibition. In the current study, the IL was temporarily inactivated with local muscimol injections in male and female rats. The effect of IL inactivation on the acquisition and expression of conditioned safety was investigated utilizing the startle response. Temporary inactivation of the IL prior to conditioning did not affect the acquisition of conditioned safety, whereas IL inactivation during the expression test completely blocked the expression of conditioned safety in male and female rats. Inactivation of the neighboring prelimbic (PL) cortex during the expression test did not affect the expression of safety memory. Our findings suggest that the IL is a critical brain region for the expression of safety memory. Because patients suffering from anxiety disorders are often unable to make use of safety cues to inhibit fear, the present findings are of clinical relevance and could potentially contribute to therapy optimization of anxiety-related psychiatric disorders.


Assuntos
Condicionamento Clássico/fisiologia , Medo/fisiologia , Inibição Psicológica , Memória/fisiologia , Córtex Pré-Frontal/metabolismo , Reflexo de Sobressalto/fisiologia , Animais , Condicionamento Clássico/efeitos dos fármacos , Extinção Psicológica/efeitos dos fármacos , Extinção Psicológica/fisiologia , Medo/efeitos dos fármacos , Medo/psicologia , Feminino , Agonistas de Receptores de GABA-A/farmacologia , Masculino , Memória/efeitos dos fármacos , Muscimol/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Reflexo de Sobressalto/efeitos dos fármacos
11.
Psychopharmacology (Berl) ; 237(7): 1943-1957, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32399634

RESUMO

RATIONALE: The recreational use of naphyrone, a potent synthetic cathinone with a pyrovalerone structure, has raised questions about possible deleterious neurobehavioral consequences. OBJECTIVE: To investigate naphyrone-induced neurobehavioral effects and alterations in brain monoamines using two patterns of abuse, i.e., single and repeated (binge) use. METHODS: We studied naphyrone dose/induced locomotor activity relationship at 3, 10, 30, and 100 mg/kg in mice. We investigated the effects of single (30 mg/kg; acute injection) versus repeated (30 mg/kg ×3/day for 3 days; binge injection) intraperitoneal naphyrone administration on locomotor activity, anxiety-like behavior, spatial recognition memory, anhedonia, behavioral despair, and social interaction. We measured post-mortem prefrontal cortex levels of monoamines and modeled naphyrone pharmacokinetics and concentration/locomotor effect relationship. RESULTS: Both naphyrone administration patterns induced time-dependent increases in locomotor activity (p < 0.001 and p < 0.0001, respectively) and social interaction (p < 0.05 and p < 0.001, respectively) but did not alter spatial recognition memory or anhedonia. Acute naphyrone injection induced anxiety-like behavior (p < 0.01) and reduced resignation (p < 0.01) whereas binge administration induced non-anxiety-like behavior (p < 0.05) and did not alter behavioral despair. Both patterns increased the prefrontal cortex dopamine (p < 0.0001) and norepinephrine (p < 0.05 and p < 0.01, respectively) but not serotonin content. Naphyrone pharmacokinetics followed a two-compartment model with an overall elimination half-life of 0.3 h. The naphyrone concentration/locomotor effect relationship was described by an additive Emax model with an EC50 of 672 µg/L. CONCLUSIONS: Single naphyrone administration increases locomotor activity according to a direct concentration/effect relationship. The neurobehavioral effects after binge differs from those after single administration and are not explained by drug accumulation given the relatively fast elimination.


Assuntos
Drogas Desenhadas/farmacocinética , Drogas Ilícitas/farmacocinética , Locomoção/efeitos dos fármacos , Pentanonas/farmacocinética , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Pirrolidinas/farmacocinética , Animais , Relação Dose-Resposta a Droga , Locomoção/fisiologia , Masculino , Camundongos , Memória Espacial/efeitos dos fármacos , Memória Espacial/fisiologia
12.
Toxicon ; 183: 44-50, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32464148

RESUMO

3-nitropropionic acid (3-NP) is a mycotoxin widely used to produce a rat model of Huntington's disease. While there are numerous studies on the effect of this neurotoxin, still further investigation is required to understand the influence of this toxin on different regions of the brain. In the present study, there are two groups of rats of which one is treated with 3-NP. Behavioral, stereological and immunohistochemical analyses were conducted. The results show that locomotor activity is largely affected and anxiety is induced up to a certain level, but there is no gross manifestation of deficit in memory. Microscopic observations illustrate damages in the hippocampus and other parts of the brain. Astrogliosis and glial scars were another finding of this study. In conclusion, although 3-NP can be used as a model of Huntington's disease, it exerts a disseminated effect on different regions of the brain.


Assuntos
Micotoxinas/toxicidade , Nitrocompostos/toxicidade , Propionatos/toxicidade , Animais , Encéfalo , Cerebelo/efeitos dos fármacos , Gliose , Hipocampo/efeitos dos fármacos , Masculino , Córtex Pré-Frontal/efeitos dos fármacos , Ratos , Ratos Wistar
13.
J Neurosci ; 40(25): 4881-4887, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32430298

RESUMO

Understanding how disruption of prefrontal cortex (PFC) maturation during adolescence is crucial to reveal which neural processes could contribute to the onset of psychiatric disorders that display frontal cortical deficits. Of particular interest is the gain of GABAergic function in the PFC during adolescence and its susceptibility to the impact of transient blockade of NMDA receptor function. Here we assessed whether exposure to MK-801 during adolescence in male rats triggers a state of excitatory-inhibitory imbalance in the PFC that limits its functional capacity to regulate behavior in adulthood. Recordings from PFC brain slices revealed that MK-801 exposure during adolescence preferentially reduces the presynaptic functionality of GABAergic activity over that of excitatory synapses. As a result, an imbalance of excitatory-inhibitory synaptic activity emerges in the PFC that correlates linearly with the GABAergic deficit. Notably, the data also suggest that the diminished prefrontal GABAergic function could arise from a deficit in the recruitment of fast-spiking interneurons by excitatory inputs during adolescence. At the behavioral level, MK-801 exposure during adolescence did not disrupt the acquisition of trace fear conditioning, but markedly increased the level of freezing response during extinction testing. Infusion of the GABAA receptor-positive allosteric modulator Indiplon into the PFC before extinction testing reduced the level of freezing response in MK-801-treated rats to control levels. Collectively, the results indicate NMDA receptor signaling during adolescence enables the gain of prefrontal GABAergic function, which is required for maintaining proper excitatory-inhibitory balance in the PFC and its control of behavioral responses.SIGNIFICANCE STATEMENT A developmental disruption of prefrontal cortex maturation has been implicated in the pathophysiology of cognitive deficits in psychiatric disorders. Of particular interest is the susceptibility of the local GABAergic circuit to the impact of transient disruption of NMDA receptors. Here we found that NMDA receptor signaling is critical to enable the gain of prefrontal GABAergic transmission during adolescence for maintaining proper levels of excitatory-inhibitory balance in the PFC and its control of behavior.


Assuntos
Medo/fisiologia , Córtex Pré-Frontal/crescimento & desenvolvimento , Córtex Pré-Frontal/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Transmissão Sináptica/fisiologia , Animais , Maleato de Dizocilpina/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Extinção Psicológica/fisiologia , Medo/efeitos dos fármacos , Interneurônios/efeitos dos fármacos , Interneurônios/metabolismo , Masculino , Córtex Pré-Frontal/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Transmissão Sináptica/efeitos dos fármacos
14.
J Pharmacol Exp Ther ; 374(1): 126-133, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32358047

RESUMO

The novel small-molecule psychomotor stabilizer, IRL790, is currently in clinical trial for treatment of levodopa-induced dyskinesia and psychosis in patients with Parkinson disease. Here, we used naïve mice to investigate the effects of acute systemic administration of IRL790 on protein levels and phosphorylation states of proteins relevant for synaptic plasticity and transmission. IRL790 increased pro-brain-derived neurotrophic factor protein levels and phosphorylation at Ser1303 of the N-methyl-D-aspartate (NMDA) subtype 2B glutamate receptor (NR2B) in prefrontal cortex. IRL790 also increased the phosphorylation states at Ser19, Ser31, and Ser40, respectively, of tyrosine hydroxylase in striatum. IRL790 reduced protein levels of the NR2B receptor in striatum but not in prefrontal cortex. Taken together, we report that systemically administered IRL790 rapidly elicits changes in protein level and phosphorylation state of proteins associated with a beneficial effect on synaptic markers and neurotransmission. SIGNIFICANCE STATEMENT: The novel small-molecule psychomotor stabilizer, IRL790, is currently in clinical trial for treatment of levodopa-induced dyskinesia and psychosis in patients with Parkinson disease. In this study, we report that systemically administered IRL790 rapidly elicits changes in protein level and phosphorylation state of proteins associated with a beneficial effect on synaptic markers and neurotransmission.


Assuntos
Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Transmissão Sináptica/efeitos dos fármacos , Animais , Biomarcadores/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Dopamina/biossíntese , Relação Dose-Resposta a Droga , Ácido Glutâmico/metabolismo , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
15.
Proc Natl Acad Sci U S A ; 117(21): 11788-11798, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32393630

RESUMO

Down syndrome (DS) is the most common form of intellectual disability. The cognitive alterations in DS are thought to depend on brain regions critical for learning and memory such as the prefrontal cortex (PFC) and the hippocampus (HPC). Neuroimaging studies suggest that increased brain connectivity correlates with lower intelligence quotients (IQ) in individuals with DS; however, its contribution to cognitive impairment is unresolved. We recorded neural activity in the PFC and HPC of the trisomic Ts65Dn mouse model of DS during quiet wakefulness, natural sleep, and the performance of a memory test. During rest, trisomic mice showed increased theta oscillations and cross-frequency coupling in the PFC and HPC while prefrontal-hippocampal synchronization was strengthened, suggesting hypersynchronous local and cross-regional processing. During sleep, slow waves were reduced, and gamma oscillations amplified in Ts65Dn mice, likely reflecting prolonged light sleep. Moreover, hippocampal sharp-wave ripples were disrupted, which may have further contributed to deficient memory consolidation. Memory performance in euploid mice correlated strongly with functional connectivity measures that indicated a hippocampal control over memory acquisition and retrieval at theta and gamma frequencies, respectively. By contrast, trisomic mice exhibited poor memory abilities and disordered prefrontal-hippocampal functional connectivity. Memory performance and key neurophysiological alterations were rescued after 1 month of chronic administration of a green tea extract containing epigallocatequin-3-gallate (EGCG), which improves executive function in young adults with DS and Ts65Dn mice. Our findings suggest that abnormal prefrontal-hippocampal circuit dynamics are candidate neural mechanisms for memory impairment in DS.


Assuntos
Síndrome de Down/fisiopatologia , Hipocampo/fisiologia , Córtex Pré-Frontal/fisiologia , Reconhecimento Psicológico/fisiologia , Animais , Catequina/análogos & derivados , Catequina/farmacologia , Modelos Animais de Doenças , Função Executiva/efeitos dos fármacos , Feminino , Hipocampo/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Rede Nervosa/efeitos dos fármacos , Rede Nervosa/fisiologia , Fármacos Neuroprotetores/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Reconhecimento Psicológico/efeitos dos fármacos
16.
Toxicol Appl Pharmacol ; 395: 114980, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32234516

RESUMO

Toluene can be intentionally misused by adolescents to experience psychoactive effects. Toluene has a complex mechanism of action and broad behavioral effects, among which memory impairment is reported consistently. We have previously reported that repeated toluene inhalation (8000 ppm) increases layer 5 prelimbic pyramidal cells' excitability in the medial prefrontal cortex (mPFC) of adolescent rats. Toluene also produces reactive oxygen species (ROS), which activate glial cells. Here, we tested the hypothesis that the anti-inflammatory agent minocycline would decrease toluene's effects because it inhibits NF-κB (nuclear factor enhancer of the kappa light chains of activated B cells) and reduces pro-inflammatory cytokine and ROS production. Our results show that minocycline (50 mg/kg, ip, for 10 days) prevents the hyperexcitability of mPFC neurons observed after repeated 8000 ppm toluene exposure (30 min/day, 2×/day for 10 days). Minocycline prevents toluene-induced hyperexcitability by a mechanism that averts the loss of the slow calcium-dependent potassium current, and normalizes mPFC neurons' firing frequency. These effects are accompanied by significant decreased expression of astrocytes and activated microglia in the mPFC, reduced NLRP3 inflammasome activation and mRNA expression levels of the pro-inflammatory cytokine interleukin 1ß (IL-1ß), as well as increased mRNA expression of the anti-inflammatory cytokine transforming growth factor ß (TGF-ß). Minocycline also prevents toluene-induced memory impairment in adolescent rats in the passive avoidance task and the temporal order memory test in which the mPFC plays a central role. These results show that neuroinflammation produces several effects of repeated toluene administration at high concentrations, and minocycline can significantly prevent them.


Assuntos
Anti-Inflamatórios/administração & dosagem , Transtornos da Memória/prevenção & controle , Minociclina/administração & dosagem , Neurônios/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Tolueno/toxicidade , Administração por Inalação , Animais , Expressão Gênica/efeitos dos fármacos , Abuso de Inalantes , Interleucina-1beta/genética , Masculino , Transtornos da Memória/induzido quimicamente , Proteína 3 que Contém Domínio de Pirina da Família NLR/fisiologia , Neurônios/fisiologia , Córtex Pré-Frontal/patologia , Córtex Pré-Frontal/fisiopatologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/antagonistas & inibidores , Tolueno/administração & dosagem , Fator de Crescimento Transformador beta/genética
17.
Psychopharmacology (Berl) ; 237(6): 1873-1883, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32307560

RESUMO

BACKGROUND: The thalamus is a major target of dopaminergic projections and is densely connected with the prefrontal cortex. A better understanding of how dopamine changes thalamo-cortical communication may shed light on how dopamine supports cognitive function. Methylphenidate has been shown to facilitate cognitive processing and reduce connectivity between the thalamus and lateral prefrontal cortex. AIMS: The thalamus is a heterogeneous structure, and the present study sought to clarify how the intrinsic connections of thalamic sub-regions are differentially impacted by acute dopamine transporter blockade. METHODS: Sixty healthy volunteers were orally administered either 20 mg of methylphenidate (N = 29) or placebo (N = 31) in a double-blind, randomized, between-subject design. Multi-echo fMRI was used to assess intrinsic functional connectivity of sub-regions of the thalamus during a resting state scan. An N-back working-memory paradigm provided a measure of cognitive performance. RESULTS: Acute methylphenidate significantly reduced connectivity of the lateral prefrontal cortex with the motor and somatosensory sub-regions of the thalamus and reduced connectivity with the parietal and visual sub-regions at a trend level. Connectivity with the premotor, prefrontal, and temporal sub-regions was not impacted. The intrinsic connectivity between the thalamus and the lateral prefrontal cortex was not associated with working-memory performance. CONCLUSIONS: Methylphenidate decreases functional connections between the lateral prefrontal cortex and thalamus broadly, while sparing intrinsic connectivity with thalamic sub-regions involved with working-memory and language related processes. Collectively, our results suggest that the dopamine transporter regulates functional connections between the prefrontal cortex and non-cognitive areas of the thalamus.


Assuntos
Imagem por Ressonância Magnética/métodos , Memória de Curto Prazo/efeitos dos fármacos , Metilfenidato/administração & dosagem , Rede Nervosa/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Tálamo/efeitos dos fármacos , Adulto , Inibidores da Captação de Dopamina/administração & dosagem , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Tálamo/diagnóstico por imagem , Tálamo/fisiologia , Adulto Jovem
18.
Chem Biol Interact ; 323: 109076, 2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-32240654

RESUMO

A growing body of evidence indicates that exposure to nonylphenol (NP), a typical persistent organic pollutant (POP), in early life results in the impairment of the central nervous system (CNS), but the underlying mechanism still remains to be elucidated. High levels of pro-inflammatory cytokines in the brain have been implicated in the CNS damages. The animal model of exposure to NP in early life was established by maternal gavage during the pregnancy and lactation in the present study. We found that exposure to NP in early life increased the levels of pro-inflammatory cytokines in the rat prefrontal cortex. Interestingly, the levels of pro-inflammatory cytokines in the intestine as well as in the serum were also increased by NP exposure. Furthermore, the increased permeability of intestinal barrier and blood-brain barrier (BBB), two critical barriers in the gut to brain communication, was observed in the rats exposed to NP in early lives. The decreased expression of zonula occludens-1 (ZO-1) and claudin-1 (CLDN-1), tight junction proteins (TJs) that responsible for maintaining the permeability of intestinal barrier and BBB, was found, which may underlie these increases in permeability. Taken together, these results suggested that the disturbed gut-brain communication may contribute to the increased levels of pro-inflammatory cytokines in the prefrontal cortex caused by NP exposure in early life.


Assuntos
Citocinas/metabolismo , Trato Gastrointestinal/patologia , Mediadores da Inflamação/metabolismo , Fenóis/toxicidade , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/patologia , Animais , Animais Recém-Nascidos , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Líquido Cefalorraquidiano/metabolismo , Claudina-1/metabolismo , Citocinas/sangue , Feminino , Trato Gastrointestinal/efeitos dos fármacos , Mediadores da Inflamação/sangue , Intestinos/efeitos dos fármacos , Intestinos/patologia , Exposição Materna , Permeabilidade , Córtex Pré-Frontal/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Ratos Sprague-Dawley , Proteína da Zônula de Oclusão-1/metabolismo
19.
Proc Natl Acad Sci U S A ; 117(18): 9991-10002, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32312805

RESUMO

The initial response to an addictive substance can facilitate repeated use: That is, individuals experiencing more positive effects are more likely to use that drug again. Increasing evidence suggests that psychoactive cannabinoid use in adolescence enhances the behavioral effects of cocaine. However, despite the behavioral data, there is no neurobiological evidence demonstrating that cannabinoids can also alter the brain's initial molecular and epigenetic response to cocaine. Here, we utilized a multiomics approach (epigenomics, transcriptomics, proteomics, and phosphoproteomics) to characterize how the rat brain responds to its first encounter with cocaine, with or without preexposure to the synthetic cannabinoid WIN 55,212-2 (WIN). We find that in adolescent (but not in adult) rats, preexposure to WIN results in cross-sensitization to cocaine, which correlates with histone hyperacetylation and decreased levels of HDAC6 in the prefrontal cortex (PFC). In the PFC, we also find that WIN preexposure blunts the typical mRNA response to cocaine and instead results in alternative splicing and chromatin accessibility events, involving genes such as Npas2 Moreover, preexposure to WIN enhances the effects of cocaine on protein phosphorylation, including ERK/MAPK-targets like gephyrin, and modulates the synaptic AMPAR/GluR composition both in the PFC and the nucleus accumbens (NAcc). PFC-NAcc gene network topological analyses, following cocaine exposure, reveal distinct top nodes in the WIN preexposed group, which include PACAP/ADCYAP1. These preclinical data demonstrate that adolescent cannabinoid exposure reprograms the initial behavioral, molecular, and epigenetic response to cocaine.


Assuntos
Comportamento Aditivo/genética , Comportamento Animal/efeitos dos fármacos , Canabinoides/efeitos adversos , Cocaína/efeitos adversos , Adolescente , Animais , Comportamento Aditivo/induzido quimicamente , Comportamento Aditivo/patologia , Benzoxazinas/efeitos adversos , Benzoxazinas/farmacologia , Canabinoides/farmacologia , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/genética , Cocaína/farmacologia , Epigênese Genética/efeitos dos fármacos , Epigênese Genética/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Desacetilase 6 de Histona/genética , Humanos , Proteínas de Membrana/farmacologia , Morfolinas/efeitos adversos , Morfolinas/farmacologia , Naftalenos/efeitos adversos , Naftalenos/farmacologia , Fosfoproteínas/efeitos dos fármacos , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , Córtex Pré-Frontal/efeitos dos fármacos , Proteoma/efeitos dos fármacos , Ratos , Transcriptoma/efeitos dos fármacos
20.
Nat Commun ; 11(1): 1635, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32242018

RESUMO

It remains unclear why many patients with depression do not respond to antidepressant treatment. In three cohorts of individuals with depression and treated with serotonin-norepinephrine reuptake inhibitor (N = 424) we show that responders, but not non-responders, display an increase of GPR56 mRNA in the blood. In a small group of subjects we also show that GPR56 is downregulated in the PFC of individuals with depression that died by suicide. In mice, we show that chronic stress-induced Gpr56 downregulation in the blood and prefrontal cortex (PFC), which is accompanied by depression-like behavior, and can be reversed by antidepressant treatment. Gpr56 knockdown in mouse PFC is associated with depressive-like behaviors, executive dysfunction and poor response to antidepressant treatment. GPR56 peptide agonists have antidepressant-like effects and upregulated AKT/GSK3/EIF4 pathways. Our findings uncover a potential role of GPR56 in antidepressant response.


Assuntos
Antidepressivos/administração & dosagem , Transtorno Depressivo Maior/tratamento farmacológico , Receptores Acoplados a Proteínas-G/metabolismo , Adulto , Animais , Estudos de Coortes , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/metabolismo , Feminino , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Receptores Acoplados a Proteínas-G/genética , Inibidores de Captação de Serotonina/administração & dosagem , Resultado do Tratamento
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