Neuroscience
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Growing evidence indicates that GABAergic interneurons play a pivotal role to generate brain oscillation patterns, which are fundamental for the mnemonic processing of the hippocampus. While acetylcholine (ACh) is a powerful modulator of synaptic plasticity and brain function, few studies have been focused on the role of cholinergic signaling in the regulation of GABAergic inhibitory synaptic plasticity. ⋯ These forms of iLTP are blocked by the M1 type of mAChR (MR1) or by the group I of mGluR (mGluR1/5) antagonists. These results suggest the existence of spatiotemporal cooperativity between cholinergic and glutamatergic pathways where activation of mAChR serves as a metaplastic switch making glutamatergic synapses capable to induce long-term potentiation at inhibitory synapses, that may contribute to the modulation of brain mechanisms of learning and memory.
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Quercetin is a bioactive flavonoid which abundantly exists in vegetables and fruits. Quercetin exerts a neuroprotective effect against cerebral ischemia. Thioredoxin acts as antioxidant by regulating redox signaling. ⋯ However in thioredoxin-silenced cortical neuron, anti-apoptotic effect of quercetin was decreased. Thus, changes of thioredoxin expression by quercetin may contribute to the neuroprotective effect of quercetin in focal cerebral ischemia. Our findings suggest that quercetin mediates its neuroprotective function by regulation of thioredoxin expression and maintenance of interaction between ASK1 and thioredoxin.
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Permanently stored memories become labile through a process called reactivation. Once reactivated, these memories need reconsolidation to become permanent. Sleep is critical for memory consolidation. ⋯ Percent time spent in freezing was monitored during FC, FR and FMR. Our results suggested that as compared to sleeping controls, mice with sleep loss immediately after FR displayed a significant reduction in percent time freezing during FMR. These results suggest that sleep loss may prevent memory reconsolidation.
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Maternal deprivation (MD) in rodents is used to simulate human-infant early life stress, which leads to neural, hormonal, and behavioral alterations. Palatable food (PF) can reduce the stress response, and individuals use it as a self-applied stress relief method. Thus, the present study aimed to evaluate the effect of the association between MD in the early life (P1-P10) and PF consumption (condensed milk, P21-P44) in the central neuroplasticity (BDNF/NGF levels) and central neuroinflammatory parameters (TNF-α, IL-6, and IL-10 levels) in male and female Wistar rats in the adolescence. ⋯ In conclusion, there were more noticeable effects of MD than PF on the variables measured in this study. Sex effect was identified as an important factor and influenced most of the neurochemical measures in this study. In this way, we suggest including both female and male animals in researches to improve the quality of translational studies.
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Major depressive disorders (MDD) and chronic pain (CP) affect significant portion of the world's population and have high comorbidity rate. Social defeat stress (SDS) model was standardized in mice and can trigger depressive-like behavior and chronic pain. Based especially on clinical trials showing an effective preventive and therapeutic effect of physical exercise on CP and symptoms associated with MDD, this study aimed to investigate if the voluntary running wheel exercise can exert these effects in mice submitted to the 10-day SDS protocol, using fluoxetine as positive control. ⋯ Our results showed that the voluntary running wheel exercise was more effective than fluoxetine reversing the SDS-induced persistent hyperalgesia and both, fluoxetine and voluntary running wheel exercise, was effective reversing SDS-induced social avoidance. Also, voluntary running wheel exercise is an effective tool preventing both hyperalgesia and social avoidance induced by SDS. To the best of our knowledge, this was the first study using physical exercise as a therapeutic and preventive tool for chronic pain and depressive-like behavior simultaneously induced by social stress.