<strong>Paper Title</strong><br> Influence of Organism Aging on Metabolomic Profile Created from Blood<br> <br> <strong>Abstract</strong><br> Aging (senescence) represents probably the greatest disease of all. There is very little known about it and it is indeed inevitable. There are generally two main explanations of aging – genetic programming and oxidative damage. The both alternatives are widely explored via number or variously designed animal studies. Our model organism were birds (barn swallows) because of their very fast metabolism that is similar to the human one. The analytical methods based on liquid chromatography combined with mass spectrometry were developed to monitor levels of antioxidants and to create age-dependent metabolic profile. There was found out, that in the period of three years the amount of antioxidants drops by minimally 10%. Moreover, the amount of biomarkers of oxidative damage to organism rises over the same period of time by 15% in average. These findings support the theory of oxidative damage as a key mechanism of aging. Keywords - Aging, oxidative stress, antioxidants, metabolomics, senescence, mass spectrometry