Neuroscience
-
Traumatic brain injury (TBI) is a public health problem that causes high mortality and disability worldwide. Secondary brain damage from this type of injury may cause brain edema, blood-brain barrier destruction, and neurological dysfunction. MicroRNAs (miRNAs) are a class of small non-coding RNAs that regulate gene expression at the post-transcriptional level and play vital roles in maintaining and regulating physiological function. ⋯ Some special miRNAs in blood were used in clinical trials for TBI diagnosis and prognosis prediction. Treatment with miRNA agomirs or antagomirs alleviated the lesion volume and improved neurological deficits post-injury. We review the current progress of miRNA studies in TBI patients and animal models and identify the prospects and difficulties involved in the clinical applications of miRNAs.
-
Parkinson's disease is a debilitating neurodegenerative movement disorder, characterized by the progressive and selective loss of dopaminergic neurons located in the substantia nigra, leading to clinical motor symptoms. The factors involved in PD are rather multifaceted. There are many cellular pathways contributing to its neuro-pathogenesis, which include abnormal protein aggregation, impaired ubiquitin proteasome system, autophagy, and neuroinflammation. ⋯ Since they somewhat modulate many mRNA targets simultaneously, many cellular pathways may be affected by one individual miRNA. Moreover, miRNAs can stably circulate in cerebrospinal fluid and blood, and their expression pattern can reflect the molecular pathophysiology, thus making them promising biomarkers in PD diagnosis and prognosis. In this review, we will review the recent progress on miRNA's mechanism in PD pathogenesis and discuss the possibilities of miRNAs as PD molecular biomarkers.
-
In this paper, by utilizing surface diffeomorphic deformations, we constructed and analyzed subcortical shape morphometric networks in 210 healthy control (HC) subjects and 175 subjects with Alzheimer's disease (AD), aiming to identify AD-induced abnormalities in the subcortical shape network. We quantitatively analyzed pertinent network attributes of the entire network and each node. Further to this, hierarchical analyses were performed; group comparisons were conducted at the structure level first and then the sub-region level. ⋯ In addition, the local nodal efficiencies between the right thalamus and all three of the right hippocampus, right amygdala, and left thalamus, as well as that between the left amygdala and left hippocampus, decreased significantly in AD. According to the sub-regional network analyses, we observed significant AD-induced local efficiency decreases between different sub-regions within the right hippocampus itself and between the subiculum of the right hippocampus and the sub-region of the right thalamus connecting to the temporal lobe, indicating a degradation of circuit between the hippocampus, thalamus, and temporal lobe. Statistical comparisons were performed using 40,000 non-parametric permutation tests, with false discovery rate correction employed for multiple comparison correction.
-
Extensive studies have indicated brain function connectivity abnormalities in autism spectrum disorder (ASD). However, there is a lack of longitudinal or cross-sectional research focused on tracking age-related developmental trends of autistic children at an early stage of brain development or based on a relatively large sample. The present study examined brain network changes in a total of 186 children both with and without ASD from 3 to 11 years, an early and key development period when significant changes are expected. ⋯ The main findings of the study were as follows: (1) From the connectivity analysis, several inter-regional synchronizations with reduction were identified in the younger and older ASD groups, and several intra-regional synchronization increases were observed in the older ASD group. (2) From the graph analysis, a reduced clustering coefficient and enhanced mean shortest path length in specific frequencies was observed in children with ASD. (3) Results suggested an age-related decrease of the mean shortest path length in the delta and theta bands in TD children, whereas atypical age-related alteration was observed in the ASD group. In addition, graph measures were correlated with ASD symptom severity in the alpha band. These results demonstrate that abnormal neural communication is already present at the early stages of brain development in autistic children and this may be involved in the behavioral deficits associated with ASD.
-
Sex differences in social cognitive ability are well established, including measures of Theory of Mind (ToM). The aim of this study was to investigate if sex mediates the effects of high-definition transcranial direct current stimulation (HD-tDCS) administered to a key hub of the social brain (i.e., the dorsomedial prefrontal cortex, dmPFC) on the Reading the Mind in the Eyes Test (RMET). Forty healthy young adults (18-35 years) were randomly allocated to receive either anodal or cathodal HD-tDCS in sham HD-tDCS controlled, double blind designs. ⋯ The current study is the first to show improved performance on the RMET after tDCS to the dmPFC in females only. The polarity-specific effects and use of focal HD-tDCS provide evidence for sex-dependent differences in dmPFC function in relation to the RMET. Future studies using tDCS to study or improve ToM, need to consider sex.