Neuroscience
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Neuroinflammation can be directly linked to the imbalance in the Kynurenine-tryptophan Pathway (KP) metabolism. Under inflammatory circumstances, the KP is activated, resulting in a rise in the KP metabolite L-kynurenine (KYN) in the peripheral and central nervous systems (CNS). Increased amounts of KYN in the brain may lead to neurotoxic KYN metabolites, mostly due to breakdown by Kynurenine-3-monooxygenase (KMO). ⋯ The neurobehavioural assessment involving elevated plus-maze, sucrose preference test, line crossing, and actophotometer revealed that the test drug is capable of decreasing LPS-induced anxiety, depression, and anhedonia at both low and high doses respectively. The histopathological analysis indicated that the neurodegeneration is attenuated at high doses of Tetrahydrocoptisine. A test drug demonstrated potency in inhibiting Kynurenine monooxygenase (KMO) expression in the brain, leading to reduced levels of nitric oxide and lipid peroxidation compared to a control group.
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A decline in mitochondrial functions associated with ageing is the key factor of free radical generation which contributes to age-related pathologies. Protecting healthy functional mitochondrial networks with antioxidants is critical in promoting healthy ageing. This study aimed to investigate the protective effect of ergothioneine (EGT)-rich Lentinula edodes extract (LE-ETH) against tert-butyl hydroperoxide (t-BHP) assaulted senescent HT22 cells. ⋯ A total of 23 compounds consisting of phenols, fatty acids, and sterols were identified in the ethanolic extract. Pentanoic acid was the major compound identified in LE-ETH. These findings demonstrated that EGT-rich L.edodes mushroom is a potential neuroprotective agent which could serve as a potential therapeutic strategy for the preservation of mitochondrial functions in healthy ageing explorations.
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The trigeminal ganglion (TG) comprises primary sensory neurons responsible for orofacial sensations, subsequently projecting to the trigeminal nuclei in the brainstem. However, the circuit basis of nasal mechanosensation is not well characterized. Here we elucidate the anatomical organization of both peripheral and central projections of the TG. ⋯ In contrast, the MrgprD+ neurons only densely project to outer edge of Sp5C. In addition, we further determined the ascending pathway of the TG neurons. Taken together, our study demonstrates the peripheral and central projection pattern of mechanosensory neurons in the TG, which provides a basis for the future functional studies.
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Attention deficit hyperactivity disorder (ADHD) is one of the most frequent and disabling neurodevelopmental disorders. Recent research on cerebral blood flow (CBF) has enhanced understanding of the underlying pathophysiology in neuropsychiatric disorders. This systematic review aims to synthesize the existing literature on CBF anomalies among individuals with ADHD in comparison to controls. ⋯ This review highlights diverse CBF anomalies in ADHD. The most consistently reported findings suggest hypoperfusion during resting state in prefrontal and temporal areas, along with the basal ganglia, while there is a hyperperfusion in frontal, parietal and occipital regions. Further research, including longitudinal studies, is essential to develop a comprehensive understanding of CBF implications in ADHD.
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Incidences of seizure after e-cigarette use in adolescents and young adults have been reported, raising the concern about the risk of nicotine overconsumption. Few previous studies have investigated the effects of nicotine at high doses on brain and behavior in adolescent animals. In this study, the effects of a 15-day repeated nicotine treatment at a daily dose of 2 mg/kg body weight were investigated in adolescent and adult male rats. ⋯ Only the nicotine-treated adolescents showed significant changes in brain anatomy 1 day post-treatment, which manifested as a significant reduction of whole-brain gray matter (GM) volume, a further reduction of regional GM volume in the medial prefrontal cortex (mPFC) and altered GM volume covariations between the mPFC and a number of brain regions. The mPFC of nicotine-treated adolescent rats did not exhibit evident signs of neuronal degeneration and reactive astrocytosis, but showed a significantly decreased expression of presynaptic marker synaptophysin (SYN), along with a significantly increased oxidative stress and a significantly elevated expressions of microglial marker ionized calcium binding adaptor molecule 1 (IBA1). Together, these results suggested that repeated nicotine overdosing may shift regional redox, modulate microglia-mediated pruning, and give rise to structural/connectivity deficits in the mPFC of adolescent male rats.