During pregnancy the alterations of kynurenine and tryptophan metabolism play an important role in local signalling and the prevention of fetal rejection. The aim was to investigate urinary levels of kynurenine and tryptophan during physiological pregnancy, and to determine their stability in urine during sample storage at different conditions. Urinary samples were obtained from 73 healthy pregnant women (median age 31 years), during the 1st, 2nd, and 3rd trimesters and from 42 healthy non-pregnant women (median age 30 years). Liquid chromatography methods using selective and sensitive mass spectrometry detection were used for analysis. Urinary neopterin, kynurenine, and tryptophan increased during the pregnancy and in comparison to the non-pregnant women. No correlation of the analytes with gestation age within each trimester and among the different analytes was observed. Kynurenine and tryptophan were stable in urine for 14 days at 4 °C, 6 months at - 22 °C, and 12 months at - 84 °C. Present results demonstrate differences in urinary concentrations of kynurenine, tryptophan, and neopterin between women with physiological pregnancy and healthy women. Simultaneous determination of kynurenine, tryptophan and neopterin may be explored in the disorders of pregnancy in future investigations.

• Klíčová slova
• HPLC-MS/MS, Healthy pregnancy, Stability study, Urinary kynurenine, Urinary tryptophan,
• MeSH
• chromatografie kapalinová MeSH
• dospělí MeSH
• kynurenin * moč   MeSH
• lidé MeSH
• mladý dospělý MeSH
• neopterin * moč   MeSH
• těhotenství MeSH
• tryptofan * moč   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladý dospělý MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kynurenin * MeSH
• neopterin * MeSH
• tryptofan * MeSH

Determining the age of free-living insects, particularly of blood-sucking species, is important for human health because such knowledge critically influences the estimates of biting frequency and vectoring ability. Genetic age determination is currently not available. Pteridines gradually accumulate in the eyes of insects and their concentrations is the prevailing method. Despite of their stability, published extractions differ considerably, including for standards, for mixtures of pteridines and even for light conditions. This methodological inconsistency among studies is likely to influence age estimates severely and to hamper their comparability. Therefore we reviewed methodological steps across 106 studies to identify methodological denominators and results across studies. Second, we experimentally test how different pteridines vary in their age calibration curves in, common bed (Cimex lectularius) and bat bugs (C. pipistrelli). Here we show that the accumulation of particular pteridines varied between a) different populations and b) rearing temperatures but not c) with the impact of light conditions during extraction or d) the type of blood consumed by the bugs. To optimize the extraction of pteridines and measuring concentrations, we recommend the simultaneous measurement of more than one standard and subsequently to select those that show consistent changes over time to differentiate among age cohorts.

• MeSH
• chromatografie kapalinová metody   MeSH
• hmyz - vektory MeSH
• oči metabolismus   MeSH
• pteridiny analýza   izolace a purifikace   metabolismus   MeSH
• stárnutí genetika   metabolismus   MeSH
• štěnice genetika   metabolismus   MeSH
• tandemová hmotnostní spektrometrie metody   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• pteridiny MeSH