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Xie H.,Huazhong University of Science and Technology | Wang Z.,Shanghai JiaoTong University | Zhang L.,Central Hospital of Jingzhou | Lei Q.,Huazhong University of Science and Technology | And 5 more authors.
PeerJ | Year: 2016

One of the major challenges of bone tissue engineering applications is to construct a fully vascularized implant that can adapt to hypoxic environments in vivo. The incorporation of proangiogenic factors into scaffolds is a widely accepted method of achieving this goal. Recently, the proangiogenic potential of mesenchymal stem cell-derived microvesicles (MSC-MVs) has been confirmed in several studies. In the present study, we incorporated MSC-MVs into alginate-polycaprolactone (PCL) constructs that had previously been developed for bone tissue engineering applications, with the aim of promoting angiogenesis and bone regeneration. MSC-MVs were first isolated from the supernatant of rat bone marrow-derived MSCs and characterized by scanning electron microscopic, confocal microscopic, and flow cytometric analyses. The proangiogenic potential of MSC-MVs was demonstrated by the stimulation of tube formation of human umbilical vein endothelial cells in vitro. MSC-MVs and osteodifferentiated MSCs were then encapsulated with alginate and seeded onto porous three-dimensional printed PCL scaffolds. When combined with osteodifferentiated MSCs, the MV-alginate-PCL constructs enhanced vessel formation and tissue-engineered bone regeneration in a nude mouse subcutaneous bone formation model, as demonstrated by micro-computed tomographic, histological, and immunohistochemical analyses. This MV-alginate-PCL construct may offer a novel, proangiogenic, and cost-effective option for bone tissue engineering. © 2016 Xie et al. Source

Chu B.,Tsinghua University | Xiong J.,Central Hospital of Jingzhou | Wang M.-B.,Tsinghua University | Li X.-L.,Tsinghua University | She Z.-D.,Tsinghua University
Advanced Materials Research | Year: 2013

The solidification time of injectable bone cement should be fit for the clinical application. This research find out the effect of the amount of water- absorbent agent and water-retaining agent. The optimal ratio was be determined. The hydroxyapatite fibers with strontium were added into the CPC. The mechanical property, cytotoxicity test, SEM morphology, XRD and degradation performance in vitro were characterized, respectively. The results show the CPC had the solidification time of 12min when the ratio as below: β-TCP 55.5%, Ca(H2PO4)2·H2O (MCPM)36%, MgHPO4·3H2O 5%, MgSO41%, Sodium pyrophosphate2.5%. The main components of solidify CPC were hydroxyapatite(HA) and dicalcium phosphate dihydrate(DCPD). The materials had a good Anti-collapsing performance and the degradation rate up to 16.72% after 9 weeks. The mechanical property of composite materials which combined with hydroxyapatite fibers with strontium has been improved, and the cell proliferation rate is also higher than common CPC. This study shows a potentially effective method to improve the mechanical property and the biological activity of calcium phosphate cement. © (2013) Trans Tech Publications, Switzerland. Source

Xie H.,Huazhong University of Science and Technology | Sun L.,Hebei Medical University | Zhang L.,Central Hospital of Jingzhou | Liu T.,Huazhong University of Science and Technology | And 9 more authors.
Stem Cells International | Year: 2016

Mesenchymal stem cells (MSCs) are known to support the characteristic properties of hematopoietic stem and progenitor cells (HSPCs) in the bone marrow hematopoietic microenvironment. MSCs are used in coculture systems as a feeder layer for the ex vivo expansion of umbilical cord blood (CB) to increase the relatively low number of HSPCs in CB. Findings increasingly suggest that MSC-derived microvesicles (MSC-MVs) play an important role in the biological functions of their parent cells. We speculate that MSC-MVs may recapitulate the hematopoiesis-supporting effects of their parent cells. In the current study, we found MSC-MVs containing microRNAs that are involved in the regulation of hematopoiesis. We also demonstrated that MSC-MVs could improve the expansion of CB-derived mononuclear cells and CD34+ cells and generate a greater number of primitive progenitor cells in vitro. Additionally, when MSC-MVs were added to the CB-MSC coculture system, they could improve the hematopoiesis-supporting effects of MSCs. These findings highlight the role of MSC-MVs in the ex vivo expansion of CB, which may offer a promising therapeutic approach in CB transplantation. © 2016 Hui Xie et al. Source

Lu H.-G.,Central Hospital of Jingzhou | Zhan W.,Shanghai Changzheng Hospital | Yan L.,Central Hospital of Jingzhou | Qin R.-Y.,Henan University | And 9 more authors.
Molecular Medicine Reports | Year: 2014

Histone deacetylases (HDACs) are important in chromatin remodeling and epigenetic regulation of gene expression. Histone deacetylase inhibitors (HDACi) have highly effective anti-metastatic and anti-angiogenic activity in various types of cancer, while the molecular mechanisms involved in this process are not fully understood. In the present study, trichostatin A (TSA), a HDACi, was found to suppress MCF-7 breast carcinoma cell invasion and upregulate TET1 expression in a dose-dependent manner. TET1, a dioxygenase involved in cytosine demethylation, is downregulated during breast cancer progression. TET1 knockdown in MCF-7 cells facilitates cell invasion, inhibits the expression of tissue inhibitors of metalloproteinase 2/3 (TIMP2/3) and promotes matrix metalloproteinases (MMP) 2/9 transcriptional activity. Importantly, TET1 depletion impaired the inhibitory effect of TSA on breast cancer cell invasion. Together, these results illustrated a mechanism by which TET1 partially mediates HDACi elicited suppression of breast cancer invasion. Source

Jin Z.,Central Hospital of Jingzhou | Yan W.,Central Hospital of Jingzhou | Jin H.,Central Hospital of Jingzhou | Ge C.,Central Hospital of Jingzhou | Xu Y.,Central Hospital of Jingzhou
Oncology Letters | Year: 2016

Worldwide, colon cancer is the third most common cancer in terms of incidence, following lung and breast cancer. Resistance to psoralidin frequently occurs following its use as an anticancer treatment. However, the mechanisms underlying the effects of psoralidin on colon cancer, remain to be elucidated. Hence, the present study investigated the anticancer effects and potential mechanism of action of psoralidin on SW480 human colon cancer cells. In the present study, an MTT assay was performed to measure the viability of SW480 cells. Additionally, an Annexin V-fluorescein isothiocyanate/propidium iodide apoptosis detection kit, DAPI staining assay and caspase-3 colorimetric assay kits were used to analyze the cellular apoptosis of SW480 cells. The nuclear factor-κB (NF-κB) p65 activity and B-cell lymphoma-2 (Bcl-2)/Bcl-2-associated X protein (Bax) protein expression of SW480 cells was detected using NF-κB colorimetric assay kits and western blot analysis, respectively. Bcl-2 inhibitor ABT-737 was added to SW480 cells and the subsequent effects and mechanism of action of psoralidin on SW480 colon cancer cells was studied. In the present study, psoralidin reduced SW480 cell viability and enhanced the cellular apoptosis of SW480 cells in a dose-dependent manner. Caspase-3 activity of SW480 cells was increased following treatment with psoralidin. Additionally, psoralidin was able to reduce the NF-κB p65 activity of SW480 cells. Furthermore, psoralidin was able to reduce Bcl-2 protein expression and increase Bax protein expression in SW480 cells. Notably, Bcl-2 inhibitor was observed to enhance the effects of psoralidin on SW480 cells. The results of the present study suggest that psoralidin may be a candidate drug for the treatment of colon cancer by inhibition of the NF-κB and Bcl-2/Bax signaling pathways. © Spandidos Publications 2015. All rights reserved. Source

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