CVB对OL细胞和OL/BDV细胞I型IFN信号转导途径的影响

探讨柯萨奇病毒(coxsackievirus, CVB)对人类少突胶质细胞(oligodendrocyte, OL)和博尔纳病病毒(Borna disease virus, BDV)持续感染的OL细胞(OL/BDV)中I型干扰素(interferon, IFN)、microRNA-155(miR-155)表达以及干扰素调节因子(interferon regulatory factor, IRF)7细胞定位的影响。CVB感染OL细胞和OL/BDV细胞0、2、4、6、12和24 h,qPCR检测I型IFN mRNA和miR-155表达水平。OL细胞和OL/BDV细胞分别转染IRF7-EGFP质粒,CVB感染4 h,观察IRF7细胞定位情况。CVB感染OL细胞2、4、12和24 h,IFN-αmRNA和miR-155表达水平显著增加,IFN-βmRNA表达水平在4、12和24 h显著增加;CVB感染OL/BDV细胞IFN-α和IFN-βmRNA表达水平除0 h均显著增加,但miR-155表达仅在12和24 h显著增加。CVB感染OL细胞和OL/BDV细胞4 h,IRF7绿色荧光蛋白由细胞浆转移至细胞核内。综上所述,CVB可诱导OL细胞和OL/BDV细胞I型IFN、miR-155的表达,促进IRF7入核,从而激活I型IFN信号转导途径。     

Retracted: Suppression of microRNA-342-3p increases glutamate transporters and prevents dopaminergic neuron loss through activating the Wnt signaling pathway via p21-activated kinase 1 in mice with Parkinson's disease

Development of effective therapeutic drugs for Parkinson's disease (PD) is of great importance. Aberrant microRNA (miRNA) expression has been identified in postmortem human PD brain samples, in vitro and in vivo PD models. However, the role of miR-342-3p in PD has been understudied. The study explores the effects of miR-342-3p on expression of glutamate (Glu) transporter, and dopaminergic neuron apoptosis and proliferation by targeting p21-activated kinase 1 (PAK1) through the Wnt signaling pathway in PD mice. After establishment of PD mouse models, gain- or loss-of-function assay was performed to explore the functional role of miR-342-3p in PD. Number of apoptotic neurons and Glu concentration was then determined. Subsequently, PC12 cells were treated with miR-342-3p mimic, miR-342-3p inhibitor, dickkopf-1 (DKK1), and miR-342-3p inhibitor + DKK1. The expression of miR-342-3p, PAK1, the Wnt signaling pathway-related and apoptosis-related genes, Glutamate transporter subtype 1 (GLT-1), l -glutamate/ l -aspartate transporter (GLAST), tyrosine hydroxylase (TH) was measured. Also, cell viability and apoptosis were evaluated. PD mice exhibited increased miR-342-3p, while decreased expression of PAK1, GLT-1, GLAST, TH, and the Wnt signaling pathway-related and antiapoptosis genes. miR-342-3p downregulation could promote expression of PAK1, the Wnt signaling pathway-related and antiapoptosis genes. GLT-1, GLAST, and TH as well as cell viability, but reduce cell apoptosis rate. The results indicated that suppression of miR-342-3p improves expression of Glu transporter and promotes dopaminergic neuron proliferation while suppressing apoptosis through the Wnt signaling pathway by targeting PAK1 in mice with PD.     

Reversine promotes browning of white adipocytes by suppressing miR-133a

Brown adipocytes are characterized by a high number of uncoupling protein 1 (UCP1)-positive mitochondrial content and increased thermogenic capacity. As UCP1-enriched cells can consume lipids by generating heat, browning of white adipocytes is now highlighted as a promising approach for the prevention of obesity and obesity-associated metabolic diseases. Upon cold exposure or β-adrenergic stimuli, downregulation of microRNA-133 (miR-133) elevates the expression levels of PR domain containing 16 (Prdm16), which has been shown to be a brown adipose determination factor, in brown adipose tissue and subcutaneous white adipose tissues (WAT). Here, we show that treatment of reversine to white adipocytes induces browning via suppression of miR-133a. Reversine treatment promoted the expression of brown adipocyte marker genes, such as Prdm16 and UCP1, increasing the mitochondrial content, while decreasing the levels of miR-133a and white adipocyte marker genes. Ectopic expression of miR-133a mimic reversed the browning effects of the reversine treatment. Moreover, intraperitoneal administration of reversine in mice upregulated thermogenesis and resulted in resistance to high-fat diet-mediated weight gain as well as browning of subcutaneous and epididymal WAT. Taken together, we found a novel way to promote browning of white adipocytes through downregulation of miR-133a followed by activation of Prdm16, with a synthetic chemical, reversine.     

MicroRNA-133b抑制人横纹肌肉瘤细胞增殖与迁移的研究

该研究首先通过Real-time RT-PCR检测发现,microRNA-133b在人横纹肌肉瘤细胞RD和A204中的表达量比正常肌肉组织中的表达量明显降低,再通过阳离子脂质体介导的方法将microRNA-133b转染入横纹肌肉瘤细胞RD和A204细胞中,并应用MTS法、Transwell法研究发现,microRNA-133b可明显抑制RD和A204细胞的增殖与迁移;采用Western blot法检测转染后细胞内与增殖、迁移及细胞周期相关的蛋白表达,发现microRNA-133b能下调RD和A204细胞中的LIMand SH3 protein 1（LASP1）、c-MET、p-MET、p-AKT、p-ERK1/2、p-Rb的表达水平,并降低RD和A204细胞中细胞周期蛋白CDK4和CDK6表达量。该研究表明,microRNA-133b是通过下调LASP1、c-MET和p-MET的表达水平,影响c-MET下游信号分子p-AKT、p-ERK1/2的表达水平,同时还下调细胞周期相关蛋白如CDK4、CDK6、p-Rb等的表达,从而影响RD和A204细胞的增殖与迁移。     

miR-17-5p promotes proliferation and epithelial-mesenchymal transition in human osteosarcoma cells by targeting SRC kinase signaling inhibitor 1

MicroRNA-17-5p (miR-17-5p) and epithelial-mesenchymal transition (EMT) have been reported to participate in the development and progression of multiple cancers. However, the relationship between the miR-17-5p and EMT in osteosarcoma (OS) is still poorly understood. This study was to investigate the effects of the miR-17-5p and its potential mechanism in regulating proliferation, apoptosis, and EMT of human OS. Quantitative real-time PCR was used to detect the miR-17-5p and SRC kinase signaling inhibitor 1 (SRCIN1) messenger RNA expression in OS specimens and cell lines. After transfection with miR-17-5p inhibitors, proliferation, apoptosis, migration, and invasion of OS cells were assessed by using the Cell Counting Kit-8, the annexin V-FITC apoptosis, wound-healing, and transwell assays. The SRCIN1 was validated as a target of the miR-17-5p through bioinformatics algorithms and luciferase reporter assay. Moreover, the expression of EMT markers, E-cadherin, N-cadherin, and Snail was identified by the Western blot analysis. MiR-17-5p was significantly upregulated in OS tumor samples and cell lines. It inhibited proliferation and EMT, and promoted apoptosis in OS. The SRCIN1 was identified as a direct target of the miR-17-5p. Silenced miR-17-5p could change the expression of EMT markers, such as upregulating the expression of E-cadherin, and downregulating the expression of N-cadherin and Snail through targeting the antioncogenic SRCIN1. These findings suggest that the miR-17-5p promotes cell proliferation, and EMT in human OS by directly targeting the SRCIN1, and reveal a branch of the miR-17-5p/SRCIN1/EMT signaling pathway involved in the progression of OS.     

Long non-coding RNA ZNF667-AS1 retards the development of esophageal squamous cell carcinoma via modulation of microRNA-1290-mediated PRUNE2

Abnormal long non-coding RNAs (lncRNAs) have been detected in esophageal squamous cell carcinoma (ESCC). Here, we focused on lncRNA ZNF667-AS1 and its downstream mechanism in ESCC progression. Differentially expressed lncRNAs in ESCC were predicted by bioinformatics analysis. ZNF667-AS1, microRNA-1290 (miR-1290), and prune homolog 2 with BCH domain (PRUNE2) expression was determined with their relationship in cell biological processes analyzed also by means of gain- and loss-of-function assays. Xenograft mouse models were performed to re-produce the in vitro findings. We found a decline in ZNF667-AS1 expression in ESCC tissues and cell lines. ZNF667-AS1 overexpression indicated a favorable prognosis of ESCC sufferers. ZNF667-AS1 overexpression suppressed ESCC cell malignant potentials. ZNF667-AS1 reduced miR-1290 to result in upregulation of the miR-1290 target gene PRUNE2. The inhibiting property of ZNF667-AS1 on the malignant characteristics of ESCC cells was achieved by disrupting the miR-1290-mediated downregulation of PRUNE2. ZNF667-AS1 suppressed the tumorigenesis of ESCC in vivo. Collectively, our study demonstrates that ZNF667-AS1 can function as a tumor suppressor in ESCC by upregulating PRUNE2 and downregulating miR-1290.     

A hidden threshold in motor neuron gene networks revealed by modulation of miR-218 dose

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MicroRNA-92a -mediated endothelial to mesenchymal transition controls vein graft neointimal lesion formation

PurposeLong-term failure of vein grafts due to neointimal hyperplasia remains an important problem in coronary artery bypass graft surgery. Endothelial to mesenchymal transition (EndMT) contributes to vein graft vascular remodeling. However, there is little study on microRNA-mediated EndMT contributions to neointimal formation in vein graft. We hypothesized that microRNA-92a (miR-92a) might play an important role in determining EndMT contributions to neointimal formation.MethodsmiR-92a and EndMT-related proteins detected by qRT-PCR and Western blot in vitro and in vivo. Adeno-associated virus 6 (AAV6) delivery gene therapy was used to inhibit neointimal formation in vivo. The intimal hyperplasia of vein grafts was measured by HE staining, the expression of EndMT-related protein in vein grafts was measured by immunofluorescence. Immunohistochemistry and luciferase assay were used to detect potential targets of miR-92a.ResultsThe expression of miR-92a was found to be upregulated in neointimal hyperplasic lesions after vein grafting. Using cultured human umbilical vein endothelial cells (HUVECs), we show that TGF-β1 treatment of HUVECs significantly increased miR-92a expression and induced EndMT, characterized by suppression of endothelial-specific markers (CD31 and VE-cadherin) and an increase in mesenchymal-specific markers (a-SMA and vimentin), while inhibition of miR-92a expression blunted EndMT in cultured HUVECs. Furthermore, AAV6 mediated miR-92a suppression gene therapy effectively resulted in decreased EndMT and less neointimal formation in vein grafts in vivo. We further identified that integrin alpha 5 (ITGA5) is a potential target gene involved in the development of neointima formation in these vein grafts.ConclusionThis data suggests that neointimal formation does not solely rely on vascular smooth muscle cell phenotypic switching but is also related to EndMT, and miR-92a-mediated EndMT is an important mechanism underlying neointimal formation in vein grafts.