醫(yī)學免費論文:組織工程修復軟骨基質(zhì)蛋白聚糖代謝的初步探討
【摘要】 目的 檢測軟骨修復組織中蛋白聚糖相關(guān)代謝指標,初步探討在軟骨修復過程中基質(zhì)蛋白聚糖的代謝變化以及基質(zhì)金屬蛋白酶(matrix metalloproteinases, MMPs)和蛋白聚糖酶(aggrcanases)的作用。方法 松質(zhì)骨骨基質(zhì)明膠(bone matrix gelatin, BMG)復合同種異體軟骨細胞構(gòu)建組織工程化軟骨,體內(nèi)植入修復兔膝關(guān)節(jié)骨軟骨缺損。術(shù)后6個月取材檢測蛋白聚糖合成表位3-B-3(-)、MMPs、MMPs裂解表位BC-4 以及aggrcanases裂解表位BC-13的表達情況。結(jié)果 在修復組織中,蛋白聚糖合成表位3-B-3(-)表達增加,MMPs及其裂解表位BC-4表達減低,而aggrcanases裂解表位BC-13表達陰性。結(jié)論 利用蛋白聚糖合成表位3-B-3(-)、MMPs、BC-4、BC-13的表達情況可以初步了解修復軟骨組織中蛋白聚糖的代謝變化,修復軟骨組織蛋白聚糖的合成大于分解,MMPs在兔關(guān)節(jié)修復軟骨基質(zhì)蛋白聚糖的基礎(chǔ)代謝和重塑中具有重要作用。
【關(guān)鍵詞】 組織工程;修復;軟骨基質(zhì);蛋白聚糖;基質(zhì)代謝
Research on matrix proteoglycan turnover of tissue engineering repaired cartilageYANG Bo, CAO Jun-ling, ZHANG An, CHEN Jing-hong,ZHANG Zeng-tie, FU Qiang, LIU Fu-qiang, LU Min-ling, LIU Jia-yuan Department of Rehabilitation Medicine and Physiotherapy,the First Affiliated Hospital, Medical School of Xian Jiaotong University, Xian 710061;Institute of Endemic Diseases, Key Laboratory of Environment and Genes Related to Diseases of Ministry of Education, Xian Jiaotong University, Xian 710061, ChinaABSTRACT: Objective To examine matrix proteoglycan metabolic markers and probe into the turnover of matrix proteoglycan and enzyme-mediated role of matrix metalloproteinases (MMPs) and aggrecanases in reparative tissues with tissue engineering cartilage. Methods Tissue-engineered cartilage was constructed by cancellous bone matrix gelatin (BMG) with allogeneic chondrocytes in vitro for 2 weeks, then implanted to repair osteochondral defects of rabbit knee joint. Samples were obtained 6 months later to explore the expressions of 3-B-3(-) epitope, MMPs, MMP-generated epitope BC-4 and aggrecanases-generated epitope BC-13. Results In repaired tissues, the expression of 3-B-3(-) epitope increased, but that of MMPs and MMP-generated epitope BC-4 reduced. There was no expression of aggrecanases-generated epitope BC-13. Conclusion Expressions of 3-B-3(-), MMPs, BC-4 and BC-13 can help probe into the matrix proteoglycan turnover in reparative cartilage tissues. Anabolism exceeds catabolism in the repaired tissues. MMPs play an important role in the conservative baseline turnover of proteoglycan and remodeling of the graft tissues醫(yī).學.全.在.線m.quanxiangyun.cn.
KEY WORDS: tissue engineering; repair; cartilage matrix; proteoglycan; matrix turnover
關(guān)節(jié)骨軟骨損傷的治療一直是骨科臨床的難題之一。軟骨下鉆孔、骨膜以及軟骨膜移植效果都不理想,組織工程軟骨移植治療骨軟骨損傷取得了良好的效果,修復組織主要為透明樣軟骨[1]。但是新生組織的功能較正常關(guān)節(jié)軟骨差,這主要是由于新生軟骨組織沒有達到正常關(guān)節(jié)軟骨基質(zhì)的組織結(jié)構(gòu)和生物化學性能。軟骨基質(zhì)是軟骨特有生理功能的基礎(chǔ),在正常成熟的關(guān)節(jié)軟骨,軟骨細胞外基質(zhì)分子的合成與分解處于動態(tài)平衡,以保證軟骨組織結(jié)構(gòu)和功能的完整性,因此弄清修復軟骨形成過程中基質(zhì)分子代謝的機制對調(diào)控關(guān)節(jié)軟骨的再生和重塑,改善修復軟骨質(zhì)量,促進形成透明軟骨,使其更接近或達到正常關(guān)節(jié)軟骨的性能具有重要的意義[2]。目前對軟骨修復過程中基質(zhì)分子機制的研究還很少,軟骨基質(zhì)分子的不同代謝狀態(tài)可以被不同的抗體特異性識別,如在Ⅱ型膠原的代謝中,CⅡC1R160抗體可特異性地識別軟骨細胞新合成的Ⅱ型膠原前體,而Col2-3/4m則可識別降解的膠原片斷[3-4]。蛋白聚糖代謝的不同狀態(tài)也有不同的抗體識別,3-B-3(-)識別軟骨細胞新合成的未成熟的蛋白聚糖[5],BC-4和BC-13分別識別基質(zhì)金屬蛋白酶(matrix metalloproteinases, MMPs)和蛋白聚糖酶(aggrecanases)在蛋白聚糖球間區(qū)羧基端的裂解位點[6]。利用這些特異性抗體就可以了解修復過程中軟骨基質(zhì)大分子代謝的變化。關(guān)節(jié)軟骨基質(zhì)主要由蛋白聚糖和Ⅱ型膠原組成,成人關(guān)節(jié)軟骨內(nèi)基質(zhì)膠原10年更新一半[7],有報道股骨頭處膠原的更新大約要400年[8],而蛋白聚糖大約每年更新一半,在軟骨生長期或組織修復過程中代謝會更快,因而蛋白聚糖在修復早期能很好地反映軟骨基質(zhì)代謝的變化。本實驗通過構(gòu)建組織工程軟骨移植修復兔膝關(guān)節(jié)骨軟骨缺損,檢測細胞外基質(zhì)蛋白聚糖合成表位3-B-3(-)、MMPs、MMPs裂解表位BC-4以及aggrcanases 裂解表位BC-13的表達情況,初步了解在組織工程修復軟骨過程中細胞外基質(zhì)蛋白聚糖代謝改變以及兩種相關(guān)調(diào)節(jié)酶在修復軟骨基質(zhì)重塑中的作用。