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Why Should a Single Nutrient – Glutamine - Improve Outcome The Glutamine and Glutamine-dipeptide story Narrated by Peter FüRST MD, PhD University Bonn Institute Nutritional Science Beijing, February 29, 2004 A Piece of History 1886 - A newly discovered substance found in the proteins from lupine and almond (conglutin) Ritthausen J für Praktische Chemie 1883 – The first description Schulze Bosshard “über Glutamine” 1914 – The first hint of presence and function in the human organism Thierfelder Sherwin 1934 - In vitro Glutamine synthesis. Definition of glutaminase catalyzing deamidation of glutamine in tissues Krebs et al The importance of glutamine- an early statement - ? ... most amino acids have multiple functions, but glutamine appears to be the most versatile ...“ Sir Hans Krebs, 1980 Glutamine – the ?pop-star“ of the 20th century Scientific papers 13.096* Nutrition research 1.021 Metabolism 509 Parenteral application 322 Published during the past 10 years! The Body Pool of Glutamine The most prevalent free proteic amino acid In extracellular fluid: 25% In intracellular fluid : 60% High transmembrane gradient over the cell membrane approximately 34:1 (intra/extracellular) Glutamine – Functions in Metabolism Important intermediate in metabolic pathways Precursor for the synthesis of purines, pyrimidines, nucleotides, amino sugars;main substrate for renal ammoniagenesis (regulation of acid-base balance) Nitrogen transporter between tissues and regulator of amino acid homeostasis The major metabolic fuel for the mucosa and rapidly proliferating cells (immune system) Bergstr?m et al. 1974, Meister 1983, Windmueller 1982, Souba 1991, Newsholme 1990 Glutamine : A key substrate for the splanchnic bed The splanchnic bed regulat