School of Pharmacy, The University of Nottingham, University Park, Nottingham NG7 2RD, UK.
Department of Inorganic Chemistry, Jagiellonian University in Krakόw, Faculty of Chemistry, Gronostajowa St. 2, 30-387 Krakόw, Poland.
J Pharm Sci. 2019 Jul;108(7):2438-2446. doi: 10.1016/j.xphs.2019.02.025. Epub 2019 Mar 6.
Some forms of bovine lactoferrin (bLf) are effective in delaying Clostridioides difficile growth and preventing toxin production. However, therapeutic use of bLf may be limited by protein stability issues. The objective of this study was to prepare and evaluate colon-targeted, pH-triggered alginate microparticles loaded with bioactive bLf and to evaluate their anti-C difficile defense properties in vitro. Different forms of metal-bound bLf were encapsulated in alginate microparticles using an emulsification or internal gelation method. The microparticles were coated with chitosan to control protein release. In vitro drug release studies were conducted in pH-simulated gastrointestinal conditions to investigate the release kinetics of encapsulated protein. No significant release of metal-bound bLf was observed at acidic pH; however, on reaching simulated colonic pH, most of the encapsulated lactoferrin was released. The application of bLf (5 mg/mL) delivered from alginate microparticles to human intestinal epithelial cells significantly reduced the cytotoxic effects of toxins A and B as well as bacterial supernatant on Caco-2 and Vero cells, respectively. These results are the first to suggest that alginate-bLf microparticles show protective effects against C difficile toxin-mediated epithelial damage and impairment of barrier function in human intestinal epithelial cells. The future potential of lactoferrin-loaded alginate microparticles against C difficile deserves further study.
一些形式的牛乳铁蛋白（bLf）可有效延缓艰难梭菌的生长并防止毒素产生。然而，bLf 的治疗用途可能受到蛋白质稳定性问题的限制。本研究旨在制备和评估载有生物活性 bLf 的、具有结肠靶向性和 pH 触发特性的海藻酸钠微球，并评估其在体外的抗艰难梭菌防御特性。使用乳化或内凝胶化方法将不同形式的金属结合 bLf 包封在海藻酸钠微球中。用壳聚糖对微球进行涂层以控制蛋白质释放。在 pH 模拟胃肠道条件下进行了体外药物释放研究，以研究包封蛋白的释放动力学。在酸性 pH 下未观察到金属结合 bLf 的明显释放；然而，当达到模拟结肠 pH 时，大部分包封的乳铁蛋白被释放。从海藻酸钠微球中释放的 bLf（5 mg/mL）的应用显著降低了毒素 A 和 B 以及细菌上清液对 Caco-2 和 Vero 细胞的细胞毒性作用。这些结果首次表明，海藻酸钠-bLf 微球对艰难梭菌毒素介导的上皮损伤和人肠上皮细胞屏障功能障碍具有保护作用。负载乳铁蛋白的海藻酸钠微球对艰难梭菌的未来潜力值得进一步研究。
