Browsing by Author "Dilly, Marc"
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Item Effect of progesterone receptor blockage in late pregnant cows on placental histomorphology and maternal prostaglandin F2 alpha metabolite (PGFM) levels(Wiley, 2010-02) Shenavai, Sima; Dilly, Marc; Pfarrer, Christiane; Kindahl, Hans; Hoffmann, B.; Schuler, Gerhard; Özalp, Rabia Gözde; İntaş, Kamil Seyrek; Çalışkan, Çağlar; Uludağ Üniversitesi/Veterinerlik Fakültesi/Klinik Bilimler Bölümü.; 0000-0003-4694-6937; AAE-3607-2019; AAH-7292-2019Item Expression of matrix metalloproteinase (MMP)-2, MMP-14 and tissue inhibitor of matrix metalloproteinase (TIMP)-2 during bovine placentation and at term with or without placental retention(Elsevier, 2011-04-01) Dilly, Marc; Hambruch, Nina; Shenavai, Sima; Schüler, Gerhard; Froehlich, R.; Häeger, Jan Dirk; Pfarrer, Christiane D.; Özalp, Gözde Rabia; Uludağ Üniversitesi/Veterinerlik Fakültesi/Kadın Hastalıkları ve Doğum Anabilim Dalı.; 0000-0003-4694-6937; AAE-3607-2019; 23985710500Matrix metalloproteinases (MMPs) and counteracting tissue inhibitors of metalloproteinases (TIMPs) are balancing extracellular matrix (ECM) formation and degradation. The latter is believed to be an important aspect for the detachment of fetal membranes postpartum when loosening the feto-matemal connection which is a prerequisite to avoid placental retention a common disease in cows leading to considerable economic loss. Membrane-type (MT) MMPs have been suggested as potential activators controlling ECM remodelling. In particular, MT1-MMP (MMP-14) is able to degrade ECM substrates and activate MMP-2 through binding TIMP-2 at the cell surface. Since the connection between the trophoblast and the maternal caruncular epithelium is supported by integrin receptors bound to ECM, we hypothesize that impaired modulation of the ECM by TIMPs/MMPs participates in the aetiology of bovine retained fetal membranes. To analyse this involvement, placentomes were collected from cows after term parturition and timely release of fetal membranes (n = 4) and cows with retained fetal membranes after various treatments for the induction of parturition using progesterone antagonist (aglepristone), PGF(2 alpha) analogue, glucocorticoid, and after elective caesarean sections (each group n = 3). The expression of MMP-14, MMP-2 and of TEMP-2 was examined by real-time-PCR, irnmunohistochemistry, Western blot and zymography. The relative mRNA expression levels of MMP-14 remained unchanged, while the expression levels of TIMP-2 and MMP-2 partly increased in animals with induced parturition and retention of fetal membranes compared to animals without placental retention. MMP-14 protein was expressed in cells of the uninucleated trophoblast, the fetal mesenchyme and maternal stoma. TIMP-2 was present exclusively in trophoblast giant cells, while MMP-2 could be detected in uninucleated trophoblast cells and the fetal mesenchyme. The presence of the activated enzyme was confirmed by zymography. In conclusion, MMP-14, MMP-2 and TIMP-2 are co-localized in the fetal compartment and therefore could influence the timely release of fetal membranes in cattle.Item Investigations into the mechanisms controlling parturition in cattle(Bioscientifica, 2012-08) Shenavai, Sima; Preissing, Susanne; Hoffmann, Bernd; Dilly, Marc; Pfarrer, Christiane; Schuler, Gerhard; Özalp, Gözde R.; Çalışkan, Çağlar; Seyrek, Kamil İntaş; Uludağ Üniversitesi/Veteriner Fakültesi/Doğum ve Jinekoloji Anabilim Dalı.; 0000-0003-4694-6937; AAH-7292-2019; AAE-3607-2019; 23985710500; 23984353800; 6603409870A pronounced increase in fetal cortisol concentrations stimulating an increase in estrogen production at the expense of progesterone precursors in the placenta, luteolysis, and progesterone withdrawal is considered as a key event during the complex signal cascade leading to the initiation of parturition in cattle. However, there are many questions concerning the exact functional and/or temporal relationships between these individual processes which finally result in the expulsion of the calf and the timely release of the placenta. Thus, parturition was induced in 270-day pregnant cows using the progesterone receptor blocker aglepristone (group AG, n=3), the prostaglandin F-2 alpha analog cloprostenol (group PG, n=4), and the glucocorticoid dexamethasone (group GC, n=4) to characterize the effect on maternal steroid and prostaglandin levels and to identify immediate subsequent changes in placental morphology and gene expression as compared with untreated controls sampled on day 272 (group D272, n=3) and cows during normal parturition (group NT, n=4). All calves of the treatment groups were born on days 271-272, whereas gestational length in NT cows was 280.5 +/- 1.3 days. However, none of the treatments significantly induced the prepartal remodeling of placentomes characterized by a decline in trophoblast giant cells and reduction of the caruncular epithelium. Data on placental CYP17 and COX2 expression confirm that these key enzymes are upregulated by GC, whereas placental aromatase expression was not affected by any treatment. Maternal progesterone and prostaglandin profiles suggest differential effects of the treatments on luteal function and placental or uterine prostaglandin production. The results provide new information on the initiation of parturition in cattle but raise many new questions.Item Investigations on the signal cascade initiating parturition in cattle(Wiley, 2011-02) Shenavai, Sima; Preissing, Susanne; Dilly, Marc; Pfarrer, C.; Hoffmann, B.; Schuler, G.; Özalp, Gözde Rabia; Çalışkan, Çağlar; İntaş, Kamil Seyrek; Uludağ Üniversitesi/Veterinerlik Fakültesi/Kadın Hastalıkları ve Doğum Anabilim Dalı.; 0000-0003-4694-6937; AAE-3607-2019; AAH-7292-2019Item Matrix metalloproteinase 2 (MMP-2) may be activated by binding of tissue inhibitor of matrix metalloproteinase 2 (TIMP-2) to MMP-14 in bovine placentomes(Wiley, 2009-02) Dilly, Marc; Shenavai, Sima; Hambruch, Nina; Schuler, Gerhard; Pfarrer, Christiane; Özalp, Gözde Rabia; İntaş, Kamil Seyrek; Uludağ Üniversitesi/Veterinerlik Fakültesi/Kadın Hastalıkları ve Doğum Anabilim Dalı.; 0000-0003-4694-6937; AAH-7292-2019; AAE-3607-2019Item Persistence of placental progesterone production in parturient cows is not a major factor in the etiology of retained fetal membrane(Wiley, 2009-02) Shenavai, Sima; Dilly, Marc; Pfarrer, Chistiane; Hoffmann, B.; Schuler, Gerhard; Özalp, Gözde Rabia; İntaş, Kamil Seyrek; Çalışkan, Çağlar; Uludağ Üniversitesi/Veterinerlik Fakültesi/Kadın Hastalıkları ve Doğum Anabilim Dalı.; 0000-0003-4694-6937; AAH-7292-2019; AAE-3607-2019Item Use of the progesterone (P4) receptor antagonist aglepristone to characterize the role of P4 withdrawal for parturition and placental release in cows(Bioscientifica, 2010-10) Shenavai, Sima; Hoffmann, Bernd; Dilly, Marc; Pfarrer, Christiane D.; Schüler, Gerhard; Özalp, Gözde Rabia; Çalışkan, Çağlar; Seyrek İntaş, Kamil; Uludağ Üniversitesi/Veterinerlik Fakültesi/Doğum ve Jinekoloji Bölümü.; 0000-0003-4694-6937; AAH-7292-2019; AAE-3607-2019; 23985710500; 23984353800; 6603409870In late pregnant cows, progesterone (P-4) is mainly of luteal origin. However, the trophoblast may provide high local P-4 concentrations in the uterus. To test for the importance of a complete P-4 withdrawal for parturition-related processes and placental release, the P-4 receptor (PGR) blocker aglepristone (Ap) was administered to three cows on days 270 and 271 of pregnancy. A complete opening of the cervix was observed 46.5 +/- 7.3 h after the start of treatment. However, expulsion of the calves was impaired obviously because of insufficient myometrial activity, and placental membranes were retained for at least 10 days. Measurement of P-4 concentrations indicated that PGR blockage induced luteolysis. To investigate the role of P-4 withdrawal for the prepartal tissue remodeling of the placentomes, the caruncular epithelium was evaluated by morphometry, and the percentage of trophoblast giant cells (TGCs) relative to the total number of trophoblast cells were assessed. Caruncular epithelium in Ap-treated cows (D272 + Ap) was immature (30.5 +/- 3.3%) and not different from untreated controls (elected cesarean section (CS) on day 272; D272-CS; 31.5 +/- 1.4%), whereas it was significantly reduced at normal term (D280.5 +/- 1.3; 21.0 +/- 6.1%; P=0.011). Correspondingly, the percentage of TGCs were 20.1 +/- 1.4 in D272 + Ap, 22.1 +/- 4.8 in D272-CS, and 9.8 +/- 3.9 at term (P=0.001). No effect was detected on placental estrogen synthesis. The results showed that in late pregnant cows, P-4 withdrawal only induces a limited spectrum of the processes related to normal parturition and is not a crucial factor for the prepartal tissue remodeling in placentomes and the timely release of the placenta.