Chronic Cerebral Hypoperfusion Promotes Amyloid-Beta Pathogenesis via Activating ß/γ-Secretases.

Chronic cerebral hypoperfusion (CCH) contributes to the Alzheimer's-like pathogenesis, but the relationship between CCH and the occurrence of Alzheimer's disease (AD) remains obscure. The aim is to elucidate the potential pathophysiological mechanism in the field of amyloid-beta (Aß) pathology induced by CCH. A rat model of CCH has been developed with permanent bilateral occlusion of common carotid arteries (BCCAO). The cognitive function of rats was tested by the Morris water maze. The levels of Aß (Aß40 and Aß42) and soluble amyloid precursor protein (sAPP: sAPPα and sAPPß) were determined by enzyme linked immunosorbent assay. The expression of beta-site amyloid precursor protein cleaving enzyme 1 (BACE1), presenilin1 (PS1), nicastrin (NCT), anterior pharynx-defective 1alpha (Aph-1α) and presenilin enhancer 2 (Pen-2), sAPPα and sAPPß were detected by Western blotting. Morris water maze test showed that CCH induced decline in learning and memory related to Aß levels in the hippocampus. The levels of sAPPα, ADAM10 and ADAM17 in the hippocampus of CCH rats were higher than the control ones (P < 0.05); the levels of sAPPß, BACE and BACE1 increased more than the control ones (P < 0.05). CCH intervention (1-week or 4-week) markedly increased the expression of PS1, Aph-1α and Pen-2 in the hippocampus of rats, but had no effect on NCT. CCH contributed to cognitive impairment and altered the amyloidogenic and non-amyloidogenic pathway of APP processing by boosting the activity of ß-secretase/γ-secretase and α-secretase respectively. The non-amyloidogenic pathway can't overcome the damage role of the amyloidogenic pathway in the process of chronic cerebral hypoperfusion which promotes amyloid-beta pathogenesis.

The incidence of cervical spondylosis decreases with aging in the elderly, and increases with aging in the young and adult population: a hospital-based clinical analysis.

BACKGROUND AND PURPOSE: Cervical spondylosis is well accepted as a common degenerative change in the cervical spine. Compelling evidence has shown that the incidence of cervical spondylosis increases with age. However, the relationship between age and the incidence of cervical spondylosis remains obscure. It is essential to note the relationship between age and the incidence of cervical spondylosis through more and more clinical data. METHODS: In the case-controlled study reported here, retrospective clinical analysis of 1,276 cases of cervical spondylosis has been conducted. We analyzed the general clinical data, the relationship between age and the incidence of cervical spondylosis, and the relationship between age-related risk factors and the incidence of cervical spondylosis. A chi-square test was used to analyze the associations between different variables. Statistical significance was defined as a P-value of less than 0.05. RESULTS: The imaging examination demonstrated the most prominent characteristic features of cervical spondylosis: bulge or herniation at C3-C4, C4-C5, and C5-C6. The incidence of cervical spondylosis increased with aging before age 50 years and decreased with aging after age 50 years, especially in the elderly after 60 years old. The occurrence rate of bulge or herniation at C3-C4, C4-C5, C5-C6, and C6-C7 increased with aging before age 50 years and decreased with aging after age 50 years, especially after 60 years. Moreover, the incidence of hyperosteogeny and spinal stenosis increased with aging before age 60 years and decreased with aging after age 60 years, although there was no obvious change in calcification. The age-related risk factors, such as hypertension, hyperlipidemia, diabetes, cerebral infarct, cardiovascular diseases, smoking, and drinking, have no relationship with the incidence of cervical spondylosis. CONCLUSION: A decreasing proportion of cervical spondylosis with aging occurs in the elderly, while the proportion of cervical spondylosis increases with aging in the young and the adults. This investigation implicates that aging is not only a contributor to the clinical performance of cervical spondylosis in the elderly, although the incidence of cervical spondylosis is proportional to the progress of age.

Preventive effect of dexamethasone gelatin sponge on the lumbosacral epidural adhesion.

OBJECTIVE: This study aims to explore the preventive effect of dexamethasone gelatin sponge on the lumbosacral epidural adhesion in the laminectomy. METHODS: A total of 36 Wista rats were divided into A, B, C and D groups randomly. Dexamethasone was not used in group A, Dexamethasone was used in group B, Dexamethasone was not used in group C but covered with gelatin sponge, dexamethasone gelatin sponge was used in group D. 3 rats in each group were sacrificed at 4, 8 and 12 weeks after operation respectively and the wound was opened to observe the dural scar formation and the dura adhesion. Immunohistochemical technique was used for histology observation. The expressions of VEGF and VEGFR2 in the epidural scar and surrounding tissues were detected with western blotting and immunohistochemical methods. RESULTS: According to the Rydell score standard, there were different degree of adhesion formation in A, B and C groups while there was no obvious adhesion formation in D group. It was confirmed that the expressions of VEGF and VEGFR2 in group D were lower than that of the other groups. CONCLUSIONS: Dexamethasone gelatin sponge could significantly reduce the occurrence of epidural scar tissue hyperplasia and adhesion after laminectomy in rats, and its mechanism may be related to the decreased expression of VEGF and VEGFR2.

Securin promotes migration and invasion via matrix metalloproteinases in glioma cells.

Human securin, encoded by pituitary tumor transforming gene 1, is implicated in several oncogenic processes in the pathogenesis of brain tumors, including glioma. The aim of the present study was to examine the effect of securin on the migration and invasion of glioma cells. The results revealed that the overexpression of securin in glioma LN-229 cells significantly increased the invasion and transmigration abilities. By contrast, these abilities were significantly reduced by the downregulation of securin in glioma U373 cells. Furthermore, the results demonstrated that securin overexpression and downregulation significantly increased and decreased the levels of matrix metalloproteinase 2 and 9, respectively. These findings indicate a promotive role for securin in glioma migration and invasion, which may involve the action of matrix metalloproteinases.

Relationships of LDLR genetic polymorphisms with cerebral infarction: a meta-analysis.

This meta-analysis was undertaken to identify the relationships between genetic polymorphisms in the LDLR gene and the risk of cerebral infarction. The Web of Science (1945-2013), the Cochrane Library Database (Issue 12, 2013), PubMed (1966-2013), EMBASE (1980-2013), CINAHL (1982-2013) and the Chinese Biomedical Database (CBM) (1982-2013) were searched for relevant articles without language restrictions. Meta-analysis was conducted using the STATA 12.0 software. Crude odds ratios (OR) with their corresponding 95% confidence interval (CI) were calculated. Eight case-control studies with a total of 4,655 patients with cerebral infarction and 15,920 healthy control subjects were included in our meta-analysis. Five common polymorphisms in the LDLR gene were evaluated, including rs11669576 A > T, rs1433099 C > T, rs5925 C > T, rs688 C > T, rs1122608 T > G in the LDLR gene. The results of this meta-analysis revealed that cerebral infarction patients had a higher frequency of LDLR genetic polymorphisms than that of healthy controls (allele model: OR 1.17, 95% CI 1.05-1.30, P = 0.004; dominant model: OR 1.18, 95% CI 1.05-1.33, P = 0.007; homozygous model: OR 1.50, 95% CI 1.03-2.16, P = 0.032; respectively), especially for the rs11669576 A > T, rs1433099 C > T and rs5925 C > T polymorphisms. Among different ethnic subgroups, the results demonstrated positive correlations between LDLR genetic polymorphisms and an increased risk of cerebral infarction among both Asians and Caucasians under the allele and dominant models (all P < 0.05). Our findings indicate that LDLR genetic polymorphisms may be strongly involved in the pathogenesis of cerebral infarction, especially the rs11669576 A > T, rs1433099 C > T, rs5925 C > T polymorphisms.

Dendritic cell-glioma fusion activates T lymphocytes by elevating cytotoxic efficiency as an antitumor vaccine.

BACKGROUND: Hybrid cells produced by fusions of tumor and dendritic cells (DC) have demonstrated remarkable efficacy for priming the anti-tumor immune response. In the current study, we examined the antitumor activity of cytotoxic T lymphocytes (CTLs) primed in response to a tumor vaccine comprising a glioma-DC fusion as part of a therapeutic against glioma. MATERIAL AND METHODS: Primary cultured glioma cells were fused with peripheral blood DC under conditions of polyethylene glycol (PEG) incubation. Glioma cell suspensions were designated as three groups to include (1) CTL-effective cell group activated by fused cells; (2) CTL-effective cell group stimulated by co-cultured glioma cells and DC cells; and (3) lymphocyte-only group as a control, which was not stimulated by the DC. Cytotoxicity of CTLs on glioma cells was accessed by MTT assay in vitro. RESULTS: Glioma cells with peripheral blood DC were cultured and fused. The killing effect of CTLs pre-activated by fused cells was significantly higher than that of the co-culture CTL group with unsensitized lymphocytes (p < 0.01). The killing activity, as measured by an enhanced efficiency ratio, was increased significantly in the co-cultures of fused cells with CTL groups (p < 0.01). CONCLUSIONS: The glioma-dendritic cell fusion vaccine possessed a more effective anticancer activity by stimulating the effector activity of CTLs.

Comprehensive study on associations between nine SNPs and glioma risk.

AIM: Glioma cancer is the most common type of adult brain tumor. Recent genome-wide association studies (GWAS) have identified various new susceptibility regions and here we conducted an extensive analysis of associations between 12 single nucleotide polymorphisms (SNPs) and glioma risk. METHODS: A total of 197 glioma cases and 197 health controls were selected, and 9 SNPs in 8 genes were analyzed using the Sequenom MassARRAY platform and Sequenom Assay Design 3.1 software. RESULTS: We found the MAF among selected controls were consistent with the MAF from the NCBI SNP database. Among 9 SNPs in 8 genes, we identified four significant SNP genotypes associated with the risk of glioma, C/C genotype at rs730437 and T/T genotype at rs1468727 in ERGF were protective against glioma, whereas the T/T genotype at rs1799782 in XRCC1 and C/C genotype at rs861539 in XRCC3 conferred elevated risk. CONCLUSION: Our comprehensive analysis of nine SNPs in eight genes suggests that the rs730437 and rs1468727 in ERGF, rs1799782 in XRCC1 gene, and rs861539 in XRCC3 gene are associated with glioma risk. These findings indicate that genetic variants of various genes play a complex role in the development of glioma.

[Effects of Newcastle disease virus on the expression of survivin and cell cycle in human tongue squamous carcinoma TSCCa cells].

OBJECTIVE: To investigate the effects of Newcastle disease virus (NDV) infection on the expression of survivin and cell cycle in human tongue squamous carcinoma TSCCa cells. METHODS: The proliferation of TSCCa cells infected with NDV in vitro was evaluated by means of MTT assay, and survivin expression in the infected cells was detected using RT-PCR and Western blotting. Flow cytometry was performed to assess the changes in the cell apoptosis, cell cycle and cell proliferation index (PI) of the cells. RESULTS: NDV infection resulted in decreased survivin expression and increased apoptosis of TSCCa cells, with reduced cell percentage in G2/M and S phases and lowered PI of the cells, showing significant differences from those of the negative control cells (P<0.05). CONCLUSION: NDV infection can inhibit survivin expression, affect the cell cycle of TSCCa cells and induce their apoptosis.