Neuroscience
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Kainic acid (KA), an analogue of the excitatory neurotransmitter glutamate, when administered systemically can trigger seizures and neuronal loss in a manner that mirrors the neuropathology of human mesial temporal lobe epilepsy (mTLE), which affects ∼50 million people globally. Evidence suggests that changes in astrocytes which precede neuronal damage play an important role in the degeneration of neurons and/or development of seizures in TLE pathogenesis. Additionally, a role for microtubule associated tau protein, involved in various neurodegenerative diseases including Alzheimer's disease, has also been suggested in the development of seizure and/or neurodegeneration in TLE pathogenesis. ⋯ Concurrently, the total (Tau1 and Tau5) and phospho-tau (AT270 and PHF1) levels are transiently enhanced following KA administration. Furthermore, the level/expression of cleaved-tau, which is apparent in a subset of GFAP-, S100B- and A2-positive astrocytes, are increased in KA-treated rats. These results, taken together, suggest a differential role for various astrocytic subpopulations and tau protein in the development of seizure and/or loss of neurons in KA model of TLE and possibly in human mTLE pathogenesis.
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Walking is an important function which requires coordinated activity of sensory-motor neural networks. Noninvasive brain stimulation (NIBS) is a safe neuromodulatory technique with motor function-improving effects. This study aimed to determine the effect of different types of NIBS interventions explored in randomized controlled trials on gait in healthy young and older adults. ⋯ NIBS is a promising approach to improve gait in healthy young and older adults. Anodal tDCS over the motor areas and DLPFC, and tACS over the cerebellum have shown positive effects on gait.
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Postoperative cognitive dysfunction (POCD) is characterized by impaired cognitive function, such as decreased learning and memory after anesthesia and surgery. This study aimed to explore the effect of luteoloside, a flavonoid extracted from natural herbs, on sevoflurane-induced cognitive dysfunction. Aged Sprague-Dawley male rats (20 months old) were treated with luteoloside for 7 days prior to sevoflurane exposure. ⋯ Notably, silencing Opa1 blocked the protective effect of luteoloside on hippocampal neurons and mitochondrial function. In summary, luteoloside prevented sevoflurane-induced cognitive dysfunction in aged rats, which may be achieved by regulating mitochondrial dynamics. Our study reveals the potential of luteoloside in preventing POCD in aged patients.
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Years before Alzheimer's disease (AD) is diagnosed, patients experience an impaired sense of smell, and β-amyloid plaques accumulate within the olfactory mucosa and olfactory bulb (OB). The olfactory vector hypothesis proposes that external agents cause β-amyloid to aggregate and spread from the OB to connected downstream brain regions. To reproduce the slow accumulation of β-amyloid that occurs in human AD, we investigated the progressive accumulation of β-amyloid across the brain using a conditional mouse model that overexpresses a humanized mutant form of the amyloid precursor protein (hAPP) in olfactory sensory neurons. ⋯ We also observe reduced OB volumes in these mice when hAPP expression begins prior-to but not post-weaning which we tracked using manganese-enhanced MRI. We therefore conclude that the reduced OB volume does not represent progressive degeneration but rather disrupted OB development. Overall, our data demonstrate that hAPP expression in the olfactory epithelium can lead to the accumulation and spread of β-amyloid through the olfactory system into the hippocampus, consistent with an olfactory system role in the early stages of β-amyloid-related AD progression.
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In this study, the relationships between lifestyle behaviors within the scope of neuroplasticity and neurogenesis approach and depression, anxiety and neuropsychological test scores were examined. As this study aimed to reveal the relationships between events or variables, it was designed using the "descriptive cross-sectional study" method, one of descriptive and relational research methods, was used. The data were collected from 117 students by the researchers using the Öktem Verbal Memory Test, WCST, Digit Span Test, Beck Depression Inventory, Beck Anxiety Scale and Lifestyle Behaviors Survey. ⋯ Moreover, those with good levels of sleep quality, social interaction and nutrition had significantly lower depression scores. Both depression and anxiety scores of those who did sport/exercise, which was among the lifestyle behaviors, were found to be significantly lower. Lastly, the correlations between the neuropsychological test scores and the depression and anxiety scores were examined, and a significant positive correlation was found between both depression and anxiety scores and the "failure to maintain set" scores.