Polymeric nanoparticles have been widely investigated as insulin delivery systems for oral administration. However, the toxic nature of many artificial polymers hampers their effective application, creating a demand for the further exploration of alternative natural polymers. In addition, ethnobotanical research has reported that over 800 plant species have a hypoglycemic function, some of which are polymers. For the advantages of both areas to be combined, the aim of this work was to choose an organic hypoglycemic polymer and prepare it into an insulin carrier to build a dual-functional oral insulin delivery system. We found that the insulin loading rate, release mode, thermostability, and both in vitro and in vivo absorption and efficacy varied with the different modifications of polygalacturonic acid (PGLA) nanoparticulate backbones. By in vivo pharmaceutical testing and constantly monitoring the symptoms of type 1 diabetic (T1D) rats, we ascertained the hypoglycemic function of the nanoparticles and showed that overall diabetic symptoms were ameliorated after the long-term daily administration of nanoparticles with no significant damage to organ structure or cell viability.

中文翻译：

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口服胰岛素降血糖纳米颗粒的制备与表征

高分子纳米颗粒已被广泛研究为口服给药的胰岛素递送系统。然而，许多人造聚合物的毒性本质阻碍了它们的有效应用，从而产生了对进一步探索替代天然聚合物的需求。此外，民族植物学研究报告称，有800多种植物具有降血糖功能，其中一些是聚合物。为了将这两个领域结合起来的优势，这项工作的目的是选择一种有机降血糖聚合物并将其制备为胰岛素载体，以构建一种双重功能的口服胰岛素递送系统。我们发现，随着聚半乳糖醛酸（PGLA）纳米颗粒骨架的不同修饰，胰岛素的负载率，释放模式，热稳定性以及体内外吸收和功效均发生变化。