Total plasmatic homocysteine and von Willebrand factor in experimental diabetes mellitus

OBJECTIVES: To determine the plasma homocysteine and von Willebrand factor levels as markers of endothelial dysfunction in rats with diabetes mellitus induced by streptozotocin. METHODS: Thirty-five adult male rats (Rattus norvegicus albinus) (weight between 180-200g) were randomized into three groups: control group (n=10), which received no drugs or vehicles; sham group (n=10), which received streptozotocin solution; and diabetic group (n=15), which received streptozotocin. Eight weeks after diabetes mellitus induction, the animals were weighed and anesthesized; blood samples were collected from abdominal aorta for plasma total homocysteine, von Willebrand factor and glucose levels. RESULTS: The experimental model was reproducible in 100% of animals. The mean plasma homocysteine levels were: 7.9 µmol/l (control), 8.6µmol/l (sham) and 6.1µmol/l (diabetic), with difference among the groups (p<0.01). Multiple comparison analysis among the groups showed that values in the diabetic group were lower than in the sham group (p<0.01). The mean von Willebrand factor values were 0.15 U/l (control), 0.16U/l (sham) and 0.18 U/l (diabetic), with difference among the groups (p=0.03). The mean value was higher in the diabetic group than in the control group (p<0.05). Correlation between homocysteine and von Willebrand factor was not observed in the diabetic group. CONCLUSION: Reduced homocysteine levels and increased von Willebrand factor levels were observed in diabetes mellitus induced by streptozotocin; nevertheless, there were no correlations between them and with final glucose levels.OBJETIVOS: Determinar os valores plasmáticos de homocisteína e fator von Willebrand, como marcador de disfunção endotelial, em ratos com diabete melito induzido por estreptozotocina. MÉTODOS: Trinta e cinco ratos (rattus norvegicus albinus), machos, adultos (180-200 g), randomizados em três grupos: controle (n=10) não receberam agente ou veículo; sham (n=10) receberam solução veículo da estreptozotocina; e diabético (n=15) receberam estreptozotocina. Após oito semanas de indução do diabete melito, os animais foram pesados, anestesiados e tiveram sangue colhido da aorta abdominal para determinação dos valores de homocisteína plasmática total, fator von Willebrand e glicemia. RESULTADOS: O modelo experimental foi reprodutível em 100% dos animais. A média das concentrações plasmáticas de homocisteína foi: 7,9 µmol/l (controle); 8,6 µmol/l (sham) e 6,1 µmol/l (diabético), com diferença entre os grupos (p<0,01). Pelo método de comparações múltiplas entre os grupos, observou-se que os valores no grupo diabético foram menores que no sham (p<0,01). A média dos valores do fator von Willebrand foi 0,15 U/l (controle), 0,16 U/l (sham) e 0,18 U/l (diabético), com diferença entre os grupos (p=0,03). A média dos seus valores no grupo diabético foi maior que no grupo controle (p<0,05). No grupo diabético não houve correlação entre homocisteína e fator von Willebrand. CONCLUSÃO: No diabete melito induzido por estreptozotocina constataram-se valores reduzidos de homocisteína e elevados de fator von Willebrand, sem, contudo, haver correlações entre si e com níveis de glicemia final.Universidade Federal de São Paulo (UNIFESP) EPMUNIFESP, EPMSciEL

Efeito agudo da ingestão de concentrado de uva sobre os biomarcadores do estresse oxidativo em triatletas

The aim of this crossover study was to evaluate the effect of a grape concentrate (test drink [TD]) on oxidative stress markers (thiobarbituric acid reactive substances [TBARS], catalase [CAT], superoxide dismutase [SOD], and glutathione [GSH]). Six triathletes had their physical fitness, body fat composition (%BF) and food intake evaluated. Afterwards, the athletes received two doses of 300 mL of the TD (45.8g of polyphenols/kg) or a placebo drink (PL), at breakfast and after a training session (100 km of cycling, 6 km of running and 1.5 km of swimming). Blood samples (5 ml) were collected after an overnight fasting, immediately after exercise, and one hour after exercise. The triathletes presented the following characteristics (mean and standard-deviation): 43.8±10.2 years old, VO2máx 45±5.15 mL/kg/min, %BF 13.6±4.2 %, training 270.8±87.1 km/week, 3.1±1.88 hours/training/day. There was a significant increase in SOD from the 1st to the 2nd (p=0.027) and 3rd (p=0.02) blood tests, in response to exercise, regardless of the drink consumed. One hour after exercise, the increase in glutathione values was greater when the PL was consumed (27.5%) in relation to the TD intake (1.8%). In both tests, exercise increased TBARS values; however, when PL was consumed, subjects' values were higher (PL=2.5±1.1 nmol/ml vs. BT=1.77±1.3 nmol/ml). When PL was consumed, mean CAT values (BT=34.2±6.9 U/mgHb vs. PL=24.6±12.5 U/mgHb) reduced from the 1st to the 2nd blood test (28.6%). TBARS, CAT and GSH values suggest that the TD presents potential to modulate exercise-induced oxidative stress.O objetivo deste estudo crossover foi avaliar o efeito de um concentrado de uva (bebida teste - BT) sobre biomarcadores do estresse oxidativo (substâncias reativas ao ácido tiobarbitúrico - TBARS, catalase - CAT, superóxido dismutase - SOD e glutationa - GSH). Seis triatletas do sexo masculino foram avaliados quanto à aptidão física, percentual de gordura (%G) e ingestão alimentar. Posteriormente, em duas ocasiões, os atletas receberam duas doses de 300 ml de BT (45,8g de polifenóis/kg) ou bebida placebo (PL) no desjejum e após uma sessão de treinamento (100 km de ciclismo, 6 km de corrida e 1,5 km de natação). Amostras de sangue (5 ml) foram coletadas em jejum, imediatamente após o exercício e 1h após o mesmo. Caracterização da amostra: idade: 43,8±10,2 anos, VO2máx: 45±5,15 ml/kg/min, %G: 13,6±4,2%, volume de treino: 270,8±87,1 km/semana e 3,1±1,88 horas/treino/dia. Houve aumento significativo da atividade de SOD da 1ª para as 2ª (p=0,027) e 3ª coletas (p=0,02) em resposta ao exercício, independente da bebida consumida. Os valores de GSH foram superiores 1 hora após o exercício quando houve consumo do PL (27,5%) em relação ao consumo da BT (1,8%). Ainda, o exercício elevou as concentrações de TBARS, mas no grupo PL os valores médios foram superiores (PL=2,5±1,2 nmol/ml vs. BT=1,77±1,3 nmol/ml). Em relação à atividade da CAT, os valores médios (BT=34,2±6,9 U/mgHb vs. PL=24,6±12,5 U/mgHb) foram menores quando comparadas 1ª e 2ª coletas (28,6%) para os atletas que consumiram PL. Os resultados referentes à concentração de TBARS, atividade de CAT e níveis de GSH sugerem que a BT modulou o estresse oxidativo induzido pelo exercício.Universidade Federal de São Paulo (UNIFESP)Universidade Federal de São Paulo (UNIFESP) Departamento de Ciências do Movimento HumanoUniversidade Federal de São Paulo (UNIFESP) Departamento de BiociênciasUniversidade Federal de São Paulo (UNIFESP) Departamento de PsicobiologiaUNIFESP, Depto. de Ciências do Movimento HumanoUNIFESP, Depto. de BiociênciasUNIFESP, Depto. de PsicobiologiaSciEL

Moderate hyperhomocysteinemia provokes dysfunction of cardiovascular autonomic system and liver oxidative stress in rats

Hyperhomocysteinemia (HHcy) is associated with cardiovascular disease, atherosclerosis and reactive oxygen species generation. Thus, our aim was to investigate whether there was an association between HHcy, blood pressure, autonomic control and liver oxidative stress. Male Wistar rats were divided into 2 groups and treated for 8 weeks: one group (control, CO) received tap water, while the other group (methionine, ME) was given a 100 mg/kg of methionine in water by gavage. Two catheters were implanted into the femoral artery and vein to record arterial pressure (AP) and heart rate (HR) and drug administration. Signals were recorded by a data acquisition system. Baroreflex sensitivity was evaluated by HR responses to AP changes induced by vasoactive drugs. HR variability and AP variability were performed by spectral analysis in time and frequency domains to evaluate the contribution of the sympathetic and parasympathetic modulation. Lipid peroxidation and antioxidant enzyme activities were evaluated by measuring superoxide dismutase, catalase and glutathione peroxidase in liver homogenates. the ME group presented a significant increase in systolic arterial pressure (118 +/- 9 vs 135 +/- 6 mm Hg), diastolic arterial pressure (81 +/- 6 vs. 92 +/- 4) and mean arterial pressure (95 +/- 7 vs. 106 +/- 6). in addition, pulse interval variability presented a significant decrease (41%), while the low frequency component of AP was significantly increased (delta P = 6.24 mmHg(2)) in the ME group. We also found a positive association between lipid peroxidation and cardiac sympathetic modulation, sympathetic and vagal modulation ratio and systolic pressure variability. Collectively, these findings showed that HHcy induced dysfunction of cardiovascular autonomic system and liver oxidative stress. (C) 2013 Elsevier B.V. All rights reserved.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)FAPERGSUniv Fed Rio Grande do Sul, Inst Ciencias Basicas Saude, Dept Fisiol, Lab Fisiol Cardiovasc, BR-90046900 Porto Alegre, RS, BrazilUniv São Paulo, Inst Coracao, Unidade Hipertensao, BR-05508 São Paulo, BrazilUniv Fed Ciencias Saude Porto Alegre, BR-90050170 Porto Alegre, RS, BrazilUniversidade Federal de São Paulo, Dept Biociencias, São Paulo, BrazilUniv Fed Rio de Janeiro, Inst Nutr Josue Castro, BR-21941 Rio de Janeiro, BrazilUniv Santo Amaro, Programa Posgrad Ciencias Saude, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biociencias, São Paulo, BrazilWeb of Scienc

Endocrinological and catecholaminergic alterations during sleep deprivation and recovery in male rats

Since previous data of our group showed increased concentrations in HPA axis hormones in sleep deprived rats, we hypothesized that this augmentation could produce effects in other hormonal systems, particularly in the sexual system. Considering that little is known about how the hormonal system changes during the recovery period after sleep deprivation (SD), our objective was to examine from what point SD alters sexual and stress-related hormones along with plasma catecholamine concentrations during 4 days. We also sought to verify the time course of their recovery after an equivalent period of recovery sleep. Rats were deprived of sleep by the platform technique for 1-4 days and were allowed to recover for the same period. Plasma catecholamines [dopamine (DA) and noradrenaline (NOR)], testosterone, estrone, progesterone, prolactin, corticosterone and adrenocorticotropic hormone (ACTH) concentrations were measured. Comparisons between groups showed that the SD procedure used in the present study produced marked alterations in almost all studied hormones from 24 h of SD, except for estrone and prolactin (which required 96 h of SD to become altered). Testosterone and estrone decreased, whereas progesterone, prolactin, corticosterone, ACTH, DA and NOR increased. During recovery period, progesterone, prolactin and corticosterone concentrations returned to control levels, whereas testosterone, estrone, NOR and DA did not. in addition, after 48 h of recovery ACTH and NOR decreased below control concentrations, remaining low until 96 h of sleep recovery. Thus, SD showed long lasting, differential effects upon these neurochemicals suggesting that each has its own pattern of responses to SD as well as variable periods of recovery

Screening for inborn errors of metabolism among newborns with metabolic disturbance and/or neurological manifestations without determined cause

CONTEXT: Inborn Errors of Metabolism are hereditary affections resulting from incompetence in enzymatic reactions of intermediary metabolism. At present, several hundred hereditary metabolic disturbances are known, many of which correspond to severe life-threatening disorders. OBJECTIVE: The early detection of carriers has motivated the screening for these disturbances among newborns at the Neonatal Unit of Hospital São Paulo, in an attempt to initiate support treatment, when available, before clinical manifestations become evident. DESIGN: Prospective study of risk patients. SETTING: Laboratory for Inborn Errors of Metabolism at the Center for Medical Genetics of the Departments of Pediatrics and Morphology of Universidade Federal de São Paulo (UNIFESP)/Escola Paulista de Medicina.Newborn care unit at a tertiary care hospital. PARTICIPANTS: 101 children admitted into the Neonatal Unit were included in this study by presenting hypoglycemia, metabolic acidosis, jaundice, difficulty in gaining weight, diarrhea, vomiting, hepato- and/or splenomegaly, cataracts, apnea, convulsions, hypo- or hypertonia. DIAGNOSTIC TESTS: Tests routinely utilized, performed for qualitative research of abnormal substances excreted in the urine in situations of metabolic disorder. RESULTS: Children were included in the study mainly because of presenting hypoglycemia, jaundice and metabolic acidosis. Sixty-four newborns presented at least one positive test result. Most of the positivity was due to transitory metabolic alterations of the newborn, such as the case of Transitory Neonatal Tyrosinemia, presented by 29 patients. Nine infants were referred to the Center for Medical Genetics of Universidade Federal de São Paulo (UNIFESP) for continuation of the diagnostic investigation. For three of them, the tests applied permitted us to formulate a diagnostic hypothesis of mucopolysaccharidosis, tyrosinemia type I and non-ketotic hyperglycinemia, respectively. CONCLUSIONS: The high positivity observed in the tests reflects the newborn's own metabolic immaturity. The selection of 9% of the studied cases for outpatient follow-up confirms that Inborn Errors of Metabolism must be suspected whenever a patient presents metabolic disturbances or neurological manifestations without a determined cause. They should be researched in parallel with the other diagnostic possibilities and not just taken to be exceptional diagnoses.CONTEXTO: Os erros inatos do metabolismo são afecções hereditárias resultantes da incompetência de reações do metabolismo intermediário. Atualmente já são conhecidos centenas de distúrbios metabólicos hereditários, muitos deles correspondendo a enfermidades graves que evoluem com freqüência para o óbito, ou causam seqüelas importantes, principalmente a deficiência mental. OBJETIVO: A possibilidade de detecção precoce de portadores motivou a triagem desses distúrbios entre recém-nascidos da Unidade Neonatal, na tentativa de iniciar o tratamento de suporte, quando disponível, antes que as manifestações clínicas fossem evidentes. TIPO DE ESTUDO: Estudo prospectivo. LOCAL: Unidade Neonatal em Hospital Terciário. PARTICIPANTES: 101 crianças internadas na Unidade neonatal foram incluídas no estudo por apresentarem hipoglicemia, acidose metabólica, icterícia, dificuldade de ganhar peso, diarréia, vômitos, hepato e/ou esplenomegalia, catarata, apnéia, convulsões, hipo ou hipertonia. TESTES APLICADOS: Testes realizados para pesquisa qualitativa de substâncias anormalmente excretadas na urina em situações de desordem metabólica. RESULTADOS: Os recém-nascidos foram incluídos no estudo principalmente por apresentarem hipoglicemia, icterícia e acidose metabólica. 64 recém-nascidos apresentaram pelo menos um teste com resultado positivo. A positividade foi devida principalmente a distúrbios metabólicos transitórios, como por exemplo a Tirosinemia Transitória do Recém-Nascido, apresentada por 29 pacientes. Nove crianças foram selecionadas e encaminhadas ao Centro Medico de Genética para continuação da investigação diagnóstica. Para três delas os testes aplicados permitiram a formulação de uma hipótese diagnóstica de mucopolissacaridose, tirosinemia tipo I e hiperglicinemia não-cetótica, respectivamente. CONCLUSÕES: A alta positividade observada nos testes reflete a imaturidade metabólica própria do recém-nascido. A seleção de 9% dos casos triados para acompanhamento ambulatorial confirma que os erros inatos do metabolismo devem ser suspeitados sempre que um paciente apresente distúrbios metabólicos ou manifestações neurológicas sem causa determinada, sendo pesquisados paralelamente às demais possibilidades diagnósticas e não apenas tidos como diagnósticos de exceção

Evaluation of oxidative stress markers and cardiovascular risk factors in Fabry Disease patients

Fabry Disease, an X-linked inborn error of metabolism, is characterized by progressive renal insufficiency, with cardio and cerebrovascular involvement. Homocysteine (Hcy) is considered a risk factor for vascular diseases, but the mechanisms by which it produces cardiovascular damage are still poorly understood. Regarding the vascular involvement in FD patients, the analysis of factors related to thromboembolic events could be useful to improving our understanding of the disease. The aim of this study was to evaluate plasma Hcy and other parameters involved in the methionine cycle, as well as oxidative stress markers. The sample consisted of a group of 10 male FD patients and a control group of 8 healthy individuals, paired by age. Venous blood was collected for Hcy determination, molecular analysis, identification of thiobarbituric acid reactive substances, total glutathione and antioxidant enzymes activity, as well as vitamins quantification. Comparative analysis of FD patients versus the control group indicated hyperhomocysteinemia in 8 of the 10 FD patients, as well as a significant increase in overall glutathione levels and catalase activity. It is inferred that FD patients, apart from activation of the antioxidant system, present increased levels of plasma Hcy, although this is probably unrelated to common alterations in the methionine cycle

Consequences of subchronic and chronic exposure to intermittent hypoxia and sleep deprivation on cardiovascular risk factors in rats

Since studies suggest that both hypoxia and sleep fragmentation are related to cardiovascular alterations induced by obstructive sleep apnea, the present study was designed to evaluate the effects of hypoxia, sleep deprivation, and their combination on biochemical blood parameters in rats. in subchrome experiments (4 days), rats were exposed to intermittent hypoxia (IH) during the light period (2 min room air-2 min 10% O-2 for 12 h/day) and/or paradoxical sleep deprivation (PSD, 24 h/day). Consequences of chronic intermittent hypoxia (CIH) exposure were examined after 21 consecutive days of hypoxia protocol from 10:00 to 16:00 followed by a sleep restriction (SR) period of 18 h (16:00-10:00). Rats were randomly assigned to seven treatment groups: (1) control (2) IH (3) PSD (4) IH-PSD (5) SR (6) CIH and (7) CIH-SR. PSD reduced triglycerides and very low-density lipoprotein (VLDL) cholesterol concentrations and increased total cholesterol and high-density lipoprotein (HDL) cholesterol. IH did not alter any of these parameters. the combination of IH-PSD did not modify the values of total cholesterol and HDL compared to control group. in the chronic experiment, the animals exposed to CIH displayed a reduction of Vitamin B-6 and an increase of triglycerides and VLDL. Our findings show a duration-dependent effect of hypoxia on triglycerides. Rats in the SR and CIH-SR groups showed a diminished concentration of triglycerides and VLDL. SR rats showed a reduction in the concentration of homocysteine but the animals in the CIH-SR treatment condition did not display any alterations in this parameter. in this latter group, an augmentation of cysteine concentration was observed. These results suggest that sleep deprivation and hypoxia modify biochemical blood parameters in distinct ways. (C) 2006 Elsevier B.V. All rights reserved.Universidade Federal de São Paulo, Dept Psychobiol, BR-04024002 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Hlth Sci, BR-04024002 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Physiol, BR-04024002 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Psychobiol, BR-04024002 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Hlth Sci, BR-04024002 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Physiol, BR-04024002 São Paulo, BrazilWeb of Scienc

The p.T191M mutation of the CBS gene is highly prevalent among homocystinuric patients from Spain, Portugal and South America (vol 51, pg 305, 2007)

Univ Barcelona, Fac Biol, Dept Genet, E-08028 Barcelona, SpainUniv Nacl Cordoba, Ctr Estudio Metab Congenitas, RA-5000 Cordoba, ArgentinaPontificia Univ Javeriana, Inst Genet Humana, Bogota, ColombiaUniv Antioquia, Fac Med, Dept Fisiol & Bioquim, Medellin, ColombiaFdn Estudio Enfermedades Neurometab, Buenos Aires, DF, ArgentinaInst Genet Med Jacinto Magalhaes, Oporto, PortugalUniversidade Federal de São Paulo, EPM, UNIFESP, Dept Pediat, São Paulo, BrazilHosp Ramon & Cajal, Serv Pediat, Unidad Enfermedades Metab, E-28034 Madrid, SpainHosp Univ Materno Infantil, Unidad Gastroenterol & Nutr, Las Palmas Gran Canaria, SpainHosp Infantil La Fe, Unidad Nutr & Metab, Valencia, SpainHosp Clin Univ Santiago, Dept Pediat, Santiago de Compostela, SpainCorp Sanitaria Clin, Inst Bioquim Clin, Barcelona, SpainHosp St Joan Deu, Serv Bioquim, Barcelona, SpainUniversidade Federal de São Paulo, EPM, UNIFESP, Dept Pediat, São Paulo, BrazilWeb of Scienc