亚麻籽木脂素在大鼠体内的代谢研究

The Metabolism of Flaxseed Lignans in Rats

用对亚麻籽木脂素产生适应性反应的大鼠为单胃动物模型,借助反相高效液相色谱分析技术,通过2个试验对单胃动物胃肠道内植物木脂素向动物木脂素转化的主要场所,对木脂素类化合物的吸收代谢进程进行了研究。试验Ⅰ:以抗生素处理为对照,观察灌胃亚麻籽木脂素提取物后48 h内大鼠胃肠道食糜、粪便、血清中2种动物木脂素及亚麻籽木脂素含量的时间-浓度变化曲线。试验Ⅱ:经大鼠肝胆总管插管收集大鼠胆汁,观察胆汁中亚麻籽木脂素及2种动物木脂素浓度在灌胃后49 h内的动态变化。结果提示:抗生素可显著抑制动物木脂素的生成,推测动物木脂素主要的生成场所是微生物含量相对较多的结肠和盲肠,且动物木脂素的生成依赖于胃肠道微生物的存在。动物木脂素前体物质-亚麻籽木脂素能被吸收进入血液,且浓度高于同时间点动物木脂素的含量。在大鼠体内,亚麻籽木脂素及其2种代谢产物均存在肝肠循环。

The rats, which had been adapted to flaxseed lignan （secoisotariciresinol diglusoside, SDG） for 7 d, were used as a model for non-ruminant animals. Based on the reversed-phase high- performance liquid chromatography （RP-HPLC）, two experiments were conducted to study the main site of the transformation of SDG, the metabolism and absorption of lignans. Experiment Ⅰ ： After SDG infusion, the concentrations of SDG, enterodiol （END） and enterolactone （ENL） in the chyme of gastrointestinal tract （GIT）, feces and serum in rats with or without antibiotics were measured. Experiment Ⅱ ： After the bile was collected through cannula in hepatocholedchus, the levels of lignans were analyzed. The results showed that antibiotics can significantly inhibit the transformation of SDG, it may indicate that the colon and caecum, which contain more germs in GIT, produced the most mammalian lignans, and the formations of mammalian lignans depend on the flora in GIT. SDG could be absorbed into blood circulation and its content was higher than that of END and ENL. Once the SDG and mammalian lignans were absorbed, they might undergo enterohepatic circulation.