Bioactive Polymeric Nanoparticles for Periodontal Therapy

Aimsto design calcium and zinc-loaded bioactive and cytocompatible nanoparticles for the treatment of periodontal disease.MethodsPolymP-nActive nanoparticles were zinc or calcium loaded. Biomimetic calcium phosphate precipitation on polymeric particles was assessed after 7 days immersion in simulated body fluid, by scanning electron microscopy attached to an energy dispersive analysis system. Amorphous mineral deposition was probed by X-ray diffraction. Cell viability analysis was performed using oral mucosa fibroblasts by: 1) quantifying the liberated deoxyribonucleic acid from dead cells, 2) detecting the amount of lactate dehydrogenase enzyme released by cells with damaged membranes, and 3) by examining the cytoplasmic esterase function and cell membranes integrity with a fluorescence-based method using the Live/Dead commercial kit. Data were analyzed by Kruskal-Wallis and Mann-Whitney tests.ResultsPrecipitation of calcium and phosphate on the nanoparticles surfaces was observed in calcium-loaded nanoparticles. Non-loaded nanoparticles were found to be non-toxic in all the assays, calcium and zinc-loaded particles presented a dose dependent but very low cytotoxic effect.ConclusionsThe ability of calcium-loaded nanoparticles to promote precipitation of calcium phosphate deposits, together with their observed non-toxicity may offer new strategies for periodontal disease treatment.本研究旨在设计负载钙与锌的生物活性且细胞相容性良好的纳米颗粒，用于牙周疾病的治疗。方法：将PolymP-nActive纳米颗粒负载锌或钙。将其置于模拟体液中浸泡7天后，通过搭载能量色散分析系统的扫描电子显微镜，评估聚合物颗粒表面的仿生磷酸钙沉积情况；通过X射线衍射表征无定形矿物沉积情况。采用口腔黏膜成纤维细胞开展细胞活力分析，具体包括：1）定量死细胞释放的脱氧核糖核酸（deoxyribonucleic acid）；2）检测细胞膜受损细胞释放的乳酸脱氢酶含量；3）使用商用Live/Dead荧光试剂盒，通过荧光法检测细胞质酯酶功能与细胞膜完整性。数据采用克鲁斯卡尔-沃利斯检验与曼-惠特尼检验进行统计分析。结果：负载钙的纳米颗粒表面可观察到钙与磷酸盐的沉积。未负载的纳米颗粒在所有实验中均无毒性；负载钙与锌的颗粒呈现出剂量依赖性但极低的细胞毒性效应。结论：负载钙的纳米颗粒可促进磷酸钙沉积物沉积，加之其良好的生物相容性，可为牙周疾病的治疗提供全新策略。