Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0338671 (Steroids)
 9,479 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sensitive methods for quantifying androgens were lacking. Therefore, a relatively simple procedure for separating steroids was combined with highly specific assay methods so that eight androgens could be measured with high accuracy, precision and sensitivity. Semi-automated separations on Sephadex LH-20 columns used heptane:methylene chloride:ethanol:water (50:50:1:0.12) and a flow rate of 17.0 min/ml. The six peaks eluted contained androstenedine; androsterone, epiandrosterone and dihydrotestosterone; testosterone and dehydroepiandrosterone; 3alpha-androstanediol; 3beta-androstanediol; and androstenediol. Androstenedione, dehydroepiandrosterone and androstenediol were quantified using specific antisera (sensitivity less than or equal to 75 pg). Testosterone and dihydrotestosterone were measured by competitive protein-binding assays using rabbit TeBG (sensitivity less than or equal to 150 pg). 3alpha- and 3beta-androstanediol were similarly assayed using human TeBG (sensitivity approximately 150 pg). Androsterone was reduced with NaBH4 and the resulting 3alpha-androstanediol was assayed using human TeBG (sensitivity approximately 200 pg). Inter- and intra-assay variations were less than 10% for radioimmunoassays and less than 16% for competitive protein-binding assays over the entire dose response curve.
Steroids 1976 Nov
PMID:Simultaneous ultramicroanalysis of both 17-keto-and 17beta-hydroxy androgens in biological fluids. 13 14

Androsterone (3alpha-hydroxy-5alpha-androstan-17-one), 5alpha-androstane-3alpha, 17beta-diol and 5alpha-androstane-3beta, 17beta-diol were conjugated at C-16 through sulfur to bovine and human serum albumin. Rabbits injected with these conjugates produced antibodies suitable for radioimmunoassays of these hormone metabolites. Samples were purified on Sephadex LH-20 columns. Levels of these steroids were measured in a rat blood serum pool and in ovarian tissue extract pools.
Steroids 1977 Nov
PMID:Radioimmunoassays for androsterone, 5alpha-androstane-3alpha, 17beta-diol and 5alpha-androstane-3beta, 17beta-diol. 61 34

The metabolism of 1,2-3H-androstenedione was studied in 2 cell lines, MCF-7 (estrogen responsive) and BT-20 (estrogen nonresponsive) over 48 hrs. Water soluble and unconjugated metabolites were separated by solvent partition and the former was submitted to chromatography on Sephadex LH-20 and enzyme hydrolysis. The resulting unconjugated steroids were separated by paper chromatography and identities were established by reverse isotope dilution. The unconjugated steroids initially obtained were separated by chromatography and identified by reverse isotope dilution. About 70% of the androstenedione was metabolized by both cell lines. However, the respective conversions to conjugates by MCF-7 and BT-20 were 31% and 0.32%. In the former, glucosiduronates predominated (94%) and consisted of androsterone (55%), etiocholanolone (9.4%) and androstanediol (5alpha-androstane-3alpha,17beta-diol) (9.3%). Androsterone comprised most of the unconjugated metabolites in both cell lines. Androstanediol was found in both cell lines, 2% in MCF-7 and 12% in BT-20. Testosterone, 5alpha-androstane-3,17-dione and 3beta-hydroxy-5alpha-androstan-17-one were isolated only from MCF-7. The metabolism of 3H-estriol was studied in a similar way. Both cell lines produced about equal amounts of estriol-3-sulfate (9%) and a compound with properties of estriol-3-glucosiduronate (0.15--0.5%). The results worthy of emphasis are: 1. The far greater conjugation of androgens exhibited by the MCF-7 cell lines as compared to the BT-20 cell lines; 2. In MCF-7, the high conversion of androstenedione to etiocholanolone (glucosiduronate form), a metabolite reported to form only in liver and sebaceous cysts; 3. The possible formation in both cell lines of estriol-3-glucosiduronate, normally a metabolite of the intestine.
Steroids 1978 Dec
PMID:Steroid metabolism in human breast cancer cell lines. 73 1

Details of a sensitive and specific radioimmunoassay for androsterone (1) and androsterone sulfate in plasma have been presented. Benzene extracts of plasma were chromatographed on alumina to isolate the androsterone fraction either (a) directly after extraction (A) or (b) after solvolysis (AS). Following treatment with rabbit anti-A-17-BSA, antibody bound steriod was precipitated by ammonium sulfate. Androsterone concentrations in normal male plasma averaged 57 +/- 24 (S.D.) ng/dl, range 35-135 ng/dl and for normal women, 44 +/- 21 (S.D.) ng/dl, range 18-98 ng/dl. Androsterone sulfate concentrations were: males 55 +/- 28 mug/dl (range 10-114 mug/dl); premenopausal females 52+/- 31 mug/dl (range 16-318 mug/dl).
Steroids 1976 Jun
PMID:Radioimmunoassay of androsterone and androsterone-3-sulfate in plasma. 94 Nov 89

The pattern of androgenic metabolites in blood, muscle, caput and cauda epididymidis has been investigated in functionally hepatectomized 24 hours castrated rats, 3 hours after the intra-muscular injection of 200 muCi of 3H-3H-3alpha-diol. Identification of the radioactive metabolites showed only negligible differences between the epididymal regions. In both caput and cauda the main metabolite was DHT (17beta-hydroxy-5alpha-androstane-3-one); 3alpha- and 3beta-diol, androsterone (3alpha-hydroxy-5alpha-androstane-17-one), 5-A-dione (5alpha-androsterone-3, 17-dione), delta16-3alpha-01 (kalpha-androst-16-en-3alpha-01), delta16-3beta-01 (5alpha-androst-16-en-3alpha-01) and delta16-3-one (5alpha-androst-16-en-3-one) were also present. Androsterone and 3alpha-diol were the predominant metabolites in blood and muscle. No delta16 compounds could be detected and in constrast to epididymis, more than 50% of the radioactivity was associated with polar compounds. From determination of total radioactivity, it was seen that retention by epididymis varied from two to four times that of muscle. Purification and identification of the radioactivity associated with the nuclear fraction demonstrated that DHT was the only nuclear bound androgen. It is suggested from these results that at least one effect of 3alpha-diol on the rat epididymis is exerted through its conversion to DHT.
Steroids 1976 Nov
PMID:Androgen metabolism by rat epididymis. 5. Metabolic conversion and nuclear binding after injection of 5alpha-androstane-3alpha, 17beta-diol, in vivo. 101 38

The 3alpha,5alpha- and 3alpha,5beta-reduced derivatives of progesterone, deoxycorticosterone, dehydroepiandrosterone and testosterone enhance GABAergic neurotransmission and produce inhibitory neurobehavioral and anti-inflammatory effects. Despite substantial information on the progesterone derivative (3alpha,5alpha)-3-hydroxypregnan-20-one (3alpha,5alpha-THP, allopregnanolone), the physiological significance of the other endogenous GABAergic neuroactive steroids has remained elusive. Here, we describe the validation of a method using gas chromatography-mass spectrometry to simultaneously identify serum levels of the eight 3alpha,5alpha- and 3alpha,5beta-reduced derivatives of progesterone, deoxycorticosterone, dehydroepiandrosterone and testosterone. The method shows specificity, sensitivity and enhanced throughput compared to other methods already available for neuroactive steroid quantification. Administration of pregnenolone to rats and progesterone to women produced selective effects on the 3alpha,5alpha- and 3alpha,5beta-reduced neuroactive steroids, indicating differential regulation of their biosynthetic pathways. Pregnenolone administration increased serum levels of 3alpha,5alpha-THP (+1488%, p<0.001), (3alpha,5alpha)-3,21-dihydroxypregnan-20-one (3alpha,5alpha-THDOC, +205%, p<0.01), (3alpha,5alpha)-3-hydroxyandrostan-17-one (3alpha,5alpha-A, +216%, p<0.001), (3alpha,5alpha,17beta)-androstane-3,17-diol (3alpha,5alpha-A-diol, +190%, p<0.01). (3alpha,5beta)-3-hydroxypregnan-20-one (3alpha,5beta-THP) and (3alpha,5beta)-3-hydroxyandrostan-17-one (3alpha,5beta-A) were not altered, while (3alpha,5beta)-3,21-dihydroxypregnan-20-one (3alpha,5beta-THDOC) and (3alpha,5beta,17beta)-androstane-3,17-diol (3alpha,5beta-A-diol) were increased from undetectable levels to 271+/-100 and 2.4+/-0.9 pg+/-SEM, respectively (5/8 rats). Progesterone administration increased serum levels of 3alpha,5alpha-THP (+1806%, p<0.0001), 3alpha,5beta-THP (+575%, p<0.001), 3alpha,5alpha-THDOC (+309%, p<0.001). 3alpha,5beta-THDOC levels were increased by 307%, although this increase was not significant because this steroid was detected only in 3/16 control subjects. Levels of 3alpha,5alpha-A, 3alpha,5beta-A and pregnenolone were not altered. This method can be used to investigate the physiological and pathological role of neuroactive steroids and to develop biomarkers and new therapeutics for neurological and psychiatric disorders.
Steroids
PMID:Simultaneous quantification of GABAergic 3alpha,5alpha/3alpha,5beta neuroactive steroids in human and rat serum. 1917 Nov 60