ABSTRACT
BACKGROUND: Our previous study demonstrated that bone marrow mesenchymal stem cells (MSCs) presented with a low survival rate and newly formed vascular-like structures was sparsely distributed in the local infarct tissues after cell transplantation, which certainly impaired the therapeutic efficacy. Long non-coding RNA-H19 (lncRNA-H19) has been confirmed to be associated with MSCs differentiation and mediate vascularization. OBJECTIVE:To observe the influence of lncRNA-H19 on the survival and vascularization potential of MSCs in vitro and to explore the possible mechanism. METHODS:MSCs were obtained and cultured in vitro.Cells were divided into five groups:MSCs+H19,MSCs+H19 negative control (MSCs+H19 NC), MSCs+si-H19, MSCs+si-H19 negative control (MSCs+si-H19 NC) and MSCs groups. MSCs+H19 and MSCs+H19 NC groups were transfected with lncRNA-H19 and lncRNA-H19 scramble RNA respectively, while MSCs+siH19 and MSCs+si-H19 NC groups were transfected with lncRNA-H19 siRNA and lncRNA-H19 siRNA scramble respectively. Cells were cultured under hypoxic-ischemic condition (serum-free medium, 1% O2) for 24 hours. Then, cell proliferation and apoptosis were evaluated using MTS and TUNEL, respectively. Cell supernatant from each experimental group was further co-cultured with human umbilical vein endothelial cells to induce vascularization. The expression of vascular endothelial growth factor A (VEGFA) was thereafter detected using western blot assay. RESULTS AND CONCLUSION: Compared with MSCs+H19 NC and MSCs groups, MSCs+H19 group presented with significantly higher proliferation rate, lower apoptosis percentage and a larger number of vascular branches on matrigel (P < 0.01). There was a significantly higher expression of VEGFA in the MSCs+H19 group than MSCs+H19 NC and MSCs groups. Compared with the MSCs and MSCs+si-H19 NC groups, MSCs+H19 group presented with significantly lower proliferation rate, higher apoptosis percentage and a less number of vascular branches on matrigel (P < 0.01). In addition, VEGFA expression was distinctly downregulated in the MSCs+si-H19 group in comparison with the MSCs+si-H19 NC and MSCs groups. These findings indicate that lncRNA-H19 effectively promotes MSCs survival and vascularization under hypoxic-ischemic condition in vitro,and this effect may be associated with the upregulation of VEGFA.
ABSTRACT
BACKGROUND:All-natural cardiac deceliularized scaffold material has macroscopic and microstructure,matrix components and vascular network distribution similar to the receptor,which is an ideal material for heart tissue engineering.OBJECTIVE:To summarize the preparation methods,composition characteristics,biological characteristics and the latest research progress of cardiac decellularized matrix scaffold.METHODS:Relevant articles published from January 2008 to April 2017 were searched in PubMed and Wanfang databases using the keywords of "heart,cardiac muscle,myocardial tissue,decellularized matrix" in English and Chinese,respectively.Finally,50 representative articles (44 in English and 6 in Chinese) were included with the exception of the articles that were associated with cardiac valves.RESULTS AND CONCLUSION:Currently,the methods of preparing cardiac decellular matrix scaffolds include physical processing,chemical method and biological treatment (enzymatic method).Cardiac extracellular matrix scaffolds mainly contain Ⅰ,Ⅲ and Ⅳ collagen,glycosaminoglycans,fibronectin,laminin and a small amount of growth factors.At present,the application of the decellular matrix in myocardial tissue engineering includes three directions:the "band-aid" myocardial tissue engineering study based on decellular matrix lamella;the study of the myocardial tissue engineering on injectable myocardial tissue engineering based on the decellular matrix;and the study of decellularized-recellularized artificial cardiac reengineering based on the cardiac all-organ.Although some successful experience has been achieved in the stents,their use in the cardiac replantation still has many problems to be solved.
ABSTRACT
BACKGROUND: In recent years, it has shown that there exist some endogenous cardiac stem cells in the heart. What has been confirmed is that this kind of cells can differentiate into cardiomyocytes to repair the damaged myocardium and improve the cardiac function. OBJECTIVE: To review the current methods of promoting the differentiation of cardiac stem cells into cardiomyocytes. METHODS: PubMed database was searched by computer for articles addressing the differentiation of cardiac stem cells in the last 10 years, using the keywords of "cardiac stem cells, cardiac progenitor cells, differentiation". Finally, 64 English articles were included in result analysis. RESULTS AND CONCLUSION:Recent studies have shown that the differentiation efficiency of cardiac stem cells can be promoted in vivo by introducing cytokines,micro-RNA,and some physicochemical methods,which consequently enhances the therapeutic efficacy of cardiac stem cell transplantation for myocardial infarction.
ABSTRACT
BACKGROUND: Intervertebral disc degeneration (IDD) is a common cause of low back pain. Microenvironmental and cytological changes of intervertebral disc are main factors inducing disc degeneration. However, the underlying mechanism still remains unclear.OBJECTIVE: To review the application of platelet rich plasma (PRP) in the treatment of IDD.METHODS: First, the article structure was designed, and then WanFang and CNKI databases were retrieved for related articles using Chinese and English keywords. After analyzing the abstract and main body, the eligible articles were enrolled according to the inclusion and exclusion criteria.RESULTS AND CONCLUSION: Surgical treatment has achieved remarkable outcomes in the treatment of middle- and late-stage IDD. However, there is still no good conservative therapy for early degeneration. PRP has been extensively applied in the treatment of IDD due to its improvement in tissue healing and regeneration. PRP has been proved to be capable of effectively delaying and even reversing IDD through cytology tests and animal experiments. Some clinical trials have shown that PRP treatment can ease low back pain, while others have demonstrated that the combination of PRP and other biological treatments can significantly improve IDD. Nowadays, most of the experiments are limited in the study of cytology and zoology rather than clinical trials, and there is still no unified standard for extraction method, dose and optimal injection time of PRP. Moreover, there is little reported on its side effects. Consequently, the curative effect of PRP for IDD needs to be verified further.