Murinometric measurements and retroperitoneal adipose tissue in young rats exposed to the high-fat diet: Is there correlation?

AIM: This study aimed to verify the correlation between murine measurements and retroperitoneal adipose tissue in rats exposed to the high-fat diet. Material and methods: Wistar male adult rats, descendants of mothers who consumed a high-fat diet during pregnancy and lactation and fed the same diet after weaning were used. At 60 days of life, body weight, longitudinal axis and waist circumference (WC) were measured. The Body Mass Index (BMI) and the Lee Index were calculated for a posterior analysis of the correlation with the amount of retroperitoneal adipose tissue dissected on the same day. For analysis of the data, the Pearson correlation test was used, considering statistical significance for p <0.05. Results: Body weight had a weak correlation (r= 0.31; p= 0.38) with retroperitoneal adipose tissue. While the longitudinal correlated moderately and negative (r= -0.40; p= 0.25). Abdominal circumference (r= 0.62; p= 0.05), body mass index (r= 0.61; p= 0.03) and Lee (r= 0.69; p= 0.03) correlated moderately and positively with adipose tissue. Conclusion: Among the measured murine measurements, weight and longitudinal axis were not good indicators to represent accumulation of retroperitoneal adipose tissue in rats. However, Lee's index seems to be the best murine marker to diagnose the accumulation of retroperitoneal fat. BMI, CA and Lee index were murine parameters with higher correlation.

Murinometric measurements and retroperitoneal adipose tissue in young rats exposed to the high-fat diet: Is there correlation? / Medidas murinométricas e tecido adiposo retroperitoneal em ratos jovens expostos à dieta hiperlipídica: existe correlação?

Aim: This study aimed to verify the correlation between murine measurements and retroperitoneal adipose tissue in rats exposed to the high-fat diet. Material and methods: Wistar male adult rats, descendants of mothers who consumed a high-fat diet during pregnancy and lactation and fed the same diet after weaning were used. At 60 days of life, body weight, longitudinal axis and waist circumference (WC) were measured. The Body Mass Index (BMI) and the Lee Index were calculated for a posterior analysis of the correlation with the amount of retroperitoneal adipose tissue dissected on the same day. For analysis of the data, the Pearson correlation test was used, considering statistical significance for p<0.05. Results: Body weight had a weak correlation (r= 0.31; p= 0.38) with retroperitoneal adipose tissue. While the longitudinal correlated moderately and negative (r= -0.40; p= 0.25). Abdominal circumference (r= 0.62; p= 0.05), body mass index (r= 0.61; p= 0.03) and Lee (r= 0.69; p= 0.03) correlated moderately and positively with adipose tissue. Conclusion: Among the measured murine measurements, weight and longitudinal axis were not good indicators to represent accumulation of retroperitoneal adipose tissue in rats. However, Lee's index seems to be the best murine marker to diagnose the accumulation of retroperitoneal fat. BMI, CA and Lee index were murine parameters with higher correlation.

Objetivo: Este estudo teve como objetivo verificar a correlação entre medidas murinométricas e tecido adiposo retroperitoneal em ratos expostos à dieta hiperlipídica. Material e métodos: Foram utilizados ratos Wistar machos adultos, descendentes de mães que consumiram dieta hiperlipídica durante a gestação e lactação e alimentados com a mesma dieta após o desmame. Aos 60 dias de vida, foram medidos o peso corporal, o eixo longitudinal e a circunferência da cintura (CC). O Índice de Massa Corporal (IMC) e o Índice de Lee foram calculados para posterior análise da correlação com a quantidade de tecido adiposo retroperitoneal dissecado no mesmo dia. Para análise dos dados, utilizou se o teste de correlação de Pearson, considerando significância estatística para p<0.05. Resultados: O peso corporal apresentou uma correlação fraca (r= 0,31; p= 0,38) com o tecido adiposo retroperitoneal. Enquanto o longitudinal correlacionou moderadamente e negativo (r= -0,40; p= 0,25). A circunferência abdominal (r = 0,62; p = 0,05), índice de massa corporal (r= 0,61; p= 0,03) e Lee (r= 0,69; p= 0,03) correlacionaram-se moderada e positivamente com o tecido adiposo. Conclusão: Entre as medidas murinométricas, o peso e o eixo longitudinal não foram bons indicadores para representar o acúmulo de tecido adiposo retroperitoneal em ratos. No entanto, o índice de Lee parece ser o melhor indicador murinométrico para diagnosticar o acúmulo de gordura retroperitoneal. O IMC, índice de Lee e CA foram parâmetros murinométricos com maior correlação.

Influence of mother nutrition during pregnancy and/or lactation on offspring food preference in experimental models / Influência da nutrição materna durante a gestação e/ou lactação na preferência alimentar da prole em modelos experimentais

Abstract Introduction Understanding associations between food preferences and maternal nutrition during pregnancy and lactation could inform efforts to understanding the obesity mechanisms and provide insight to prevent it. Objective: To identify studies that investigated the effects of nutritional interventions during the pregnancy and lactation on the food preferences of offspring. Method: The review was conducted with search for articles in the databases: Scopus, Pubmed, Medline, LILACS, Scielo and Science Direct. Exclusion criteria were used: reviews, human studies, studies with drugs or other substances not related to food. Results: At the end of the search in the databases, 176 references were found. After use the exclusion criteria, reading the titles, abstracts and full articles, were selected 11 articles to compose the review. Conclusion: The selected studies suggested that unbalanced nutrition in early life alters the food preference and neural components related to the consumption of fatty and sugary foods in offspring rodents.

Resumo Introdução O entendimento das associações entre as preferências alimentares e nutrição materna durante a gravidez e lactação poderia colaborar para a compreensão dos mecanismos da obesidade e fornecer informações para prevenir essa infermidade. Objetivo: Identificar estudos que investigaram os efeitos das intervenções nutricionais durante a gravidez e lactação em preferências alimentares dos descendentes. Método: A revisão foi conduzida com busca de artigos nas bases de dados: Scopus, Pubmed, Medline, Lilacs, Scielo e Science Direct. Os critérios de exclusão utilizados: revisões, estudos em humanos, estudos com drogas ou outras substâncias não-alimentares. Resultados: No final da pesquisa nas bases de dados, 176 referências foram encontradas. Depois de usar os critérios de exclusão, lendo os títulos, resumos e artigos completos, 11 artigos foram selecionados para compor a revisão. Conclusão: Os estudos selecionados sugeriram que a nutrição desequilibrada no início da vida altera a preferência alimentar e componentes neurais relacionadas com o consumo de alimentos gordurosos e açucarados em prole de roedores.

Influence of mother nutrition during pregnancy and/or lactation on offspring food preference in experimental models.

INTRODUCTION: Understanding associations between food preferences and maternal nutrition during pregnancy and lactation could inform efforts to understanding the obesity mechanisms and provide insight to prevent it. Objective: To identify studies that investigated the effects of nutritional interventions during the pregnancy and lactation on the food preferences of offspring. Method: The review was conducted with search for articles in the databases: Scopus, Pubmed, Medline, LILACS, Scielo and Science Direct. Exclusion criteria were used: reviews, human studies, studies with drugs or other substances not related to food. Results: At the end of the search in the databases, 176 references were found. After use the exclusion criteria, reading the titles, abstracts and full articles, were selected 11 articles to compose the review. Conclusion: The selected studies suggested that unbalanced nutrition in early life alters the food preference and neural components related to the consumption of fatty and sugary foods in offspring rodents.

Effects of high-impact exercise on the physical properties of bones of ovariectomized rats fed to a high-protein diet.

The aim of this study was to evaluate the effects of high-impact physical exercise as a prophylactic and therapeutic means in osteopenic bones of rats submitted to ovariectomy and protein diet intake. A total of 64 Wistar rats were divided into eight groups (n = 8 each), being: OVX, ovx, standard diet and sedentary; OVXE, ovx, standard diet and jump; OVXP, ovx, high-protein diet and sedentary; and OVXEP, ovx, high-protein diet and jump; SH, sham, standard diet and sedentary; SHE, sham, standard diet and jump; SHP, sham, high-protein diet and sedentary; and SHEP, sham, high-protein diet and jump. OVX surgery consists of ovariectomy, and sham was the control surgery. The jumping protocol consisted of 20 jumps/day, 5 days/week. The bone structure was evaluated by densitometry, mechanical tests, histomorphometric, and immunohistochemical analyses. A high-protein diet resulted in increased bone mineral density (P = .049), but decreased maximal load (P = .026) and bone volume fraction (P = .023). The benefits of physical exercise were demonstrated by higher values of the maximal load in the trained groups compared to the sedentary groups (P < .001). The sham groups had decreased immunostaining of osteocalcin (P = .004) and osteopontin (P = .010) compared to ovx groups. However, the high-protein diet (P = .005) and jump exercise (P = .017) resulted in lower immunostaining of osteopontin compared to the standard diet and sedentary groups, respectively. In this experimental model, it was concluded that ovariectomy and a high-fat diet can negatively affect bone tissue and the high-impact exercise was not enough to suppress the deleterious effects caused by the protein diet and ovariectomy.

Influence of treadmill training on bone structure under osteometabolic alteration in rats subjected to high-fat diet.

Nutrition and physical training have important roles in the accumulation and maintenance of bone mass. The aim of this study was to evaluate, in ovariectomized rats (OVX), the effects of treadmill training (T) with high-fat diet (F) on weight gain and bone tissue properties with eight groups (n = 10) for 12 weeks: OVX SC (OVX, sedentary lifestyle, diet control); OVX SF; OVX TC; OVX TF; SH SC (SHAM, sedentary lifestyle, diet control); SH SF; SH TC; and SH TF. Weekly weight gain and final body composition were assessed. After euthanasia, tibiae were analyzed. The trained animals had higher body weight (P = 0.001), bone mineral density (P < 0.001), and trabecular bone (P < 0.001). The animals with a high-fat diet showed higher global fat (P < 0.001), percentage of global fat (P < 0.001) and deformation at impact (P = 0.031) and reduced tibial bone mineral content (P = 0.036). Physical training improves bone microarchitecture, without presenting an increase in impact resistance, and a high-fat diet increases body fat and impairs bone mineralization.

Murinometric measurements and retroperitoneal adipose tissue in young rats exposed to the high-fat diet: Is there correlation?

Abstract Aim This study aimed to verify the correlation between murine measurements and retroperitoneal adipose tissue in rats exposed to the high-fat diet. Material and methods: Wistar male adult rats, descendants of mothers who consumed a high-fat diet during pregnancy and lactation and fed the same diet after weaning were used. At 60 days of life, body weight, longitudinal axis and waist circumference (WC) were measured. The Body Mass Index (BMI) and the Lee Index were calculated for a posterior analysis of the correlation with the amount of retroperitoneal adipose tissue dissected on the same day. For analysis of the data, the Pearson correlation test was used, considering statistical significance for p 0.05. Results: Body weight had a weak correlation (r= 0.31; p= 0.38) with retroperitoneal adipose tissue. While the longitudinal correlated moderately and negative (r= -0.40; p= 0.25). Abdominal circumference (r= 0.62; p= 0.05), body mass index (r= 0.61; p= 0.03) and Lee (r= 0.69; p= 0.03) correlated moderately and positively with adipose tissue. Conclusion: Among the measured murine measurements, weight and longitudinal axis were not good indicators to represent accumulation of retroperitoneal adipose tissue in rats. However, Lee's index seems to be the best murine marker to diagnose the accumulation of retroperitoneal fat. BMI, CA and Lee index were murine parameters with higher correlation.

Resumo Objetivo Este estudo teve como objetivo verificar a correlação entre medidas murinométricas e tecido adiposo retroperitoneal em ratos expostos à dieta hiperlipídica. Material e métodos: Foram utilizados ratos Wistar machos adultos, descendentes de mães que consumiram dieta hiperlipídica durante a gestação e lactação e alimentados com a mesma dieta após o desmame. Aos 60 dias de vida, foram medidos o peso corporal, o eixo longitudinal e a circunferência da cintura (CC). O Índice de Massa Corporal (IMC) e o Índice de Lee foram calculados para posterior análise da correlação com a quantidade de tecido adiposo retroperitoneal dissecado no mesmo dia. Para análise dos dados, utilizou-se o teste de correlação de Pearson, considerando significância estatística para p 0.05. Resultados: O peso corporal apresentou uma correlação fraca (r= 0,31; p= 0,38) com o tecido adiposo retroperitoneal. Enquanto o longitudinal correlacionou moderadamente e negativo (r= -0,40; p= 0,25). A circunferência abdominal (r = 0,62; p = 0,05), índice de massa corporal (r= 0,61; p= 0,03) e Lee (r=0,69; p= 0,03) correlacionaram-se moderada e positivamente com o tecido adiposo. Conclusão: Entre as medidas murinométricas, o peso e o eixo longitudinal não foram bons indicadores para representar o acúmulo de tecido adiposo retroperitoneal em ratos. No entanto, o índice de Lee parece ser o melhor indicador murinométrico para diagnosticar o acúmulo de gordura retroperitoneal. O IMC, índice de Lee e CA foram parâmetros murinométricos com maior correlação.

High-impact exercise in rats prior to and during suspension can prevent bone loss

High-impact exercise has been considered an important method for treating bone loss in osteopenic experimental models. In this study, we investigated the effects of osteopenia caused by inactivity in femora and tibiae of rats subjected to jump training using the rat tail suspension model. Eight-week-old female Wistar rats were divided into five groups (n=10 each group): jump training for 2 weeks before suspension and training during 3 weeks of suspension; jump training for 2 weeks before suspension; jump training only during suspension; suspension without any training; and a control group. The exercise protocol consisted of 20 jumps/day, 5 days/week, with a jump height of 40 cm. The bone mineral density of the femora and tibiae was measured by double energy X-ray absorptiometry and the same bones were evaluated by mechanical tests. Bone microarchitecture was evaluated by scanning electron microscopy. One-way ANOVA was used to compare groups. Significance was determined as P<0.05. Regarding bone mineral density, mechanical properties and bone microarchitecture, the beneficial effects were greater in the bones of animals subjected to pre-suspension training and subsequently to training during suspension, compared with the bones of animals subjected to pre-suspension training or to training during suspension. Our results indicate that a period of high impact exercise prior to tail suspension in rats can prevent the installation of osteopenia if there is also training during the tail suspension.

Analysis of fracture healing in osteopenic bone caused by disuse: experimental study

Osteoporosis has become a serious global public health issue. Hence, osteoporotic fracture healing has been investigated in several previous studies because there is still controversy over the effect osteoporosis has on the healing process. The current study aimed to analyze two different periods of bone healing in normal and osteopenic rats. Sixty, 7-week-old female Wistar rats were randomly divided into four groups: unrestricted and immobilized for 2 weeks after osteotomy (OU2), suspended and immobilized for 2 weeks after osteotomy (OS2), unrestricted and immobilized for 6 weeks after osteotomy (OU6), and suspended and immobilized for 6 weeks after osteotomy (OS6). Osteotomy was performed in the middle third of the right tibia 21 days after tail suspension, when the osteopenic condition was already set. The fractured limb was then immobilized by orthosis. Tibias were collected 2 and 6 weeks after osteotomy, and were analyzed by bone densitometry, mechanical testing, and histomorphometry. Bone mineral density values from bony calluses were significantly lower in the 2-week post-osteotomy groups compared with the 6-week post-osteotomy groups (multivariate general linear model analysis, P<0.000). Similarly, the mechanical properties showed that animals had stronger bones 6 weeks after osteotomy compared with 2 weeks after osteotomy (multivariate general linear model analysis, P<0.000). Histomorphometry indicated gradual bone healing. Results showed that osteopenia did not influence the bone healing process, and that time was an independent determinant factor regardless of whether the fracture was osteopenic. This suggests that the body is able to compensate for the negative effects of suspension.

High-impact exercise in rats prior to and during suspension can prevent bone loss.

High-impact exercise has been considered an important method for treating bone loss in osteopenic experimental models. In this study, we investigated the effects of osteopenia caused by inactivity in femora and tibiae of rats subjected to jump training using the rat tail suspension model. Eight-week-old female Wistar rats were divided into five groups (n=10 each group): jump training for 2 weeks before suspension and training during 3 weeks of suspension; jump training for 2 weeks before suspension; jump training only during suspension; suspension without any training; and a control group. The exercise protocol consisted of 20 jumps/day, 5 days/week, with a jump height of 40 cm. The bone mineral density of the femora and tibiae was measured by double energy X-ray absorptiometry and the same bones were evaluated by mechanical tests. Bone microarchitecture was evaluated by scanning electron microscopy. One-way ANOVA was used to compare groups. Significance was determined as P<0.05. Regarding bone mineral density, mechanical properties and bone microarchitecture, the beneficial effects were greater in the bones of animals subjected to pre-suspension training and subsequently to training during suspension, compared with the bones of animals subjected to pre-suspension training or to training during suspension. Our results indicate that a period of high impact exercise prior to tail suspension in rats can prevent the installation of osteopenia if there is also training during the tail suspension.

Analysis of fracture healing in osteopenic bone caused by disuse: experimental study.

Osteoporosis has become a serious global public health issue. Hence, osteoporotic fracture healing has been investigated in several previous studies because there is still controversy over the effect osteoporosis has on the healing process. The current study aimed to analyze two different periods of bone healing in normal and osteopenic rats. Sixty, 7-week-old female Wistar rats were randomly divided into four groups: unrestricted and immobilized for 2 weeks after osteotomy (OU2), suspended and immobilized for 2 weeks after osteotomy (OS2), unrestricted and immobilized for 6 weeks after osteotomy (OU6), and suspended and immobilized for 6 weeks after osteotomy (OS6). Osteotomy was performed in the middle third of the right tibia 21 days after tail suspension, when the osteopenic condition was already set. The fractured limb was then immobilized by orthosis. Tibias were collected 2 and 6 weeks after osteotomy, and were analyzed by bone densitometry, mechanical testing, and histomorphometry. Bone mineral density values from bony calluses were significantly lower in the 2-week post-osteotomy groups compared with the 6-week post-osteotomy groups (multivariate general linear model analysis, P<0.000). Similarly, the mechanical properties showed that animals had stronger bones 6 weeks after osteotomy compared with 2 weeks after osteotomy (multivariate general linear model analysis, P<0.000). Histomorphometry indicated gradual bone healing. Results showed that osteopenia did not influence the bone healing process, and that time was an independent determinant factor regardless of whether the fracture was osteopenic. This suggests that the body is able to compensate for the negative effects of suspension.