ObjectiveTo comprehensively analyze the recent advancements in the field of mesenchymal stem cells (MSCs) derived exosomes (MSCs-exosomes) in tissue repair. MethodsThe literature about MSCs-exosomes in tissue repair was reviewed and analyzed. ResultsExosomes are biologically active microvesicles released from MSCs which are loaded with functional proteins, RNA, and microRNA. Exosomes can inhibit apoptosis, stimulate proliferation, alter cell phenotype in tissue repair of several diseases through cell-to-cell communication. ConclusionMSCs-exosomes is a novel source for the treatment of tissue repair. Further research of MSCs-exosomes biofunction, paracellular transport, and treatment mechanism will help the transform to clinical application.
Objective To review the recent progress of the small intestinal submucosa (SIS) in application research of tissue repair and reconstruction. Methods The domestic and international articles on the SIS were reviewed and summarized. Results As a natural extracellular matrix, SIS has outstanding biological advantages, such as good mechanical property, tissue compatibility, and lower immunogenicity. SIS has been used to repair and reconstruct various types of tissue defects in animal models and clinical application, especially in the treatment of hernia, urinary system disease, and refractory skin trauma. The development of the tissue engineering technology expands the field of SIS repair and reconstruction and promotes the intensive study of SIS. However, the long-term effect of SIS in tissue repair and reconstruction still remains to be further observation, while the cell/SIS material construction by tissue engineering technology also needs more studies. Conclusion SIS has a widely promising application future in the tissue repair and reconstruction.
Objective To review the expression of mechano-growth factor (MGF) and its roles in tissue repairs andregeneration. Methods The l iterature about the expression of MGF and its roles in tissue repairs and regeneration in recentyears was reviewed. Results MGF is sensitive to mechanical stimulation and can be expressed in various tissues/cells. MGF isresponsible for satell ite cell activation, myoblast proliferation, and plays important roles in the treatment of muscle coloboma,prevention of myocardial injury, and neuroprotection. Conclusion The important role of MGF in tissue repairs andregeneration has been identified, however, the detailed mechanisms remain unclear up to now and still need a further study.
Objective To summarize the basic research and the cl inical use of small intestinal submucosa (SIS), which is used as a degradable material for tissue repair. Methods Recent l iterature concerning SIS at home and abroad was extensively reviewed, and current developments of the basic research and the cl inical use of SIS were investigated. Results SIShad many biological advantages in tissue repair, and was used to repair various tissue defects in animal trials. It had successful outcomes in many cl inical trials to repair hernia, anal fistula and Peyronie diseases. And it also had good results at the early stage to treat dilation of the anastomosis, urethroplasty, hypospadias, and other diseases, however, the long-term follow-up was needed. Conclusion SIS is one kind of good material for tissue repair, and has promising future in the cl inical use.
Abstract For the purpose of studying the effects on wound healing of three new bioelectret composites (BC) which are composed ofcollagen polyvinyl alcohol and epidermal growth factor (EGF), 30 rabbits were divided into 5 groups. Three wounds in round shape (1.8 cm in diameter) were made in each side of the back of the rabbits. The wounds of 1～3 groups were treated by one of the three BC respectively, group 4 treated by SDAg, and group 5 were treated by Normal saline as control. From observation of the growth of the granulation tissue, the reepithelization and the pathological assessment, it was shown that the quality of wound healing in all BC treated wounds was better than that in SDAg or the control. It indicated that the BC benefited the wound healing, and this might also be due to its bioelectric effects and the direct effects from growth factor.
Objective To study the cellular biocompatibility, adhesion and proliferation of endothelial outgrowth cells (EOCs) isolated and expanded from rabbit peripheral blood cultured with aligned poly-L-lactic acid (PLLA) nanofibrous scaffolds in vitro so as to provide a basis for the applications of scaffolds biomaterials in tissue repair. Methods Nanofibrous scaffolds of PLLA by electrostatic spinning were modified by hypothermal plasmas body and type Ⅰ collagen was coated onto the materials physically. In vitro, EOCs were cultured on the modified PLLA scaffold. Adhesion and proliferation were surveyed and morphological changes and biocompatibility of seeding cells on PLLA scaffold were observed by growth curves of the cells, fluorescent microscope and scanning electron microscope respectively. Results Fibers with diameters ranging from 300 nm to 400 nm were included in the nanofibrous scaffolds, whose porosities were more than 90%. Absorbance (A) of each scaffold increased gradually after EOCs grew in the absence or presence of random, aligned, or super-aligned PLLA nanofibrous scaffold. Although there was no detectable effect of the random PLLA scaffold on the growth EOCs (Pgt;0.05), both aligned and super-aligned PLLA nanofibrous scaffold had significantly enhanced their growth since the 5th day (P＜0.05). The rates of adhesion in both aligned and super-aligned PLLA nanofibrous scaffold were significantly higher than those of random PLLA scaffold after 12 h and 24 h incubation (P＜0.01). The rates of proliferation after 1 d, 3 d and 7 d incubation in aligned and super-aligned PLLA nanofibrous scaffold were significantly higher than those of random PLLA nanofibrous scaffold (P＜0.05, P＜0.01). EOCs grew well with PLLA scaffold, yet confused and disorderly in random nanofibers. EOCs could attach, extend and proliferate following fibrous orientation in aligned and super-aligned PLLA nanofibrous scaffold, in majority of the fibers were oriented along the longitudinal axis so that a unique aligned topography was formed. Especially super-aligned PLLA nanofibrous had advantageous to keep well on cell morphology. Conclusion EOCs are ideal seeding cells for tissue engineering. EOCs can be adhered well to aligned and super-aligned PLLA nanofibrous scaffold and proliferate, keep well on cell morphology. So this type of PLLA nanofibrous scallfold is proposed to be an optimal candidate material for EOCs transplantation in tissue repair.
ObjectiveTo review the research status on the molecular basis of intervertebral disc degeneration and the repairing effect of platelet-rich plasma. MethodsThe related literature about the molecular basis of intervertebral disc degeneration and the repairing effect of platelet-rich plasma was reviewed, analyzed, and summarized. ResultsThe molecular basis of intervertebral disc degeneration includes genetic influences, cell senescence, decreased matrix production, increased degradative enzyme production, proinflammatory cytokine expression, apoptosis, and neural ingrowth. Platelet-rich plasma can release a series of growth factors to promote intervertebral disc cells proliferation, differentiation, and extracellular matrix synthesis. It can also inhibit proinflammatory effect and apoptosis. ConclusionAlthough the prospect of using platelet-rich plasma to repair intervertebral disc degeneration is encouraging, further studies are still needed.
ObjectiveTo review the mechanisms of bioactive substances of mesenchymal stem cells-derived exosomes (MEX) in tissue repair and analyze the therapeutic values of MEX. MethodRecent relevant literature about MEX for tissue repair was extensively reviewed and analyzed. ResultsThe diameter of exosomes ranges from 30 to 100 nm which contain an abundance of bioactive substances, such as mRNA, microRNA, and protein. The majority of the exact bioactive substances in MEX, which are therapeutically beneficial to a wide range of diseases, are still unclear. ConclusionsBioactive substances contained in the MEX have repairing effect in tissue injury, which could provide a new insight for the clinical treatment of tissue damage. However, further studies are required to investigate the individual differences of MEX and the possible risk of accelerating cancer progression of MEX.