The Relationship Between MMP17 Variants and Ischemic Stroke Risk in the Population from Shaanxi Province in China.

Background: Ischemic stroke (IS) was a multifactorial disease, which was the main cause of death and adult disability. Genetic factors cannot be ignored. Objective: The present study discussed the relationship between MMP17 variants and the susceptibility of IS. Methods: Based on the Agena MassARRAY platform, we genotyped single nucleotide polymorphisms (SNPs) on the MMP17 gene in 1345 participants (670 controls and 675 cases). We used logistic regression analysis to analyze the association of MMP17 SNPs with the risk of IS in the Chinese population, with odds ratio (OR) and 95% confidence intervals (CIs). False-positive report probability (FPRP) detected false positives on the significant results. Besides, we detected the SNP-SNP interaction to predict IS risk by multi-factor dimensionality reduction (MDR) analysis. Results: In the total analysis, MMP17 rs7975920 conferred an increased susceptibility to IS. After a stratified analysis by age and gender, the significant association between rs7975920 and IS risk was displayed in the subjects aged >55 years old and females. After stratified analysis by smoking and drinking, MMP17 rs6598163 was related to the risk of IS in smokers and rs7975920 was associated with the risk of IS in smokers and was in correlation with IS risk in drinkers. Conclusion: In short, we first observed that MMP17 rs7975920 and rs6598163 were related to the risk of IS. The above results provided a theoretical basis for the elaboration of the role of MMP17 in IS in the Chinese population.

Endovascular recanalization in patients with severely disabling non-acute ischemic stroke.

BACKGROUND: It is unclear whether patients with severely disabling ischemic stroke (SDIS-that is, modified Rankin scale (mRS) scores of 3-5) benefit from non-acute endovascular recanalization (ER). OBJECTIVE: To determine the effect of non-acute ER or medical treatment in severely disabled patients with non-acute ischemic stroke (mRS scores of 3-5). METHODS: Between January 2018 and August 2021, non-acute patients with SDIS and large vessel occlusion were collected from two regional stroke centers. Patients who met the inclusion and exclusion criteria were assigned to two groups based on whether they underwent ER (ER group) or not (medical group). The primary functional outcome was the mRS score at 90 days. The primary safety outcomes were the recurrence of stroke and mortality. RESULTS: Of the 325 patients with hypoperfusion cerebral infarction caused by large vessel occlusion, 63 met the inclusion criteria (32 patients in the ER group, 31 patients in the medical group). A favorable outcome (mRS score ≤2) occurred more often in the ER group than in the medical group (59.4% vs 22.6%, respectively; OR=0.12, 95% CI 0.02 to 0.58; P<0.01). There were no significant differences in new-onset ischemic stroke (6.3% vs 3.2%, respectively; P=1.000), symptomatic intracerebral hemorrhage (12.5% vs 0%, respectively; P=0.113), or mortality within 90 days (6.3% vs 6.5%, respectively; P=1.000) between the two groups. Preoperative mRS scores (OR=7.34, 95% CI 1.56 to 34.5; P=0.02) and ER (OR=0.12, 95% CI 0.02 to 0.58; P<0.01) were significantly associated with outcome. CONCLUSION: Our data suggest that patients with SDIS (mRS score 3-5) with smaller infarct cores and better collateral circulation can benefit from non-acute ER, with no additional perioperative complications or mortality.

The cytoprotective role of omentin against oxidative stress-induced PC12 apoptosis.

Oxidative stress has been proven to play a critical role in the pathogenesis of neuronal injury. As a novel adipocytokine, omentin is produced by visceral adipose with insulin sensitizing effects and has been revealed to possess anti-inflammatory effects. However, the possible effect of omentin on oxidative stress remains unknown. The present study aimed to detect the potential protective effect of omentin against hydrogen peroxide (H2O2)-induced cytotoxicity of PC12 cells. The results showed that no cytotoxic effect was shown in PC12 cells co-cultured with omentin alone at a concentration of 50-1000 ng/mL. The CCK8 and TUNEL assays suggested that omentin could remarkably attenuate apoptosis induced by 100 µM H2O2. The PCR and western blotting showed that the expression levels of Bax was significantly inhibited by omentin via the upregulation of miR-128-3p at its 3'-UTR. Taken together, these results indicated that omentin protects PC12 cells against H2O2-induced apoptosis, and further studies need to be conducted before utilization in the clinic for the treatment of neurodegenerative diseases.

MicroRNA-769-5p Promotes The Growth Of Glioma Cells By Targeting Lysine Methyltransferase 2A.

BACKGROUND: Accumulating evidence supports the involvement of microRNAs (miRNAs) in the progression of human cancers including glioma. Recently, miR-769-5p has been reported to play a tumor suppressive role in colorectal cancer and lung cancer, whereas it exerts an oncogenic role in melanoma. However, the role of miR-769-5p and its related mechanism are poorly elucidated. METHODS: The levels of miR-769-5p in glioma tissues and adjacent non-tumor tissues were detected by qRT-PCR. In addition, the effects of miR-769-5p on cell proliferation and apoptosis were evaluated by CCK-8, EdU, colony formation and flow cytometric assays, respectively. Meanwhile, the dual-luciferase reporter assay was used to investigate the interaction of miR-769-5p and lysine methyltransferase 2A (KMT2A) in glioma. RESULTS: We found that miR-769-5p expression was strongly upregulated in glioma tissues and cell lines. Glioma tissues with high World Health Organization (WHO) grades had obvious higher levels of miR-769-5p compared to samples with low WHO grades. Interestingly, glioma patients highly expressing miR-769-5p showed prominent poorer survivals. Knockdown of miR-769-5p significantly suppressed cell proliferation and resulted in apoptosis in glioma cells. Additionally, miR-769-5p silencing restrained in vivo growth of glioma cells in mice. Interestingly, KMT2A was identified to be a direct target of miR-769-5p in glioma cells. The expression of KMT2A mRNA was downregulated in glioma tissues and inversely correlated with miR-769-5p level. KMT2A overexpression inhibited cell proliferation and induced the apoptosis of A172 cells. Moreover, siRNA-mediated KMT2A silencing could partially abolish miR-769-5p knockdown-induced suppressive effects on A172 cells. CONCLUSION: In summary, our findings suggest that targeting miR-769-5p/KMT2A axis may be a promising therapeutic target for glioma treatment.

Suppression of SIRT6 by miR-33a facilitates tumor growth of glioma through apoptosis and oxidative stress resistance.

microRNA-33a (miR-33a) belongs to the miR-33 family that is implicated in the progression of various types of cancers. Aberrant expression of miR-33a has been detected in several human cancers, and has been shown to regulate the migration and invasion as well as proliferation and apoptosis of tumor cells. However, the clinical significance and precise mechanisms underlying the dysfunction of miR-33a in glioma have not been well investigated in previous studies. In this study, overexpression of miR-33a was observed in clinical glioma specimens and cell lines. Clinicopathological detection revealed that miR-33a highly expressing patients showed large tumor sized and advanced World Health Organization (WHO) grade as well as reduced overall survival. Furthermore, the results of in vitro experiments confirmed that loss of miR-33a resulted in reduced proliferation and enhanced apoptosis in U251 cells, while miR-33a restoration showed opposite effects in U87 cells. Further studies indicated that miR-33a knockdown restrained tumor growth of glioma in vivo. miR-33a negatively regulated the expression of sirtuin 6 (SIRT6) at both mRNA and protein levels via targeting the 3'UTR of SIRT6 mRNA. SIRT6 was underexpressed and inversely correlated with miR-33a expression in the glioma tissues. Mechanistically, SIRT6 overexpression increased the levels of lactate dehydrogenase (LDH) and reactive oxygen species (ROS) while it reduced cell survival under H2O2 treatment. In addition, SIRT6 restoration led to apoptosis with alterative expression of Bax, Bcl-2, cleaved caspase-8, and inhibition of Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway in glioma. Thus, our studies demonstrated that the deregulation of miR-33a may promote tumor development in human glioma by regulating the expression of its target gene, SIRT6.

Neuroglobin functions as a prognostic marker and promotes the tumor growth of glioma via suppressing apoptosis.

Neuroglobin (Ngb) has been reported to be upregulated by hypoxia and plays an anti-apoptotic function. Previous studies have reported that Ngb is expressed in human glioblastoma cells and up-regulated in hypoxic microregions of glioblastoma tumor xenografts. While, the clinical significance of Ngb and its function in human glioma keep unknown. Ngb expression was analyzed in 86 glioma tissues and 20 normal brain tissues. Results showed that Ngb was significantly overexpressed in glioma tissues compared to normal brain tissues. In addition, increased levels of Ngb also observed in glioma cell lines. Clinicopathological analysis verified that the positive expression of Ngb was associated with histological type and world health organization (WHO) grade of glioma. Moreover, Kaplan-Meier analysis found that Ngb overexpression led to a shorter survival. Multivariate Cox regression analysis demonstrated that Ngb expression was an independent prognostic marker. Further experiments illustrated that Ngb knockdown significantly inhibited proliferation and facilitated apoptosis in U251 cells. In vivo experiments further confirmed that Ngb silencing notably prohibited the tumor growth of glioma in nude mice. While, Ngb overexpression prominently promoted proliferation and suppressed apoptosis in U87 cells. Taken together, this work support the first evidence that Ngb can be potentially used as a promising biomarker and target for novel treatment of human glioma.

Anti-apoptotic and angiogenic effects of intelectin-1 in rat cerebral ischemia.

Ischemic stroke is an acute life-threatening disease, which causes neurological dysfunction. The formation of new blood vessels around the infarct is vital to the restoration of perfusion and healing of brain tissue. Studies have shown that intelectin-1 (omentin) promotes endothelial cell function and angiogenesis in response to ischemia and inhibits apoptosis in rats with unilateral hind limb surgery. In the present study, we investigated the neuroprotective role of intelectin-1 following focal cerebral ischemia. We specifically assessed the effect of increased expression of intelectin-1 in promoting angiogenesis and reducing apoptosis. The treatment was administered using a lentiviral vector, 7 days prior to surgery. The surgery was performed using the established middle cerebral artery occlusion (MCAO) model in rats, and the outcome was evaluated 7 days after injury. Our results demonstrated a significant reduction in brain infarction volume following LV-intelectin-1 treatment. Additionally, CD34 and capillary density were increased in the cerebral ischemic penumbra. Real-time PCR and Western blot revealed an increased expression of intelectin-1, and phosphorylation of eNOS and AKT with enhanced expression of bcl-2 in brain tissues. These data suggest that the successful delivery of LV-intelectin-1 ameliorated ischemic brain injury. It promoted endothelial cell function and revasc ularization, and inhibited apoptosis in response to ischemia by stimulating the Akt-eNOS signaling pathway.

Down-regulation of 14-3-3ß exerts anti-cancer effects through inducing ER stress in human glioma U87 cells: Involvement of CHOP-Wnt pathway.

We previously identified 14-3-3ß as a tumor-specific isoform of 14-3-3 protein in astrocytoma, but its functional role in glioma cells and underlying mechanisms are poorly understood. In the present study, we investigated the effects of 14-3-3ß inhibition in human glioma U87 cells using specific targeted small interfering RNA (siRNA). The results showed that 14-3-3ß is highly expressed in U87 cells but not in normal astrocyte SVGp12 cells. Knockdown of 14-3-3ß by Si-14-3-3ß transfection significantly decreased the cell viability but increased the LDH release in a time-dependent fashion in U87 cells, and these effects were accompanied with G0/G1 cell cycle arrest and apoptosis. In addition, 14-3-3ß knockdown induced ER stress in U87 cells, as evidenced by ER calcium release, increased expression of XBP1S mRNA and induction of ER related pro-apoptotic factors. Down-regulation of 14-3-3ß significantly decreased the nuclear localization of ß-catenin and inhibited Topflash activity, which was shown to be reversely correlated with CHOP. Furthermore, Si-CHOP and sFRP were used to inhibit CHOP and Wnt, respectively. The results showed that the anti-cancer effects of 14-3-3ß knockdown in U87 cells were mediated by increased expression of CHOP and followed inhibition of Wnt/ß-catenin pathway. In summary, the remarkable efficiency of 14-3-3ß knockdown to induce apoptotic cell death in U87 cells may find therapeutic application for the treatment of glioma patients.

Anti-inflammatory and antiapoptotic effects of mesenchymal stem cells transplantation in rat brain with cerebral ischemia.

BACKGROUND: Excessive inflammation and apoptosis contribute to the pathogenesis of ischemic brain damage. Nuclear factor-kappa B (NF-κB) is considered to be a key protein complex involved in this cascade of events. The aim of the present study was to clarify the protection mechanism of the mesenchymal stem cells (MSCs). METHODS: Lewis rats (N = 90) were randomly assigned to three groups: (1) the sham-operated group; (2) the saline group, in which the animals underwent rat transient middle cerebral artery occlusion (tMCAO, for 2 hours) and were treated with saline through the tail vein; and (3) the MSCs group, in which the animals underwent tMCAO (for 2 hours) and were infused with cultured human MSCs (4 × 10(6)/0.4 ml PBS) through the tail vein. At days 1 and 3 post-MSCs infusion, real-time PCR, and Western blot, immunohistochemical analyses were applied for tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and P-IKKß, p53, and B-cell lymphoma 2 (Bcl-2) expression levels. RESULTS: TNF-α, IL-1ß messenger RNA (mRNA) and P-IκB-α, P-IKKß, p53 protein expression levels were significantly increased in the saline group compared with the sham group. However, IκB-α and Bcl-2 protein expression levels were markedly decreased in the saline group. After injection of BrdU(+) MSCs, the expression levels of TNF-α, IL-1ß mRNA and P-IκB-α, P-IKKß, p53 protein were significantly decreased. Contrary to these findings, IκB-α, Bcl-2 protein expression levels were markedly increased. In addition, we found that infarct area was significantly reduced in MSCs group. CONCLUSIONS: These results suggest that MSCs' neuroprotection is attributable to its anti-inflammatory and antiapoptotic effect through inhibition of NF-κB.

Dynamin-related protein 1 inhibitors protect against ischemic toxicity through attenuating mitochondrial Ca2+ uptake from endoplasmic reticulum store in PC12 cells.

Intracellular calcium homeostasis disorder and mitochondrial dysfunction are involved in many acute and chronic brain diseases, including ischemic brain injury. An imbalance in mitochondrial fission and fusion is one of the most important structural abnormalities found in a large number of mitochondrial dysfunction related diseases. Here, we investigated the effects of mitochondrial division inhibitor A (mdivi A) and mdivi B, two small molecule inhibitors of mitochondrial fission protein dunamin-related protein 1 (Drp-1), in neuronal injury induced by oxygen-glucose deprivation (OGD) in PC12 cells. We found that mdivi A and mdivi B inhibited OGD-induced neuronal injury through attenuating apoptotic cell death. These two inhibitors also preserved mitochondrial function, as evidenced by reduced reactive oxygen species (ROS) generation and cytochrome c release, as well as prevented loss of mitochondrial membrane potential (MMP). Moreover, mdivi A and mdivi B significantly suppressed mitochondrial Ca(2+) uptake, but had no effect on cytoplasmic Ca(2+) after OGD injury. The results of calcium imaging and immunofluorescence staining showed that Drp-1 inhibitors attenuated endoplasmic reticulum (ER) Ca(2+) release and prevented ER morphological changes induced by OGD. These results demonstrate that Drp-1 inhibitors protect against ischemic neuronal injury through inhibiting mitochondrial Ca(2+) uptake from the ER store and attenuating mitochondrial dysfunction.

[A cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy pedigree: clinical pathology, neuroimaging and molecular genetics studies].

OBJECTIVE: To explore the clinical presentations, pathological features, imaging manifestation and genetic mutation of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). METHODS: A systematic study on the clinical manifestations, neuroimaging characteristics, pathology and molecular genetics was performed in the proband and 16 members of the family. An investigation on the hereditary pattern of the family tree of the proband was also conducted. RESULTS: The main clinical features including history of ischemic stroke attack, migraine, psychological disoders and dementia were noted. No risk factors of hypertension and arteriosclerosis were found. Pedigree maps of the index case were consistent with classical autosomal dominant inheritance. Subcortical multi-infarct lesions, leukoencephalopathy, O'Sullivan sign and "Herringbone pattern"shape sign were observed via cranial MRI analysis. By electron microscopy, skin biopsy indicated the characteristic deposition of granular osmiophilic material (GOM) on the basement of smooth muscle cells of arterioles in the proband. The mutation of C144Y in the fourth exon of notch 3 gene was revealed in three cases, including 1 patient with normal MRI. CONCLUSION: The pedigree is diagnosed with CADASIL. The main cause can be attributed to a mutation of C144Y in the fourth exon of Notch 3 gene. The pedigree has enriched Chinese database of CADASIL.

Protective effects and mechanism of puerarin on learning-memory disorder after global cerebral ischemia-reperfusion injury in rats.

OBJECTIVE: To observe the effect of puerarin on the learning-memory disorder after global cerebral ischemia-reperfusion injury in rats, and to explore its mechanism of action. METHODS: The global cerebral ischemia-reperfusion injury model was established using the modifified Pulsinelli four-vessel occlusion in Sprague-Dawley rats. Rats were intraperitoneally injected with puerarin (100 mg/kg) 1 h before ischemia and once every 6 h afterwards. The learning-memory ability was evaluated by the passive avoidance test. The dynamic changes of the cell counts of apoptosis and positive expression of Bcl-2 in the hippocampus CA1 region were determined by the TUNEL and immunohistochemical methods, respectively. RESULTS: (1) Compared with the reperfusion group, the step through latency (STL) in the passive avoidance test in the puerarin group was prolonged signifificantly (P<0.01). (2) The apoptotic neurons were injured most severely on the 3rd day in the hippocampal CA1 region after global ischemia and reperfusion. In the puerarin group, the number of apoptotic cells decreased at respective time points after ischemia-reperfusion (P<0.01). (3) The level of positive expression of Bcl-2 varied according to the duration of reperfusion and the peak level occurred on day 1 in the hippocampal CA1 region after global cerebral ischemia. Compared with the reperfusion group, the expression of Bcl-2 in the puerarin group was up-regulated at the respective time points after ischemia reperfusion (P<0.01), reaching the peak on day 1. CONCLUSIONS: Puerarin could improve the learning-memory ability after global cerebral ischemia and reperfusion in rats. The protective mechanism might be related to the effect of inhibiting or delaying the cell apoptosis through up-regulating the expression of Bcl-2 after ischemia and reperfusion.