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1.
Zygote ; 20(2): 181-92, 2012 May.
Article in English | MEDLINE | ID: mdl-21729379

ABSTRACT

In vitro folliculogenesis could be a new technology to produce mature oocytes from immature follicles that have been isolated from cryopreserved or fresh ovarian tissue. This technique could also be a tool for evaluation of oocyte quality and/or for determination of follicular parameters during follicular growth. Our objective was to characterize in mice the secretion profiles of follicles that had been isolated mechanically during in vitro follicular growth and in relation to the growth curve. Early preantral follicles from fresh prepubertal and adult mouse ovaries or frozen-thawed prepubertal mouse ovaries were cultured individually in microdrops under oil for 12 days. Each day, two perpendicular diameters of the follicles were measured. From day-3 to day-12 of culture, culture medium was collected and preserved for determination of inhibin B, anti-Müllerian hormone (AMH) and estradiol levels. At the end of the culture, after maturation, the status of the oocyte was evaluated. Follicular growth and their individual hormone production did not always correlate. Inhibin B was never secreted from follicles of less than 200 µm diameter, whether the follicles were examined when fresh or after freezing-thawing. Estradiol secretion was never observed in frozen-thawed follicles. AMH was mainly secreted between day-3 and day-9. Despite similar morphological aspects at the start of culture, follicles selected for in vitro folliculogenesis were found to be heterogeneous and differed in their ability to grow and to produce hormones, even if they had similar growth curves. Follicles from frozen-thawed ovaries developed slowly and produced fewer hormones than freshly collected follicles.


Subject(s)
Ovarian Follicle/growth & development , Ovarian Follicle/metabolism , Ovary , Animals , Anti-Mullerian Hormone/metabolism , Cryopreservation/methods , Estradiol/metabolism , Female , Inhibins/metabolism , Mice , Mice, Inbred C57BL , Oocytes/physiology , Puberty , Tissue Culture Techniques
2.
Ann Biol Clin (Paris) ; 66(5): 537-47, 2008.
Article in French | MEDLINE | ID: mdl-18957343

ABSTRACT

Today, serum antimullerian hormone (AMH) is considered as an interesting marker of fertility potential in women to determine follicular status and in men to evaluate testicular function. We study analytical and clinical characteristics of two AMH commercialized immunoassays: Immunotech and DSL methods. The detection limits (close to 0.13 ng/mL), functional sensitivities (close to 0.30 ng/mL) are equivalent, and imprecision results are acceptable for entirely manual assays. The Immunotech method is linear within the calibration range (up to 21 ng/mL) and the DSL method presents a lack of linearity making it accurate only up to 11 ng/mL (and not up to 14 ng/mL as it is indicated by the manufacturer). The two methods allow to measure human AMH, don't cross react with TGF-beta superfamily proteins and the DSL immunoassay recognize mouse (25%), rat (68%) and calf (100%) AMH. The comparison between the two methods (from 0.3 to 200 ng/mL) shows a good correlation (r = 0.979) with not statistically different results (p = 0.31). From a clinical point of view, the two methods allow the evaluation of follicular status in normo-ovulatory women and in women with polycystic ovary syndrome. Results are in agreement with studies showing that AMH serum concentration is strongly correlated with the number of antral follicles. In conclusion, the Immunotech method seems to be more efficient than the DSL method even if the two methods are suitable for clinical applications needing AMH measurements.


Subject(s)
Anti-Mullerian Hormone/blood , Disorders of Sex Development/blood , Enzyme-Linked Immunosorbent Assay/methods , Hirsutism/blood , Hyperandrogenism/blood , Infertility, Female/blood , Menstruation Disturbances/blood , Polycystic Ovary Syndrome/blood , Adult , Amenorrhea/blood , Child , Female , Humans , Linear Models , Male , Menstrual Cycle , Oligomenorrhea/blood , Reproducibility of Results , Retrospective Studies , Sensitivity and Specificity , Statistics, Nonparametric
3.
Eur J Clin Nutr ; 61(5): 647-54, 2007 May.
Article in English | MEDLINE | ID: mdl-17151588

ABSTRACT

BACKGROUND: There is no single universally accepted biochemical marker of nutritional status in the elderly. Many markers are affected by non-nutritional factors. OBJECTIVE: The purpose of this study was to determine the biological parameters best related to anthropometric markers of malnutrition in an elderly polypathological population, and determine cutoff values for these potential parameters to diagnose malnutrition. DESIGN: This prospective study enrolled 116 elderly hospitalized patients and 76 elderly outpatients. Nutritional status (albumin, transthyretin, body mass index (BMI), skinfold thickness) and biological parameters (leptin, insulin-like growth factor-1 (IGF-1), IGF binding protein-1 (IGFBP-1), IGFBP-3, C-reactive protein (CRP), orosomucoid) were assessed. We defined malnutrition according to the lowest quartile of BMI and skinfold thickness measured in a large healthy elderly French sample population. RESULTS: In this sample of elderly patients (age: 85+/-7 years old), leptin concentration was the only biological parameter significantly related to nutrition status. Independent correlations were found between leptin concentration and BMI, skinfold thickness and sex. The relationship between nutritional status and leptin concentration is significantly different in each sex: the more the patients are undernourished, the lower the leptin concentration in both sexes. The optimal leptin cutoff value for the diagnosis of malnutrition in this population was 4 microg/l in men (sensitivity 0.89, specificity 0.82) and 6.48 microg/l in women (sensitivity 0.90, specificity 0.83). CONCLUSION: Leptin concentration is highly correlated with anthropometric data whereas albumin or transthyretin are known to be also influenced by morbidity and inflammatory conditions. Serum leptin concentration could be used for nutritional assessment in elderly patients with acute diseases.


Subject(s)
Geriatric Assessment , Leptin/blood , Malnutrition/blood , Nutrition Assessment , Nutritional Status , Acute Disease , Aged, 80 and over , Biomarkers/blood , Body Mass Index , Case-Control Studies , Diagnosis, Differential , Female , Health Status , Humans , Male , Malnutrition/diagnosis , Prospective Studies , Reference Standards , Reference Values , Sensitivity and Specificity , Serum Albumin/analysis , Sex Factors , Skinfold Thickness
4.
Hum Reprod ; 21(5): 1204-11, 2006 May.
Article in English | MEDLINE | ID: mdl-16476678

ABSTRACT

BACKGROUND: In primates, androgens can play a synergistic role with FSH in promoting the early follicular recruitment, which is critical in assisted reproduction technique programmes. OBJECTIVE: To assess whether poor responders can benefit from androgen application. METHODS: Inclusion criteria were a previous poor ovarian response to controlled ovarian stimulation and a decreased hormonal ovarian reserve. Selected women were randomized to receive either transdermal application of testosterone (n = 24) or placebo (n = 25) gel for 15 days before FSH treatment for a second IVF cycle. Similar GnRH analogue and equivalent FSH daily doses were used in both cycles. The primary outcome was the total number of oocytes retrieved. RESULTS: Testosterone gel application resulted in a significant increase in plasma testosterone levels but did not significantly improve the antral follicle count. Furthermore, after gel application, the main parameters of the ovarian response (numbers of pre-ovulatory follicles, total and mature oocytes and embryos) did not significantly differ between testosterone and placebo-treated patients. CONCLUSION: No significant beneficial effects of androgen administration on the ovarian response to FSH could be demonstrated. However, subsequent clinical trials are needed to determine whether an optimal dose and/or a longer duration of testosterone administration may be helpful.


Subject(s)
Fertilization in Vitro , Ovary/drug effects , Ovulation Induction , Testosterone/administration & dosage , Administration, Cutaneous , Adult , Double-Blind Method , Female , Follicle Stimulating Hormone/administration & dosage , Gels/administration & dosage , Gonadotropin-Releasing Hormone/administration & dosage , Humans
5.
J Nutr Health Aging ; 9(5): 327-9, 2005.
Article in English | MEDLINE | ID: mdl-16222398

ABSTRACT

The leptin, protein of 146 amino acids, produced gene ob (chromosome 7) acts via the hypothalamus on the control of energy balance. It is implied in the adequacy between the food intake and the energy expenditure, and maintains stable body mass. We studied leptine's diurnal rhythm in old person of more than 75 years in institution, according to its state of nutrition and the undercurrent events likely to modify it. The study subjects were divided in two groups according to BMI < or superior 20 kg/m2. In the group of the patients with BMI higher than 20 kg/m2, there exists a correlation of the variation of the plasma leptin levels according to the BMI. At the subjects having a BMI lower than 20 kg/m2, the plasma leptin level is higher than the awaited value and the Leptin/BMI ratio is increased significantly compared to the subjects having a BMI higher than 20 kg/m2 (p < 0,05). Reduced nutritional status has largely exceeded capacities of adaptation to the nutritional needs and the capacity of response to the stress via the leptin is very disturbed.


Subject(s)
Aging/physiology , Body Mass Index , Hospitalization , Leptin/blood , Aged , Aged, 80 and over , Circadian Rhythm , Female , Geriatric Assessment , Humans , Male , Nutrition Assessment , Nutritional Status
6.
Diabetologia ; 48(3): 519-28, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15729583

ABSTRACT

AIMS/HYPOTHESIS: The acute-phase proteins, serum amyloid As (SAA), are precursors of amyloid A, involved in the pathogenesis of AA amyloidosis. This work started with the characterisation of systemic AA amyloidosis concurrent with SAA overexpression in the subcutaneous white adipose tissue (sWAT) of an obese patient with a leptin receptor deficiency. In the present study a series of histopathological, cellular and gene expression studies was performed to assess the importance of SAA in common obesity and its possible production by mature adipocytes. MATERIALS AND METHODS: Gene expression profiling was performed in the sWAT of two extremely obese patients with a leptin receptor deficiency. Levels of the mRNAs of the different SAA isoforms were quantified in sWAT cellular fractions from lean subjects and from obese subjects before and after a very-low-calorie diet. These values were subsequently compared with serum levels of SAA in these individuals. In addition, histopathological analyses of sWAT were performed in lean and obese subjects. RESULTS: In sWAT, the expression of SAA is more than 20-fold higher in mature adipocytes than in the cells of the stroma vascular fraction (p<0.01). Levels of SAA mRNA expression and circulating levels of the protein are sixfold (p<0.001) and 3.5-fold (p<0.01) higher in obese subjects than in lean subjects, respectively. In lean subjects, 5% of adipocytes are immunoreactive for SAA, whereas the corresponding value is greater than 20% in obese subjects. Caloric restriction results in decreases of 45-75% in levels of the transcripts for the SAA isoforms and in circulating levels of the protein. CONCLUSIONS/INTERPRETATION: The results of the present study indicate that SAA is expressed by sWAT, and its production at this site is regulated by nutritional status. If amyloidosis is seen in the context of obesity, it is possible that production of SAA by adipocytes could be a contributory factor.


Subject(s)
Adipocytes/metabolism , Gene Expression Profiling , Nutritional Status , Obesity/physiopathology , Serum Amyloid A Protein/genetics , Adult , Diet, Reducing , Energy Intake , Female , Humans , Nutritional Physiological Phenomena , Premenopause , Receptors, Cell Surface/deficiency , Receptors, Cell Surface/genetics , Receptors, Cell Surface/metabolism , Receptors, Leptin , Reference Values , Skin
7.
Gynecol Obstet Fertil ; 32(9): 760-6, 2004 Sep.
Article in French | MEDLINE | ID: mdl-15380759

ABSTRACT

Inhibin B measurement is evolving as a very common prescription in woman's hypofertility diagnosis and follow-up. The aim of this short review of literature is to assess the pertinence of addition of this parameter in the evaluation of the ovarian reserve and in the follow-up of the ovary stimulation treatments. Many studies have been conducted but their results are controversial. According to a majority of authors, inhibin B assay does not systematically bring a discriminant input in borderline clinic cases, already documented by age, plasmatic FSH or even plasmatic estradiol, and echographic evaluation of number of antral follicles on day 3. Most recent publications however grant a growing positive interest in the inhibin B inclusion in the EFORT test as it allows to notably improve the evaluation of the ovarian reserve. Plasma inhibin B assay during the stimulation protocols does not seem to bring significant complementary information and, in any event, cannot be routinely prescribed for a therapeutic follow-up as long as there is no available rapid inhibin assay. Inhibin A evaluation is only performed in research protocols. Research developments regarding the regulation of the post-transfer luteal phase and the implantation mechanisms are still required to evaluate the accuracy of inhibin A as a marker of this still unknown stage.


Subject(s)
Infertility, Female , Inhibins/physiology , Female , Humans , Inhibins/analysis
8.
J Endocrinol Invest ; 14(7): 583-9, 1991.
Article in English | MEDLINE | ID: mdl-1940064

ABSTRACT

A 35-year-old patient and a 48-year-old patient with a benign feminizing Leydig cell tumor were treated just before orchiectomy with a GnRH agonist, respectively buserelin, administered subcutaneously for 7 days (500 micrograms/8 h) and intranasally for the following 7 days (400 micrograms/8 h), and long acting détryptoréline in a single im injection of 3.75 mg. After 10 days of treatment, breast pain was relieved. In the first patient, serum immunoassayable FSH and LH first rose and reached a peak by the first day, then decreased to nearly basal values; they unexpectedly rose again and the second peak was as high as the first one; they again decreased just before orchiectomy. The bioassayable to immunoassayable LH ratio rose and reached a peak on day 3; then it decreased and reached a nadir before orchiectomy. In the second patient, after the initial increase, FSH and LH decreased regularly with no subsequent increase. In both patients, an increase in plasma testosterone (T) and estradiol (E2) followed the first gonadotropin peak, then T and E2 decreased progressively and reached castration levels. It was thus possible to strongly inhibit both E2 tumoral secretion and T secretion. Our findings suggest that E2 tumoral secretion inhibition by GnRH agonists might be proposed as an alternative treatment to surgery, i.e. for patients who refuse orchiectomy or for whom surgery is contraindicated.


Subject(s)
Buserelin/pharmacology , Estradiol/metabolism , Leydig Cell Tumor/metabolism , Testicular Neoplasms/metabolism , Adult , Buserelin/therapeutic use , Estradiol/blood , Follicle Stimulating Hormone/blood , Humans , Kinetics , Leydig Cell Tumor/drug therapy , Leydig Cell Tumor/surgery , Luteinizing Hormone/blood , Male , Middle Aged , Orchiectomy , Testicular Neoplasms/drug therapy , Testicular Neoplasms/surgery , Testosterone/blood
9.
Chronobiol Int ; 6(3): 267-77, 1989.
Article in English | MEDLINE | ID: mdl-2805155

ABSTRACT

The circadian variations in plasma progesterone (P) and LH concentrations were investigated in six women, aged 23-40 years. All were studied in the mid-luteal phase (7 +/- 2 days after LH mid-cycle surge). Experiments were conducted in autumn and in spring. Blood samples were obtained every 15 min for 24 hr. Plasma P and LH concentrations were measured by RIA. Each subject's time-series was analysed using three methods; visual inspection (chronogram), spectral analysis to estimate component periods of rhythms (tau) and cosinor analysis to quantify the rhythms parameters. Marked temporal variations in plasma P concentration were observed in each subject. The maximal variations over a 24-hr period, ranged between 13-58.5 mmol/l. Differences related to sampling time were statistically validated by ANOVA (p less than 0.00001). Significant harmonic periods were detected by spectral analysis but differed among subjects. In all subjects but one, a circadian rhythm was detected. The acrophase location was similar (about 0700 hr) in the four subjects studied in autumn, but ranged from 1940 to 0320 hr in those studied in spring. An ultradian rhythm with tau = 8 hr was also validated in six time-series with similar acrophases (about 0200, 1000, and 1800 hr). Cosinor analysis of pooled data revealed that the 24-hr, 12-hr, and 8-hr rhythms were statistically significant (p = 0.001) in autumn. algebraic sum of these three cosine functions yielded a circadian waveform with peak-times occurring near 0300 and 1130 hr and a trough-time about 2200 hr. In spring, the circadian pattern appeared quite different, and peak-times were found near 0700 and 2000 hr, and trough-times near 0300 and 1500 hr. Furthermore, the 24-hr mean of P was higher in autumn (28.9 +/- 0.4 nmol/l) than in spring (17.2 +/- 0.4 nmol/l), p from ANOVA less than 0.00001. The evidence for a similar circadian LH pattern is not as strong. Seasonal, circadian and ultradian rhythms characterize the physiologic time structure of plasma P concentration in mid-luteal phase.


Subject(s)
Luteal Phase/physiology , Luteinizing Hormone/blood , Periodicity , Progesterone/blood , Activity Cycles/physiology , Adult , Circadian Rhythm/physiology , Female , Humans , Seasons
11.
Acta Endocrinol (Copenh) ; 115(3): 365-72, 1987 Jul.
Article in English | MEDLINE | ID: mdl-3113148

ABSTRACT

Two patients, aged 32 and 35 years, presented with gynaecomastia and a unilateral testicular tumour which proved to be a Leydig cell tumour. Pre-operative samples taken at 08.00 h on different days showed marked elevation of plasma oestradiol in the first patient, and very slight irregular oestradiol elevation in the second, plasma oestrone within the normal range in both patients, reduced plasma testosterone in the first patient and reduced or normal testosterone in the second, and low or low-normal serum LH and FSH in both patients. One of the patients received an oral dose of 100 mg of clomiphene citrate for 3 consecutive days which induced a rise in LH and FSH and a decrease in the 17-hydroxyprogesterone/androstenedione ratio. These data suggest the inhibiting effect of endogenous hyperoestrogenism on testicular steroidogenesis owing to both the reduction of gonadotropin secretion and a direct local negative effect on C 17,20-lyase. After human chorionic gonadotropin stimulation, oestradiol response was increased and abnormally prolonged, a finding which may be helpful when diagnosing a feminizing Leydig cell tumour; testosterone reached normal values. After removal of the tumoural testis, gynaecomastia regressed within a few days, gonadotropins increased, oestrogens dropped, testosterone and 5 alpha-dihydrotestosterone normalized in one patient but remained low in the other at day 30. The Leydig cells outside the tumour appeared morphologically normal, but the count gave evidence of juxtatumoural Leydig cell hyperplasia in areas where the tumour was well encapsulated while showing a significant reduction at a distance from the tumour and in the contralateral testis by comparison with control testes.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Feminization/blood , Leydig Cell Tumor/blood , Testicular Neoplasms/blood , Adult , Androstenedione/blood , Clomiphene/pharmacology , Estradiol/blood , Estrone/blood , Follicle Stimulating Hormone/blood , Humans , Hyperplasia , Leydig Cells/pathology , Luteinizing Hormone/blood , Male , Testosterone/blood
12.
J Endocrinol Invest ; 10(2): 187-93, 1987 Apr.
Article in English | MEDLINE | ID: mdl-3584858

ABSTRACT

A 32-year-old patient with a history of surgery for left gynecomastia four years previously presented with right gynecomastia; a tumor in the left testis proved to be a Leydig cell tumor. Preoperative investigations showed elevated but variable levels of plasma estradiol (E2) and estrone (E1), and reduced serum LH and FSH and plasma testosterone (T). After hCG stimulation, E2 response was increased and abnormally prolonged; T reached normal values, which has predictive value for a return to normal of post-operative T level. After left orchiectomy, gynecomastia regressed within a few days, gonadotropins increased by day 2, estrogens dropped by day 2 and were normal at day 7, T and 5 alpha-dihydrotestosterone dropped at day 2 but reached normal levels at day 16. Pathophysiology of these hormonal data are discussed. An incubation procedure with 3H testosterone showed an aromatase activity 21 times greater in the tumor than in normal peritumoral tissue, while the percentage of the volume occupied by Leydig cells was 34 times higher. This suggests that the aromatase activity of a single tumor cell is very similar to that of a normal Leydig cell. Furthermore, evidence of juxtatumoral Leydig cell hyperplasia in areas where the tumor was well encapsulated suggests the existence of a factor stimulating Leydig cell multiplication.


Subject(s)
Hormones/blood , Leydig Cell Tumor/metabolism , Testicular Neoplasms/metabolism , Adult , Androgens/blood , Aromatase/metabolism , Estrogens/blood , Gonadotropins, Pituitary/blood , Gynecomastia/etiology , Humans , Leydig Cell Tumor/pathology , Male , Testicular Neoplasms/pathology
13.
C R Seances Acad Sci III ; 292(9): 609-12, 1981 Mar 02.
Article in French | MEDLINE | ID: mdl-6263512

ABSTRACT

The metabolism, in vitro, of [6,7-3H]-oestrone-3-sulfate and [6,7-3H]-oestradiol-17beta-3-sulfate by the uteri of pregnant female Guinea-Pigs has been studied using 900 g supernatants. A hydrolysis of the sulfate moiety was observed: 35% of the radioactivity was recovered in the unconjugated fractions after 1 hr. of incubation. Gluruconide oestrogens were also recovered but the rate of synthesis was very low (3.6% after 1 hr.). OEstrone and oestradiol-17beta have been identified in unconjugated, glucuro and sulfo-conjugated fractions after incubation with the tritiated oestrogen sulfates.


Subject(s)
Estradiol/analogs & derivatives , Estrogens, Conjugated (USP)/metabolism , Estrone/analogs & derivatives , Pregnancy, Animal , Uterus/metabolism , Animals , Estradiol/metabolism , Estrone/metabolism , Female , Guinea Pigs , Hydrolysis , Kinetics , Pregnancy , Tritium
14.
Clin Chem ; 26(2): 190-3, 1980 Feb.
Article in English | MEDLINE | ID: mdl-7353263

ABSTRACT

We describe a mechanized method for determining total estrogens in plasma during the last trimester of pregnancy. This method involves rapid enzymic hydrolysis, automatic extraction (in a tube) with cyclohexane/ethyl acetate, purification of the extracted material by anion-exchange chromatography on a disposable "mini-column" of Dowex AG1 X 2 (acetate form), and continuous-flow fluorometric quantification. Conditions of hydrolysis and extraction were studied. The mean within-day imprecision (CV) was 7% and between-day imprecision was 8.1%. Sensitivity was 75 nmol/L of plasma. Results are obtained in 4 h. The technique is quite suitable for routine determinations: 90 assays can be done by a team of three technicians in one working day.


Subject(s)
Estrogens/blood , Fluorometry/methods , Female , Humans , Hydrolysis , Pregnancy , Pregnancy Trimester, Third , Time Factors
15.
Clin Chem ; 25(2): 230-4, 1979 Feb.
Article in English | MEDLINE | ID: mdl-215343

ABSTRACT

We describe a new method of extraction and purification of estrogens in low concentration in urine, involving a rapid enzymic hydrolysis of a 10-mL sample, automatic extraction (in a tube) with CHCl3/ethyl acetate, purification by chromatography on a disposable "mini-column" of AG 1-X2, and fluorometry by continuous flow according to Itrich's procedure [Acta Endocrinol. (Copenhagen) 35, 34 (1960)]. Conditions of hydrolysis, extraction, and purification were studied. Within-day precision (CV) was 7.5%, the mean between-day precision 8.5%. The sensitivity was 6 microgram of total estrogens per liter of urine. The specificity was assessed particularly by comparison with the results obtained by Schöller et al. [Acta Endocrinol. (Copenhagen) 57, suppl. 107 (1966)] and by gas-chromatography-mass-spectrometry. The normal limits as calculated by this technique were identical to values reported by others. The technique is rapid; results are obtained in 3 h. It is quite suitable for routine determinations: 100 assays can be done by a team of three technicians in one working day.


Subject(s)
Estrogens/urine , Chloroform , Chromatography, Ion Exchange , Estrogens/isolation & purification , Estrogens, Conjugated (USP)/urine , Female , Fluorometry , Humans , Hydrolysis , Methods
16.
Ann Biol Clin (Paris) ; 37(2): 89-94, 1979.
Article in French | MEDLINE | ID: mdl-475079

ABSTRACT

An automated method has been developed for the measurement of estrogens in the urine of pregnant and non-pregnant subjects. Using the Kober-Ittrich fluorescence procedure, this automated method was applied to the assay of estrogens in the purified urinary extracts of non-pregnant women, men or children. For pregnant-women it had been possible to simplify the purification of urinary extracts, and the reaction was performed directly on the sodium hydroxide fraction. The precision, accuracy, and sensitivity of the method had been analysed.


Subject(s)
Estrogens/urine , Autoanalysis/methods , Child , Estriol/urine , Estrone/urine , Female , Humans , Male , Pregnancy , Sodium Hydroxide , Spectrometry, Fluorescence/methods
17.
Steroids ; 32(3): 295-306, 1978 Oct.
Article in English | MEDLINE | ID: mdl-715821

ABSTRACT

Different cellular fractions of guinea-pig placenta were incubated in the presence of (7n-3H) testosterone. Microsomal aromatization of 3H-testosterone into estrone and estradiol-17beta was demonstrated in the presence of NADPH. The predominance of estrone after incubation with 17beta-hydroxylated precursors, (7n-3H) testosterone and (6,7-3H) estradiol-17beta, indicate that there is a microsomal 17beta-hydroxysteroid dehydrogenase activity. In this report, cytosolic sulfurylation of estrogens is demonstrated. This latter activity represents a quite original characteristic of the placental metabolism of estrogens in guinea-pigs. In contrast with the human placenta where there is considerable sulfatase activity, the guinea-pig placenta can sulfurylate estrogens.


Subject(s)
Estradiol/biosynthesis , Estrone/biosynthesis , Guinea Pigs/metabolism , Placenta/metabolism , Testosterone/metabolism , 17-Hydroxysteroid Dehydrogenases/metabolism , Animals , Chromatography, Gas , Chromatography, Thin Layer , Female , In Vitro Techniques , Pregnancy , Sulfates/metabolism
18.
Biochimie ; 60(8): 795-8, 1978.
Article in French | MEDLINE | ID: mdl-215238

ABSTRACT

The metabolism of [6,7-3H] estrone and of [6,7(3)H] estrone-3-sulfate have been comparatively studied in the maternal and fetal guinea-pig livers. The appearance of estradiol-17 beta resulting from the activity of the 17 beta-hydroxysteroid-dehydrogenase is more important in the fetal than in the maternal hepatic tissue. This suggests the direct transformation of estrone-3-sulfate into estradio-3-sulfate in the fetus. After incubation of the [3H] estrone, there is an abundant hepatic conjugation. The glycuroconjugated components are predominant, as well in the maternal as in the fetal hepatic tissue. For the latter-one the sulfoconjugation is inexistant. The sulfatasic activity shown after the incubation of [3H] estrone-3-sulfate is very low in the fetal hepatic tissue; in contrast, this activity is higher in the maternal tissue.


Subject(s)
Estrone/analogs & derivatives , Estrone/metabolism , Fetus/metabolism , Liver/metabolism , Animals , Estradiol/biosynthesis , Estrogens, Conjugated (USP)/metabolism , Female , Guinea Pigs , In Vitro Techniques , Liver/embryology
19.
C R Seances Soc Biol Fil ; 171(1): 20-7, 1977.
Article in French | MEDLINE | ID: mdl-143320

ABSTRACT

Slices of pregnant guinea pig liver were incubated with (6,7-3H)estrone and with (6,7-3H)estradiol. Free, glucuro- and sulfo-conjugated fractions were isolated by specific extraction and hydrolysis. The radioactivity distribution in these 3 fractions demonstrated a predominance of conjugated compounds (95% of isolated estrogens) with slightly more glucuro-conjugated than sulfo-conjugated compounds. After isolating estrogens by TLC, we were able to determine estrone and estradiol in these 3 fractions from incubations with 3H-estrone or with 3H-estradiol by means of specific activity recrystallisation. Estriol was determined in glucuro-and sulfo-conjugated fractions after incubation with 3H-estrone as well as in sulfo-conjugated fraction after incubation with 3H-estradiol. Glucuro- or sulfo-conjugated estrone was the predominant estrogen after incubation with 3H-estrone just as after incubation with 3H-estradiol. This led us to conclude to an important 17beta-hydroxysteroid-dehydrogenase activity. The 16alpha-hydroxylastic-activity is weaker since estriol represented only 1,43 % of estrogens isolated after incubation with 3H-estrone and 0.82% after incubation with 3H-estradiol.


Subject(s)
Estradiol/metabolism , Estrone/metabolism , Liver/metabolism , Pregnancy, Animal , 17-Hydroxysteroid Dehydrogenases/metabolism , Animals , Female , Guinea Pigs , In Vitro Techniques , Liver/enzymology , Mixed Function Oxygenases/metabolism , Pregnancy
20.
C R Acad Hebd Seances Acad Sci D ; 283(12): 1437-40, 1976 Nov 15.
Article in French | MEDLINE | ID: mdl-828539

ABSTRACT

The metabolism of (6-7-3H) estradiol-17 beta was studied in vitro in different cellular fractions of Guinea Pig placenta. The substrate was transformed into free as well as conjugated (hydrosoluble) estrone. It was thus possible to conclude, on one hand the existence of a very active microsomial 17 beta-hydroxy steroid-dehydrogenase and on the other the presence of a cytosolic system of estrogen conjugation. No estradiol-17 alpha or estriol were determined.


Subject(s)
Estradiol/metabolism , Estrone/biosynthesis , Placenta/metabolism , Animals , Cytosol/metabolism , Estradiol Dehydrogenases/metabolism , Female , Guinea Pigs , In Vitro Techniques , Microsomes/metabolism , Placenta/enzymology , Placenta/ultrastructure , Pregnancy
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