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-epi-β-valienamine(NOEV)，用于治疗人类神经遗传性疾病β-半乳糖病（G_<M1>-神经节脂质病和Morquio B病）的新分子疗法（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（可达5毫米），但可自由溶于甲醇或二甲基亚砜。它是一种有效的体外溶酶体（β-半乳糖苷酶）竞争性抑制剂。IC50为0.2 μM。在培养基中添加NOEV可以恢复培养的人或鼠成纤维细胞在低细胞内浓度下的突变酶活性，导致细胞内底物储存显著减少。我们收集了50株来自世界各地的β-半乳糖苷酶缺乏症成纤维细胞，用于测试NOEV在培养系统中的效果。其中有35%的人增加了3倍以上。这种作用在引起少年G_<M1>-神经节脂质病的突变中最为突出，而对引起婴儿或成人G_<M1>-神经节脂质病的突变效果较差。到目前为止，Morquio B细胞在这个实验系统中没有明显的反应。我们建立了组织和血液中NOEV的测定方法，并通过口服该化合物进行了小鼠实验。化学伴侣疗法可能对某些β-半乳糖糖苷病和其他可能累及中枢神经系统的溶酶体积存病的患者有用。

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.