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O artigo não contém resumo em português. The use of cell and plant tissues culture techniques to produce economically important active metabolites has been growing. Among these substances, azadirachtin (AZA), produced by the neem tree (Azadirachta indica), has received considerable attention due to its bioinsecticide action. The main goal of this work was to analyze the AZA levels in neem cotyledonary calli. The calli were grown in agitated Woody Plant Medium (WPM) liquid medium, supplemented with glucose (Gl), hydrolyzed casein (HC) and methyl jasmonate (MeJ) as elicitor agent. An interaction was observed between these substances, depending on in vitro cultivation time with orbital agitation. The highest concentrations (average of 0.2470 µg g-1) of AZA were produced in the first and second weeks of culture when the cell mass was grown in a medium with 2% Gl v/v, 500 mg L-1 HC and 100 µM of MeJ. This corresponded to approximately 57% of the AZA content stored in the donor plants seeds, used as a source of explants to induce in vitro callus formation. It was concluded that the nutrition, as well as the concentration of MeJ as signal transduction of secondary metabolism in neem cells, might influence the AZA content produced in vitro.

Background It remains controversial whether avoidance of dietary diabetogenic triggers, such as cow's milk proteins, can prevent type 1 diabetes in genetically susceptible individuals. Here, different extensive casein hydrolysates (HC) and single amino acid (AA) formulations were tested for their effect on mechanisms underlying autoimmune diabetes pathogenesis in diabetes-prone BioBreeding rats. Intestinal integrity, gut microbiota composition and mucosal immune reactivity were studies to assess whether these formulations have differential effects in autoimmune diabetes prevention. Methods Diabetes-prone BioBreeding rats received diets in which the protein fraction was exchanged for the different hydrolysates or AA compositions, starting from weaning until the end of the experiment (d150). Diabetes development was monitored, and faecal and ileal samples were collected. Gut microbiota composition and cytokine/tight junction mRNA expression were measured by quantitative polymerase chain reaction. Cytokine levels of ileum explant cultures were measured by ELISA, and intestinal permeability was measured in vivo by lactulose-mannitol assay. Results Both HC-diet fed groups revealed remarkable reduction of diabetes incidence with the most pronounced effect in Nutramigen (R)-fed animals. Interestingly, AA-fed rats only showed delayed autoimmune diabetes development. Furthermore, both HC-fed groups had improved intestinal barrier function when compared with control chow or AA-fed animals. Interestingly, higher IL-10 levels were measured in ileum tissue explants from Nutramigen (R)-fed rats. Beneficial gut microbiota changes (increased Lactobacilli and reduced Bacteroides spp. levels) were found associated especially with HC-diet interventions. Conclusions Casein hydrolysates were found superior to AA-mix in autoimmune diabetes prevention. This suggests the presence of specific peptides that beneficially affect mechanisms that may play a critical role in autoimmune diabetes pathogenesis. Copyright (c) 2012 John Wiley & Sons, Ltd.

Aims/hypothesis The Trial to Reduce IDDM in the Genetically at Risk (TRIGR) study was designed to establish whether weaning to a highly hydrolysed formula in infancy subsequently reduces the risk of type 1 diabetes. Methods The study population comprises newborn infants who have first-degree relatives with type 1 diabetes and meet the increased risk HLA inclusion, but not exclusion criteria. The study is being performed in 15 countries in three continents. First-degree relatives of patients with type 1 diabetes were identified from diabetes clinics, diabetes registries, and from other endocrinology or obstetrics offices and websites. HLA typing was performed at birth from cord or heel stick blood, and the results sent to the study’s Data Management Unit within 2 weeks for communication of eligibility to the clinical study centre. All mothers recruited were encouraged to breastfeed. The intervention lasted for 6 to 8 months, and weaning formulas based on hydrolysed casein and standard cow’s milk were compared. Results TRIGR recruited 5,606 infants, of whom 2,160 were enrolled as eligible participants, 6% more than the target of 2,032. Of those enrolled, 80% were exposed to the study formula. The overall retention rate over the first 5 years is 87%, with protocol compliance at 94%. The randomisation code will be opened when the last recruited child turns 10 years of age, i.e. in 2017. Conclusions/interpretation The TRIGR experience demonstrates the feasibility and successful implementation of an international dietary intervention study. TRIGR is the first ever primary prevention trial for type 1 diabetes and, if completed successfully, will provide a definite answer to the research question. Trial registration ClinicalTrials.gov NCT00179777 Funding The study was funded by the National Institute of Child Health and Development (NICHD) and National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), National Institutes of Health (NIH) (grant numbers HD040364, HD042444 and HD051997), Canadian Institutes of Health Research, the Juvenile Diabetes Research Foundation International and the Commission of the European Communities (specific RTD programme ‘Quality of Life and Management of Living Resources’, contract number QLK1-2002-00372 ‘Diabetes Prevention’. Other funding came from the EFSD/JDRF/Novo Nordisk Focused Research Grant, Academy of Finland, Dutch Diabetes Research Foundation and Finnish Diabetes Research Foundation). Electronic supplementary material The online version of this article (doi:10.1007/s00125-010-1964-9) includes details of the TRIGR Writing Group, plus a complete list of investigators and other TRIGR staff members, and is available to authorised users.

The characterization and measurement of endogenous ileal nitrogen and amino acid excretion of simple-stomached animals, including pigs and poultry, is important to an understanding of gastro-intestinal physiology, as having practical application in the determination of amino acid requirements by the factorial method and the determination of dietary true amino acid digestibility. Studies indicate that the amount of endogenous nitrogen entering the mammalian gastro-intestinal tract is considerable. Traditionally, the net endogenous loss of protein from the ileum has been determined by feeding animals a protein-free diet, although the regression technique has been applied also. However, the protein-free method may lead to considerable underestimation of the physiologically normal level of endogenous excretion. The regression technique seems to give rise to endogenous loss values similar to those obtained after feeding animals to a protein-free diet and therefore the use of this approach may also lead to error. Moreover, the homarginine (guanidination) method in which intact protein is given to the animal, allows direct measurement only for the endogenous loss of lysine. An alternative and more general approach is the isotope (either a radioactively labelled amino acid or the stable isotobe;15N) dilution method. Central to this method is choice of a suitable precursor pool for the endogenous nitrogen-containing material. However, because the nature and origin of these nitrogen-containing compounds is not fully resolved, it is not possible to specify a precursor pool with confidence. A new method for determining endogenous ileal amino acid excretion that involves feeding the animal peptides followed by ultrafiltration of the ileal digesta, has been proposed and evaluated. The enzyme hydrolysed protein approach is not subject to the criticisms of the protein-free or regression methods. Given the unphysiological nature of protein-free dietary state and the problems associated with the other methods, the enzyme hydrolysed protein method may give rise to more meaningful estimates of basal endogenous nitrogen and amino acid tools.

Previous investigations showed that Schistosoma mansoni infection aggravates protein malabsorption in undernourished mice and this can be reverted by administration of casein hydrolysate. The present study was undertaken to evaluate the effects of ingestion of casein hydrolysate for long periods. Albino Swiss mice were divided into eight groups. Diets contained 5% (undernourished ) or 20% (controls) casein levels. For each group there were sub-groups ingesting whole or hydrolysed casein for 12 weeks. Infection with S. mansoni developed in half of the animals under each diet. All undernourished mice developed malabsorption. Low albuminemia was detected in infected animals independently of the protein level in the diet. However, albuminemia was lower in infected controls than in undernourished non-infected mice, suggesting a deficient liver protein synthesis. Infected mice fed on a 20% protein hydrolysed diet exhibited low weight gain and high mortality rates. On the other hand, non-infected mice ingesting the same diet had the highest body weights. We are investigating the hypothesis that infected mice, even when fed normal diets, are unable to metabolise large amounts of amino acids due to the liver lesions related to schistosomiasis and as a result die of hepatic coma. In some of them, the excessive accumulation of ammonia in the blood enhances the outcome of an encephalopathy.