MicroRNA-125a-3p Modulate Amyloid ß-Protein through the MAPK Pathway in Alzheimer's Disease.

BACKGROUND: MicroRNA (miR)-125a-3p is reported to play an important role in some central nervous system diseases, such as Alzheimer's disease (AD). However, a study has not been conducted on the mechanism of miR-125a-3p in the pathological process of AD. METHODS: First, we assessed the expression of miR-125a-3p in AD cohort. Subsequently, we altered the expressions of miR-125a-3p to assess its role in cell viability, cell apoptosis, amyloid-ß (Aß) metabolism, and synaptic activity. Finally, we identified its potential mechanism underlying AD pathology. RESULTS: This study unveiled the potential function of miR-125a-3p through modulating amyloid precursor protein processing. Additionally, miR-125a-3p influenced cell survival and activated synaptic expression through the modulation of Aß metabolism in the mitogen-activated protein kinase (MAPK) pathway via fibroblast growth factor receptor 2. CONCLUSION: Our study indicates that targeting miR-125a-3p may be an applicable therapy for AD in the future. However, more in vitro and in vivo studies with more samples are needed to confirm these results.

Explore the role of CR1 genetic variants in late-onset Alzheimer's disease susceptibility.

BACKGROUND: Complement component (3b/4b) receptor 1 (CR1) is an interesting candidate gene which has a close connection with Alzheimer's disease, and its polymorphisms have been reported to link to the late-onset Alzheimer's disease (LOAD) susceptibility. However, the findings of these related studies are inconsistent. Objective To explore the effect of CR1 genetic variants in LOAD susceptibility. MethodsWe searched relevant studies for the period up to 1 November 2020. And odds ratios (ORs) and their 95% confidence intervals (CIs) were utilized to assess the strength of the association. In addition, we carried out a case-control association study to assess their genetic association. RESULTS: Finally, a total of 30 articles with 30108 LOAD cases and 37895 controls were included. Significant allele frequency between LOAD patients and controls was observed in rs3818361 and rs6656401 (rs3818361, T vs. C: OR,1.18; 95% CI, 1.13-1.23; rs6656401, A vs. G: OR, 1.23; 95% CI, 1.10-1.36). Moreover, these results remain significant in subgroup of rs3818361 in Asia or America (OR,1.26; 95% CI,1.06-1.45; OR, 1.18; 95% CI, 1.13-1.24, respectively) and rs6656401 in Europe (OR = 1.26; 95% CI, 1.09-1.42). In addition, the two single nucleotide polymorphisms were proved to significantly increase LOAD risk in the overall population under the dominant model (OR = 1.12; 95% CI, 1.02-1.21; OR = 1.18, 95% CI, 1.15-1.22, respectively). Our case-control study showed that the distribution of rs6656401 genotype was significant (P = 0.000; OR, 6.889; 95% CI, 2.709-17.520), suggesting the A allele of rs6656401 is the risk allele. CONCLUSION: These available data indicate that rs6656401 in CR1 is significant to increase LOAD risk.

Identification of Potential Gene Signatures Related to Sleep Deprivation.

This study aimed to identify possible therapeutic targets involved in sleep deprivation (SD) risks. GSE77393 data set was acquired from Gene Expression Omnibus database. Functional analysis and protein-protein interaction (PPI) analysis were used to extract the differentially expressed genes (DEGs) between two SD samples and control samples. Moreover, submodule network with the same function was further extracted and the functional enrichment analysis of corresponding genes was carried out. Afterward, the transcriptional regulation analysis and drug-gene interaction were also carried out to identify the essential genes associated with SD susceptibility. Totally, 121 DEGs, including 90 consistently upregulated DEGs and 31 downregulated DEGs, were screened and the results of functional analysis indicated that upregulated genes were related to learning or memory and response to drug, whereas downregulated DEGs were mainly responsible for response to UV and cell differentiation. Moreover, PPI network and submodule analysis revealed that many key genes (FOS and BDNF) were hub genes and the KEGG enrichment analysis found that these genes such as FOS and BDNF were considerably enriched in pathways such as MAPK signaling pathway, HTLV-I infection, and Hepatitis B. In addition, two genes (FOS and BDNF) with a higher degree were found to be key regulators and play important roles in the transcriptional regulator network and drug-gene interactions, suggesting that these two genes were associated with SD development. FOS and BDNF might be served as the potential targets for SD treatment.

Expression and clinical significance of Semaphorin4D in non-small cell lung cancer and its impact on malignant behaviors of A549 lung cancer cells.

This study aimed to explore Semaphrin4D (Sema4D) expression and clinical significance in non-small cell lung cancer (NSCLC), and to define the roles and mechanisms of Sema4D in regulating the malignant behaviors of A549 cells by small interfering RNA (siRNA). Firstly, immunohistochemistry revealed that Sema4D was more frequently expressed in NSCLC than in lung benign lesion (P<0.05) and its overexpression was associated with low differentiation (P<0.05), poor pTNM staging (P<0.05) and occurrence of lymph node (LN) metastasis (P<0.05). Endogenous Sema4D expression was suppressed by Sema4D siRNA in A549 cells overexpressing Sema4D. Protein levels of Sema4D, total Akt and p-Akt were examined by Western blotting. Cell proliferation, migration and invasion abilities were measured by MTT assay and Transwell assay respectively. Results showed that Sema4D siRNA significantly suppressed phosphorylation of AKT in A549 cells, but it did not alter total AKT expression. In addition, efficient down-regulation of SemaD significantly inhibit cell proliferation (P<0.05), migration (P<0.05) and invasion (P<0.05) in A549 cells. These findings suggest that Sema4D might serve as a reliable tool for early prediction of NSCLC poor prognosis. Sema4D could play an important role in promoting tumor proliferation, migration and metastasis in the NSCLC, by influencing the Akt protein phosphorylation. Inhibition of Sema4D may be a useful approach for the treatment of NSCLC.