Capybara Oil Improves Hepatic Mitochondrial Dysfunction, Steatosis, and Inflammation in a Murine Model of Nonalcoholic Fatty Liver Disease.

Nonalcoholic fatty liver disease (NAFLD) is recognized as the most common cause of liver dysfunction worldwide and is commonly associated with obesity. Evidences suggest that NAFLD might be a mitochondrial disease, which contributes to the hepatic steatosis, oxidative stress, cytokine release, and cell death. Capybara oil (CO) is a rich source of polyunsaturated fatty acids (PUFA), which is known to improve inflammation and oxidative stress. In order to determine the effects of CO on NAFLD, C57Bl/6 mice were divided into 3 groups and fed a high-fat diet (HFD) (NAFLD group and NAFLD + CO group) or a control diet (CG group) during 16 weeks. The CO (1.5 g/kg/daily) was administered by gavage during the last 4 weeks of the diet protocol. We evaluated plasma liver enzymes, hepatic steatosis, and cytokine expression in liver as well as hepatocyte ultrastructural morphology and mitochondrial function. CO treatment suppressed hepatic steatosis, attenuated inflammatory response, and decreased plasma alanine aminotransferase (ALT) in mice with NAFLD. CO was also capable of restoring mitochondrial ultrastructure and function as well as balance superoxide dismutase and catalase levels. Our findings indicate that CO treatment has positive effects on NAFLD improving mitochondrial dysfunction, steatosis, acute inflammation, and oxidative stress.

Overnutrition during lactation leads to impairment in insulin signaling, up-regulation of GLUT1 and increased mitochondrial carbohydrate oxidation in heart of weaned mice.

Several studies have demonstrated that overnutrition during early postnatal period can increase the long-term risk of developing obesity and cardiac disorders, yet the short-term effects of postnatal overfeeding in cardiac metabolism remains unknown. The aim of our study was to investigate the cardiac metabolism of weaned mice submitted to overnutrition during lactation, particularly as to mitochondrial function, substrate preference and insulin signaling. Postnatal overfeeding was induced by litter size reduction in mice at postnatal day 3. At 21 days of age (weaning), mice in the overfed group (OG) presented biometric and biochemical parameters of obesity, including increased body weight, visceral fat, liver weight and increased left ventricle weight/tibia length ratio; indicating cardiac hypertrophy, hyperglycemia, hyperinsulinemia and increased liver glycogen content compared to control group. In the heart, we detected impaired insulin signaling, mainly due to decreased IRß, pTyr-IRS1, PI3K, GLUT4 and pAkt/Akt and increased PTP1B, GLUT1 and pAMPKα/AMPKα content. Activities of lactate dehydrogenase and citrate synthase were increased, accompanied by enhanced carbohydrate oxidation, as observed by high-resolution respirometry. Moreover, OG hearts had lower CPT1, PPARα and increased UCP2 mRNA expression, associated with increased oxidative stress (4-HNE content), BAX/BCL2 ratio and cardiac fibrosis. Ultrastructural analysis of OG hearts demonstrated mild mitochondrial damage without alterations in OXPHOS complexes. In conclusion, overnutrition during early life induces short-term metabolic disturbances, impairment in heart insulin signaling, up-regulates GLUT-1 and switch cardiac fuel preference in juvenile mice.

Heart energy metabolism impairment in Western-diet induced obese mice.

Nutritional transition has contributed to growing obesity, mainly by changing eating habits of the population. The mechanisms by which diet-induced obesity leads to cardiac injury are not completely understood, but it is known that obesity is associated to impaired cardiac function and energy metabolism, increasing morbidity and mortality. Therefore, our study aimed to investigate the mechanisms underlying cardiac metabolism impairment related to Western diet-induced obesity. After weaning, male Swiss mice were fed a Western diet for 16 weeks in order to induce obesity. After this period, the content of proteins involved in heart energy metabolism GLUT1, cytosolic lysate and plasma membrane GLUT4, AMPK, pAMPK, IRß, IRS-1, PGC-1α, CPT1 and UCP2 was evaluated. Also, the oxidative phosphorylation of myocardial fibers was measured by high-resolution respirometry. Mice in the Western diet group (WG) presented altered biometric parameters compared to those in control group, including higher body weight, increased myocardial lipid deposition and glucose intolerance, which demonstrate the obesogenic role of Western diet. WG presented increased CPT1 and UCP2 contents and decreased IRS-1, plasma membrane GLUT4 and PGC-1α contents. In addition, WG presented cardiac mitochondrial dysfunction and reduced biogenesis, demonstrating a lower capacity of carbohydrates and fatty acid oxidation and also decreased coupling between oxidative phosphorylation and adenosine triphosphate synthesis. Cardiac metabolism impairment related to Western diet-induced obesity is probably due to damaged myocardial oxidative capacity, reduced mitochondrial biogenesis and mitochondria uncoupling, which compromise the bioenergetic metabolism of heart.

Lymphocytes mitochondrial physiology as biomarker of energy metabolism during fasted and fed conditions.

Mitochondria are central coordinators of energy metabolism, and changes of their physiology have long been associated with metabolic disorders. Thus, observations of energy dynamics in different cell types are of utmost importance. Therefore, tools with quick and easy handling are needed for consistent evaluations of such interventions. In this paper, our main hypothesis is that during different nutritional situations lymphocytes mitochondrial physiology could be associated with the metabolism of other cell types, such as cardiomyocytes, and consequently be used as metabolic biomarker. Blood lymphocytes and heart muscle fibers were obtained from both fed and 24 h-fasted mice, and mitochondrial analysis was assessed by high-resolution respirometry and western blotting. Carbohydrate-linked oxidation and fatty acid oxidation were significantly higher after fasting. Carnitine palmitoil transferase 1 and uncouple protein 2 contents were increased in the fasted group, while the glucose transporters 1 and 4 and the ratio phosphorylated AMP-activated protein kinase/AMPK did not change between groups. In summary, under a nutritional status modification, mitochondria demonstrated earlier adaptive capacity than other metabolic sensors such as glucose transporters and AMPK, suggesting the accuracy of mitochondria physiology of lymphocytes as biomarker for metabolic changes.

Ghrelin signaling in heart remodeling of adult obese mice.

Ghrelin, an endogenous ligand of the growth hormone secretagogue receptor (GHS-R), has been suggested to be associated to obesity, insulin secretion, cardiovascular growth and homeostasis. GHS-R has been found in most of the tissues, and among the hormone action it is included the regulation of heart energy metabolism. Therefore, hypernutrition during early life leads to obesity, induces cardiac hypertrophy, compromises myocardial function, inducing heart failure in adulthood. We examined ghrelin signaling process in cardiac remodeling in these obese adult mice. The cardiomyocytes (cmy) of left ventricle were analyzed by light microscopy and stereology, content and phosphorilation of cardiac proteins: ghrelin receptor (growth hormone secretagogue receptor 1a, GHSR-1a), protein kinase B (AKT and pAKT), phosphatidil inositol 3 kinase (PI3K), AMP-activated protein kinase (AMPK and pAMPK) and actin were achieved by Western blotting. GHSR-1a gene expression was analyzed by Real Time-PCR. We observed hyperglycemia and higher liver and visceral fat weight in obese when compared to control group. Obese mice presented a marked increase in heart weight/tibia length, indicating an enlarged heart size or a remodeling process. Obese mice had increased GHSR-1a content and expression in the heart associated to PI3K content and increased AKT content and phosphorylation. In contrast, AMPK content and phosphorylation in heart was not different between experimental groups. Ghrelin plasma levels in obese group were decreased when compared to control group. Our data suggest that remodeled myocardial in adult obese mice overnourished in early life are associated with higher phosphorylation of GHSR-1a, PI3K and AKT but not with AMPK.

Early life overfeeding decreases acylated ghrelin circulating levels and upregulates GHSR1a signaling pathway in white adipose tissue of obese young mice.

Ghrelin is a hormone synthesized by the stomach that acts in different tissues via a specific receptor (GHS-R1a), including hypothalamus and adipose tissue. For instance, recent reports have shown that ghrelin has a direct action on hypothalamic regulation of food intake mainly inducing an orexigenic effect. On the other hand, ghrelin also modulates energy stores and expenditure in the adipocytes. This dual action has suggested that this hormone may act as a link between the central nervous system and peripheral mechanisms. Furthermore, concerning nutritional disorders, it has been suggested that obesity may be considered an impairment of the above cited link. Therefore, considering that neonatal overfeeding induces obesity in adulthood by unknown mechanisms, in this study we examined the effects of early life overnutrition on the development of obesity and in particular on adipose tissue ghrelin signaling in young mice. Our data demonstrated that overnutrition during early life induces a significant increase in body weight of young mice, starting at 10 days, and this increase in weight persisted until adulthood (90 days of age). In these animals, blood glucose, liver weight and visceral fat weight were found higher at 21 days when compared to the control group. Acylated ghrelin circulating levels were found lower in the young obese pups. In addition, in white adipose tissue ghrelin receptor (GHS-R1a) expression increased and was associated to positive modulation of content and phosphorylation of proteins involved in cell energy store and use as AKT, PI3K, AMPK, GLUT-4, and CPT1. However, PPARγ content decreased in obese group. Basically, we showed that adipose tissue metabolism is altered in early life acquired obesity and probably due to such modification a new pattern of ghrelin signaling pathway takes place.

Maternal protein restriction during early lactation induces changes on neutrophil activation and TNF-alpha production of adult offspring.

Maternal nutritional environmental in early life has been often associated with long term effects on the immune response in adulthood. The effects of maternal protein deprivation during early lactation on neutrophil-mediated innate immunity were investigated in adult rats, offspring of dams fed with a protein-free diet during the first days of lactation (PD), and compared to controls (22% protein diet). Inflamed PD animals showed an inhibited neutrophil migration and an impaired recruitment of leukocytes from bone marrow pool to circulation. In resting conditions, blood neutrophils from PD present reduced phagocytic activity, increased production of O(2) (-) and NO, basal iNOS expression and constitutive NF-kappaB activation. Moreover, PD rats also show high circulating levels of TNF-alpha and increased expression of TNF-alpha mRNA in the spleen and liver. The data indicate that maternal nutritional stress can interfere on the innate immune response in adulthood, imprinting permanent alterations on cytokine production and neutrophil activation.

n-3 polyunsaturated fatty acids in milk is associate to weight gain and growth in premature infants.

BACKGROUND: Linoleic 18:2 (n-6) and alpha-linolenic 18:3 (n-3) essential fatty acids and long-chain polyunsaturated fatty acids (LC-PUFA) are essential nutrients for growth and neonatal development. Consumption of preformed n-3 LC-PUFA has been shown to increase gestational duration and to decrease the incidence of premature birth in human studies. This study evaluated the association of essential fatty acids and LC-PUFA in breast milk on the growth of premature children (weight, height and head circumference). STUDY DESIGN: Thirty-seven premature infants with a gestational age of 37 weeks or less were followed until 6 months of gestational age, adjusted for prematurity. The milk from mothers, weight, height and head circumference measures of children were collected during the follow up. The breast milk fatty acids were quantified by gas-liquid chromatography. RESULTS: Our results showed that total n-3 PUFA was positively associated with weight gain (p = 0.05), height (p = 0.04) and body mass index (BMI) of children (p = 0.05). Our results also indicate that both linoleic acid and total essential fatty acids were positively associated with BMI and head circumference, whereas oleic acid was positively associated only with head circumference. CONCLUSION: These results suggest that the n-3 PUFA composition of milk may be associated with weight gain and growth. Considering the advantages of n-3 LC-PUFA consumption on infant growth and visual function and its association with reduced incidence of premature birth, dietitians should advise pregnant women to increase their intake of foods high in n-3 LC-PUFA.

An 18-mo randomized trial of a low-glycemic-index diet and weight change in Brazilian women.

BACKGROUND: Despite interest in the glycemic index diets as an approach to weight control, few long-term evaluations are available. OBJECTIVE: The objective was to investigate the long-term effect of a low-glycemic-index (LGI) diet compared with that of a high-glycemic-index (HGI) diet; all other dietary components were equal. DESIGN: After a 6-wk run-in, we randomly assigned 203 healthy women [body mass index (in kg/m2): 23-30] aged 25-45 y to an LGI or an HGI diet with a small energy restriction. The primary outcome measure was weight change at 18 mo. Secondary outcomes included hunger and fasting insulin and lipids. RESULTS: Despite requiring a run-in and the use of multiple incentives, only 60% of the subjects completed the study. The difference in glycemic index between the diets was approximately 35-40 units (40 compared with 79) during all 18 mo of follow-up, and the carbohydrate intake from energy remained at approximately 60% in both groups. The LGI group had a slightly greater weight loss in the first 2 mo of follow-up (-0.72 compared with -0.31 kg), but after 12 mo of follow-up both groups began to regain weight. After 18 mo, the weight change was not significantly different (P = 0.93) between groups (LGI: -0.41 kg; HGI: -0.26 kg). A greater reduction was observed in the LGI diet group for triacylglycerol (difference = -16.4 mg/dL; P = 0.11) and VLDL cholesterol (difference = -3.7 mg/dL; P = 0.03). CONCLUSIONS: Long-term weight changes were not significantly different between the HGI and LGI diet groups; therefore, this study does not support a benefit of an LGI diet for weight control. Favorable changes in lipids confirmed previous results.

Protective action of a hydroalcoholic extract of a vinifera grape skin on experimental preeclampsia in rats.

OBJECTIVE: This study was designed to determine the protective effects of a vinifera grape skins extract (GSE, 200 mg/kg/day) on the deleterious effect observed in experimental preeclampsia, a condition where reduced nitric oxide production and increase in oxidative stress are present. METHODS: A condition similar to preeclampsia was induced by chronic inhibition of nitric oxide synthesis by L-NAME (60 mg/kg/day, orally) in pregnant rats. Blood pressure (systolic, mean and diastolic) was measured with the tail cuff method on day 20 of pregnant control rats; pregnant rats treated with L-NAME, L-NAME plus GSE or GSE from day 13 to day 20 of pregnancy. Glucose was infused in anesthetized pregnant rats at day 20 and blood glucose and insulin were estimated at time zero, 15, 30, 45 and 60 minutes after beginning of glucose infusion. The number of fetus alive was also estimated at day 20 of pregnancy. In parallel, blood pressure was measured in non-pregnant and in non-pregnant rats treated with L-NAME during 7 days. RESULTS: Increase in arterial pressure, reduction of alive fetus at the end of pregnancy and increase in insulin resistance was observed in pregnant L-NAME rats but not in pregnant L-NAME plus GSE rats or in pregnant GSE rats. Increase in arterial pressure was also observed in non-pregnant L-NAME rats. CONCLUSION: The present study demonstrated a protective effect of GSE in experimental preeclampsia since the deleterious effect induced by L-NAME that is, increased in stillbirth, hypertension and insulin resistance were significantly reduced by oral treatment with the extract. Probably an endothelium-dependent vasodilator effect and an antioxidant action play an important role on the effects of GSE in experimental preeclampsia.

Osteopontin expression in coculture of differentiating rat fetal skeletal fibroblasts and myoblasts.

Skeletal fibroblasts in vitro can acquire myofibroblast phenotypes by the development of biochemical and morphological features, mainly the expression of alpha-smooth-muscle actin (alpha-SMA). Myogenic differentiation is a central event in skeletal muscle development, and has commonly been studied in vitro in the context of skeletal muscle development and regeneration. Controlling this process is a complex set of interactions between myoblasts and the extracellular matrix. Osteopontin (OPN) is an acidic, phosphorylated matrix protein that contains an Arg-Gly-Asp (RGD) cell attachment sequence and has been identified as an adhesive and migratory substrate for several cell types. The aim of this study was to investigate osteopontin expression during the differentiation of skeletal fibroblasts into myofibroblasts and during myogenesis in a coculture model. Fibroblasts and myoblasts were obtained from skeletal muscle of 18-d-old Wistar strain rat fetuses by enzymatic dissociation. At 1 and 9 d, cocultures were immunolabeled, and the cells were also separately subjected to Western blotting to analyze OPN expression. Our data using confocal microscopy showed that myoblasts displayed a strong staining for OPN and that this labeling was maintained after myotube differentiation. Conversely, during fibroblast differentiation into myofibroblasts, we observed a significant increase in OPN expression. The results obtained by immunolabeling were confirmed by Western blotting. We suggest that OPN is important mainly during early stages of myogenesis, facilitating myoblast fusion and differentiation, and that the increased expression of OPN in myofibroblasts might be related to its effects as a key cytokine regulating tissue repair and inflammation.

Association between nutrition and gender during lactation influencing glucose homeostasis and blood pressure of the adult offspring.

The aim of this study was to evaluate the hypothesis that the association between nutritional status and gender of rat pups during the early postnatal period (lactation) induces changes in glucose homeostasis and blood pressure of the pups when becoming adults. The results indicate that undernourishment during lactation is associated with gender and affects glucose homeostasis and blood pressure of female adults. In our experiments, the blood glucose level at the end of a clamping was significantly different in the undernourished females (FU) compared with the female controls (FC) (FC: 11.2 +/- 0.9 mmol/l; FU: 26.9 +/- 2.1 mmol/l; p

Norbixin ingestion did not induce any detectable DNA breakage in liver and kidney but caused a considerable impairment in plasma glucose levels of rats and mice.

From the seeds of Bixa orellana are extracted the carotenoids bixin and norbixin that have been widely used for coloring food. In this study, the toxicity of norbixin, purified or not (annatto extract containing 50% norbixin), was investigated in mice and rats after 21 days of ingestion through drinking water. Mice were exposed to doses of 56 and 351 mg/kg (annatto extract) and 0.8, 7.6, 66 and 274 mg/kg (norbixin). Rats were exposed to doses of 0.8, 7.5 and 68 mg/kg (annatto extract) and 0.8, 8.5 and 74 mg/kg (norbixin). In rats, no toxicity was detected by plasma chemistry. In mice, norbixin induced an increase in plasma alanine aminotransferase activity (ALT) while both norbixin and annatto extract induced a decrease in plasma total protein and globulins (P < 0.05). However, no signs of toxicity were detected in liver by histopathological analysis. No enhancement in DNA breakage was detected in liver or kidney from mice treated with annatto pigments, as evaluated by the comet assay. Nevertheless, there was a remarkable effect of norbixin on the glycemia of both rodent species. In rats, norbixin induced hyperglycemia that ranged from 26.9% (8.5 mg/kg norbixin, to 52.6% (74 mg/kg norbixin, P < 0.01) above control levels. In mice, norbixin induced hypoglycemia that ranged from 14.4% (0.8 mg/kg norbixin, P < 0.05) to 21.5% (66 mg/kg norbixin, P < 0.001) below control levels. Rats and mice treated with annatto pigments showed hyperinsulinemia and hypoinsulinemia, respectively indicating that pancreatic beta-cells were functional. More studies should be performed to fully understand of how species-related differences influences the biological fate of norbixin.

Efeitos da desnutriçäo protéica durante os períodos pré e pós natal no desenvolvimento cerebelar / Effects of protein undernutrition during the pre and post natal period of the cerebellum development

Estudou-se os efeitos da desnutriçao protéica nao severa, durante os períodos pré e pós natal, no desenvolvimento das camadas corticais cerebelares. Observou-se que a desnutriçao protéica afeta o processo de migraçao celular da camada granular externa, bem como induz atraso na formaçao da camada molecular. Após 60 dias ocorreu recuperaçao histológica do cerebelo em todos animais experimentais.

Estado nutricional de crianças e relaçoes de trabalho da família em uma comunidade rural do Paraná, Brasil / Nutritional status of children and occupational categories of the family in a rural community of Paraná, Brazil

Estudo do estado nutricional de crianças menores de 11 anos moradoras na área rural de Mandaguaçu, Paraná, segundo as relaçoes de trabalho da família, no período de 1972 a 1983. As relaçoes de trabalho foram classificadas em bóia-fria durante todo o período; passagem de trabalhador rural nao-assalariado, meeiros ou arrendatários, para bóia-fria; nunca bóia-fria, e passagem de trabalhador assalariado urbano para bóia-fria. Outras variáveis independentes incluídas na análise foram idade, sexo, instruçao e idade da mae, internaçoes da criança, local de ocorrência do parto, número de filhos vivos, peso ao nascer e condiçao de frequência à escola, para crianças maiores de 5 anos. A análise multivariada através de regressao logística mostra que a desnutriçao aguda foi mais frequente entre as crianças de famílias que passaram de assalariados urbanos para bóias-frias. Comparadas com os filhos de bóias-frias durante todo o período, apresentaram odds ratio de desnutriçao aguda de 2,7 com intervalo de confiança de 95//igual a 1,3-5,7. A desnutriçao aguda associa-se também, e de forma independente, com o número de filhos vivos (p<0,05). A desnutriçao crônica associa-se com a relaçao de trabalho (sendo menos frequente entre as crianças de famílias que passaram de assalariados urbanos para bóias-frias) e com o número de filhos vivos (p<0,05). A prevalência de desnutriçao aguda foi significamente maior entre famílias com menor número de filhos vivos, enquanto para a desnutriçao crônica esta associaçao foi em direçao oposta. Concluiu pela existência de diferentes determinantes para a desnutriçao aguda e para a desnutriçao crônica