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Glutamine and vitamin E may prevent hepatic ischemia-reperfusion (I/R) injuries. Our aim was to investigate the effects of glutamine, either alone or combined with vitamin E, against I/R in the isolated perfused rat liver.Four groups of 8 livers from male Sprague-Dawley rats were isolated and submitted to a 45-min no-flow ischemia and reperfusion in the presence of alanine 2 mM, alanine 2 mM plus vitamin E 150 microM, Alanyl-Glutamine (AlaGln) 2 mM, or AlaGln 2 mM plus vitamin E 150 microM. Six non-perfused livers were studied in parallel. Liver function, metabolic parameters, oxidative stress and inflammatory parameters have been studied.AlaGln was rapidly cleared from the perfusate (436+/-41 nmol min(-1) g(-1)) and lowered transaminase release during reperfusion (ALT: -59%), significantly so in the AlaGln+Vit E group (ALT: -65%, p0.05). The association of glutamine with vitamin E led to lower degrees NO (-83%, p0.05) production, better preserved hepatic glutathione content and, as with vitamin E alone, preserved hepatic vitamin A and significantly decreased malondialdehyde (-85%, p0.05).Both glutamine, by attenuating inflammatory response, and vitamin E, via its antioxidative properties, showed complementary protective effects against I/R-induced hepatic injury. These data emphasize the potential benefit of combining glutamine and vitamin E supplementation in hepatic I/R injury.

reports. The likely requirements for intravenous amino acids were clearly spelt out and numerous commercial preparations (mostly for adults) became available in Europe. The composition of these preparations, however, was mainly based on oral requirement data in healthy man. The major nutrition efforts were directed to improve tolerance of the nitrogen load in the presence of illness rather than to provide specific nutrients for individual organs or tissues. At most instances, the efficacy of an amino acid therapy was monitored in blood (plasma). However, as shown over the past 20 years, changes in plasma-free amino acid concentrations may parallel those in intracellular compartment, but they frequently differ either quantitatively or qualitatively. The importance of this area was recognised early in the history of ESPEN when in the 1984 Arvid

Background & Aims: Glutamine is recognized as a conditionally essential amino acid. Recent studies indicate that glutamine-containing total parenteral nutrition improves nitrogen economy, enhances gastrointestinal and immune functions and shortens hospital stay. Methods: Thirty-seven patients (19 w and 18 m; age 61.4±10.4 years; BMI 23.7±2.8 kg/m2) following major abdominal surgery receiving an isonitrogenous isoenergetic TPN with or without alanyl-glutamine supplementation (0.5 g/kg BW/day), were evaluated in a double-blind, randomized, controlled trial over a five-day period by measuring nitrogen balance, selected biochemical parameters and length of hospital stay. Results: Supplemental alanyl-glutamine improved the overall mean (−3.5±1.6 vs. −5.5±1.4 g N;P

Recent advances indicate great potential for new fish oilcontaining lipid emulsions: the possible mechanisms involve suppression of excessive endothelial activity and thereby decreased production of pro-inflammatory mediators. This means that supplemental fish oil (n-3 fatty acids [FA]) may reduce inflammatory and thrombotic responses while protecting tissue microperfusion and immunity. Consequently, supplementation with fish oil might be used to improve standard clinical therapy, especially in chronic hyper-inflammatory diseases and as an adjunct therapeutic measure after trauma, injury, and during early sepsis. Encouraging effects with supplemental fish oil are observed in patients with chronic catabolism associated with cancer cachexia. Suppression of T-cell mediated immune function is an adverse effect with fish oil supplementation. This undesirable effect is partly due to increased lipid peroxidation and decreased antioxidant capacity and can be prevented by appropriate vitamin E supplementation. Parenteral administration of fish oil based emulsions might be advantageous compared to the enteral route because intestinal loss due to lipid remodelling is bypassed. A new type of emulsion made of a physical mixture of soybean-LCT, MCT, olive oil, and fish oil supplemented with vitamin E has been developed. This novel emulsion with reduced content of n-6 FA, high share of MUFAs and increased amount of n-3 FA is composed according to a current NIH recommendation. A randomized double blind clinical trial with the new emulsion revealed rapid incorporatiom of EPA and DHA in cell membranes resulting in a considerably decreased AA/EPA ratio. A profound increase of LTB5 and simultaneous decrease of LTB4 resulted in a marked decrease of the LTB 4/LTB5 ratio. TxB3 increased and TxB2 decreased. These changes are in accordance with the expected biochemical action of fish oil supplementation. We observed a 7 days shorter hospitalization with the new emulsion compared with the standard control LCT emulsion. The results suggest a beneficial immunomodulation probably due to parenteral provision of n-3 FA and olive oil and also because of the considerable reduction of n-6 FA and indicate that it is possible to establish fish oil supplementation protocols that provide maximum beneficial effects while adverse effects are minimized. Future studies need to be focussed on further elucidation of the intra and inter cellular signalling events mediated by n-3 FA. Understanding the molecular mechanism(s) modified by fish oils will ultimately lead to improved dietary strategies to aid the prevention of auto-immune disease, cardiovascular disease, certain type of cancer and to support therapeutical measures of trauma, sepsis and other acute illnesses. There is strong evidence that the future major feature in clinical nutrition in critically ill and chronic illness will be the creation of the optimum lipid emulsion for use in the most beneficial nutrient admixture. The fish oil story ‐ how it started

Short chain peptides -past and present questions Six years ago, in 1984, many of us had the privilege of attending the first ESPEN-AJINOMOTO Research Symposium here in Hotel Atlantic. On that occasion I was asked to introduce the session devoted to a novel topic peptides. I recall the commencement of my presentation: ‘. . . Peptides might be considered as brand new candidates for parenteral nutrition. Their potential use is based on the assumption that ‘tailored’ amino-acid solutions will increase the benefits of intravenous nutrition for specific patient groups. Undoubtedly this new approach has introduced a new dimension, though the explosion of new information about peptide assimilation is only a prelude to intravenous use of peptides in common clinical practice . .’ (1). I closed my lecture with the statement: ‘. . . in the light of the many important unresolved questions, some of which have been emphasised in this presentation, it must be stressed that studies in healthy and diseased man are urgently required before the use of peptides in parenteral nutrition can be established. Thus, it now appears that this novel form of therapy must await increased fundamental knowledge . . .’ (1). Indeed, during the last 6 years, the great interest directed towards peptide research is mirrored by the numerous publications on peptide synthesis and characterisation as well as relative to their in vivo uptake and subsequent utilisation. Considering the present and past problems I suggest three important topics of interest. The first is the availability of suitable peptides. They should be highly soluble and stable during sterilisation procedures. In addition, they must be sufficiently pure to be included in parenteral solutions. The second relates to human studies in healthy volunteers and stressed or malnourished patients. Thirdly, in vivo peptide handling might be of great interest when examining the capacity for and efficacy of utilisation as well as the affinity for hydrolysis of the individual peptides.

Metabolic studies involving changes in plasma substrate concentrations are frequently carried out after an overnight fast. This condition, however, is a transition between the post-prandial period and the beginning of starvation, and thus is associated with rapid changes in the plasma concentration of many substrates. Such alterations might interfere with the interpretation of modifications in plasma concentrations resulting from experimental manipulations. Infusion of glucose at a rate of 250 mg kg(-1) h(-1) for 1h and subsequently at 162 mg kg(-1) h(-1) together with amino-acids at 50 mg kg(-1) h(-1) is used to stabilise the plasma concentration of most substrates within 3 h, a condition which is maintained for the subsequent 5 h or more. This study offers a model which is more suitable for many metabolic investigations than overnight fasting and which takes little time or expense to prepare.