CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O objetivo do presente estudo foi verificar os efeitos da L-alanil-glutamina (Ala-Gln) na isquemia e reperfusÃo em cÃrebro de ratos. Foram utilizados 48 ratos machos, da linhagem Wistar, com idade mÃdia de 62 dias e peso mÃdio de 276,38g, distribuÃdos em quatro grupos: Sham 30 minutos, Isquemia, Sham 90 minutos e Isquemia/ ReperfusÃo. Foi utilizado um modelo de isquemia cerebral experimental global, com oclusÃo da artÃria carÃtida comum bilateral e administraÃÃo de soluÃÃo salina ou Ala-Gln. Os resultados do presente estudo mostraram elevaÃÃo estatisticamente significante no percentual de Ãrea de necrose do grupo Isquemia (13,24  8,82) em relaÃÃo ao grupo Sham 30 minutos (0,12  0,20, p= 0,01). O mesmo ocorreu em relaÃÃo à Ãrea de necrose do grupo Isquemia/ReperfusÃo (13,30  9,91) em relaÃÃo ao Sham 90 minutos (0,70  1,35, p= 0,01). Tais resultados demonstram a efetividade do modelo Isquemia e Isquemia/ReperfusÃo cerebrais utilizados. NÃo foi observada alteraÃÃo significante no percentual de Ãrea de necrose entre os grupos Isquemia Salina (13,24  8,82) e Isquemia Ala-Gln (15,35  6,80, p= 0,34). A mÃdia do percentual de Ãrea isquÃmica do grupo Isquemia/ReperfusÃo Ala-Gln (4,65  1,44) foi significantemente inferior Ãquela encontrada no grupo Isquemia/ReperfusÃo Salina (13,30  9,91, p= 0,03). A administraÃÃo prÃvia de Ala-Gln a ratos submetidos à Isquemia/reperfusÃo cerebral nÃo promoveu reduÃÃo no percentual de Ãrea de necrose na lesÃo isquÃmica. Por outro lado, esse dipeptÃdeo reduziu o percentual de necrose cerebral na lesÃo Isquemia/ReperfusÃo cerebral. / The aim of this study was to investigate the effects of L-alanyl-glutamine (Ala-Gln) in ischemia and reperfusion in rat brain. We used 48 male rats, Wistar, with a mean age of 62 days and average weight of 276.38 g, divided into four groups: Sham 30 minutes ischemia, 90 minutes and Sham Ischemia / Reperfusion. We used a model of experimental global cerebral ischemia with occlusion of bilateral common carotid artery and administration of saline or Ala-Gln. The results of this study showed a statistically significant increase in the percentage of necrotic area of the ischemia group (13.24  8.82) than in group Sham 30 minutes (0.12  0.20, p= 0.01). The same occurred in relation to the area of necrosis in ischemia-reperfusion group (13.30  9.91) compared to Sham 90 minutes (0.70  1.35, p= 0.01). These results demonstrate the effectiveness of the model Ischemia and Ischemia / Reperfusion brain used. There was no significant change in the percentage of necrotic area between Salina ischemia groups (13.24  8.82) and ischemia Ala-Gln (15.35  6.80, p= 0.34). The average percentage of ischemic area of group Ischemia / Reperfusion Ala-Gln (4.65  1.44) was significantly lower than that in group Ischemia / Reperfusion Salina (13.30  9.91, p= 0.03). The prior administration of Ala-Gln in rats subjected to ischemia / reperfusion did not cause reduction in the percentage of necrosis in ischemic injury. Moreover, this dipeptide reduced the percentage of necrosis in the cerebral injury cerebral ischemia / reperfusion.

Nach einem Myokardinfarkt setzen Wundheilungsprozesse ein, um die Durchblutung wieder herzustellen und nekrotisches Muskelgewebe durch Narbengewebe zu ersetzen. Die Einsprossung neuer Kapillaren vom bestehenden Gefäßnetz aus wird als Angiogenese bezeichnet. Das dabei vermehrt exprimierte proteolytische Enzym Aminopeptidase N (APN) spielt eine entscheidende Rolle bei der Einsprossung von Endothelzellen. Beim kardialen Remodeling werden abgestorbene Myozyten mithilfe der Einwanderung von Fibroblasten durch Binde- oder Stützgewebe ersetzt, dabei übernimmt das Fibroblasten-Aktivierungs-Protein alpha (FAP) Aufgaben bei der Proliferation und Fortbewegung von Fibroblasten. Durch ihre erhöhte Expression bei den Wundheilungs- und Remodelingprozessen nach einem Herzinfarkt stellen die Metalloprotease APN und die Serinprotease FAP molekulare Targets für die Diagnostik und Therapie dar. Als Diagnosemethode besonders geeignet ist die Positronen-Emissions-Tomographie (PET), die es ermöglicht, biochemische Prozesse in Echtzeit im zu untersuchenden Organismus zu visualisieren und zu quantifizieren. Eine als Radiopharmakon oder Tracer bezeichnete biochemische Sonde kann im Falle eines Enzyms dessen radioaktiv markiertes Substrat oder ein Inhibitor sein. Ziel dieser Arbeit war es, spezifische APN- und FAP-affine Tracer für die nicht-invasive Untersuchung der APN- und FAP-Expression mittels PET zu entwickeln und dadurch die Rolle von APN und FAP bei Remodelingprozessen nach Myokardinfarkt besser verstehen bzw. klären zu können. Um die Protease APN mittels PET zu untersuchen, wurden die für APN affine Verbindung NOTA-NGR (Komplexbildner + cyclisches Peptid inkl. Asparagin-Glycin-Arginin) mit dem Positronen-emittierenden Nuklid Gallium-68 (68Ga) markiert. Das Potential von 68Ga-NOTA-NGR als PET-Tracer wurde in vivo am Infarktmodell mittels Kleintier-PET untersucht und mit 68Ga-NOTA-RGD, einem zur Visualisierung des neo-angiogenetischen alphavbeta3-Integrins etablierten Tracer, verglichen. Untersuchungen ergaben, dass 68Ga-NOTA-NGR einen vielversprechenden neuen PET-Tracer für die Visualisierung und Quantifizierung der APN-Expression im Rahmen der Angiogenese nach einem Myokardinfarkt darstellt. 68Ga-NOTA-NGR zeigte eine erhöhte Aufnahme im Bereich des Myokardinfarkts im Sinne einer vermehrten Angiogenese. Die Aufnahme des Tracers in infarzierten Arealen war quantitativ höher als in der Untersuchung mit 68Ga-NOTA-RGD. In Autoradiographie-Experimenten wurde 68Ga-NOTA-NGR ex vivo untersucht. Die Akkumulation von 68Ga-NOTA-NGR im ischämischen Bereich war deutlich höher als im gesunden Myokard. Der Nachweis der unterschiedlichen Bereiche des Herzens erfolgte mit HE-Färbung. Die Expression von APN wurde immunohistochemisch mittels spezifischer Antikörper bestätigt. Zum Vergleich wurden ebenso einige andere an der Angiogenese beteiligte Faktoren untersucht. APN stellte sich auch hier als geeignetes Target zum Nachweis der Angiogenese heraus. Um die Protease FAP mittels PET zu untersuchen, wurden eine Reihe peptidomimetischer Inhibitoren, die die Erkennungssequenz Glycin-Prolin mit einer Carbonitril-Gruppe als elektrophiler Einheit zur kovalent-reversiblen Hemmung des Enzyms enthalten, entwickelt. Ausgehend vom N-Acetylglycin-pyrrolidin-(2S)-carbonitril als Leitstruktur wurden Inhibitoren und Vorstufen zur Radiomarkierung inkl. verschieden substituierter Benzoesäuren dargestellt. Zusätzlich wurden noch bereits bekannte Inhibitoren synthetisiert, die zum Vergleich in den Enzymassays dienten. Drei Verbindungen zeigten gute inhibitorische Wirkung an FAP und außerdem Selektivität gegenüber DPP IV. Keine der entwickelten Verbindungen zeigte einen KI-Wert im nanomolaren Bereich, erforderlich für einen potentiellen Tracer zur in-vivo-Visualisierung einer Enzymexpression mittels PET. Um die Inhibitoren mit der besten Hemmung an FAP zum PET-Tracer weiterzuentwickeln, mussten sie mit einem Positronenemitter markiert werden. Die Markierung erfolgte über Isotopenaustausch, bei dem nicht-radioaktives Iod am aromatischen Ring des Precursors durch das radioaktive Iod-124 (124I) substituiert wurde. Es konnten dadurch die radioiodierten Verbindungen 1-(2-[124I]Iodhippursäure)-pyrrolidin-(2S)-carbonitril und 1-(4-[124I]Iod-hippursäure)-pyrrolidin-(2S)-carbonitril synthetisiert werden. Trotz der relativ niedrigen Affinität für FAP wurde das neue 1-(2-[124I]Iodhippursäure)-pyrrolidin-(2S)-carbonitril in Ratten am Infarktmodell mittels Kleintier-PET getestet. Die Lage der ischämischen Zone wurde im Anschluss durch HE-Färbung bestimmt. In vivo zeigte sich eine nur sehr geringe Aufnahme des Radiopharmakons in der ischämischen Zone des Myokards. Damit ist 1-(2-[124I]Iod-hippursäure)-pyrrolidin-(2S)-carbonitril kein für den gewünschten Zweck geeigneter PET-Tracer. Nichtsdestotrotz war der Ansatz vielversprechend und es wurde zum ersten Mal ein PET-Tracer dieser Art zur Untersuchung des FAP im Myokardinfarkt hergestellt. / After myocardial infarction, processes of wound healing are initiated in order to regain perfusion and to replace necrotic muscle tissue with soft tissue. The sprouting of new capillaries from the vasculature is called angiogenesis. During Angiogenesis, Aminopeptidase N (APN) plays an important role in the sprouting of endothelial cells. Cardiac remodeling is the process of replacement of necrotic myocytes with soft tissue through invasion of fibroblasts. For this cause, also a lot of proteases are activated. During the process of cardiac remodeling, fibroblast activation protein alpha (FAP) is involved in proliferation and migration of cardiac fibroblasts. Due to their increased expression during remodeling processes after myocardial infarction, the metalloprotease APN and the serine protease FAP have been identified as potential molecular targets for diagnosis and therapy. Diagnosis of the heart by nuclear imaging techniques is a well established method in clinical cardiology. Most of all positron emission tomopgraphy (PET) provides information on biochemical processes in vivo using specific radiotracers in real time. This imaging probe is labeled with a positron emitting radionuclide and is called radiopharmaceutical or tracer. In case of an enzyme, the tracer might for example be a labeled substrate or inhibitor of the enzyme. To visualize the protease APN with PET, NOTA-NGR (chelating agent + peptide sequence incl. asparagine-glycine-arginine), a compound that shows high affinity for APN, was labeled with the positron emitting nuclide Gallium-68 (68Ga). 68Ga-NOTA-NGR was developed including an improved synthesis, isolation and formulation of the tracer. Its potential as a PET-tracer was assessed in vivo using micro-PET and compared to the established tracer 68Ga-NOTA-RGD, used to visualize the integrin alphavbeta3 in angiogenesis. Studies in rats with ischemia/reperfusion showed high uptake of the new radiopharmaceutical 68Ga-NOTA-NGR in myocardial infarction area being used in diagnostic PET imaging of APN. The new tracer shows even a slightly higher uptake in angiogenetic areas compared with results obtained with 68Ga-NOTA-RGD. 68Ga-NOTA-NGR was also examined ex vivo using autoradiography, confirming the significant higher accumulation of the tracer in the ischemic area compared with the healthy myocardium. The different areas of the tissue were displayed by HE staining. For the purpose of immunohistochemistry, the expression of the enzyme APN was verified using antibody staining. Additionally several other factors that are involved in angiogenesis were stained. Through antibody staining APN was shown to be a suitable target for the evidence of angiogenesis. With 68Ga-NOTA-NGR, the development of a new PET-tracer for diagnosis of the expression of APN during angiogenesis after myocardial infarction was successful. In order to develop an imaging probe suitable for investigation of the protease FAP using PET, several peptidomimetic inhibitors containing the dipeptide motif glycine-proline and the electrophilic moiety carbonitrile were designed. With N-Acetylglycine-pyrrolidine-(2S)-carbonitrile being the basic structure, modifications were introduced through a benzoylic residue at the N-terminus. In addition, some well-known inhibitors were synthesized for comparison to the new ones in enzymatic assay. To evaluate their inhibitory effect, the new inhibitors were tested in enzymatic assays using FAP and dipeptidyl peptidase IV, a prolyl peptidase from the same family in order to compare the results with regard to selectivity. None of the new compounds showed a KI-value in the nanomolar range, required for visualization of an enzyme expression using PET. In order to investigate a PET-Tracer, the best inhibitors against FAP had to be labeled with a positron emitter. The radioactive analogues of the inhibitors were obtained using isotopic exchange of the natural iodine-nuclide by iodine-124 (124I), resulting in 1-(2-[124I]Iodohippuric acid)-pyrrolidine-(2S)-carbonitrile und 1-(4-[124I]Iodohippuric acid)-pyrrolidine-(2S)-carbonitrile. 1-(2-[124I]Iodohippuric acid)-pyrrolidine-(2S)-carbonitrile was tested in vivo using microPET in rats with myocardial infarction. Very low uptake of the radiopharmaceutical was observed in the ischemic area of the rat´s heart. Locations of ischemic and surviving parts of the myocardium were confirmed using HE staining. To our knowledge, 1-(2-[124I]Iodohippuric acid)-pyrrolidine-(2S)-carbonitrile is the first FAP-affine tracer developed for PET investigation. However, its potential as tracer for the FAP-expression within the myocardial infarction in vivo using PET could not be proven in the present study. Therefore, developments based on the structure of 1-(2-[124I]Iodohippuric acid)-pyrrolidine-(2S)-carbonitrile are going on, with view to identify a PET-tracer suitable for in-vivo-investigation of FAP in healing processes and remodeling after myocardial infarction using PET.

Wong Yin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves [110]-126). / Abstracts in English and Chinese. / ABSTRACT --- p.VI / ACKNOWLEDGEMENTS --- p.X / GLOSSARY --- p.XI / Chapter CHAPTER 1 --- INTRODUCTION AND LITERATURE REVIEW --- p.1 / Chapter 1.1 --- Sudden infant death syndrome --- p.1 / Chapter 1.1.1 --- Definition --- p.1 / Chapter 1.1.2 --- Epidemiology of sudden infant death syndrome --- p.1 / Chapter 1.1.3 --- Pathologic findings --- p.5 / Chapter 1.1.4 --- Theories of causation --- p.6 / Chapter 1.1.5 --- Associations of SIDS with temperature and hyperthermia --- p.8 / Chapter 1.1.6 --- Associations of sudden infant death syndrome with infection --- p.11 / Chapter 1.1.7 --- Association of sudden infant death syndrome with sleep state --- p.13 / Chapter 1.2 --- Overview of cytokines --- p.15 / Chapter 1.2.1 --- Definition --- p.15 / Chapter 1.2.2 --- Classification of cytokines --- p.15 / Chapter 1.2.3 --- Biological activities --- p.16 / Chapter 1.2.4 --- Cytokines and temperature --- p.20 / Chapter 1.2.5 --- Cytokines and infection --- p.22 / Chapter 1.2.6 --- Cytokines and smoking --- p.23 / Chapter 1.2.7 --- Cytokines and sleep/arousal --- p.23 / Chapter 1.3 --- Hypothesis and aims of the study --- p.27 / Chapter CHAPTER 2 --- MATERIALS AND METHODS --- p.28 / Chapter 2.1 --- Overview of methods in piglet experiments --- p.28 / Chapter 2.2 --- Pilot study design --- p.30 / Chapter 2.2.1 --- Study Groups --- p.30 / Chapter 2.2.2 --- Temperature controller --- p.33 / Chapter 2.2.3 --- PowerLab system --- p.34 / Chapter 2.2.4 --- Experimental set up --- p.36 / Chapter 2.2.5 --- Provisional ethical approval --- p.36 / Chapter 2.3 --- Problems and results of pilot experiments --- p.37 / Chapter 2.3.1 --- What is baseline body temperature of neonatal rat? --- p.38 / Chapter 2.3.2 --- What type of anaesthesic agent to use? --- p.39 / Chapter 2.3.3 --- What dose of ketamine to use? --- p.40 / Chapter 2.3.4 --- Dilution of ketamine --- p.41 / Chapter 2.3.5 --- Temperature calibration --- p.41 / Chapter 2.3.6 --- What is optimal neonatal rat age to use? --- p.44 / Chapter 2.3.7 --- Which method of blood collection to use? --- p.45 / Chapter 2.3.8 --- What method to raise body temperature? --- p.47 / Chapter 2.3.9 --- Summary results --- p.48 / Chapter 2.4 --- Final study design --- p.49 / Chapter 2.4.1 --- Study animal --- p.49 / Chapter 2.4.2 --- Final Study Groups --- p.50 / Chapter 2.4.3 --- Final ethical approval --- p.56 / Chapter 2.4.4 --- Muramyl dipeptide --- p.56 / Chapter 2.4.5 --- Recalibration of Temperature Controller --- p.57 / Chapter 2.4.6 --- Data collection --- p.58 / Chapter 2.4.7 --- Blood collection and Storage --- p.58 / Chapter 2.4.8 --- Study timetable --- p.59 / Chapter 2.5 --- Cytokines analysis --- p.59 / Chapter 2.5.1. --- Methods of Quantitative Enzyme Immunoassay --- p.59 / Chapter 2.5.2 --- Base theories of Enzyme-linked immunosorbent assay (ELISA) --- p.60 / Chapter 2.5.3 --- Procedure for cytokines assay --- p.61 / Chapter 2.6 --- Histology --- p.65 / Chapter 2.6.1. --- Macroscopic --- p.65 / Chapter 2.6.2. --- Microscopic --- p.65 / Chapter 2.7 --- Data handling and statistical analysis --- p.66 / Chapter CHAPTER 3 --- RESULTS --- p.67 / Chapter 3.1 --- Group (body weight) characteristics --- p.67 / Chapter 3.2 --- Serum concentration of IL- 6，IL-1 β --- p.69 / Chapter 3.3 --- Temperature --- p.78 / Chapter 3.4 --- Mortality rate --- p.80 / Chapter 3.5 --- Cardio-respiratory parameters --- p.85 / Chapter 3.6 --- Macroscopic findings at postmortem --- p.87 / Chapter 3.7 --- Histology --- p.91 / Chapter CHAPTER 4 --- DISCUSSION --- p.96 / Chapter 4.1 --- Study Model --- p.96 / Chapter 4.11 --- Core temperature of newborn rat --- p.95 / Chapter 4.12 --- Temperature calibration --- p.97 / Chapter 4.13 --- Respiratory and pulse rate measurements --- p.93 / Chapter 4.14 --- Measurement of sleep state --- p.99 / Chapter 4.2 --- Animal age and weight --- p.99 / Chapter 4.3 --- Cytokines response to heating --- p.101 / Chapter 4.4 --- Cytokine response to MDP --- p.104 / Chapter 4.5 --- "Hyperthermia, MDP and mortality" --- p.106 / Chapter 4.6 --- Further study --- p.107 / Chapter CHAPTER 5 --- CONCLUSION --- p.109 / Chapter 5.1 --- Small animal model of hyperthermia --- p.109 / Chapter 5.2 --- Hyperthermia and MDP elicit cytokine response --- p.109 / Chapter 5.3 --- Hyperthermia and MDP increase mortality rate --- p.109 / REFERENCES --- p.110 / APPENDICES --- p.A / Appendix 1: Experimental record --- p.A / Appendix 2 : Planned Study Timetable --- p.C / Appendix 3: PowerLab System --- p.E

Oxidative stress has been associated with many disease conditions in adults and neonates based on clinical and post mortem studies. Trauma is the commonest cause of oxidative stress. However a gap in knowledge of the natural history of oxidative stress in humans was identified as most studies have been post mortem or in animals. <p>The aim of this research is to understand treat and oxidative stress in trauma and surgical patients. The study involved three components including: the development and evaluation of the novel oxistress assay; study of clinical trauma and oxidative stress; and clinical trial of alanyl-glutamine supplementation following major surgery. The novel oxistress assay was used on urine samples in the normal population to determine reference values and subsequently on hospital patients to determine sensitivity and specificity. The study of clinical trauma and oxidative stress evaluated plasma antioxidants (FRAP assay), red cell glutathione (Asensis method), plasma and urine protein carbonyl (Levines method) and total oxidants in plasma and urine (oxistress assay) over 7 day period following trauma. The clinical trial was a double blind study of 69 major surgery patients evaluating biochemical and clinical parameters over 7 day period in comparison with pre-operative status. <p>The novel oxistress assay proves to be a sensitive and accurate bedside diagnostic tool for oxidative stress. It can also be used in the laboratory setting. Oxidative stress is associated with increased trauma severity resulting in antioxidant depletion, strong oxidant production and protein degradation. The presence of pre-morbid medical factors also increased oxidative stress in trauma patients. Oral alanyl-glutamine supplementation (0.3 g/kg) increased plasma glutamine and antioxidant levels while decreasing urine oxidant levels. It significantly reduced hospital stay in non-cancer and higher disease complexity patients. The intervention also reduced the resource intensity weighting (RIW) score. <p>Oxidative stress is a clinical problem in surgery and trauma patients that can now be easily diagnosed at the bedside using the novel oxistress assay. Treatment with alanyl-glutamine is effective in reducing oxidative stress and improving clinical outcome. It is highly recommended probably at a higher dose in order to achieve optimal results.

Oxidative stress has been associated with many disease conditions in adults and neonates based on clinical and post mortem studies. Trauma is the commonest cause of oxidative stress. However a gap in knowledge of the natural history of oxidative stress in humans was identified as most studies have been post mortem or in animals. <p>The aim of this research is to understand treat and oxidative stress in trauma and surgical patients. The study involved three components including: the development and evaluation of the novel oxistress assay; study of clinical trauma and oxidative stress; and clinical trial of alanyl-glutamine supplementation following major surgery. The novel oxistress assay was used on urine samples in the normal population to determine reference values and subsequently on hospital patients to determine sensitivity and specificity. The study of clinical trauma and oxidative stress evaluated plasma antioxidants (FRAP assay), red cell glutathione (Asensis method), plasma and urine protein carbonyl (Levines method) and total oxidants in plasma and urine (oxistress assay) over 7 day period following trauma. The clinical trial was a double blind study of 69 major surgery patients evaluating biochemical and clinical parameters over 7 day period in comparison with pre-operative status. <p>The novel oxistress assay proves to be a sensitive and accurate bedside diagnostic tool for oxidative stress. It can also be used in the laboratory setting. Oxidative stress is associated with increased trauma severity resulting in antioxidant depletion, strong oxidant production and protein degradation. The presence of pre-morbid medical factors also increased oxidative stress in trauma patients. Oral alanyl-glutamine supplementation (0.3 g/kg) increased plasma glutamine and antioxidant levels while decreasing urine oxidant levels. It significantly reduced hospital stay in non-cancer and higher disease complexity patients. The intervention also reduced the resource intensity weighting (RIW) score. <p>Oxidative stress is a clinical problem in surgery and trauma patients that can now be easily diagnosed at the bedside using the novel oxistress assay. Treatment with alanyl-glutamine is effective in reducing oxidative stress and improving clinical outcome. It is highly recommended probably at a higher dose in order to achieve optimal results.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / A Escherichia coli enteroagregativa (EAEC) està entre os mais importantes agentes associados Ãs doenÃas diarreicas persistentes (DP) e mostrou-se prevalente em estudos na populaÃÃo infantil em comunidades carentes da cidade de Fortaleza. A EAEC causa lesÃo e inflamaÃÃo intestinal levando a DP e, quando associada à desnutriÃÃo, pode ocasionar um dÃficit cognitivo e reduÃÃo do crescimento infantil. Este estudo analisou in vitro (IEC-6 e HEp-2), o papel da alanil-glutamina (AG) e do betacaroteno nos mecanismos de proliferaÃÃo, apoptose e necrose e em resposta a lesÃo intestinal induzida por uma cepa EAEC selvagem (LDI001), uma cepa controle EAEC 042 e uma cepa de E. coli HS comensal. A cepa LDI001 foi isolada de uma crianÃa desnutrida. Na viabilidade celular houve uma reduÃÃo significativa (p<0.05) pÃs-infecÃÃo com as EAECs nas concentraÃÃes de 105UFC/mL nos tempos de 12, 24 e 48 horas. Contudo, a cepa comensal apenas alterou no tempo tardio (48h). As cÃlulas lesionadas por EAEC diminuÃram a transcriÃÃo (p<0.05) do mRNA dos genes c-jun e c-fos e, apenas tardiamente (12h), com a cepa comensal. A apoptose celular aumentou (p<0.05) apÃs a infecÃÃo com todas as cepas em 24h. PorÃm, o dano persistiu elevado apenas nas cÃlulas tratadas com as cepas de EAEC. A cepa 042 aumentou as cÃlulas necrÃticas (p<0.05) em todos os tempos, embora a LDI001 causou o dano apenas em 24h.Todas as cÃlulas infectadas sofreram aumento da transcriÃÃo (p<0.05) de caspase 8 em 12h. Houve aumento trascricional (p<0.05) de NF-kB em 12h nas cÃlulas infectadas. Enquanto os nÃveis de transcriÃÃo de IL-8 foram altos imediatamente ao termino da infecÃÃo (0h) e houve reduÃÃo em 12h. A LDI001 causou reduÃÃo da viabilidade celular vinculada à sua aÃÃo apoptÃtica. A EAEC 042 induziu danos tanto pela apoptose como a necrose celular. A cepa comensal mostrou um perfil diferenciado das outras cepas provavelmente por nÃo apresentar genes de virulÃncia. A suplementaÃÃo com AG 1mM foi capaz de aumentar a proliferaÃÃo celular (p<0.05) associado a reduÃÃo da apoptose e necrose (p<0.05) nas cÃlulas pÃs-infectadas nos tempos de 12, 24 e 48h. Contudo, a presenÃa de AG 1mM nas cÃlulas infectadas nÃo alterou os baixos nÃveis transcricionais de c-jun e c-fos promovidos pela infecÃÃo, e nÃo conseguiu bloquear a transcriÃÃo significante (p<0.05) de caspase 8. Os nÃveis de transcriÃÃo de NF-kB ainda permaneceu aumentado (p<0.05) na presenÃa de AG em cÃlulas pÃs-infectadas no tempo de 12h. Percebeu-se a continua reduÃÃo temporal da transcriÃÃo de IL-8 nÃo estava associada ao tratamento das cÃlulas infectadas com AG 1mM. A suplementaÃÃo com AG obteve efeitos positivos na proteÃÃo epitelial contra os danos causados pela infecÃÃo das cepas tanto nos processos proliferativos quanto na inibiÃÃo de morte celular. Contudo, a alanil-glutamina nÃo bloqueou a transcriÃÃo de caspase 8 podendo sua funÃÃo antiapoptÃtica estar relacionada a outra via de aÃÃo no presente modelo em estudo. O tratamento com betacaroteno promoveu a reversÃo do dano na viabilidade celular significativa (p<0.05) apenas em 24h apÃs infecÃÃo. Enquanto a presenÃa do betacaroteno em cÃlulas pÃs-infectadas com EAEC selvagem causou aumento de apoptose e necrose (p<0.05) em 48h. CÃlulas infectadas tratadas com betacaroteno nÃo aumentaram os nÃveis de c-jun e c-fos e tambÃm nÃo conseguiram bloquear a transcriÃÃo de caspase 8 e aumentaram (p<0.05) os nÃveis de caspase 3 no tempo de 12h. O betacaroteno mostrou-se potencialmente lesivo Ãs cÃlulas causando morte celular, provavelmente, relacionado aos seus efeitos prooxidantes. / Enteroaggregative Escherichia coli (EAEC) is among the most important agents associated with persistent diarrhea (DP) and was prevalent in studies in children in poor communities in the city of Fortaleza. EAEC cause intestinal injury and inflammation leading to DP and, when combined with malnutrition, can cause a cognitive deficit and infant growth impairment. The current study examined in vitro (IEC-6 and HEp-2) intestinal pathophysiology of three strains: EAEC wild type, EAEC 042 (positive control) and non-pathogenic E.coli HS as well as the role of alanyl-glutamine (AG) and beta-carotene in the mechanisms of proliferation, apoptosis and necrosis in response to the injury caused by EAEC strains. The wild type strain was isolated from a malnourished child. Intestinal cells viability assay in showed a significant reduction (p<0.05) after post-infection with EAEC strains at concentrations of 105UFC/mL in 12, 24 and 48 hours. However, the E.coli HS only changed the intestinal cell viability after 48 hours. EAEC post-infected intestinal cells presented mRNA transcription decrease (p<0.05) of c-jun and c-fos at the period of zero, 6 and 12 hours after infection was terminated, but E.coli HS showed this decrease only after 12h of infection. Intestinal cell apoptosis increased after infection by all strains 24h of infection. However, the cell damage remained intense in the cells treated only with EAEC strains. EAEC 042 increased cell necrosis (p<0.05) in all evaluated periods, but the wild type strain caused damage with only at the period of 24h. All infected cells had a mRNA transcription increase of caspase 8 gene (p<0.05) in12h. NF-kB mRNA transcription increase (p<0.05) was seen in infected cells only in the period of 12h. While transcription levels of IL-8 were extremely high immediately after the infection was interrupted (0h), that was a drastic reduction at 12h after the end of infection. The wild type strain caused a reduction in cell viability linked apoptosis. However, EAEC 042 induced this decrease as also cellular necrosis. E. coli HS showed a different infection profile probably because its lack of virulence genes. AG 1mM supplementation was able to enhance cell proliferation (p<0.05) associated with apoptosis and necrosis reduction (p<0.05) in post-infected cells at the periods of 12, 24 and 48h. However, the presence of AG 1mM in infected cells did not affect the mRNA transcription low levels of c-jun and c-fos as seen after EAEC infection, and failed to block caspase 8 mRNA transcription increase (p<0.05). The IL-8 mRNA transcription temporal reduction was not associated with AG treatment in post-infected cells. Supplementation with AG had positive effects on epithelial protection against damage caused by both EAEC strains in proliferation assay and inhibition of cell death. However, since caspase 8 mRNA transcription decrease was not observed after AG treatment, AG anti-apoptosis feature could be probably related to another mechanism. Beta-carotene cell damage reversal on cell viability assay was statistical significant (p<0.05) 24 hours after infection was ended. Beta-carotene caused 48h apoptosis and necrosis (p<0.05) in wild type strain post-infected cells. Infected cells treated with beta-carotene could not block c-jun and c-fos mRNA transcription reduction and also failed to inhibit caspase 8 mRNA transcription, but beta-carotene itself increased levels of caspase 3 at the period of 12h after infection. Beta-carotene was shown to be potentially harmful to intestinal cells causing cell death probably related to its pro-oxidant effects.

FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / IntroduÃÃo: Apesar do reconhecimento das alteraÃÃes intestinais associadas à desnutriÃÃo e dos efeitos trÃficos da alanil-glutamina (AG) na funÃÃo de barreira intestinal, medida pela taxa de excreÃÃo urinÃria de Lactulose: Manitol, ainda sÃo escassos os estudos para determinar o efeito de suplementaÃÃo oral da AG em crianÃas desnutridas. Objetivos: Examinar o efeito de suplementaÃÃo oral de AG ou placebo glicina (G) na funÃÃo de barreira intestinal e crescimento em crianÃas sob risco nutricional residentes na comunidade do Parque UniversitÃrio do Pici. MÃtodos: Ensaio clÃnico randomizado controlado em crianÃas maiores de 6 meses e menores de 8 anos de idade, com pelo menos um dos escores z para os indicadores antropomÃtricos (IAs) (peso-para-idade, estatura-para-idade e peso-para-estatura) < -1. Cento e sete crianÃas foram randomizadas, entre julho de 2003 a novembro de 2004, para receberem AG (24g/dia) ou G (25g/dia) em quantidades isonitrogÃnicas por 10 dias. A excreÃÃo urinÃria de Lactulose:Manitol foi utilizada como medida da permeabilidade intestinal e realizada nos 1 e 10 dias do protocolo de estudo. O peso e estatura das crianÃas foram coletados nos 1Â, 10Â, 30 e 120 dias do protocolo de estudo para cÃlculo dos IAs. Resultados: O percentual da excreÃÃo urinÃria de lactulose diminuiu significantemente no grupo que recebeu AG, mas nÃo no grupo que recebeu G ( p < 0,05 teste t de Student). A melhora cumulativa nos indicadores antropomÃtricos, peso-para-estatura e peso-para-idade, no 120 dia do protocolo de estudo foi significante quando realizado a anÃlise de covariÃncia no grupo que recebeu AG versus o grupo que recebeu glicina (respectivamente, p <0,04 e <0,029). Durante o perÃodo de estudo foram observados um total de vinte (19%) Eventos Adversos (EAs) na seguinte ordem de freqÃÃncia: vÃmitos (8,4%), diarrÃia (2,8%), nÃuseas (1,9%), infecÃÃo respiratÃria (1,9%), escabiose (1,9%), asma (0,9%), epistaxe (0,9%). Os EAs nÃo foram diferentes na anÃlise estatÃstica entre os grupos estudados e somente trÃs dos EAs foram considerados como SÃrios Eventos Adversos (SEAs ), dois no grupo da alanil-glutamina (1 asma e 1 diarrÃia) e um no grupo da glicina (1 diarrÃia). ConclusÃes: A suplementaÃÃo oral de AG por 10 dias melhorou a permeabilidade intestinal e o estado nutricional em crianÃas sob risco nutricional residentes em uma comunidade de Fortaleza / Introduction: In spite of the recognition of alterations in intestinal barrier function associated with malnutrition and the trophic effects of alanyl-glutamine (AG) on intestinal barrier function, measured by the rate of urinary excretion of Lactulose:Manitol, there are still few studies determining the effect of oral supplementation of AG in malnourished children. Objectives: Examine the effect of oral AG supplementation or the placebo Glycine (G) on intestinal barrier function and growth in children who are at risk for malnutrition and are residents of the University Park of Pici community. Methods: Double blind randomized study in children between 6 months and 8 years of age, with at least one of the z scores for the anthropometrical indicators (AIs) (weight-for-age, height-for-age, and weight-for-height) less than minus one. One hundred and seven children were randomized between July 2003 and November 2004, to receive AG (24 g/day) or G (25 g/day) in iso-nitrogenic quantities for 10 days. The urinary excretion of Lactulose:Mannitol was used as a measure of intestinal permeability, and was performed on the first and tenth days of the study protocol. The weight and height of the children were collected on the 1, 10, 30, and 120 days of the study protocol to calculate the AIs. Results: The percentage of urinary excretion of Lactulose decreased significantly in the group that received AG (p < 0.05 Student T test), but not in the group that received G. The cumulative improvement in the Anthropometrical Indicators, weight-for-height and weight-for-age on the 120 day of the study protocol were significant when covariant analysis was performed in the group which received AG versus the control group G (p < 0.04 and < 0.029, respectively). During the study period a total of 20 (19%) Adverse Events (AEs) were observed in the following order of frequency: vomiting (8.4%), diarrhea (2.8%), nausea (1.9%), respiratory infection (1.9%), scabies (1.9%), asthma (0.9%), epistaxis (0.9%). The AEs were not statistical different between the study groups, and only three of the AEs were considered Serious Adverse Events (SEAs), two in the AG group (1 asthma and 1 diarrhea) and one in the G group (1 diarrhea). Conclusions: The oral supplementation of AG for 10 days improved intestinal permeability and nutritional status in children at risk for malnutrition in a Fortaleza community

Subprojeto 1: Determinação do efeito anti-inflamatório e citoprotetor da suplementação com L-glutamina e L-alanina, ou com L-alanil-L-glutamina (DIP) em ratos submetidos a treinamento resistido. Exercícios intensos reduzem a disponibilidade de glutamina, comprometendo a função imune e a recuperação de atletas. O objetivo do estudo foi avaliar os efeitos da suplementação oral crônica com L-glutamina e L-alanina, nas formas livres ou como dipeptídeo (DIP), sobre parâmetros de lesão, inflamação e citoproteção em ratos Wistar adultos submetidos a treinamento resistido (TR). Neste estudo, o TR reduziu a concentração de glutamina no plasma e no músculo EDL. No entanto, este efeito foi atenuado pelos suplementos contendo L-glutamina, os quais aumentaram os conteúdos da proteína de resposta ao estresse (HSP70) em células do sistema imune (PBMC) e no EDL, concomitantemente à redução da ativação do NF-kB e a da concentração de citocinas no EDL. O efeito protetor das suplementações também foi evidenciado pela atenuação de marcadores de lesão (CK e LDH) e inflamação (TNF-&#945 e IL-1&#946), bem como pelo aumento nas concentrações de marcadores anti-inflamatórios (IL-6, IL-10 e MCP-1) no plasma. Nossos resultados sugerem que a suplementação oral crônica com L-glutamina (administrada com L-alanina livre ou como DIP) promoveu efeitos citoprotetores mediados pela HSP70 em resposta à lesão e inflamação induzidas pelo TR. Subprojeto 2: Efeitos da L-alanil-L-glutamina sobre as vias de sinalização da insulina e da mTOR/S6K, e citoproteção em células musculoesqueléticas C2C12. O dipeptídeo L-alanil-L-glutamina é conhecido por modular o metabolismo e a viabilidade celular. Contudo, os efeitos sobre os componentes clássicos das vias de sinalização da insulina e da mTOR/S6K, bem como o efeito citoprotetor em células musculares, são pouco esclarecidos. O objetivo deste estudo foi investigar o efeito do DIP sobre as vias de sinalização da insulina e da mTOR/S6K em miotubos C2C12, em condições normais ou resistentes à insulina. A exposição crônica à insulina (24h) promoveu resistência à insulina, reduzindo os conteúdos totais do receptor beta (IR-&#946;) e do substrato do receptor de insulina (IRS-1), e diminuindo a fosforilação de IRS-1, AKT e P44/42 MAPK. Adicionalmente, houve redução na expressão do transportador de glicose (GLUT4) e HSP70, redução da viabilidade celular e menor fosforilação de p70S6k e S6, proteínas relacionadas à síntese proteica. Em contraste, a suplementação com DIP aumentou os conteúdos totais de IR-&#946 e IRS-1 e a fosforilação de IRS-1 e AKT. A glicólise anaeróbia e a capacidade glicolítica, além da fosforilação de p70S6k e S6, foram aumentadas pelo DIP em condições normais e na resistência à insulina. Nestas condições experimentais, nossos resultados sugerem que a suplementação com DIP melhorou as vias de sinalizações da insulina e da mTOR/S6K, aumentou a captação e metabolização da glicose, independente da estimulação com insulina e, finalmente, promoveu citoproteção resgatando parcialmente as células de um estado resistente à insulina, por meio do aumento de HSP70 e ativação das etapas finais da via mTOR/S6K. / Subproject 1: Determination of the anti-inflammatory and cytoprotective effects of supplementation with L-glutamine and L-alanine, or with L-alanyl-L-glutamine in rats submitted to resistance training. Intense exercise reduces glutamine availability, compromising immune function and recovery of athletes. The objective of the study was to evaluate the effects of chronic oral supplementation with L-glutamine and L-alanine, in their free form or as dipeptide (DIP), on muscle damage, inflammation and cytoprotection in adult Wistar rats submitted to resistance training (RT). In this study, RT reduced glutamine concentration in plasma and EDL muscle. However, this effect was attenuated by supplements containing L-glutamine, which increased the contents of the stress response protein (HSP70) in immune system cells (PBMC) and EDL, concomitantly with the reduction of NF-kB activation and the concentration of cytokines in EDL. The protective effect of supplementation was also evidenced by attenuation of lesion markers (CK and LDH) and inflammation (TNF-&#945; and IL-1&#946;), as well as by the increase in anti-inflammatory plasma markers (IL-6, IL-10 and MCP-1). Our results suggest that chronic oral supplementation with L-glutamine (administered along with free L-alanine or as DIP) promoted HSP70-mediated cytoprotective effects in response to RT-induced injury and inflammation. Subproject 2: Effects of L-alanyl-L-glutamine on the components of insulin and mTOR/ S6K signaling pathways and cytoprotection in C2C12 musculoskeletal cells. The dipeptide L-alanyl-L-glutamine is known to modulate metabolism and cell viability. However, the effects on the classical components of insulin and mTOR/ S6K signaling pathways, as well as the cytoprotective effect on muscle cells, are poorly understood. The aim of this study was to investigate the effect of DIP on insulin and mTOR/ S6K signaling pathways in C2C12 myotubes, under normal or insulin resistant conditions. Chronic insulin exposure (24h) promoted insulin resistance, reducing the total contents of the insulin receptor (IR-&#946) and the insulin receptor substrate (IRS-1), and decreasing the phosphorylation of IRS-1, AKT and P44/ 42 MAPK. In addition, there was a reduction in the expression of glucose transporter (GLUT4) and HSP70, reduction of cell viability and defective phosphorylation of p70S6k and S6, which are related to protein synthesis. On the other hand, DIP supplementation increased the total contents of IR-&#946 and IRS-1 and the phosphorylation of IRS-1 and AKT. Anaerobic glycolysis and glycolytic capacity, in addition to phosphorylation of p70S6k and S6, were increased by DIP under normal conditions and in insulin resistance. In our experimental conditions, our results suggest that DIP supplementation improved the signaling pathways of insulin and mTOR/ S6K, increased glucose uptake and metabolism, independent of insulin stimulation, and finally promoted cytoprotection by partially rescuing the cells of an insulin resistant state, by increasing HSP70 and activating the final stages of the mTOR/ S6K pathway.

CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / Instituto Dr. Josà Frota / Foram investigados os efeitos metabÃlicos da L-alanil-glutamina nas concentraÃÃes sanguÃneas e teciduais dos metabÃlitos (piruvato, lactato, glicose, acetoacetato, 3-hidroxibutirato, corpos cetÃnicos e ATP) em ratos Wistar submetidos à isquemia/reperfusÃo do membro pÃlvico. Utilizaram-se 96 ratos adultos, machos, distribuÃdos aleatoriamente em 4 grupos numericamente iguais e prÃ-tratados com soluÃÃo salina 2,0 mL (G-1 e G-3) ou L-alanil-glutamina 0,75 g Kg-1(G-2 e G-4), durante 7 dias. Uma hora apÃs a Ãltima gavagem, todos os ratos foram submetidos ao pinÃamento da artÃria ilÃaca esquerda ou operaÃÃo simulada. ApÃs 3 horas a pinÃa foi removida; nos grupos simulados realizou-se nova intervenÃÃo cirÃrgica. Amostras (mÃsculo, fÃgado, rim e sangue) foram coletadas ao final da isquemia mÃxima (T-0) e durante a reperfusÃo (1, 3 e 6h). Os metabÃlitos foram determinados por ensaio enzimÃtico e expressos como MÃdia  E.P.M. Testes nÃo paramÃtricos (Mann-Whitney e Kruskal-Wallis/Dunn) foram utilizados para a anÃlise estatÃstica. O nÃvel de significÃncia foi de p<0,05. NÃo foi evidenciada elevaÃÃo nas concentraÃÃes de lactato, piruvato e glicose durante a lesÃo de isquemia ou reperfusÃo, comparando-se os grupos tratados com soluÃÃo salina (G-1 vs. G-2). Por outro lado houve reduÃÃo nas concentraÃÃes de corpos cetÃnicos em tecido muscular no tempo de isquemia mÃxima e hiperglicemia durante o perÃodo de reperfusÃo. Houve elevaÃÃo nas concentraÃÃes hepÃticas de lactato e glicose muscular e reduÃÃo de lactato no mesmo tecido, nos ratos prÃ-tratados com o dipeptÃdeo. Observou-se ainda, nos mesmos animais, elevaÃÃo das concentraÃÃes de corpos cetÃnicos no fÃgado, no sangue, no mÃsculo e nas concentraÃÃes renais de lactato. Conclui-se, portanto, que o modelo de pinÃamento da artÃria ilÃaca esquerda promove alteraÃÃes metabÃlicas decorrentes da lesÃo de isquemia/reperfusÃo. O dipeptÃdeo L-ALA-GLN induz aumento nas concentraÃÃes hepÃticas de lactato, promove elevaÃÃo de glicose muscular e reduÃÃo de lactato no mesmo tecido indicando aumento no âturn overâ de glicose. O dipeptÃdeo causou aumento da cetogÃnese, cetonemia e captaÃÃo de corpos cetÃnicos durante a reperfusÃo, assim como hiperlactacemia e aumento nas concentraÃÃes renais de lactato. Maior atividade glicolÃtica em tecidos perifÃricos, via ativaÃÃo do ciclo malato-aspartato, levou a diminuiÃÃo da resistÃncia insulÃnica com possÃvel queda de insulinemia, com aumento da cetogÃnese. / A study has been conducted to investigate the effects of L-alanyl-glutamine upon blood and tissue concentrations of metabolites (pyruvate, lactate, glucose, acetoacetato, 3-hydroxybutyrate, ketone bodies and ATP) in Wistar rats subjected to ischemia/reperfusion of hind limb. Ninety-six adult male rats were randomized in 4 groups and pre-treated with saline 2.0 mL (G-1,G-3) or L-alanyl-glutamine solution 0.75 mgKg-1(G-2, G-4) during 7 days. One-hour after the last gavage all rats were submitted to clamping of the left iliac artery or sham operation. The clamp was removed after 3 h; sham rats were operated once more. Muscle, liver, kidney and blood samples were collected at the end of ischemia and at 1-3-6 h during reperfusion. Metabolites were submitted to enzymatic analyses. Results were expressed as Mean  S.E.M. Non-parametric tests (Mann-Whitney and Kruskal-Wallis/Dunn) were utilized for statistical analyses. P<0.05 was accepted as significant. Lactate, pyruvate and glucose concentrations did not increase during ischemia or reperfusion in rats pre-treated with saline (G-1 vs. G-2). On the other hand ketone bodies concentrations were decreased in T-0 and blood glucose was elevated during reperfusion. Liver lactate and muscle glucose were increased and lactate concentration was decreased in L-alanyl-glutamine pre-treated rats. Ketone bodies were elevated in the liver, muscle and blood and renal lactate was also elevated in the aforementioned rats. It is concluded that the model utilized in this study promotes significant metabolic alterations due to ischemia/reperfusion injury. L-Ala-Gln dipeptide induced increased hepatic lactate and muscle glucose concentrations and decreased of muscle lactate concentrations point out to increased turnover of glucose. L-Ala-Gln also induced increased ketogenesis, ketonemia and ketone bodies uptake during reperfusion along with increased lactacidemia and kidney lactate concentrations. Increased glycolytic activity in peripheral tissues via malate-aspartate shuttle activation lead to decreased insulin resistance with possible decrease in plasma insulin levels and increased ketogenesis.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Estudos recentes tem apontado um efeito deletÃrio da hiperglicemia persistente em pacientes submetidos a cirurgia cardÃaca. O controle glicemico estrito abaixo de 110 mg/dl com insulina tem demonstrado exercer um efeito antiinflamatÃrio em pacientes crÃticos,melhorando o prognostico da doenÃa. A glutamina, um aminoÃcido condicionalmente essencial durante o estresse, promove a utilizacao de glicose e aumenta a sensibilidade a insulina em pacientes criticos. Objetivou-se, no presente trabalho, estudar os efeitos de doses nutracÃuticas de L-alanil-glutamina (L-Ala-Gln) administrada no perÃodo prÃ-operatÃrio, associada ao uso intra e pÃs-operatÃrio da infusÃo de insulina. Vinte e dois pacientes adultos (idade media: 63,4 anos), candidatos a cirurgia de revascularizacao do miocÃrdio com circulaÃÃo extracorporea (CEC), foram randomizados em 2 grupos: Grupo salina (GS) e Grupo L-Ala-Gln (GG). Receberam por via endovenosa uma infusÃo de 1.000 ml de soluÃÃo salina (GS) ou 250ml de uma soluÃÃo de L-Ala-Gln a 20% diluÃda em 750 ml de soro fisiolÃgico, nas 3 horas que precederam a intervenÃÃo cirÃrgica. A insulina foi administrada ininterruptamente, durante a realizacao do procedimento cirÃrgico, a ambos os grupos. Amostras de sangue foram coletadas antes e apos a infusÃo da soluÃÃo salina ou da L-Ala-Gln [tempo basal (T-0) e pre-operatorio (T-1) respectivamente]; antes e apos a circulaÃÃo extracorporea (CEC) e no final do perÃodo operatÃrio (T-2); e 12 e 24 horas no perÃodo pÃs-operatÃrio (T3). Foram analisadas as seguintes variÃveis: Insulina, peptÃdeo C, creatinofosfoquinase (CPK), lactato desidrogenase (LDH), ProteÃna C reativa ultra-sensÃvel (PCR), IL-1, IL-6, IL-10, TN-&#61665;, metabolitos (lactato, piruvato, acetoacetato e 3-hidroxibutirato), substancias reativas ao acido tiobarbiturico (TBARS), glutationa reduzida (GSH) e estado antioxidante total (TAS). AtravÃs da punÃÃo digital, amostras de sangue capilar foram coletadas, para analise da glicemia, nos periodos T-0, T-1, a cada hora durante a cirurgia (T-2) e a cada 2 horas apos a cirurgia (T-3). Apesar da administraÃÃo exÃgena de insulina durante a cirurgia ter sido constante em ambos os grupos, nos pacientes do grupo GG, a insulinemia permaneceu em concentraÃÃo semelhante em todos os perÃodos, enquanto que no grupo GS elevou-se em T-2 e T-3 comparado ao valor basal (T-1) (31.9+/-28.8 Versus 6.56+/5.4, p=0.013). O aumento da concentraÃÃo plasmÃtica de glucose foi significativamente menor nos pacientes tratados com L-Ala-Gln no perÃodo intra quando comparado ao grupo controle (129.9+/-15.2 versus 158.6+/-18.6, p= 0.003). NÃo se observaram alteraÃÃes significantes nas concentraÃÃes sericas das demais variÃveis estudadas entre os dois grupos. Conclui-se que a administraÃÃo prÃ-operatÃrio de doses nutraceuticas de L-Ala-Gln em pacientes submetidos a cirurgia cardÃaca com revascularizacao do miocÃrdio com CEC induz uma menor elevaÃÃo da glicemia concomitante a menor elevaÃÃo da insulinemia, o que ressalta o uso potencial da administracao prÃ-operatÃrio desse dipeptideo para atingir um melhor controle glicemico e melhorar a sensibilidade a insulina. / Recent studies have pointed out the negative effects of persistent hyperglycemia in cardiac surgery patients. Tight glucose control below 110 mg/dL with insulin has been shown to exert anti-inflammatory effects in critically ill patients. Glutamine, a conditionally essential amino acid during stress, has been shown to promote glucose utilization and to increase insulin sensitivity in trauma patients. The present study aimed to access the effects of nutraceutical doses of L-alanyl-glutamine preoperatively in a prospective, randomized, controlled, double-blind study. Twenty-two elective patients (63 Â 8 years) with coronary artery disease scheduled for coronary artery bypass grafting were randomly assigned to receive either saline 1000 ml (Group Saline, n=11) or L-alanyl-glutamine 20% (250ml) in saline to final volume 1000 ml (Group L-alanyl-glutamine, n=11). The infusions were started 3 h prior to the operative procedure and lasted 3 hours. Blood samples were collected 3h before [Basal (T-0)], just before the beginning of the surgical procedure [Preoperative (T-1)], at the onset and at the end of the extra-corporeal perfusion (T-2), and at the end of the surgical procedure (Intraoperative). Additional samples were colleted 12 and 24 h later (Postoperative). The following variables were analysed: Insulin, peptide C, creatine phosphokinase (CPK), lactate deshydrogenase (LDH), high sensibility protein C (PCR), IL-1, IL-6, 1L-10, TNF-&#945;, metabolites (lactate, pyruvate, acetoacetate, 3-hidroxibutyrate), reactive substances to thiobarbituric acid (TBARS), reduced glutathione (GSH) and total antioxidant state (TAS). Glucose level were analysed throught capillary blood sample obtained by digital puncture in the periods T-0, T-1, every hour during surgery (T-2) and every two hours after surgery (T-3). Despite the exogenous insulin infusion rate to be constant in both groups during the operation, insulinemia was kept at similar concentrations at all periods studied in patients who received the dipeptide. On the other hand, control patients increased their insulinemia during the intra (T-2) and post-operative period (T-3) as compared to basal values (T-0) (31.9+/-28.8 Versus 6.56+/-5.4, p=0.013). Glucose increasing plasma concentrations were significantly decreased in L-alanyl-glutamine treated patients during the intraoperative period as compared to control patients (129.9+/-15.2 versus 158.6+/-18.6, p= 0.003). No significant difference were observed between the two groups on plasma concentration of others variables studied. In conclusion, the infusion of nutraceutical doses of L-alanyl-glutamine prior to operative period in patients submitted to coronary artery bypass grafting with extracorporeal perfusion, reduce the glicemic surge compared to control patients, without increasing insulin plasma concentrations as compared to their basal values This prospective study highlights the potential use of preoperative L-alanyl-glutamine administration in heart surgery patients to attain glucose control and to improve insulin sensitivity