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1

The role of the orphan receptor SF–1 in the development and function of the ovary

100%
Mlynarczuk J., Rekawiecki R.
Reproductive Biology
|
2010
|
tom 10
|
nr 3
2

Influence of polychlorinated biphenyls on the secretion of oxytocin from bovine luteal cells and from granulosa cells obtained from the follicles of different size

100%
Mlynarczuk J., Kotwica J.
Polish Journal of Veterinary Sciences
|
2005
|
tom 08
|
nr 4
3
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The effect of PCB126, 77, and 153 on the intracellular mobilization of Caplus 2 in bovine granulosa and luteal cells after FSH and LH surge in vitro

100%
Mlynarczuk J., Kowalik M.
Polish Journal of Veterinary Sciences
|
2013
|
tom 16
|
nr 3
Polychlorinated biphenyls (PCBs) are a group of persistent environmental pollutants that impair cattle reproduction. Among other effects, PCBs can disturb the intracellular mobilization of Ca²⁺ in several cell types. Hence, it is possible that they disrupt the transduction of intracellular signals generated from gonadotropin (FSH/LH) receptors. In steroidogenic ovarian cells, a defect in Ca²⁺ mobilization may have a detrimental influence on two important processes: the secretion of steroids (E2 or/and P4) and their morphological and functional differentiation. The aim of this study was to determine the influence of PCBs: 126 (dioxin-like) 77 (ambivalent) and 153 (estrogen-like) and a mixture of PCBs (Aroclor 1248) on these processes. Bovine granulosa and luteal cells were incubated for 72 hrs with PCBs (100 ng/ml), followed by Fura 2AM dye, and the fluctuations in intracellular Ca²⁺ mobilization after FSH/LH treatment were determined using an inverted microscope coupled with a CCD camera. The intensity and area of fluorescence excited by UV light were detected in the green spectrum of visible light. Aroclor 1248 and PCBs 153 and 77 significantly decreased (P < 0.01-0.001) the effect of FSH on intracellular Ca²⁺ mobilization in granulosa cells. In luteal cells, the most effective PCB on this process was PCB 77. The results revealed adverse effects of PCBs on the mobilization of intracellular Ca²⁺. Moreover, the estrogen-like congeners were found to more effectively disturb this process than the dioxin-like PCB 126. Hence, it is possible for PCBs to have a negative influence on reproductive processes by affecting calcium mobilization.
4

Influence of polychlorinated biphenyls on LH-stimulated secretion of progesterone and oxytocin from bovine luteal cells

100%
Mlynarczuk J., Kotwica J.
Polish Journal of Veterinary Sciences
|
2006
|
tom 09
|
nr 2
Polychlorinated biphenyls (PCBs) due to their lipophilic properties can be easily accumulated in animal and human body and elicit diverse effects causing impairment of reproductive processes. Since these compounds were not be able to affect directly the luteal steroidogenesis, the aim of the present study was to verify hypothesis that PCBs can impair the effect of LH on the secretory function of luteal cells. Bovine luteal cells from different stages of the oestrous cycle (days 1-5, 6-10, 11-15 and 16-18) were exposed for 72h to various congeners of PCBs (PCB 126, PCB 77 and PCB 153) at the doses of 1, 10 or 100 ng/ml, in the presence or absence of LH (100 ng/ml), to determine the possible effect of these compounds on progesterone (P4) and ovarian oxytocin (OT) secretion. Only PCB 77 on days 1-5 and 16-18 increased P4 secretion. All PCBs decreased LH-simulated secretion of P4 from luteal cells obtained from all days of luteal phase. Dioxin-like congener (PCB 126) inhibited (P<0.05) the most evidently LH effect on P4 secretion. All congeners, except the lower doses of PCB 126, increased (P<0.05) OT secretion. They can also increase LH-stimulated secretion of OT, but the effect was dependent on the congener used and on the phase of oestrous cycle. On days 1-5 and 10-15, PCB 126 diminished LH-stimulated effect on OT secretion from luteal cells. PCB 77 (mimickig both dioxin and estradiol effect) in the higher doses, amplified effect of LH-stimulated OT secretion, while on all other days it diminished LH influence. PCB 153, which has estrogen-like properties, amplified LH effect on OT secretion during all studied days of the cycle. We conclude that PCBs (supposedly via estrogen and arylhydrocarbon - AhR receptor) may directly affect LH-stimulated function of CL. This does not appear to be a direct adverse effect on luteal steroidogenesis, but rather indirect on OT secretion from or within CL.
5
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The protein expression disorders of connexins (Cx26, Cx32 and Cx43) and keratin 8 in bovine placenta under the influence of DDT, DDE and PCBs

81%
Wojciechowska A., Mlynarczuk J., Kotwica J.
Polish Journal of Veterinary Sciences
|
2018
|
tom 21
|
nr 4
6

Wplyw DDT i jego metabolitow na czynnosc sekrecyjna komorek lutealnych, granulozy i endometrium krowy

81%
Wrobel M., Mlynarczuk J., Kotwica J.
Medycyna Weterynaryjna
|
2008
|
tom 64
|
nr 04B
583-587
Dichlorodiphenyltrichloroethane (DDT) is a persistent insecticide, recognized as an environmental pollutant. Due to its lipophilic properties, DDT and its metabolite (DDE) are accumulated in tissues of farm animals. The aim of the study was to examine the influence of DDT and DDE on estradiol, progesterone and oxytocin secretion from the ovary and on prostaglandin (F2α and E2) secretion from the uterus, was investigated. Granulosa, luteal and endometrial cells from cows at 8-12 days of the estrous cycle were treated for 24-72 h with 0.1-10 ng/ml of DDT, p,p’-DDE, o,p’-DDE or with a technical mixture of DDE isomers. Neither DDT nor DDE were found to affect the viability of cells compared to the control. They also did not affect the secretion of estradiol from granulosa cells. The utilized pollutants increased (P < 0.05-0.001) the progesterone and oxytocin secretion from luteal and granulosa cells. They also stimulated (P < 0.05) PGF2á secretion but simultaneously reduced (P < 0.001) PGE2 secretion from endometrial cells. Hence the ratio of PGF2α to PGE2 was markedly changed, from 1:1 in the control, up to 1:4-10 in treated cells. It has been concluded that DDT and its metabolites may impair regulation of the estrous cycle in cows by stimulation of oxytocin secretion from luteal and granulosa cells and by stimulation of PGF2α and the simultaneous inhibition of PGE2 secretion from endometrial cells.
7

Mechanizm wplywu progesteronu na wlasna synteze w cialku zoltym

81%
Kotwica J., Duras M., Rekawiecki R., Mlynarczuk J.
Działalność Naukowa PAN. Wybrane Zagadnienia
|
2004
|
tom 18
110-111
8

Short-term incubation of bovine placentome sections as a tool to study xenobiotic mechanism of action

81%
Wojciechowska A., Mlynarczuk J., Kotwica J.
Reproductive Biology
|
2015
|
tom 15
|
nr 4
9

Ekspresja genow dla NP-I-OT i PGA w komorkach lutealnych i warstwy ziarnistej pecherzyka jajnikowego oraz czynnika LIF w komorkach endometrium krowy pod wplywem DDT i jego metabolitow

81%
Mlynarczuk J., Wrobel M., Kotwica J.
Medycyna Weterynaryjna
|
2008
|
tom 64
|
nr 04B
579-582
Ovarian oxytocin (OT) and endometrial leukemia inhibitory factor (LIF) are involved in estrous cycle regulation and implantation of the blastocyst in cows. For this reason the authors investigated the effect of DDT and its metabolites (DDE), known as environmental pollutants, on the expression of genes involved in OT and LIF synthesis. Granulosa from follicles (1 cm in diameter), luteal and endometrial cells from cows on days 8-12 of the estrous cycle were treated for 6 h with DDT, p,p’-DDE, o,p’-DDE and technical mixture (MIX) of DDE isomers (10 ng/ml each). Obtained RNA was reverse transcribed and cDNA was amplified by PCR using primers for genes of NP-I/OT, PGA, LIF and G3PDH as a reference gene. DDT and DDE in granulosa cells and DDE in luteal cells increased (P < 0.05) the expression of the NP-I/OT gene, while DDE in granulosa cells and MIX in luteal cells increased the expression of the PGA gene (P < 0.05). In contrast, p,p’-DDE and MIX reduced (P < 0.05) the LIF expression in endometrial cells. Obtained data allow the authors to assume that DDE and its metabolite impairs regulation of the estrous cycle, affecting OT and LIF synthesis on the genomic level.
10
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The effect of DDE and dieldrin and their parental substances (DDT and aldrin) on PGE2 and PGF2α release from bovine endometrial explants collected during 120 to 180 days of the gestational period

81%
Mlynarczuk J., Wrobel M. H., Dobrzyn K.
Polish Journal of Veterinary Sciences
|
2021
|
tom 24
|
nr 1
11
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Effect of cortisol on neurophysin I/oxytocin and peptidyl glycine-α-amidating mono-oxygenase mRNA expression in bovine luteal and granulosa cells

81%
Ziolkowska A., Mlynarczuk J., Kotwica J.
Polish Journal of Veterinary Sciences
|
2013
|
tom 16
|
nr 2
Cortisol stimulates the synthesis and secretion of oxytocin (OT) from bovine granulosa and luteal cells, but the molecular mechanisms of cortisol action remain unknown. In this study, granulosa cells or luteal cells from days 1-5 and 11-15 of the oestrous cycle were incubated for 4 or 8 h with cortisol (1x10⁻⁵, 1x10⁻⁷ M). After testing cell viability and hormone secretion (OT, progesterone, estradiol), we studied the effect of cortisol on mRNA expression for precursor of OT (NP-I/OT) and peptidyl glycine-α-amidating mono-oxygenase (PGA). The influence of RU 486 (1x10⁻⁵ M), a progesterone receptor blocker and inhibitor of the glucocorticosteroid receptor (GR), on the expression for both genes was tested. Cortisol increased the mRNA expression for NP-I/OT and PGA in granulosa cells and stimulated the expression for NP-I/OT mRNA in luteal cells obtained from days 1-5 and days 11-15 of the oestrous cycle. Expression for PGA mRNA was increased only in luteal cells from days 11-15 of the oestrous cycle. In addition, RU 486 blocked the cortisol-stimulated mRNA expression for NP-I/OT and PGA in both types of cells. These data suggest that cortisol affects OT synthesis and secretion in bovine ovarian cells, by acting on the expression of key genes, that may impair ovary function.
12

Relationship between progesterone and ovarian oxytocin within corpus luteum in cow

80%
Kotwica J., Mlynarczuk J., Duras M., Amarowicz M.
Bulletin of the Veterinary Institute in Puławy
|
2003
|
tom 47
|
nr 2
13

The influence of polychlorinated biphenyls [PCBs] and phytoestrogens in vitro on functioning of reproductive tract in cow

80%
Kotwica J., Wrobel M., Mlynarczuk J.
Reproductive Biology
|
2006
|
tom 06
|
nr Suppl.1
14

Non-genomic action of progesterone in cultured bovine luteal and endometrial epithelial cells

80%
Mlynarczuk J., Sasiadek J., Kotwica J.
Bulletin of the Veterinary Institute in Puławy
|
2005
|
tom 49
|
nr 2
15
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Sex-dependent differences in the effect of early weaning on the chosen hormones secretion in sheep during the postnatal transition to puberty – Preliminary results

71%
Cieslak, Chmielewska N., Romanowicz K., Mlynarczuk J., Wankowska M.
Polish Journal of Veterinary Sciences
|
2015
|
tom 18
|
nr 1
The influence of early weaning on the cortisol, follicle-stimulating hormone (FSH), luteinizing hormone (LH) and growth hormone (GH) secretion in lambs of both sexes and testosterone (T4) level in male lambs during the postnatal transition to puberty was investigated by radioimmunoassay. It was hypothesized that this influence is long-term and sexually dimorphic. Hence, the effect of weaning at 5 weeks of age in comparison with the weaning at 9 weeks of age on hormone concentrations in peripheral blood plasma of 5-, 9-, 12-, and 16-week-old lambs of both sexes was investigated. The cortisol concentrations were greater (P<0.05) in control and early weaned female lambs than in male lambs at investigated stages. Weaning at 5 weeks of age resulted in the lover (P<0.05) cortisol secretion in male lambs in contrast to the greater (P<0.05) cortisol secretion in female lambs at 16 weeks of age. Weaning at 5 weeks of age stimulated (P<0.001) the FSH secretion, but reduced (P<0.001) the LH, GH and T4 secretion in 16-week-old male lambs. In female lambs early weaning inhibited (P<0.05) the FSH secretion at 9 weeks of age, LH secretion after 9 weeks of age and GH secretion after 12 weeks of age. Thus, early weaning results in the sexually dimorphic stress reaction that is more potent and long-lasting in female in contrast to male lambs. This maternal deprivation stress contributes to the inhibition of LH and GH secretion in lambs of both sexes and T4 secretion in male lambs during the postnatal transition to puberty.
16
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Effect of a two-week treatment with low dose of ortho-substituted polychlorinated biphenyls (PCB104 and PCB153) on VEGF-receptor system expression in the choroid plexus in adult ewes

61%
Szczepkowska A., Mlynarczuk J., Grochowalski A., Dufourny L., Thiery J.-C., Skipor J.
Polish Journal of Veterinary Sciences
|
2012
|
tom 15
|
nr 4
Ortho-substituted polychlorinated biphenyl (PCB) congeners, which constitute a large part of PCB residues found in the environment and in animal tissues, are known to exert potent vascular effects and can activate endothelial cells in the periphery and in the brain. The choroid plexus (CP) is responsible for cerebrospinal fluid (CSF) production and its epithelial cell layer is responsible for structure and functions of the blood-CSF barrier. The aims of this study were: 1) to investigate if environmentally relevant doses of PCB153 and similar doses of PCB104 caused changes in the expression of vascular endothelial growth factor (VEGF) - receptor system, which maintains CP function, and 2) to determine the level of both congeners in blood plasma after their oral administration. Studies of both congeners were performed on ovariectomized ewes treated per os with low doses (0.1 mg/kg, three times a week for two weeks) of PCB153 (n=4) or PCB104 (n=4) and vehicle (control, n=4). The effects of PCB153 and PCB104 treatment on mRNA expression of two isoforms of VEGF (VEGF120 and VEGF164) and their receptors Flt-1 and KDR were determined using real-time PCR. Plasma concentration of PCBs was measured using high resolution chromatography/tandem mass spectrometry (HRGC/MS-MS). We observed that neither PCB153 nor PCB104 significantly altered the mRNA of the VEGF-receptor system in the CP. In PCB treated animals plasma concentration of PCB153 (1.425 ± 0.16 ng/g of dry mass, DM) was about 150 times higher than PCB104 (0.009 ± 0.007ng/g DM). In control animals the PCB153 level was 0.14 ± 0.031 ng/g DM, while the PCB104 level was below detection level. This indicates that increase in plasma PCB153 concentration to levels similar to those reported in humans and of PCB104 concentration to levels 100 times higher than those found in human plasma did not affect the VEGF-receptor system in the CP in adult ewes. The significantly lower increase of PCB104 than PCB153 concentration in blood after oral administration suggests different absorption of both congeners from the digestive tract.
17

Preliminary evaluation of influence of zearalenone on cocultures of granulosa and internal theca cells of ovarian follicles in bitches in in vitro culture

61%
Skorska-Wyszynska E., Jakimiuk E., Gajecka M., Mlynarczuk J., Obremski K., Gajecki M.
Polish Journal of Veterinary Sciences
|
2004
|
tom 07
|
nr 4
Zearalenone (ZEA) is an undesirable substance in feed materials and feed of plant origin. It is an example of the micotoxin that causes disturbances in the functioning of the reproductive system. The wide range of plant compounds in pet food means that ZEA may frequently have a negative effect on pet reproduction. An assessment of the influence of ZEA on the granulosa and theca cells of the ovarian follicle in bitches in vitro was carried out. The co-culture of the ovarian follicles was incubated for 72 hours with the addition of 12.5 ng/ml and 25.0 ng/ml of ZEA. Numerous vacuoles in the cytoplasm of the granulosa cells were noted in the culture with the addition of 25.0 ng/ml of ZEA. Preliminary investigations suggest negative effect of ZEA on the granulosa cells in bitches in vitro.
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