摘要:MicroRNAs are small non-coding RNAs that play crucial roles in the regulation of gene expression an...MicroRNAs are small non-coding RNAs that play crucial roles in the regulation of gene expression and protein synthesis during brain development. MiR-3099 is highly expressed throughout embryogenesis, especially in the developing central nervous system. Moreover, miR-3099 is also expressed at a higher level in differentiating neurons in vitro, suggesting that it is a potential regulator during neuronal cell development. This study aimed to predict the target genes of miR-3099 via in-silico analysis using four independent prediction algorithms(miRDB,miRanda, Target Scan, and DIANA-micro-T-CDS) with emphasis on target genes related to brain development and function. Based on the analysis, a total of 3,174 miR-3099 target genes were predicted. Those predicted by at least three algorithms(324 genes) were subjected to DAVID bioinformatics analysis to understand their overallfunctional themes and representation. The analysis revealed that nearly 70% of the target genes were expressed in the nervous system and a significant proportion were associated with transcriptional regulation and protein ubiquitination mechanisms. Comparison of in situ hybridization(ISH) expression patterns of miR-3099 in both published and in-house-generated ISH sections with the ISH sections of target genes from the Allen Brain Atlas identified 7 target genes(Dnmt3a, Gabpa, Gfap, Itga4,Lxn, Smad7, and Tbx18) having expression patterns complementary to miR-3099 in the developing and adult mouse brain samples. Of these, we validated Gfap as a direct downstream target of miR-3099 using the luciferase reporter gene system. In conclusion, we report the successful prediction and validation of Gfap as an miR-3099 target gene using a combination of bioinformatics resources with enrichment of annotations based on functional ontologies and a spatio-temporal expression dataset.显示全部
摘要:It is disputed whether those neurons in the primary motor cortex(M1) that encode hand orientation c...It is disputed whether those neurons in the primary motor cortex(M1) that encode hand orientation constitute an independent channel for orientation control in reach-to-grasp behaviors. Here, we trained two monkeys to reach forward and grasp objects positioned in the frontal plane at different orientation angles, and simultaneously recorded the activity of M1 neurons. Among the 2235 neurons recorded in M1, we found that 18.7% had a high correlation exclusively with hand orientation, 15.9% with movement direction, and 29.5% with both movement direction and hand orientation. The distributions of neurons encoding hand orientation and those encoding movement direction were not uniform but coexisted in the same region. The trajectory of hand rotation was reproduced by the firing patterns of the orientation-related neurons independent of the hand reaching direction. These resultssuggest that hand orientation is an independent component for the control of reaching and grasping activity.显示全部
摘要:Activation of presynaptic group II metabotropic glutamate receptors(mGluR2/3) inhibits drug reward ...Activation of presynaptic group II metabotropic glutamate receptors(mGluR2/3) inhibits drug reward and drug-seeking behavior, but the role of N-acetylaspartylglutamate(NAAG), an agonist of endogenous mGluR2/3,in heroin reward and heroin-seeking behavior remained unclear. Here, we aimed to explore the effects of exogenous NAAG on heroin self-administration and heroinseeking behavior. First, rats were trained to self-administer heroin under a fixed ratio 1(FR1) schedule for 10 days,then received NAAG(50 or 100μg/10 μL in each nostril)in the absence or presence of LY341495(1 mg/kg, i.p.), an antagonist of mGluR2/3, on day 11 and the effects of NAAG on heroin self-administration under FR1 were recorded for 3 consecutive days. Motivation was assessed in heroin self-administration under a progressive ratio schedule on day 11 in another 5 groups with the same doses of NAAG. Additional rats were withdrawn for 14 days after 14 days of heroin self-administration, then received the same pharmacological pretreatment and were tested for heroin-seeking behaviors induced by heroin priming or cues. The results showed that intranasal administration of NAAG significantly decreased intravenous heroin selfadministration on day 12, but not on day 11. Pretreatment with LY341495 prior to testing on day 12 prevented the inhibitory effect of NAAG on heroin reinforcement. The break-point for reward motivation was significantly reduced by NAAG. Moreover, NAAG also significantly inhibited the heroin-seeking behaviors induced by heroinpriming or cues and these were restored by pretreatment with LY341495. These results demonstrated that NAAG,via activation of presynaptic mGluR2/3, attenuated the heroin reinforcement, heroin motivational value, and heroin-seeking behavior, suggesting that it may be used as an adjunct treatment for heroin addiction.显示全部
摘要:Accumulation and aggregation of β-amyloid(Aβ) peptides result in neuronal death, leading to cogni...Accumulation and aggregation of β-amyloid(Aβ) peptides result in neuronal death, leading to cognitive dysfunction in Alzheimer’s disease. The self-assembled Aβ molecules form various intermediate aggregates including oligomers that are more toxic to neurons than the mature aggregates, including fibrils. Thus, one strategy to alleviate Aβ toxicity is to facilitate the conversion of Aβ intermediates to larger aggregates such as fibrils. In this study, we designed a peptide named A3 that significantly enhanced the formation of amorphous aggregates of Aβ by accelerating the aggregation kinetics. Thioflavin T fluorescence experiments revealed an accelerated aggregation of Aβ monomers, accompanying reduced Aβ cytotoxicity. Transgenic Caenorhabditis elegans over-expressing amyloid precursor protein exhibited paralysis due to the accumulation of Aβ oligomers, and this phenotype was attenuated by feeding the animals with A3 peptide. These findings suggest that the Aβ aggregation-promotion effect can potentially be useful for developing strategies to reduce Aβ toxicity.显示全部
摘要:The thalamus and central dopamine signaling have been shown to play important roles in high-level c...The thalamus and central dopamine signaling have been shown to play important roles in high-level cognitive processes including impulsivity. However, little is known about the role of dopamine receptors in the thalamus in decisional impulsivity. In the present study,rats were tested using a delay discounting task and divided into three groups: high impulsivity(HI), medium impulsivity(MI), and low impulsivity(LI). Subsequent in vivo voxel-based magnetic resonance imaging revealed that the HI rats displayed a markedly reduced density of gray matter in the lateral thalamus compared with the LI rats. In the MI rats, the dopamine D1 receptor antagonist SCH23390 or the D2 receptor antagonist eticlopride was microinjected into the lateral thalamus. SCH23390 significantly decreased their choice of a large, delayed reward and increased their omission of lever presses. In contrast,eticlopride increased the choice of a large, delayed reward but had no effect on the omissions. Together, our results indicate that the lateral thalamus is involved in decisional impulsivity, and dopamine D1 and D2 receptors in the lateral thalamus have distinct effects on decisional impulsive behaviors in rats. These results provide a new insightinto the dopamine signaling in the lateral thalamus in decisional impulsivity.显示全部
摘要:Itch(pruritus) is one of the most disabling syndromes in patients suffering from skin, liver, or ki...Itch(pruritus) is one of the most disabling syndromes in patients suffering from skin, liver, or kidney diseases. Our previous study highlighted a key role of oxidative stress in acute itch. Here, we evaluated the effects of antioxidants in mouse models of acute and chronic itch and explored the potential mechanisms. The effects of systemic administration of the antioxidants N-acetyl-Lcysteine(NAC) and N-tert-butyl-a-phenylnitrone(PBN)were determined by behavioral tests in mouse models of acute itch induced by compound 48/80 or chloroquine, and chronic itch by treatment with a mixture of acetonediethyl-ether-water. We found that systemic administration of NAC or PBN significantly alleviated compound 48/80-and chloroquine-induced acute itch in a dose-dependent manner, attenuated dry skin-induced chronic itch, and suppressed oxidative stress in the affected skin.Antioxidants significantly decreased the accumulation of intracellular reactive oxygen species directly induced by compound 48/80 and chloroquine in the cultured dorsal root ganglia-derived cell line ND7-23. Finally, the antioxidants remarkably inhibited the compound 48/80-induced phosphorylation of extracellular signal-regulated kinase in the spinal cord. These results indicated that oxidative stress plays a critical role in acute and chronic itch in the periphery and spinal cord and antioxidant treatment may be a promising strategy for anti-itch therapy.显示全部
摘要:The protein composition of cerebrospinal fluid(CSF) in neural tube defects(NTDs) remains unknown. W...The protein composition of cerebrospinal fluid(CSF) in neural tube defects(NTDs) remains unknown. We investigated the protein composition of CSF from 9 infants with NTDs using isobaric tags for relative and absolute quantitation(iTRAQ). We identified 568 proteins in the CSF of infants with spina bifida, which is the most common type of NTD. Among these, 18 proteins were associated with neural tube closure in the CSF during human embryonic neurulation and 5 were involved in NTDs. Based on these results, an animal model was further utilized to investigate early serum biomarkers for NTDs.We found that the myristoylated alanine-rich C-kinase substrate, Kunitz-type protease inhibitor 2, andapolipoprotein B-100 protein levels were decreased in both embryos and the sera of pregnant Sprague-Dawley rats carrying embryos with NTDs. CSF proteins may be useful in the discovery of potential serum biomarkers for NTDs.显示全部
摘要:Schizophrenia is considered to be a disorder of brain connectivity, which might result from a dispr...Schizophrenia is considered to be a disorder of brain connectivity, which might result from a disproportionally impaired rich-club organization. The rich-club is composed of highly interconnected hub regions that play crucial roles in integrating information between different brain regions. Few studies have yet investigated whether the structural rich-club organization is impaired in patients and their first-degree relatives. In this study, we established a weighted network model of white matter connections using diffusion tensor imaging of 19 patients and 39 unaffected parents, 22 young healthy controls for the patients, and 25 old healthy controls for the parents. Feeder edges between rich-club nodes and non-rich-club nodes were significantly decreased in both schizophrenic patients and their unaffected parents compared with controls.Furthermore, the feeder edges showed significant positive correlations with the scores in Category Fluency Test—animal naming in the unaffected parents. Specific feeder edges exhibited discriminative power with accuracy of 84.4% in distinguishing unaffected parents from old healthy controls. Our findings suggest that impaired richclub organization, especially impaired feeder edges, may be related to familial vulnerability to schizophrenia,possibly reflecting a genetic predisposition for schizophrenia.显示全部
摘要:Ion channels are crucial in the generation and modulation of excitability in the nervous system and...Ion channels are crucial in the generation and modulation of excitability in the nervous system and have been implicated in human epilepsy. Forty-one epilepsyassociated ion channel genes and their mutations are systematically reviewed. In this paper, we analyzed the genotypes, functional alterations(funotypes), and phenotypes of these mutations. Eleven genes featured loss-offunction mutations and six had gain-of-function mutations.Nine genes displayed diversified funotypes, among which a distinct funotype-phenotype correlation was found in SCN1A. These data suggest that the funotype is an essential consideration in evaluating the pathogenicity of mutations and a distinct funotype or funotype-phenotype correlation helps to define the pathogenic potential of a gene.显示全部
摘要:<正>Human brain development is a complex process that continues between birth and maturity,and moni...<正>Human brain development is a complex process that continues between birth and maturity,and monitoring the underlying maturational changes at these stages is crucial for our understanding of typical development as well as neurodevelopmental disorders.During the critical periods of brain development,on one hand,many human capacities originate,but on the other hand,a brain undergoing rapid显示全部