Indução de estresse oxidativo em modelo agudo de hipertriptofanemia

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Metabarcoding reveals that a non-nutritive sweetener and sucrose yield similar gut microbiota patterns in Wistar rats

The effects of non-nutritive sweeteners (NNS) on the gut microbiota are an area of increasing research interest due to their potential influence on weight gain, insulin resistance, and inflammation. Studies have shown that mice and rats fed saccharin develop weight gain and metabolic alterations, possibly related to changes in gut microbiota. Here, we hypothesized that chronic exposure to a commercial NNS would change the gut microbiota composition in Wistar rats when compared to sucrose exposure. To test this hypothesis, Wistar rats were fed either NNS- or sucrose-supplemented yogurt for 17 weeks alongside standard chow (ad libitum). The gut microbiome was assessed by 16S rDNA deep sequencing. Assembly and quantification were conducted using the Brazilian Microbiome Project pipeline for Ion Torrent data with modifications. Statistical analyses were performed in the R software environment. We found that chronic feeding of a commercial NNS-sweetened yogurt to Wistar rats, within the recommended dose range, did not significantly modify gut microbiota composition in comparison to sucrose-sweetened yogurt. Our findings do not support the hypothesis that moderate exposure to NNS is associated with changes in gut microbiota pattern compared to sucrose, at least in this experimental model.

Efeito da suplementação isocalórica de sacarina e sacarose no ganho de peso, ingestão calórica, tolerância à glicose e consumo basal de oxigênio em ratos Wistar

Introdução: O uso de adoçantes não calóricos (ANC) pode interferir na regulação do apetite, promovendo maior ingestão alimentar, maior ganho de peso (GP) e maior adiposidade. Em estudos anteriores, do nosso grupo, os resultados mostraram que os animais que consumiram iogurte com sacarina e aspartame tiveram um maior ganho de peso comparado ao grupo que usou sacarose. Porém, como o consumo calórico total foi semelhante entre os grupos, o aumento de peso não pôde ser explicado pelo aumento de ingestão calórica. Concluímos, então, que o aumento de peso poderia estar associado à redução do gasto energético induzido pelo adoçante artificial. Estudos anteriores já sugeriram que a sacarina poderia induzir um aumento de peso, porém nenhum estudo até o momento avaliou o consumo de oxigênio basal dos animais. Nesse sentido, é possível que a sacarina possa estar determinando a redução do gasto energético e possivelmente contribuindo para um aumento na glicemia. Desse modo, o presente estudo contempla analisar o efeito da sacarina no consumo basal de oxigênio. Materiais e Métodos: Foi realizado um experimento controlado com 37 ratos Wistar machos adultos pesando entre 180 e 220 g, que foram divididos aleatoriamente em três grupos de acordo com o tipo de exposição tanto para adoçante não calórico (sacarina-SAC), adoçante calórico (sacarose-SUC) ou controle (CONT). Os suplementos foram oferecidos diariamente durante um período de 12 semanas. O ganho de peso, ingestão calórica e controle hídrico foram determinados semanalmente, o consumo basal de oxigênio determinado em repouso (VO2) e RER foram medidos no início do estudo, 5 e 12 semanas, e o teste de tolerância à glicose oral foi determinada nas semanas 6 e 12. Resultados: O uso de sacarina promoveu maior ganho de peso que a sacarose (p=0,031). A ingestão calórica total (kcal/g) diferiu entre os grupos (p=0,029). Os animais que consumiram sacarina ingeriram mais ração. Os grupos apresentaram diferenças quanto à ingestão hídrica, sendo o grupo sacarina com o maior consumo (ml/g) (p=0,018). Entretanto, o consumo de oxigênio e o quociente respiratório não foram significativos. Conclusão: O ganho de peso cumulativo nos animais que consumiram sacarina não pode ser atribuído a uma redução no dispêndio de energia, medida pelo consumo de oxigênio, mas sim pelo aumento da ingestão alimentar e hídrica.Introduction: The use of non-caloric sweeteners (ANC) can interfere with the regulation of appetite, promoting greater food intake, greater weight gain (WG) and increased adiposity. In previous data, the results showed that the animals that consumed yogurt saccharin and aspartame had a greater increase in weight compared to the group using sucrose. However, as the total calorie intake was similar between the groups, the weight increase could not be explained by the increase in caloric intake. We concluded that weight gain may be associated with decreased energy expenditure induced by artificial sweetener. Previous studies have suggested that saccharin could induce weight gain, but no study to date has evaluated the consumption of oxygen basal animals. In this sense, it is possible that saccharin may be determining reduction in energy expenditure and possibly contributing to an increase in blood glucose. Thus, this study include saccharin analyze the effect on basal oxygen consumption. Materials and Methods: We conducted a controlled experiment with 37 adult male Wistar rats weighing 180-220 g were randomly divided into three groups according to the type of exposure for both non-caloric sweetener (sugar-SAC), calorie sweetener (sucrose-SUC) or control (CONT). The supplements were given daily over a period of 12 weeks. Weight gain, food intake and water control were determined weekly, basal oxygen consumption determined at rest (VO2) and RER were measured at baseline, 5 and 12 weeks and tolerance test oral glucose was determined at week 6 and 12. Results: The use of saccharin promoted greater weight gain than sucrose (p =0.031). The total caloric intake (kcal/g) differ between the groups (p = 0.029), the animals that consumed saccharin ate more food. The groups differed in water intake, and the sugar group with the highest consumption (ml/g) (p = 0.018). However, the oxygen consumption and the respiratory exchange ratio were not significant. Conclusion: The cumulative weight gain in the animals fed saccharin can not be attributed to a reduction in energy expenditure, measured by oxygen consumption, but can be explained by increased food and water intake

Indução de estresse oxidativo em modelo agudo de hipertriptofanemia

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Associações entre ingestão energética, proteica e de fósforo em pacientes portadores de doença renal crônica em tratamento hemodialítico Associations between energy, protein, and phosphorus intakes in patients with chronic kidney disease on hemodialysis

INTRODUÇÃO: A nutrição desempenha papel fundamental nas doenças renais. A recomendação nutricional deve ofertar uma dieta hiperproteica, adequada em energia e fósforo segundo o Kidney Disease Outcomes Quality Initiative (K/DOQI). É necessário controlar e/ou prevenir as complicações da Doença Renal Crônica (DRC), pois ela impõe desafios clínicos diretamente ligados ao estado nutricional. OBJETIVO: Investigar as associações entre a ingestão energética, proteica e de fósforo em pacientes em hemodiálise (HD). PACIENTES E MÉTODOS: Estudo observacional envolvendo 72 pacientes em HD, em dois hospitais de Porto Alegre/RS/Brasil. Foram coletados dados referentes ao perfil antropométrico (peso, altura e índice de massa corporal - IMC) e do registro alimentar de três dias (ingestão de energia, proteína e fósforo). O teste de correlação de Spearman foi utilizado para avaliar as associações entre as variáveis do registro alimentar (p < 0,05). RESULTADOS: A ingestão energética, proteica e de fósforo foi, respectivamente, de: 28 ± 10,0 kcal/kg, 1,1 ± 0,4 g ptn/kg, 958 ± 374 mg/dia, estando os níveis de energia e proteína abaixo das recomendações do K/DOQI. Observou-se correlação positiva forte entre as variáveis. DISCUSSÃO: O perfil no tratamento nutricional é fundamental, pois houve correlações entre os nutrientes. É importante salientar que as recomendações do K/DOQI não conseguem ser atingidas pelos pacientes. CONCLUSÃO: Há associação positiva entre a ingestão de energia, proteína e fósforo na alimentação de pacientes em HD. O controle desses nutrientes na dieta é essencial, pois auxilia no controle das complicações relacionadas com a DRC. Assim, a avaliação nutricional é importante nas unidades de diálise para definir o perfil dietético dos pacientes e que seja feito o ajuste de suas prescrições.<br>INTRODUCTION: Nutrition plays an important role in kidney disease. The nutritional recommendation is to offer a high-protein diet, adequate in energy and phosphorus according to the Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines. Control and/or prevention of the complications of chronic kidney disease (CKD) are essential, because CKD poses clinical challenges directly related to the nutritional status. OBJECTIVE: To investigate the possible associations between energy, protein, and phosphorus intakes in hemodialysis (HD) patients. METHODS: Observational study involving 72 HD patients from two hospitals in the city of Porto Alegre, Brazil. Anthropometric data [weight, height, body mass index (IMB)] were collected and three-day food intake (daily energy, protein, and phosphorus intakes) was recorded. Spearman correlation was used to evaluate associations between food intake variables (p < 0.05). RESULTS: The energy, protein, and phosphorus intakes were 28 ± 10 kcal/kg/day, 1,1 ± 0.4 g protein/kg, and 958 ± 374 mg/day, respectively, and the first two were below the K/DOQUI recommendations. A strong positive correlation was observed between the variables. DISCUSSION: Assessing the nutritional profile is essential, because correlations between nutrients occur. It is worth emphasizing that the K/DOQI guidelines are not met by the patients. CONCLUSION: A positive association between the intakes of energy, protein, and phosphorus is observed in the diet of HD patients. The dietary control of these nutrients is essential to manage CKD complications. Therefore, nutritional evaluation in dialysis units is crucial to define the dietary profile of patients and to adjust their prescriptions

Metabarcoding reveals that a non-nutritive sweetener and sucrose yield similar gut microbiota patterns in Wistar rats

The effects of non-nutritive sweeteners (NNS) on the gut microbiota are an area of increasing research interest due to their potential influence on weight gain, insulin resistance, and inflammation. Studies have shown that mice and rats fed saccharin develop weight gain and metabolic alterations, possibly related to changes in gut microbiota. Here, we hypothesized that chronic exposure to a commercial NNS would change the gut microbiota composition in Wistar rats when compared to sucrose exposure. To test this hypothesis, Wistar rats were fed either NNS- or sucrose-supplemented yogurt for 17 weeks alongside standard chow (ad libitum). The gut microbiome was assessed by 16S rDNA deep sequencing. Assembly and quantification were conducted using the Brazilian Microbiome Project pipeline for Ion Torrent data with modifications. Statistical analyses were performed in the R software environment. We found that chronic feeding of a commercial NNS-sweetened yogurt to Wistar rats, within the recommended dose range, did not significantly modify gut microbiota composition in comparison to sucrose-sweetened yogurt. Our findings do not support the hypothesis that moderate exposure to NNS is associated with changes in gut microbiota pattern compared to sucrose, at least in this experimental model.