Molzer B, Sundt-Heller R, Kainz-Korschinsky M, Zobel M
Division of Neurochemistry, University of Vienna, Austria.
Am J Med Genet. 1992 Nov 1;44(4):523-6. doi: 10.1002/ajmg.1320440429.
Sulfatide excretion in urine and arylsulfatase A (ASA) activity in leukocytes were determined in 10 homozygotes of metachromatic leukodystrophy (MLD), 7 obligate and 5 facultative MLD heterozygotes, 6 low ASA subjects (not related to MLD homozygotes), and in 9 controls. As compared to controls (sulfatides: 0-2 nmol/mg lipid; ASA: 101-287 nmol p-nitrocatechol/mg protein/hr), MLD homozygotes displayed highly increased sulfatide excretions (27-280 nmol) and low residual ASA activities (0-13 nmol). Of 12 MLD heterozygotes (ASA: 18-87 nmol) 10 showed increased sulfatides (3-24 nmol). All heterozygotes with ASA activity < 60 nmol (n = 8) had elevated sulfatide excretions (4-24 nmol). Thus, reduction of ASA activity below 40% of the mean value of controls seems to be the critical threshold for elevated sulfatide excretion in MLD heterozygotes. The low ASA subjects (ASA in the heterozygote range) excreted sulfatides in the control range, even those with ASA activities < 60 nmoles (n = 3; including a definite homozygote for ASA-pseudodeficiency; ASA:25 nmol). Statistical evaluation of sulfatide excretion and ASA activity in all subjects (n = 37) revealed a significant inverse relation (Spearman rank correlation; R = 0.8278, P < 0.001). The finding of elevated sulfatide excretion in certain MLD heterozygotes might point to increase of sulfatides also in the nervous system.
对10例异染性脑白质营养不良（MLD）纯合子、7例肯定的和5例可能的MLD杂合子、6例低芳基硫酸酯酶A（ASA）受试者（与MLD纯合子无关）以及9例对照者测定了尿中硫脂排泄量和白细胞中芳基硫酸酯酶A（ASA）活性。与对照组（硫脂：0 - 2 nmol/ mg脂质；ASA：101 - 287 nmol对硝基邻苯二酚/ mg蛋白质/小时）相比，MLD纯合子的硫脂排泄量显著增加（27 - 280 nmol），而残余ASA活性较低（0 - 13 nmol）。在12例MLD杂合子（ASA：18 - 87 nmol）中，10例的硫脂增加（3 - 24 nmol）。所有ASA活性< 60 nmol的杂合子（n = 8）硫脂排泄量均升高（4 - 24 nmol）。因此，MLD杂合子中ASA活性降至对照组平均值的40%以下似乎是硫脂排泄增加的临界阈值。低ASA受试者（ASA在杂合子范围内）的硫脂排泄量在对照范围内，即使是那些ASA活性< 60 nmol的受试者（n = 3；包括1例明确的ASA假缺陷纯合子；ASA：25 nmol）。对所有受试者（n = 37）的硫脂排泄量和ASA活性进行统计学评估，发现两者呈显著负相关（Spearman等级相关；R = 0.8278，P < 0.001）。在某些MLD杂合子中发现硫脂排泄增加，这可能表明神经系统中的硫脂也有所增加。
