Lefebvre Tania, Foster Brian C, Drouin Cathy E, Krantis Anthony, Livesey John F, Jordan Scott A
Office of Science, Therapeutic Products Directorate, Health Canada, Ottawa, Ontario, Canada.
J Pharm Pharm Sci. 2004 Aug 12;7(2):265-73.
Valerian root ( Valeriana officinalis L.) has been used since antiquity as a medicinal herb. Recent studies have found that certain herbal products used concomitantly with conventional therapeutic products can markedly affect drug disposition.
The in vitro effect of aliquots from 14 commercially available single-entity and blended products containing valerian root on cytochrome P450 CYP3A4-mediated metabolism and P-glycoprotein transport has been determined with aqueous, ethanol and acetonitrile extracts.
Hydroxyvalerenic acid, acetoxyvalerenic acid and valerenic acid content was analyzed and wide variation was found between samples and compared to the concentrations noted on the product labels. Valerian extracts from the products tested also exhibited a marked capacity to inhibit cytochrome P450 3A4-mediated metabolism and P-glycoprotein transport based upon the ATPase assay.
There is wide variation between commercially available samples of valerian root. The findings from this study suggest that valerian root may have an initial inhibitory effect when taken with therapeutic products. Further work is warranted to determine whether valerian root can affect other CYP450 isozymes and how the results of this in vitro investigation can be extrapolated to in vivo situations.
缬草根（缬草）自古以来就被用作草药。最近的研究发现，某些草药产品与传统治疗产品同时使用时，可显著影响药物代谢。
用含有缬草根的14种市售单一成分和混合产品的等分试样的水提取物、乙醇提取物和乙腈提取物，测定其对细胞色素P450 CYP3A4介导的代谢和P-糖蛋白转运的体外作用。
分析了羟基缬草烯酸、乙酰氧基缬草烯酸和缬草烯酸的含量，发现样品之间存在很大差异，并与产品标签上标注的浓度进行了比较。根据ATP酶分析，受试产品的缬草提取物也表现出显著抑制细胞色素P450 3A4介导的代谢和P-糖蛋白转运的能力。
市售缬草根样品之间存在很大差异。本研究结果表明，缬草根与治疗产品同时服用时可能具有初始抑制作用。有必要进一步开展研究，以确定缬草根是否会影响其他CYP450同工酶，以及如何将该体外研究结果外推至体内情况。
