LncRNA nuclear-enriched abundant transcript 1 aggravates cerebral ischemia/reperfusion injury through activating early growth response-1/RNA binding motif protein 25 axis.

Ischemic stroke is a major global health issue. Ischemia and subsequent reperfusion results in stroke-related brain injury. Previous studies have demonstrated that nuclear-enriched abundant transcript 1 (NEATa and early growth response 1 (EGR1) are involved in ischemia reperfusion (IR) injury). In this study, we aimed to explore the roles of NEAT1/EGR1 axis as well as its downstream effector RNA binding motif protein 25 (RBM25) in cerebral IR injury. Oxygen-glucose deprivation/reperfusion (OGD/R) and middle cerebral artery occlusion (MCAO) were used to establish in vitro and in vivo models of cerebral IR injury, respectively. According to our data, NEAT1, EGR1, and RBM25 levels were elevated in OGD/R-exposed SK-N-SH and SH-SY5Y cells and cerebral cortex of MCAO mice. NEAT1, EGR1, or RBM25 knockdown effectively reduced infarct volumes and apoptosis, and improved neurological function. Mechanistically, NEAT1 directly interacted with EGR1, which restrained WW domain containing E3 ubiquitin protein ligase 1 (WWP1)-mediated ubiquitination of EGR1 and subsequently caused EGR1 accumulation. EGR1 bound to RBM25 promoter and transcriptionally activated RBM25. Rescue experiments indicated that RBM25 overexpression abolished the therapeutic effects of NEAT1 knockdown. In conclusion, this work identified a novel NEAT1/EGR1/RBM25 axis in potentiating brain injury after IR insults, suggesting a potential therapeutic target for ischemic stroke.

Investigation on Potential Biomarkers and Immune-Related Mechanisms of Ischemic Stroke.

BACKGROUND: This study aimed to reveal the detailed immune-related mechanisms underlying ischemic stroke (IS) and identify new immune-associated biomarkers for clinical management. METHODS: Differentially expressed genes (DEGs) between IS samples and normal controls were identified using the GSE16561 dataset. The feature genes of the immune cells were investigated using the GSE72642 dataset. Weighted correlation network analysis (WGCNA) was performed to reveal module genes, followed by an investigation of common DEGs and a functional enrichment analysis. Potential biomarkers were identified based on hub genes in protein-protein interaction networks and WGCNA. Finally, GSE158312 was used for biomarker verification. RESULTS: In total, 1230 DEGs were identified between the IS samples and normal controls. Seven clinically significant modules were identified using WGCNA. The yellow module genes were positively correlated with polymorphonuclear cells (PMNC), whereas the brown module genes were positively correlated with CD4+ T cells. Eight genes were selected as hub genes. These genes are mainly involved in functions such as the innate immune response. Upregulated TLR2 and ARG1 levels were significantly different between the two groups in the verification dataset. CONCLUSIONS: Our findings suggest ARG1 and TLR2 as novel biomarkers for IS. Upregulated TLR2 might play a role in IS development by participating in the innate immune response function.

Molecular differences in Alzheimer's disease between male and female patients determined by integrative network analysis.

Alzheimer's disease (AD) is a complex neurodegenerative disease and the most common cause of dementia among the elderly. There has been increasing recognition of sex differences in AD prevalence, clinical manifestation, disease course and prognosis. However, there have been few studies on the molecular mechanism underlying these differences. To address this issue, we carried out global gene expression and integrative network analyses based on expression profiles (GSE84422) across 17 cortical regions of 125 individuals with AD. There were few genes that were differentially expressed across the 17 regions between the two sexes, with only four (encoding glutamate metabotropic receptor 2, oestrogen-related receptor beta, kinesin family member 26B, and aspartoacylase) that were differentially expressed in three regions. A pan-cortical brain region co-expression network analysis identified pathways and genes (eg, glycogen synthase kinase 3ß) that were significantly associated with clinical characteristics of AD (such as neurofibrillary score) in males only. Similarity analyses between region-specific networks indicated that male patients exhibited greater variability, especially in the superior parietal lobule, dorsolateral prefrontal cortex and occipital visual cortex. A network module analysis revealed an association between clinical traits and crosstalk of sex-specific modules. An examination of temporal and spatial patterns of sex differences in AD showed that molecular networks were more conserved in females than in males in different cortical regions and at different AD stages. These findings provide insight into critical molecular pathways governing sex differences in AD pathology.

Olfactory Impairment and Hippocampal Volume in a Chinese MCI Clinical Sample.

PURPOSE: The aim of this study was to evaluate the relationship between olfactory function and hippocampal volume in patients with mild cognitive impairment (MCI). METHODS: We enrolled a total of 31 MCI patients and 9 normal control subjects. All participants underwent 3.0 T-magnetic resonance imaging scanning. The scan results were processed using GE ADW4.6 processing software and V0xar 3D workstation to acquire the hippocampal volume. The University of Pennsylvania Smell Identification Test (UPSIT) was used to evaluate the olfactory function of MCI patients. The correlations of UPSIT score with hippocampal volume and hippocampal head volume were evaluated by Pearson correlation coefficient analysis. RESULTS: MCI patients had significantly smaller left (2.78±0.50 vs. 3.19±0.31 cm(3)) and right (2.97±0.42 vs. 3.31±0.25 cm(3)) hippocampal volumes compared with normal controls (P<0.05). In addition, patients with olfactory dysfunction had smaller volumes of the hippocampus (left hippocampal volume, 2.57±0.39 vs. 3.23±0.40 cm(3); right hippocampal volume, 2.86±0.43 vs. 3.22±0.30 cm(3)) and hippocampal head (left hippocampal head volume, 1.18±0.16 vs. 1.53±0.25 cm(3); right hippocampal head volume, 1.25±0.22 vs. 1.54±0.22 cm(3)) compared with those with normal olfactory function (P<0.05). No significant difference in the hippocampal body volume and hippocampal tail volume was found between MCI patients with olfactory loss and those with normal olfactory function. The UPSIT score was significantly positively correlated with left hippocampal volume (r=0.55, P<0.05), right hippocampal volume (r=0.42, P<0.05), left hippocampal head volume (r=0.53, P<0.05), and right hippocampal head volume (r=0.45, P<0.05). CONCLUSIONS: Olfactory function correlates well with hippocampal volume among patients with MCI.

Effect of focal mild hypothermia on expression of MMP-9, TIMP-1, Tau-1 and ß-APP in rats with cerebral ischaemia/reperfusion injury.

PRIMARY OBJECTIVE: Following stroke, hypothermia is reported to reduce both cellular and extracellular damage. This study aimed to examine the effects of focal mild hypothermia on proteins associated with both extracellular (matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of MMP-9 (TIMP-1)) and cellular damage (Tau-1 and ß-amyloid precursor protein (ß-APP)) to characterize the protective effects of hypothermia. METHODS AND PROCEDURES: Male Wistar rats received ischaemic damage using a transient, focal ischaemia/reperfusion model. Afterwards, one group (HT) received 6 hours of focal mild hypothermia (33 °C) applied to the head, while another remained at normal temperature (NT). The brains were collected at 6, 12, 24, 48 and 72 hours after hypothermia to measure infarct volume ratio and to detect cells immunopositive for MMP-9, TIMP-1, Tau-1 and ß-APP, while neurological deficits were examined separately after 2 weeks. MAIN OUTCOMES AND RESULTS: Focal mild hypothermia had no effect on infarct volume ratio but expression of MMP-9, TIMP-1 Tau-1 and ß-APP was decreased. Furthermore, neurological function in the HT group was better than in the NT group. CONCLUSIONS: Focal mild hypothermia has protective effects on cerebral ischaemia-reperfusion injury characterized by decreased expression of MMP-9, TIMP-1, Tau-1 and ß-APP, along with improvement of neurological function despite no changes in infarct volume.

An interventional study of baicalin on neuronal pentraxin-1, neuronal pentraxin-2, and C-reactive protein in Alzheimer's disease rat model.

Background: Baicalin has been shown to promote spatial learning and neural regeneration, which might increase the differentiation of neural stem cells in Alzheimer's disease (AD) rat models. We aimed to study the role of baicalin on neuronal pentraxin-1 (NPTX-1), neuronal pentraxin-2 (NPTX-2), and C-reactive protein (CRP) in AD model rats. Methods: The 30 male Sprague Dawley rats were divided into three groups: the control group, the AD model group, and the AD + baicalin group. Then, the Morris water maze was used to verify the effect of baicalin on the memory and spatial learning of rats. Immunohistochemistry and immunofluorescence were used to observe the expression of NPTX-1, NPTX-2, and CRP in brain tissue. Results: Compared with the AD model group, the AD rats treated with baicalin spent significantly less time finding escape latencies (P = 0.008) and had longer cross-platform times in the target quadrant (P = 0.015). In addition, the AD + baicalin group had significantly higher numbers of hippocampal neurons compared with the AD model group (P < 0.05). Baicalin also obviously decreased the apoptosis of neurons. Moreover, compared with the AD model group, the NPTX-1 and CRP expression in the AD + baicalin group was significantly reduced (P = 0.000) while the expression of NPTX-2 in the brain tissue of AD rats was significantly increased (P = 0.000). Conclusions: Baicalin can play a therapeutic role by downregulating NPTX-1, upregulating NPTX-2, and downregulating CPR in AD model rats.

Protective effect of edaravone against PrP106-126-induced PC12 cell death.

The prion protein peptide PrP106-126 induces cell apoptosis through mechanisms involving production of intracellular reactive oxygen species. The present study investigated the effects of edaravone, a potent free radical scavenger in clinical use, on cell cytotoxicity induced by PrP106-126. Results showed that PrP106-126 decreased PC12 cell viability in a dose- and time-dependent manner. Edaravone significantly antagonized the cytotoxic effects of PrP106-126. Mechanistically, PrP106-126 decreased PC 12 intracellular glutathione (GSH) concentrations, decreased superoxide dismutase (SOD) enzyme activity, increased concentrations of the oxidation end product malondialdehyde (MDA), depolarized the mitochondrial membrane, and increased caspase-3 activity. Edaravone alone did not affect GSH, SOD, or MDA but did effectively reverse all of the intracellular prooxidant effects induced by PrP106-126 and inhibit induced apoptosis in PC12 cells. In conclusion, edaravone may be a viable candidate for the treatment of oxidative stress-induced neurodegenerative disease.

[Influences of bFGF and EGF on the proliferation and differentiation of endogenous neural stem cells after cerebral infarction in human].

OBJECTIVE: To investigate the relationship of basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) and proliferation of endogenous neural stem cells (NSCs) after human cerebral infarction. METHODS: Paraffin-embedded brain tissues of 22 human fatal cases of CI from the brain tissues around subventricular zone and subgranular layer zone were stained with HE and immunohistochemistry stain. The endogenous neural stem cells were marked by nestin. The expression changes of EGF, bFGF and nestin in the perihematomal tissues were analysed with the SPSS 13.0 system. RESULTS: (1) Compared with the controls, the number of nestin-positive cells increased at 24 - 72 h (14 +/- 6)/HP in the ipsilateral SVZ and began to rise at 4.5 - 10 h (11 +/- 5)/HP in the ipsilateral SGZ, reached maximum at 120 - 144 h ((38 +/- 7)/HP in the SVZ, (54 +/- 17)/HP in the SGZ, and decreased markedly at 216 - 336 h, but it was still elevated compared with the controls (P < 0.05). (2) The number of bFGF-positive cells increased at 4.5 - 10 h (8.1 +/- 2.9)/HP in the SVZ, (19.0 +/- 8.2)/HP in the SGZ, reached maximum at 24 - 70 h (15.6 +/- 3.5)/HP in the SVZ, (32.0 +/- 5.7)/HP in the SGZ and decreased at 72 - 96 h, but it was still elevated compared with the controls (P < 0.05). (3) The number of EGF-positive cells increased at 4.5 - 10 h (4.3 +/- 1.6)/HP in the SVZ, (7.0 +/- 3.7)/HP in the SGZ, reached maximum at 120 - 144 h (27.0 +/- 1.4)/HP in the SVZ, (51.5 +/- 4.9)/HP in the SGZ and decreased at 216 - 336 h, but it was still elevated compared with the controls (P < 0.05). CONCLUSIONS: Perhaps the increased expression of EGF and bFGF after CI was a reaction of endogenous reparation and it correlated with the proliferation and endogenous of neural stem cells in human.

[Expressions of heme oxygenase-1 and apoptosis-modulating proteins in peri-hematoma cortex after intracerebral hemorrhage in human being].

OBJECTIVE: To observe the expression of heme oxygenase-1 (HO-1) and Bcl-2, an apoptosis-modulating protein, in the neurons surrounding the hematoma in human being. METHODS: Specimens of cerebral cortex tissue 1 - 3 cm around the hemorrhagic focus with the size of 2.0 cm x 1.5 cm x 0.3 cm were collected during autopsy from 39 patients, 17 males and 22 females, aged 62.8 (36 - 84), who died from intracerebral hemorrhage 2 - 10 h, 17 - 30 h, 36 - 96 h, 120 - 216 h, or 240 - 408 h before. Specimens of brain tissue of the same size at the opposite side were collected as controls. Immunohistochemistry was used to examine the expression of HO-1 and Bcl-2 protein. RESULTS: (1) Expression of HO-1 could be detected in the specimens of the 2 h group, increased in the specimens of the 2 - 10 h group [(5.1 +/- 2.0)/HP], reached the peak in the 17 - 30 h group [(11.3 +/- 0.9)/HP], then began to decrease in the specimens of the 240 - 408 h group [(6.4 +/- 0.6)/HP] (F = 42.80, P < 0.001). The HO-1 expression of the control group remained negative at any time-point. (2) Expression of Bcl-2 could be detected in the specimens of the 2 - 10 h group [(4.2 +/- 1.7)/HP], was increased in the 17 - 30 h group [(6.6 +/- 0.5)/HP], reached the peak in the 36 approximately 96 h group [(8.9 +/- 1.1)/HP], then began to decrease, and was (4.7 +/- 0.6)/HP in the 240 approximately 408 h group (F = 29.59, P < 0.001). The Bcl-2 expression remained negative at any time point in the control group. (3) The expressions of HO-1 was positively correlated with the expression of Bcl-2 (r = 0.66, P < 0.001). CONCLUSIONS: Over-expression of HO-1 and Bcl-2 in the neurons provide a potential protection or destruction mechanism after intracerebral hemorrhage in human.

[Effect of local mild hypothermia on expression of aquaporin-4 following intracerebral hemorrhage in rats].

OBJECTIVE: To examined the effect of local mild hypothermia on the expression of aquaporin-4 (AQP-4) following intracerebral hemorrhage (ICH) in rats and clarified the mechanism of hypothermia on brain edema formation following ICH. METHODS: Two hundreds and forty male Wistar rats were randomly divided into two groups: the intracerebral hemorrhage (ICH) group, in which autologous arterial blood were stereotaxically injected into right caudate nucleus; the local mild hypothermia (ICH + H) group, in which the rats were given 4 h local mild hypothermia after the injection of blood. Each group was divided into 6 subgroups: control, 6 h, 24 h, 72 h, 5 d and 7 d after operation; Brain water content was determined by dry-wet weight method and the permeability of BBB was measured by Evans-Blue extravasation. RT-PCR and Western blot were respectively used to evaluate AQP-4 mRNA and protein expression. RESULTS: In ICH group, compared with control, ICH significantly increased BWC, the permeability of BBB and the expression of AQP-4 mRNA, all began at 6 h and peaked at 72 h (P < 0.01), the increased protein expression of AQP-4 began at 24 h and also peaked at 72 h (P < 0.01). AQP-4 expression positively correlated, both at the mRNA and the protein level, with the permeability of BBB (r = 0.78 and r = 0.76 respectively). In ICH + H group, compared with ICH group, the elevation of BWC, BBB permeability and AQP-4 protein expression were strongly attenuated at all time point by hypothermia treatment (P < 0.01), while AQP-4 mRNA levels demonstrated a modest attenuation from 48 h. At 72 h, AQP-4 mRNA optical density (A) decreased from 1.25 +/- 0.03 (ICH group) to 1.04 +/- 0.02 (P < 0.01), AQP-4 protein expression (A) decreased from 0.77 +/- 0.08 (ICH group) to 0.25 +/- 0.04 (P < 0.01). CONCLUSIONS: This study indicates that BBB breakdown can increase the expression of AQP-4; local mild hypothermia can significantly reduce brain edema formation after ICH by suppressing the elevation of AQP-4 protein expression; Inhibition of BBB breakdown and the elevation of AQP-4 protein expression with local mild hypothermia appear to contribute to brain protection in this model.

IL-6-174 G/C and -572 C/G polymorphisms and risk of Alzheimer's disease.

Associations between interleukin 6 (IL-6) polymorphisms and Alzheimer's disease (AD) remain controversial and ambiguous. The aim of this meta-analysis is to explore more precise estimations for the relationship between IL-6-174 G/C and -572 C/G polymorphisms and risk for AD. Electronic searches for all publications in databases PubMed and EMBASE were conducted on the associations between IL-6 polymorphisms and risk for AD until January 2012. Odds ratio (OR) and 95% confidence intervals (CIs) were calculated using fixed and random effects models. Twenty-seven studies were included with a total of 19,135 individuals, involving 6,632 AD patients and 12,503 controls. For IL-6-174 G/C polymorphism, the combined results showed significant differences in recessive model (CC vs. CG+GG: OR = 0.65, 95%CI = 0.52-0.82). As regards IL-6-572 C/G polymorphism, significant associations were shown in dominant model (CG+GG vs. CC: OR= 0.73, 95% CI = 0.62-0.86) and in additive model (GG vs. CC, OR= 0.66, 95% CI = 0.46-0.96). In conclusion, genotype CC of IL-6-174 G/C and genotype GG plus GC of IL-6-572 C/G could decrease the risk of AD.

Increased levels of IL-23 and osteopontin in serum and cerebrospinal fluid of multiple sclerosis patients.

Osteopontin (OPN) and interleukin-23 (IL-23) are pro-inflammatory cytokines proposed to play central roles to the development of multiple sclerosis (MS). The aim of this study was to evaluate levels of OPN, IL-23 and other inflammatory cytokines and investigate their relationships in serum and cerebrospinal fluid (CSF) in patients with MS. Fifty one MS patients and 48 patients with non-inflammatory neurological diseases (NIND) were recruited from clinic. The levels of OPN, IL-23, IL-17, IL-6, and tumor necrosis factor-alpha (TNF-alpha) in serum and CSF were determined in each participant. Compared with NIND group, MS patients had significantly elevated levels of OPN, IL-23, IL-17 and TNF-alpha in CSF, and elevated levels of IL-23, IL-17 and TNF-alpha in serum (All P<0.001). In MS patients, OPN and IL-23 were positively correlated with IL-17 (r=0.302, P=0.019; r=0.417, P=0.001, respectively); and IL-23 was positively correlated with EDSS (r=0.329, P=0.019). Both OPN and IL-23 may play pivotal role in development of MS and might be specific markers and therapeutic targets for MS.

Expression of nestin and glial-derived neurotrophic factor in human endogenous neural stem cells following ischemia.

OBJECTIVES: We investigated the relationship between glial cell line-derived neurotrophic factor (GDNF), nestin, and the activation of endogenous neural stem cells (NSCs) following cerebral infarction in humans. METHODS: Post-mortem brain specimens from patients who died following cerebral infarction were examined. RESULTS: Compared with the controls, the number of nestin-positive cells was increased at 4·5-10 hours in the subgranular zone of the hippocampus dentate gyrus and at 24-72 hours in the subventricular zone, reaching maximum levels at 120-144 hours. Cell numbers decreased at 216-326 hours, but remained elevated compared with controls. Similar results were found when examining the expression of GDNF following ischemia. Furthermore, the expression of nestin and GDNF showed a statistically significant positive correlation over time. CONCLUSIONS: Our results indicate that, as in other mammals, proliferation of endogenous neural stem cells in the subventricular zone and subgranular zone of the hippocampus dentate gyrus of humans is activated by cerebral infarction and may be related to increases in GDNF expression.

Ischemia induces endoplasmic reticulum stress and cell apoptosis in human brain.

In animal models, endoplasmic reticulum (ER) stress and apoptosis take place around cerebral infarction areas during ischemia, which presumably protect tissues from necroses-induced injury as well as promote cells toward death. We examined whether these pathological changes, especially temporal occurrence, were present in patients who suffered from cerebral ischemia. The studies by immunohistochemistry show that ER chaperone glucose-regulated protein (GRP78) and caspase-9 elevate around infarction areas. The experiments by terminal deoxynucleotidy transferase-mediated 2'-deoxyuridine 5'-triphosphate-biotin nick-end labeling (TUNEL) illustrate that TUNEL-positive cells are higher around infarction tissues than controls. Moreover, GRP78, caspase-9 and TUNEL cells emerge one after another during ischemia. In conclusion, ER stress, apoptosis initiation and DNA fragment develop sequentially in ischemic human brain. ER stress during excessive ischemia stimulates apoptotic cell death beyond activating a defense for nerve cells being away from injury.

[Fingerprinting of Fuzhisan by high-performance liquid chromatography with ultraviolet and evaporative light scattering detector].

OBJECTIVE: To establish a method for fingerprinting of Fuzhisan (FZS, a traditional Chinese medicinal preparation) using high-performance liquid chromatography with ultraviolet and evaporative light scattering detector (HPLC-UV/ELSD) to allow simultaneous determination of 5 major constituents in the preparation. METHODS: HPLC-UV/ELSD analysis was performed on water AlltechC18 column (5 microm, 4.6 mm x 250 mm) with a mixture of acetonitrile (A) and 0.1% acetice acid water (B) as the mobile phase. The solvent A gradient for elution was 0, 12%; 25, 20%; 30, 20%; 75, 30%; 105, 40%; 120, 80%; 130, 12%, with the flow rate of 1.0 ml/min; and the column temperature at 30 degrees . The detective wavelength was 335 nm, drift tube temperature was 80 degrees , pressure of nebulizer gas was 25 psi. The similarities between the HPLC-UV/ELSD fingerprints of the 12 extracts were calculated using similarity evaluation software. RESULTS: The fingerprint of FZS was established and the 5 major constituents were identified. The complementarity between the fingerprints of UV and ELSD was analyzed, showing good correlation between 12 batches of FZS. CONCLUSION: The method for fingerprinting can simultaneously characterize the main chemical constituents in FZS and allows stable, effective and comprehensive quality control and evaluation of FZS for a single sample.