Dioscorins, the major storage proteins of yam tubers, exert immunomodulatory activities. To improve oral bioavailability of dioscorins in the intestine, recombinant dioscorin (rDioscorin) was coated with N,N,N-trimethyl chitosan (TMC) and tripolyphosphate (TPP), resulting in the formation of TMC-rDio-TPP nanoparticles (NPs). The loading capacity and entrapment efficiency of rDioscorin in the NPs were 26 ± 0.7% and 61 ± 1.4%, respectively. The NPs demonstrated a substantial release profile in the pH environment of the jejunum. The rDioscorin released from the NPs stimulated proliferation and phagocytosis of the macrophage RAW264.7 and activated the gene expression of IL-1β and IL-6. Incubation of the NPs in the Caco-2 cell monolayer led to a 5.2-fold increase of P_app compared with rDioscorin alone, suggesting that rDioscorin, with the assistance of TMC, can be promptly transported across the intestinal epithelia. These results demonstrate that the TMC-rDio-TPP NPs can be utilized for elucidating the immunopharmacological effects of dioscorins through oral delivery.

中文翻译：

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跨山细胞跨人肠道Caco-2细胞单层运输山药Dioscorin加载纳米粒子的发展。

薯tube是薯类块茎的主要贮藏蛋白，具有免疫调节活性。为了提高薯di皂素在肠中的口服生物利用度，将重组地高辛（rDioscorin）涂以N，N，N-三甲基壳聚糖（TMC）和三聚磷酸盐（TPP），导致形成TMC-rDio-TPP纳米粒子（NPs）。NP中rDioscorin的负载量和包封率分别为26±0.7％和61±1.4％。NPs在空肠的pH环境中显示出实质性的释放曲线。从NP释放的rDioscorin刺激巨噬细胞RAW264.7的增殖和吞噬并激活IL-1β和IL-6的基因表达。Caco-2细胞单层中NP的孵育导致P _app增加5.2倍与单独使用rDioscorin相比，这表明rDioscorin在TMC的辅助下可以迅速转运到整个肠上皮。这些结果表明，TMC-rDio-TPP NPs可用于阐明口服口服薯di提取物的免疫药理作用。