Mochizuki S, Mizukami H, Ogura T, Kure S, Ichinohe A, Kojima K, Matsubara Y, Kobayahi E, Okada T, Hoshika A, Ozawa K, Kume A
Division of Genetic Therapeutics, Center for Molecular Medicine, Jichi Medical School, Tochigi, Japan.
Gene Ther. 2004 Jul;11(13):1081-6. doi: 10.1038/sj.gt.3302262.
Classical phenylketonuria (PKU) is a metabolic disorder caused by a deficiency of the hepatic enzyme phenylalanine hydroxylase (PAH). If untreated, accumulation of phenylalanine will damage the developing brain of affected individuals, leading to severe mental retardation. Here, we show that a liver-directed PAH gene transfer brought about long-term correction of hyperphenylalaninemia and behavioral improvement in a mouse model of PKU. A recombinant adeno-associated virus (AAV) vector carrying the murine PAH cDNA was constructed and administered to PAH-deficient mice (strain PAH(enu2)) via the portal vein. Within 2 weeks of treatment, the hyperphenylalaninemic phenotype improved and completely normalized in the animals treated with higher vector doses. The therapeutic effect persisted for 40 weeks in male mice, while serum phenylalanine concentrations in female animals gradually returned to pretreatment levels. Notably, this long-term correction of hyperphenylalaninemia was associated with a reversal of hypoactivity observed in PAH(enu2) mice. While locomotory activity over 24 h and exploratory behavior were significantly decreased in untreated PAH(enu2) mice compared with the age-matched controls, these indices were completely normalized in 12-month-old male PKU mice with lowered serum phenylalanine. These results demonstrate that AAV-mediated liver transduction ameliorated the PKU phenotype, including central nervous system dysfunctions.
经典型苯丙酮尿症（PKU）是一种由肝脏酶苯丙氨酸羟化酶（PAH）缺乏引起的代谢紊乱疾病。如果不进行治疗，苯丙氨酸的积累会损害受影响个体正在发育的大脑，导致严重智力迟钝。在此，我们表明在PKU小鼠模型中，肝脏靶向的PAH基因转移实现了高苯丙氨酸血症的长期纠正和行为改善。构建了携带小鼠PAH cDNA的重组腺相关病毒（AAV）载体，并通过门静脉将其给予PAH缺陷小鼠（PAH(enu2)品系）。在治疗的2周内，高苯丙氨酸血症表型得到改善，并且在接受较高载体剂量治疗的动物中完全恢复正常。治疗效果在雄性小鼠中持续了40周，而雌性动物的血清苯丙氨酸浓度逐渐恢复到治疗前水平。值得注意的是，这种高苯丙氨酸血症的长期纠正与在PAH(enu2)小鼠中观察到的活动减退的逆转有关。与年龄匹配的对照相比，未经治疗的PAH(enu2)小鼠24小时的运动活动和探索行为显著降低，而在血清苯丙氨酸降低的12月龄雄性PKU小鼠中，这些指标完全恢复正常。这些结果表明，AAV介导的肝脏转导改善了PKU表型，包括中枢神经系统功能障碍。
