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1.
Exp Gerontol ; 173: 112114, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36738979

RESUMO

BACKGROUND: Dietary sodium is a well-known risk factor for cardiovascular and renal disease; however, direct evidence of the longitudinal changes that occur with aging, and the influence of dietary sodium on the age-associated alterations are scarce. METHODS: C57BL/6 mice were maintained for 13 months on a low (LS, 0.02 % Na+), normal (NS, 0.3 % Na+) or high (HS, 1.6 % Na+) salt diet. We assessed 1) the longitudinal trajectories for two markers of cardiovascular and renal dysfunction (blood pressure (BP) and albuminuria), as well as hormonal changes, and 2) end-of-study cardiac and renal parameters. RESULTS: The effect of aging on BP and kidney damage did not reach significance levels in the LS group; however, relative to baseline, there were significant increases in these parameters for animals maintained on NS and HS diets, starting as early as month 7 and month 5, respectively. Furthermore, changes in albuminuria preceded the changes in BP relative to baseline, irrespective of the diet. Circulating aldosterone and plasma renin activity displayed the expected decreasing trends with age and dietary sodium loading. As compared to LS - higher dietary sodium consumption associated with increasing trends in left ventricular mass and volume indices, consistent with an eccentric dilated phenotype. Functional and molecular markers of kidney dysfunction displayed similar trends with increasing long-term sodium levels: higher renovascular resistance, increased glomerular volumes, as well as higher levels of renal angiotensin II type 1 and mineralocorticoid receptors, and lower renal Klotho levels. CONCLUSION: Our study provides a timeline for the development of cardiorenal dysfunction with aging, and documents that increasing dietary salt accelerates the age-induced phenotypes. In addition, we propose albuminuria as a prognostic biomarker for the future development of hypertension. Last, we identified functional and molecular markers of renal dysfunction that associate with long-term dietary salt loading.


Assuntos
Hipertensão , Nefropatias , Sódio na Dieta , Animais , Camundongos , Albuminúria , Pressão Sanguínea , Rim , Camundongos Endogâmicos C57BL , Cloreto de Sódio na Dieta
2.
J Periodontol ; 90(8): 884-893, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30729535

RESUMO

BACKGROUND: Maternal periodontal disease leads to low birth weight (LBW), insulin resistance (IR), increased TNF-α levels, and alterations in insulin signaling in adult offspring. TNF-α has been associated with the stimulation of IKKß/NF-κB, resulting in the decreased expression of GLUT4. Another mechanism that may be involved in decreasing GLUT4 expression is DNA methylation. This study aimed to evaluate in the adult offspring of rats with periodontal disease: IR, inflammatory pathways, DNA methylation, and expression of GLUT4. METHODS: Female Wistar rats were distributed into control and experimental periodontal disease groups. Seven days after induction of periodontal disease, both groups were mated with healthy male rats. After weaning, male offspring were distributed into control offspring (CN-o) and periodontal disease offspring (PED-o) groups. Body weights were measured from 0-75 days of age. At day 75, the following were measured in the offspring: IR (HOMA-IR index); TNF-α and NF-κBp65 content in the gastrocnemius muscle (GM) by western blotting; IKKα/ß, JNK, ERK 1/2, NF-κBp65, and NF-κBp50 phosphorylation status in the GM by western blotting; DNA methylation by restriction digest and real-time PCR(qAMP); and expression of GLUT4 mRNA in the GM by real-time PCR. RESULTS: LBW, IR, increases in TNF-α, IKKα/ß, ERK 1/2, NF-κBp65, and NF-κBp50 decreased expression of GLUT4 mRNA were observed in the PED-o rats. No differences were identified in JNK phosphorylation status and DNA methylation in the evaluated regions of the GLUT4-encoding gene Slc2a4. CONCLUSION: Maternal periodontal disease causes LBW, IR, activation of inflammatory pathways, and decreased GLUT4 expression in the GM of adult offspring.


Assuntos
Resistência à Insulina , Periodontite , Filhos Adultos , Animais , Feminino , Humanos , Insulina , Masculino , Ratos , Ratos Wistar
3.
Sci Rep ; 7(1): 14781, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29093454

RESUMO

Intracellular peptides generated by limited proteolysis are likely to function inside and outside cells and could represent new possibilities for drug development. Here, we used several conformational-sensitive antibodies targeting G-protein coupled receptors to screen for novel pharmacological active peptides. We find that one of these peptides, DITADDEPLT activates cannabinoid type 1 receptors. Single amino acid modifications identified a novel peptide, DIIADDEPLT (Pep19), with slightly better inverse agonist activity at cannabinoid type 1 receptors. Pep19 induced uncoupling protein 1 expression in both white adipose tissue and 3T3-L1 differentiated adipocytes; in the latter, Pep19 activates pERK1/2 and AKT signaling pathways. Uncoupling protein 1 expression induced by Pep19 in 3T3-L1 differentiated adipocytes is blocked by AM251, a cannabinoid type 1 receptors antagonist. Oral administration of Pep19 into diet-induced obese Wistar rats significantly reduces adiposity index, whole body weight, glucose, triacylglycerol, cholesterol and blood pressure, without altering heart rate; changes in the number and size of adipocytes were also observed. Pep19 has no central nervous system effects as suggested by the lack of brain c-Fos expression, cell toxicity, induction of the cannabinoid tetrad, depressive- and anxiety-like behaviors. Therefore, Pep19 has several advantages over previously identified peripherally active cannabinoid compounds, and could have clinical applications.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo Branco/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Obesidade/tratamento farmacológico , Peptídeos , Receptor CB1 de Canabinoide/antagonistas & inibidores , Células 3T3-L1 , Adipócitos/patologia , Tecido Adiposo Branco/patologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Dieta Hiperlipídica/efeitos adversos , Masculino , Camundongos , Obesidade/induzido quimicamente , Obesidade/metabolismo , Obesidade/patologia , Peptídeos/química , Peptídeos/farmacologia , Ratos , Ratos Wistar , Receptor CB1 de Canabinoide/metabolismo
4.
PLoS One ; 12(8): e0183314, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28820906

RESUMO

METHODS: Female Wistar rats were exposed to filtered air (F) or to concentrated fine particulate matter (P) for 15 days. After mating, the rats were divided into four groups and again exposed to F or P (FF, FP, PF, PP) beginning on day 6 of pregnancy. At embryonic day 19, the placenta was collected. The placental structure, the protein and gene expression of TGFß1, VEGF-A, and its receptor Flk-1 and RAS were evaluated by indirect ELISA and quantitative real-time PCR. RESULTS: Exposure to P decreased the placental mass, size, and surface area as well as the TGFß1, VEGF-A and Flk-1 content. In the maternal portion of the placenta, angiotensin II (AngII) and its receptors AT1 (AT1R) and AT2 (AT2R) were decreased in the PF and PP groups. In the fetal portion of the placenta, AngII in the FP, PF and PP groups and AT2R in the PF and PP groups were decreased, but AT1R was increased in the FP group. VEGF-A gene expression was lower in the PP group than in the FF group. CONCLUSIONS: Exposure to pollutants before and/or during pregnancy alters some characteristics of the placenta, indicating a possible impairment of trophoblast invasion and placental angiogenesis with possible consequences for the maternal-fetal interaction, such as a limitation of fetal nutrition and growth.


Assuntos
Exposição Ambiental , Material Particulado/metabolismo , Placenta/anatomia & histologia , Sistema Renina-Angiotensina , Animais , Feminino , Expressão Gênica , Placenta/metabolismo , Gravidez , Ratos , Ratos Wistar
5.
PLoS One ; 12(5): e0177086, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28481921

RESUMO

This study investigated the influence of sodium restriction and antihypertensive drugs on atherogenesis utilizing hypertensive (H) low-density lipoprotein-receptor knockout mice treated or not with losartan (Los) or hydralazine (Hyd) and fed low-sodium (LS) or normal-sodium (NS) chow. Despite reducing the blood pressure (BP) of H-LS mice, the LS diet caused arterial lipid infiltration due to increased plasma total cholesterol (TC) and triglycerides (TG). Los and Hyd reduced the BP of H-LS mice, and Los effectively prevented arterial injury, likely by reducing plasma TG and nonesterified fatty acids. Aortic lipid infiltration was lower in Los-treated H-LS mice (H-LS+Los) than in normotensive (N)-LS and H-LS mice. Aortic angiotensin II type 1 (AT1) receptor content was greater in H-NS than H-LS mice and in H-LS+Hyd than H-LS+Los mice. Carboxymethyl-lysine (CML) and receptor for advanced glycation end products (RAGE) immunostaining was greater in H-LS than H-NS mice. CML and RAGE levels were lower in LS animals treated with antihypertensive drugs, and Hyd enhanced the AT1 receptor level. Hyd also increased the gene expression of F4/80 but not tumor necrosis factor-α, interleukin (IL)-1ß, IL-6, IL-10, intercellular adhesion molecule-1 or cluster of differentiation 66. The novelty of the current study is that in a murine model of simultaneous hypertension and hyperlipidemia, the pleiotropic effect of chronic, severe sodium restriction elicited aortic damage even with reduced BP. These negative effects on the arterial wall were reduced by AT1 receptor antagonism, demonstrating the influence of angiotensin II in atherogenesis induced by a severely LS diet.


Assuntos
Aterosclerose/etiologia , Pressão Sanguínea , Dieta Hipossódica , Hiperlipidemias/complicações , Hipertensão/prevenção & controle , Animais , Hipertensão/complicações , Camundongos , Camundongos Knockout , Receptores de LDL/genética
6.
Clinics (Sao Paulo) ; 72(3): 171-177, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28355363

RESUMO

OBJECTIVE:: To evaluate the respiratory systems of male and female rats maintained in individually ventilated cages (IVCs) from birth until adulthood. METHODS:: Female Wistar rats were housed in individually ventilated cages or conventional cages (CCs) and mated with male Wistar rats. After birth and weaning, the male offspring were separated from the females and kept in cages of the same type until 12 weeks of age. RESULTS:: The level of food consumption was lower in male offspring (IVC=171.7±9; CC=193.1±20) than in female offspring (IVC=100.6±7; CC=123.4±0.4), whereas the water intake was higher in female offspring (IVC=149.8±11; CC=99.2±0) than in male offspring (IVC=302.5±25; CC=249.7±22) at 11 weeks of age when housed in IVCs. The cage temperature was higher in individually ventilated cages than in conventional cages for both male (IVCs=25.9±0.5; CCs=22.95±0.3) and female (IVCs=26.2±0.3; CCs=23.1±0.3) offspring. The respiratory resistance (IVC=68.8±2.8; CC=50.6±3.0) and elastance (IVC=42.0±3.9; CC=32.4±2.0) at 300 µm/kg were higher in the female offspring housed in ventilated cages. The ciliary beat values were lower in both the male (IVCs=13.4±0.2; CC=15±0.4) and female (IVC=13.5±0.4; CC=15.9±0.6) offspring housed in individually ventilated cages than in those housed in conventional cages. The total cell (IVC=117.5±9.7; CC=285.0±22.8), neutrophil (IVC=13.1±4.8; CC=75.6±4.1) and macrophage (IVC=95.2±11.8; CC=170.0±18.8) counts in the bronchoalveolar lavage fluid were lower in the female offspring housed in individually ventilated cages than in those housed in conventional cages. CONCLUSIONS:: The environmental conditions that exist in individually ventilated cages should be considered when interpreting the results of studies involving laboratory animals. In this study, we observed gender dimorphism in both the water consumption and respiratory mechanics of rats kept in ventilated cages.


Assuntos
Abrigo para Animais/normas , Modelos Animais , Fenômenos Fisiológicos Respiratórios , Ventilação , Fatores Etários , Bem-Estar do Animal , Animais , Pressão Sanguínea/fisiologia , Líquido da Lavagem Broncoalveolar , Ingestão de Alimentos/fisiologia , Planejamento Ambiental , Feminino , Frequência Cardíaca/fisiologia , Masculino , Ratos Wistar , Testes de Função Respiratória , Fatores Sexuais , Temperatura , Fatores de Tempo
7.
Clinics ; 72(3): 171-177, Mar. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-840050

RESUMO

OBJECTIVE: To evaluate the respiratory systems of male and female rats maintained in individually ventilated cages (IVCs) from birth until adulthood. METHODS: Female Wistar rats were housed in individually ventilated cages or conventional cages (CCs) and mated with male Wistar rats. After birth and weaning, the male offspring were separated from the females and kept in cages of the same type until 12 weeks of age. RESULTS: The level of food consumption was lower in male offspring (IVC=171.7±9; CC=193.1±20) than in female offspring (IVC=100.6±7; CC=123.4±0.4), whereas the water intake was higher in female offspring (IVC=149.8±11; CC=99.2±0) than in male offspring (IVC=302.5±25; CC=249.7±22) at 11 weeks of age when housed in IVCs. The cage temperature was higher in individually ventilated cages than in conventional cages for both male (IVCs=25.9±0.5; CCs=22.95±0.3) and female (IVCs=26.2±0.3; CCs=23.1±0.3) offspring. The respiratory resistance (IVC=68.8±2.8; CC=50.6±3.0) and elastance (IVC=42.0±3.9; CC=32.4±2.0) at 300 µm/kg were higher in the female offspring housed in ventilated cages. The ciliary beat values were lower in both the male (IVCs=13.4±0.2; CC=15±0.4) and female (IVC=13.5±0.4; CC=15.9±0.6) offspring housed in individually ventilated cages than in those housed in conventional cages. The total cell (IVC=117.5±9.7; CC=285.0±22.8), neutrophil (IVC=13.1±4.8; CC=75.6±4.1) and macrophage (IVC=95.2±11.8; CC=170.0±18.8) counts in the bronchoalveolar lavage fluid were lower in the female offspring housed in individually ventilated cages than in those housed in conventional cages. CONCLUSIONS: The environmental conditions that exist in individually ventilated cages should be considered when interpreting the results of studies involving laboratory animals. In this study, we observed gender dimorphism in both the water consumption and respiratory mechanics of rats kept in ventilated cages.


Assuntos
Animais , Masculino , Feminino , Abrigo para Animais/normas , Modelos Animais , Fenômenos Fisiológicos Respiratórios , Ventilação , Fatores Etários , Bem-Estar do Animal , Pressão Sanguínea/fisiologia , Líquido da Lavagem Broncoalveolar , Ingestão de Alimentos/fisiologia , Planejamento Ambiental , Frequência Cardíaca/fisiologia , Ratos Wistar , Testes de Função Respiratória , Fatores Sexuais , Temperatura , Fatores de Tempo
8.
PLoS One ; 11(8): e0161598, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27560182

RESUMO

INTRODUCTION: Previous studies from our laboratory demonstrated that dietary salt overload and salt restriction during pregnancy were associated with cardiac and renal structural and/or functional alterations in adult offspring. The present study evaluated renal and cardiac structure and the local renin-angiotensin system in newborns from dams fed high-, normal- or low-salt diets during pregnancy. METHODS: Female Wistar rats were fed low- (LS, 0.15% NaCl), normal- (NS, 1.3% NaCl) or high- (HS, 8% NaCl) salt diets during pregnancy. Kidneys and hearts were collected from newborns (n = 6-8/group) during the first 24 hours after birth to evaluate possible changes in structure using stereology. Protein expression of renin-angiotensin system components was evaluated using an indirect enzyme-linked immunosorbent assay (ELISA). RESULTS: No differences between groups were observed in total renal volume, volume of renal compartments or number of glomeruli. The transverse diameter of the nuclei of cardiomyocytes was greater in HS than NS males in the left and right ventricles. Protein expression of the AT1 receptor was lower in the kidneys of the LS than in those of the NS and HS males but not females. Protein expression of the AT2 receptor was lower in the kidneys of the LS males and females than in those of the NS males and females. CONCLUSION: High salt intake during pregnancy induced left and right ventricular hypertrophy in male newborns. Salt restriction during pregnancy reduced the expression of renal angiotensin II receptors in newborns.


Assuntos
Coração/anatomia & histologia , Rim/anatomia & histologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Cloreto de Sódio na Dieta/administração & dosagem , Cloreto de Sódio/química , Animais , Animais Recém-Nascidos , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal , Dieta Hipossódica , Ensaio de Imunoadsorção Enzimática , Feminino , Hipertrofia Ventricular Direita , Miócitos Cardíacos/metabolismo , Gravidez , Prenhez , Ratos , Ratos Wistar , Renina/metabolismo
9.
Physiol Behav ; 154: 68-75, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26596702

RESUMO

A low-salt (LS) diet during pregnancy has been linked to insulin resistance in adult offspring, at least in the experimental setting. However, it remains unclear if this effect is due to salt restriction during early or late pregnancy. To better understand this phenomenon, 12-week-old female Wistar rats were fed a LS or normal-salt (NS) diet during gestation or a LS diet during either the first (LS10) or second (LS20) half of gestation. Glucose tolerance test, HOMA-IR, gene expression analysis and DNA methylation measurements were conducted for the Insr, Igf1, Igf1r, Ins1 and Ins2 genes in the livers of neonates and in the liver, white adipose tissue and muscle of 20-week-old male offspring. Birth weight was lower in the LS20 and LS animals compared with the NS and LS10 rats. In the liver, the Igf1 levels in the LS10, LS20 and LS neonates were lower than those in the NS neonates. Methylation of the Insr, Igf1r, Ins1 and Ins2 genes was influenced in a variable manner by low salt intake during pregnancy. Increased liver Igf1 methylation was observed in the LS and LS20 neonates compared with their NS and LS10 counterparts. Glucose intolerance was observed in adult offspring as an effect of low salt intake over the duration of pregnancy. Compared to the NS animals, the HOMA-IR was higher in the 12-week-old LS and 20-week-old LS-10 rats. Based on these results, it appears that the reason a LS diet during pregnancy induces a low birth weight is its negative correlation with Igf1 DNA methylation in neonates.


Assuntos
Glicemia/efeitos dos fármacos , Metilação de DNA/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/genética , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Cloreto de Sódio na Dieta/farmacologia , Fatores Etários , Animais , Animais Recém-Nascidos , Metilação de DNA/efeitos dos fármacos , Dieta Hipossódica , Jejum/sangue , Feminino , Teste de Tolerância a Glucose , Recém-Nascido de Baixo Peso , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Gravidez , Ratos , Ratos Wistar , Estatísticas não Paramétricas
10.
Toxicol Lett ; 232(2): 475-80, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25481569

RESUMO

This study aimed to verify the development of placental and systemic inflammation in rats exposed to fine particulate matter before or during pregnancy. Wistar rats were exposed to filtered air (control) or to a load of 600 µg/m(3) of fine particles in the air. The gene expression of IL-1ß, IL-4, IL-6, IL-10, INF-γ, TNF-α and Toll-like receptor 4 in the placenta was evaluated. The serum and placental concentrations of IL-1ß, IL-4, IL-6, IL-10, INF-γ and TNF-α were measured. The total and differential blood leukocyte and blood platelet count was assessed. Compared to control animals, IL-4 content was elevated in the fetal portion of the placenta in rats exposed to air pollution before and during pregnancy. Increased IL-4 suggests that a placental inflammatory reaction may have occurred in response to exposure to fine particulate matter and that this cytokine was responsible, among possibly others factors, for resolution of the inflammatory reaction.


Assuntos
Poluentes Atmosféricos/toxicidade , Feto/metabolismo , Interleucina-4/metabolismo , Material Particulado/toxicidade , Placenta/metabolismo , Animais , Contagem de Células Sanguíneas , Feminino , Feto/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Exposição por Inalação , Tamanho da Partícula , Placenta/efeitos dos fármacos , Gravidez , Ratos , Ratos Wistar
11.
J Nutr ; 144(10): 1571-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25122644

RESUMO

Many studies have shown that risk factors that are independent of blood pressure (BP) can contribute to the development of cardiac hypertrophy (CH). Among these factors, high-salt (HS) intake was prominent. Although some studies have attempted to elucidate the role of salt in the development of this disease, the mechanisms by which salt acts are not yet fully understood. Thus, the aim of this study was to better understand the mechanisms of CH and interstitial fibrosis (IF) caused by HS intake. Male Wistar rats were divided into 5 groups according to diet [normal salt (NS; 1.27% NaCl) or HS (8% NaCl)] and treatment [losartan (LOS) (HS+LOS group), hydralazine (HZ) (HS+HZ group), or N-acetylcysteine (NAC) (HS+NAC group)], which was given in the drinking water. Tail-cuff BP, transverse diameter of the cardiomyocyte, IF, angiotensin II type 1 receptor (AT1) gene and protein expression, serum aldosterone, cardiac angiotensin II, cardiac thiobarbituric acid-reactive substances, and binding of conformation-specific anti-AT1 and anti-angiotensin II type 2 receptor (AT2) antibodies in the 2 ventricles were measured. Based on the left ventricle transverse diameter data, the primary finding was the occurrence of significant BP-independent CH in the HS+HZ group (96% of the HS group) and a partial or total prevention of such hypertrophy via treatment with NAC or LOS (81% and 67% of the HS group, respectively). The significant total or partial prevention of IF using all 3 treatments (HS+HZ, 27%; HS+LOS, 27%; and HS+NAC, 58% of the HS group, respectively), and an increase in the AT1 gene and protein expression and activity in groups that developed CH, confirmed that CH occurred via the AT1 in this experimental model. Thus, this study unveiled some relevant previously unknown mechanisms of CH induced by chronic HS intake in Wistar rats. The link of oxidative stress with CH in our experimental model is very interesting and stimulates further evaluation for its full comprehension.


Assuntos
Cardiomegalia/patologia , Miócitos Cardíacos/efeitos dos fármacos , Receptor Tipo 1 de Angiotensina/metabolismo , Cloreto de Sódio na Dieta/efeitos adversos , Acetilcisteína/farmacologia , Aldosterona/sangue , Angiotensina II/metabolismo , Animais , Anti-Hipertensivos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal , Cardiomegalia/induzido quimicamente , Cardiomegalia/genética , Frequência Cardíaca , Hematócrito , Hidralazina/farmacologia , Losartan/farmacologia , Masculino , Miócitos Cardíacos/metabolismo , Potássio/sangue , Potássio/urina , Ratos , Ratos Wistar , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 2 de Angiotensina/genética , Receptor Tipo 2 de Angiotensina/metabolismo , Sistema Renina-Angiotensina/efeitos dos fármacos , Sódio/sangue , Sódio/urina , Cloreto de Sódio na Dieta/administração & dosagem , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
12.
Proteomics ; 12(17): 2668-81, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22740317

RESUMO

Intracellular peptides generated by the proteasome and oligopeptidases have been suggested to function in signal transduction and to improve insulin resistance in mice fed a high-caloric diet. The aim of this study was to identify specific intracellular peptides in the adipose tissue of Wistar rats that could be associated with the physiological and therapeutic control of glucose uptake. Using semiquantitative mass spectrometry and LC/MS/MS analyses, we identified ten peptides in the epididymal adipose tissue of the Wistar rats; three of these peptides were present at increased levels in rats that were fed a high-caloric Western diet (WD) compared with rats fed a control diet (CD). The results of affinity chromatography suggested that in the cytoplasm of epididymal adipose tissue from either WD or CD rats, distinctive proteins bind to these peptides. However, despite the observed increase in the WD animals, the evaluated peptides increased insulin-stimulated glucose uptake in 3T3-L1 adipocytes treated with palmitate. Thus, intracellular peptides from the adipose tissue of Wistar rats can bind to specific proteins and facilitate insulin-induced glucose uptake in 3T3-L1 adipocytes.


Assuntos
Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Glucose/metabolismo , Resistência à Insulina , Peptídeos/análise , Peptídeos/metabolismo , Células 3T3 , Adipócitos/citologia , Adipócitos/metabolismo , Sequência de Aminoácidos , Animais , Cromatografia de Afinidade , Cromatografia Líquida , Ingestão de Energia , Insulina/metabolismo , Masculino , Camundongos , Dados de Sequência Molecular , Ácido Palmítico/metabolismo , Ligação Proteica , Proteínas/metabolismo , Ratos , Ratos Wistar , Espectrometria de Massas em Tandem
13.
Clinics (Sao Paulo) ; 67(3): 255-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22473407

RESUMO

OBJECTIVE: The preservation of biological samples at a low temperature is important for later biochemical and/or histological analyses. However, the molecular viability of thawed samples has not been studied sufficiently in depth. The present study was undertaken to evaluate the viability of intact tissues, tissue homogenates, and isolated total RNA after defrosting for more than twenty-four hours. METHODS: The molecular viability of the thawed samples (n = 82) was assessed using the A260/A280 ratio, the RNA concentration, the RNA integrity, the level of intact mRNA determined by reverse transcriptase polymerase chain reaction, the protein level determined by Western blotting, and an examination of the histological structure. RESULTS: The integrity of the total RNA was not preserved in the thawed intact tissue, but the RNA integrity and level of mRNA were perfectly preserved in isolated defrosted samples of total RNA. Additionally, the level of ß-actin protein was preserved in both thawed intact tissue and homogenates. CONCLUSION: Isolated total RNA does not undergo degradation due to thawing for at least 24 hours, and it is recommended to isolate the total RNA as soon as possible after tissue collection. Moreover, the protein level is preserved in defrosted tissues.


Assuntos
Criopreservação/métodos , Perfilação da Expressão Gênica/métodos , Estabilidade de RNA/genética , RNA/genética , Manejo de Espécimes/métodos , Actinas/análise , Animais , Masculino , Modelos Animais , RNA/química , RNA/isolamento & purificação , Estabilidade de RNA/fisiologia , Distribuição Aleatória , Ratos , Fatores de Tempo
14.
Life Sci ; 90(19-20): 785-92, 2012 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-22521760

RESUMO

AIMS: The goal of the current study was to evaluate the impact of maternal sodium intake during gestation on the systemic and renal renin-angiotensin-aldosterone-system (RAAS) of the adult offspring. MAIN METHODS: Female Wistar rats were fed high- (HSD-8.0% NaCl) or normal-sodium diets (NSD-1.3% NaCl) from 8 weeks of age until the delivery of their first litter. After birth, the offspring received NSD. Tail-cuff blood pressure (TcBP) was measured in the offspring between 6 and 12 weeks of age. At 12 weeks of age, the offspring were subjected to either one week of HSD or low sodium diet (LSD-0.16% NaCl) feeding to evaluate RAAS responsiveness or to acute saline overload to examine sodium excretory function. Plasma (PRA) and renal renin content (RRC), serum aldosterone (ALDO) levels, and renal cortical and medullary renin mRNA expression levels were evaluated at the end of the study. KEY FINDINGS: TcBP was higher among dams fed HSD, but no TcBP differences were observed among the offspring. Male offspring, however, exhibited increased TcBP after one week of HSD feeding, and this effect was independent of maternal diet. Increased RAAS responsiveness to the HSD and LSD was also observed in male offspring. The baseline levels of PRA, ALDO, and cortical and medullary renin gene expression were lower but the RRC levels were higher among HSD-fed male offspring (HSDoff). Conversely, female HSDoff showed reduced sodium excretion 4 h after saline overload compared with female NSDoff. SIGNIFICANCE: High maternal sodium intake is associated with gender-specific changes in RAAS responsiveness among adult offspring.


Assuntos
Efeitos Tardios da Exposição Pré-Natal , Sistema Renina-Angiotensina/efeitos dos fármacos , Sódio na Dieta/farmacologia , Envelhecimento/fisiologia , Aldosterona/sangue , Animais , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Dieta , Feminino , Hematócrito , Rim/efeitos dos fármacos , Rim/metabolismo , Córtex Renal/metabolismo , Medula Renal/metabolismo , Masculino , Reação em Cadeia da Polimerase , Gravidez , RNA Mensageiro/biossíntese , Ratos , Renina/biossíntese , Renina/metabolismo , Caracteres Sexuais , Sódio/sangue , Sódio/urina
15.
Clinics ; 67(3): 255-259, 2012. ilus, graf
Artigo em Inglês | LILACS | ID: lil-623100

RESUMO

OBJECTIVE: The preservation of biological samples at a low temperature is important for later biochemical and/or histological analyses. However, the molecular viability of thawed samples has not been studied sufficiently in depth. The present study was undertaken to evaluate the viability of intact tissues, tissue homogenates, and isolated total RNA after defrosting for more than twenty-four hours. METHODS: The molecular viability of the thawed samples (n = 82) was assessed using the A260/A280 ratio, the RNA concentration, the RNA integrity, the level of intact mRNA determined by reverse transcriptase polymerase chain reaction, the protein level determined by Western blotting, and an examination of the histological structure. RESULTS: The integrity of the total RNA was not preserved in the thawed intact tissue, but the RNA integrity and level of mRNA were perfectly preserved in isolated defrosted samples of total RNA. Additionally, the level of β-actin protein was preserved in both thawed intact tissue and homogenates. CONCLUSION: Isolated total RNA does not undergo degradation due to thawing for at least 24 hours, and it is recommended to isolate the total RNA as soon as possible after tissue collection. Moreover, the protein level is preserved in defrosted tissues.


Assuntos
Animais , Masculino , Ratos , Criopreservação/métodos , Perfilação da Expressão Gênica/métodos , RNA , Estabilidade de RNA/genética , Manejo de Espécimes/métodos , Actinas/análise , Modelos Animais , Distribuição Aleatória , RNA , Estabilidade de RNA/fisiologia , Fatores de Tempo
16.
J Nutr ; 140(10): 1742-51, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20724490

RESUMO

High salt intake is a known cardiovascular risk factor and is associated with cardiac alterations. To better understand this effect, male Wistar rats were fed a normal (NSD: 1.3% NaCl), high 4 (HSD4: 4%), or high 8 (HSD8: 8%) salt diet from weaning until 18 wk of age. The HSD8 group was subdivided into HSD8, HSD8+HZ (15 mg . kg(-1) . d(-1) hydralazine in the drinking water), and HSD8+LOS (20 mg . kg(-1) . d(-1) losartan in the drinking water) groups. The cardiomyocyte diameter was greater in the HSD4 and HSD8 groups than in the HSD8+LOS and NSD groups. Interstitial fibrosis was greater in the HSD4 and HSD8 groups than in the HSD8+HZ and NSD groups. Hydralazine prevented high blood pressure (BP) and fibrosis, but not cardiomyocyte hypertrophy. Losartan prevented high BP and cardiomyocyte hypertrophy, but not fibrosis. Angiotensin II type 1 receptor (AT(1)) protein expression in both ventricles was greater in the HSD8 group than in the NSD group. Losartan, but not hydralazine, prevented this effect. Compared with the NSD group, the binding of an AT(1) conformation-specific antibody that recognizes the activated form of the receptor was lower in both ventricles in all other groups. Losartan further lowered the binding of the anti-AT(1) antibody in both ventricles compared with all other experimental groups. Angiotensin II was greater in both ventricles in all groups compared with the NSD group. Myocardial structural alterations in response to HSD are independent of the effect on BP. Salt-induced cardiomyocyte hypertrophy and interstitial fibrosis possibly are due to different mechanisms. Evidence from the present study suggests that salt-induced AT(1) receptor internalization is probably due to angiotensin II binding.


Assuntos
Pressão Sanguínea/fisiologia , Cardiomegalia/induzido quimicamente , Cardiomegalia/fisiopatologia , Miocárdio/patologia , Cloreto de Sódio na Dieta/administração & dosagem , Aldosterona/sangue , Angiotensina II/análise , Bloqueadores do Receptor Tipo 1 de Angiotensina II/administração & dosagem , Animais , Anti-Hipertensivos/administração & dosagem , Cardiomegalia/patologia , Colágeno Tipo I/análise , Colágeno Tipo III/análise , Modelos Animais de Doenças , Ingestão de Líquidos , Ingestão de Alimentos , Ecocardiografia , Fibrose , Expressão Gênica , Ventrículos do Coração/química , Ventrículos do Coração/patologia , Hidralazina/administração & dosagem , Hipertensão/fisiopatologia , Hipertensão/prevenção & controle , Losartan/administração & dosagem , Masculino , Potássio/sangue , Ratos , Ratos Wistar , Receptor Tipo 1 de Angiotensina/análise , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/fisiologia , Receptor Tipo 2 de Angiotensina/análise , Renina/sangue , Sistema Renina-Angiotensina/genética , Sistema Renina-Angiotensina/fisiologia , Sódio/sangue , Sódio/urina , Fator de Crescimento Transformador beta/análise , Urina
17.
Braz. j. pharm. sci ; 46(2): 353-362, Apr.-June 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-564903

RESUMO

This study was carried out in the outpatient unit of the Teaching Hospital of the University of São Paulo (USP), and studied the impact of an educational program aimed at improving hypertensive patients' compliance to treatment. Seventy five (75) hypertensive patients of both sexes took part in the study which had no age or race discrimination. Participants presented no other concomitant pathology, except obesity, diabetes and dyslipidemia. Forty one patients were allocated to an experimental group (EG). Experimental patients attended lectures on the use of medication and artery hypertension (AH) and received personal pharmaceutical guidance for nine months. The control group (CG) comprised 34 patients who did not attend lectures or receive pharmaceutical advice in this period. The results were assessed by means of serum levels of cholesterol and fractions of tryacylglicerol (TG), urine sodium and potassium, arterial pressure (AP), body mass index (BMI), waist-hip ratio (WHR), and also based on responses to a questionnaire focusing on AH and treatment. Patients who received the guidance showed a greater decrease in AP, TG and WHR, besides an increase of potassium excretion through urine. The experimental group also scored higher on the questionnaires compared to the CG. It was concluded that the educational process, applied under the conditions of the present study, improves clients' clinical response to antihypertensive treatment and should be included in therapeutic strategies of health care services dealing with hypertensive patients.


Este trabalho, realizado no ambulatório do Hospital Universitário da USP, estudou a repercussão de um programa educacional visando melhorar a adesão do paciente hipertenso ao tratamento. Participaram do trabalho 75 pacientes de ambos os sexos, sem discriminação de idade ou raça, sem outras patologias concomitantes, exceto obesidade, diabetes e dislipidemia. Quarenta e um pacientes assistiram palestras sobre uso de medicamentos e hipertensão arterial (HA), receberam orientação farmacêutica individualizada durante nove meses e foram denominados grupo experimental (GE); o grupo controle (GC), composto por 34 pacientes não assistiu palestras nem recebeu orientação farmacêutica, neste período. Os resultados foram avaliados por meio de níveis séricos de colesterol e frações, triacil-gliceróis (TG), sódio e potássio urinários, pressão arterial (PA), índice de massa corpórea (IMC), relação cintura/quadril (RCQ), além de respostas a questionário enfocando HA e tratamento. Verificou-se que os pacientes orientados apresentaram maior decréscimo da PA, TG e da RCQ, além de aumento da excreção urinária de potássio e do percentual de acertos em questionários, em relação ao GC. Concluiu-se que o processo educativo, utilizado nas condições deste estudo, melhora a resposta clínica do paciente ao tratamento anti-hipertensivo e deve fazer parte das estratégias terapêuticas de serviços de atendimento a pacientes hipertensos.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Hospitais Universitários , Hipertensão , Adesão à Medicação , Monitorização Ambulatorial , Assistência Farmacêutica , Educação em Saúde , Hiperglicemia , Obesidade
18.
Regul Pept ; 162(1-3): 61-7, 2010 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-20346375

RESUMO

Sucrose-fed rats, a model of metabolic syndrome, are characterized by insulin resistance, obesity, hypertension, and high plasma levels of triacylglycerols and angiotensin II (Ang II). However, whether tissue renin-angiotensin system (RAS) is altered in metabolic syndrome is unclear. To study this issue, food ad libitum and water (C) or 20% sucrose solution (SC) were given to adult male Wistar rats, for 30 days. Body weight (BW), blood pressure (BP), epididymal adipose tissue (EPI) mass, rate of in vivo fatty acid (FA) synthesis in EPI, circulating glucose, insulin, leptin, angiotensins I and II, triacylglycerols, and plasma renin (PRA) and angiotensin-converting enzyme (ACE) activities were evaluated. In kidneys and EPI, gene and protein expression of type 1 (AT(1)) and 2 (AT(2)) Ang II receptors, ACE, angiotensinogen (AGT) as well as protein expression of angiotensin-converting enzyme 2 (ACE2) were determined. In both tissues, Ang I, Ang II and Ang-(1-7) contents were also measured by HPLC. In SC rats higher BP, EPI mass, circulating triacylglycerols, insulin, leptin, PRA and, Ang II were found. In EPI, the rate of in vivo FA synthesis was associated with increased Ang-(1-7), protein expression of AT(1) and AT(2) receptors, ACE2, AGT, and gene expression of AGT although a reduction in ACE activity and in adipose Ang I and Ang II contents was observed. In kidneys, AT(1) and AT(2), ACE and AGT gene and protein expression as well as protein expression of ACE2 were unaltered while Ang II, Ang-(1-7) and ACE activity increased. These RAS component changes seem to be tissue specific and possibly are related to enhancement of FA synthesis, EPI mass and hypertension.


Assuntos
Tecido Adiposo/metabolismo , Angiotensina I/metabolismo , Fragmentos de Peptídeos/metabolismo , Peptidil Dipeptidase A/metabolismo , Sacarose/administração & dosagem , Tecido Adiposo/enzimologia , Enzima de Conversão de Angiotensina 2 , Animais , Sequência de Bases , Glicemia/análise , Western Blotting , Cromatografia Líquida de Alta Pressão , Primers do DNA , Masculino , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Physiol Behav ; 95(1-2): 145-51, 2008 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-18572207

RESUMO

A number of studies conducted in humans and in animals have observed that events occurring early in life are associated with the development of diseases in adulthood. Salt overload and restriction during pregnancy and lactation are responsible for functional (hemodynamic and hormonal) and structural alterations in adult offspring. Our group observed that lower birth weight and insulin resistance in adulthood is associated with salt restriction during pregnancy. On the other hand, perinatal salt overload is associated with higher blood pressure and higher renal angiotensin II content in adult offspring. Therefore, we hypothesised that renin-angiotensin system (RAS) function is altered by changes in sodium intake during pregnancy. Such changes may influence fetoplacental blood flow and thereby fetal nutrient supply, with effects on growth in utero and, consequently, on birth weight. Female Wistar rats were fed low-salt (LS), normal-salt (NS), or high-salt (HS) diet, starting before conception and continuing until day 19 of pregnancy. Blood pressure, heart rate, fetuses and dams' body weight, placentae weight and litter size were measured on day 19 of pregnancy. Cardiac output, uterine and placental blood flow were also determined on day 19. Expressions of renin-angiotensin system components and of the TNF-alpha gene were evaluated in the placentae. Plasma renin activity (PRA) and plasma and tissue angiotensin-converting enzyme (ACE) activity, as well as plasma and placental levels of angiotensins I, II, and 1-7 were measured. Body weight and kidney mass were greater in HS than in NS and LS dams. Food intake did not differ among the maternal groups. Placental weight was lower in LS dams than in NS and HS dams. Fetal weight was lower in the LS group than in the NS and HS groups. The PRA was greater in LS dams than in NS and HS dams, although ACE activity (serum, cardiac, renal, and placental) was unaffected by the level of sodium intake. Placental levels of angiotensins I and II were lower in the HS group than in the NS and LS groups. Placental angiotensin receptor type 1 (AT(1)) gene expression and levels of thiobarbituric acid reactive substances (TBARS) were higher in HS dams, as were uterine blood flow and cardiac output. The degree of salt intake did not influence plasma sodium, potassium or creatinine. Although fractional sodium excretion was higher in HS dams than in NS and LS dams, fractional potassium excretion was unchanged. In conclusion, findings from this study indicate that the reduction in fetal weight in response to salt restriction during pregnancy does not involve alterations in uterine-placental perfusion or the RAS. Moreover, no change in fetal weight is observed in response to salt overload during pregnancy. However, salt overload did lead to an increase in placental weight and uterine blood flow associated with alterations in maternal plasma and placental RAS. Therefore, these findings indicate that changes in salt intake during pregnancy lead to alterations in uterine-placental perfusion and fetal growth.


Assuntos
Circulação Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Placenta/metabolismo , Efeitos Tardios da Exposição Pré-Natal , Sistema Renina-Angiotensina/efeitos dos fármacos , Cloreto de Sódio na Dieta/farmacologia , Útero/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Pressão Sanguínea/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Peptidil Dipeptidase A/metabolismo , Placenta/irrigação sanguínea , Placenta/efeitos dos fármacos , Gravidez , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Útero/metabolismo
20.
Life Sci ; 82(13-14): 728-32, 2008 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-18289603

RESUMO

Low birth weight has been associated with increased obesity in adulthood. It has been shown that dietary salt restriction during intrauterine life induces low birth weight and insulin resistance in adult Wistar rats. The present study had a two-fold objective: to evaluate the effects that low salt intake during pregnancy and lactation has on the amount and distribution of adipose tissue; and to determine whether the phenotypic changes in fat mass in this model are associated with alterations in the activity of the renin-angiotensin system. Maternal salt restriction was found to reduce birth weight in male and female offspring. In adulthood, the female offspring of dams fed the low-salt diet presented higher adiposity indices than those seen in the offspring of dams fed a normal-salt diet. This was attributed to the fact that adipose tissue mass (retroperitoneal but not gonadal, mesenteric or inguinal) was greater in those rats than in the offspring of dams fed a normal diet. The adult offspring of dams fed the low-salt diet, compared to those dams fed a normal-salt diet, presented the following: plasma leptin levels higher in males and lower in females; plasma renin activity higher in males but not in females; and no differences in body weight, mean arterial blood pressure or serum angiotensin-converting enzyme activity. Therefore, low salt intake during pregnancy might lead to the programming of obesity in adult female offspring.


Assuntos
Adiposidade/fisiologia , Dieta Hipossódica/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/etiologia , Tecido Adiposo/crescimento & desenvolvimento , Animais , Pressão Sanguínea/fisiologia , Feminino , Leptina/sangue , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/enzimologia , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Ratos , Ratos Wistar , Renina/sangue , Renina/metabolismo , Sistema Renina-Angiotensina/fisiologia , Fatores Sexuais , Cloreto de Sódio na Dieta/administração & dosagem
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