Development of a new molecular therapeutic drug for brain pathology in lysosomal storage diseases

我们合成了一种新的半乳糖衍生物N-辛基-4-表-β-valienamine(NOEV)，用于人类神经遗传性疾病β-半乳糖苷中毒(G_&lt；M1&gt；-神经节苷脂中毒和Morquio B病)的新的分子治疗(化学伴侣疗法)。它的分子结构类似于半乳糖，分子量为287.40。它在室温下稳定，在水中的溶解度有限(最大可达5 mm)，但在甲醇或二甲基亚砜中可自由溶解。在体外，它是溶酶体(β-半乳糖苷酶)的一种强有力的竞争性抑制剂。IC_(50)为0.2μM。在细胞内低浓度培养的人或小鼠成纤维细胞中加入NOEV可恢复突变酶活性，导致细胞内底物储存量显著减少。我们收集了来自世界各地的50株β-半乳糖苷酶缺乏症成纤维细胞株，用于在培养系统中测试NOEV效应。在其中35%的人中观察到了超过3倍的增长。这种影响在引起幼年型神经节苷脂增多症的突变中最为明显，而对引起婴儿或成人G_&lt；M1&gt；-神经节苷脂增多症的突变效果较差。到目前为止，Morquio B细胞在该检测系统中没有明显的反应。我们已经建立了测定组织和血液中NOEV的方法，并开始了小鼠口服该化合物的实验。化学伴侣疗法可能对某些β-半乳糖体沉着症和其他可能有中枢神经系统受累的溶酶体储存性疾病患者有用。

We synthesized a novel galactose derivative, N-octyl-4-epi-β-valienamine(NOEV), for a new molecular therapy (chemical chaperone therapy) of a human neurogenetic disease, β-galactosidosis (G_<M1>-gangliosidosis and Morquio B disease). It has a molecular structure analogous to galactose ; molecular weight is 287.40. It is stable at room temperature, and has limited solubility in water (up to 5 mM), but freely soluble in methanol or dimethylsulfoxide. It is a potent competitive inhibitor of lysosomal (β-galactosidase in vitro. IC50 is 0.2 μM. Addition of NOEV in the culture medium restored mutant enzyme activity in cultured human or murine fibroblasts at low intracellular concentrations, resulting in a marked decrease of intracellular substrate storage. We collected 50 fibroblast strains from β-galactosidase deficiency disorders from all over the world, for testing the NOEV effect in the culture system. More than 3-fold increase was observed in 35% of them. The effect was most prominent in mutations causing juvenile G_<M1>-gangliosidosis, and less effective to those causing infantile or adult G_<M1>-gangliosidosis. So far Morquio B cells did not respond significantly in this assay system. We have established a method of NOEV determination in tissues and blood, and started mouse experiments by oral administration of this compound. Chemical chaperone therapy may be useful for certain patients with β-galactosidosis and potentially other lysosomal storage diseases with central nervous system involvement.