ABSTRACT
BACKGROUND:There are many treatment methods for infected bone defects,but there is no first stage treatment method,which has the characteristics of sustained-release,anti-inflammation,osteogenic activity,bone conduction and degradable absorption.OBJECTIVE:To investigate the research progress of bone tissue engineering technique in the treatment of infected bone defects.METHODS:A computer-based retrieval of PubMed,WanFang and CNKI databases was conducted for the articles published from 2000 to 2016,concerning the basic and clinical research on the local application of antibiotics;basic research on infected bone defects with sustained-release of antibiotics;basic studies on the source of seed cells and the osteogenic mechanism;and scaffold materials.A total of 55 eligible articles were included for result analysis.RESULTS AND CONCLUSION:Topical application of antibiotics exhibits different effects in the treatment of osteomyelitis.The development of bone tissue engineering has brought new hope for the treatment of bone defects,and in the meanwhile,selection of excellent seed cells has become a hot and difficult research.A rational combination of antibiotics,seed cells and scaffold materials may provide a new treatment strategy for infected bone defects.
ABSTRACT
<p><b>AIM</b>To investigate the effect of resveratrol on EMMPRIN expression of macrophages.</p><p><b>METHODS</b>Human monocytic cell line THP-1 cells were co-cultured with EMMPRIN-highly-expressed MCF-7 cells; MMP-9 production was assayed by zymography. THP-1 cells were induced by PMA, expression of EMMPRIN was assayed by Western blotting. Cells were treated with resveratrol or PPARgamma agonist--pioglitazone during differentiation, EMMPRIN expression and MMP-9 activity were assayed. U937 cells were co-transfected with PPARy expression and luciferase-coding reporter vector, then cultured with pioglitazone or resveratrol, the activating capability of resveratrol on PPARgamma was evaluated by measuring the luciferase activity. THP-1 cells were pretreated with PPARgamma antagonist--GW9662 before pioglitazone or resveratrol treatment, then assayed for EMMPRIN expression and MMP-9 production.</p><p><b>RESULTS</b>EMMPRIN expression was greatly increased during the differentiation from monocytes to macrophages; co-culturing with MCF-7 cells significantly increased MMP-9 production by monocytes. Both resveratrol and pioglitazone markedly inhibited EMMPRIN expression during monocytes differentiation. Resveratrol significantly activated PPARgamma and GW9662 greatly decreased the effect of resveratrol on EMMPRIN and MMP-9.</p><p><b>CONCLUSION</b>EMMPRIN expression is greatly up-regulated from monocytes to macrophages, which may play a role in inducing MMPs production by monocytes/macrophages. Resveratrol can significantly inhibit EMMPRIN expression via activating PPARgamma, which may be the underlying mechanism of its inhibitory effect on MMPs production by monocytes/macrophages.</p>