Steroid sulfatase activity in leukocytes: a comparative study in 45,X; 46,Xi(Xq) and carriers of steroid sulfatase deficiency.
The enzyme steroid sulfatase (STS) hydrolyses 3-beta-hydroxysteroid sulfates. The female-male STS activity ratio is 1.04-1.7:1 in several cell lines in adults and reaches 2:1 in prepubertal subjects. In fibroblasts, STS values in X-chromosome abnormalities show a partial positive correlation according to the number of X-chromosomes. X-linked ichthyosis (XLI) carriers, with only one copy of the STS gene, present lower STS levels than normal controls. This study analyzes the STS activity in leukocytes of 46,Xi(Xq); 45,X; XLI carriers and normal controls using 7-[3H]-dehydroepiandrosterone sulfate as substrate. X-monosomy (1.07 +/- 0.18 pmol/mg protein/h), Xq isochromosome (1.02 +/- 0.12 pmol/mg protein/h) and normal females (1.03 +/- 0.11 pmol/mg protein/h) had similar STS values (p > 0.05). XLI-carriers and males showed the lowest STS levels (0.34 +/- 0.04 pmol/mg protein/h, p < 0.001 and 0.82 +/- 0.14 pmol/mg protein/h, p < 0.05, respectively). Female-male STS activity ratio in leukocytes was 1.3:1. These data indicate that a complex mechanism regulates the STS expression depending on each type of cell line.
Miranda-Duarte
A
A
Servicio de Genética, Hospital General de México, México D.F., Mexico.
Valdés-Flores
M
M
Miranda-Zamora
R
R
Díaz-Zagoya
J C
JC
Kofman-Alfaro
S H
SH
Cuevas-Covarrubias
S A
SA
D001192:Arylsulfatases / Q000097:blood* / Q000172:deficiency*; D002871:Chromosome Banding; D005260:Female; D006579:Heterozygote; D006801:Humans; D016114:Ichthyosis, X-Linked / Q000235:genetics*; D018404:Isochromosomes; D007962:Leukocytes / Q000201:enzymology*; D008297:Male; D009006:Monosomy; D012729:Sex Chromosome Aberrations / Q000201:enzymology*; D043266:Steryl-Sulfatase; D014960:X Chromosome
D001192:Arylsulfatases; D043266:Steryl-Sulfatase