功能化聚乳酸-羟基乙酸共聚物基骨组织再生诱导膜的制备及其在大鼠颌骨缺损重建中的应用

Preparation of functional poly-(lactic acid-co-glycolic acid)-based guided bone-regeneration membrane and its ap‐plication in the reconstruction of mandibular defects in rats

目的制备具有抑制纤维化及抑菌作用的功能化复合静电纺丝纤维膜,初步探究其对大鼠颌骨缺损的修复作用。方法通过静电纺丝技术制备负载环状精氨酸-甘氨酸-天冬氨酸序列、奥硝唑及纳米羟磷灰石(n-HA)的聚乳酸-羟基乙酸共聚物纤维膜作为诱导骨组织再生作用的功能层(GBRL);通过流延法制备具有支撑作用及隔离不同功能层作用的致密膜层(BL);通过静电纺丝技术制备具有抑制纤维化作用的聚(对氧环己酮-L-苯丙氨酸)纤维膜作为抑制纤维化功能层(AFL)。应用扫描电子显微镜对复合膜形态进行表征观察,应用细胞计数盒(CCK)-8法研究不同功能层对MC3T3-E1及L929细胞增殖的影响;应用抑菌圈测试法研究复合膜对牙龈卟啉单胞菌增殖的抑制作用。构建大鼠下颌骨骨缺损模型,研究复合膜对骨缺损组织的修复作用,并与临床常用的胶原口腔修复膜的修复作用进行比较。结果成功制备具有多孔结构的纤维功能层,GBRL层可支持MC3T3-E1细胞增殖,AFL层可抑制L929细胞的增殖;负载奥硝唑的复合膜可抑制牙龈卟啉单胞菌的增殖;多种复合膜均可诱导大鼠缺损颌骨进行重建,其中同时负载奥硝唑及n-HA的复合膜具有最优异的修复效果,且效果优于胶原口腔修复膜。结论以同时负载奥硝唑及n-HA的静电纺丝膜作为GBRL层的复合膜,具有优异的抑菌及诱导骨组织再生的作用,且效果优于临床常用胶原口腔修复膜,是一种极有潜力应用于诱导牙周疾病所致缺损骨再生的材料。

Objective This study aimed to prepare functional composite electrospinning fibrous membranes with the functions of antifibrosis and bacteriostasis,as well as to explore its repair effect on rat jaw defect.Methods Poly-(lactic acid-co-glycolic acid)fibrous membrane loaded with cyclic-arginine-glycine-aspartic acid sequence,ornidazole,and nanohydroxyapatite(n-HA)was prepared by electrospinning as the functional layer(GBRL)for adhering onto defective bone.A barrier layer with the function of supporting and isolating different functional layers was prepared by tape-casting method.Poly(p-dioxanone-co-l-phenylalanine)fiber membrane with the function of inhibiting fibrosis was prepared by electrospinning technology as the antifibrosis layer(AFL).The morphology of the composite membrane was characterized by scanning electron microscopy.The effects of different functional layers on the proliferation of mouse osteoblast precursor cells(MC3T3-E1)and mouse fibroblasts(L929)were studied by cell-proliferation test(CCK-8 method).The inhibitory effect of composite membrane on the proliferation of Porphyromonas gingivalis was studied by bacteriostatic circle test.A rat mandibular-bone defect model was established to study the repair effect of composite fiber membrane on bone-defect tissue.This repair effect was compared with that of collagen oral-repair membrane commonly used in clinics.Results The GBRL layer could support the proliferation of MC3T3-E1 cells,and the AFL layer could inhibit the proliferation of L929 cells.Composite membranes loaded with ornidazole could inhibit the proliferation of Porphyromonas gingivalis.Various composite membranes can induce the reconstruction of rat jaw defects,among which the composite membranes loaded with ornidazole and n-HA had the best repair effect,which was better than that of collagen oral-repair membrane.Conclusion The electrospun membrane loaded with ornidazole and n-HA as the composite fiber membrane of GBRL layer had excellent antibacterial and bone-tissue-regeneration activity.The effect was better than that of the commonly used collagen oral-repair membrane.Therefore,this material has great potential to induce bone regeneration for defects caused by periodontal diseases.