K. Lukasik - Academia.edu (original) (raw)
Papers by K. Lukasik
Animal - science proceedings
Animal - science proceedings
Journal of Equine Veterinary Science, 2018
Animal - science proceedings
ABSTRACT Background / Purpose: The interactions between luteal, vascular endothelial, immune cell... more ABSTRACT Background / Purpose: The interactions between luteal, vascular endothelial, immune cells and its products: steroids, peptide hormones, prostaglandins (PGs), growth factors and cytokines play a pivotal role in the regulation of corpus luteum (CL) function. Luteal endothelial cells undergo many dynamic morphological changes and their action is regulated by cytokines.To establish an in vitro model for bovine luteal endothelial cells examination. To study the effect of cytokines: tumor necrosis factor α (TNF) and interferon γ (IFN) on cell viability, leukotrienes (LTs) and PG synthases, and endothelin-1 (EDN-1) mRNA, protein expression and their secretion in bovine immortalized luteal endothelial (EnCL-1) cells. Main conclusion: EDN-1, PGs and LTs are produced and secreted by immortalized BEC showing proper secretory function of immortalized BEC. Immortalized BEC are sensitive on TNF action and this cytokine modulates expressions for enzymes responsible for production of AA metabolites and its levels.
Theriogenology, 2019
Transforming growth factor (TGF)-β1 not only regulates cell growth, development, and tissue remod... more Transforming growth factor (TGF)-β1 not only regulates cell growth, development, and tissue remodeling, but it also participates in the pathogenesis of tissue fibrosis. In the equine endometrium, the concentration of TGF-β1 is correlated with endometrosis (equine endometrial fibrosis). In other tissues, TGF-β1 induces differentiation of many cell types into myofibroblasts. These cells are characterized by α-smooth muscle actin (α-SMA) expression and an ability to deposit excessive amounts of extracellular matrix (ECM) components. The aim of the study was to determine whether TGF-β1 plays a role in the development of equine endometrosis. In Exp. 1, endometrial expression of α-SMA in different stages of endometrosis was determined. In endometrial tissues from the mid luteal phase (n=6 for each stages of endometrosis) and the follicular phase of the estrous cycle (n=5 for each stages of endometrosis), mRNA transcription and protein expression of α-Sma were evaluated by Realtime PCR and Western-blot, respectively. The α-Sma mRNA transcription and protein expression levels were correlated with the severity of endometrosis (P<0.05). In both phases of the estrous cycle, α-SMA protein expression was up-regulated in final stage of endometrosis compared to initial stage (P<0.05). In Exp. 2, the dose-and time-dependent effects of TGF-β1 on expression of α-SMA and ECM components were determined, as well as cell proliferation of equine fibroblasts. Equine endometrial fibroblasts (n=6, Kenney and Doig category I) were stimulated with vehicle or TGF-β1 (1, 5, 10 ng/ml) for 24, 48 or 72 h. Then, mRNA transcription of α-Sma, collagen type I (Col1a1), collagen type III (Col3a1) and fibronectin 1 (Fn1) were determined by Real-time PCR. The production of ECM components was determined by ELISA. Transforming growth factor-β1 increased the mRNA transcription of α-Sma and ECM components in a dose-and time-dependent manner in cultured endometrial fibroblasts (P<0.05). Additionally, TGF-β1 at a dose of 10 ng/ml increased α-SMA protein expression and COL1, COL3, FN production after 72 h of stimulation (P<0.05). The data showed a positive linkage between the presence of myofibroblasts and severity of endometrosis. We conclude that TGF-β1 may participate in pathological fibrotic changes in equine endometrial tissue by induction of myofibroblast differentiation, increased production of ECM components and fibroblast proliferation.
Biology of Reproduction, 2008
Reproduction (Cambridge, England), Jan 28, 2015
The human endometrium is a fertility-determining tissue and a target of steroid hormones' act... more The human endometrium is a fertility-determining tissue and a target of steroid hormones' action. Endocrine disruptors (EDs) can exert adverse effects on the physiological function of the decidua at the maternal - fetal interface. We examined the potential effects of an ED, bisphenol A (BPA), on endometrial maturation/decidualization, receptivity and secretion of decidual factors (biomarkers). In vitro decidualized, endometrial stromal cells from six hysterectomy specimens were treated with 1 pM - 1 mM of BPA, for 24 h and assessed for cell viability and proliferation. Three non-toxic concentrations of BPA (1 μM, 1 nM, 1 pM) were selected to study its influence on secretion of cell decidualization biomarkers (insulin-like growth factor binding protein, IGFBP-1; decidual prolactin, dPRL), macrophage migration inhibitory factor (MIF) secretion and hormone receptors' expression (estrogen receptors: ERα, ERβ; progesterone receptors: PRA, PRB; human chorionic gonadotropin/luteini...
Polish Journal of Veterinary Sciences, 2013
Information on the prevalence of subclinical endometritis and its mechanism in repeat breeding co... more Information on the prevalence of subclinical endometritis and its mechanism in repeat breeding cows is very limited. The aims of this study were: a) to evaluate the incidence of this disorder with cytobrush cytology b) to analyze mRNA expression of tumor necrosis factor α (TNFα) and inducible nitric oxide synthase (iNOS) in endometrial biopsy samples collected from repeat breeding cows with and without subclinical endometritis. Two experiments were carried out. In experiment 1, 112 (12.4%) repeat breeding cows (inseminated at least 3 times and not pregnant) were selected out of 902 cows from 8 dairy herds. Cytobrush cytology was performed on these cows, using the threshold of 10% PMNs in uterine smears. The results showed that 45 out of the 112 cows (40.2%) were diagnosed as having subclinical endometritis. In experiment 2, uterine biopsy samples were taken from repeat breeding cows with subclinical endometritis (n = 10) and without this disorder (n = 10). Using reverse transcriptio...
REPRODUCTION, 2010
Recently, we showed that leukotrienes (LTs) regulate ovarian cell functionin vitro. The aim of th... more Recently, we showed that leukotrienes (LTs) regulate ovarian cell functionin vitro. The aim of this study was to examine the role of LTs in corpus luteum (CL) function during both the estrous cycle and early pregnancyin vivo. mRNA expression of LT receptors (BLTfor LTB4andCYSLTfor LTC4), and 5-lipoxygenase (5-LO) in CL tissue and their localization in the ovary were studied during the estrous cycle and early pregnancy. Moreover, concentrations of LTs (LTB4and C4) in the CL tissue and blood were measured.5-LOandBLTmRNA expression increased on days 16–18 of the cycle, whereasCYSLTmRNA expression increased on days 16–18 of the pregnancy. The level of LTB4was evaluated during pregnancy compared with the level of LTC4, which increased during CL regression. LT antagonists influenced the duration of the estrous cycle: the LTC4antagonist (azelastine) prolonged the luteal phase, whereas the LTB4antagonist (dapsone) caused earlier luteolysisin vivo. Dapsone decreased progesterone (P4) secreti...
Reproduction in domestic animals = Zuchthygiene, 2012
Previous in vitro studies demonstrated that bovine endometrium has the capacity to convert inacti... more Previous in vitro studies demonstrated that bovine endometrium has the capacity to convert inactive cortisone to biologically active cortisol (Cr) and that Cr inhibits cytokine-stimulated prostaglandin F(2α) (PGF) production. This study was carried out to test the hypothesis that bovine reproductive tract has the capacity to convert cortisone to Cr in vivo and to evaluate the effects of intravaginal application of exogenous cortisone on uterine PGF secretion during the late luteal stage. The temporal relationships between PGF and Cr levels in uterine plasma were also determined. Catheters were inserted into jugular vein (JV), uterine vein (UV), vena cava caudalis (VCC) and aorta abdominalis (AA) of six cows on Day 15 of the oestrous cycle (ovulation = Day 0) for frequent blood collection. On Day 16, the cows were divided randomly into two groups and infused intravaginally with vaseline gel (10 ml; control; n = 3) or cortisone dissolved in vaseline gel (100 mg; n = 3). Blood samples ...
The Veterinary Journal, 2015
Reproduction (Cambridge, England), 2015
Prostaglandin endoperoxide synthase-2 (PTGS2), tumour necrosis factor-alpha-induced protein-6 (TN... more Prostaglandin endoperoxide synthase-2 (PTGS2), tumour necrosis factor-alpha-induced protein-6 (TNFAIP6), pentraxin-3 (PTX3), epidermal growth factor-like factors: amphiregulin (AREG) and epiregulin (EREG) are essential for successful ovulation. In this study, we compared the induction of these ovulatory genes in bovine granulosa cells (GCs) in vivo (after LH surge) and in vitro (forskolin (FRS) treatment). These genes were markedly stimulated in GCs isolated from cows 21 h after LH-surge. In isolated GCs, FRS induced a distinct temporal profile for each gene. Generally, there was a good agreement between the in vivo and in vitro inductions of these genes except for PTX3. Lack of PTX3 induction in isolated GCs culture suggests that other follicular compartments may mediate its induction by LH. Next, to study the role of PTGS2 and prostaglandins (PGs) in the cascade of ovulatory genes, PTGS2 was silenced with siRNA. PTGS2 siRNA caused a marked and specific knockdown of PTGS2 mRNA and ...
The Veterinary Journal, 2014
Although prostaglandin (PG) F 2a analogues are routinely used for oestrus synchronisation in catt... more Although prostaglandin (PG) F 2a analogues are routinely used for oestrus synchronisation in cattle, their effects on the function of the bovine corpus luteum (CL), and on ovarian arterial contractility, may not reflect the physiological effects of endogenous PGF 2a . In the first of two related experiments, the effects of different analogues of PGF 2a (aPGF 2a ) on the secretory function and apoptosis of cultured bovine cells of the CL were assessed. Enzymatically-isolated bovine luteal cells (from between days 8 and 12 of the oestrous cycle), were stimulated for 24 h with naturally-occurring PGF 2a or aPGF 2a (dinoprost, cloprostenol or luprostiol). Secretion of progesterone (P4) was determined and cellular [Ca 2+ ] i mobilisation, as well as cell viability and apoptosis were measured.
Reproductive Biology, 2013
Theriogenology, 2012
Cell cultures are useful for determining the responses of specific cell types to various factors ... more Cell cultures are useful for determining the responses of specific cell types to various factors under controlled conditions and for obtaining a better understanding of in vivo physiologic processes. The aims of the present study were (i) to establish methodologies for isolation, culture and cryopreservation of equine endometrial epithelial and stromal cells; and (ii) to determine the effect of passage and cryopreservation on endometrial cell physiology, based on their basal and oxytocin (OT)-stimulated prostaglandin (PG) release. Epithelial and stromal cells were obtained by enzymatic digestion of equine endometrium collected from Days 2-5 of the estrous cycle (n ϭ 16). Primary epithelial and stromal cells, as well as cryopreserved cells were stimulated with OT (10 Ϫ7 M) for 24 h. The concentrations of PGE 2 and PGF 2␣ in the culture medium were measured by enzyme-linked immunosorbent assay (EIA). Oxytocin increased PGE 2 and PGF 2␣ release by primary cultures of unfrozen epithelial cells until passage I (P Ͻ 0.01) and by the primary culture of unfrozen and cryopreserved/thawed stromal cells until passage IV (P Ͻ 0.01). Cryopreserved/thawed stromal cells cultured up to passage IV and unfrozen epithelial cells derived from passage I have physiological properties similar to those observed in primary culture and may be successfully used for in vitro studies of PG secretion.
Theriogenology, 2012
Accurate regulation of the reproductive cycle and successful implantation depend on proper functi... more Accurate regulation of the reproductive cycle and successful implantation depend on proper functioning of the endometrium. The aim of this study was to determine whether mRNA transcription of specific enzymes responsible for prostaglandin (PG) synthesis (prostaglandinendoperoxide synthase, PTGS-2; prostaglandin F 2␣ synthase, PGFS; and prostaglandin E 2 synthases, PGES) and PG concentrations in endometrial extracts would change in moderate (Kenney's Category II) and severe phases of fibrosis (Kenney's Category III; endometrosis), compared with healthy endometrium (Kenney's Category I), during the estrous cycle. Endometrial tissues samples were obtained from mares at the early (n ϭ 12), mid (n ϭ 12) and late (n ϭ 12) luteal phases and the follicular phase (n ϭ 12) of the estrous cycle. Additionally, all endometria were classified microscopically as belonging to Categories I and II or III according to the Kenney classification, resulting in allocation of 4 samples for each subcategory, e.g., mid luteal I, II and III. Relative mRNA transcription was quantified using Real-time PCR. Concentrations of PGE 2 and PGF 2␣ in the endometrial extracts were determined using enzyme-linked immunosorbent assay (EIA). In Category I, PTGS-2 mRNA transcription was upregulated at the mid (P Ͻ 0.05) and late luteal phases (P Ͻ 0.001) and at the follicular phase (P Ͻ 0.05) compared to the early luteal phase. PGFS mRNA transcription as well as PGF 2␣ concentrations increased at the mid (P Ͻ 0.01) and late (P Ͻ 0.05) luteal phases compared to the early luteal phase in Category I. PGES mRNA transcription was higher at the mid (P Ͻ 0.01) and late luteal phases (P Ͻ 0.05) compared to the early luteal and follicular phases in Category I. Prostaglandin E 2 concentration in Category I was higher at the mid luteal phase (P Ͻ 0.01) compared to all other phases of the estrous cycle. During incipient endometrosis (Category II) and under full endometrosis (Category III), PTGS-2, PGFS and PGES mRNA transcription and PG concentration were altered compared to the respective estrous phases in healthy endometria (P Ͻ 0.05). It may be concluded that serious changes in mRNA transcription of PG synthases and PG production that occur in the equine endometrium during the course of fibrosis in the estrous cycle could be responsible for disturbances leading to disorders of the estrous cycle and early embryo losses.
Animal - science proceedings
Animal - science proceedings
Journal of Equine Veterinary Science, 2018
Animal - science proceedings
ABSTRACT Background / Purpose: The interactions between luteal, vascular endothelial, immune cell... more ABSTRACT Background / Purpose: The interactions between luteal, vascular endothelial, immune cells and its products: steroids, peptide hormones, prostaglandins (PGs), growth factors and cytokines play a pivotal role in the regulation of corpus luteum (CL) function. Luteal endothelial cells undergo many dynamic morphological changes and their action is regulated by cytokines.To establish an in vitro model for bovine luteal endothelial cells examination. To study the effect of cytokines: tumor necrosis factor α (TNF) and interferon γ (IFN) on cell viability, leukotrienes (LTs) and PG synthases, and endothelin-1 (EDN-1) mRNA, protein expression and their secretion in bovine immortalized luteal endothelial (EnCL-1) cells. Main conclusion: EDN-1, PGs and LTs are produced and secreted by immortalized BEC showing proper secretory function of immortalized BEC. Immortalized BEC are sensitive on TNF action and this cytokine modulates expressions for enzymes responsible for production of AA metabolites and its levels.
Theriogenology, 2019
Transforming growth factor (TGF)-β1 not only regulates cell growth, development, and tissue remod... more Transforming growth factor (TGF)-β1 not only regulates cell growth, development, and tissue remodeling, but it also participates in the pathogenesis of tissue fibrosis. In the equine endometrium, the concentration of TGF-β1 is correlated with endometrosis (equine endometrial fibrosis). In other tissues, TGF-β1 induces differentiation of many cell types into myofibroblasts. These cells are characterized by α-smooth muscle actin (α-SMA) expression and an ability to deposit excessive amounts of extracellular matrix (ECM) components. The aim of the study was to determine whether TGF-β1 plays a role in the development of equine endometrosis. In Exp. 1, endometrial expression of α-SMA in different stages of endometrosis was determined. In endometrial tissues from the mid luteal phase (n=6 for each stages of endometrosis) and the follicular phase of the estrous cycle (n=5 for each stages of endometrosis), mRNA transcription and protein expression of α-Sma were evaluated by Realtime PCR and Western-blot, respectively. The α-Sma mRNA transcription and protein expression levels were correlated with the severity of endometrosis (P<0.05). In both phases of the estrous cycle, α-SMA protein expression was up-regulated in final stage of endometrosis compared to initial stage (P<0.05). In Exp. 2, the dose-and time-dependent effects of TGF-β1 on expression of α-SMA and ECM components were determined, as well as cell proliferation of equine fibroblasts. Equine endometrial fibroblasts (n=6, Kenney and Doig category I) were stimulated with vehicle or TGF-β1 (1, 5, 10 ng/ml) for 24, 48 or 72 h. Then, mRNA transcription of α-Sma, collagen type I (Col1a1), collagen type III (Col3a1) and fibronectin 1 (Fn1) were determined by Real-time PCR. The production of ECM components was determined by ELISA. Transforming growth factor-β1 increased the mRNA transcription of α-Sma and ECM components in a dose-and time-dependent manner in cultured endometrial fibroblasts (P<0.05). Additionally, TGF-β1 at a dose of 10 ng/ml increased α-SMA protein expression and COL1, COL3, FN production after 72 h of stimulation (P<0.05). The data showed a positive linkage between the presence of myofibroblasts and severity of endometrosis. We conclude that TGF-β1 may participate in pathological fibrotic changes in equine endometrial tissue by induction of myofibroblast differentiation, increased production of ECM components and fibroblast proliferation.
Biology of Reproduction, 2008
Reproduction (Cambridge, England), Jan 28, 2015
The human endometrium is a fertility-determining tissue and a target of steroid hormones' act... more The human endometrium is a fertility-determining tissue and a target of steroid hormones' action. Endocrine disruptors (EDs) can exert adverse effects on the physiological function of the decidua at the maternal - fetal interface. We examined the potential effects of an ED, bisphenol A (BPA), on endometrial maturation/decidualization, receptivity and secretion of decidual factors (biomarkers). In vitro decidualized, endometrial stromal cells from six hysterectomy specimens were treated with 1 pM - 1 mM of BPA, for 24 h and assessed for cell viability and proliferation. Three non-toxic concentrations of BPA (1 μM, 1 nM, 1 pM) were selected to study its influence on secretion of cell decidualization biomarkers (insulin-like growth factor binding protein, IGFBP-1; decidual prolactin, dPRL), macrophage migration inhibitory factor (MIF) secretion and hormone receptors' expression (estrogen receptors: ERα, ERβ; progesterone receptors: PRA, PRB; human chorionic gonadotropin/luteini...
Polish Journal of Veterinary Sciences, 2013
Information on the prevalence of subclinical endometritis and its mechanism in repeat breeding co... more Information on the prevalence of subclinical endometritis and its mechanism in repeat breeding cows is very limited. The aims of this study were: a) to evaluate the incidence of this disorder with cytobrush cytology b) to analyze mRNA expression of tumor necrosis factor α (TNFα) and inducible nitric oxide synthase (iNOS) in endometrial biopsy samples collected from repeat breeding cows with and without subclinical endometritis. Two experiments were carried out. In experiment 1, 112 (12.4%) repeat breeding cows (inseminated at least 3 times and not pregnant) were selected out of 902 cows from 8 dairy herds. Cytobrush cytology was performed on these cows, using the threshold of 10% PMNs in uterine smears. The results showed that 45 out of the 112 cows (40.2%) were diagnosed as having subclinical endometritis. In experiment 2, uterine biopsy samples were taken from repeat breeding cows with subclinical endometritis (n = 10) and without this disorder (n = 10). Using reverse transcriptio...
REPRODUCTION, 2010
Recently, we showed that leukotrienes (LTs) regulate ovarian cell functionin vitro. The aim of th... more Recently, we showed that leukotrienes (LTs) regulate ovarian cell functionin vitro. The aim of this study was to examine the role of LTs in corpus luteum (CL) function during both the estrous cycle and early pregnancyin vivo. mRNA expression of LT receptors (BLTfor LTB4andCYSLTfor LTC4), and 5-lipoxygenase (5-LO) in CL tissue and their localization in the ovary were studied during the estrous cycle and early pregnancy. Moreover, concentrations of LTs (LTB4and C4) in the CL tissue and blood were measured.5-LOandBLTmRNA expression increased on days 16–18 of the cycle, whereasCYSLTmRNA expression increased on days 16–18 of the pregnancy. The level of LTB4was evaluated during pregnancy compared with the level of LTC4, which increased during CL regression. LT antagonists influenced the duration of the estrous cycle: the LTC4antagonist (azelastine) prolonged the luteal phase, whereas the LTB4antagonist (dapsone) caused earlier luteolysisin vivo. Dapsone decreased progesterone (P4) secreti...
Reproduction in domestic animals = Zuchthygiene, 2012
Previous in vitro studies demonstrated that bovine endometrium has the capacity to convert inacti... more Previous in vitro studies demonstrated that bovine endometrium has the capacity to convert inactive cortisone to biologically active cortisol (Cr) and that Cr inhibits cytokine-stimulated prostaglandin F(2α) (PGF) production. This study was carried out to test the hypothesis that bovine reproductive tract has the capacity to convert cortisone to Cr in vivo and to evaluate the effects of intravaginal application of exogenous cortisone on uterine PGF secretion during the late luteal stage. The temporal relationships between PGF and Cr levels in uterine plasma were also determined. Catheters were inserted into jugular vein (JV), uterine vein (UV), vena cava caudalis (VCC) and aorta abdominalis (AA) of six cows on Day 15 of the oestrous cycle (ovulation = Day 0) for frequent blood collection. On Day 16, the cows were divided randomly into two groups and infused intravaginally with vaseline gel (10 ml; control; n = 3) or cortisone dissolved in vaseline gel (100 mg; n = 3). Blood samples ...
The Veterinary Journal, 2015
Reproduction (Cambridge, England), 2015
Prostaglandin endoperoxide synthase-2 (PTGS2), tumour necrosis factor-alpha-induced protein-6 (TN... more Prostaglandin endoperoxide synthase-2 (PTGS2), tumour necrosis factor-alpha-induced protein-6 (TNFAIP6), pentraxin-3 (PTX3), epidermal growth factor-like factors: amphiregulin (AREG) and epiregulin (EREG) are essential for successful ovulation. In this study, we compared the induction of these ovulatory genes in bovine granulosa cells (GCs) in vivo (after LH surge) and in vitro (forskolin (FRS) treatment). These genes were markedly stimulated in GCs isolated from cows 21 h after LH-surge. In isolated GCs, FRS induced a distinct temporal profile for each gene. Generally, there was a good agreement between the in vivo and in vitro inductions of these genes except for PTX3. Lack of PTX3 induction in isolated GCs culture suggests that other follicular compartments may mediate its induction by LH. Next, to study the role of PTGS2 and prostaglandins (PGs) in the cascade of ovulatory genes, PTGS2 was silenced with siRNA. PTGS2 siRNA caused a marked and specific knockdown of PTGS2 mRNA and ...
The Veterinary Journal, 2014
Although prostaglandin (PG) F 2a analogues are routinely used for oestrus synchronisation in catt... more Although prostaglandin (PG) F 2a analogues are routinely used for oestrus synchronisation in cattle, their effects on the function of the bovine corpus luteum (CL), and on ovarian arterial contractility, may not reflect the physiological effects of endogenous PGF 2a . In the first of two related experiments, the effects of different analogues of PGF 2a (aPGF 2a ) on the secretory function and apoptosis of cultured bovine cells of the CL were assessed. Enzymatically-isolated bovine luteal cells (from between days 8 and 12 of the oestrous cycle), were stimulated for 24 h with naturally-occurring PGF 2a or aPGF 2a (dinoprost, cloprostenol or luprostiol). Secretion of progesterone (P4) was determined and cellular [Ca 2+ ] i mobilisation, as well as cell viability and apoptosis were measured.
Reproductive Biology, 2013
Theriogenology, 2012
Cell cultures are useful for determining the responses of specific cell types to various factors ... more Cell cultures are useful for determining the responses of specific cell types to various factors under controlled conditions and for obtaining a better understanding of in vivo physiologic processes. The aims of the present study were (i) to establish methodologies for isolation, culture and cryopreservation of equine endometrial epithelial and stromal cells; and (ii) to determine the effect of passage and cryopreservation on endometrial cell physiology, based on their basal and oxytocin (OT)-stimulated prostaglandin (PG) release. Epithelial and stromal cells were obtained by enzymatic digestion of equine endometrium collected from Days 2-5 of the estrous cycle (n ϭ 16). Primary epithelial and stromal cells, as well as cryopreserved cells were stimulated with OT (10 Ϫ7 M) for 24 h. The concentrations of PGE 2 and PGF 2␣ in the culture medium were measured by enzyme-linked immunosorbent assay (EIA). Oxytocin increased PGE 2 and PGF 2␣ release by primary cultures of unfrozen epithelial cells until passage I (P Ͻ 0.01) and by the primary culture of unfrozen and cryopreserved/thawed stromal cells until passage IV (P Ͻ 0.01). Cryopreserved/thawed stromal cells cultured up to passage IV and unfrozen epithelial cells derived from passage I have physiological properties similar to those observed in primary culture and may be successfully used for in vitro studies of PG secretion.
Theriogenology, 2012
Accurate regulation of the reproductive cycle and successful implantation depend on proper functi... more Accurate regulation of the reproductive cycle and successful implantation depend on proper functioning of the endometrium. The aim of this study was to determine whether mRNA transcription of specific enzymes responsible for prostaglandin (PG) synthesis (prostaglandinendoperoxide synthase, PTGS-2; prostaglandin F 2␣ synthase, PGFS; and prostaglandin E 2 synthases, PGES) and PG concentrations in endometrial extracts would change in moderate (Kenney's Category II) and severe phases of fibrosis (Kenney's Category III; endometrosis), compared with healthy endometrium (Kenney's Category I), during the estrous cycle. Endometrial tissues samples were obtained from mares at the early (n ϭ 12), mid (n ϭ 12) and late (n ϭ 12) luteal phases and the follicular phase (n ϭ 12) of the estrous cycle. Additionally, all endometria were classified microscopically as belonging to Categories I and II or III according to the Kenney classification, resulting in allocation of 4 samples for each subcategory, e.g., mid luteal I, II and III. Relative mRNA transcription was quantified using Real-time PCR. Concentrations of PGE 2 and PGF 2␣ in the endometrial extracts were determined using enzyme-linked immunosorbent assay (EIA). In Category I, PTGS-2 mRNA transcription was upregulated at the mid (P Ͻ 0.05) and late luteal phases (P Ͻ 0.001) and at the follicular phase (P Ͻ 0.05) compared to the early luteal phase. PGFS mRNA transcription as well as PGF 2␣ concentrations increased at the mid (P Ͻ 0.01) and late (P Ͻ 0.05) luteal phases compared to the early luteal phase in Category I. PGES mRNA transcription was higher at the mid (P Ͻ 0.01) and late luteal phases (P Ͻ 0.05) compared to the early luteal and follicular phases in Category I. Prostaglandin E 2 concentration in Category I was higher at the mid luteal phase (P Ͻ 0.01) compared to all other phases of the estrous cycle. During incipient endometrosis (Category II) and under full endometrosis (Category III), PTGS-2, PGFS and PGES mRNA transcription and PG concentration were altered compared to the respective estrous phases in healthy endometria (P Ͻ 0.05). It may be concluded that serious changes in mRNA transcription of PG synthases and PG production that occur in the equine endometrium during the course of fibrosis in the estrous cycle could be responsible for disturbances leading to disorders of the estrous cycle and early embryo losses.