In this article, we describe a 46-year-old man with severe high-density lipoprotein (HDL) deficiency and his kindred. In the proband, HDL cholesterol and apolipoprotein (apo) A-I levels were 5 and 4.5 mg/dL, respectively. Xanthomata, xanthelasma, arcus corneae, and hepatosplenomegaly were not present The proband had coronary artery disease, but it was impossible to state whether the HDL deficiency cosegregated with premature coronary artery disease in this kindred. Pedigree analysis was suggestive of a codominant familial disease. Poiymerase chain reaction amplification of the apoA-I gene of the proband, followed by subcloning and sequencing, did not reveal any mutation in either the coding regions or intron-exon junctions. A kinetic study using deuterated leucine to endogenoushy label apoA-I was performed to elucidate the metabolic basis of the apoA-I deficiency. We demonstrated marked hypercatabolism of apoA-I in the proband, with a fractional catabolic rate more than 10 times faster than normal; the plasma residence time of apoA-I in the proband was only 038 day compared with 4.10 days in a control subject The apoA-I production rate was also substantially decreased in the proband. The association of a normal apoA
A 17 year old female patient with hypertension, amenorrhoea and hirsutism was found to have subnormal levels of plasma and urinary cortisol, significant plasma levels of Reichstein's compound S and 21-deoxycortisol, high urinary levels of THS and pregnanetriolone as well as elevated levels of plasma and urinary testosterone. Treatment with 0.5 mg/day of dexamethasone or 25 mg/day cortisone reduced her hypertension and restored her menstrual cycles, but also resulted in the development of moon face, body striae and a gain in weight. Lower doses of cortisone were without effect. The deficient cortisol production coupled with the presence of unusual intermediates such as Reichstein's compound S and 21-deoxycortisol can be explained by a shift in the substrate specificity of 11β-hydroxylase from C-21-hydroxylated substrates (i.e. compound S) to C-21-deoxy substrates (i.e. 17-hydroxyprogesterone).
11 beta-Hydroxydehydroepiandrosterone has been isolated from the urine of a 14-yr-old girl with a virilizing adrenal adenoma. Its excretion was estimated to be 0.4 mg/24 h by gas chromatography and the compound was further identified by mass spectrometry. When [7-3H]dehydroepiandrosterone was incubated with mitochondria prepared from the adenoma, approximately 10% was converted to 11 beta-hydroxydehydroepiandrosterone. The identity of the radioactive 11 beta-hydroxydehydroepiandrosterone was verified by reversed isotopic dilution, its conversion to 11 beta-hydroxyandrostenedione, and its mobility in several chromatographic systems. This is the first demonstration of an 11 beta-hydroxylase from a human source having an affinity for dehydroepiandrosterone.
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