estrone-sulfate and Ichthyosis

We established a reversed phase high performance liquid chromatographic (HPLC) method of assaying lymphocyte steroid sulfatase activity using estrone sulfate as the substrate. Application of this method for diagnosis of 8 patients allowed us to clearly distinguish the patients from the normal controls. This method is simpler and less expensive than the method previously reported, since neither radioisotope labeled substrates nor radioisotope facilities are required. We consider it to be easily used and widely available in most clinical laboratories.

Topics: Adult; Arylsulfatases; Chromatography, High Pressure Liquid; Estrone; Female; Humans; Ichthyosis; Lymphocytes; Male; Reference Values; Sex Characteristics; Steryl-Sulfatase

Recessive X-linked ichthyosis (RXLI) has its biochemical basis in a defect of the enzyme steroid sulfatase. Since several studies have reported a simultaneous deficiency of arylsulfatase C and steroid sulfatase it has been hypothesized that both enzymes are identical. In human hair follicles, however, hydrolytic activity for 4-methylumbelliferone sulfate, the substrate for arylsulfatase C, is found, while dehydroepiandrosterone sulfate is not hydrolyzed at all. These findings suggested the possible existence of two different enzymes. In the present paper structure-activity studies and molecular energy calculations are used for the demonstration that the remaining sulfatase activity in hair follicles of RXLI patients can be explained on the basis of the assumption that the enzyme has not lost its total function but has become less efficient.

Topics: Adolescent; Adult; Dehydroepiandrosterone; Dehydroepiandrosterone Sulfate; Equilenin; Estrone; Female; Genetic Linkage; Hair; Humans; Hymecromone; Ichthyosis; Male; Middle Aged; Substrate Specificity; Sulfatases; X Chromosome

Steroid sulphatase (STS) activity was measured with tritiated dehydroepiandrosterone sulphate (DHEAS) and oestrone sulphate (OES) in leucocytes as well as in skin fibroblasts from 31 women who were presumed to be carriers of STS deficiency and recessive X-linked ichthyosis. Overall, 30 of the 31 women (96.8%) could be identified as heterozygotes in at least one of the four assay systems used, i.e. on the basis of having an STS activity below the 2.5 percentile calculated for normal control females. In the individual assay systems, the highest carrier detection rate was achieved with OES in leucocytes (96.2%), followed by DHEAS in leucocytes (80.8%), whereas a more pronounced overlap was present in the fibroblast systems. In leucocytes as well as in fibroblasts, the STS activity determined with DHEAS was positively correlated with the STS activity determined with OES (p less than 0.001) suggesting that a single sulphatase is responsible for the hydrolysis of both steroid sulphates.

Topics: Dehydroepiandrosterone; Dehydroepiandrosterone Sulfate; Estrone; Female; Fibroblasts; Genes, Recessive; Genetic Carrier Screening; Genetic Linkage; Humans; Ichthyosis; Leukocytes; Male; Steryl-Sulfatase; Sulfatases; X Chromosome