170 research outputs found
Individual and combined effects of deoxynivalenol and zearalenone on bovine granulosa cell proliferation
No full textDeoxynivalenol (DON) and Zearalenone (ZEA) are fusariotoxins frequently found together in commodities used as animal feed. The estrogenic effects of ZEA in all species are well established whereas the effects of DON on the reproductive system are unclear. The purpose of this study is to evaluate the in vitro effects of DON and α-Zearalenol (α-ZEA) on cell proliferation by using bovine granulosa cells (GC). Ovaries from non-pregnant beef cows were collected from a nearby slaughterhouse and large granulosa cells (LGGC) were obtained by aseptically aspirating ovarian follicles (8-22 mm) with an 18-gauge needle. Cells were cultured for 2 days in 5% fetal bovine serum-containing medium followed by 2 days in serum-free medium containing control or mycotoxin treatments. At the end of the experiment, cell numbers were determined using a Coulter counter. The effects of DON and α-ZEA were tested using various dosages (0.1, 0.33, 3.3 μM and 0.09, 0.31, 3.1 μM respectively) and a concomitant treatment with DON at 0.1 μM and α-ZEA at 0.09 μM respectively was also carried out. DON at 3.3 μM decreased cell proliferation whereas the other two treatments with DON had no significant effects. After exposure to α-ZEA, LGGC proliferation was increased by the lowest concentration tested (0.09 μM) while the highest one (3.1 μM) had no effect compared to the control. The combination of these mycotoxins strongly affected LGCC cell growth, increasing cell numbers. The results demonstrate that DON affects cell proliferation mainly at high dosage by decreasing LGGC numbers while α-ZEA can impact cell numbers more at the lowest dosage causing cell proliferation growth. Finally a synergic effect was observed when the mycotoxins are combined. Further studies are in progress to better understand the mechanism of the effects of DON and ZEA on GC
Individual and combined effects of deoxynivalenol and zearalenone on steroidogenesis in bovine granulosa cells
No full textZearalenone (ZEA), a phyto-estrogenic molecule, and Deoxynivalenol (DON) are mycotoxins produced by Fusarium spp. and found to co-exist in commodities. Reproductive effects caused by ZEA in ruminants have been reported, while direct effects on fertility related to DON are unknown. The aim of this study is to evaluate steroidogenesis effects of DON and α-Zearalenol (α-ZEA), the hydroxilated metabolite, on bovine granulosa cells (GC). Briefly, small bovine granulosa cells (SMGC) from ovarian follicles (1–5 mm) were cultured at 2.5 x 105 cells/well for 2 days in 5% fetal bovine serum-containing medium followed by 2 days in serum-free medium containing control (no additions) or mycotoxin treatments. Concentrations of progesterone and estradiol in cell culture medium were determined using radioimmunoassay (RIA). DON and α-ZEA were tested at 0.1, 0.33, 3.3 μM and 0.09, 0.31, 3.1 μM respectively and the effects of a combination of the two mycotoxins, at 0.1 μM (DON) and at 0.09 μM (α-ZEA), were also evaluated. Progesterone production was dramatically reduced only after exposure to DON at the highest concentration (3.3 μM) while estradiol production decreased after exposure to all DON and α-ZEA dosages, showing the biggest change after exposure to DON at 3.3 μM. The concomitant treatment with 0.1 μM DON and 0.09 μM α-ZEA respectively showed a synergic inhibitory effect on estradiol production. In conclusion, DON can affect steroidogenesis in bovine SMGC more than α-ZEA , mainly after it has been introduced at high dosages or in combination
In vitro effects of deoxynivalenol and β-Zearalenol alone and in combination on steroidogenesis in bovine small granulosa cells
No full textIn vitro effects of zearalenone metabolites on cell proliferation and steroidogenesis with bovine granulosa cells
No full textZearalenone (ZEA), an oestrogenic fusariotoxin common contaminant of feedstuffs,
is rapidly metabolized in rumen into α-Zearalenol (α-ZEA) and to a lower amount
β-Zearalenol (β-ZEA). The purpose of this study is to evaluate the in vitro effects of
α-ZEA and β-ZEA on cell proliferation and steroidogenesis by using bovine granulosa
cells (GC). Ovaries were collected from a nearby slaughterhouse and small granulosa
cells (SMGC) were obtained by aspirating ovarian follicles (1-5 mm). Cells were cultured
for 2 days in 10% fetal bovine serum-containing medium followed by 2 days in serumfree
medium containing control or mycotoxin treatments. Cell numbers were determined
using a Coulter counter while concentrations of progesterone (P4) and estradiol (E2) in
cell culture medium were determined using radioimmunoassay. α-ZEA and β-ZEA were
tested at 0.31 μM and at 0.31, 3.1, 31 μM, respectively. A co-exposure to α-ZEA and
β-ZEA at 0.31 μM each was also carried out. All experiments were performed with and
without IGF1. Cell proliferation was inhibited in presence of IGF1 at 3.1 and 31 μM of
β-ZEA while without IGF1 only at 31 μM of β-ZEA was inhibitory. A synergic inhibitory
effect on cell proliferation and E2 production was demonstrated after co-exposure to
α-ZEA and β-ZEA only in cells treated with IGF1. Without IGF1, E2 production was
strongly stimulated at 31 μM compared to the control whereas in presence of IGF1 E2
release was inhibited (by 40%) by β-ZEA at 3.1 μM. P4 production was stimulated after
exposure to β-ZEA at the highest dose tested (31 μM) in presence and absence of IGF1.
Further studies are in progress to better understand the mechanism of action of ZEA and
its metabolites on GC
The role of endothelins in regulating bovine granulosa cells steroidogenesis
No full textEndothelins are a group of vasoactive 21 amino acid peptides reported to play roles in steroidogenesis, folliculogenesis, and ovulation (Bridges et al. 2012 Life Sci. 91, 501–506). Nevertheless, the role of endothelins in regulating steroidogenesis in the bovine species requires further investigation. Thus, the objective of this study was to investigate the effects of endothelin 1 (ET-1) and endothelin 2 (ET-2) on bovine granulosa cell (GC) steroidogenesis. Bovine ovaries were obtained from a local abattoir. Follicular fluid was aspirated from small (1–5 mm) follicles and GC were isolated and exposed to various treatments (ET-1, ET-2, or ET-1 plus ET-2 with FSH and with or without insulin-like growth factor-1). In replicated experiments, culture medium was removed and analysed for steroid production via radioimmunoassay. Granulosa cells were either harvested with trypsin and counted using a Coulter Counter or collected with Trizol for RNA extraction and quantification via real-time PCR (18S rRNA was used as a housekeeping gene). Steroid production was expressed as nanograms (in the case of progesterone) and picograms (in the case of oestradiol) per 105 cells per 24 h. Relative quantity of target gene mRNA was expressed as 2–ΔΔCt using the relative comparative threshold cycle (Ct) method. Data were analysed via ANOVA and the general linear models (GLM) procedure of SAS for Windows (SAS Institute Inc., Cary, NC). If a significant main effect was identified, differences among means were determined by Fisher’s protected least significant differences test. The values were reported as least squares means ± standard error of the mean. In the presence of insulin-like growth factor-1, ET-1 significantly inhibited oestradiol production at 300 ng mL–1 (100.30 ± 11.05; P 0.05) in comparison to the control (141.21 ± 11.05), whereas no differences were observed for progesterone production at 300 ng mL–1 (60.11 ± 7.11; P > 0.05) or at 30 ng mL–1 (64.02 ± 7.11; P > 0.05) in comparison to control (76.75 ± 7.11). ET-2 also significantly inhibited oestradiol production at 300 ng mL–1 (91.08 ± 11.87; P 0.05) in comparison to the control in the presence of insulin-like growth factor-1. No significant effect of ET-1 and ET-2 was observed on steroidogenesis of granulosa cells cultured without insulin-like growth factor-1. Consistent with steroids production data, real-time PCR results indicated that, in the presence of IGF-1, ET-1 (5.66 ± 1.05) and ET-2 (5.65 ± 1.05) inhibited (P 0.05), ET-2 (5.94 ± 0.95; P > 0.05), or ET-1 plus ET-2 (4.57 ± 0.95; P > 0.05) was observed for side-chain cleavage enzyme (CYP11A1) in comparison to controls (4.4 ± 1.07). Altogether, these results indicate that endothelins are involved in the regulation of steroidogenesis of bovine GC
The in vitro effects of Fusarium mycotoxins on bovine granulosa cell CYP11A1 and CYP19A1 mRNA
No full textDirect effects of the algal toxin, domoic acid, on ovarian function : bovine granulosa and theca cells as an in vitro model
No full textDomoic acid (DA) is a potent neurotoxin produced by alga Pseudo-nitzschia spp. and has been associated with reproductive disorders in mammals. The aim of this study was to investigate if DA can affect the reproductive system via direct action on ovarian function. Bovine granulosa and theca cells were used as in vitro models for evaluating DA effects on ovarian cell proliferation and steroid production. In small-follicle granulosa cells (SMGC), cell proliferation and estradiol (E2) production was not affected (P>0.05) while progesterone (P4) production was inhibited (P0.05) on cell proliferation or P4 production while E2 production was stimulated by 1 and 5μg/ml DA (P0.10) on E2 production. Collectively, these results show for the first time that DA has direct effects on ovarian GC and TC steroidogenesis. Because DA inhibited E2 and P4 production, DA has the potential to be an endocrine disruptor
Individual and combined effects of deoxynivalenol and α-zearalenol on cell proliferation and steroidogenesis of granulosa cells in cattle
No full textThis study was conducted to evaluate the impact of deoxynivalenol (DON) and zearalenone (ZEA) metabolite, α-zearalenol (α-Zol), on cell proliferation and steroidogenesis of bovine large (LG) follicle granulosa cells (GC). LGGC were obtained from bovine ovarian follicles (8-22 mm) and were cultured for 2 days in medium containing 10% fetal bovine serum followed by 1 or 2 days in serum-free medium without (control) or with treatments. Three different experiments were performed using different dosages of DON and α-Zol and in different combinations and a fourth experiment evaluated estradiol effects on granulosa cell proliferation. DON inhibited progesterone (P4) and estradiol (E2) production at high dose. α-Zol alone and in combination with DON increased cell growth. Estradiol inhibited cell growth indicating α-Zol is not acting as an estrogen agonist. This study demonstrates that α-Zol and DON can impact in vitro GC function, however further studies will be required to better understand the mechanism of action and reproductive effects of Fusarium mycotoxins
waps
No full textwop1 n... we find the letters transposed ... in ... "waps" for wasp and "wordle" for world.YesPRINTED ITEM APR 1975 G. M. StoryJH APR 1975Used I and SupUsed I and Sup1Not usedwap, wapse, wops, waps, wap totty, wepsk, wopse
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