I Oborna

Publications (2)8.95 Total impact

• Article: Increased lipid peroxidation and abnormal fatty acid profiles in seminal and blood plasma of normozoospermic males from infertile couples.

  I Oborna, G Wojewodka, J B De Sanctis, H Fingerova, M Svobodova, J Brezinova, M Hajduch, J Novotny, L Radova, D Radzioch
  [show abstract] [hide abstract]
  ABSTRACT: Reactive oxygen species (ROS) are essential for sperm function. However, excessive ROS production can impair sperm function and might be a factor contributing to male infertility. We investigated the levels of arachidonic acid (AA) and docosahexaenoic acid (DHA) as well as lipid peroxidation, as represented by thiobarbituric acid reactive species (TBARS), in blood and seminal plasma of 38 normozoospermic males from infertile couples (NSI-males), compared with that of 17 fertile volunteers (FV-males). TBARS levels in blood and seminal plasma were higher in NSI-males than in FV-males (P < 0.0002, P < 0.0003, respectively), as were AA levels (P < 0.0003, P < 0.00004, respectively). On the contrary, the blood and seminal plasma levels of DHA were lower in NSI-males than in FV-males (P < 0.02 and P < 0.05, respectively). The AA/DHA ratios in blood and seminal plasma were higher in NSI-males than in FV-males (P < 0.003, P < 0.0007, respectively). Significant correlations between seminal and blood plasma levels of TBARS (P < 0.0001, r = 0.548), AA (P < 0.0001, r = 0.571) and DHA (P < 0.0001, r = 0.506) were found. Our data provide new insight into lipid metabolism in male infertility and indicate that systemic oxidative stress resulting in increased lipid peroxidation and an altered fatty acid profile may be, at least in part, responsible for infertility even in normozoospermic males.
  Human Reproduction 11/2009; 25(2):308-16. · 4.47 Impact Factor
• Article: Endometrial expression of the estrogen-sensitive genes MMP-26 and TIMP-4 is altered by a substitution protocol without down-regulation in IVF patients.

  R Pilka, I Oborna, V Lichnovsky, P Havelka, H Fingerova, P Eriksson, S Hansson, B Casslén
  [show abstract] [hide abstract]
  ABSTRACT: The aim of this study was to analyse the effects of an estradiol (E(2))-progesterone substitution protocol on the endometrial expression of estrogen-sensitive genes during the peri-implantation period. Peripheral blood and endometrial biopsies were obtained from 13 infertile women both in a natural cycle (NC), on days 5 and 7 after ovulation (NC5, NC7), and in an artificial (substituted) cycle (AC), on days 5 and 7 of progesterone addition (AC5, AC7). Estrogen receptor-alpha (ERalpha) and progesterone receptor (PR) were assayed by immunohistochemistry. Matrix metalloproteinase-26 (MMP-26) mRNA and tissue inhibitor of metalloproteinase-4 (TIMP-4) mRNA were semiquantitatively assessed in tissue sections using in situ hybridization (ISH) and quantified in tissue extracts using real-time PCR. Levels of both E(2) and progesterone were higher in the peripheral blood in AC than in NC. Also on day AC5, expressions of ERalpha, PR and MMP-26 mRNA (focally) were increased in the epithelium and TIMP-4 mRNA in the stroma. Expression levels of these genes dropped significantly between AC5 and AC7, but not between NC5 and NC7. Abnormally high levels in AC5 samples suggest overstimulation with E(2), and the rapid decrease between AC5 and AC7 suggests overstimulation with progesterone. In ACs, increased levels of E(2) in the blood exaggerate the endometrial expression of estrogen-sensitive genes, whereas higher levels of progesterone in the blood in the secretory phase exaggerate the drop in expression of these genes. Dramatic variations in the gene expression may not be optimal for the implantation process.
  Human Reproduction 01/2007; 21(12):3146-56. · 4.47 Impact Factor