Pacientes com doença renal crônica (DRC) na fase não dialítica são normalmente orientados a seguir uma dieta hipoproteica e hipossódica. Estudos nacionais e internacionais mostram que a adesão a essa dieta tem sido baixa e difícil de ser mantida, pois requer mudanças importantes no hábito alimentar. O objetivo do presente estudo foi avaliar o impacto de um programa de educação nutricional sobre a adesão à dieta hipoproteica em pacientes com DRC em tratamento conservador. Trata-se de um ensaio clínico randomizado, prospectivo com duração de 5 1,5 meses. Foram acompanhados 85 pacientes com DRC na fase não dialítica, atendidos em dois Ambulatórios de Nutrição e Doenças Renais do Hospital Universitário Pedro Ernesto. Os pacientes foram divididos de forma aleatória em 2 grupos: Intervenção (n=39) e Controle (n=46). Os pacientes do Grupo Intervenção foram submetidos a um programa de educação nutricional, além da orientação de dieta hipoproteica (0,6 a 0,75 g/kg/dia). Os pacientes do Grupo Controle foram submetidos apenas à orientação de dieta hipoproteica (0,6 a 0,75 g/kg/dia). A avaliação da adesão foi feita a partir da estimativa do consumo de proteína por recordatório alimentar de 24 horas. Adotou-se como critério de adesão apresentar ao final do estudo redução de ao menos 20% da ingestão proteica inicial. A avaliação nutricional e laboratorial foi realizada no início e no término do estudo. Os parâmetros antropométricos avaliados foram peso, estatura, dobras cutâneas do tríceps, bíceps, subescapular e supra-ilíaca e perímetro da cintura e do braço. As laboratoriais foram creatinina, uréia, potássio, fósforo, glicose e albumina no plasma e sódio e uréia na urina de 24 horas. Ao avaliar o amostra total, 51,8% dos pacientes eram do sexo masculino, com média de idade de 63,4 11,0 anos, IMC indicativo de sobrepeso (28,8 5,4 kg/m2) e filtração glomerular estimada (FGe) de 32,6 12,2 mL/mim/1,73m2. As características iniciais não diferiram entre os Grupos Intervenção e Controle. Ambos os grupos apresentaram melhora dos parâmetros laboratoriais e antropometricos, com redução significante da uréia plasmática e da glicemia no Grupo Controle (P < 0,05 vs início do estudo) e do IMC em ambos os grupos (P < 0,05 vs início do estudo). Após o período de acompanhamento, o Grupo Intervenção e o Grupo Controle apresentaram ingestão proteica significantemente diferente (0,62 0,2 vs 0,77 0,26 g/kg/dia, respectivamente). A ingestão de sódio não mudou de forma significante em ambos os grupos no inicio e término do acompanhamento. A Adesão à ingestão proteica foi observada em 74,4% do Grupo Intervenção e em 47,8% do Grupo Controle (P < 0,05). A análise de regressão logística multivariada revelou que pertencer ao Grupo Intervenção e sexo masculino se associaram com a Adesão (P <0,05), mesmo após corrigir para outras variáveis testadas. Com base nos achados desse estudo, pode-se concluir que o programa de educação nutricional foi uma ferramenta eficaz no tratamento dietoterápico do paciente com DRC na pré-diálise, pois promoveu melhora na adesão à dieta hipoproteica, além de ter promovido melhora dos parâmetros antropométricos e laboratoriais. / Nondialyzed chronic kidney disease (CKD) patients are normally counseled to follow a low protein and sodium diet. Nationals and internationals surveys have shown a low adherence to such diet. In addition, it has been also demonstrated that maintaining a low protein and sodium intake is difficult, because it requires important changes in eating habits. The objective of the present study was to evaluate the impact of a nutritional education program on the adherence to the low protein diet in CKD patients being followed in a conservative outpatient clinic. Study design: clinical, randomized, controlled and prospective essay (follow-up of 5 1.5 months (mean SD)). Eighty five nondialyzed CKD patients, under treatment in two CKD outpatient clinics from Pedro Ernesto University Hospital, were included in this study. These patients were randomized in two groups: Intervention (n=39) and Control (n=46). The patients of the Intervention Group were submitted to a nutritional education program, besides the low protein diet prescription (0.6 to 0.75 g/kg/day). The patients from the Control Group were submitted only to the low protein diet prescription (0.6 to 0.75 g/kg/day). The evaluation of the adherence was done by estimating the protein intake from the 24 hour food recall. The adherence criterion adopted was to present, at the end of the study, a reduction of at least 20% of the initial protein intake. The nutritional and laboratorial assessments were made at the beginning and at the end of the follow-up period. The anthropometric parameters assessed were body weight, height, triceps, biceps, subscapulars and suprailiacs skinfolds thicknesses and waists and arms circumferences. The laboratorial parameters included plasma creatinine, urea, potassium, phosphate, glucose and albumin and 24 hour urines sodium and urea. In the total studied sample, 51.8% of the patients were male, with an mean age of 63.4 11.0 years, mean BMI indicating overweight (28.8 5.4 kg/m) and a mean glomerular filtration rate (GFR) of 32.6 12.2 mL/mim/1,73m. The main characteristics at the beginning of the follow-up were not different between Intervention and Control Groups. Both groups presented an improvement on the laboratorial and anthropometrical parameters, with significant reduction of plasma urea and glucose in the Control Group (P < 0.05 vs baseline) and BMI in both groups (P < 0.05 vs baseline). After the follow-up period, the Intervention and Control Groups showed a significant decrease in the protein intake (0.62 0.2 vs 0.77 0.26 g/kg/day, respectively). The sodium intake did not significantly change in both groups at the beginning and end of the study. A higher degree of adherence to the low protein diet was observed in Intervention Group (74.4%) than in Control Group (47.8%) (P < 0.05). The multivariate logistic regression analysis revealed that belonging to the Intervention Group and male gender were significantly associated with Adherence (P < 0.05), even after controlling to others tested variables. Based on these findings, it can be concluded that the nutritional education program was an effective tool to reduce the protein intake of nondialyzed CKD patients, as it has leaded to an improvement in the adherence to the low protein diet, and promoted an amelioration of anthropometric and laboratorial parameters.

Introdução: Artrite reumatoide é uma doença inflamatória crônica associada a alterações no metabolismo proteico e energético. Objetivos: Investigar a preferência alimentar durante o desenvolvimento da inflamação crônica em ratas com artrite induzida por colágeno. Métodos: Ratas Wistar fêmeas foram alocadas em dois grupos: controle (CO, n=10) e artrite induzida por colágeno (CIA; n=11) e expostas simultaneamente a quatro diferentes dietas (padrão, hipercalórica, hiperlipidica e hiperproteica). Durante o período experimental foi observado dados clínicos da doença, consumo alimentar, peso corporal e parâmetros bioquímicos, bem como, peso muscular esquelético ao final do experimento. Os testes estatísticos realizados foram ANOVA de duas vias e test-t e nível de significância estabelecido para estes testes foi de 95%. Resultados: Os animais com artrite induzida demostram redução voluntária da ingestão total de alimento, redução do peso corporal e redução da relação sarcossomática quando comparados aos animais controles. Ainda, o grupo artrite aumentou o relativo consumo de dieta hiperproteíca, diminuiu as concentrações séricas de creatinina, triglicerídeos e glicose. Conclusão: Condições inflamatórias crônicas como a artrite reumatoide causam alterações no metabolismo energético e proteíco e estas alterações fisiológicas podem induzir a uma mudança na escolha alimentar. / Background: Rheumatoid arthritis is a chronic inflammatory disease associated with changes in energy and protein metabolism. Objective: To investigate food preferences during the development of chronic inflammation in rats with collagen-induced arthritis (CIA). Methods: Female Wistar rats were separated into two groups, control (CO, n=10) and CIA (n=11), and were simultaneously exposed to four different diets (standard, hypercaloric, hyperlipidic and hyperproteic). During the experimental period was observed clinical evidence of disease, food intake, body weight and biochemical parameters, as well as skeletal muscle weight at the end of the experiment. Statistical tests were two-away ANOVA and t-test and significance level for these tests was 95%. Results: CIA animals demonstrate voluntary reduction in total food intake, reduced body weight and reduced relative muscle weight compared to CO animals. In addition, CIA animals increased relative comsuption of high protein diet, decreased serum concentrations creatinine, triglycerides and glucose. Conclusion: Chronic inflammatory conditions such as rheumatoid arthritis cause changes in protein and energy metabolism, and these physiological alterations may induce a change in food choice.

Introdução: Artrite reumatoide é uma doença inflamatória crônica associada a alterações no metabolismo proteico e energético. Objetivos: Investigar a preferência alimentar durante o desenvolvimento da inflamação crônica em ratas com artrite induzida por colágeno. Métodos: Ratas Wistar fêmeas foram alocadas em dois grupos: controle (CO, n=10) e artrite induzida por colágeno (CIA; n=11) e expostas simultaneamente a quatro diferentes dietas (padrão, hipercalórica, hiperlipidica e hiperproteica). Durante o período experimental foi observado dados clínicos da doença, consumo alimentar, peso corporal e parâmetros bioquímicos, bem como, peso muscular esquelético ao final do experimento. Os testes estatísticos realizados foram ANOVA de duas vias e test-t e nível de significância estabelecido para estes testes foi de 95%. Resultados: Os animais com artrite induzida demostram redução voluntária da ingestão total de alimento, redução do peso corporal e redução da relação sarcossomática quando comparados aos animais controles. Ainda, o grupo artrite aumentou o relativo consumo de dieta hiperproteíca, diminuiu as concentrações séricas de creatinina, triglicerídeos e glicose. Conclusão: Condições inflamatórias crônicas como a artrite reumatoide causam alterações no metabolismo energético e proteíco e estas alterações fisiológicas podem induzir a uma mudança na escolha alimentar. / Background: Rheumatoid arthritis is a chronic inflammatory disease associated with changes in energy and protein metabolism. Objective: To investigate food preferences during the development of chronic inflammation in rats with collagen-induced arthritis (CIA). Methods: Female Wistar rats were separated into two groups, control (CO, n=10) and CIA (n=11), and were simultaneously exposed to four different diets (standard, hypercaloric, hyperlipidic and hyperproteic). During the experimental period was observed clinical evidence of disease, food intake, body weight and biochemical parameters, as well as skeletal muscle weight at the end of the experiment. Statistical tests were two-away ANOVA and t-test and significance level for these tests was 95%. Results: CIA animals demonstrate voluntary reduction in total food intake, reduced body weight and reduced relative muscle weight compared to CO animals. In addition, CIA animals increased relative comsuption of high protein diet, decreased serum concentrations creatinine, triglycerides and glucose. Conclusion: Chronic inflammatory conditions such as rheumatoid arthritis cause changes in protein and energy metabolism, and these physiological alterations may induce a change in food choice.

Background: Low protein diet is one of the treatments for patients with chronic kidney disease during the pre-dialysis period. Studies about this subject have been published for more than 20 years, but the conclusions about its effect and the most appropriate composition are not clear. A low-protein diet is recommended for some patients at the Nephrology Clinic of General University Hospital. These patients are educated and re- educated by a nutrition therapist who also controls their food intake through a food diary. Objectives: To evaluate the effect of low-protein diet on the progression of chronic kidney disease in our conditions and to compare the results with the control group. Furthermore, to evaluate the nutritional status of these patients and the influence of the diet on it. Last but not least, describe a set of patients coming to education about low-protein diet. Methods: The input data was retrospectively retrieved from the medical records of patients who attended medical checks at the Nephrology Clinic of General University Hospital between 10/2016 and 3/2018. A group of 15 patients with a low-protein diet was compared with a control group of 15 patients who did not receive low-protein diet education. The main data collected was year of birth, estimated GFR, urea, creatinine, albumin,...

The effect of the dietary macronutrient composition on weight loss has been a controversial issue for decades. During that time, a high-protein, high-fat, and low-carbohydrate diet has been one of the more popular weight loss diets with the public. We hypothesized that a computer simulation model using STELLA software could help to better understanding the effect of the dietary macronutrient composition on weight loss. We calculated daily total oxidation instead of total energy expenditure as others have done based on the facts that carbohydrate, fat, and protein intake influence carbohydrate, fat, and protein oxidation. In order to create a simple and accurate model comparing dietary macronutrient composition effects, we eliminated exercise as a factor and focused on a sedentary population. The model was validated by five sets of published human data. Following model validation, simulations were carried out to compare the traditional high-carbohydrate diet recommended by the American Dietetic Association and two well-known high-protein diets (Atkins and the Zone diet). The results of computer simulation suggested that the lean tissue retention effect of a high-protein diet, especially with a lower-fat diet, compared with a traditional high carbohydrate diet over 6 months.

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As abelhas são consideradas os polinizadores mais importantes das culturas agrícolas ao redor do mundo e os mais efetivos. As necessidades nutricionais desses animais são atendidas através da coleta de néctar (transportado à colônia e armazenado nos favos) e pólen (consumido após a realização de processos fermentativos de microrganismos, denominando-se beebread ou pão de abelha). O beebread possui uma atratividade natural a essas abelhas. Com o desaparecimento das abelhas, pela falta de alimento disponível, entre outras causas, a alimentação suplementar auxilia apicultores na manutenção dessas colônias em períodos críticos, porém esses suplementos muitas vezes não possuem valor nutritivo adequado e fraca atratividade. Verificar assim quais os compostos voláteis presentes no beebread de diferentes regiões do Brasil e uma dieta fermentada a base desse pólen, faz-se hoje uma importante ferramenta para tentar elucidar o problema da atratividade. Foram feitas análises de atratividade, através de testes em túnel Y com duas dietas artificiais: uma dieta não fermentada e outra fermentada com o próprio beebread, durante quatro dias; análises cromatográficas, com beebread coletado de colônias de abelhas A. mellifera em: Ribeirão Preto/São Paulo; Mossoró/Rio Grande do Norte; Muzambinho/Minas Gerais; Porto Alegre/Rio Grande do Sul; análise polínica das amostras de beebread de todas as localidades. Os testes em túnel Y confirmaram que as abelhas são atraídas pelo cheiro da dieta fermentada, sendo que quanto mais tempo permanecem sem alimentação proteica, mais rapidamente é a escolha do local onde se encontra a dieta fermentada. Já as análises químicas apontaram que tanto a dieta fermentada quanto o beebread coletado nas diferentes localidades possuem alguns compostos voláteis em comum, oriundos principalmente de fermentação: Acetoína, Ácido Acético e 2,3-Butanodiol. Sendo que a classe química que esteve mais presente foi a de terpenoides. A análise polínica das amostras de beebread confirmou os dados obtidos pela análise química. Nossos dados indicam a grande importância da gama de compostos encontrados no beebread e a presença daqueles que indicam a fermentação. Assim, saber qual desses compostos voláteis são atrativos às abelhas será fundamental para a liofilização dos mesmos e adicioná-los às rações proteicas artificiais, tornando-as mais palatáveis e atrativas para esses insetos. / Honey bees are considered to be the most important and most effective pollinators of agricultural crops throughout the world. The nutritional necessities of these insects are met by collecting nectar (transported to the colony and stored in the comb) and pollen (consumed after it has been fermented by microorganisms, becoming bee bread). Bee bread contains substances that are attractive to the bees. As the increasing need for bees has become hard to meet because of a lack of natural food sources to sustain their colonies, it has become increasingly common for beekeepers to provide pollen substitutes. However, nutritional quality and palatability are often inferior to those of bee bread. In a search for key compounds that could help stimulate the bees to consume artificial diets, we examined the volatile compounds present in bee bread and in artificial protein diets that had been fermented with microorganisms present in bee bread. Attractiveness of fermented versus unfermented artificial protein diets for honey bees was compared using a Y odor choice test, for four days. Additionally, chromatographic analyses were made of bee bread collected from apiaries located in Ribeirão Preto, São Paulo, Mossoró, Rio Grande do Norte, Muzambinho, Minas Gerais, and Porto Alegre, Rio Grande do Sul. Pollen analyses were made of all bee bread samples to determine plant origin. The bees preferred the odors from fermented compared to unfermented diet. The rapidity with which they made this choice was positively correlated with the time that they remained without protein food. Several of the volatiles from bee bread from the different regions of the country were similar, despite considerably different contributing pollen species. These volatiles were also found in the fermented pollen substitute diet, indicating that they were products of fermentation; these included acetoin, ascetic acid and 2,3-butanediol. The most common class of volatiles in these materials was terpenoids. There was a large variety of volatile compounds in the bee bread samples and in the fermented bee diet; these included substances that are a result of fermentation. A next step would be to determine which of these substances are most attractive to bees that require protein, so that they can be added to artificial bee diets in order to make them more palatable and useful.

As abelhas são consideradas os polinizadores mais importantes das culturas agrícolas ao redor do mundo e os mais efetivos. As necessidades nutricionais desses animais são atendidas através da coleta de néctar (transportado à colônia e armazenado nos favos) e pólen (consumido após a realização de processos fermentativos de microrganismos, denominando-se beebread ou pão de abelha). O beebread possui uma atratividade natural a essas abelhas. Com o desaparecimento das abelhas, pela falta de alimento disponível, entre outras causas, a alimentação suplementar auxilia apicultores na manutenção dessas colônias em períodos críticos, porém esses suplementos muitas vezes não possuem valor nutritivo adequado e fraca atratividade. Verificar assim quais os compostos voláteis presentes no beebread de diferentes regiões do Brasil e uma dieta fermentada a base desse pólen, faz-se hoje uma importante ferramenta para tentar elucidar o problema da atratividade. Foram feitas análises de atratividade, através de testes em túnel Y com duas dietas artificiais: uma dieta não fermentada e outra fermentada com o próprio beebread, durante quatro dias; análises cromatográficas, com beebread coletado de colônias de abelhas A. mellifera em: Ribeirão Preto/São Paulo; Mossoró/Rio Grande do Norte; Muzambinho/Minas Gerais; Porto Alegre/Rio Grande do Sul; análise polínica das amostras de beebread de todas as localidades. Os testes em túnel Y confirmaram que as abelhas são atraídas pelo cheiro da dieta fermentada, sendo que quanto mais tempo permanecem sem alimentação proteica, mais rapidamente é a escolha do local onde se encontra a dieta fermentada. Já as análises químicas apontaram que tanto a dieta fermentada quanto o beebread coletado nas diferentes localidades possuem alguns compostos voláteis em comum, oriundos principalmente de fermentação: Acetoína, Ácido Acético e 2,3-Butanodiol. Sendo que a classe química que esteve mais presente foi a de terpenoides. A análise polínica das amostras de beebread confirmou os dados obtidos pela análise química. Nossos dados indicam a grande importância da gama de compostos encontrados no beebread e a presença daqueles que indicam a fermentação. Assim, saber qual desses compostos voláteis são atrativos às abelhas será fundamental para a liofilização dos mesmos e adicioná-los às rações proteicas artificiais, tornando-as mais palatáveis e atrativas para esses insetos. / Honey bees are considered to be the most important and most effective pollinators of agricultural crops throughout the world. The nutritional necessities of these insects are met by collecting nectar (transported to the colony and stored in the comb) and pollen (consumed after it has been fermented by microorganisms, becoming bee bread). Bee bread contains substances that are attractive to the bees. As the increasing need for bees has become hard to meet because of a lack of natural food sources to sustain their colonies, it has become increasingly common for beekeepers to provide pollen substitutes. However, nutritional quality and palatability are often inferior to those of bee bread. In a search for key compounds that could help stimulate the bees to consume artificial diets, we examined the volatile compounds present in bee bread and in artificial protein diets that had been fermented with microorganisms present in bee bread. Attractiveness of fermented versus unfermented artificial protein diets for honey bees was compared using a Y odor choice test, for four days. Additionally, chromatographic analyses were made of bee bread collected from apiaries located in Ribeirão Preto, São Paulo, Mossoró, Rio Grande do Norte, Muzambinho, Minas Gerais, and Porto Alegre, Rio Grande do Sul. Pollen analyses were made of all bee bread samples to determine plant origin. The bees preferred the odors from fermented compared to unfermented diet. The rapidity with which they made this choice was positively correlated with the time that they remained without protein food. Several of the volatiles from bee bread from the different regions of the country were similar, despite considerably different contributing pollen species. These volatiles were also found in the fermented pollen substitute diet, indicating that they were products of fermentation; these included acetoin, ascetic acid and 2,3-butanediol. The most common class of volatiles in these materials was terpenoids. There was a large variety of volatile compounds in the bee bread samples and in the fermented bee diet; these included substances that are a result of fermentation. A next step would be to determine which of these substances are most attractive to bees that require protein, so that they can be added to artificial bee diets in order to make them more palatable and useful.

L'encéphalopathie hépatique (EH) est une complication grave de la cirrhose, provoquant des troubles de mémoire, de coordination motrice et de sommeil, avec une progression vers le coma et la mort. Le stress oxydatif dû au foie défaillant et l'ammoniac provenant de la dégradation des protéines alimentaires sont des facteurs pathogènes connus. Simultanément, l'hyperammoniémie et la malnutrition protéino-calorique contribuent à la sarcopénie. Comme les muscles sont le principal mécanisme d'élimination de l'ammoniac pendant la cirrhose, il existe un cercle vicieux où l'hyperammonémie contribue à l'EH et à la sarcopénie, et la sarcopénie contribue à l'hyperammonémie et à l'EH. Notre objectif était de déterminer les effets d’un régime riche en protéines de lactosérum ou de soja administré à long terme, sur la masse musculaire, l'hyperammonémie, et l'EH chez les rats cirrhotiques. Ensuite, nous voulions déterminer les effets d’un gavage aigu de protéines sur l'hyperammonémie et l'EH. Nos résultats montrent qu'un apport élevé en protéines à long terme n'a pas maintenu la masse musculaire ou diminué l'ammoniac, mais que le stress oxydatif a été réduit, ce qui a conduit à la prévention de l'EH, améliorant la mémoire à court et à long terme, l'anxiété, et l'activité locomotrice. Un gavage aigu de protéines chez les rats cirrhotiques n’a pas augmenté l'ammoniac ni précipité l'EH. Cette étude est la première à évaluer l'effet d'un régime élevé en protéines chez des rats cirrhotiques pour observer la masse musculaire, l'ammoniac et l'EH. Nos résultats soutiennent la sécurité et l'efficacité d'une stratégie nutritionnelle riche en protéines dans la cirrhose. / Hepatic encephalopathy (HE) is a serious complication of liver disease, causing impairments in memory, motor coordination, sleep, with progression to coma and death. It affects up to 70% of patients, severely impacting quality of life. Oxidative stress from the failing liver and ammonia from the breakdown of dietary protein are known pathogenic factors. Concurrently, hyperammonemia and protein-calorie malnutrition contribute to muscle wasting, sarcopenia. As muscle is the main clearance mechanism for ammonia during cirrhosis, a vicious cycle exists where elevated ammonia contributes to HE and sarcopenia, and sarcopenia in turn contributes further to hyperammonemia and HE. Our aim was to determine whether long-term high protein whey or soy diets administered from the onset of liver disease in rats could maintain muscle mass, decrease hyperammonemia, and prevent symptoms of HE. Secondly, we wanted to determine the effects an acute load of high protein on hyperammonemia and HE in cirrhotic rodents. Our results show that long-term high protein intake did not maintain muscle mass or decrease ammonia, but oxidative stress was reduced, leading to HE prevention, as shown by the improvement of short- and long-term memory, anxiety, and locomotor activity. An acute load of protein was shown to be safe in cirrhotic rodents, with no increase in ammonia or precipitation of HE. This study is the first of its kind to evaluate the effect of high protein intake in cirrhotic rodents to observe muscle mass, ammonia, and HE. Our results support the safety and efficacy of a high protein nutritional strategy in cirrhosis.

Dans l'alimentation des pays industrialisés, l'apport en protéines est bien supérieur à l'apport nutritionnel conseillé (ANC). De plus, cet apport peut être encore supérieur lors de la consommation de régimes riches en protéines utilisés à des fins de perte de poids par des personnes obèses ou en surpoids. Cependant, les conséquences des régimes riches en protéines au niveau de l'écosystème du gros intestin sont encore très mal connues. Dans la première partie de cette thèse, nous avons étudié l'impact d'un régime hyperprotéique sur le microbiote, le contenu endoluminal du gros intestin et le métabolisme des colonocytes. Les rats ont consommé pendant 15 jours soit un régime hyperprotéique (53% de protéines) soit un régime normoprotéique (14% de protéines). Nous avons observé que le régime hyperprotéique réduit la quantité des groupes bactériens majeurs comme Clostridium coccoides et Clostridium leptum, ainsi que Faecalibacterium prausnitzii dans le microbiote du gros intestin avec conjointement des modifications sur sa biodiversité. En même temps, les quantités des produits finaux de la fermentation des acides aminés par le microbiote, les acides gras à chaîne courte (AGCC) et les acides gras à chaîne branchée sont fortement augmentées. Cependant, l'expression des transporteurs des acides monocarboxyliques et l'oxydation du butyrate par les colonocytes ne sont pas modifiés en lien avec des modifications mineures des concentrations en AGCC dues à une augmentation des contenus du gros intestin après l'ingestion du régime hyperprotéique. Il en résulte une augmentation de l'excrétion des AGCC dans les fèces. Ces phénomènes permettraient une homéostasie du métabolisme du butyrate dans les colonocytes, en lien avec le rôle crucial de cet AGCC sur l'épithélium du côlon. Dans la deuxième partie de cette thèse, nous avons testé l'effet d'un mélange d'acides aminés (Thr, Met et Glu) sur la cicatrisation de la muqueuse colique après une colite induite par le DSS (dextran sodium sulfate) ; un modèle d'étude des maladies inflammatoires intestinales souvent utilisé. Une optimisation de la cicatrisation de la muqueuse intestinale émerge comme une cible thérapeutique, dans la prise en charge de ces maladies. La colite a été induite chez le rat avec 5% (w/v) de DSS pendant 6 jours, puis, à l'arrêt du traitement DSS, les animaux ont soit reçu le mélange d'acides aminé soit l'Ala comme témoin iso-azoté, pendant 3, 7 et 10 jours. Nous avons observé que 10 jours de complément en mélange d'acides aminés améliorent la cicatrisation post-colite, avec des modifications sur le taux de synthèse protéique dans la muqueuse colique, sans toutefois modifier la résolution de l'inflammation. Nos résultats suggèrent que l'utilisation des mélanges d'acides aminés améliore la cicatrisation de la muqueuse colique après colite chimio-induite. / In industrialized countries, protein intake is largely higher than the recommended dietary allowance (RDA). Furthermore, high protein diets are used for their slimming effect by obese or overweight people. However, little is known regarding to the consequences of a high protein diet on the large intestinal ecosystem. We thus study the influence of a high protein diet on the microbiota, on the endoluminal composition of the large intestine and on the butyrate metabolism by isolated colonocytes. Rats received during 15 days either a high protein diet (53% of proteins) or a normo protein diet (14% of proteins). We observed that the quantity of major bacterial groups Clostridium coccoides and Clostridium leptum, but also Faecalibacterium prausnitzii was reduced in the microbiota of the large intestine together with modifications of its biodiversity. In the same time, the quantities of short-chain fatty acids (SCFA) and branched-chain fatty acids, final products of bacterial fermentation of amino acids, were increased. However, the expression of monocarboxylic acid transporters and butyrate oxidation in colonocytes remained unchanged, in association with minor changes of the SCFA concentrations due to marked increase of the weight of the large intestine content. We then observed an increase in the amount of SCFA in the feces. These phenomena would allow homeostatic metabolism of butyrate in colonocytes, in relationship with its crucial role on the colonic epitheliumIn. In the second part of this thesis, we have tested the effects of a mixture of amino acids (Thr, Met and Glu) on the colonic mucosa healing after colitis induced by DSS (dextran sodium sulphate); a model to study intestinal inflammatory bowel diseases largely used. Optimization of intestinal mucosa healing is more and more considered as a therapeutic goal. Colitis was induced in rats by 5% (w/v) DSS during 6 days, then at the end of the treatment with DSS, animals received either the amino acid mixture or Ala as iso-nitrogenous control, during 3, 7 or 10 days. We observed that 10 days amino acid mixture supplementation was able to improve the colonic mucosal healing, with modification of the protein synthesis rate, without however changes in the resolution of inflammation. Our results suggest that the supplementation with the amino acid mixture improve the mucosal healing after experimental colitis.