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Mariusz P Kowalewski - One of the best experts on this subject based on the ideXlab platform.

  • Gene expression profiling of the canine placenta during normal and Antigestagen-induced luteolysis
    General and Comparative Endocrinology, 2019
    Co-Authors: Marta Nowak, Serhan Serhat Ay, Ewa Kautz, Hubert Rehrauer, Alois Boos, Murat Findik, Mariusz P Kowalewski
    Abstract:

    Abstract The domestic dog is the only domestic animal species that does not produce steroids in the placenta and instead relies on luteal steroids throughout pregnancy. Nevertheless, the canine placenta is highly responsive to steroids, and withdrawal of progesterone (P4) affects the feto-maternal unit, initializing the parturition cascade. Similar effects can be observed during Antigestagen-induced abortion. Here, aiming to provide new insights into mechanisms involved in the termination of canine pregnancy, next generation sequencing (NGS, RNA-seq) was applied. Placental transcriptomes derived from natural prepartum and Antigestagen-induced abortions were analyzed and compared with fully developed mid-gestation placentas. The contrast “prepartum luteolysis over mid-gestation” revealed 1973 differentially expressed genes (DEG). Terms associated with apoptosis, impairment of vascular function and activation of signaling of several cytokines (e.g., IL-8, IL-3, TGF-β) were overrepresented at natural luteolysis. When compared with mid-term, Antigestagen treatment revealed 135 highly regulated DEG that were involved in the induced luteolysis and showed similar associations with functional terms and expression patterns as during natural luteolysis. The contrast “Antigestagen-induced luteolysis over prepartum luteolysis” revealed that, although similar changes occur in both conditions, they are more pronounced during natural prepartum. Among P4-regulated DEG were those related to immune system and cortisol metabolism. It appears that, besides inducing placental PGF2α output, both natural and induced P4 withdrawal is associated with disruption of the feto-maternal interface, leading to impaired vascular functions, apoptosis and controlled modulation of the immune response. The time-related maturation of the feto-maternal interface needs to be considered because it may be clinically relevant.

  • Luteal ANGPT-TIE system during selected stages of pregnancy, and normal and Antigestagen-induced luteolysis in the dog.
    Reproduction (Cambridge England), 2018
    Co-Authors: Aykut Gram, Alois Boos, Miguel Tavares Pereira, Anna T. Grazul-bilska, Mariusz P Kowalewski
    Abstract:

    Abstract Rapid establishment of a vascular network is essential for normal functionality of the corpus luteum (CL). The early luteal phase is associated with increased expression of the VEGF system in canine CL. Acting in synchrony with angiopoietins (ANGPTs), VEGF system plays major roles in stabilization of blood vessels. However, the expression of the ANGPT system has not yet been investigated in the dog. Therefore, here, we investigated the luteal expression of ANGPT1, -2, and of their receptors TIE1 and -2, in pregnant dogs at selected time points during pregnancy and at normal and Antigestagen-induced luteolysis. Additionally, luteal cells from early CL were incubated with PGE2 and its effects on the ANGPT system were assessed. Whereas the luteal ANGPT1 was stable until mid-gestation, TIE1 was elevated post-implantation, their expression decreased toward prepartum luteolysis. The ANGPT2- and TIE2-mRNA did not vary during pregnancy. The ANGPT2/ANGPT1 ratio was elevated during prepartum luteolysis. PGE2 increased ANGPT2, but suppressed ANGPT1 levels. None of the ANGPT-system members was affected by Antigestagen treatment in mid-pregnancy. Localization of ANGPT1 was predominantly found in the tunica intima and media of vessels and ANGPT2 stained strongly in luteal cells. Both ANGPTs were localized in macrophages. TIE1 stained in the vascular tunica media, in luteal cells and macrophages, whereas TIE2 was colocalized with ANGPT1 in vascular components. In conclusion, high expression of ANGPT1 during the increased presence of VEGFA in early canine CL implies its contribution to vascular network development. The upregulation of the ANGPT2/ANGPT1 ratio during prepartum luteolysis indicates involvement of the ANGPT system in PGF2α-mediated vascular destabilization.

  • expression and functional implications of luteal endothelins in pregnant and non pregnant dogs
    Reproduction, 2015
    Co-Authors: Aykut Gram, Alois Boos, Sophie Latter, B Hoffmann, Mariusz P Kowalewski
    Abstract:

    Luteal development is regulated by many locally produced mediators, e.g., prostaglandins and angiogenic factors. However, the role and function of vasoactive factors in the canine corpus luteum (CL) remain largely unknown. Consequently, expression of the endothelin (ET) receptors-A and -B (ETA and ETB, revealing vasoconstriction and vasodilator properties respectively), the ET-converting enzyme (ECE1) and ET1, -2 and -3 were investigated in CL from non-pregnant dogs (days 5, 15, 25, 35, 45 and 65 post-ovulation), and at selected stages of pregnancy (pre-implantation, post-implantation, mid-gestation), and during normal and Antigestagen-induced prepartum luteolysis/abortion. The interrelationship between PGE2 and the ET system was investigated in PGE2-treated canine primary lutein cells from early CL. ET1 did not change significantly over time; ET2, ECE1 and ETB were elevated in early CL and were downregulated towards the mid/late-luteal phase. The prepartum increase of ET2 was significant. ET3 increased gradually, and was highest in late CL and/or at prepartum luteolysis. ETA remained constant until the late CL phase and increased only during prepartum luteolysis. ET1 was localized to the luteal cells, and ET2, ET3 and ETA to vascular endothelium. ECE1 and ETB were detected at both locations. Except for upregulated ET1 and lack of effect on ET2, Antigestagen applied to mid-pregnant dogs evoked similar changes to those observed during normal luteolysis. PGE2 upregulated ETB in treated cells; ETA and ET1 remained unaffected, and ET2 decreased. A modulatory role of the ETs in canine CL, possibly in association with other factors (e.g., PGE2 and progesterone receptor), is strongly indicated.

  • expression and localization of vascular endothelial growth factor a vegfa and its two receptors vegfr1 flt1 and vegfr2 flk1 kdr in the canine corpus luteum and utero placental compartments during pregnancy and at normal and induced parturition
    General and Comparative Endocrinology, 2015
    Co-Authors: Aykut Gram, Alois Boos, B Hoffmann, Mariusz P Kowalewski
    Abstract:

    VEGFA is one of the most potent known inducers of angiogenesis. However, the function of angiogenic factors in the canine corpus luteum (CL) of pregnancy and in the pregnant uterus and placenta has not yet been elucidated. Therefore, here we investigated the expression and localization of VEGFA and its receptors (VEGFR1/FLT1 and VEGFR2/FLK1/KDR) in the canine CL and utero-placental compartments (ut-pl) throughout pregnancy until prepartum luteolysis. Antigestagen-mediated effects on expression of VEGF system in ut-pl were elucidated in mid-pregnant dogs. While displaying high individual variation, the luteal VEGFA was elevated during pre-implantation and post-implantation, followed by a decrease during mid-gestation, which was more pronounced at the mRNA level, and showed constant expression afterwards. Within the uterus, it increased following implantation and during mid-gestation in ut-pl compartments, but was downregulated at prepartum luteolysis. Luteal VEGFR1 expression resembled that of VEGFA; VEGFR2 remained unaffected throughout pregnancy. In ut-pl compartments, both receptors increased gradually towards mid-gestation; a prepartum decrease was observed for VEGFR1. Antigestagen-treatment resulted in decreased expression of ut-pl VEGFR1. In the CL, VEGFA stained in luteal cells. Uterine signals of VEGFA and its two receptors were observed in epithelial and vascular compartments, and in myometrium. In placental labyrinth, additionally, trophoblast stained positively. Luteal VEGFR1 was localized to the luteal cells and tunica media of blood vessels, whereas VEGFR2 stained only in capillary endothelial cells. The upregulation of luteal and the ut-pl VEGF system during early gestational stages supports the increased vascularization rate during this time. The diminishing effects of the prepartum endocrine milieu on VEGFA function seem to be more pronounced in the ut-pl units.

  • Luteal and placental function in the bitch: spatio-temporal changes in prolactin receptor (PRLr) expression at dioestrus, pregnancy and normal and induced parturition
    Reproductive Biology and Endocrinology, 2011
    Co-Authors: Mariusz P Kowalewski, Alois Boos, Aykut Gram, Erika Michel, Franco Guscetti, Bernd Hoffmann, Selim Aslan, Iris Reichler
    Abstract:

    Background Endocrine mechanisms governing canine reproductive function remain still obscure. Progesterone (P4) of luteal origin is required for maintenance of pregnancy. Corpora lutea (CL) are gonadotrop-independent during the first third of dioestrus; afterwards prolactin (PRL) is the primary luteotropic factor. Interestingly, the increasing PRL levels are accompanied by decreasing P4 concentrations, thus luteal regression/luteolysis occurs in spite of an increased availability of gonadotropic support. PRL acts through its receptor (PRLr), the expression of which has not yet been thoroughly investigated at the molecular and cellular level in the dog. Methods The expression of PRLr was assessed in CL of non-pregnant dogs during the course of dioestrus (days 5, 15, 25, 35, 45, 65 post ovulation; p.o.) as well as in CL, the utero/placental compartments (Ut/Pl) and interplacental free polar zones (interplacental sites) from pregnant dogs during the pre-implantation, post-implantation and mid-gestation period of pregnancy and during the normal and Antigestagen-induced luteolysis. Expression of PRLr was tested by Real Time PCR, immunohistochemistry and in situ hybridization. Results In non-pregnant CL the PRLr expression was significantly upregulated at day 15 p.o. and decreased significantly afterwards, towards the end of dioestrus. CL of pregnancy showed elevated PRLr expression until mid gestation while prepartal downregulation was observed. Interestingly, placental but not interplacental expression of PRLr was strongly time-related; a significant upregulation was observed towards mid-gestation. Within the CL PRLr was localized to the luteal cells; in the Ut/Pl it was localized to the fetal trophoblast and epithelial cells of glandular chambers. Moreover, in mid-pregnant animals treated with an Antigestagen, both the luteal and placental, but not the uterine PRLr were significantly downregulated. Conclusions The data presented suggest that the luteal provision of P4 in both pregnant and non-pregnant dogs may be regulated at the PRLr level. Furthermore, a role of PRL not only in maintaining the canine CL function but also in regulating the placental function is strongly suggested. A possible functional interrelationship between luteal P4 and placental and luteal PRLr expression also with respect to the prepartal luteolysis is implied.

Meyer Andrea - One of the best experts on this subject based on the ideXlab platform.

  • Expression und mögliche Funktionen des Peroxisom-Proliferator aktivierter Rezeptor γ (PPARγ) im kaninen Corpus luteum und in der Plazenta während der Trächtigkeit und der normalen sowie induzierten Geburt
    2011
    Co-Authors: Meyer Andrea
    Abstract:

    Vetsuisse-Fakultät Universität Zürich 2011 Andrea Meyer Veterinäranatomisches Institut, sekretariat@vetanat.uzh.ch Expression und mögliche Funktionen des Peroxisome-Proliferator aktivierter Rezeptor γ (PPARγ) im kaninen Corpus luteum und in der Plazenta während der Trächtigkeit und der normalen sowie induzierten Geburt PPARγ, ein nukleärer Hormonrezeptor, spielt eine wichtige regulatorische Rolle bei der Reproduktion; er moduliert die steroidogene Kapazität der reproduktiven Organe und beeinflusst die Trophoblastendifferenzierung. Untersucht wurden mittels Ovariohysterektomie (OHE) entnommene Corpora lutea (CL) und uteroplazentäre Einheiten von Hündinnen an den Tagen 8-12 (Präimplantation; n=5), 18-25 (Postimplantation; n=5), 35-40 (mittlere Trächtigkeit; n=5) und während der präpartalen Luteolyse (n=3). Zusätzlich wurde während der mittleren Trächtigkeit (n=10) mit dem Antigestagen Aglepriston ein Abort ausgelöst (10mg/kg 2x/24Std.). Die OHE wurde 24 und 72Std. nach der zweiten Injektion durchgeführt. PPARγ wurde immunhistochemisch in Luteinzellen und Trophoblastzellen nachgewiesen. Western Blot und Real Time PCR zeigten im CL und uteroplazentären Gewebe eine Aufregulation während der Implantation und mittleren Trächtigkeit, gefolgt von einer Verminderung während der Luteolyse. Alle Veränderungen zeigten sich am deutlichsten auf Proteinebene. Die Behandlung mit Aglepriston führte zur lutealen und plazentären PPARγ- Downregulation. Die Daten sprechen für eine wichtige Rolle von PPARγ in der kaninen Reproduktion, vermutlich über die Regulation von Implantation und Trophoblastinvasion. Schlüsselwörter: PPARγ, Hündin, Corpus luteum, uteroplazentäre Einheit Vetsuisse-Faculty University of Zurich, 2011 Andrea Meyer Institute of Veterinary Anatomy, sekretariat@vetanat.uzh.ch Expression and functional implications of Peroxisome Proliferator-Activated Receptor γ (PPARγ) in canine reproductive tissues during normal pregnancy, parturition and induced abortion PPARγ is a nuclear hormone receptor that plays multiple roles in regulating function of reproductive tissues; it modifies their steroidogenic capacity and modulates the trophoblast differentiation. Corpora lutea (CL) and uteroplacental units of bitches were analyzed on days 8-12 (pre- implantation; n=5), 18-25 (post-implantation; n=5), 35-40 (mid-gestation; n=5) and during prepartal luteolysis (n=3); tissues were collected via ovariohysterectomy (OHE). In addition, mid-pregnant animals (n=10) were treated with the Antigestagen Aglepristone (10mg/kg, 2x/24h) to induce abortion; OHE was performed 24 and 72hours after the second injection. Within the CL immunhistochemistry localized PPARγ to the lutein cells, placental localization was in the trophoblast. As revealed by western blot and real time PCR, PPARγ was upregulated during implantation and mid-gestation in both compartments, followed by a prepartal downregulation. All changes were stronger pronounced at the protein level. The interference of Aglepristone with luteal and placental progesteron receptor led to a downregulation of PPARγ. These data suggest that PPARγ may be a factor involved in canine reproduction, possibly through regulating the processes of implantation and trophoblast invasion. Keywords: PPARγ, bitch, corpus luteum, uteroplacental uni

  • Expression und mögliche Funktionen des Peroxisom-Proliferator aktivierter Rezeptor γ (PPARγ) im kaninen Corpus luteum und in der Plazenta während der Trächtigkeit und der normalen sowie induzierten Geburt
    2011
    Co-Authors: Meyer Andrea
    Abstract:

    PPARγ, ein nukleärer Hormonrezeptor, spielt eine wichtige regulatorische Rolle bei der Reproduktion; er moduliert die steroidogene Kapazität der reproduktiven Organe und beeinflusst die Trophoblastendifferenzierung. Untersucht wurden mittels Ovariohysterektomie (OHE) entnommene Corpora lutea (CL) und uteroplazentäre Einheiten von Hündinnen an den Tagen 8-12 (Präimplantation; n=5), 18-25 (Postimplantation; n=5), 35-40 (mittlere Trächtigkeit; n=5) und während der präpartalen Luteolyse (n=3). Zusätzlich wurde während der mittleren Trächtigkeit (n=10) mit dem Antigestagen Aglepriston ein Abort ausgelöst (10mg/kg 2x/24Std.). Die OHE wurde 24 und 72Std. nach der zweiten Injektion durchgeführt. PPARγ wurde immunhistochemisch in Luteinzellen und Trophoblastzellen nachgewiesen. Western Blot und Real Time PCR zeigten im CL und uteroplazentären Gewebe eine Aufregulation während der Implantation und mittleren Trächtigkeit, gefolgt von einer Verminderung während der Luteolyse. Alle Veränderungen zeigten sich am deutlichsten auf Proteinebene. Die Behandlung mit Aglepriston führte zur lutealen und plazentären PPARγ- Downregulation. Die Daten sprechen für eine wichtige Rolle von PPARγ in der kaninen Reproduktion, vermutlich über die Regulation von Implantation und Trophoblastinvasion. PPARγ is a nuclear hormone receptor that plays multiple roles in regulating function of reproductive tissues; it modifies their steroidogenic capacity and modulates the trophoblast differentiation. Corpora lutea (CL) and uteroplacental units of bitches were analyzed on days 8-12 (pre-implantation; n=5), 18-25 (post-implantation; n=5), 35-40 (mid-gestation; n=5) and during prepartal luteolysis (n=3); tissues were collected via ovariohysterectomy (OHE). In addition, mid-pregnant animals (n=10) were treated with the Antigestagen Aglepristone (10mg/kg, 2x/24h) to induce abortion; OHE was performed 24 and 72hours after the second injection. Within the CL immunhistochemistry localized PPARγ to the lutein cells, placental localization was in the trophoblast. As revealed by western blot and real time PCR, PPARγ was upregulated during implantation and mid-gestation in both compartments, followed by a prepartal downregulation. All changes were stronger pronounced at the protein level. The interference of Aglepristone with luteal and placental progesteron receptor led to a downregulation of PPARγ. These data suggest that PPARγ may be a factor involved in canine reproduction, possibly through regulating the processes of implantation and trophoblast invasion

Aykut Gram - One of the best experts on this subject based on the ideXlab platform.

  • Luteal ANGPT-TIE system during selected stages of pregnancy, and normal and Antigestagen-induced luteolysis in the dog.
    Reproduction (Cambridge England), 2018
    Co-Authors: Aykut Gram, Alois Boos, Miguel Tavares Pereira, Anna T. Grazul-bilska, Mariusz P Kowalewski
    Abstract:

    Abstract Rapid establishment of a vascular network is essential for normal functionality of the corpus luteum (CL). The early luteal phase is associated with increased expression of the VEGF system in canine CL. Acting in synchrony with angiopoietins (ANGPTs), VEGF system plays major roles in stabilization of blood vessels. However, the expression of the ANGPT system has not yet been investigated in the dog. Therefore, here, we investigated the luteal expression of ANGPT1, -2, and of their receptors TIE1 and -2, in pregnant dogs at selected time points during pregnancy and at normal and Antigestagen-induced luteolysis. Additionally, luteal cells from early CL were incubated with PGE2 and its effects on the ANGPT system were assessed. Whereas the luteal ANGPT1 was stable until mid-gestation, TIE1 was elevated post-implantation, their expression decreased toward prepartum luteolysis. The ANGPT2- and TIE2-mRNA did not vary during pregnancy. The ANGPT2/ANGPT1 ratio was elevated during prepartum luteolysis. PGE2 increased ANGPT2, but suppressed ANGPT1 levels. None of the ANGPT-system members was affected by Antigestagen treatment in mid-pregnancy. Localization of ANGPT1 was predominantly found in the tunica intima and media of vessels and ANGPT2 stained strongly in luteal cells. Both ANGPTs were localized in macrophages. TIE1 stained in the vascular tunica media, in luteal cells and macrophages, whereas TIE2 was colocalized with ANGPT1 in vascular components. In conclusion, high expression of ANGPT1 during the increased presence of VEGFA in early canine CL implies its contribution to vascular network development. The upregulation of the ANGPT2/ANGPT1 ratio during prepartum luteolysis indicates involvement of the ANGPT system in PGF2α-mediated vascular destabilization.

  • Transcriptome analysis reveals differences in mechanisms regulating cessation of luteal function in pregnant and non-pregnant dogs
    BMC Genomics, 2017
    Co-Authors: Sophie Zatta, Hubert Rehrauer, Alois Boos, Aykut Gram, Mariusz Pawel Kowalewski
    Abstract:

    Background In the domestic dog, corpora lutea (CL) are the only source of progesterone (P4), both in pregnant and non-pregnant cycles because there is no placental steroidogenesis. The absence of an endogenous luteolysin in absence of pregnancy results in long-lasting physiological pseudopregnancy, strongly contrasting with the acute luteolysis observed prepartum. The underlying biological mechanisms and the involvement of P4 signalling remain, however, not fully understood. Therefore, here, next-generation sequencing (RNA-Seq) was performed on CL from the late luteal phase and compared with normally luteolyzing CL collected at the prepartum P4 decrease. Results The contrast “luteal regression over luteolysis” yielded 1595 differentially expressed genes (DEG). The CL in late luteal regression were predominantly associated with functional terms linked to extracellular matrix ( p  = 5.52e-05). Other terms related to transcriptional activity ( p  = 2.45e-04), and steroid hormone signalling ( p  = 2.29e-04), which were more highly represented in late regression than during luteolysis. The prepartum luteolysis was associated with immune inflammatory responses ( p  = 2.87e-14), including acute-phase reaction ( p  = 4.10e-06). Immune system-related events were also more highly represented in CL derived from normal luteolysis ( p  = 7.02e-04), compared with those from dogs in which luteolysis was induced with an Antigestagen (1480 DEG in total). Additionally, the withdrawal of P4 at mid-gestation resulted in 92 DEG; over-represented terms enriched in Antigestagen-treated dogs were related to the inflammatory response ( p  = 0.005) or response to IL1 ( p  = 7.29e-05). Terms related to proliferation, e.g., centrosome organization ( p  = 0.002) and steroid metabolic processes ( p  = 0.001), prevailed at mid-gestation. Thereby, our results revealed the nature of luteotropic effects of P4 within canine CL. It appears that, even though they result in diminished steroidogenic output, the effect of Antigestagens is more related to the withdrawal of P4 support than to the PGF2alpha-related inflammatory reaction observed at physiological parturition. Conclusions We report the differential gene expression associated with maintenance and cessation of luteal function in pregnant and non-pregnant dogs. Based on the differentially expressed genes, we indicate functional pathways and gene networks that are potentially involved in the underlying endocrine and molecular mechanisms. This study establishes future research directions that may be helpful in understanding some of the clinical conditions, such as luteal insufficiency, associated with negative pregnancy outcome in dogs.

  • Additional file 6: of Transcriptome analysis reveals differences in mechanisms regulating cessation of luteal function in pregnant and non-pregnant dogs
    2017
    Co-Authors: Sophie Zatta, Hubert Rehrauer, Alois Boos, Aykut Gram, Mariusz Kowalewski
    Abstract:

    Venn-diagrams, combined results for Figs. 3 and 4. An overview of overlapping genes commonly expressed between the selected contrasts: (contrast 1) “luteal regression over luteolysis” and (contrast 2) “mid-gestation over Antigestagen”, or (contrast 1) “luteolysis over Antigestagen” and (contrast 2) “mid-gestation over luteolysis”. There are separate lists for each set threshold: genes expressed solely in either of the contrasts, and genes commonly expressed in both contrasts. (XLSX 67 kb

  • Additional file 4: of Transcriptome analysis reveals differences in mechanisms regulating cessation of luteal function in pregnant and non-pregnant dogs
    2017
    Co-Authors: Sophie Zatta, Hubert Rehrauer, Alois Boos, Aykut Gram, Mariusz Kowalewski
    Abstract:

    List of DEG found in the contrast “luteolysis over Antigestagen”. All genes detected with p 

  • Additional file 3: of Transcriptome analysis reveals differences in mechanisms regulating cessation of luteal function in pregnant and non-pregnant dogs
    2017
    Co-Authors: Sophie Zatta, Hubert Rehrauer, Alois Boos, Aykut Gram, Mariusz Kowalewski
    Abstract:

    List of DEG found in the contrast “mid-gestation over Antigestagen”. Shown are the following lists: (1–2) list of genes with p 

Alois Boos - One of the best experts on this subject based on the ideXlab platform.

  • Gene expression profiling of the canine placenta during normal and Antigestagen-induced luteolysis
    General and Comparative Endocrinology, 2019
    Co-Authors: Marta Nowak, Serhan Serhat Ay, Ewa Kautz, Hubert Rehrauer, Alois Boos, Murat Findik, Mariusz P Kowalewski
    Abstract:

    Abstract The domestic dog is the only domestic animal species that does not produce steroids in the placenta and instead relies on luteal steroids throughout pregnancy. Nevertheless, the canine placenta is highly responsive to steroids, and withdrawal of progesterone (P4) affects the feto-maternal unit, initializing the parturition cascade. Similar effects can be observed during Antigestagen-induced abortion. Here, aiming to provide new insights into mechanisms involved in the termination of canine pregnancy, next generation sequencing (NGS, RNA-seq) was applied. Placental transcriptomes derived from natural prepartum and Antigestagen-induced abortions were analyzed and compared with fully developed mid-gestation placentas. The contrast “prepartum luteolysis over mid-gestation” revealed 1973 differentially expressed genes (DEG). Terms associated with apoptosis, impairment of vascular function and activation of signaling of several cytokines (e.g., IL-8, IL-3, TGF-β) were overrepresented at natural luteolysis. When compared with mid-term, Antigestagen treatment revealed 135 highly regulated DEG that were involved in the induced luteolysis and showed similar associations with functional terms and expression patterns as during natural luteolysis. The contrast “Antigestagen-induced luteolysis over prepartum luteolysis” revealed that, although similar changes occur in both conditions, they are more pronounced during natural prepartum. Among P4-regulated DEG were those related to immune system and cortisol metabolism. It appears that, besides inducing placental PGF2α output, both natural and induced P4 withdrawal is associated with disruption of the feto-maternal interface, leading to impaired vascular functions, apoptosis and controlled modulation of the immune response. The time-related maturation of the feto-maternal interface needs to be considered because it may be clinically relevant.

  • Luteal ANGPT-TIE system during selected stages of pregnancy, and normal and Antigestagen-induced luteolysis in the dog.
    Reproduction (Cambridge England), 2018
    Co-Authors: Aykut Gram, Alois Boos, Miguel Tavares Pereira, Anna T. Grazul-bilska, Mariusz P Kowalewski
    Abstract:

    Abstract Rapid establishment of a vascular network is essential for normal functionality of the corpus luteum (CL). The early luteal phase is associated with increased expression of the VEGF system in canine CL. Acting in synchrony with angiopoietins (ANGPTs), VEGF system plays major roles in stabilization of blood vessels. However, the expression of the ANGPT system has not yet been investigated in the dog. Therefore, here, we investigated the luteal expression of ANGPT1, -2, and of their receptors TIE1 and -2, in pregnant dogs at selected time points during pregnancy and at normal and Antigestagen-induced luteolysis. Additionally, luteal cells from early CL were incubated with PGE2 and its effects on the ANGPT system were assessed. Whereas the luteal ANGPT1 was stable until mid-gestation, TIE1 was elevated post-implantation, their expression decreased toward prepartum luteolysis. The ANGPT2- and TIE2-mRNA did not vary during pregnancy. The ANGPT2/ANGPT1 ratio was elevated during prepartum luteolysis. PGE2 increased ANGPT2, but suppressed ANGPT1 levels. None of the ANGPT-system members was affected by Antigestagen treatment in mid-pregnancy. Localization of ANGPT1 was predominantly found in the tunica intima and media of vessels and ANGPT2 stained strongly in luteal cells. Both ANGPTs were localized in macrophages. TIE1 stained in the vascular tunica media, in luteal cells and macrophages, whereas TIE2 was colocalized with ANGPT1 in vascular components. In conclusion, high expression of ANGPT1 during the increased presence of VEGFA in early canine CL implies its contribution to vascular network development. The upregulation of the ANGPT2/ANGPT1 ratio during prepartum luteolysis indicates involvement of the ANGPT system in PGF2α-mediated vascular destabilization.

  • Transcriptome analysis reveals differences in mechanisms regulating cessation of luteal function in pregnant and non-pregnant dogs
    BMC Genomics, 2017
    Co-Authors: Sophie Zatta, Hubert Rehrauer, Alois Boos, Aykut Gram, Mariusz Pawel Kowalewski
    Abstract:

    Background In the domestic dog, corpora lutea (CL) are the only source of progesterone (P4), both in pregnant and non-pregnant cycles because there is no placental steroidogenesis. The absence of an endogenous luteolysin in absence of pregnancy results in long-lasting physiological pseudopregnancy, strongly contrasting with the acute luteolysis observed prepartum. The underlying biological mechanisms and the involvement of P4 signalling remain, however, not fully understood. Therefore, here, next-generation sequencing (RNA-Seq) was performed on CL from the late luteal phase and compared with normally luteolyzing CL collected at the prepartum P4 decrease. Results The contrast “luteal regression over luteolysis” yielded 1595 differentially expressed genes (DEG). The CL in late luteal regression were predominantly associated with functional terms linked to extracellular matrix ( p  = 5.52e-05). Other terms related to transcriptional activity ( p  = 2.45e-04), and steroid hormone signalling ( p  = 2.29e-04), which were more highly represented in late regression than during luteolysis. The prepartum luteolysis was associated with immune inflammatory responses ( p  = 2.87e-14), including acute-phase reaction ( p  = 4.10e-06). Immune system-related events were also more highly represented in CL derived from normal luteolysis ( p  = 7.02e-04), compared with those from dogs in which luteolysis was induced with an Antigestagen (1480 DEG in total). Additionally, the withdrawal of P4 at mid-gestation resulted in 92 DEG; over-represented terms enriched in Antigestagen-treated dogs were related to the inflammatory response ( p  = 0.005) or response to IL1 ( p  = 7.29e-05). Terms related to proliferation, e.g., centrosome organization ( p  = 0.002) and steroid metabolic processes ( p  = 0.001), prevailed at mid-gestation. Thereby, our results revealed the nature of luteotropic effects of P4 within canine CL. It appears that, even though they result in diminished steroidogenic output, the effect of Antigestagens is more related to the withdrawal of P4 support than to the PGF2alpha-related inflammatory reaction observed at physiological parturition. Conclusions We report the differential gene expression associated with maintenance and cessation of luteal function in pregnant and non-pregnant dogs. Based on the differentially expressed genes, we indicate functional pathways and gene networks that are potentially involved in the underlying endocrine and molecular mechanisms. This study establishes future research directions that may be helpful in understanding some of the clinical conditions, such as luteal insufficiency, associated with negative pregnancy outcome in dogs.

  • Additional file 6: of Transcriptome analysis reveals differences in mechanisms regulating cessation of luteal function in pregnant and non-pregnant dogs
    2017
    Co-Authors: Sophie Zatta, Hubert Rehrauer, Alois Boos, Aykut Gram, Mariusz Kowalewski
    Abstract:

    Venn-diagrams, combined results for Figs. 3 and 4. An overview of overlapping genes commonly expressed between the selected contrasts: (contrast 1) “luteal regression over luteolysis” and (contrast 2) “mid-gestation over Antigestagen”, or (contrast 1) “luteolysis over Antigestagen” and (contrast 2) “mid-gestation over luteolysis”. There are separate lists for each set threshold: genes expressed solely in either of the contrasts, and genes commonly expressed in both contrasts. (XLSX 67 kb

  • Additional file 4: of Transcriptome analysis reveals differences in mechanisms regulating cessation of luteal function in pregnant and non-pregnant dogs
    2017
    Co-Authors: Sophie Zatta, Hubert Rehrauer, Alois Boos, Aykut Gram, Mariusz Kowalewski
    Abstract:

    List of DEG found in the contrast “luteolysis over Antigestagen”. All genes detected with p 

Kowalewski, Mariusz P - One of the best experts on this subject based on the ideXlab platform.

  • Factors affecting the fate of the canine corpus luteum: Potential contributors to pregnancy and non-pregnancy
    'Elsevier BV', 2020
    Co-Authors: Papa, Paula C, Kowalewski, Mariusz P
    Abstract:

    The fate of the canine corpus luteum (CL) differs from that of other domestic species: beyond the extended luteal regression observed in both pregnant and non-pregnant cycles, active luteolysis is observed only in pregnant dogs. Luteal regression in the absence of pregnancy lacks a luteolytic trigger. The CL lifespan during pregnancy is around 60 days, as long as that of the cyclic CL. Although they are already available in the first half of diestrus, LH and especially prolactin (PRL) play a decisive luteotropic role from approximately day 25 post-ovulation onwards. Nevertheless, many locally-produced factors are orchestrated to ensure a fully functional CL, which in the bitch produces progesterone (P4), 17b-estradiol, and other local regulators. Recently, insulin has been described as another luteotropic factor in this species, able to increase glucose uptake in luteal cells and contribute to steroid biosynthesis. The locally-produced PGE2 is also a potent luteotropic factor in the first half of diestrus, promoting STAR expression, as are also proliferating, vasoactive- and immunomodulatory factors. These, in turn, all contribute to the formation and maintenance of the canine CL. Meanwhile PGF2a, produced by the utero-placental compartment, participates actively in triggering pre-partum luteolysis. Cytokines play different roles, either contributing as luteotropic or as acute inflammation molecules. So far, the one clinically most efficient mechanism of interrupting a pregnancy in the dog is to block P4 receptors, using an Antigestagen (e.g., aglepristone) in the second half of diestrus. To enhance the chances of pregnancy, however, several luteotropic factors could be used

  • Expression of insulin-like growth factor 1 and its receptor in preovulatory follicles and in the corpus luteum in the bitch
    Elsevier, 2018
    Co-Authors: Balogh Orsolya, Müller Linda, Boos Alois, Kowalewski, Mariusz P, Reichler, Iris M
    Abstract:

    In the bitch, ovarian follicular and corpus luteum (CL) development and function are regulated by gonadotropins as well as local factors, the role of which is especially important during the early CL phase of relative gonadotrophic independence. We assumed that insulin-like growth factor 1 (IGF1) has a paracrine/autocrine regulatory role in ovarian follicular and luteal function in the dog. To address our hypothesis, we studied gene and protein expression of IGF1 and its receptor (IGF1R) in preovulatory follicles and in the CL of pregnant and non-pregnant dogs, and following Antigestagen (aglepristone, progesterone receptor blocker) treatment in mid-gestation. Ovaries in the follicular phase were collected from five bitches. CL were collected on pregnancy Days 8–12 (pre-implantation), 18–25 (post-implantation), 35–40 (mid-gestation), at prepartum luteolysis, and 24 h and 72 h after aglepristone treatment in mid-gestation (n = 3–5 per group). From non-pregnant bitches, CL were collected on Days 5, 15, 25, 35, 45, 65 after ovulation (n = 4–5 per group). Semi-quantitative real-time (TaqMan) PCR and immunohistochemistry were applied. IGF1 immunostaining in preovulatory follicles seemed stronger in theca interna than granulosa cells. IGF1R signals appeared more intense in granulosa cells at the apical part of mural folds. In pregnant dogs, luteal IGF1 mRNA expression decreased significantly from pre-implantation to prepartum luteolysis, while IGF1R expression increased at prepartum luteolysis. Aglepristone treatment in mid-gestation had no effect on IGF1 and IGF1R mRNA levels. In non-pregnant bitches, highest IGF1 mRNA concentrations were found in the early CL and decreased by Days 45 and 65, while IGF1R expression did not change. In the CL of pregnant bitches, signals for IGF1 and IGF1R in luteal cells were strongest at pre- and post-implantation and weakest at prepartum luteolysis. IGF1 and IGF1R immunostaining was also detected in macrophages and in blood vessels. In conclusion, IGF1 may have a paracrine or autocrine role in granulosa and theca interna cells in preovulatory follicles. As IGF1 was highest represented in early luteal stages in pregnant and non-pregnant bitches, this may support a role for IGF1 in steroid synthesis, angiogenesis and cell proliferation as well as in immune function in the early canine CL. The unaffected mRNA levels after aglepristone treatment may support that IGF1 is not directly regulated by local progesterone in an auto- or paracrine manner

  • Luteal and hypophyseal expression of the canine relaxin (RLN) system during pregnancy: Implications for luteotropic function
    Public Library of Science (PLoS), 2018
    Co-Authors: Nowak Marta, Boos Alois, Kowalewski, Mariusz P
    Abstract:

    By acting through its receptors (RXFP1, RXFP2), relaxin (RLN) exerts species-specific effects during pregnancy; possible luteotropic effects through stimulation of prolactin (PRL) release have been suggested. In the domestic dog (Canis lupus familiaris) serum PRL increases in pregnant bitches shortly after RLN appears in the circulation, and a possible functional relationship between the RLN and the PRL systems in regulating progesterone secretion has been implied. Therefore, here (Study 1) the luteal expression and localization of the RLN system was investigated by immunohistochemistry using custom-made antibodies and semi-quantitative PCR, at selected time points during gestation: pre-implantation (d. 8-12), post-implantation (d. 18-25), mid-gestation (d. 35-40) and at normal and Antigestagen-induced luteolysis. Further, (Study 2) hypophyseal expression of the RLN system and its spatial association with PRL was assessed. Luteal expression of RLN, but not of its receptors, was time-dependent: it increased significantly following implantation towards mid-gestation and decreased at prepartum. Antigestagen treatment resulted in downregulation of RLN and RXFP2. Whereas RLN was localized in steroidogenic cells, RXFP1 and RXFP2 also stained strongly in macrophages and vascular endothelial cells. The RLN system was detected in the canine adenohypophysis and was co-localized with PRL in hypophyseal lactotrophs. The intraluteal RLN seems to be involved in regulating the canine corpus luteum (CL) in a time-dependent manner. The presence of RLN family members in the adenohypophysis implies their possible involvement in regulating the availability of PRL and other pituitary hormones

  • Cellular localization, expression and functional implications of the utero-placental endothelin system during maintenance and termination of canine gestation
    Japanese Society of Animal Reproduction, 2017
    Co-Authors: Gram Aykut, Boos Alois, Kowalewski, Mariusz P
    Abstract:

    Utero-placental (Ut-Pl) angiogenesis and blood flow are fundamental for successful outcome of pregnancy. They are controlled by numerous vasodilator and vasoconstrictor systems such as endothelins (EDNs) and the renin angiotensin system. Dogs possess an invasive type of placentation, classified as endotheliochorial. Despite increasing knowledge regarding canine Ut-Pl function, little information exists on uterine and placental vascular activity during initiation, maintenance and termination of pregnancy in this species. The current study investigated expression of EDNs and their receptors (EDNRA and EDNRB) in the pre-implantation uterus and Ut-Pl compartments during gestation and at normal parturition, as well as in mid-pregnant dogs treated with the Antigestagen aglepristone. The Ut-Pl mRNA expression of EDN1 and EDNRA was constant until mid-gestation and increased significantly during prepartum luteolysis. In contrast, EDN2 was highest pre-implantation and decreased following placentation, remaining low thereafter. Expression of the EDN-activating enzyme ECE1 and mRNA of EDNRB increased towards mid-gestation and was further elevated at prepartum luteolysis. Antigestagen treatment resulted in increased levels of EDN1 and EDNRA. At the cellular level, the uterine expression of EDN1, ECE1 and EDNRB was found predominantly in the endometrial surface and glandular epithelial cells; uterine signals for EDNRA were weak. In Ut-Pl all targets were mainly localized in the placenta fetalis, with syncytiotrophoblast staining stronger for ECE1 and EDNRB. In contrast, EDNRA stained strongly at the base of the placental labyrinth. Expression and localization of EDNs (EDN1, -2), EDN receptors and ECE1 in the placenta fetalis suggests their involvement in the trophoblast invasion and proliferation

  • Cells expressing CD4, CD8, MHCII and endoglin in the canine corpus luteum of pregnancy, and prepartum activation of the luteal TNFα system
    Elsevier, 2017
    Co-Authors: Nowaczyk, Renata M, Boos Alois, Gram Aykut, Jursza-piotrowska Ewelina, Siemieniuch, Marta J, Kowalewski, Mariusz P
    Abstract:

    In the dog, knowledge about involvement of the immune system in controlling luteal function is restricted to observations showing a time-dependent invasion of immune cells into the corpus luteum (CL) of non-pregnant bitches. Therefore, this study investigated the presence of CD4-, CD8-, MHCII- and endoglin-expressing cells in CL collected throughout pregnancy from pre-implantation until prepartum luteolysis. Immunohistochemistry and semi-quantitative RT-PCR were applied. The time-dependent expression of CD4, CD8 and endoglin was more strongly related to formation of the CL, whereas MHCII was induced during luteolysis. Next, the luteal expression of TNFα and its receptors, TNFR1 and TNFR2, was analyzed in non-pregnant dogs between days 5-65 after ovulation and during pregnancy. Moreover, the effects of progesterone withdrawal were investigated in mid-pregnant dogs treated with an Antigestagen aglepristone. The TNFα system was induced in the early CL of non-pregnant dogs. In pregnant dogs, expression of TNFα did not vary much, contrasting with increased expression of both receptors in the post-implantation period and significantly decreased expression at mid-gestation; prepartum luteolysis was characterized by increased TNFR2 expression. Apart from the downregulated expression of TNFR1, the changes observed following Antigestagen treatment resembled those observed during normal prepartum luteolysis. A modulatory function of the TNFα system during formation of the canine CL is suggested, possibly related to the strong accompanying vascularization and luteal infiltration with activated macrophages. Contrasting with the slow luteal regression in non-pregnant dogs, in pregnant animals the upregulation of TNFR2 expression during prepartum luteolysis implies functional involvement of the TNFα system during that time