Bernhard Ugele

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Human trophoblasts depend on the supply of external precursors, such as dehydroepiandrosterone-3-sulfate (DHEA-S) and 16 alpha-OH-DHEA-S, for synthesis of estrogens. The aim of the present study was to characterize the uptake of DHEA-S by isolated mononucleated trophoblasts (MT) and to identify the involved transporter polypeptides. The kinetic analysis of(More)
Human organic anion transporter 4 (hOAT4) is located at the apical membrane of proximal tubule cells and involved in renal secretion and reabsorption of endogenous substances as well as many drugs and xenobiotics. This study reevaluated the physiologic role, transport mode, and driving forces of hOAT4. 6-Carboxyfluorescein (6-CF) uptake into HEK293 cells(More)
BACKGROUND We recently identified agonistic autoantibodies directed against the angiotensin AT1 receptor (AT1-AA) in the plasma of preeclamptic women. To elucidate their role further, we studied the effects of AT1-AA on reactive oxygen species (ROS), NADPH oxidase expression, and nuclear factor-kappaB (NF-kappaB) activation. METHODS AND RESULTS We(More)
Organic anion-transporting polypeptides (OATPs) are a family of multispecific carriers that mediate the sodium-independent transport of steroid hormone and conjugates, drugs, and numerous anionic endogenous substrates. We investigated whether members of the OATP gene family could mediate fetal-maternal transfer of anionic steroid conjugates in the human(More)
Human trophoblasts depend on the supply of external precursors such as dehydroepiandrosterone-3-sulfate (DHEA-S) and 16alpha-OH-DHEA-S for synthesis of estrogens. Recently, we have characterized the uptake of DHEA-S by isolated mononucleated trophoblasts and identified different transporter polypeptides involved in this process. Immunohistochemistry of 1st(More)
AbstractDifferentiation of human placental villous trophoblast includes syncytial fusion of cytotrophoblast forming syncytiotrophoblast. Early stages of the apoptosis cascade were described to be involved in this differentiation process. We investigated the role of the initiator caspase 8 in syncytial fusion in vitro, cultivating placental villous explants(More)
The results are summarized in Table 1. The baseline absorbance of untreated plasma samples was significantly higher (0.106 6 0.076) than that of plasma samples treated with PEG (0.007 6 0.003; t 5 5.95; P ,0.001). There were no significant differences between the recovered ICG concentrations and the expected values at any of the four dye concentrations.(More)
Soy isoflavones (IF) are phytoestrogens, which interact with estrogen receptors. They are extensively metabolized by glucuronosyltransferases and sulfotransferases, leading to the modulation of their estrogenic activity. It can be assumed that this biotransformation also has a crucial impact on the uptake of IF by active or passive cellular transport(More)
Dehydroepiandrosterone (DHEA) and its sulfate (DHEAS) are suggested to be important neurosteroids. We investigated steroid sulfatase (STS) in human temporal lobe biopsies in the context of possible cerebral DHEA(S) de novo biosynthesis. Formation of DHEA(S) in mature human brain tissue has not yet been studied. 17 alpha-Hydroxylase/C17-20-lyase and(More)
Periportal and perivenous hepatocytes were isolated from rat liver by digitonin/collagenase perfusion for investigating the acinar distribution of bile acid synthesis. The specific activity of cholesterol 7 alpha-hydroxylase (EC 1.14.13.17) was 7.9-fold higher in perivenous cells than in periportal hepatocytes. Mass production of bile acids differed(More)