Anti-inflammatory mechanisms, pharmacokinetics of novel metabolites of vitamin E

描述（由申请人提供）：维生素E补充剂通常用作CAM（补充和替代医学）。维生素E的临床研究主要集中在1-生育酚（1 T）上，但在潜在的健康益处方面，结果令人失望。然而，我们和其他人已经证明，其他维生素E形式，特别是它们的新代谢产物具有1 T所不具备的独特抗炎特性。特别地，我们已经证明了13 '-羧基色原烷醇（4- 13'-COOH），一种衍生自4-生育酚（4 T）的长链代谢物，抑制环氧合酶（考克斯-1和考克斯-2）和5-脂氧合酶（5-LOX），其效力分别类似于布洛芬（一种常用的非甾体抗炎药- NSAID）和齐留通（一种临床使用的5-LOX抑制剂）。同时，3-生育酚（3 T）和4-生育酚（4 T）通过阻断钙离子内流，抑制考克斯-2介导的细胞内前列腺素E2的生成，抑制5-LOX介导的中性粒细胞内白三烯B4的生成，但1-生育酚无此作用。在初步研究中，我们发现4 T具有良好的抗关节炎作用。由于这些维生素E形式和代谢物抑制COX-和5-LOX-介导的促炎途径，我们认为这些化合物作为抗炎和抗关节炎剂可能上级于常用的NSAID，因为大多数NSAID仅抑制考克斯-催化的途径。此外，由于对COX和5-LOX的抑制作用更强，我们认为13 '-COOH可能比未代谢的维生素更有效。为了验证这些假设，我们将1）在基于细胞和酶的研究中研究长链羧基色原烷醇对考克斯-1/-2和5-LOX催化反应的作用和机制，2）开发用于维生素E代谢物的新的LC-MS-MS测定并表征4- 13 '-COOH、3 T和4 T的药代动力学，3）将体外观察到的4- 13 ′-COOH和维生素E形式的独特抗炎活性转化为大鼠炎症模型，并将其抗炎功效与已建立的NSAID进行比较，和4）通过在大鼠关节炎诱导的关节炎模型中研究4- 13 ′-COOH、3 T和4 T的抗关节炎功效，将抗炎作用转化为疾病相关模型。我们对这些维生素E形式及其新型代谢物的研究可能会发现一类新的抗炎药，其可能比一些常用的抗炎药更安全，但具有相似或上级疗效。拟议的研究将阐明抗炎作用的机制，并产生重要的临床前数据，这些数据是确保对这些化合物进行最大信息量的临床疗效研究所需的。 公共卫生相关性：本申请将测试特定维生素E形式及其新型代谢物长链羧基色原烷醇可能是有效的新型抗炎和抗关节炎剂的假设。这项研究可能导致发现治疗炎症性疾病的上级疗法优于常用的NSAID，因此可能导致在关节炎和疼痛管理中用维生素E代谢物替代NSAID或将其与NSAID组合，这是一个临床重要领域。

DESCRIPTION (provided by applicant): Vitamin E supplementation has been commonly used as a CAM (Complementary and Alternative Medicine). Clinical studies on vitamin E have focused exclusively on 1-tocopherol (1T), but they have yielded disappointing results regarding potential health benefits. However, we and others have shown that other vitamin E forms and especially their novel metabolites have unique anti-inflammatory properties that are not possessed by 1T. In particular, we have demonstrated that 13'-carboxychromanol (4-13'-COOH), a long-chain metabolite derived from 4- tocopherol (4T), inhibits cyclooxygenases (COX-1 and COX-2) and 5-lipoxygenase (5-LOX) with potency similar to ibuprofen (a commonly used non-steroid anti-inflammatory drugs - NSAID) and zileuton (a clinically used 5-LOX inhibitor), respectively. Meanwhile, 3-tocopherol (3T) and 4T, but not 1T, inhibited COX-2-mediated prostaglandin E2 generation in cells and suppressed 5-LOX-mediated leukotriene B4 production in neutrophils by blocking calcium influx. In a preliminary study, we have found that 4T exhibited promising anti-arthritis effects. Since these vitamin E forms and metabolites inhibit both COXs- and 5-LOX-mediated pro-inflammatory pathways, we propose that these compounds may be superior to commonly used NSAIDs as anti-inflammatory and anti-arthritis agents because most NSAIDs only inhibit COX- catalyzed pathway. In addition, due to stronger inhibition of COXs and 5-LOX, we propose that 13'-COOH may be more effective than un-metabolized vitamins. To test these hypotheses, we will 1) investigate the effect and mechanism of long-chain carboxychromanols on COX-1/-2 and 5-LOX-catalyzed reactions in cell- and enzyme-based studies, 2) develop a new LC-MS-MS assay for vitamin E metabolites and characterize the pharmacokinetics of 4-13'-COOH, 3T and 4T, 3) translate the unique anti-inflammatory activity of 4-13'-COOH and vitamin E forms observed in vitro to a rat inflammation model and compare their anti-inflammatory efficacy to established NSAIDs, and 4) translate the anti-inflammatory actions to a disease relevant model by investigating anti-arthritis efficacy of 4-13'-COOH, 3T and 4T in the rat adjuvant-induced arthritis model. Our studies on these vitamin E forms and their novel metabolites may lead to discovery of a new class of anti-inflammatory agents that may be safer than some commonly used anti-inflammatory drugs and yet have similar or superior efficacy. The proposed studies will elucidate mechanisms of anti-inflammatory action and generate important preclinical data that are needed to insure maximally informative clinical efficacy studies on these compounds. PUBLIC HEALTH RELEVANCE: This application will test the hypothesis that specific vitamin E forms and their novel metabolites, long-chain carboxychromanols, may be effective novel anti-inflammatory and anti-arthritis agents. This study may lead to discovery of superior therapy for treatment of inflammatory diseases over commonly used NSAIDs and therefore may result in NSAID replacement with vitamin E metabolites or their combination with NSAIDs in arthritis and pain management, a clinically important area.