Poly(ADP-Ribose) Glycohydrolase in Bovine Retained and Not Retained Placenta

Poly(ADP-ribose) glycohydrolase (PARG) is the enzyme which degrades poly(ADP-ribose) polymers synthesized by poly(ADP-ribose) polymerase (PARP). Both enzymes are activated in response to different stimuli like oxidative stress and are involved in DNA repair processes. The retention of bovine foetal membranes (RFM) is supposed to be connected with oxidative stress conditions. The aim of the study was to detect the presence of PARG protein in bovine placenta in order to find the relationship between the process of releasing, retaining placenta and DNA repair. Placentomes, collected alter spontaneous delivery or caesarian section were divided into maternal as well as foetal part of placenta, homogenized and subjected to electrophoresis. Animals were divided into six groups as follows: A--caesarian section before term with RFM; B--caesarian section before term without RFM; C--spontaneous delivery at term with RFM; D--spontaneous delivery at term without RFM; E--caesarian section at term with RFM; F--caesarian section at term without RFM. PARG protein was detected in nitrocellulose membranes using commercially available bovine anti-PARG antibody and Western blotting technique. Single bands referred to bovine PARG standard were observed in all examined tissues as well as in human placenta used as the control of procedure. In addition, the intensity of staining was stronger in retained than properly released term placenta and in foetal than in maternal part of the placenta. These results may suggest the differences in enzyme protein content and careful conclusions can be drawn that the activities of PARG may be altered between compared groups of animals. It may confirm the presence of oxidative stress conditions and their consequences on metabolic pathways, the content of biologically active substances and processes of proper releasing placenta. Further experiments on PARG activity in bovine foetal membranes with respect to proper and improper placental release are necessary.