van de Kerkhof Esther G, de Graaf Inge A M, Ungell Anna-Lena B, Groothuis Geny M M
Department of Pharmacokinetics & Drug Delivery, Groningen Research Institute for Pharmacy, University of Groningen, Groningen, The Netherlands.
Drug Metab Dispos. 2008 Mar;36(3):604-13. doi: 10.1124/dmd.107.018820. Epub 2007 Dec 19.
Induction of drug enzyme activity in the intestine can strongly determine plasma levels of drugs. It is therefore important to predict drug-drug interactions in human intestine in vitro. We evaluated the applicability of human intestinal precision-cut slices for induction studies in vitro. Morphological examination and intracellular ATP levels indicated tissue integrity up to 24 h of incubation, whereas in proximal jejunum slices, the metabolic rate toward most substrates remained at 40 to 50% of initial values. In colon slices, the cytochrome P450 conversions were below the detection limit, but conjugation rates remained relatively constant during incubation. The inducibility of drug-metabolizing enzymes and P-glycoprotein was evaluated using prototypical inducers for five induction pathways. beta-Naphthoflavone (aryl hydrocarbon receptor ligand) induced CYP1A1 (132-fold in colon and 362-fold in proximal jejunum) and UDP glucuronosyltransferase (UGT) 1A6 mRNA (9.8-fold in colon and 3.2-fold in proximal jejunum). In proximal jejunum, rifampicin (RIF) [pregnane X receptor (PXR) ligand] induced CYP3A4 (5.2-fold), CYP2B6 (2-fold), UGT1A6 (2.2-fold), and multidrug resistance-1 (MDR1)/ABCB1 mRNA (2.7-fold), whereas 6beta-hydroxytestosterone formation (CYP3A4) increased 2-fold. In colon, RIF induced UGT1A6 32-fold and MDR1 2.2-fold. Dexamethasone (glucocorticoid receptor and PXR ligand) induced CYP3A4 mRNA (3.5-fold) and activity (5-fold) in proximal jejunum. Phenobarbital (constitutive androstane receptor activator) induced CYP3A4 (4.1-fold, only in jejunum), CYP2B6 (4.9-fold in colon and 2.3-fold in proximal jejunum), and MDR1/ABCB1 mRNA and CYP3A4 activity (2-fold only proximal jejunum). Quercetin (nuclear factor-E2-related factor 2 activator) induced UGT1A6 mRNA (6.7-fold in colon and 2.2-fold in proximal jejunum). In conclusion, this study shows that human intestinal precision-cut slices are useful to study induction of drug-metabolizing enzymes and transporters in the human intestine.
肠道中药物酶活性的诱导可强烈影响药物的血浆水平。因此，在体外预测人体肠道中的药物 - 药物相互作用非常重要。我们评估了人体肠道精密切片在体外诱导研究中的适用性。形态学检查和细胞内ATP水平表明，孵育长达24小时时组织保持完整，而在空肠近端切片中，对大多数底物的代谢率保持在初始值的40%至50%。在结肠切片中，细胞色素P450的转化率低于检测限，但孵育期间结合率保持相对恒定。使用针对五种诱导途径的典型诱导剂评估了药物代谢酶和P - 糖蛋白的诱导性。β-萘黄酮（芳烃受体配体）诱导CYP1A1（结肠中为132倍，空肠近端中为362倍）和UDP葡萄糖醛酸转移酶（UGT）1A6 mRNA（结肠中为9.8倍，空肠近端中为3.2倍）。在空肠近端，利福平（RIF）[孕烷X受体（PXR）配体]诱导CYP3A4（5.2倍）、CYP2B6（2倍）、UGT1A6（2.2倍）和多药耐药-1（MDR1）/ABCB1 mRNA（2.7倍），而6β-羟基睾酮形成（CYP3A4）增加2倍。在结肠中，RIF诱导UGT1A6 32倍和MDR1 2.2倍。地塞米松（糖皮质激素受体和PXR配体）在空肠近端诱导CYP3A4 mRNA（3.5倍）和活性（5倍）。苯巴比妥（组成型雄甾烷受体激活剂）诱导CYP3A4（4.1倍，仅在空肠中）、CYP2B6（结肠中为4.9倍，空肠近端中为2.3倍）以及MDR1/ABCB1 mRNA和CYP3A4活性（仅空肠近端中为两倍）。槲皮素（核因子E2相关因子2激活剂）诱导UGT1A6 mRNA（结肠中为6.7倍，空肠近端中为2.2倍）。总之，本研究表明人体肠道精密切片可用于研究人体肠道中药物代谢酶和转运蛋白的诱导作用。
