Department of Chemistry, Tshwane University of Technology, Pretoria, South Africa.
Planta Med. 2012 Feb;78(3):260-8. doi: 10.1055/s-0031-1280367. Epub 2011 Nov 21.
Sceletium tortuosum is an indigenous South African plant that has traditionally been used for its mood-enhancing properties. Recently, products containing S. tortuosum have become increasingly popular and are commonly administered as tablets, capsules, teas, decoctions, or tinctures, while traditionally the dried plant material has been masticated. This study evaluated the in vitro permeability of the four major S. tortuosum alkaloids (i.e., mesembrine, mesembrenone, mesembrenol, and mesembranol) across porcine intestinal, sublingual, and buccal tissues in their pure form and in the form of three different crude plant extracts, namely water, methanol, and an acid-base alkaloid-enriched extract. The permeability of mesembrine across intestinal tissue was higher than that of the highly permeable reference compound caffeine (which served as a positive control for membrane permeability) both in its pure form, as well as in the form of crude extracts. The intestinal permeability of mesembranol was similar to that of caffeine, while those of mesembrenol and mesembrenone were lower than that of caffeine, but much higher than that of the poorly permeable reference compound atenolol (which served as a negative control for membrane permeability). In general, the permeabilities of the alkaloids were lower across the sublingual and the buccal tissues than across the intestinal tissue. However, comparing the transport of the alkaloids with that of the reference compounds, there are indications that transport across the membranes of the oral cavity may contribute considerably to the overall bioavailability of the alkaloids, depending on pre-systemic metabolism, when the plant material is chewed and kept in the mouth for prolonged periods. The results from this study confirmed the ability of the alkaloids of S. tortuosum in purified or crude extract form to permeate across intestinal, buccal, and sublingual mucosal tissues.
美斯卡灵是一种原产于南非的植物，传统上被用于改善情绪。最近，含有美斯卡灵的产品越来越受欢迎，通常以片剂、胶囊、茶、煎剂或酊剂的形式给药，而传统上则咀嚼干燥的植物材料。本研究评估了四种主要的美斯卡灵生物碱（即美西律、美西滨、美西醇和美西醇）在其纯形式和三种不同粗提物（即水、甲醇和酸碱生物碱富集提取物）形式下穿过猪肠、舌下和颊黏膜的体外渗透性。美西律穿过肠组织的渗透性高于高度可渗透的参考化合物咖啡因（作为膜渗透性的阳性对照），无论是在其纯形式还是在粗提物形式下。美西醇的肠渗透性与咖啡因相似，而美西滨和美西滨的肠渗透性低于咖啡因，但远高于渗透性差的参考化合物阿替洛尔（作为膜渗透性的阴性对照）。一般来说，生物碱在舌下和颊黏膜中的渗透性低于肠组织。然而，将生物碱的转运与参考化合物进行比较，有迹象表明，当咀嚼植物材料并长时间保留在口腔中时，口腔膜的转运可能对生物碱的整体生物利用度有很大贡献，这取决于预系统代谢。本研究的结果证实了美斯卡灵生物碱在纯化或粗提物形式下穿过肠、颊和舌下黏膜组织的能力。
