RESUMO
Na+/K+-ATPase (NKA) plays an important role in the central nervous system. However, little is known about its function in the microglia. Here, we found that NKAα1 forms a complex with the purinergic P2X7 receptor (P2X7R), an adenosine 5'-triphosphate (ATP)-gated ion channel, under physiological conditions. Chronic stress or treatment with lipopolysaccharide plus ATP decreased the membrane expression of NKAα1 in microglia, facilitated P2X7R function, and promoted microglia inflammatory activation via activation of the NLRP3 inflammasome. Accordingly, global deletion or conditional deletion of NKAα1 in microglia under chronic stress-induced aggravated anxiety-like behavior and neuronal hyperexcitability. DR5-12D, a monoclonal antibody that stabilizes membrane NKAα1, improved stress-induced anxiety-like behavior and ameliorated neuronal hyperexcitability and neurogenesis deficits in the ventral hippocampus of mice. Our results reveal that NKAα1 limits microglia inflammation and may provide a target for the treatment of stress-related neuroinflammation and diseases.
Assuntos
Microglia , Receptores Purinérgicos P2X7 , Animais , Camundongos , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Ansiedade , Microglia/metabolismo , Receptores Purinérgicos P2X7/genética , Receptores Purinérgicos P2X7/metabolismoRESUMO
Pain is a complex phenomenon that involves sensory, emotional, and cognitive components. The posterior insula cortex (pIC) has been shown to integrate multisensory experience with emotional and cognitive states. However, the involvement of the pIC in the regulation of affective behavior in pain remains unclear. Here, we investigate the role of pain-related pIC neurons in the regulation of anxiety-like behavior during acute pain. We combined a chemogenetic approach with targeted recombination in active populations (TRAP) in mice. Global chemogenetic inhibition of pIC neurons attenuates chemically-induced mechanical hypersensitivity without affecting pain-related anxiety-like behavior. In contrast, inhibition of pain-related pIC neurons reduces both mechanical hypersensitivity and pain-related anxiety-like behavior. The present study provides important insights into the role of pIC neurons in the regulation of sensory and affective pain-related behavior.
Assuntos
Dor Aguda , Ansiedade , Hiperalgesia , Córtex Insular , Neurônios , Animais , Ansiedade/fisiopatologia , Hiperalgesia/fisiopatologia , Neurônios/metabolismo , Camundongos , Dor Aguda/fisiopatologia , Dor Aguda/psicologia , Masculino , Comportamento Animal , Camundongos Endogâmicos C57BLRESUMO
Pregnancy is associated with neural and behavioral plasticity, systemic inflammation, and oxidative stress, yet the impact of inflammation and oxidative stress on maternal neural and behavioral plasticity during pregnancy is unclear. We hypothesized that healthy pregnancy transiently reduces learning and memory and these deficits are associated with pregnancy-induced elevations in inflammation and oxidative stress. Cognitive performance was tested with novel object recognition (recollective memory), Morris water maze (spatial memory), and open field (anxiety-like) behavior tasks in female Sprague-Dawley rats of varying reproductive states [nonpregnant (nulliparous), pregnant (near term), and 1-2 mo after pregnancy (primiparous); n = 7 or 8/group]. Plasma and CA1 proinflammatory cytokines were measured with a MILLIPLEX magnetic bead assay. Plasma oxidative stress was measured via advanced oxidation protein products (AOPP) assay. CA1 markers of oxidative stress, neuronal activity, and apoptosis were quantified via Western blot analysis. Our results demonstrate that CA1 oxidative stress-associated markers were elevated in pregnant compared with nulliparous rats (P ≤ 0.017) but there were equivalent levels in pregnant and primiparous rats. In contrast, reproductive state did not impact CA1 inflammatory cytokines, neuronal activity, or apoptosis. Likewise, there was no effect of reproductive state on recollective or spatial memory. Even so, spatial learning was impaired (P ≤ 0.007) whereas anxiety-like behavior (P ≤ 0.034) was reduced in primiparous rats. Overall, our data suggest that maternal hippocampal CA1 is protected from systemic inflammation but vulnerable to peripartum oxidative stress. Peripartum oxidative stress elevations, such as in pregnancy complications, may contribute to peripartum neural and behavioral plasticity.NEW & NOTEWORTHY Healthy pregnancy is associated with elevated maternal systemic and brain oxidative stress. During postpregnancy, brain oxidative stress remains elevated whereas systemic oxidative stress is resolved. This sustained maternal brain oxidative stress is associated with learning impairments and decreased anxiety-like behavior during the postpregnancy period.
Assuntos
Estresse Oxidativo , Ratos Sprague-Dawley , Animais , Feminino , Gravidez , Ratos , Inflamação/metabolismo , Inflamação/fisiopatologia , Memória , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/fisiopatologia , Memória Espacial , Citocinas/metabolismo , Citocinas/sangue , Ansiedade/metabolismo , Neurônios/metabolismo , Aprendizagem em Labirinto , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/sangueRESUMO
Nectin-like family members (Necls) are involved in synaptic organization. In contrast to that of Necl-2/CADM1/SynCAM1, which is critical in synaptic events, investigation of Necl-4/CADM4/SynCAM4 in synapses has largely lagged behind given the particularity of homophilic self-interactions compared to interactions with other Necls. We sought to further understand the role of Necl-4 in synapses and found that knockout of Necl-4 led to aberrant expression levels of proteins mediating synaptic function in cortex homogenates and augmented accumulation of ionotropic glutamate receptor in postsynaptic density fractions, although a compensatory effect of Necl-1 on the expression levels existed. Concurrently, we also found increased synaptic clefts in the cortex and simplified dendritic morphology of primary cultured cortical neurons. Experiments on individual behaviors suggested that compared to their wild-type littermates, Necl-4-KO mice exhibited impaired acquisition of spatial memory and working memory and enhanced behavioral despair and anxiety-like behavior. These findings suggest that Necl-4 mediates synaptic function and related behaviors through an indispensable role and offer a new perspective about collaboration and specialization among Necls.
Assuntos
Moléculas de Adesão Celular , Neurônios , Camundongos , Animais , Nectinas/genética , Moléculas de Adesão Celular/metabolismo , Neurônios/metabolismo , Sinapses/metabolismoRESUMO
Recent research highlights the pivotal role of the maternal gut microbiome during pregnancy in shaping offspring neurodevelopment. In this study, we investigated the impact of maternal intake of a multispecies probiotic formulation during a critical prenatal window (from gestational day 6 until birth) on neurodevelopmental trajectories in mice. Our findings demonstrate significant and persistent benefits in emotional behavior, gut microbiota composition, and expression of tight junction-related genes, particularly in male offspring, who exhibited heightened sensitivity to the probiotic intervention compared to females. Additionally, we observed elevated gene expression levels of the anti-inflammatory cytokine IL-10 and the oxytocin receptor (Oxtr) in the prefrontal cortex (PFC) of exposed juvenile offspring; however, these changes persisted only in the adult male offspring. Furthermore, the sustained increase in the expression of the proton-coupled oligopeptide transporter 1 (PepT1), which is involved in the transport of bacterial peptidoglycan motifs, in the PFC of exposed male offspring suggests a potential mechanistic pathway underlying the observed sex-dependent effects on behavior and gene expression. These results underscore the potential of prenatal multispecies probiotic interventions to promote long-term neurodevelopmental outcomes, with implications for precision microbial reconstitution aimed at promoting healthy neurodevelopment and behavior.
Assuntos
Microbioma Gastrointestinal , Probióticos , Receptores de Ocitocina , Animais , Feminino , Probióticos/administração & dosagem , Gravidez , Microbioma Gastrointestinal/fisiologia , Masculino , Camundongos , Receptores de Ocitocina/metabolismo , Receptores de Ocitocina/genética , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Córtex Pré-Frontal/metabolismo , Camundongos Endogâmicos C57BL , Interleucina-10/metabolismoRESUMO
The vagus nerve, a pivotal link within the gut-brain axis, plays a critical role in maintaining homeostasis and mediating communication between the gastrointestinal tract and the brain. It has been reported that gastrointestinal infection by Salmonella typhimurium (S. typhimurium) triggers gut inflammation and manifests as anxiety-like behaviors, yet the mechanistic involvement of the vagus nerve remains to be elucidated. In this study, we demonstrated that unilateral cervical vagotomy markedly attenuated anxiety-like behaviors induced by S. typhimurium SL1344 infection in C57BL/6 mice, as evidenced by the open field test and marble burying experiment. Furthermore, vagotomy significantly diminished neuronal activation within the nucleus of the solitary tract and amygdala, alongside mitigating aberrant glial cell activation in the hippocampus and amygdala. Additionally, vagotomy notably decreases serum endotoxin levels, counters the increase in splenic Salmonella concentration, and modulates the expression of inflammatory cytokines-including IL-6, IL-1ß, and TNF-α-in both the gastrointestinal tract and brain, with a concurrent reduction in IL-22 and CXCL1 expression. This intervention also fostered the enrichment of beneficial gut microbiota, including Alistipes and Lactobacillus species, and augmented the production of gamma-aminobutyric acid (GABA) in the gut. Administration of GABA replicated the vagotomy's beneficial effects on reducing gut inflammation and anxiety-like behavior in infected mice. However, blockade of GABA receptors with picrotoxin abrogated the vagotomy's protective effects against gut inflammation, without influencing its impact on anxiety-like behaviors. Collectively, these findings suggest that vagotomy exerts a protective effect against infection by promoting GABA synthesis in the colon and alleviating anxiety-like behavior. This study underscores the critical role of the vagus nerve in relaying signals of gut infection to the brain and posits that targeting the gut-brain axis may offer a novel and efficacious approach to preventing gastrointestinal infections and associated behavioral abnormalities.
Assuntos
Ansiedade , Microbioma Gastrointestinal , Camundongos Endogâmicos C57BL , Vagotomia , Nervo Vago , Ácido gama-Aminobutírico , Animais , Ansiedade/metabolismo , Camundongos , Nervo Vago/metabolismo , Masculino , Ácido gama-Aminobutírico/metabolismo , Salmonella typhimurium , Citocinas/metabolismo , Eixo Encéfalo-Intestino , Encéfalo/metabolismo , Infecções por Salmonella/metabolismo , Comportamento Animal , Hipocampo/metabolismo , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Inflamação/metabolismo , Tonsila do Cerebelo/metabolismoRESUMO
Maternal obesity during perinatal period increases the risk of metabolic and behavioral deleterious outcomes in the offspring, since it is critical for brain development, maturation, and reorganization. These processes are highly modulated by the endocannabinoid system (ECS), which comprises the main lipid ligands anandamide and 2-arachidonoylglycerol, cannabinoid receptors 1 and 2 (CB1R and CB2R), and several metabolizing enzymes. The ECS is overactivated in obesity and it contributes to the physiological activity of the hypothalamus-pituitary-adrenal (HPA) axis, promoting stress relief. We have previously demonstrated that maternal high-fat diet during gestation and lactation programmed the food preference for fat in adolescent male offspring and adult male and female offspring. In the present study, we hypothesized that maternal diet-induced obesity would induce sex-specific changes of the ECS in the hypothalamus and dorsal hippocampus of rat offspring associated with dysregulation of the HPA axis and stress-related behavior in adolescence. Rat dams were fed a control (C) or an obesogenic high-fat high-sugar diet (OD) for nine weeks prior to mating and throughout gestation and lactation. Maternal obesity differentially altered the CB1R in the hypothalamus of neonate offspring, with significant increase in male but not in female pups, associated with decreased CB2R prior to obesity development. In adolescence, maternal obesity induced anxiety-like behavior only in adolescent females which was associated with increased content of CB1R in the dorsal hippocampus. Our findings suggest that the early origins of anxiety disorders induced by maternal exposome is associated with dysregulation of the brain ECS, with females being more susceptible.
RESUMO
Deficiencies in maternal nutrition have long-term consequences affecting brain development of the progeny and its behavior. In the present work, female mice were exposed to a normal-protein or a low-protein diet during gestation and lactation. We analyzed behavioral and molecular consequences of malnutrition in dams and how it affects female offspring at weaning. We have observed that a low-protein diet during pregnancy and lactation leads to anxiety-like behavior and anhedonia in dams. Protein malnutrition during the perinatal period delays physical and neurological development of female pups. Glucocorticoid levels increased in the plasma of malnourished female offspring but not in dams when compared to the control group. Interestingly, the expression of glucocorticoid receptor (GR) was reduced in hippocampus and amygdala on both malnourished dams and female pups. In addition, malnourished pups exhibited a significant increase in the expression of Dnmt3b, Gadd45b, and Fkbp5 and a reduction in Bdnf VI variant mRNA in hippocampus. In contrast, a reduction on Dnmt3b has been observed on the amygdala of weaned mice. No changes have been observed on global methylation levels (5-methylcytosine) in hippocampal genomic DNA neither in dams nor female offspring. In conclusion, deregulated behaviors observed in malnourished dams might be mediated by a low expression of GR in brain regions associated with emotive behaviors. Additionally, low-protein diet differentially deregulates the expression of genes involved in DNA methylation/demethylation machinery in female offspring but not in dams, providing an insight into regional- and age-specific mechanisms due to protein malnutrition.
Assuntos
Fator Neurotrófico Derivado do Encéfalo , Metilação de DNA , Hipocampo , Comportamento Materno , Efeitos Tardios da Exposição Pré-Natal , Receptores de Glucocorticoides , Proteínas de Ligação a Tacrolimo , Animais , Feminino , Gravidez , Camundongos , Receptores de Glucocorticoides/metabolismo , Receptores de Glucocorticoides/genética , Proteínas de Ligação a Tacrolimo/genética , Proteínas de Ligação a Tacrolimo/metabolismo , Comportamento Materno/fisiologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Hipocampo/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Estresse Psicológico/metabolismo , Tonsila do Cerebelo/metabolismo , Dieta com Restrição de Proteínas , DNA Metiltransferase 3B , Deficiência de Proteína/metabolismo , Deficiência de Proteína/complicações , Ansiedade/etiologia , Glucocorticoides/metabolismo , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Transtornos do Neurodesenvolvimento/etiologia , Transtornos do Neurodesenvolvimento/metabolismo , Transtornos do Neurodesenvolvimento/genética , Animais Recém-Nascidos , Proteínas GADD45 , Antígenos de DiferenciaçãoRESUMO
Ventral adult hippocampal neurogenesis may be a key factor in determining individual levels of vulnerability to stress and related psychiatric disorders. However, the underlying mechanism remains unclear. Here, we show that the expression of Tau and Tau isoforms is markedly increased in the ventral dentate gyrus (vDG) after social defeat stress in young adult mice. Furthermore, glycogen synthase kinase-3ß and calcium/calmodulin-dependent protein kinase II-α activity and calcium/calmodulin-dependent protein kinase II-ß upregulation substantially promote Tau phosphorylation, which disrupts the dendritic structural plasticity of granule cells in the vDG of the hippocampus, and this action is necessary and sufficient for the stress response. In addition, Tau substantially inhibits the proliferation of newborn neurons in the vDG by regulating the PI3K-AKT signaling pathway in a mouse model of social defeat stress. Taken together, our findings reveal a novel mechanism by which Tau exacerbates stress responses and anxiety-related behavior by inhibiting the proliferation and maturation of hippocampal vDG neurons, providing a potential molecular target for the treatment of anxiety-like behavior induced by stress.
Assuntos
Cálcio , Giro Denteado , Camundongos , Animais , Giro Denteado/metabolismo , Cálcio/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Hipocampo/fisiologia , Ansiedade , Neurogênese/fisiologia , Proteínas tau/metabolismoRESUMO
Objectives: Maternal physical activity may impact behavioral and electrophysiological aspects of brain function, with short- and long-term effects on pre- and postnatal neurodevelopment of the offspring. This study evaluated in the rat the effects of maternal voluntary physical activity (MVPA) on food intake and weight gain in the dams, as well as anxiety-like behavior, short-term memory and the brain excitability-related phenomenon known as cortical spreading depression (CSD) on the mother-pup dyad.Methods: Female Wistar rats (n=33) were individually housed in cages containing a running wheel for a 30-days adaptation period before mating. Rats were classified as inactive (I); active (A) or very active (VA) according to the distance spontaneously travelled daily. During gestation, the dams continued to have access to the running wheel. Mothers and their respective pups (1 pup per mother) were evaluated in the open field test (OFT), object recognition test (ORT), elevated plus maze test (EPMT) and the CSD propagation features.Results: MVPA was directly associated with increased food intake and weight gain during gestation, and maternal anxiolytic-like behavioral responses in the OFT. Pups from VA mothers showed a high discrimination index for shape recognition memory (ORT) and decreased propagation velocities of CSD, when compared with the inactive group.Discussion: The data suggest that MVPA during the gestational period induces neuroplasticity and may modulate the brain functions in the mother-infant dyad in the rat.
Assuntos
Condicionamento Físico Animal , Humanos , Ratos , Animais , Feminino , Ratos Wistar , Condicionamento Físico Animal/fisiologia , Encéfalo , Ingestão de Alimentos , Aumento de PesoRESUMO
Past studies in animal models have extensively investigated the impact of early life experiences on behavioral development, yet relatively few have specifically examined the implications of peripubertal experiences on the evolution of competitive behavior across distinct stages of adulthood. In the current research, we probed potential differences in competitive behavior during emerging adulthood (3 months old) and middle adulthood (12 months old) in 81 Sprague-Dawley male rats exposed to three different peripubertal (postnatal Days 37-60) environments: an enriched environment (EE), a chronic unpredictable mild stress (CUMS) condition, and a control condition. Anxiety-like behavior served as a positive control in our study. Results revealed significant variations in competitive behavior among the groups during emerging adulthood. The EE group displayed the least anxiety and outperformed their peers in food-reward-oriented competition, whereas the CUMS group excelled in status-driven, agonistic competition. However, these behavioral differentiations gradually attenuated by middle adulthood, at which point the control group began to show an advantage. Our findings suggest that although peripubertal experiences significantly shape competitive behavior in the emerging adulthood stage, this effect diminishes over time and is nearly non-detectable during mid-adulthood, underscoring the fluidity of behavioral development and demonstrating that the effects of peripubertal experiences can be modulated by subsequent life experiences.
Assuntos
Comportamento Animal , Comportamento Competitivo , Ratos Sprague-Dawley , Estresse Psicológico , Animais , Masculino , Ratos , Comportamento Competitivo/fisiologia , Comportamento Animal/fisiologia , Estresse Psicológico/fisiopatologia , Ansiedade/fisiopatologia , Meio Ambiente , Fatores EtáriosRESUMO
A widely applied pesticide of azoxystrobin, is increasingly detected in the water environment. Concern has been raised against its potential detriment to aquatic ecosystems. It has been shown that exposure to azoxystrobin interfere with the locomotor behavior of zebrafish larvae. This study aims to investigate whether exposure to environmental levels of azoxystrobin (2 µg/L, 20 µg/L, and 200 µg/L) changes the behavior of male adult zebrafish. Herein, we evaluated behavioral response (locomotor, anxiety-like, and exploratory behaviors), histopathology, biochemical indicators, and gene expression in male adult zebrafish upon azoxystrobin exposure. The study showed that exposure to azoxystrobin for 42 days remarkably increased the locomotor ability of male zebrafish, resulted in anxiety-like behavior, and inhibited exploratory behavior. After treatment with 200 µg/L azoxystrobin, vasodilatation, and congestion were observed in male zebrafish brains. Exposure to 200 µg/L azoxystrobin notably elevated ROS level, MDA concentration, CAT activity, and AChE activity, while inhibiting SOD activity, GPx activity, ACh concentration, and DA concentration in male zebrafish brains. Moreover, the expression levels of genes related to the antioxidant, cholinergic, and dopaminergic systems were significantly changed. This suggests that azoxystrobin may interfere with the homeostasis of neurotransmitters by causing oxidative stress in male zebrafish brains, thus affecting the behavioral response of male zebrafish.
Assuntos
Pirimidinas , Estrobilurinas , Poluentes Químicos da Água , Peixe-Zebra , Animais , Masculino , Peixe-Zebra/metabolismo , Ecossistema , Estresse Oxidativo , Colinérgicos/metabolismo , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismoRESUMO
Accumulating evidence suggests an involvement of sphingolipids, vital components of cell membranes and regulators of cellular processes, in the pathophysiology of both Parkinson's disease and major depressive disorder, indicating a potential common pathway in these neuropsychiatric conditions. Based on this interaction of sphingolipids and synuclein proteins, we explored the gene expression patterns of α-, ß-, and γ-synuclein in a knockout mouse model deficient for acid sphingomyelinase (ASM), an enzyme catalyzing the hydrolysis of sphingomyelin to ceramide, and studied associations with behavioral parameters. Normalized Snca, Sncb, and Sncg gene expression was determined by quantitative PCR in twelve brain regions of sex-mixed homozygous (ASM-/-, n = 7) and heterozygous (ASM+/-, n = 7) ASM-deficient mice, along with wild-type controls (ASM+/+, n = 5). The expression of all three synuclein genes was brain region-specific but independent of ASM genotype, with ß-synuclein showing overall higher levels and the least variation. Moreover, we discovered correlations of gene expression levels between brain regions and depression- and anxiety-like behavior and locomotor activity, such as a positive association between Snca mRNA levels and locomotion. Our results suggest that the analysis of synuclein genes could be valuable in identifying biomarkers and comprehending the common pathological mechanisms underlying various neuropsychiatric disorders.
Assuntos
Ansiedade , Encéfalo , Depressão , Modelos Animais de Doenças , Locomoção , Camundongos Knockout , Esfingomielina Fosfodiesterase , Animais , Esfingomielina Fosfodiesterase/genética , Esfingomielina Fosfodiesterase/metabolismo , Camundongos , Encéfalo/metabolismo , Depressão/genética , Depressão/metabolismo , Ansiedade/genética , Ansiedade/metabolismo , Locomoção/genética , Masculino , Sinucleínas/metabolismo , Sinucleínas/genética , Comportamento Animal , Feminino , Genótipo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Camundongos Endogâmicos C57BLRESUMO
Alzheimer's disease (AD) is one of the largest health crises in the world. There are limited pharmaceutical interventions to treat AD, however, and most of the treatment options are not for cure or prevention, but rather to slow down the progression of the disease. The aim of this study was to examine the effect of tactile stimulation (TS) on AD-like symptoms and pathology in APPNL-G-F/NL-G-F mice, a mouse model of AD. The results show that TS reduces the AD-like symptoms on tests of cognition, motor, and anxiety-like behaviors and these improvements in behavior are associated with reduced AD pathology in APP mice. Thus, TS appears to be a promising noninvasive strategy for slowing the onset of dementia in aging animals.
Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Camundongos , Animais , Doença de Alzheimer/terapia , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides , Disfunção Cognitiva/patologia , Camundongos Transgênicos , Cognição , Ansiedade/terapia , Modelos Animais de Doenças , Precursor de Proteína beta-AmiloideRESUMO
The ventral pallidum (VP) is involved in the regulation of a variety of behaviors such as motor, reward, and behavioral motivation, and the ability to perform these functions properly is dependent on a high degree of wakefulness. It is unknown whether VP CaMKIIa-expression (VPCaMKIIa) neurons also have a role in sleep-wake regulation and related neuronal circuit mechanisms. In the present experiment, we first used in vivo fiber photometry to find the population activity of VPCaMKIIa neurons which increased during the transitions from non-rapid-eye movement (NREM) sleep to wakefulness and NREM sleep to rapid-eye-movement (REM) sleep, with decreased during the transitions from wakefulness to NREM sleep. Then chemogenetic activation of VPCaMKIIa neurons induced an increase in wakefulness that lasted for 2 h. Mice that were exposed to short-term optogenetic stimulation woke up quickly from stable NREM sleep, and long-term optogenetic stimulation maintained wakefulness. In addition, optogenetic activation of the axons of VPCaMKIIa neurons in the lateral habenula (LHb) also facilitated the initiation and maintenance of wakefulness and mediated anxiety-like behavior. Finally, the method of chemogenetic inhibition was employed to suppress VPCaMKIIa neurons, and yet, inhibition of VPCaMKIIa neuronal activity did not result in an increase in NREM sleep and a decrease in wakefulness. Overall, our data illustrate that the activation of VPCaMKIIa neurons is of great importance for promoting wakefulness.
Assuntos
Prosencéfalo Basal , Vigília , Camundongos , Animais , Vigília/fisiologia , Neurônios/fisiologia , Sono/fisiologia , Sono REMRESUMO
Insomnia and anxiety are two common and closely related clinical problems that pose a threat to individuals' physical and mental well-being. There is a possibility that some nuclei and neural circuits in the brain are shared by both insomnia and anxiety. In the present study, using a combination of chemogenetics, optogenetics, polysomnographic recordings and the classic tests of anxiety-like behaviors, we verified that the calmodulin-dependent protein kinase II alpha (CaMKIIa) neurons of the ventromedial hypothalamus (VMH) are involved in the regulation of both wakefulness and anxiety. Chemogenetic manipulation of the VMH CaMKIIa neurons elicited an apparent increase in wakefulness during activation, whereas inhibition decreased wakefulness mildly. It substantiated that the VMH CaMKIIa neurons contribute to wakefulness. Then in millisecond-scale control of neuronal activity, short-term and long-term optogenetic activation induced the initiation and maintenance of wakefulness, respectively. We also observed that mice reduced exploratory behaviors in classic anxiety tests while activating the VMH CaMKIIa neurons and were anxiolytic while inhibiting. Additionally, photostimulation of the VMH CaMKIIa axons in the paraventricular hypothalamus (PVH) mediated wakefulness and triggered anxiety-like behaviors as well. In conclusion, our results demonstrate that the VMH participates in the control of wakefulness and anxiety, and offer a neurological explanation for insomnia and anxiety, which may be valuable for therapeutic interventions such as medication and transcranial magnetic stimulation.
Assuntos
Distúrbios do Início e da Manutenção do Sono , Vigília , Camundongos , Animais , Vigília/fisiologia , Hipotálamo , Neurônios/metabolismo , AnsiedadeRESUMO
Activating transcription factor 6 (ATF6) is an endoplasmic reticulum (ER) stress-regulated transcription factor that induces expression of major molecular chaperones in the ER. We recently reported that ATF6ß, a subtype of ATF6, promoted survival of hippocampal neurons exposed to ER stress and excitotoxicity, at least in part by inducing expression of calreticulin, an ER molecular chaperone with high Ca2+-binding capacity. In the present study, we demonstrate that ATF6ß deficiency in mice also decreases calreticulin expression and increases expression of glucose-regulated protein 78, another ER molecular chaperone, in emotional brain regions such as the prefrontal cortex (PFC), hypothalamus, hippocampus, and amygdala. Comprehensive behavioral analyses revealed that Atf6b-/- mice exhibit anxiety-like behavior in the light/dark transition test and hyperactivity in the forced swim test. Consistent with these results, PFC and hypothalamic corticotropin-releasing hormone (CRH) expression was increased in Atf6b-/- mice, as was circulating corticosterone. Moreover, CRH receptor 1 antagonism alleviated anxiety-like behavior in Atf6b-/- mice. These findings suggest that ATF6ß deficiency produces anxiety-like behavior and hyperactivity via a CRH receptor 1-dependent mechanism. ATF6ß could play a role in psychiatric conditions in the emotional centers of the brain.
Assuntos
Calreticulina , Receptores de Hormônio Liberador da Corticotropina , Camundongos , Animais , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Calreticulina/metabolismo , Hormônio Liberador da Corticotropina/metabolismo , Hipotálamo/metabolismo , Ansiedade/metabolismo , Corticosterona/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Estresse Psicológico/complicações , Estresse Psicológico/metabolismo , Fator 6 Ativador da Transcrição/metabolismoRESUMO
BACKGROUND: Mild hypoxic-ischemic encephalopathy (HIE) is a condition that predisposes to negative outcomes such as neuroanatomical injury, mood disorders, and motor or cognitive disabilities. The neuroinflammation plays an important role in the neurological damage; therefore, reducing it could provide neuroprotection. The leuprolide acetate (LA) has shown to have neuroregenerative and immunomodulator properties in other nervous system injuries. OBJECTIVE: The aim of this study was to evaluate the immunomodulatory effect of LA in the acute phase of mild HIE and its effects in motor activity and behavior in a subacute phase. METHOD: Forty-five Wistar rats on postnatal day 7 were divided into Sham, HIE treated with saline solution (HIE-SS), and HIE-LA. The HIE was performed cutting of the right carotid artery followed by 60 min of hypoxia. The expression of the inflammatory cytokines interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and the chemokine CXCL-1 were evaluated 72 h after HIE by RT-qPCR and the motor activity and behavior were evaluated by open field test at postnatal day 33. RESULTS: HIE-SS animals showed increased expression of IL-1ß, TNF-α, IFN-γ, and CXCL-1 genes in injured tissue. However, the HIE-LA group exhibited similar expression levels of IL-1ß and TNF-α to the Sham group, while IFN-γ and CXCL-1 mRNA expression were attenuated with LA treatment. LA treatment also prevented anxiety-like behavior in the open field test. CONCLUSION: Treatment with LA partially reverses HIE-induced neuroinflammation and prevents anxiety-like behavior in neonatal rats.
Assuntos
Hipóxia-Isquemia Encefálica , Animais , Ratos , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/patologia , Animais Recém-Nascidos , Leuprolida/farmacologia , Leuprolida/uso terapêutico , Fator de Necrose Tumoral alfa , Doenças Neuroinflamatórias , Ratos Wistar , Fatores Imunológicos , Ansiedade/tratamento farmacológico , Ansiedade/etiologiaRESUMO
This study aimed to investigate the effect of rosuvastatin treatment on anxiety-related behavior and short- and long-term memory impairment in mice infected with acute RH and BRI strains of Toxoplasma gondii. Balb/C mice were infected intraperitoneally and after 2 h, oral treatment with rosuvastatin (40 mg/kg/day) was initiated for 4 days. Behaviors related to anxiety and locomotion were evaluated in the open field (OF), and short- and long-term memory through the novel object recognition test (NOR). At the end of the experiments, peritoneal fluid, brain, liver, and lung were collected for T. gondii DNA quantification and histopathological analysis. Infection with BRI strain reduced the dwell time and central locomotion in the OF (p < 0.05), indicating anxiogenic type behavior, while treatment with rosuvastatin reversed this response (p < 0.05). RH strain infection did not alter any behavior in the OF (p > 0.05) and both strains impaired short- and long-term memory (NOR test), but with no significant treatment effect (p > 0.05). The BRI strain was shown to be more damaging in relation to anxiogenic type behavior when compared to the RH strain (p < 0.05), whereas rosuvastatin reduced this damaging effect in BRI. The treatment reduced the parasite load in the peritoneal lavage, liver, and lung of animals infected with both acute strains; however, it significantly (p < 0.05) attenuated the inflammatory process only in BRI-infected and treated animals, showing that non-archetypal genotypes are more damaging in rodents. This suggests that rosuvastatin may be a drug with great therapeutic potential against T. gondii mainly to reduce damage from virulent strains.
Assuntos
Toxoplasma , Animais , Camundongos , Rosuvastatina Cálcica/uso terapêutico , Brasil , Inflamação/tratamento farmacológico , Camundongos Endogâmicos BALB CRESUMO
Animal models are crucial to understanding the mechanisms underlying the deleterious consequences of early-life stress. Here, we aimed to examine the effect of the limited bedding nesting (LBN) paradigm on early life development milestones and anxiety- and/or depression-like behavior in adolescent and adult mice from two inbred mice of both sexes. C57BL/6NCrl and BALB/c litters were exposed to the LBN paradigm postnatal day (PND) 2-9. Maternal behavior recording occurred on PND 3-9, and pups were weighed daily and examined to verify the eye-opening on PND 10-22. The male and female offspring underwent evaluation in the open field test, elevated plus-maze, and the forced swimming test during adolescence (PND 45-49) and adulthood (PND 75-79). We found that LBN impaired the maternal behavior patterns of both strain dams, mainly on C57BL/6NCrl strain. Also, LBN delayed the pup's eye-opening time and reduced body weight gain, impacting C57BL/6NCrl pups more. We also found that LBN decreased anxiety-related indices in adolescent and adult male but not female mice of both strains. Furthermore, LBN decreased depression-related indices only adolescent female and male BALB/c and female but not male C57BL/6NCrl mice. These findings reinforce the evidence that the LBN paradigm impairs the maternal behavior pattern and pup's early developmental milestones but does not induce anxiety- or depressive-like behavior outcomes during later life.