研發生物可降解性奈米顆粒控制四環黴素和洛伐他汀之釋放以應用於牙周病治療

Abstract

牙周疾病是影響牙齒支持組織的發炎性疾病，由細菌感染相鄰牙齒的組織所引起的。牙周病會破壞牙齒周圍組織，減少牙齒周圍的支撐結構，最後導致牙齒的脫落，牙周病的治療從控制發炎及感染，擴展至再生治療的應用，進而恢復牙齒周遭的健康牙周組織。 本研究主要以可被生物降解性之聚乳酸-甘醇酸（PLGA）共聚物與幾丁聚醣（Chitosan）為材料，製備出可被生物降解的藥物，由聚乳酸聚甘醇酸混合幾丁聚醣當載體，控制洛伐他汀和四環黴素的釋放，以用來作為治療牙周病藥物的潛在應用。四環黴素會先釋放以抑制細菌生長，接著洛伐他汀再釋放以增加骨再生。在奈米顆粒的尺寸、組成以及結構性質分析上，我們使用了穿透式電子顯微鏡（TEM）、動態光散射粒徑分析儀（DLS）、紅外線光譜儀（FT-IR）來做測試。接下來，我們藉由最小抑制濃度和抑菌環比較藥物抗牙周病厭氧菌的效果。使用人類胚胎上顎間質細胞（HEPM）做生物相容性測試，以及鹼性磷酸酶試驗。實驗結果顯示，本研究中所製備出的0.3%濃度四環黴素的PLGA-chitosan-lovastatin-tetracycline藥物，其抑菌效果高於最小抑菌濃度，且其釋出的藥劑對於牙周病原菌A. actinomycemcomitans 和 P. nigrescens有抑菌效果，並且具有生物相容性，對細胞的活性不會產生影響，以及可以促進骨分化指標細胞鹼性磷酸酶(ALPase)的表現。

Periodontal disease can cause destruction of periodontal tissue, reduce periodontal supporting structure, and finally lead to tooth loss. The development of periodontal therapy starts from infection control to tissue regeneration in order to regenerate the healthy tissue surrounding tooth structure. This study used poly lactied-co-glycolic acid (PLGA) and chitosan to prepare the biodegradable PLGA-chitosan nanoparticles for controlled release of tetracycline and lovastatin as adjunctive treatment of periodontitis. Tetracycline has been proved to inhibit bacterial growth and lovastatin is able to induce bone regeneration. The particle size, morphology, and chemical stucture of the obtained nanoparticles were determined by transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier transform -infrared spectroscopy (FT-IR), respectively. Subsequently, the ability of the drug to inhibit the periodontal pathogens including A. actinomycemcomitans and P nigrescens was investigated by minimal inhibition concentration (MIC) and cup-plate method. Cell proliferation was examined by MTT assay. Cell differentiation and mineralization were evaluated by alkaline phosphatase activity quantitative assay. The results demonstrated that the PLGA-chitosan-lovastatin-tetracycline (0.3%) was the optimal concentration and showed a sustained release profile to inhibit the growth of periodontal pathogens. PLGA-chitosan-lovastatin-tetracycline (0.3%) is also biocompatible by the MTT assay and the ALPase activity in HEPM cells could be significantly stimulated by lovastatin carried in PLGA-chitosan-lovastatin-tetracycline (0.3%) nanoparticles.