巴豆不同炮制品肠道毒性差异及炮制对巴豆脂肪油、总蛋白的影响

Intestinal toxicity of different processed products of Crotonis Fructus and effect of processing on fatty oil and total protein

为考察不同巴豆制霜过程对巴豆脂肪油、总蛋白及致肠道毒性的影响,将巴豆生品进行热压去油,冷压去油和淀粉稀释法炮制,得3种巴豆制霜品。小鼠灌胃给药,采用ELISA法测定小鼠血清中二胺氧化酶(DAO)和D-乳酸含量,考察肠道通透性的变化;采用Western blot法测定不同肠段中紧密连接蛋白(occludin,claudin-1)表达变化,考察巴豆生品及其制霜品对肠道损伤的毒性差异。分别采用GC-MS和SDS-PAGE分析巴豆制霜前后脂肪油和总蛋白的变化。结果显示,巴豆生品能够显著增加小鼠肠道通透性和降低十二指肠、空肠紧密连接蛋白表达。制霜后小鼠肠道通透性和紧密连接蛋白表达均趋向正常,毒性降低。不同巴豆霜肠道毒性大小为:冷压巴豆霜>稀释巴豆霜≈热压巴豆霜。3种巴豆霜脂肪油成分组成一致,但总蛋白含量和组成具有明显差异。含量高低:冷压巴豆霜>热压巴豆霜>稀释巴豆霜,其中冷压和稀释巴豆霜总蛋白条带相对分子质量分布一致,热压巴豆霜总蛋白组成发生显著变化,条带减少,变淡。表明在巴豆制霜中,稀释和加热过程均能够降低蛋白含量,且加热导致部分蛋白变性失活。稀释和加热均能降低巴豆霜毒性,但加热过程减毒作用更显著,表明加热是巴豆制霜过程中的关键步骤。

To study the effect of different processes of Crotonis Fructus on fatty oil, total protein and intestinal toxicity, three kinds of processed products(heat Crotonis Semen Pulveratum, non-heat Crotonis Semen Pulveratum and diluted Crotonis Semen Pulveratum) were prepared. Mice were orally given Crotonis Fructus. The content of DAO and D-lactic acid in the serum were measured by ELISA to investigate the change of intestinal permeability in mice. Western blot was used to determine the expressions of tight junction proteins(occludin, claudin-1) in different intestinal tract, so as to observe the effect of Crotonis Fructus and its processed products on intestinal epithelial barrier. These results showed that Crotonis Fructus could significantly increase the intestinal permeability and reduce the expression of tight junction proteins in duodenum and jejunum, but with little impact on the ileum and colon. The intestinal permeability and the expression of tight junction proteins became normal after processing. However, the order of the toxicity of Crotonis Semen Pulveratum from high to low was non-heat Crotonis Semen Pulveratum > diluted Crotonis Semen Pulveratum ≈ heat Crotonis Semen Pulveratum. According to the results of composition, the composition of fatty oil did not change during the processing, but the content and composition of total protein in Crotonis Semen Pulveratum changed significantly. The order of total protein content from high to low was that non-heat Crotonis Semen Pulveratum > heat Crotonis Semen Pulveratum > diluted Crotonis Semen Pulveratum. The molecular weight distribution of the total protein bands of non-heat Crotonis Semen Pulveratum and diluted Crotonis Semen Pulveratum was consistent, but the composition of total protein of heat Crotonis Semen Pulveratum significantly changed as evidenced by decreased and thin some stripes. This indicated that heating and dilution could reduce the content of total protein, and heating could cause partial protein denaturation and inactivation. In conclusion, both dilution and heating can reduce the toxicity of Crotonis Fructus, but the heating shows a more significant attenuation effect, indicating that heating is the key step in Crotonis Semen Pulveratum preparation.