Research advances on treatment of hepatitis C infection based on RNA interference and microRNA modulation / 浙江大学学报·医学版

Infection with hepatitis C virus (HCV) is one of the major global health problems, approximately 170 million people are infected worldwide. The chronic HCV infection is associated with a high risk of developing liver cirrhosis, hepatocellular carcinoma (HCC) and liver failure. Unfortunately, there is still no effective vaccine or antibodies available for the prevention of infection. RNA interference (RNAi) represents a promising new approach to combat viral infections, and recent developments in the field of gene therapy have increased the feasibility of clinical applications. RNAi techniques have made rapid progress in the basic understanding of HCV biology and revealed numerous new viral and host-cell factors as potential targets for therapy. Together with the improvement of gene delivery technique and the discovery of the critical role of microRNA (miRNA) in HCV infection, RNAi and miRNA-based antiviral strategies hold great promise for the future. In this article, we provide a comprehensive overview of current developments of therapeutic targets of RNAi, liver-targeted delivery systems and the potential applications of miRNAs in treatment of hepatitis C infection.

Physicochemical and sustained drug release properties of calcium phosphate cement/amifostine/cisplatin complex and its effect in repairing bone defect due to tumor resection in rabbits / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the feasibility of using calcium phosphate cement/amifostine complex as an new filling material for repairing bone defect caused by tumor resection.</p><p><b>METHODS</b>Calcium phosphate cement (CPC)/cisplatin/amifostine complex was prepared at the mass ratio of 1000:2:5. The setting time, mechanical strength, and porosity of the complex were determined, and scanning electron microscopy and assessment of sustained drug release and inhibitory effect against osteosarcoma cells were carried out. The degradation of the material and new bone ingrowth were also observed in a rabbit model of femoral bone defect.</p><p><b>RESULTS</b>The setting time, strength, and porosity, appearances under scanning electron microscope, and sustained drug release properties of CPC/cisplatin/amifostine complex were identical to those of CPC, and the integration of amifostine in the complex did not affect the cytotoxicity of cisplatin against the osteosarcoma cells. Pathological evidences of the degradation of the material and new bone ingrowth into the material were observed with the passage of time following its implantation into the bone defect in rabbits.</p><p><b>CONCLUSION</b>The CPC/cisplatin/amifostine complex can be used as a filling material for repairing bone defect caused by tumor resection and eliminating the residual tumor cells in rabbits.</p>

Mice adipose derived Flk-1+ mesenchymal stem cells can ameliorate Duchenne's muscular dystrophy in Mdx mice for their multilineage potential / 中国实验血液学杂志

Duchenne muscular dystrophy (DMD) is a common X-linked disease characterized by widespread muscle damage that invariably leads to paralysis and death. There is currently no therapy for this disease. This study was purposed to investigate the feasibility to use adult adipose-derived mesenchymal stem cells (AD-MSCs) in the therapy of DMD. The Flk-1(+) MSCs were isolated from adipose tissue of adult GFP mice; the phenotype and cell cycle of MSCs were analyzed by flow cytometry; the AD-MSCs were directionally differentiated by myoblast and endotheliablast induction system in vitro and were identified by immumofluorecence staining and RT-PCR; the AD-MSCs were transplanted into CTX-injured mice model or mdx mice (DMD animal model) through tail vein; the distribution and differentiation of AD-MSCs were detected by immunofluorescence staining and RT-PCR respectively, and statistic analysis was performed. The results showed that the Flk-1(+) AD-MSCs could be induced to differentiate into myoblasts and endothelial cells in vitro. After transplanted into CTX-injured mice model or mdx mice, GFP-positive cells could be detected in damaged muscle, and these donor-derived cells were also positive for MHC, vWF, or Pax7. Flk-1(+) AD-MSC transplantation also partly reconstituted the expression of dystrophin, and reduced the percentage of centronucleated myofibers in mdx mice. It is concluded that Flk-1(+) AD-MSCs represent a possible tool for future cell therapy applications in DMD disease, as they can be delivered through the circulation for their potential of muscle homing. And Flk-1(+) AD-MSCs also show the ability to contribute to muscle repair, improvement of blood supply and long term reconstitution of dystrophy muscle.

Potential of human adipose tissue derived adult stem cells differentiate into endothelial cells / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate whether human adipose derived adult stem (hADAS) cells can differentiate into endothelial cells.</p><p><b>METHODS</b>Stem cells were isolated and expanded from adipose tissue and then induced to differentiate into cells of osteogenic, adipogenic and neurogenic lineages in vitro. hADAS cells were induced with vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) to endothelial cells differentiation. hADAS cells were intravenously injected into mouse hindlimb ischemic models to test their ability to differentiate endothelial cells in vivo.</p><p><b>RESULTS</b>hADAS cells were easily isolated and expanded in vitro. They had the ability to differentiate into osteogenic, adipogenic and neurogenic lineages. The cells expressed vascular endothelial growth factor receptor-2 (VEGFR-2, Flk1), and expressed endothelial markers when cultured with VEGF and bFGF. In response to local cues, hADAS cells in vivo differentiate into endothelial cells that contributed to neoangiogenesis in hindlimb ischemia models.</p><p><b>CONCLUSIONS</b>Flk1+ hADAS cells have multipotential not only similar to bone marrow mesenchymal stem cells, but also exhibiting characteristics of endothelial progenitor cells. They may be a potential source of endothelial cells for cellular pro-angiogenic therapies.</p>