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Immune system activation has been observed during endurance exercise, but its relevance is largely unclear. We evaluated urinary neopterin excretion in an athlete competing in the Race Across America (RAAM), to determine whether neopterin excretion would indicate that immune system activation occurs during extreme endurance sport. Urinary samples were collected at the day before the race, during the whole RAAM, and, without a physical strain, seven days after the race. Neopterin normalized to creatinine concentration was determined by reversed-phase high-pressure liquid chromatography (HPLC). Data were analysed by repeated-measured analysis of variance (ANOVA). In the athlete, urinary neopterin concentration started to increase consistently after the start of the race until day four, followed by a decline thereafter, reaching values close to the starting value. The lowest average neopterin concentration was observed at day seven; this concentration was significantly lower than mean values at days 2- 6 (all p

In a recent study we could show that neopterin inhibits nitric oxide-induced apoptosis in ovarian carcinoma cells. This may provide an explanation for the correlation between increased levels of neopterin derivatives and the unfavorable prognosis in patients with ovarian cancer that has been described in the literature. To obtain additional information on the mode of action of neopterin derivatives within the tumor environment, we studied the effects of neopterin (100 and 1000 μΜ) and 7,8-dihydroneopterin (100, 500, and 1000 μΜ) on mitochondrial dehydrogenase activity in three different ovarian carcinoma cell lines (2774, HOC-1, and OVCAR-3). 7,8-dihydroneopterin was an effective stimulus of mitochondrial enzyme turnover rate in any cell culture model under investigation. This suggests that the pteridine compound stabilizes tumor cell viability and therefore acts as a promotor of tumor growth. In contrast to 7.8-dihydroneopterin, neopterin did not affect mitochondrial dehydrogenases in 2774, HOC-7, or OVCAR-3 cells. However, in HOC-7 and OCVAR-3, neopterin was found to antagonize the stimulating effects of 7,8-dihydroneopterin. This might be due to the different impact of both pteridine compounds on the redox status in these cells. Our new data provide further evidence of distinct biochemical effects of neopterin derivatives in ovarian carcinoma cells. Neopterin and 7,8-dihydroneopterin may be involved in separate stages of cellular changes that lead to malignancy or promote tumor progression.

Increases in serum neopterin concentrations are a regular finding in patients with ovarian cancer. The strong correlation between neopterin and tumor progression might be explained by a direct influence of the pteridine compound on tumor cell growth. In the present study we investigated whether neopterin affects the production of the angiogenic promotors vascular endothelial growth factor (VEGF) and erythropoietin (EPO) in the human ovarian carcinoma cell line OVCAR-3. VEGF and EPO gene expression were detected via RT-PCR. and a possible involvement of hypoxiainducible factor-1 was assessed by electrophoretic mobility shift assays. Neopterin amplified the hypoxia-induced VEGF and EPO gene expression as well as protein synthesis in a concentration-dependent manner. In addition, generation of both VEGF and EPO could be detected following incubation of cells with neopterin under normoxic conditions, too. Neopterin-induced synthesis of VEGF and EPO was preceeded by a stimulation of hypoxiainducible factor-1 uptake into the nucleus of OVCAR-3 cells. From these data we conclude that neopterin acts as a mediator of angiogenesis. Stimulation of VEGF and EPO generation in ovarian carcinoma cells may promote vascularization of the malignant tissue and thus tumor growth and development.

In a Number of malignant diseases including ovarian carcinomas, increased serum or urine levels of neopterin serve as a valuable marker for the state of activation of the cellular immune system. Reported correlations benveen elevated neopterin concentrations and shorter survival time of the tumor host might be explained by direct biochemical actions exhibited by the pteridine compound. In the present study, we investigated the influence of neopterin on inducible nitric oxide synthase (iNOS) gene expression in two ovarian carcinoma cell lines. Qualitative and quantitative analyses of iNOS as well as measurements of nitric oxide (NO) metabolites in the cell supernatant revealed an inhibitory effect of neopterin (1000 11M) on NO generation induced by a combination ofinterferon-γ (100 U/ml), tumor necrosis factor-a (500 U/ml), and interleukin-1β (10 U/ml). Since NO is most likely involved in apoptotic cell death in ovarian carcinoma cells, it is conceivable that suppression of NO synthesis represents a biochemical mechanism mediated by neopterin that is advantageous to tumor progression and thus harmful to the host.

Robinow (fetal face) syndrome is a rare inherited multisystem disorder featuring mesomelic or acromesomelic limb shortening, facial and spinal deformities, hypoplastic genitalia, kidney disease and congenital heart defects. We report the anaesthetic management of a patient with Robinow syndrome presenting for elective surgery and review specific issues of interest in the perioperative workup. [ABSTRACT FROM AUTHOR]