Stimulatory and inhibitory influences of serum from pregnant women on aromatase activity of immature rat Sertoli cells

1989 ◽  
Vol 121 (2) ◽  
pp. 265-269 ◽  
Author(s):  
M. Simoni ◽  
S. A. Khan ◽  
Ch. De Geyter ◽  
E. Nieschlag
Keyword(s):  
Pregnant Women ◽  
Sertoli Cells ◽  
Aromatase Activity ◽  
Response Curves ◽  
Sharp Drop ◽  
Immature Rat ◽  
Estrogen Production ◽  
Specific Radioimmunoassay ◽  
Dependent Inhibition ◽  
Dose Dependent

Abstract. Effects of serum from pregnant women on basal and FSH (or cAMP) stimulated aromatase activity of immature rat Sertoli cells in primary culture were studied. Pregnancy serum caused a dose-dependent stimulation of Sertoli cell aromatase activity and the response curves were parallel to those obtained with human FSH. This stimulatory (FSH-like) activity increased progressively during pregnancy, with a sharp drop immediately after delivery. However, the FSH-like bioactivity was not associated with immunoreactive FSH when a specific radioimmunoassay was employed. On the other hand, serum from pregnant women caused a dose-dependent inhibition of FSH and dibutyryl-cAMP-stimulated aromatase activity. These data suggest that human pregnancy serum contains factor(s) which may stimulate basal aromatase activity of Sertoli cells and may inhibit FSH-induced aromatase activity. These factors, most probably of placental origin, may play a role in the regulation of estrogen production during gestation.

Inhibition of aromatase activity in rat Sertoli cells by thyroid hormone

1994 ◽  
Vol 140 (3) ◽  
pp. 431-436 ◽  
Author(s):  
S Ulisse ◽  
E A Jannini ◽  
E Carosa ◽  
D Piersanti ◽  
F M Graziano ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Cyclic Amp ◽  
Sertoli Cells ◽  
Inhibitory Effect ◽  
Aromatase Activity ◽  
Dependent Manner ◽  
Maximal Dose ◽  
Cyclic Amp Accumulation ◽  
Order Of Magnitude ◽  
Dose Dependent

Abstract Basal and FSH-induced aromatase activity in prepubertal rat Sertoli cells was inhibited by l-tri-iodothyronine (T3) in a time- and dose-dependent manner. The effect was evident only after 6 h of preincubation with T3 (10−7 m) and the half-maximal dose was 0·5 ±0·2 nm, which correlated with the Kd of the nuclear T3 receptor of rat Sertoli cells (Kd=1–2 nm). The effect was specific as judged by the lack of effect of the T3 analogue 3-iodo-l-thyrosine. The inhibitory effect of T3 was present over the entire range of FSH concentrations used (0·001–100 ng/ml). In T3-treated Sertoli cells, aromatase activity induced by 8-bromo-cyclic AMP was inhibited by the same order of magnitude as that of FSH, thus suggesting that the inhibitory effect of T3 was downstream from cyclic AMP formation. Furthermore, pretreatment of Sertoli cells cultures with T3 (24 h, 10−7 m) did not affect basal or FSH-induced extracellular cyclic AMP accumulation. This effect of T3 on rat Sertoli cell aromatase activity may be regarded as a part of the integrated mechanism by which thyroid hormone modulates the functions of the seminiferous epithelium. Journal of Endocrinology (1994) 140, 431–436

Inhibitory effects of alkane sulphonates on the function of immature rat Leydig, Sertoli and peritubular cells cultured in vitro

1989 ◽  
Vol 2 (2) ◽  
pp. 145-155 ◽  
Author(s):  
G. Verhoeven ◽  
J. Cailleau ◽  
I. D. Morris
Keyword(s):  
Sertoli Cells ◽  
Leydig Cells ◽  
Interstitial Cells ◽  
Aromatase Activity ◽  
Paracrine Factor ◽  
Adult Rats ◽  
Paracrine Factors ◽  
Toxic Activity ◽  
Immature Rat ◽  
Peritubular Cells

ABSTRACT Ethane 1,2-dimethane sulphonate (EDS) selectively destroys Leydig cells in the interstitium of the testis of adult rats. The toxic activity of this compound is much less obvious in the immature rat testis. We examined the effects of EDS, its monomethyl derivative and busulphan on cultured interstitial cells, percoll-purified Leydig cells, Sertoli cells and peritubular cells derived from immature rats. The studies with interstitial cells and Leydig cells showed that EDS (40–160 μg/ml) blocked the conversion of C21 and androgen precursors into testosterone and androstenedione. Higher concentrations of this compound also inhibited the production of C21 steroids and the LH-induced production of cyclic AMP (cAMP). The observed effects required a latent period of at least 8 h and were slowly reversible. Isolated cells were more sensitive to EDS than monolayer cultures. Reaggregation cultures were even less sensitive. EDS was markedly more effective on immature Leydig cells than its monomethyl derivative and busulphan. In cultured Sertoli cells FSH-inducible aromatase activity, cAMP production, androgen-binding protein (ABP) production and the secretion of a paracrine factor with Leydig cell-stimulatory activity were markedly reduced by busulphan. In these cells, busulphan was clearly more active than EDS and its monomethyl derivative. The production of paracrine factors which increase ABP production and decrease FSH-inducible aromatase activity in Sertoli cells was studied as a parameter of the effects of alkane sulphonates on peritubular cells. Only busulphan markedly decreased the production of these paracrine factors. It is concluded that EDS displays a selective toxicity to Leydig cells derived from immature animals and that, apart from its effects on germ cells, busulphan may also directly impair the function of Sertoli cells and peritubular cells.

Regulation of inhibin secretion by Sertoli cell-enriched cultures

1983 ◽  
Vol 102 (1) ◽  
pp. 136-143 ◽  
Author(s):  
G. Verhoeven ◽  
P. Franchimont
Keyword(s):  
Sertoli Cell ◽  
Sertoli Cells ◽  
Cyproterone Acetate ◽  
Aromatase Activity ◽  
Pituitary Cells ◽  
Immature Rats ◽  
Enriched Cultures ◽  
Dose Dependent ◽  
Pregnant Mare Serum Gonadotrophin ◽  
Foetal Bovine Serum

Abstract. Sertoli cells secrete a factor which has the same bioactivity as ovine testicular lymph inhibin: it selectively suppresses the secretion of FSH by cultured pituitary cells. We investigated the factors that acutely modulate the secretion of this inhibin by cultured Sertoli cells derived from immature rats. The secretion of inhibin was studied on day 7 of culture after a 24 h period of incubation in the presence or absence of steroids, gonadotrophins and foetal bovine serum, added alone or in various combinations. It could be demonstrated that aromatisable as well as non-aromatisable natural and synthetic androgens promote the secretion of inhibin in a dose-dependent way. FSH and pregnant mare serum gonadotrophin — at concentrations that clearly stimulate Sertoli cell aromatase activity — did not affect basal or androgen-stimulated production of inhibin. hCG was equally uneffective. The effect of androgens was not modified by the addition of an aromatase inhibitor but it was neutralized by the antiandrogen cyproterone acetate. Oestradiol-17β did not influence the secretion of inhibin whereas progesterone decreased it. Serum enhanced basal as well as androgen stimulated secretion of inhibin. It is concluded that androgens are the major factor which acutely stimulates the production of Sertoli cell inhibin.

Peptides PHI and VIP: comparison between vascular and nonvascular smooth muscle effect in rabbit uterus

1986 ◽  
Vol 251 (1) ◽  
pp. E48-E51 ◽  
Author(s):  
B. Bardrum ◽  
B. Ottesen ◽  
J. Fahrenkrug
Keyword(s):  
Smooth Muscle ◽  
Muscle Activity ◽  
Combined Effect ◽  
Urogenital Tract ◽  
Mechanical Activity ◽  
Response Curves ◽  
Dependent Inhibition ◽  
Dose Dependent Inhibition ◽  
Dose Dependent

The distribution and effects of the two neuropeptides, vasoactive intestinal polypeptide (VIP) and peptide histidine isoleucine amide (PHI), on vascular and nonvascular smooth muscle in the urogenital tract of nonpregnant rabbit female, were investigated. Immunoreactive VIP and PHI were present in all regions except the ovary with the highest concentration in the uterine cervix. By using in vitro tension recordings of myometrial specimens, it was demonstrated that both peptides displayed a dose-dependent inhibition of the mechanical activity. The dose-response curves of VIP and PHI were superimposable with and ID50 of 3 X 10(-8) mol/l, and their combined effect was additive. In addition, the influence of the two peptides on myometrial blood flow (MBF) was investigated by the xenon-133 washout technique. Both peptides were found to increase MBF with the same potency and efficacy. Their combined effect was additive. In conclusion VIP and PHI are present in the rabbit urogenital tract, and the two peptides are equipotent inhibitors of mechanical nonvascular and vascular smooth muscle activity in the uterus.

Follicle-stimulating hormone-dependent estrogen secretion by rat Sertoli cells in vitro: Modulation by calcium

1991 ◽  
Vol 125 (3) ◽  
pp. 280-285 ◽  
Author(s):  
J. Alan Talbot ◽  
Ann Lambert ◽  
Robert Mitchell ◽  
Marek Grabinski ◽  
David C. Anderson ◽  
...  
Keyword(s):  
Sertoli Cells ◽  
Culture Medium ◽  
Follicle Stimulating Hormone ◽  
Dibutyryl Camp ◽  
Immature Rat ◽  
Estradiol Secretion ◽  
Old Rats ◽  
Stimulating Hormone

Abstract We have investigated the role of Ca2+ in the control of FSH-induced estradiol secretion by Sertoli cells isolated from 8-10 days old rats. Exogenous Ca2+ (4-8 mmol/1) inhibited FSH-stimulated E2 secretion such that, with 8 mmol/l Ca2+ and FSH (8 IU/l) E2 secretion decreased from 2091±322 to 1480±84 pmol/l (p<0.002), whilst chelation of Ca2+ in the culture medium with EGTA (3 mmol/l) increased E2 secretion from 360±45 to 1242±133 pmol/l) in the absence of FSH. Further, EGTA (3 mmol/l) markedly potentiated FSH (8 IU/l), forskolin (1 μmol/l) and dibutyryl cAMP (1 mmol/l)-stimulated E2 secretion. Addition of the Ca2+ ionophores, ionomycin (2-5 μmol/l) and A23187 (2 μmol/l), inhibited FSH (8 IU/l)-stimulated E2 secretion by >80%. The effect of ionomycin was totally reversible, whereas that of A23187 was irreversible. Ionomycin (5 μmol/l) had no effect on EGTA-induced E2 secretion in the absence of FSH, but reduced EGTA-provoked E2 secretion by 59% in the presence of FSH (8 IU/l). Similarly, forskolin- and dibutyryl cAMP-provoked E2 production was inhibited 46-50% by ionomycin (5 μmol/l). We conclude that FSH-induced E2 secretion from immature rat Sertoli cells is modulated by intra- and extracellular Ca2+.

Differences between antigenic determinants of pig and cat zona pellucida proteins

Reproduction ◽  
2000 ◽  
pp. 15-23 ◽  
Author(s):  
K Jewgenow ◽  
M Rohleder ◽  
I Wegner
Keyword(s):  
In Vitro Fertilization ◽  
Zona Pellucida ◽  
Antigenic Determinants ◽  
Vitro Fertilization ◽  
Contraceptive Vaccine ◽  
Sperm Binding ◽  
Dependent Inhibition ◽  
Dose Dependent Inhibition ◽  
Dose Dependent

Despite many efforts, the control of reproduction in feral cat populations is still a problem in urban regions around the world. Immunocontraception is a promising approach; thus the present study examined the suitability of the widely used pig zona pellucida proteins (pZP) for contraception in feral domestic cats. Purified zona pellucida proteins obtained from pig and cat ovaries were used to produce highly specific antisera in rabbits. Antibodies against pZP raised in rabbits or lions were not effective inhibitors of either in vitro sperm binding (cat spermatozoa to cat oocytes) or in vitro fertilization in cats, whereas antibodies against feline zona pellucida proteins (fZP) raised in rabbits showed a dose-dependent inhibition of in vitro fertilization. Immunoelectrophoresis, ELISA and immunohistology of ovaries confirmed these results, showing crossreactivity of anti-fZP sera to fZP and to a lesser extent to pZP, but no interaction of anti-pZP sera with fZP. It is concluded that cat and pig zonae pellucidae express a very small number of shared antigenic determinants, making the use of pZP vaccine in cats questionable. A contraceptive vaccine based on feline zona pellucida determinants will be a better choice for the control of reproduction in feral cats if immunogenity can be achieved.

Antioxidant effects and in vitro cytotoxicity on human cancer cell lines of flavonoid-rich Flamboyant (Delonix regia (Bojer) Raf.) flower extract

2020 ◽  
Vol 21 ◽  
Author(s):  
Putthiporn Khongkaew ◽  
Phanphen Wattanaarsakit ◽  
Konstantinos I. Papadopoulos ◽  
Watcharaphong Chaemsawang
Keyword(s):  
Cell Line ◽  
Cell Lines ◽  
Cancer Cell ◽  
Leukemia Cell ◽  
Leukemia Cell Line ◽  
Flower Extract ◽  
Dependent Inhibition ◽  
Dose Dependent Inhibition ◽  
Murine Leukemia Cell ◽  
Dose Dependent

Background: Cancer is a noncommunicable disease with increasing incidence and mortality rates both worldwide and in Thailand. Its apparent lack of effective treatments is posing challenging public health issues. Introduction: Encouraging research results indicating probable anti-cancer properties of the Delonix regia flower extract (DRE) have prompted us to evaluate the feasibility of developing a type of product for future cancer prevention or treatment. Methods and Results: In the present report, using High Performance Liquid Chromatography (HPLC), we demonstrate in the DRE, the presence of high concentrations of three identifiable flavonoids, namely rutin 4.15±0.30 % w/w, isoquercitrin 3.04±0.02 %w/w, and myricetin 2.61±0.01 % w/w respectively while the IC50 of DPPH and ABTS assay antioxidation activity was 66.88±6.30 µg/ml and 53.65±7.24 µg/ml respectively. Discussion: Our cancer cell line studies using the MTT assay demonstrated DREs potent and dose dependent inhibition of murine leukemia cell line (P-388: 35.28±4.07% of cell viability remaining), as well as of human breast adenocarcinoma (MCF-7), human cervical carcinoma (HeLa), human oral cavity carcinoma (KB), and human colon carcinoma (HT-29) cell lines in that order of magnitude. Conclusion: Three identifiable flavonoids (rutin, isoquercitrin and myricetin) with high antioxidation activity and potent and dose dependent inhibition of murine leukemia cell line and five other cancer cell lines were documented in the DRE. The extract’s lack of cytotoxicity in 3 normal cell lines is a rare advantage not usually seen in current antineoplastic agents. Yet another challenge of the DRE was its low dissolution rate and long-term storage stability, issues to be resolved before a future product can be formulated.

Investigation on the antibacterial activity of electronic cigarette liquids (ECLs): a proof of concept study

2020 ◽  
Vol 21 ◽  
Author(s):  
Virginia Fuochi ◽  
Massimo Caruso ◽  
Rosalia Emma ◽  
Aldo Stivala ◽  
Riccardo Polosa ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Bacterial Species ◽  
A549 Cells ◽  
Bactericidal Effect ◽  
Minimal Bactericidal Concentration ◽  
Viability Assay ◽  
Dependent Inhibition ◽  
Dose Dependent Inhibition ◽  
Dose Dependent

Background: The key ingredients of e-cigarettes liquid are commonly propane-1,2-diol (also called propylene glycol) and propane-1,2,3-triol (vegetal glycerol) and their antimicrobial effects are already established. The nicotine and flavors which are often present in e-liquids can interfere with the growth of some microorganisms. Objective: The effect of the combining these elements in e-liquids is unknown. The aim of the study was to investigate the possible effects of these liquids on bacterial growth in the presence or absence of nicotine and flavors. Methods: Susceptibilities of pathogenic strains (Klebsiella pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, Escherichia coli, Enterococcus faecalis and Sarcina lutea) were studied by means of a multidisciplinary approach. Cell viability and antioxidant assays were also evaluated. Results: All e-liquids investigated showed antibacterial activity against at least one pathogenic strain. A higher activity was correlated to the presence of flavors and nicotine. Discussion: In most cases the value of minimal bactericidal concentration is equal to the value of minimal inhibitory concentration showing that these substances have a bactericidal effect. This effect was observed in concentrations up to 6.25% v/v. Antioxidant activity was also correlated to presence of flavors. Over time, the viability assay in human epithelial lung A549 cells showed a dose-dependent inhibition of cell growth. Conclusion: Our results have shown that flavors considerably enhance the antibacterial activity of propane-1,2-diol and propane-1,2,3-triol. This study provides important evidence that should be taken into consideration in further investigative approaches, to clarify the different sensitivity of the various bacterial species to e-liquids, including the respiratory microbiota, to highlight the possible role of flavors and nicotine.

scholarly journals In VitroActivities of Hexaazatrinaphthylenes against Leishmania spp.

2015 ◽  
Vol 59 (5) ◽  
pp. 2867-2874 ◽  
Author(s):  
Atteneri López-Arencibia ◽  
Daniel García-Velázquez ◽  
Carmen M. Martín-Navarro ◽  
Ines Sifaoui ◽  
María Reyes-Batlle ◽  
...  
Keyword(s):  
Therapeutic Agents ◽  
Content Type ◽  
Inhibition Effect ◽  
Intracellular Amastigotes ◽  
Dependent Inhibition ◽  
Leishmania Spp ◽  
Dose Dependent Inhibition ◽  
Dose Dependent ◽  
Potential Use

ABSTRACTThein vitroactivity of a novel group of compounds, hexaazatrinaphthylene derivatives, against two species ofLeishmaniais described in this study. These compounds showed a significant dose-dependent inhibition effect on the proliferation of the parasites, with 50% inhibitory concentrations (IC50s) ranging from 1.23 to 25.05 μM against the promastigote stage and 0.5 to 0.7 μM against intracellular amastigotes. Also, a cytotoxicity assay was carried out to in order to evaluate the possible toxic effects of these compounds. Moreover, different assays were performed to determine the type of cell death induced after incubation with these compounds. The obtained results highlight the potential use of hexaazatrinaphthylene derivatives againstLeishmaniaspecies, and further studies should be undertaken to establish them as novel leishmanicidal therapeutic agents.

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