The Ratner Chair in Chemistry, Casali Institute of Applied Chemistry, The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem 9190401, Israel.
Skin Research Institute, Dead-Sea & Arava Science Center, Ein Gedi, Israel.
Colloids Surf B Biointerfaces. 2018 Jan 1;161:670-676. doi: 10.1016/j.colsurfb.2017.11.031. Epub 2017 Nov 12.
In the present study we aimed to control insulin release from the reverse hexagonal (H) mesophase using Thermomyces lanuginosa lipase (TLL) in the environment (outer TLL) or within the H cylinders (inner TLL). Two insulin-loaded systems differing by the presence (or absence) of phosphatidylcholine (PC) were examined. In general, incorporation of PC into the H interface (without TLL) increased insulin release, as a more cooperative system was formed. Addition of TLL to the systems' environments resulted in lipolysis of the H structure. In the absence of PC, the lipolysis was more dominant and led to a significant increase in insulin release (50% after 8h). However, the presence of PC stabilized the interface, hindering the lipolysis, and therefore no impact on the release profile was detected during the first 8h. Entrapment of TLL within the H cylinders (with and without PC) drastically increased insulin release in both systems up to 100%. In the presence of PC insulin released faster and the structure was more stable. Consequently, the presence of lipases (inner or outer) both enhanced the destruction of the carrier, and provided sustained release of the entrapped insulin.
在本研究中，我们旨在通过Thermomyces lanuginosa 脂肪酶（TLL）在环境（外 TLL）或 H 柱内（内 TLL）控制反六方（H）中间相的胰岛素释放。检查了两种通过存在（或不存在）磷脂酰胆碱（PC）而有所不同的胰岛素负载系统。一般来说，将 PC 掺入 H 界面（无 TLL）会增加胰岛素释放，因为形成了更具协同性的系统。向系统环境中添加 TLL 会导致 H 结构的脂解。在没有 PC 的情况下，脂解更为占主导地位，导致胰岛素释放显著增加（8 小时后增加 50%）。然而，PC 的存在稳定了界面，阻碍了脂解，因此在最初的 8 小时内没有检测到释放曲线的变化。TLL 被包埋在 H 柱内（有或没有 PC）会在两种系统中使胰岛素释放增加高达 100%。在 PC 存在的情况下，胰岛素释放更快，结构更稳定。因此，脂肪酶（内部或外部）的存在都增强了载体的破坏，并提供了包封胰岛素的持续释放。
