Neuroscience
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Glioma, one of the most common cancers in human, is classified to different grades according to the degrees of malignancy. Glioblastoma (GBM) is known to be the most malignant (Grade IV) whereas low-grade astrocytoma (LGA, Grade II) is relatively benign. The mechanism underlying the pathogenesis and progression of glioma malignancy remains unclear. ⋯ Interaction network analysis indicated that the GBM-associated proteins in the RNA processing were linked to crucial signaling transduction modulators including epidermal growth factor receptor (EGFR), signal transducer and activator of transcription 1 (STAT1), and mitogen-activated protein kinase 1 (MAPK1), which were further connected to the proteins important for neuronal structural integrity, development and functions. Upregulation of 40S ribosomal protein S5 (RPS5), Ferritin Heavy chain (FTH1) and STAT1, and downregulation of tenascin R (TNR) were validated as representatives by immune assays. In summary, we revealed a panel of GBM-associated proteins and the important modulators centered at the RNA-processing network in glioma malignancy that may become novel biomarkers and help elucidate the underlying mechanism.
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Semaphorins comprise a family of proteins involved in axon guidance during development. Semaphorin4D (Sema4D) has both neuroregenerative and neurorepressive functions, being able to stimulate both axonal outgrowth and growth cone collapse during development, and therefore could play an important role in neurological recovery from traumatic injury. Here, we used a zebrafish spinal cord transection model to study the role of Sema4D in a system capable of neuroregeneration. ⋯ Anterograde and retrograde tracing indicate that Sema4D participates in axon regeneration in the spinal cord following spinal cord injury (SCI) in the zebrafish. Swim tracking shows that MO-mediated inhibition of Sema4D retarded the recovery of swimming function when compared to standard control MO. The combined results indicate that Sema4D expression in motoneurons enhances locomotor recovery and axon regeneration, possibly by regulating microglia function, after SCI in adult zebrafish.
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Conduct disorder (CD) is a developmental disorder defined by a repetitive and persistent display of antisocial and aggressive behaviors that violates the rights of others or basic social rules. Recently, resting-state functional magnetic resonance imaging (rsfMRI) has been widely adopted to investigate the altered intrinsic neural activities and the disrupted endogenous brain connectivity of CD. In this study, functional connectivity density (FCD) mapping, a newly developed ultrafast voxel-wise method based on rsfMRI, was applied for the first time to examine the changes in the brain functional connectivity in CD at the voxel level. ⋯ We discovered that compared to healthy controls, CD patients showed increased short-range FCD in the default-mode network including the bilateral posterior cingulate cortex (PCC) and the bilateral precuneus (PCUN). More importantly, increased short-range FCD values in the bilateral PCC, the bilateral PCUN, and increased long-range FCD values in the left MCC showed significant correlations with the impulsivity. Overall, these results suggested that the FCD abnormalities in CD patients occurred in brain regions known to be involved in cognition, emotion and visual perception.
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Transgenic knock-in (KI) mice that express CaV2.1 channels containing an R192Q gain-of-function mutation in the α1A subunit known to cause familial hemiplegic migraine type-1 in patients, exhibit key disease characteristics and provide a useful tool to investigate pathophysiological mechanisms of pain transduction. Previously, KI trigeminal sensory neurons were shown to exhibit constitutive hyperexcitability due to up-regulation of ATP-gated P2X3 receptors that trigger spike activity at a more negative threshold. This implies that intrinsic neuronal conductances may shape action potential generation in response to ATP, which could act as a mediator of migraine headache. ⋯ In KI TG neurons, HCN2 subunits were predominantly present in the cytoplasm, not at the plasma membrane, likely accounting for the smaller Ih of such cells. ZD7288 hyperpolarized the membrane potential, thereby raising the firing threshold, and prolonging the spike trajectory to generate fewer spikes due to P2X3 receptor activation. The low amplitude of Ih in KI TG neurons suggests that down-regulation of Ih current in sub-threshold behavior acts as a compensatory mechanism to limit sensory hyperexcitability, manifested under certain stressful stimuli.
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Exposure to acute stress leads to diverse changes, which include either beneficial or deleterious effects on molecular levels that are implicated in stress-related disorders. N-methyl-d-aspartate receptor (NMDAR)-mediated signalings, are thought to be vital players in stress-related mental disorders as well as attractive therapeutic targets for clinical treatment. In the present study, we utilized acute stress models in mice to explore regulation of phosphorylation level of S1284 in GluN2B subunit of NMDAR. ⋯ Moreover, phosphorylation change of S1284 was negated by treatment of roscovitine which is believed to be a Cyclin-dependent kinase inhibitor. Besides, we showed well correlation of phosphorylation change of S1284 and immobility time during forced swimming. Collectively, our results demonstrated that phosphorylation level of S1284 in GluN2B was regulated by acute stress.