Translational Neuroscience最新文献

Background: Death among resuscitated patients is mainly caused by brain injury after cardiac arrest/cardiopulmonary resuscitation (CA/CPR). The angiotensin converting enzyme 2 (ACE2)/angiotensin (Ang)-(1-7)/Mas receptor (MasR) axis has beneficial effects on brain injury. Therefore, we examined the roles of the ACE2/Ang-(1-7)/MasR axis in brain injury after CA/CPR.

Method: We used a total of 76 male New Zealand rabbits, among which 10 rabbits underwent sham operation and 66 rabbits received CA/CPR. Neurological functions were determined by assessing serum levels of neuron-specific enolase and S100 calcium-binding protein B and neurological deficit scores. Brain water content was estimated. Neuronal apoptosis in the hippocampus was assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling assays. The expression levels of various genes were measured by enzyme-linked immunosorbent assay and western blotting.

Results: Ang-(1-7) (MasR activator) alleviated CA/CPR-induced neurological deficits, brain edema, and neuronal damage, and A779 (MasR antagonist) had the opposite functions. The stimulation of ACE2/Ang-(1-7)/MasR inactivated the ACE/Ang II/AT1R axis and activated PI3K/Akt signaling. Inhibiting PI3K/Akt signaling inhibited Ang-(1-7)-mediated protection against brain damage after CA/CPR.

Conclusion: Collectively, the ACE2/Ang-(1-7)/MasR axis alleviates CA/CPR-induced brain injury through attenuating hippocampal neuronal apoptosis by activating PI3K/Akt signaling.

Background: The deposition of Aβ₄₂ has been regarded as one of the important pathological features of Alzheimer's disease (AD). However, drug development for Aβ₄₂ toxicity has been progressed slowly.

Objective: Our aim was to introduce the effect and related mechanism of trehalose on an Aβ_arc (arctic mutant Aβ₄₂) Drosophila AD model.

Methods: The human Aβ_arc was expressed in Drosophila to construct the AD model. Trehalose was added to the culture vial. The movement ability was determined by detecting climbing ability and flight ability. Enzyme-linked immunosorbent assay was used to detect the levels of Aβ_arc, ATP, and lactate. Electron microscopy assay, mitochondrial membrane potential assay, and mitochondrial respiration assay were used to assess the mitochondrial structure and function.

Results: Trehalose strongly improved the movement ability of Aβ_arc Drosophila in a concentration gradient-dependent manner. Furthermore, trehalose increased the content of ATP and decreased the content of Aβ_arc and lactate both in the brain and thorax of Aβ_arc Drosophila. More importantly, the mitochondrial structure and function were greatly improved by trehalose treatment in Aβ_arc Drosophila.

Conclusion: Trehalose improves movement ability at least partly by reducing the Aβ_arc level and restoring the mitochondrial structure and function in Aβ_arc Drosophila.

Background: Both the International Mission for Prognosis and Analysis of Clinical Trials (IMPACT) and the Corticosteroid randomization after significant head injury (CRASH) models are globally acknowledged prognostic algorithms for assessing traumatic brain injury (TBI) outcomes. The aim of this study is to externalize the validation process and juxtapose the prognostic accuracy of the CRASH and IMPACT models in moderate-to-severe TBI patients in the Chinese population.

Methods: We conducted a retrospective study encompassing a cohort of 340 adult TBI patients (aged > 18 years), presenting with Glasgow Coma Scale (GCS) scores ranging from 3 to 12. The data were accrued over 2 years (2020-2022). The primary endpoints were 14-day mortality rates and 6-month Glasgow Outcome Scale (GOS) scores. Analytical metrics, including the area under the receiver operating characteristic curve for discrimination and the Brier score for predictive precision were employed to quantitatively evaluate the model performance.

Results: Mortality rates at the 14-day and 6-month intervals, as well as the 6-month unfavorable GOS outcomes, were established to be 22.06, 40.29, and 65.59%, respectively. The IMPACT models had area under the curves (AUCs) of 0.873, 0.912, and 0.927 for the 6-month unfavorable GOS outcomes, with respective Brier scores of 0.14, 0.12, and 0.11. On the other hand, the AUCs associated with the six-month mortality were 0.883, 0.909, and 0.912, and the corresponding Brier scores were 0.15, 0.14, and 0.13, respectively. The CRASH models exhibited AUCs of 0.862 and 0.878 for the 6-month adverse outcomes, with uniform Brier scores of 0.18. The 14-day mortality rates had AUCs of 0.867 and 0.87, and corresponding Brier scores of 0.21 and 0.22, respectively.

Conclusion: Both the CRASH and IMPACT algorithms offer reliable prognostic estimations for patients suffering from craniocerebral injuries. However, compared to the CRASH model, the IMPACT model has superior predictive accuracy, albeit at the cost of increased computational intricacy.

Our previous studies have shown that early exercise intervention after stroke increases neural activity and synaptic plasticity and promotes the recovery of nerve fiber bundle integrity in the brain. However, the effect of exercise on the repair of myelin in the brain and the related mechanism are still unclear. In this study, we randomly divided the rats into three groups. Before and after 28 days of intervention, body weight, nerve function, the infarct size, white matter fiber bundle integrity, and nerve myelin structure and function were observed by measuring body weight, analysis of modified neurological severity score, CatWalk gait analysis, MRI, luxol fast blue staining, immunofluorescence, and transmission electron microscopy. Changes in the expression of proteins in the MEK/ERK pathway were assessed. The results showed that early exercise intervention resulted in neurological recovery, decreased the infarct volume and increased nerve fiber integrity, the myelin coverage area, myelin basic protein (MBP) fluorescence intensity expression, and myelin thickness. Furthermore, the expression level of MBP was significantly increased after early exercise intervention, while the expression levels of p-MEK1/2 and p-ERK1/2 were significantly reduced. In the cell study, MBP expression levels were significantly higher in the oxygen and glucose deprivation and administration group.In summary, early exercise intervention after stroke can promote myelin repair by inhibiting the MEK/ERK signaling pathway.

Background: Silibinin has been found to inhibit glioblastoma (GBM) progression. However, the underlying molecular mechanism by which Silibinin regulates GBM process remains unclear.

Methods: GBM cell proliferation, apoptosis, invasion, and stemness are assessed by cell counting kit-8 assay, EdU assay, flow cytometry, transwell assay, and sphere formation assay. Western blot is used to measure the protein expression levels of apoptosis-related markers, solute carrier family 1 member 5 (SLC1A5), and Yin Yang-1 (YY1). Glutamine consumption, glutamate production, and α-ketoglutarate production are detected to evaluate glutamine metabolism in cells. Also, SLC1A5 and YY1 mRNA levels are examined using quantitative real-time PCR. Chromatin immunoprecipitation assay and dual-luciferase reporter assay are used to detect the interaction between YY1 and SLC1A5. Mice xenograft models are constructed to explore Silibinin roles in vivo.

Results: Silibinin inhibits GBM cell proliferation, invasion, stemness, and glutamine metabolism, while promotes apoptosis. SLC1A5 is upregulated in GBM and its expression is decreased by Silibinin. SLC1A5 overexpression abolishes the anti-tumor effect of Silibinin in GBM cells. Transcription factor YY1 binds to SLC1A5 promoter region to induce SLC1A5 expression, and the inhibition effect of YY1 knockdown on GBM cell growth, invasion, stemness, and glutamine metabolism can be reversed by SLC1A5 overexpression. In addition, Silibinin reduces GBM tumor growth by regulating YY1/SLC1A5 pathway.

Conclusion: Silibinin plays an anti-tumor role in GBM process, which may be achieved via inhibiting YY1/SLC1A5 pathway.

Objective: Heterozygous mutations within the voltage-gated sodium channel α subunit (SCN1A) are responsible for the majority of cases of Dravet syndrome (DS), a severe developmental and epileptic encephalopathy. Development of novel therapeutic approaches is mandatory in order to directly target the molecular consequences of the genetic defect. The aim of the present study was to investigate whether cis-acting long non-coding RNAs (lncRNAs) of SCN1A are expressed in brain specimens of children and adolescent with epilepsy as these molecules comprise possible targets for precision-based therapy approaches.

Methods: We investigated SCN1A mRNA expression and expression of two SCN1A related antisense RNAs in brain tissues in different age groups of pediatric non-Dravet patients who underwent surgery for drug resistant epilepsy. The effect of different antisense oligonucleotides (ASOs) directed against SCN1A specific antisense RNAs on SCN1A expression was tested.

Results: The SCN1A related antisense RNAs SCN1A-dsAS (downstream antisense, RefSeq identifier: NR_110598) and SCN1A-usAS (upstream AS, SCN1A-AS, RefSeq identifier: NR_110260) were widely expressed in the brain of pediatric patients. Expression patterns revealed a negative correlation of SCN1A-dsAS and a positive correlation of lncRNA SCN1A-usAS with SCN1A mRNA expression. Transfection of SK-N-AS cells with an ASO targeted against SCN1A-dsAS was associated with a significant enhancement of SCN1A mRNA expression and reduction in SCN1A-dsAS transcripts.

Conclusion: These findings support the role of SCN1A-dsAS in the suppression of SCN1A mRNA generation. Considering the haploinsufficiency in genetic SCN1A related DS, SCN1A-dsAS is an interesting target candidate for the development of ASOs (AntagoNATs) based precision medicine therapeutic approaches aiming to enhance SCN1A expression in DS.

Attention deficit hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders diagnosed in childhood. Two common features of ADHD are impaired behavioural inhibition and sustained attention. The Go/No-Go experimental paradigm with concurrent functional magnetic resonance imaging (fMRI) scanning has previously revealed important neurobiological correlates of ADHD such as the supplementary motor area and the prefrontal cortex. The coordinate-based meta-analysis combined with quantitative techniques, such as activation likelihood estimate (ALE) generation, provides an unbiased and objective method of summarising these data to understand the brain network architecture and connectivity in ADHD children. Go/No-Go task-based fMRI studies involving children and adolescent subjects were selected. Coordinates indicating foci of activation were collected to generate ALEs using threshold values (voxel-level: p < 0.001; cluster-level: p < 0.05). ALEs were matched to one of seven canonical brain networks based on the cortical parcellation scheme derived from the Human Connectome Project. Fourteen studies involving 457 children met the eligibility criteria. No significant convergence of Go/No-Go related brain activation was found for ADHD groups. Three significant ALE clusters were detected for brain activation relating to controls or ADHD < controls. Significant clusters were related to specific areas of the default mode network (DMN). Network-based analysis revealed less extensive DMN, dorsal attention network, and limbic network activation in ADHD children compared to controls. The presence of significant ALE clusters may be due to reduced homogeneity in the selected sample demographic and experimental paradigm. Further investigations regarding hemispheric asymmetry in ADHD subjects would be beneficial.

David M. Holtzman and his team at the University of Washington School of Medicine have made breakthroughs in their research on neurodegenerative diseases. They discovered that the infiltration of T cells into the brain, instigated by activated microglia, is a critical factor in the progression of tauopathy. The groundbreaking findings were published in Nature on March 8, 2023. This research delineates a pivotal immune hub linked to tauopathy and neurodegeneration; a complex interplay involving activated microglia and T cell responses. This discovery could potentially become a target for developing therapeutic interventions for Alzheimer's disease and primary neurodegeneration.

Brain vascular inflammation is characterized by endothelial activation and immune cell recruitment to the blood vessel wall, potentially causing a breach in the blood - brain barrier, brain parenchyma inflammation, and a decline of cognitive function. The clinical-stage small molecule, apabetalone, reduces circulating vascular endothelial inflammation markers and improves cognitive scores in elderly patients by targeting epigenetic regulators of gene transcription, bromodomain and extraterminal proteins. However, the effect of apabetalone on cytokine-activated brain vascular endothelial cells (BMVECs) is unknown. Here, we show that apabetalone treatment of BMVECs reduces hallmarks of in vitro endothelial activation, including monocyte chemoattractant protein-1 (MCP-1) and RANTES chemokine secretion, cell surface expression of endothelial cell adhesion molecule VCAM-1, as well as endothelial capture of THP-1 monocytes in static and shear stress conditions. Apabetalone pretreatment of THP-1 downregulates cell surface expression of chemokine receptors CCR1, CCR2, and CCR5, and of the VCAM-1 cognate receptor, integrin α4. Consequently, apabetalone reduces THP-1 chemoattraction towards soluble CCR ligands MCP-1 and RANTES, and THP-1 adhesion to activated BMVECs. In a mouse model of brain inflammation, apabetalone counters lipopolysaccharide-induced transcription of endothelial and myeloid cell markers, consistent with decreased neuroendothelial inflammation. In conclusion, apabetalone decreases proinflammatory activation of brain endothelial cells and monocytes in vitro and in the mouse brain during systemic inflammation.