Neuroscience
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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.
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This study aims to investigate the changes in the topological organization of WM functional connectivity in individuals with TAO, providing a novel and insightful perspective on the functional disruptions that characterize this condition. ⋯ In our study, we found that patients with TAO exhibited abnormalities in the white matter functional network regarding small-world metrics and modularity, which are related to visual and cognitive functions.
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Radiation-induced cognitive impairment (RICI) and emotional disorder (RIED) are comorbidity which seriously affect the quality of life in radiation-induced brain injury (RIBI) patients. ⋯ RICI intensively occurred in post-irradiation middle stage and progressed to late stage while RIED occurred mostly in late stage in RIBI. Consistency of RICI and RIED development process was observed.
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Review
Cross-species dissection of the modular role of the ventral tegmental area in depressive disorders.
Depressive disorders, including major depressive disorder (MDD), represent one of the most prevalent set of disorders worldwide. MDD is characterized by a range of cognitive, behavioral, and neurobiological changes that contribute to the vast array of symptom profiles that make this disorder particularly difficult to treat. A multitude of established evidence suggests a role for the dopamine system, stemming in part from the ventral tegmental area (VTA), in mediating symptoms and behavioral changes that underlie depression. ⋯ Then, we introduce the role of the VTA in reward processing as it compares to aversion processing. Next, we characterize distinct neural pathways within the VTA circuitry to understand the effects of chronic social and non-social stress and tie together how these neurobiological changes manifest into specific behavioral phenotypes. Finally, we relate these preclinical findings to clinical findings to parse the heterogeneity of depressive phenotypes and explain the efficacy of recent novel pharmacological interventions that may target the VTA in MDD.
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The purpose of this study was to examine variations in gut microbes and their metabolites between patients with original and recurrent stroke, providing insights and justification for the diagnosis and prevention of ischemic stroke progression from the perspective of the gut microbiota-metabolite-brain axis. ⋯ Compared with the Os, Rs was mainly characterized by severe destruction of anaerobic bacteria and significant depletion of SCFAs-producing bacteria. In addition, the related compounds involved in arachidonic acid metabolism and linoleic acid metabolism pathway may be biomarkers related to ischemic stroke progression.