THE IN VITRO BIOSYNTHESIS OF 18-HYDROXYCORTICOSTERONE-4-14C BY SLICES OF ZONA GLOMERULOSA OF BEEF ADRENALS AND BY HUMAN ADRENALS

1963 ◽  
Vol 42 (3) ◽  
pp. 355-363 ◽  
Author(s):  
Thomas Sandor ◽  
André Lanthier
Keyword(s):  
Closed Form ◽  
Transformation Products ◽  
Zona Glomerulosa ◽  
Isotopic Dilution ◽  
Tissue Slices ◽  
Inactive Carrier ◽  
Tautomeric Forms ◽  
The Media ◽  
In Vitro Biosynthesis

ABSTRACT The in vitro steroidogenesis of the zona glomerulosa of beef adrenals and that of human adrenals was investigated. Tissue slices were incubated in a Krebs-Ringer - bicarbonate medium containing 200 mg% of glucose with progesterone-4-14C and corticosterone-4-14C as precursors. After incubation the media were extracted exhaustively with chloroform and the dry residue of the solvent extract fractionated on paper chromatographic systems. The identity of one of the 14C transformation products produced from both precursors was investigated in detail. The substance absorbed ultraviolet light (λmaxEtOH: 241 mμ), but reduced alkaline blue tetrazolium only very slowly. The mobility of the unknown alone and diluted with inactive carrier was identical with that of the 20→ 18 cyclic hemiketal of 18-hydroxycorticosterone. The identity of the biosynthetic material with the closed form of 18-hydroxycorticosterone was established by isotopic dilution techniques and the formation of derivatives. It was observed that the compound can exist in at least three different tautomeric forms. The yield of 18-hydroxycorticosterone with beef zona glomerulosa was 3.8% from progesterone and 6.8% from corticosterone.

THE IN VITRO BIOSYNTHESIS OF ESTRADIOL-17β-4-C14BY SURVIVING NORMAL AND STEIN–LEVENTHAL-TYPE OVARIAN SLICES

1963 ◽  
Vol 41 (3) ◽  
pp. 635-647 ◽  
Author(s):  
Alcide Chapdelaine ◽  
Thomas Sandor ◽  
André Lanthier
Keyword(s):  
Quantitative Difference ◽  
Human Chorionic Gonadotrophin ◽  
Isotopic Dilution ◽  
Tissue Slices ◽  
Medium Ph ◽  
Experimental Conditions ◽  
Chemical Derivatives ◽  
In Vitro Biosynthesis ◽  
Estradiol 17Β

The biological aromatization of androstenedione-4-C14, testosterone-4-C14, and dehydroepiandrosterone-4-C14by surviving human normal and Stein–Leventhal-type ovarian slices was investigated. The precursors were incubated with the tissue slices in a Krebs–Ringer–phosphate–glucose medium (pH 7.4) in an O2atmosphere at 37 °C for 6 and (or) 24 hours. As a cofactor, 1000 I.U. of human chorionic gonadotrophin was added to each incubation vessel. Both normal and polymicrocystic ovarian slices transformed the precursors partially to estradiol-17β. This compound was identified by isotopic dilution techniques and by the constancy of specific activities of its chemical derivatives. There was no significant qualitative or quantitative difference in the aromatization capacity of the two kinds of tissue. In addition, biosynthetic androstenedione-4-C14and testo-sterone-4-C14were positively identified. These experiments seem to indicate that under the experimental conditions used, the aromatization mechanism is functioning normally in Stein–Leventhal-type ovaries.

THE IN VITRO BIOSYNTHESIS OF ANDROGENIC STEROIDS BY HUMAN NORMAL AND »STEIN-LEVENTHAL TYPE« OVARIAN SLICES

1962 ◽  
Vol 39 (1) ◽  
pp. 145-153 ◽  
Author(s):  
André Lanthier ◽  
Thomas Sandor
Keyword(s):  
Paper Chromatography ◽  
Metabolic Activity ◽  
Transformation Products ◽  
Glucose Medium ◽  
Chromatographic Mobility ◽  
Tissue Slices ◽  
Mobility Studies ◽  
In Vitro Biosynthesis ◽  
Androgenic Steroids

ABSTRACT The in vitro biosynthesis of androgenic steroids by surviving human normal and »Stein-Leventhal type« ovarian slices was studied. The tissue slices were incubated in a Krebs-Ringer-phosphate-glucose medium (pH: 7.4) with pregnenolone, progesterone, 17α-hydroxyprogesterone and androstenedione added as substrates. The incubations were supplied with HCG as cofactor (1000 IU/vessel) and the reactions left to proceed for 6 or 24 hours. After incubation, the medium was extracted with chloroform and transformation products isolated by paper chromatography. Individual substances were characterized by chromatographic mobility studies, preparation of derivatives and spectrophotometric techniques. The following results were obtained: qualitatively no differences could be noted between the metabolic activity of ovarian slices of either origin. Quantitatively, »Stein-Leventhal type« slices showed an accelerated rate of production in all intermediary reactions, especially in the production of androstenedione and testosterone. In addition to the direct intermediaries, four C20 reduced transformation products of progesterone and 17α-hydroxyprogesterone were isolated from experiments involving both normal and micropolycystic ovarian slices.

THE IN VITRO BIOSYNTHESIS OF ESTRADIOL-17β-4-C14BY SURVIVING NORMAL AND STEIN–LEVENTHAL-TYPE OVARIAN SLICES

1963 ◽  
Vol 41 (1) ◽  
pp. 635-647
Author(s):  
Alcide Chapdelaine ◽  
Thomas Sandor ◽  
André Lanthier
Keyword(s):  
Quantitative Difference ◽  
Human Chorionic Gonadotrophin ◽  
Isotopic Dilution ◽  
Tissue Slices ◽  
Medium Ph ◽  
Experimental Conditions ◽  
Chemical Derivatives ◽  
In Vitro Biosynthesis ◽  
Estradiol 17Β

The biological aromatization of androstenedione-4-C14, testosterone-4-C14, and dehydroepiandrosterone-4-C14by surviving human normal and Stein–Leventhal-type ovarian slices was investigated. The precursors were incubated with the tissue slices in a Krebs–Ringer–phosphate–glucose medium (pH 7.4) in an O2atmosphere at 37 °C for 6 and (or) 24 hours. As a cofactor, 1000 I.U. of human chorionic gonadotrophin was added to each incubation vessel. Both normal and polymicrocystic ovarian slices transformed the precursors partially to estradiol-17β. This compound was identified by isotopic dilution techniques and by the constancy of specific activities of its chemical derivatives. There was no significant qualitative or quantitative difference in the aromatization capacity of the two kinds of tissue. In addition, biosynthetic androstenedione-4-C14and testo-sterone-4-C14were positively identified. These experiments seem to indicate that under the experimental conditions used, the aromatization mechanism is functioning normally in Stein–Leventhal-type ovaries.

Steroid sequestration within the rat adrenal zona glomerulosa

1988 ◽  
Vol 117 (2) ◽  
pp. 191-NP ◽  
Author(s):  
S. M. Laird ◽  
G. P. Vinson ◽  
B. J. Whitehouse
Keyword(s):  
Plasma Membrane ◽  
Density Gradient Centrifugation ◽  
Gradient Centrifugation ◽  
Zona Glomerulosa ◽  
Membrane Preparation ◽  
The Media ◽  
Considerable Concentration ◽  
Highly Correlated ◽  
Plasma Membrane Preparation

ABSTRACT Accumulated data from in-vitro experiments have suggested that 18-hydroxysteroids may be stored within the intact rat adrenal zona glomerulosa. The phenomenon was further investigated by comparing the amount of steroid remaining in the zona glomerulosa tissue with that secreted into the media during incubation in vitro. The results showed that 18-hydroxydeoxycorticosterone (18-OH-DOC) and 18-hydroxycorticosterone (18-OH-B) were retained within the tissue against a considerable concentration gradient, with smaller amounts of aldosterone and corticosterone. Lysis of the intact zona glomerulosa, by preincubation in distilled water, yielded an enriched plasma membrane preparation. After subsequent incubation in Krebs–Ringer bicarbonate this preparation contained significantly more 18-OH-DOC than did the intact tissue, suggesting that tissuesequestered 18-OH-DOC is normally metabolized to other products. These may include 18-OH-B and aldosterone. Fractionation of homogenized intact zona glomerulosa and the enriched plasma membrane preparation by density gradient centrifugation showed that tissue 18-OH-DOC banded in fractions of density 1·063– 1·21 g/ml and that its distribution was highly correlated with protein. Corticosterone, 18-OH-B and aldosterone banded like added free [3H]18-OH-DOC in fractions of density < 1·006 g/ml. The results suggest that 18-OH-DOC is the major sequestered steroid within the rat adrenal zona glomerulosa and that this sequestration is attributable to the association of 18-OH-DOC with a high-density component of the plasma membrane. J. Endocr. (1988) 117, 191–196

Effects of corticostatin-I on rat adrenal cells in vitro

1990 ◽  
Vol 125 (2) ◽  
pp. 287-292 ◽  
Author(s):  
T. Tominaga ◽  
J. Fukata ◽  
Y. Naito ◽  
Y. Nakai ◽  
S. Funakoshi ◽  
...  
Keyword(s):  
Specific Binding ◽  
Corticosterone Level ◽  
Inhibitory Effect ◽  
Zona Glomerulosa ◽  
Dependent Manner ◽  
Minimum Effective Concentration ◽  
Adrenal Cells ◽  
Aldosterone Production ◽  
The Media

ABSTRACT We have examined the mechanism by which corticostatin-I (CS-I) acts to attenuate ACTH-induced steroidogenesis in rat adrenal cells. CS-I inhibited ACTH-induced corticosterone production in a dosedependent manner, without any effects on the basal corticosterone level in adrenal cells. When the cells were stimulated by 100 pg ACTH/ml, the minimum effective concentration of CS-I was 100 ng/ml, and 0.3–1.0 μg CS-I/ml produced a 50% reduction of the stimulated corticosterone production. The inhibitory effect of CS-I on ACTH-stimulated corticosterone production became apparent within 15 min of incubation, and the effect was reversed quickly by the removal of CS-I from the media. CS-I had no effect on angiotensin II-stimulated aldosterone production by adrenal zona glomerulosa cells. CS-I also did not affect cyclic AMP- or forskolin-stimulated corticosterone production. In an in-vitro binding study using 125I-labelled CS-I, CS-I showed considerable specific binding to rat adrenal cells, and the binding competed with ACTH in a dose-dependent manner. These experiments suggest that CS-I competes with ACTH on their binding sites and exerts an inhibitory effect on the adrenal cells. Journal of Endocrinology (1990) 125, 287–292

scholarly journals In vitro biosynthesis of organic selenium by Lactobacillus casei from inorganic selenium forms

2021 ◽  
Vol 26 (5) ◽  
pp. 2916-2925
Author(s):  
MOHSEN ZOMMARA ◽  
◽  
ABD EL-AZIZ M. ABD EL-AZIZ ◽  
NOHA A. ELGAMMAL ◽  
JÓZSEF PROKISCH ◽  
...  
Keyword(s):  
Lactobacillus Casei ◽  
Starter Culture ◽  
Sodium Selenate ◽  
Bacterial Cells ◽  
Organic Form ◽  
Organic Selenium ◽  
The Media ◽  
In Vitro Biosynthesis ◽  
Cell Fractions

The bioconversion of selenium in the form of sodium selenite (Na2 SeO3 ) (SeIV) or sodium selenate (Na2 SeO4 ) (SeVI) to organic form by Lactobacillus casei (L. casei) was investigated in vitro. MRS media was supplemented with 1, 2, 5, 10 or 20 ppm of Se, inoculated with 2% starter culture with about 105 cfu/ ml of L. casei and then incubated up to 24 hrs at 37o C. Increasing of selenite “Se(IV)” concentrations in the media markedly reduced the bacterial growth compared to selenate “Se(VI)” indicating cytotoxic effect of selenite. The media supplemented with 5 ppm or more of Se(IV) became reddish after 24 hr of incubation as a result of the formation of 100-200 nanometer particles of selenium (SeNPs). Se speciation of the cultured media supernatants and its corresponding cell fractions was carried out by HPLC-ICP-MS technique. The bioconversion rate of Se to organic form by L. casei was extremely higher in Se(IV) than Se(VI) in both fractions, however the media supernatant contained the highest content. Increasing the media Se content resulted in gradual increase of organic Se concentration in both cells and supernatant fractions. The medium supplemented with 1 ppm Se(IV) was completely depleted from the inorganic Se as it completely converted to organic form. Although the cell fractions from all Se(VI) supplemented media contained only organic Se, the media supernatant contained significant residual amount of the inorganic form. Our results demonstrate the ability of L. casei to convert Se(IV) or Se(VI) up to 20 ppm to organic form(s) either in the cultured media or inside the bacterial cells. However, Se(IV) but not Se(VI), at a limit concentration of 1 ppm, was completely converted and accumulated in an organic form in the cell fraction and the cultured medium.

THE METABOLISM OF ALDOSTERONE

1962 ◽  
Vol 39 (1) ◽  
pp. 87-102 ◽  
Author(s):  
Thomas Sandor ◽  
André Lanthier
Keyword(s):  
Human Kidney ◽  
Water Soluble ◽  
Tissue Slices ◽  
Kidney Slices ◽  
Liver Slices ◽  
Glucuronide Conjugation ◽  
The Media ◽  
Human Liver Slices ◽  
Acid Labile

ABSTRACT A study was made of the metabolism of synthetic dl- and d-aldosterone and biosynthetic d-aldosterone-4-14C by surviving human liver slices, and of the metabolism of d-aldosterone by human kidney slices. After incubation of aldosterone with the tissue slices in a Krebs-Ringer-phosphate glucose medium at 37° C, the media were subjected to fractional hydrolysis and extracted with chloroform. In this way, it was possible to study not only the metabolites of the substrate but also the formation of water soluble conjugates of these metabolites and of aldosterone. It was found that the major in vitro metabolite of aldosterone, using liver slices as a source of enzymes, was the glucuronide of a Ring A reduced α-ketolic steroid (A2). It was possible to show that this metabolite was identical to the tetrahydroaldosterone found in glucuronide conjugation in human urine. In addition, several other metabolites were isolated but in smaller quantities. These include metabolite A1, a possible stereoisomer of A2, two Δ4-3-ketonic, non reducing metabolites and a number of 14C substances characterized only by chromatographic mobilities. Chemically unchanged aldosterone was present in free, glucuronide and acid labile conjugation. Human kidney slices, in addition to producing small amounts of A2, did conjugate aldosterone in both the glucuronide and acid labile form. The intravenous infusion of d-aldosterone to an adrenalectomized patient resulted in the urinary excretion of A2-glucuronide, aldosterone-glucuronide and the mild acid labile aldosterone conjugate.

scholarly journals Degradation Products of Polychlorinated Biphenyls and Their In Vitro Transformation by Ligninolytic Fungi

Toxics ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 81
Author(s):  
Kamila Šrédlová ◽  
Kateřina Šírová ◽  
Tatiana Stella ◽  
Tomáš Cajthaml
Keyword(s):  
Polychlorinated Biphenyls ◽  
Extracellular Enzymes ◽  
Degradation Products ◽  
Transformation Products ◽  
Irpex Lacteus ◽  
Chlorobenzoic Acid ◽  
Ligninolytic Fungi ◽  
Wide Range ◽  
Pcb Metabolites

Metabolites of polychlorinated biphenyls (PCBs)—hydroxylated PCBs (OH‑PCBs), chlorobenzyl alcohols (CB‑OHs), and chlorobenzaldehydes (CB‑CHOs)—were incubated in vitro with the extracellular liquid of Pleurotus ostreatus, which contains mainly laccase and low manganese-dependent peroxidase (MnP) activity. The enzymes were able to decrease the amount of most of the tested OH‑PCBs by > 80% within 1 h; the removal of more recalcitrant OH‑PCBs was greatly enhanced by the addition of the laccase mediator syringaldehyde. Conversely, glutathione substantially hindered the reaction, suggesting that it acted as a laccase inhibitor. Hydroxylated dibenzofuran and chlorobenzoic acid were identified as transformation products of OH‑PCBs. The extracellular enzymes also oxidized the CB‑OHs to the corresponding CB‑CHOs on the order of hours to days; however, the mediated and nonmediated setups exhibited only slight differences, and the participating enzymes could not be determined. When CB‑CHOs were used as the substrates, only partial transformation was observed. In an additional experiment, the extracellular liquid of Irpex lacteus, which contains predominantly MnP, was able to efficiently transform CB‑CHOs with the aid of glutathione; mono‑ and di-chloroacetophenones were detected as transformation products. These results demonstrate that extracellular enzymes of ligninolytic fungi can act on a wide range of PCB metabolites, emphasizing their potential for bioremediation.

scholarly journals Lignans of Sesame (Sesamum indicum L.): A Comprehensive Review

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 883
Author(s):  
Mebeaselassie Andargie ◽  
Maria Vinas ◽  
Anna Rathgeb ◽  
Evelyn Möller ◽  
Petr Karlovsky
Keyword(s):  
Biological Activities ◽  
Chemical Properties ◽  
Transformation Products ◽  
Extensive Literature ◽  
Controversial Issues ◽  
Sesame Seeds ◽  
Historical Texts ◽  
Health Promoting ◽  
Processed Products

Major lignans of sesame sesamin and sesamolin are benzodioxol--substituted furofurans. Sesamol, sesaminol, its epimers, and episesamin are transformation products found in processed products. Synthetic routes to all lignans are known but only sesamol is synthesized industrially. Biosynthesis of furofuran lignans begins with the dimerization of coniferyl alcohol, followed by the formation of dioxoles, oxidation, and glycosylation. Most genes of the lignan pathway in sesame have been identified but the inheritance of lignan content is poorly understood. Health-promoting properties make lignans attractive components of functional food. Lignans enhance the efficiency of insecticides and possess antifeedant activity, but their biological function in plants remains hypothetical. In this work, extensive literature including historical texts is reviewed, controversial issues are critically examined, and errors perpetuated in literature are corrected. The following aspects are covered: chemical properties and transformations of lignans; analysis, purification, and total synthesis; occurrence in Seseamum indicum and related plants; biosynthesis and genetics; biological activities; health-promoting properties; and biological functions. Finally, the improvement of lignan content in sesame seeds by breeding and biotechnology and the potential of hairy roots for manufacturing lignans in vitro are outlined.

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