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Ichikawa T.,University of South Carolina | Li J.,University of South Carolina | Dong X.,University of South Carolina | Potts J.D.,University of South Carolina | And 3 more authors.
Biochemical and Biophysical Research Communications | Year: 2010

Deubiquitinating enzymes (DUBs) appear to be critical regulators of a multitude of processes such as proliferation, apoptosis, differentiation, and inflammation. We have recently demonstrated that a DUB of ubiquitin carboxyl terminal hydrolase L1 (UCH-L1) inhibits vascular lesion formation via suppressing inflammatory responses in vasculature. However, the precise underlying mechanism remains to be defined. Herein, we report that a posttranscriptional up-regulation of UCH-L1 provides a negative feedback to tumor necrosis factor alpha (TNFα)-mediated activation of extracellular signal-regulated kinases (ERK) and proliferation in vascular smooth muscle cells (VSMCs). In rat adult VSMCs, adenoviral over-expression of UCH-L1 inhibited TNFα-induced activation of ERK and DNA synthesis. In contrast, over-expression of UCH-L1 did not affect platelet derived growth factor (PDGF)-induced VSMC proliferation and activation of growth stimulating cascades including ERK. TNFα hardly altered UCH-L1 mRNA expression and stability; however, up-regulated UCH-L1 protein expression via increasing UCH-L1 translation. These results uncover a novel mechanism by which UCH-L1 suppresses vascular inflammation. © 2009 Elsevier Inc. All rights reserved. Source


Liu H.-B.,Guangxi University | Lv P.-R.,Guangxi University | He R.-G.,Guangxi University | Yang X.-G.,Guangxi University | And 8 more authors.
Cellular Reprogramming | Year: 2010

Xenotransplantation is a rapidly expanding field of research, and cloned miniature pigs are considered to be good model animals for its development. Although many animal species have been cloned, the success rate is very low, especially in the pig. To optimize the protocols for somatic cell nuclear transfer in the Guangxi Bama minipig, the relationship between cell cycle synchronization and nuclear histone acetylation levels were investigated. The results showed that the cells were efficiently synchronized by either serum starvation or contact inhibition. The level of nuclear histone acetylation in G0/G1 donor cells had similar variation trends in serum starvation and contact inhibition groups. When the synchronized donor cells were introduced into the enucleated oocytes, 8.8% (serum starvation group) or 9.7% (contact inhibition group) of the reconstructed embryos developed to blastocysts. After embryo transfer, one healthy male Guangxi Bama minipig was obtained. To evaluate the fertility of the cloned pig and its offspring, a series of mating experiments were done. Ninety-eight F1 generation crossbred piglets were born, of which 93 piglets survived. Also, the F1 pigs gave birth to 22 F2 generation piglets, of which 14 piglets survived. In conclusion, a Guangxi Bama minipig was successfully cloned from cultured newborn male gonad fibroblast cells, and the cloned minipig and its offspring had normal fertility. © 2010, Mary Ann Liebert, Inc. Source


Tang J.,Chinese Institute of Clinical Medicine | Tang J.,Yunyang Medical College | Tang J.,Hubei Key Laboratory of Embryonic Stem Cell Research | Wang J.,Chinese Institute of Clinical Medicine | And 13 more authors.
Molecular and Cellular Biochemistry | Year: 2010

Gene and stem-cell therapies hold promise for the treatment of ischemic cardiovascular disease. Combined stem cell, chemokine, and angiogenic growth factor gene therapy could augment angiogenesis, and better improve heart function in the infarcted myocardium. In order to prove this action, we established the animal model of myocardial infarction (MI) was by occlusion of the left anterior descending artery in rats. Seven days after surgery, 5.0 × 106 Ad-EGFP-MSC, 5.0 × 106 Ad-SDF-1-MSC, 5.0 × 106 Ad-VEGF-MSC, or 5.0 × 106 Ad-SDF-VEGF-MSC (Ad-SDF-1-VEGF-MSC) suspension in 0.2 ml of serum-free medium was injected into four sites in the infarcted hearts. Results showed that MSCs transfected with Ad-VEGF and Ad-SDF-1 produced more SDF-1 and VEGF protein than MSCs alone, the increased protein levels of VEGF and SDF-1 activated Akt in MSCs transfected with Ad-VEGF and Ad-SDF-1, and improved the survival capability of the MSCs in vitro and in vivo. These transplanted cells showed that the characteristic phenotype of cardiomyocyte (e.g., cTnt) and endothelial cells (e.g., CD31). Four weeks after transplantation, reduced infarct size and fibrosis, greater vascular density, and a thicker left ventricle wall were observed in Ad-SDF-VEGF-MSC group. Measurement of hemodynamic parameters showed an improvement in left ventricular performance in Ad-SDF-VEGF-MSC group compared with other groups. These results demonstrated that combination of chemokine and angiogenic factor gene and stem cells could enhance angiogenesis and improves cardiac function after acute myocardial infarction in rats. © 2010 Springer Science+Business Media, LLC. Source


Tang J.,Chinese Institute of Clinical Medicine | Tang J.,Yunyang Medical College | Tang J.,Hubei Key Laboratory of Embryonic Stem Cell Research | Wang J.,Chinese Institute of Clinical Medicine | And 13 more authors.
Molecules and Cells | Year: 2010

Mesenchymal stem cells (MSCs) are a promising source for cell-based treatment of myocardial infarction (MI), but existing strategies are restricted by low cell survival and engraftment. We examined whether SDF-1 transfection improve MSC viability and paracrine action in infarcted hearts. We found SDF-1-modified MSCs effectively expressed SDF-1 for at least 21days after exposure to hypoxia. The apoptosis of Ad-SDF-1-MSCs was 42% of that seen in Ad-EGFP-MSCs and 53% of untreated MSCs. In the infarcted hearts, the number of DAPI-labeling cells in the Ad-SDF-1-MSC group was 5-fold that in the Ad-EGFP-MSC group. Importantly, expression of antifibrotic factor, HGF, was detected in cultured MSCs, and HGF expression levels were higher in Ad-SDF-MSC-treated hearts, compared with Ad-EGFP-MSC or control hearts. Compared with the control group, Ad-SDF-MSC transplantation significantly decreased the expression of collagens I and III and matrix metalloproteinase 2 and 9, but heart function was improved in d-SDF-MSC-treated animals. In conclusion, SDF-1-modified MSCs enhanced the tolerance of engrafted MSCs to hypoxic injury in vitro and improved their viability in infarcted hearts, thus helping preserve the contractile function and attenuate left ventricle (LV) remodeling, and this may be at least partly mediated by enhanced paracrine signaling from MSCs via antifibrotic factors such as HGF. © 2010 KSMCB. Source

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