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Mesenchymal stem cells (MSCs)-derived exosomes (Exo) are beneficial in the use of brain damages. Restrictively, the mechanism of Exo expressing miR-124-3p in hypoxic-ischemic brain damage (HIBD) is not completely comprehended. Thereupon, this work was put forward to reveal the action of bone marrow MSCs-derived Exo (BMSCs-Exo) expressing miR-124-3p in the illness. BMSCs were isolated and transfected with miR-124-3p agomir. Then, BMSCs-Exo were extracted and identified. The newborn HIBD rats were injected with miR-124-3p-modified BMSCs-Exo or tumor necrosis factor receptor associated factor 6 (TRAF6)-related vectors. Next, neurological functions, neuron pathological and structural damages, oxidative stress and neuronal apoptosis were observed. miR-124-3p and TRAF6 expression was tested, along with their targeting relationship. miR-124-3p was down-regulated, and TRAF6 was up-regulated in newborn HIBD rats. miR-124-3p targeted TRAF6. BMSCs-Exo improved neurological functions, alleviated neuron pathological and structural damages, suppressed oxidative stress and reduced neuronal apoptosis in newborn HIBD rats, whereas BMSCs-Exo-mediated effects were enhanced by restoring miR-124-3p. Silencing TRAF6 attenuated HIBD in newborn rats, but overexpression of TRAF6 reversed the protective role of miR-124-3p-overexpressing BMSCs-Exo. This work makes it comprehensive that up-regulated exosomal miR-124-3p ameliorates HIBD in newborn rats by targeting TRAF6, which replenishes the potential agents for curing HIBD.

Gliomas are one of the most common and most aggressive types of central nervous system tumor. Angiogenesis is an important basis for the growth of solid tumors, including gliomas, which is regulated by microRNAs (miRNAs). However, the mechanism remains unclear. Recently, it was demonstrated that miR‑24 was upregulated in gliomas, so the aim of the present study is to establish whether the dysregulation of miR‑24 in glioma cells promotes microvascular proliferation of endothelial cells (ECs), and to investigate the potential mechanism. miR‑24 was overexpressed or downregulated in U251 glioma cell line cells using miR‑24 mimics or inhibitors, respectively. Subsequently, the effects of conditional medium from miR‑24 mimic‑ or inhibitor‑transfected U251 cells on cell viability, migration and angiogenesis of human umbilical vein ECs (HUVECs) were examined. The expression levels of vascular endothelial growth factor (VEGF) mRNA, basic fibroblast growth factor (bFGF) mRNA, epidermal growth factor (EGF) mRNA, transforming growth factor (TGF)‑β mRNA, matrix metalloproteinase (MMP)‑2 mRNA and MMP‑9 mRNA, and the mRNA and protein levels of VEGF and TGF‑β in miR‑24 mimic‑ or inhibitor‑transfected U251 cells were obtained by reverse transcription‑quantitative polymerase chain reaction and western blot analysis, respectively. The effects of conditional medium from miR‑24 mimic‑ or inhibitor‑transfected U251 cells on expression levels of VEGF mRNA, TGF‑β mRNA, MMP‑2 mRNA and MMP‑9 mRNA, and mRNA and protein expression levels of VEGF and TGF‑β, and intracellular AKT and β‑catenin signaling in HUVECs were also examined. The results indicated that the conditional medium from miR‑24 mimic‑transfected U251 cells exhibited significantly increased cell viability, cell migration and tube formation of HUVECs. By contrast, the conditional medium from miR‑24 inhibitor‑transfected U251 cells exhibited significantly decreased cell viability, cell migration and tube formation of HUVECs. Enforced expression of miR‑24 in U251 cells may promote the cell viability and angiogenesis of HUVECs. The mRNA expression levels of VEGF, bFGF, EGF, TGF‑β, MMP‑2 and MMP‑9 in U251 cells were significantly increased by miR‑24 mimics. Western blot detection confirmed the increased levels of VEGF and TGF‑β protein expression in U251 by miR‑24 mimics, and the decrease of VEGF and TGF‑β protein expression levels in U251 by miR‑24 inhibitors. The conditional medium from miR‑24 mimic‑transfected U251 cells increased the expression levels of the angiogenesis‑associated factors, including VEGF, TGF‑β, MMP‑2, and MMP‑9. By contrast, reduced expression of miR‑24 in U251 cells may downregulate the expression of those angiogenesis‑associated factors. Thus, miR‑24 in U251 cells may be important in the angiogenesis of HUVECs via VEGF and TGF‑β, and the intracellular signaling of AKT and β‑catenin may be involved in this process.

Recently, microRNAs (miRNAs), a kind of small and non-coding RNA, can target the downstream molecules. Increasing evidence demonstrates that miRNAs meditate the onset and progression of a variety of tumors. In the present study, we carried out gene transfection, western blot, and reverse transcription PCR (RT-PCR) to explore the role of miR-22 in glioblastoma tissues and cell lines. Here, we verified that the expression of miR-22 was downregulated in glioblastoma tissues and cells rather than matched non-tumor tissues and normal human astrocyte (NHA) cells (p < 0.001). By contrast, SIRT1 messenger RNA (mRNA) and protein were upregulated in glioblastoma tissues and cells (p < 0.001). In vitro miR-22 mimics interfered with cell proliferation, migration, and invasion of U87 and U251 cells. Mechanically, the 3'-untranslated regions (3'-UTRs) of SIRT1 were a direct target of miR-22, leading to the decreased expression of SIRT1 protein in U87 and U251 cells. Meanwhile, miR-22 mimics also inhibited the expression of epidermal growth factor receptor (EGFR) and matrix metallopeptidase 9 (MMP9). In conclusion, miR-22 inhibited cell proliferation, migration, and invasion via targeting the 3'-UTR of SIRT1 in the progression of glioblastoma and miR-22-SIRT1 pathway can be recommended as a potential target for treatment of glioblastoma.

Parkinson's disease (PD) is a type of movement disorder caused by loss of dopamine‑producing neurons in the midbrain. In order to identify the synergistic microRNA (miRNA) pattern in PD, miRNA and mRNA double expression profiles of PD were downloaded. Differentially expressed miRNA and mRNA were identified [P<0.01, following false discovery rate (FDR) correction]. A cumulative hypergeometric distribution test was then performed to identify synergistic miRNAs (P<0.01, following FDR correction). Gene ontology (GO) function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway annotations were performed to analyze the miRNA regulatory target genes. Subsequently, a synergistic miRNA network was constructed and miRNAs exhibiting a high degree were identified. In total, 200 differentially expressed miRNA and 2,966 differentially expressed mRNA were identified. In addition, 1,502 synergistic miRNA interactions were identified, and miRNAs regulated 304 target genes in total. The GO and KEGG analysis demonstrated that these target genes were enriched in biosynthetic and cellular biosynthetic processes, the assembly of cellular components in morphogenesis, mitogen‑activated protein kinase signaling, myometrial relaxation and contraction pathways as well as calcium regulation. The miRNA network demonstrated that miR‑627, miR‑634, miR‑514, miR‑563 and miR‑613 had a high degree. miRNA with a high degree may be associated with the pathogenesis of PD and, therefore, may assist in the diagnosis and therapy of PD.

MicroRNAs are known to be involved in carcinogenesis and tumor progression in glioma. Recently, microRNA-372 (miR-372) has been proved to play a substantial role in several human cancers, but its functions in glioma remain unclear. In this study, we confirmed that miR-372 was commonly upregulated in glioma cell lines and tissues. Downregulation of miR-372 markedly inhibited cell proliferation and invasion and induced G1/S arrest and apoptosis. Consistently, the xenograft mouse model also unveiled the suppressive effects of miR-372 knockdown on tumor growth. Further studies revealed that miR-372 modulated the expression of PHLPP2 by directly targeting its 3'-untranslated region (3'-UTR) and that miR-372 expression was inversely correlated with PHLPP2 expression in glioma samples. Silencing of PHLPP2 could rescue the inhibitory effect of miR-372 inhibitor. Moreover, miR-372 knockdown suppressed the phosphorylation levels of the major components of PI3K/Akt pathway including Akt, mTOR, and P70S6K. Taken together, our results suggest that miR-372 functions as an oncogenic miRNA through targeting PHLPP2 in glioma., (© 2014 Wiley Periodicals, Inc.)

Moyamoya disease (MMD) is a cerebrovascular disease characterized by progressive stenosis of the intracranial internal carotid arteries and their proximal branches. However, the etiology of this rare disease remains unknown. Serum microRNA (miRNA) profiles have been screened to identify novel biomarkers of prognostic values. Here, we identified serum miRNAs that might play an important role in the pathogenesis of MMD. A genome-wide miRNA array analysis of two pooled serum samples from patients with MMD and controls revealed 94 differentially expressed serum miRNAs, including 50 upregulated and 44 downregulated miRNAs. In an independent MMD cohort, real-time PCR confirmed that miR-106b, miR-130a and miR-126 were significantly upregulated while miR-125a-3p was significantly downregulated in serum. GO analysis showed that the differentially expressed serum miRNAs were enriched in metabolic processes, transcription and signal transduction. Pathway analysis showed that the most enriched pathway was mTOR signaling pathway with 16 potential, functional targets. Finally, we found that 16 and 13 aberrant serum miRNAs coordinately inhibited RNF213 and BRCC3 protein expression at the posttranscriptional level, respectively, resulting in defective angiogenesis and MMD pathogenesis. To our knowledge, this is the first study to identify a serum miRNA signature in MMD. Modulation of the mechanism underlying the role of serum miRNAs in MMD is a potential therapeutic strategy and warrants further investigations.

Sirtuins are NAD(+)-dependent deacetylases that regulate numerous cellular processes including aging, DNA repair, cell cycle, metabolism, and survival under stress conditions. The roles of sirtuin family members are widely studied in carcinogenesis. However, their roles in glioma remain unclear. Here we report that Sir2 was under expressed in human glioma tissues and cell lines. We found that Sirt2 overexpression decreased cell proliferation and colony formation capacity. In addition, Sirt2 overexpression induced cellular apoptosis via up-regulating cleaved caspase 3 and Bax, and down-regulating anti-apoptotic protein Bcl-2. Sirt2 knockdown obtained opposing results. We showed that Sirt2 overexpression inhibited miR-21 expression, and Sirt2 was not sufficient to reduce cell proliferation and colony formation as well as to induce apoptosis when miR-21 was knocked down in glioma cells. Mechanically, we demonstrated that Sirt2 deacetylated p65 at K310 and blocked p65 binding to the promoter region of miR-21, thus regressing the transcription of miR-21. In summary, Sirt2 is critical in human glioma via NF-κB-miR-21 pathway and Sirt2 activator may serve as candidate drug for glioma therapy., (Copyright © 2013 Elsevier Inc. All rights reserved.)