Histochemistry of the 3β-hydroxysteroid, 17β-hydroxysteroid and 3α-hydroxysteroid dehydrogenases in human salivary glands
14
Citation
20
Reference
10
Related Paper
Keywords:
Hydroxysteroid Dehydrogenases
Hydroxysteroid
Hydroxysteroid Dehydrogenases
We previously reported that the human Y' bile acid binder, which has higher bile acid binding affinities than rat Y' binders (3 alpha-hydroxysteroid dehydrogenases), has dihydrodiol dehydrogenase activity and is different from 3 alpha-hydroxysteroid dehydrogenases. In this study, 3 alpha-hydroxysteroid dehydrogenases and 3 beta-hydroxysteroid dehydrogenase were purified from human liver, and bile acid binding affinities and enzyme kinetics of the 3 alpha-hydroxysteroid dehydrogenases were studied. On chromatofocusing of pooled Affigel blue fraction of the Y' fraction, three 3 alpha-hydroxysteroid dehydrogenase peaks eluted at pH 6.0, 5.7 and 5.4. These peaks did not bind bile acids, and further purification by hydroxyapatite-high-performance liquid chromatography gave pure 3 alpha-hydroxysteroid dehydrogenases with identical M(r) (36,000) having dihydrodiol dehydrogenase activity. 3 beta-Hydroxysteroid dehydrogenase was eluted together with Y' bile acid binder at pH 7.2 on chromatofocusing and was separated from Y' bile acid binder on hydroxyapatite-high-performance liquid chromatography as a pure protein with M(r) 32,000. The apparent Kms of 3 alpha-hydroxysteroid dehydrogenases were similar to those of rat enzymes. In conclusion, we purified human hepatic 3 alpha-hydroxysteroid dehydrogenases, which have similar characteristics to rat enzymes, but do not bind bile acids or reduce bile acid precursors. These data further support the importance of human bile acid binder in intracellular bile acid transport in the human liver.
Chromatofocusing
Hydroxysteroid Dehydrogenases
Hydroxysteroid Dehydrogenases
Hydroxysteroid
Cite
Citations (13)
Hydroxysteroid Dehydrogenases
Hydroxysteroid Dehydrogenases
Detoxication
Hydroxysteroid
Steroid biosynthesis
Cite
Citations (1)
After cultivation of Streptomyces hydrogenans in the presence of different steroids the activity of both 3 alpha, 20 beta-hydroxysteroid dehydrogenase and 3 beta, 17 beta-hydroxysteroid dehydrogenase was determined in the cell homogenate of the microorganism. By comparing the efficacy of the steroids to increase enzyme activities, steroids could be divided into 3 groups: a) steroids which stimulated preferentially the activity of 3 alpha, 20 beta-hydroxysteroid dehydrogenase (e. g., corticosterone), b) steroids which stimulated preferentially 3 beta, 17 beta-hydroxysteroid dehydrogenase (estradiol-17 beta), and c) those behaving intermediately (e. g., progesterone, 5 alpha -dihydrotestosterone). Highest 3 beta, 17 beta-hydroxysteroid dehydrogenase activity could be measured 2 h after addition of 5 alpha-dihydrotestosterone to the culture medium. The activity of 3 alpha, 20 beta-hydroxysteroid dehydrogenase, however, increased continuously up to 4 h. 3 alpha, 20 beta-hydroxysteroid dehydrogenase and 3 beta, 17 beta-hydroxysteroid dehydrogenase syntheses seemed to be controlled by steroids in a non-coordinate manner.
Hydroxysteroid Dehydrogenases
Dihydrotestosterone
BETA (programming language)
Hydroxysteroid
Alpha (finance)
Hydroxysteroid Dehydrogenases
Cite
Citations (5)
Hydroxysteroid Dehydrogenases
Hydroxysteroid
BETA (programming language)
Dihydrotestosterone
Hydroxysteroid Dehydrogenases
Alpha (finance)
Cite
Citations (46)
A synthetic steroid (2α-cyano-4, 4, 17α-trimethyl-androst-5-en-17β-ol-3-one) behaves as a stoichiometric inhibitor of 3β-hydroxysteroid dehydrogenase in a purified extract of testosterone-induced Pseudomonas testosteroni, and in homogenates of bovine and rat adrenal tissues. This inhibitor titrates the activity of the bacterial 3(17-)β-hydroxysteroid dehydrogenase with three 3β-and two 17β-hydroxysteroidal substrates, and that of the mammalian 3β-hydroxysteroid dehydrogenases with the 3β-hydroxysteroidal substrates. Human adrenal tissue, hyperplastic due to a selectively deficient activity of 3β-hydroxysteroid dehydrogenase, does not bind the inhibitor, while suitable control tissue does. The inhibitor-binding capacity of the purified bacterial preparation is of the same order of magnitude as the amount of inhibitor required to activate the 3β-hydroxysteroid dehydrogenase in this preparation. These results suggest that the prolonged effects of this steroidal cyano-ketone in vivo result, at least in part, from its extraordinarily tight binding very near to the active center of 3βhydroxysteroid dehydrogenase.
Hydroxysteroid Dehydrogenases
Hydroxysteroid Dehydrogenases
Hydroxysteroid
Cite
Citations (32)
SUMMARY Five male foetal mice were killed daily from the 11th day of gestation until term, the 21st day. Sections of testis from every animal were incubated with three steroid substrates to demonstrate 3β-hydroxysteroid dehydrogenase histochemically. The substrates were (1) 3β-hydroxypregn-5-en-20-one (pregnenolone), (2) 3β,17α-dihydroxypregn-5-en-20-one (17α-hydroxypregnenolone), and (3) 3β-hydroxyandrost-5-en-17-one (DHA). With pregnenolone as substrate 3β-hydroxysteroid dehydrogenase activity was demonstrable from the 11th day, when the testis is first histologically recognizable, until the end of gestation. Using 17α-hydroxypregnenolone, no 3β-hydroxysteroid dehydrogenase activity was present in the foetal testis. With DHA as substrate weak activity was first seen in the testis of the 15-day foetal mouse, and increased steadily thereafter. These findings are thought to support the concept of substrate-specific 3β-hydroxysteroid dehydrogenases.
Hydroxysteroid Dehydrogenases
Hydroxysteroid Dehydrogenases
Hydroxysteroid
Cite
Citations (23)
Abstract After cultivation of Streptomyces hydrogenans in the presence of different steroids the activity of both 3α,20β‐hydroxysteroid dehydrogenase and 3β, 17β‐hydroxysteroid dehydrogenase was determined in the cell homogenate of the microorganism. By comparing the efficacy of the steroids to increase enzyme activities, steroids could be divided into 3 groups: a) steroids which stimulated preferentially the activity of 3α,20β‐hydroxysteroid dehydrogenase (e. g., corticosterone), b) steroids which stimulated preferentially 3β,17β‐hydroxysteroid dehydrogenase (estradiol‐17β), and c) those behaving intermediately ( e. g. , progesterone, 5α‐dihydrotestosterone). Highest 3β, 17β‐hydroxysteroid dehydrogenase activity could be measured 2 h after addition of 5α‐dihydrotestosterone to the culture medium. The activity of 3α, 20β‐hydroxysteroid dehydrogenase, however, increased continuously up to 4 h. 3α,20β‐hydroxysteroid dehydrogenase and 3β,17β‐hydroxysteroid dehydrogenase syntheses seemed to be controlled by steroids in a non‐coordinate manner.
Hydroxysteroid Dehydrogenases
Dihydrotestosterone
Hydroxysteroid
Hydroxysteroid Dehydrogenases
Cite
Citations (0)
Abstract 11β‐hydroxysteroid dehydrogenases regulate glucocorticoid concentrations and 17β‐hydroxysteroid dehydrogenases regulate estrogen and androgen concentrations in mammals. Phylogenetic analysis of the sequences from two 11β‐hydroxysteroid dehydrogenases and four mammalian 17β‐hydroxysteroid dehydrogenases indicates unusual evolution in these enzymes. Type 1 11β‐ and 17β‐hydroxysteroid dehydrogenases are on the same branch; Type 2 enzymes cluster on another branch with β‐hydroxybutyrate dehydrogenase, 11‐ cis retinol dehydrogenase and retinol dehydrogenase; Type 3 17β‐hydroxysteroid dehydrogenase is on a third branch; while the pig dehydrogenase clusters with a yeast multifunctional enzyme on a fourth branch. Pig 17β‐hydroxysteroid dehydrogenase appears to have evolved independently from the other three 17β‐hydroxysteroid dehydrogenase dehydrogenases; in which case, the evolution of 17β‐hydroxysteroid dehydrogenase activity is an example of functional convergence. The phylogeny also suggests that independent evolution of specificity toward C11 substituents on glucocorticoids and C17 substituents on androgens and estrogens has occurred in Types 1 and 2 11β‐ and 17β‐hydroxysteroid dehydrogenases.
Hydroxysteroid Dehydrogenases
Hydroxysteroid Dehydrogenases
Hydroxysteroid
Cite
Citations (50)
Enzyme induction in Streptomyces hydrogenans Comparison of the effects of different steroids to increase the activity of 3α,20β-hydroxysteroid dehydrogenase and of 3β,17β-hydroxysteroid dehydrogenase was published in Band 22, Heft 5 1982 on page 287.
Hydroxysteroid Dehydrogenases
Hydroxysteroid Dehydrogenases
Hydroxysteroid
Cite
Citations (0)
Hydroxysteroid Dehydrogenases
Hydroxysteroid
Hydroxysteroid Dehydrogenases
Cite
Citations (14)