The aim of this in vitro study was to examine the release of progesterone by porcine ovarian granulosa cells (GCs) after exposure to toxic concentrations of deoxynivalenol (DON), resveratrol (RSV), and their combination (DON with RSV). Ovarian granulosa cells were incubated without (control) or with treatments of natural substances at various doses for 24 h: RSV (10, 30 and 50 μg/mL) / DON (2000, 3000 and 5000 ng/mL), and their combination (10 μg/mL of RSV with 2000 ng/mL of DON; 30 μg/mL of RSV with 3000 ng/mL of DON; 50 μg/mL of RSV with 5000 ng/mL of DON). Progesterone was determined by radioimmunoassay (RIA). Progesterone release was significantly (P < 0.05) stimulated by RSV at the doses 50 μg/mL but not at 30 and 10 μg/mL and by DON treatment at all used doses (2000, 3000 and 5000 ng/mL). RSV in combination with DON stimulated significantly (P < 0.05) the progesterone release by GCs at the highest doses (50 μg/mL of RSV with 5000 ng/mL of DON). On the other hand, the stimulatory effect of RSV in combination with DON was significantly (P < 0.05) lower in comparison with alone DON effect. In conclusion, our results indicate, (1) the dose-depended stimulatory effects of RSV, DON and combination of RSV with DON on release of steroid hormone progesterone and (2) reduction of the stimulatory effect of DON by RSV. Our in vitro results suggest that reproductive toxicity of animals induced by a mycotoxin - deoxynivalenol can be inhibited by a protective natural substance – resveratrol.

Recent studies documented that the selective estrogen receptor modulator tamoxifen prevents follicle loss and promotes fertility following in vivo ex

Previously, we reported that administration of prolactin (PRL) during the early luteal phase in sows increases plasma progesterone concentrations. In the current study, we searched for the mechanisms by which PRL exerts this luteotrophic effect. The objectives of the study were (1) to examine the effect of PRL and/or low-density lipoproteins (LDL) on progesterone production by porcine luteal cells derived from early corpora lutea, and (2) to assess the ability of PRL to activate phosphoinositide-specific phospholipase C (PI-PLC) and protein kinase C (PKC) in these luteal cells. Ovaries with early corpora lutea (day 1-2 of the oestrous cycle) were obtained from the slaughterhouse. Progesterone production by dispersed luteal cells was measured after treatment with PRL, phorbol 12-myristate 13-acetate or inhibitors of PKC in the presence or absence of LDL. LDL increased progesterone concentration in the incubation medium (304.5 vs 178.6 ng/ml in control, P<0.05). PRL augmented LDL-stimulated progesterone secretion by luteal cells (to 416 ng/ml, P0.05). Staurosporine, a PKC inhibitor, inhibited progesterone secretion stimulated by the combined action of LDL and PRL; however, such inhibition was not demonstrated when cells were treated with the PKC inhibitor, H-7. PKC activation was assessed by measuring the specific association of [H]phorbol dibutyrate (H-PDBu) with luteal cells after treatment with PRL or ionomycin (a positive control). PRL and ionomycin increased H-PDBu-specific binding in early luteal cells by 28+/-5.5% (within 5 min) and 70.2+/-19.3% (within 2 min) over control binding respectively (P<0.05). In addition, PRL did not augment the LDL-stimulated progesterone production in PKC-deficient cells. In contrast with PKC, total inositol phosphate accumulation, as well as intracellular free calcium concentrations, were not affected by PRL in the current study. We conclude that PRL, in the presence of LDL, stimulates progesterone production by early corpora lutea in vitro. Moreover, PRL appears to activate PKC, but not PI-PLC, in these cells. Thus intracellular transduction of the PRL signal may involve activation of PKC that is not dependent on PI-PLC.

Long non-coding RNAs (lncRNAs) may regulate gene expression in numerous biological processes including cellular response to xenobiotics. The exposure of living organisms to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a persistent environmental contaminant, results in reproductive defects in many species including pigs. The aims of the study were to identify and characterize lncRNAs in porcine granulosa cells as well as to examine the effects of TCDD on the lncRNA expression profile in the cells. One thousand six hundred sixty-six lncRNAs were identified and characterized in porcine granulosa cells. The identified lncRNAs were found to be shorter than mRNAs. In addition, the number of exons was lower in lncRNAs than in mRNAs and their exons were longer. TCDD affected the expression of 22 lncRNAs (differentially expressed lncRNAs [DELs]; log₂ fold change ≥ 1, P-adjusted < 0.05) in the examined cells. Potential functions of DELs were indirectly predicted via searching their target cis- and trans-regulated protein-coding genes. The co-expression analysis revealed that DELs may influence the expression of numerous genes, including those involved in cellular response to xenobiotics, dioxin metabolism, endoplasmic reticulum stress and cell proliferation. Aryl hydrocarbon receptor (AhR) and cytochrome P450 1A1 (CYP1A1) were found among the trans-regulated genes. These findings indicate that the identified lncRNAs may constitute a part of the regulatory mechanism of TCDD action in granulosa cells. To our knowledge, this is the first study describing lncRNAs in porcine granulosa cells as well as TCDD effects on the lncRNA expression profile. These results may trigger new research directions leading to better understanding of molecular processes induced by xenobiotics in the ovary.