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Sirotkin A.V.,Research Institute of Animal Production | Sirotkin A.V.,Constantine the Philosopher University | Sirotkin A.V.,King Saud University | Sirotkin A.V.,Animal Production Research Center Nitra | And 6 more authors.
Functional and Integrative Genomics | Year: 2015

MicroRNAs (miRNAs) are known to influence ovarian cell proliferation, apoptosis and hormone release, but it remains unknown whether miRNAs affect ovarian functions via transcription factors. We examined the effect of miRNAs on nuclear factor-κappaB (NF-kB) (p65) expression in human ovarian luteinized granulosa cells. We transfected cultured primary human ovarian luteinized granulosa cells with 80 different constructs encoding human pre-miRNAs and then evaluated NF-kB (p65) expression (percentage of cells containing p65) by immunocytochemistry. We found that 21 of the constructs stimulated NF-kB (p65) expression and 18 of the constructs inhibited NF-kB (p65) expression. This is the first direct demonstration that miRNAs affect NF-kB (p65) expression and the first genome-scale miRNA screen to identify upregulation and downregulation of NF-kB accumulation by miRNAs in the ovary. Novel miRNAs that affect the NF-kB signalling pathway could be useful for the control of NF-kB-dependent reproductive processes and the treatment of NF-kB-dependent reproductive disorders. © 2014, Springer-Verlag Berlin Heidelberg.

Varadyova Z.,Slovak Academy of Sciences | Jalc D.,Slovak Academy of Sciences | Laukova A.,Slovak Academy of Sciences | Mihalikova K.,Slovak Academy of Sciences | Homolka P.,Research Institute of Animal Production
Turkish Journal of Agriculture and Forestry | Year: 2013

Survival of inoculants in grass silages may enable them to improve the quality of silages through enrichment with polyunsaturated fatty acids (PUFAs). The effects of 2 inoculants, Enterococcus faecium 2/3s (EF2/3s) and E. faecium 26/42 (EF26/42), on nutrient composition, fermentation parameters, and fatty acid content in grass silages during ensiling (111 days) of fresh grass (G) were examined under laboratory conditions. The G [285 g of dry matter (DM) kg-1] was ensiled in 36 polyethylene jars (1 L) divided into 3 × 12 sets per treatment and ensiled at 21 °C for 111 days. The 3 silage treatments used were: 1) grass without inoculant (GS, control), 2) grass inoculated by the strain EF2/3s (GS+EF2/3s), and 3) grass inoculated by the strain EF26/42 (GS+EF26/42). The inoculant strains were sufficiently established during ensiling and reached 4.62 log10 cfu g-1 for EF2/3s and 3.76 log10 cfu g-1 for EF26/42 on day 111 of ensiling. Crude protein contents were G > GS+EF2/3s > GS+EF26/42 > GS (129, 110, 109, and 100 g kg-1 of DM, respectively). The lactate-to-acetate ratios were GS < GS+EF26/42 < GS+EF2/3s (2.82, 4.20, and 4.70, respectively). Concentrations of α-linolenic acid and γ-linolenic acid were highest in grass before ensiling (P < 0.001). Higher isomer C18:2 (9,11) content (P < 0.01) was detected in GS+EF2/3s and GS+EF26/42 than in GS. Nutritional manipulation associated with Enterococcus faecium EF2/3s and EF26/42 inoculation of GS resulted in better quality of silages based on lower lactate (GS+EF26/42) and a greater lactic-to-acetic acid ratio (GS+EF2/3s and GS+EF26/42). This might positively affect PUFAs and their isomers. © TÜBİTAK.

Novotna B.,Academy of Sciences of the Czech Republic | Petr J.,Research Institute of Animal Production | Sedmikova M.,Czech University of Life Sciences | Kratochvilova J.,Czech University of Life Sciences | Jilek F.,Czech University of Life Sciences
Zygote | Year: 2010

The effect of different activation protocols on DNA integrity of porcine oocytes matured in vitro was analysed using the comet assay. The oocytes from ovaries of slaughtered gilts were cultured for 48 h in modified M199 medium. They were then freed of cumulus cells and treated continuously or intermittently with a nitric oxide (NO) donor for 6 h. Standard activation with calcium ions (Ca2+) and culture without any treatment served as positive and negative controls, respectively. The activation was assessed according to the formation of pronuclei. Exposure of oocytes to Ca2+ was associated with high activation efficiency, but decreased DNA integrity. The opposite, i.e. low activation efficiency but high DNA integrity was observed after continuous exposure to NO. Intermittent action of NO increased the activation rate, while the values of DNA damage remained at low levels. Our data suggest that an increased DNA instability could be the main reason compromising the further embryonic development of oocytes activated by the standard protocol. The intermittent treatment with NO thus represents a promising step to optimization of parthenogenetic activation of pig oocytes. © 2009 Cambridge University Press.

Kuzinski J.,Research Institute for the Biology of Farm Animals FBN | Zitnan R.,Research Institute of Animal Production | Warnke-Gurge C.,Research Institute for the Biology of Farm Animals FBN | Warnke-Gurge C.,University of Rostock | Schweigel M.,Research Institute for the Biology of Farm Animals FBN
Journal of Biomedicine and Biotechnology | Year: 2010

In this study, the effect of metabolic inhibition (MI) by glucose substitution with 2-deoxyglucose (2-DOG) and/or application of antimycin A on ovine rumen epithelial cells (REC) vacuolar-type H +-ATPase (vH +-ATPase) activity was investigated. Using fluorescent spectroscopy, basal pH i of REC was measured to be 7.3 ± 0.1 in HCO 3 --free, glucose-containing NaCl medium. MI induced a strong pH i reduction (-0.44 ± 0.04 pH units) with a more pronounced effect of 2-DOG compared to antimycin A (-0.30 ± 0.03 versus-0.21 ± 0.03 pH units). Treatment with foliomycin, a specific vH +-ATPase inhibitor, decreased REC pH i by 0.21±0.05 pH units. AfterMI induction, this effect was nearly abolished (-0.03±0.02 pH units). In addition, membrane-associated localization of vH +-ATPase B subunit disappeared. Metabolic control of vH +-ATPase involving regulation of its assembly state by elements of the glycolytic pathway could provide a means to adapt REC ATP consumption according to energy availability. Copyright © 2010 Judith Kuzinski et al.

Sirotkin A.V.,Constantine the Philosopher University | Sirotkin A.V.,Research Institute of Animal Production | Mertin D.,Research Institute of Animal Production | Vegova K.S.,Research Institute of Animal Production | And 2 more authors.
Biology Open | Year: 2016

The aim of our study was to understand whether ovarian steroid hormones, and their response to the metabolic hormones leptin and IGF-I leptin, could be involved in the control of mink reproductive aging via changes in basal release of ovarian progesterone and estradiol. For this purpose, we compared the release of progesterone and estradiol by ovarian fragments isolated from young (yearlings) and old (3-5 years of age) minks cultured with and without leptin and IGF-I (0, 1, 10 or 100 ng/ml). We observed that isolated ovaries of older animals produced less progesterone but not less estradiol than the ovaries of young animals. Leptin addition stimulated estradiol release by the ovarian tissue of young animals but inhibited it in older females. Leptin did not influence progesterone output by the ovaries of either young or older animals. IGF-I inhibited estradiol output in young but not old animals, whereas progesterone release was inhibited by IGF-I irrespective of the animal age. Our observations demonstrate the involvement of both leptin and IGF-I in the control of mink ovarian steroid hormones release. Furthermore, our findings suggest that reproductive aging in minks can be due to (a) reduction in basal progesterone release and (b) alterations in the response of estradiol but not of progesterone to leptin and IGF-I. © 2016. Published by The Company of Biologists Ltd.

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