In vivo quercitrin anti-inflammatory effect involves release of quercetin, which inhibits inflammation through down-regulation of the NF-κB pathway
In vivo quercitrin anti-inflammatory effect involves release of quercetin, which inhibits inflammation through down-regulation of the NF-κB pathway
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DOI：
10.1002/eji.200425778
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发表时间：
2005-02-01
影响因子：
5.4
通讯作者：
Zarzuelo, A
中科院分区：
文献类型：
--
作者：
Comalada, M;Camuesco, D;Zarzuelo, A
槲皮素是蔬菜中常见的抗氧化剂黄酮类化合物，通常以糖基化形式存在，例如槲皮素（3-鼠李糖基槲皮素）。先前的体外实验表明，槲皮素在下调炎症反应方面比槲皮苷具有更大的作用。然而，这样的结果尚未在肠道炎症的体内实验模型中得到重现，其中槲皮素没有显示出有益作用，而其苷类槲皮素或芦丁则已证明其有效性。在这项研究中，我们报道了槲皮素在右旋糖酐硫酸钠诱导的大鼠结肠炎实验模型中的体内作用可以通过肠道微生物群裂解糖苷后产生的槲皮素的释放来介导。槲皮素（而非槲皮素）能够在体外下调骨髓源性巨噬细胞的炎症反应，这一事实支持了这一点。此外，我们还证明槲皮素通过抑制 NF-kappaB 通路来抑制细胞因子和诱导型一氧化氮合酶的表达，而不改变 c-Jun N 末端激酶活性（体外和体内）。总之，我们的报告表明槲皮素释放槲皮素以发挥其抗炎作用，该作用是通过抑制 NF-kappaB 通路介导的。
Quercetin is a common antioxidant flavonoid found in vegetables, which is usually present in glycosylated forms, such as quercitrin (3-rhamnosylquercetin). Previous in vitro experiments have shown that quercetin exerts a bigger effect than quercitrin in the down-regulation of the inflammatory response. However, such results have not been reproduced in in vivo experimental models of intestinal inflammation, in which quercetin did not show beneficial effects while its glycosides, quercitrin or rutin, have demonstrated their effectiveness. In this study, we have reported that the in vivo effects of quercitrin in the experimental model of rat colitis induced by dextran sulfate sodium can be mediated by the release of quercetin generated after glycoside's cleavage by the intestinal microbiota. This is supported by the fact that quercetin, but not quercitrin, is able to down-regulate the inflammatory response of bone marrow-derived macrophages in vitro. Moreover, we have demonstrated that quercetin inhibits cytokine and inducible nitric oxide synthase expression through inhibition of the NF-kappaB pathway without modification of c-Jun N-terminal kinase activity (both in vitro and in vivo). As a conclusion, our report suggests that quercitrin releases quercetin in order to perform its anti-inflammatory effect which is mediated through the inhibition of the NF-kappaB pathway.