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The occurrence of inflammation and protein malnutrition is an aggravating risk factor for morbidity and mortality in the clinical setting. The green propolis, a natural product made by Apis mellifera bees from Baccharis dracunculifolia resin, has therapeutic potential to modulate chronic inflammation. However, its effect on inflammation in an impaired nutritional status is not known. The aim of this study was to characterize the effects of the administration of the hydroalcoholic extract of the green propolis in the chronic inflammatory process of mice submitted to a low-protein diet. For this, we used the subcutaneous implantation of sponge disks as an inflammatory model and the animals were distributed in the following groups: standard protein diet (12% protein content), control treatment; standard protein diet, propolis treatment; low-protein diet (3% protein content), control treatment; low-protein diet, propolis treatment. Propolis was given daily at a dose of 500 mg/kg (p.o.) during a period of 7 or 15 days. Our main findings show that animals fed with standard protein diet and treated with propolis had low levels of red blood cells, hemoglobin, and hematocrit, with the subsequent reestablishment of these levels, in addition to monocyte count elevation and higher TNF levels after one week of treatment. In the low-protein diet group, the propolis treatment provided a significant recovery in weight and maintenance of total serum protein levels at the end of two weeks of treatment. Histological analysis showed propolis reduced the inflammatory infiltrate in the sponges of both standard and low-protein diet groups. In addition, the propolis extract presented antiangiogenic effect in both groups. Therefore, our data suggests that the hydroalcoholic extract of the green propolis promotes weight recovery and avoid the reduction of protein levels, in addition to inhibit inflammation and angiogenesis in animals fed with a low-protein diet.

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A desnutrição proteica continua sendo um dos principais problemas nutricionais do mundo. Trabalhos de nosso laboratório e de outros autores evidenciam que entre as alterações presentes na desnutrição proteica, está a alteração do tecido hemopoético, com modificações em componentes da matriz extracelular, alterações no ciclo celular da célula tronco/progenitora hemopoética, redução da produção de precursores hemopoéticos, tanto na série eritrocitária como na série leucocitária, levando a anemia e leucopenia. Os mecanismos de participação do Ca2+ nas células da medula óssea são pouco conhecidos, porém, sabe-se que ele atua no processo de hemopoese. Têm sido descrito que elevações da concentração de Ca2+ citoplasmático induzem a proliferação e diferenciação de células mielóides. A ação dessa via em indivíduos desnutridos também é pouco conhecida. Este estudo tem como objetivo avaliar o estabelecimento da celularidade medular in vitro, bem como investigar mecanismos moleculares envolvidos na proliferação e diferenciação dessa celularidade, além de avaliar a ação do cálcio na presença da interleucina-3 em células-tronco hemopoéticas murinas e sua modulação para avaliar alterações na via das MAPKs. Camundongos C57BL/6, machos e adultos foram submetidos à desnutrição proteica e, após a perda de aproximadamente 20% de seu peso corporal, as células da medula óssea foram colhidas. Essas células foram imunofenotipadas, além de reagirem com anticorpos específicos para caracterização da célula-tronco hemopoética e proteínas da via de sinalização de cálcio intracelular. Observamos que a celularidade do estroma medular em cultura de longa duração de animais desnutridos é alterada, principalmente em células de origem mesenquimal, que aparecem em maior número em desnutridos ao longo dos dias de cultura. Além disso, as ondas de cálcio intracelular estavam diminuídas em animais desnutridos, bem como as proteínas p-PKC, p-PLCy, CAMKII, p-AKT e p-STAT5 não respondem ao estímulo de IL-3, levando a uma deficiência da expressão das MAPK: ERK 1/2, JNK e p38. A desnutrição proteica pode causar alterações na celularidade estromal da medula óssea e na diferenciação das células tronco hemopoéticas pela via das MAPKs estimulada por IL-3

Protein malnutrition remains one of the world's major nutritional problems. Studies from our laboratory and others shown that alterations in protein malnutrition include hemopoietic tissue alterations, changes in extracellular matrix components, changes in the hemopoietic stem/progenitor cell tissue, reduction in the production of hemopoietic precursors, in the erythroid series as in the mieloyd series, leading to anemia and leukopenia. Mechanisms of Ca2+ participation in bone marrow cells are poorly understood, but no hemopoiesis has been developed. Elevations of cytoplasmic Ca2+ concentration in proliferation and differentiation of myeloid cells were included. Such an action through malnourished animals is also a little known. This study aims to evaluate the establishment of cellularity in vitro as well as investigate the molecular involvement in cell proliferation and differentiation, as well as to evaluate the action of calcium in the presence of IL-3 in hemopoietic stem cells and its modulation by analytical evaluations in the MAPKs pathway. C57BL/6, male adult mices were subjected to protein restriction and, after loss of approximately 20% of their body weight, bone marrow cells were harvested. These were immunophenotyped in addition to specific activation terms for the hemopoietic stem cell and intracellular signaling pathway proteins. We observed that the bone marrow cells in long-term culture of malnourished animals is altered, mainly in cells of mesenchymal origin, which appears in greater numbers in undernourished throughout the days of culture. In addition, as intracellular calcium waves decreased in malnourished animals, as well as the p-PKC, p-PLC, CAMKII, p-AKT and p-STAT5 proteins did not respond to IL-3, sugesting expression of the expression of MAPK: ERK 1/2, JNK and p38. Protein malnutrition may have changes in bone marrow capacity and differentiation of hemopoietic stem cells through IL-3-stimulated MAPKs

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OBJETIVO: Investigou-se os efeitos do tratamento com triptofano sobre o consumo alimentar em ratos adultos, submetidos ou não a desnutrição precoce. MÉTODOS: Sessenta e quatro ratos Wistar machos foram divididos em nutridos (n=32, caseína=17 por cento) e desnutridos (n=32, caseína=8 por cento), de acordo com a dieta materna empregada no período de lactação. Após o desmame, todos os ratos receberam dieta com 23 por cento de proteína. Pesos corporais foram avaliados no sétimo, vigésimo primeiro e septuagésimo dias de vida. Aos setenta dias de idade, cada grupo nutricional foi dividido em subgrupos: Nutrido-Salina (n=16) e Nutrido-Triptofano (n=16), Desnutrido-Salina (n=16) e Desnutrido-Triptofano (n=16). Os grupos receberam diariamente 1,0mL/100g de triptofano, na dose de 50mg/kgP ou salina (0,9 por centoNaCl), durante 14 dias. Neste período foram realizados os estudos dos parâmetros do comportamento alimentar. Posteriormente obteve-se a média do consumo alimentar relativo e a média do ganho de peso relativo. As análises estatísticas foram feitas utilizando os testes t Student e ANOVA seguido de Tukey, com p<0,05. RESULTADOS: As ninhadas de mães alimentadas com dieta hipoproteica mantiveram pesos inferiores comparados com as ninhadas nutridas (p<0,01) até os setenta dias de vida. Os ratos nutridos tratados com triptofano (M=6,88, DP=0,05) reduziram a ingestão alimentar comparados aos nutridos salina (M=7,27, DP=0,08) (p<0,01). Contudo, não houve efeito sobre o ganho de peso. Entre os desnutridos nenhuma diferença foi encontrada. CONCLUSÃO: Nesse estudo, a restrição proteica neonatal alterou a evolução ponderal em ratos. Além disso, a desnutrição precoce tornou os ratos adultos resistentes aos efeitos inibitórios do triptofano sobre a ingestão alimentar.

OBJECTIVE: This study investigated the effects of tryptophan on the eating behavior of adult rats submitted or not to early malnutrition. METHODS: Sixty-four male Wistar rats were divided into nourished (n=32, casein=17 percent) and malnourished (n=32, casein=8 percent) according to the diet given to the dam during lactation. After weaning, all rats were fed a diet with a protein content of 23 percent. The rats were weighed on day 7, day 21 and day 70 after birth. On day 70 after birth, each nutritional group was divided into 4 subgroups: nourished-saline (n=16), nourished-tryptophan (n=16), malnourished-saline (n=16) and malnourished-tryptophan (n=16). The tryptophan groups were given 1.0mL/100g of tryptophan for 14 days, at a dosage of 50mg/kgw of body weight and the saline groups were given 1.0mL/100g of 0.9 percent NaCl, also for 14 days. The eating behavior parameters were assessed during this period. The mean relative food intake and mean relative weight gain were then determined. The statistical analyses were done by the Student's t-test and ANOVA, followed by the Tukey test, with p<0.05. RESULTS: During the first 70 days of life, pups from protein-malnourished damns remained lighter than pups from well-nourished damns (p<0.01). Well-nourished rats treated with tryptophan (M=6.88, SD=0.05) ate less than those given saline (M=7.27, SD=0.08) (p<0.01) but weight was unaffected. No difference was found for the malnourished rats. CONCLUSION: In this study, neonatal protein restriction affected weight gain in rats. Furthermore, early malnutrition made adult rats resistant to the inhibitory effects of tryptophan on food intake.

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OBJETIVO: Foram avaliados os efeitos do condicionamento físico aeróbio moderado sobre o peso corporal e o ganho de peso de animais submetidos à desnutrição na gestação e lactação e alimentados com dieta normoprotéica após o desmame. MÉTODOS: Ratos machos Wistar foram gerados e amamentados por nutrizes alimentadas com dieta normoprotéica (caseína 17 por cento) e dieta hipoprotéica (caseína 8 por cento), formando os grupos Nutridos (n=18) e Desnutridos (n=17) inicialmente e, após o desmame, foram alimentados com dieta normoprotéica padrão do biotério (Labina®, Purina). Aos 60 dias de vida, os animais foram subdivididos em quatro grupos: Nutrido Sedentário (n=9), Nutrido Condicionado (n=7), Desnutrido na Gestação e Lactação Sedentário (n=8) e Desnutrido na Gestação e Lactação Condicionado (n=9). O condicionamento físico aeróbio moderado foi realizado em esteira elétrica durante 8 semanas, 5 dias/ semana, 60min/dia e os animais sofreram eutanásia após o término do protocolo. Realizaram-se as análises do peso corporal (g) e do ganho de peso corporal ( por cento). RESULTADOS: Observou-se menor peso corporal nos grupos Desnutrido na Gestação e Lactação Sedentário (247,00: 134,00 - 335,00) e Desnutrido na Gestação e Lactação Condicionado (245,00: 166,00 - 324,50) comparados respectivamente, aos grupos Nutrido Sedentário (303,75: 176,00 - 372,00) e Nutrido Condicionado (290,25: 190,00 - 372,00) (p<0,05). O ganho de peso mostrou-se maior nos animais do grupo Desnutrido na Gestação e Lactação Sedentário (35,40: -6,20 - 77,10) comparado ao Nutrido Sedentário (24,30: -7,50 - 44,30) (p<0,05) e comparado ao Desnutrido na Gestação e Lactação Condicionado (20,50: -2,30 - 59,00) (p<0,05). CONCLUSÃO: O condicionamento físico aeróbio moderado exerceu um efeito benéfico por ter reduzido o rápido ganho de peso (catch up) dos animais adultos desnutridos na gestação e lactação e alimentados com dieta normoprotéica após o desmame.

OBJECTIVE: The objective of this study was to assess the effects of moderate aerobic physical conditioning on the body weight and weight gain of rats whose mothers were fed a low protein diet during gestation and lactation. METHODS: Male Wistar rats were bred from dams fed a normal- (17 percent casein) or low-protein (8 percent casein) diet, constituting the initial nourished (n=18) and malnourished (n=17) groups. After weaning, they were fed the standard diet of the laboratory, with normal protein content (Labina®, Purina). At the age of 60 days, the animals were divided into four groups: inactive and well nourished (n=9), active and well nourished (n=7), inactive and malnourished from conception until weaning (n=8) and active and malnourished from conception until weaning (n=9). Moderate aerobic physical conditioning was done on a treadmill for 8 weeks, 5 days per week, 60 minutes per day. All animals were killed after this training period. Body weight (g) and weight gain ( percent) were analyzed. RESULTS: Lower body weights were seen in animals that were inactive and malnourished from conception until weaning (247.00: 134.00 - 335.00) and active and malnourished from conception until weaning (245.00: 166.00 - 324.50) when compared with the animals that were inactive and well nourished (303.75: 176.00 - 372.00) and active and well nourished (290.25: 190.00 - 372.00) (p<0.05). Weight gain was higher in the animals from the inactive and malnourished group (35.40: -6.20 - 77.10) in comparison with the inactive and well nourished group (24.30: -7.50 - 44.30) (p<0.05) and the active and malnourished group (20.50: 2.30 - 59.00) (p<0.05). CONCLUSION: Moderate aerobic physical conditioning had a beneficial effect on the animals that were malnourished during their mothers' gestation and lactation as it reduced their rapid weight gain.

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OBJETIVO: Avaliar se a desnutrição protéica imposta no início da vida produz prejuízos em um procedimento experimental de memória social em ratos (Rattus norvegicus). MÉTODOS: Os animais receberam dietas isocalóricas contendo 6 por cento ou 16 por cento de proteína do nascimento aos 21 dias, e dieta comercial a partir de 22 dias de idade. O teste de memória social consistiu em, após duas sessões de habituação (7 minutos/sessão), introduzir um animal adulto (100-114 dias de idade) e um outro jovem (30-44 dias de idade) em uma arena de acrílico (90cm x 90cm x 45cm) em duas sessões separadas por intervalos de 30 (experimento 1) ou 15 minutos (experimento 2). O contato social foi definido como investigação (ato de cheirar/inspecionar a região anogenital). A diferença no tempo de contato entre a primeira e a segunda exposição é considerada um índice de memória social. RESULTADOS: Nenhuma diferença devida à dieta foi observada no experimento 1. No experimento 2 houve redução no tempo de contato social dos animais-controle da primeira para a segunda exposição (p<0,05) e não houve alteração nos animais desnutridos. CONCLUSÃO: Esses resultados sugerem que a desnutrição protéica precoce prejudica a memória social de ratos adultos.

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OBJETIVO: O objetivo do presente estudo foi verificar a concentração de trombospondina da matriz extracelular da medula óssea em camundongos após indução de hipoplasia por desnutrição protéica. MÉTODOS: Camundongos machos Swiss foram submetidos à desnutrição protéica com uma dieta contendo 4,0% de caseína até que perdessem 20,0% do peso original, enquanto o grupo-controle foi mantido com uma dieta contendo 14,0% de caseína por 15 dias. A medula óssea dos dois grupos foi então aspirada e extraída com tampão fosfato. A matriz extracelular foi analisada por SDS-PAGE 7,5% e a concentração de trombospondina foi quantificada por Enhanced Chemiluminescence Light Western blotting, com luminescência química avançada. RESULTADOS: A quantidade de trombospondina foi 30% superior nas amostras obtidas de animais desnutridos em relação às amostras do grupo-controle. CONCLUSÃO: Este estudo sugere que a concentração de trombospondina está aumentada na hipoplasia induzida por desnutrição protéica, provavelmente por alterar o microambiente da medula óssea.

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To determine the effect of low protein and cornbased diets on the maturation of cerebellum, three groups of young rats were fed during a period of 6 weeks with different diets; 23 and 8 percent of protein (purina-Chow base) and a corn-based diest (8 percent protein). At the end of that period, the concentrations of free amino acids in the cerebellum was measured. Glutamic acid, glucine, glutamine and serine showed the highest values in all groups studied. Corn-based diet group showed the lowest free amino acid concentration compared to that of the control group, with a significant diminutions in the concentration of glutamic acid, lysine, tyrosine and histidine. Differences between essential and nonessential amino acids were not observed in all groups studied. Although corn-based diet did not induce specific changes as those reported in severe malnutrition, its effects on the concentration of some amino acids other than tryptophan could have some physiological correlations which need to be further studied

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The aim of this work was to make an assessment of the role of impaired lipoprotein secretion from the liver in the pathogenesis of the fatty liver caused by protein malnutrition in infants. The only evidence for this role prior to the study was that serum lipid levels were lower than normal in patients with fatty liver. The proposed method for measuring the incorporation of amino acids into the lipoproteins of children with fatty liver was used first with the rat as a model. It was found, in the development of such a model, that there are great variations in the level of liver fat induced by protein depletion in the rat. The variations depend on the age and nutritional state of the animal at the time of introducing the low-protein diet, and depend on the calorie intake while thay are on the diet. It was found that there were always measurable increases in the liver fat content when 70-gram rats were fed a 6 percent casein diet for 7 to 10 days. The use of this model with either single-injection or constant-infusion techniques showed that the incorporation of labelled amino acids into the serum lipoproteins was reduced. The greatest reduction was in the VLDL fraction of the low-density lipoproteins. There was no evidence for any significant contribution to the fatty liver from increased lipogenesis at the time when the defect in lipoprotein synthesis was apparent. The incorporation of methionine-S35 into the low-density lipoproteins of malnourished children was measured; although the changes were not consistent throughout the group studied, there was some evidence that the incorporation of the amino acid into lipoproteins was less when the children were malnourished than when they had recovered. Some modification in the design of future experiments of this type are discussed. Routine measurements of serum triglycerides in the patients during treatment showed that there are some differences between the pattern seen here and that reported elsewhere. The patients had very low triglyceride levels after recovery. These low levels were found to be due to the high fat content of the diet which the patients received during treatment. The changes in serum triglycerides induced by changing the fat content of the diet were found to be more rapid and to be relatively greater than any changes previously reported for adults. No explanation for this is given at present. The unusual patterns for serum triglycerides found during treatment of the malnourished patients with a low-fat diet appeared at first to be inconsistent with reduced synthesis of lipoprotein being associated with the fatty liver; other changes in fat metabolism concurrent with such a defect, however, could account for the unusual patterns.(AU)

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