RESUMO
Due to the utilization of milk proteins such as whey protein (WP) and casein as sports nutrition ergogenic aids, the present study investigated the effects of the association of WP and casein in a ratio of 80:20, a similar ratio of human breast milk, on blood branched-chain amino acid (BCAA) profiles, markers of protein metabolism and delayed onset muscle soreness (DOMS), after a single bout of resistance exercise. A double-blind, crossover and acute study was carried out with ten men (age 29 ± 8 years; BMI: 25.4 ± 2.9 kg/m2; 77 ± 12 kg; 1.74 ± 0.09 m); each one consumed the following supplements randomly, one per session: WP, CAS (casein), WP/CAS (80% WP/20% CAS), CAS/WP (80% CAS/20% WP) and PLA (placebo). They were also subjected to the following evaluations: the one repetition maximum (1RM) test; resistance training session; blood extraction during each session to determine the BCAA profile; two food records; 3-day evaluation of DOMS (24 h, 48 h and 72 h) and nitrogen balance in each treatment. The intervention resulted in similar nitrogen urinary, creatinine and urea plasma levels and showed a positive nitrogen balance in all the trials. Regarding the BCAAs, the peak occurred at 60 min post-ingestion and remained higher until 120 min for WP, WP/CAS and CAS/WP. The DOMS was significantly lower for WP, WP/CAS and CAS/WP compared to the CAS and PLA treatments. There were no advantages in the association of WP and CAS in the BCAAs profile when compared to WP itself, but it induced a lower DOMS compared to CAS and PLA (Clinical Trial registration number: clinicaltrials.gov, NCT04648384).
Assuntos
Caseínas/análise , Exercício Físico/fisiologia , Leite Humano/química , Proteínas do Soro do Leite/análise , Adulto , Aminoácidos de Cadeia Ramificada/análise , Biomarcadores/metabolismo , Humanos , Masculino , Mialgia/patologiaRESUMO
BACKGROUND/AIMS: Chronic renal patients on hemodialysis (HD) and peritoneal dialysis (PD) treatment are exposed to oxidative stress and DNA damage. The objective of this study was to assess the oxidative damage to DNA in end-stage chronic renal failure, before and after vitamin E supplementation. METHODS: Patients on HD (n=29) and PD (n=22) received oral supplementation with 300 mg vitamin E three times a week for 4 weeks. A blood sample was collected at the beginning and at the end of the supplementation cycle for the determination of vitamin E levels (high-performance liquid chromatography), carbonyl groups, and DNA damage (8-hydroxy 2'-deoxyguanosine [8-OHdG] and comet assay). RESULTS: After supplementation, vitamin E concentration was increased by about 50%. Protein oxidation was initially observed in both groups, with a reduction after supplementation. DNA damage detected by the comet assay and by 8-OHdG analysis was significantly reduced (p<0.05) after supplementation in both groups. CONCLUSIONS: Vitamin E supplementation reduced oxidative DNA damage in both HD and PD patients. Treatments such as HD and PD induce oxidative stress and consequent DNA damage, and increased plasma vitamin E levels significantly contribute to the normalization of these events.
Assuntos
Antioxidantes/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Diálise Renal/efeitos adversos , Vitamina E/administração & dosagem , Adulto , Distribuição por Idade , Brasil/epidemiologia , Estudos de Casos e Controles , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Incidência , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Oxirredução , Diálise Peritoneal Ambulatorial Contínua/métodos , Probabilidade , Valores de Referência , Diálise Renal/métodos , Medição de Risco , Distribuição por Sexo , Estatísticas não Paramétricas , Resultado do TratamentoRESUMO
The effect of citric pectin on the bioavailability of synthetic beta-carotene was studied. Thirty Wistar rats were used, ten animals were sacrificed at the beginning of the experiment and remaining animals were divided into two groups and received the following diets for 30 days: control group (CG)--24 micrograms beta-carotene/g diet + 0% citric pectin; experimental group (EG)--24 micrograms beta-carotene/g diet + 7% citric pectin. Plasma and liver beta-carotene, vitamin A, and retinyl palmitate concentrations were determined by high-performance liquid chromatography (HPLC). Plasma retinol concentration was 1.42 +/- 0.36 mumol/L for CG and 1.10 +/- 0.24 mumol/L for EG (p = 0.1), and plasma beta-carotene concentration was 0.20 +/- 2.51 mumol/L for CG and 0.07 +/- 0.04 mumol/L for EG (p = 0.01). Only traces of retinyl palmitate were detected in CG and none in EG. Retinol did not differ significantly between groups CG and EG, while a significantly higher beta-carotene concentration was observed for CG. Liver concentrations of retinol (CG: 4.90 +/- 2.51 micrograms/g; EG: 2.68 +/- 1.12 micrograms/g), beta-carotene (CG: 0.98 +/- 0.28 microgram/g; EG: 0.11 +/- 0.06 microgram/g), and retinyl palmitate (CG: 95.47 +/- 45.13 micrograms/g, EG: 37.01 +/- 17.20 micrograms/g) differed significantly between groups (p < 0.05), with a lower concentration being observed for EG. We conclude that 7% citric pectin in the rat diet decreases the bioavailability of synthetic beta-carotene, reducing the liver reserves of vitamin A and beta-carotene.
Assuntos
Antioxidantes/farmacocinética , Fígado/metabolismo , Pectinas/farmacologia , Vitamina A/análogos & derivados , Vitamina A/metabolismo , beta Caroteno/farmacocinética , Animais , Antioxidantes/metabolismo , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Diterpenos , Masculino , Ratos , Ratos Wistar , Ésteres de Retinil , Vitamina A/sangue , beta Caroteno/metabolismoRESUMO
A geraçäo de radicais livres é um passo importante na patogênese da injúria hepática, associada à ingestäo de etanol. O etanol induz a aumento na peroxidaçäo lipídica por dois mecanismos: maior produçäo de espécies reativas de oxigênio e/ou diminuiçäo dos níveis dos antioxidantes endógenos. Este trabalho enfoca a geraçäo de radicais livres em ratos, após a ingestäo crônica de etanol na água (20 por cento), pelo período de 4 semanas. O objetivo do trabalho foi investigar o efeito do etanol sobre a peroxidaçäo lipídica plasmática e hepática (medida por SRATB), vitamina E em plasma e fígado e glutationa hepática. Os animais receberam etanol por um período experimental de 4 semanas e foram sacrificados em 2 períodos distintos: 0 hora após o término das 4 semanas e 24 horas após o etanol ser retirado e substituído por água. Os animais que receberam etanol mostraram uma ingestäo alimentar diminuída e alcançaram um peso menor, quando comparados aos ratos que receberam apenas água durante o experimento (p < 0,05). O grupo sacrificado 24 horas após, demonstrou a concentraçäo mais baixa de vitamina E hepática (5,96±3,30 µg/g) em relaçäo ao Grupo-Controle (35,78±9,23 µg/g) e ao Grupo Etanol 0 horas (10,30±1,59 µg/g). As concentrações hepáticas de SRATB foram encontradas em níveis aumentados nos animais que receberam etanol. Os valores de glutationa também foram afetados e se mostraram aumentados. Conclui-se que a administraçäo crônica de etanol leva a uma alteraçäo no sistema de defesa antioxidante, diminuindo os valores de vitamina E e aumentando os valores de GSH, provocando maior peroxidaçäo lipídica
