The effect of red grape seed extract on serum paraoxonase activity in patients with mild to moderate hyperlipidemia / O efeito do extrato de semente de uva vermelha na atividade do soro paraoxonase em doentes com hiperlipidemia leve a moderada

ABSTRACT: CONTEXT AND OBJECTIVE: Red grape seed extract (RGSE) contains oligomeric proanthocyanidin complexes as a class of flavonoids. These compounds are potent antioxidants and exert many health-promoting effects. This study aimed to determine the effects of RGSE on serum levels of triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoprotein AI (apo-AI) levels and paraoxonase (PON) activity in patients with mild to moderate hyperlipidemia (MMH). DESIGN AND SETTINGS: A randomized double-blind placebo-controlled clinical trial was conducted at Shahid-Modarres Hospital (Tehran, Iran) and Tabriz University of Medical Sciences. Seventy MMH patients were randomly assigned to receive treatment (200 mg/day of RGSE) or placebo for eight weeks. RESULTS: Significant elevation in serum levels of apo-AI (P = 0.001), HDL-C (P = 0.001) and PON activity (P = 0.001) and marked decreases in concentrations of TC (P = 0.015), TG (P = 0.011) and LDL-C (P = 0.014) were found in the cases. PON activity was significantly correlated with apo-AI (r = 0.270; P < 0.01) and HDL-C (r = 0.45; P < 0.001). Significant differences between the RGSE and control groups (before and after treatment) for TC (P = 0.001), TG (P = 0.001), PON (P = 0.03), apo-AI (P = 0.001) and LDL-C (P = 0.002) were seen. CONCLUSION: It is possible that RGSE increases PON activity mostly through increasing HDL-C and apo-AI levels in MMH patients. It may thus have potential beneficial effects in preventing oxidative stress and atherosclerosis in these patients.

RESUMO: CONTEXTO E OBJETIVO: Extrato de semente de uva vermelha (RGSE) contém complexos de proantocianidinas oligoméricas como classe de flavonoides. Estes compostos são antioxidantes potentes e exercem muitos efeitos de promoção da saúde. Este estudo visou determinar os efeitos de RGSE nos níveis séricos de triglicérides (TG), colesterol total (TC), colesterol de lipoproteína alta-densidade (HDL-C), colesterol de lipoproteína baixa-densidade (LDL-C), apolipoproteína AI (apo-AI) e atividade de paraoxonase (PON) em pacientes com hiperlipidemia leve a moderada (MMH). DESENHO E LOCAL: Estudo clínico randomizado duplo-cego controlado com placebo, realizado no Hospital Shahid-Modarres (Teerã, Irã) e na Universidade de Ciências Médicas de Tabriz. Setenta pacientes com MMH foram aleatoriamente designados para receber tratamento (200 mg/dia de RGSE) ou placebo durante oito semanas. RESULTADOS: Elevação significativa nos níveis séricos de apo-AI (P = 0,001), HDL-C (P = 0,001) e atividade de PON (P = 0,001) e diminuição marcada nas concentrações de TC (P = 0,015), TG (P = 0,011) e LDL-C (P = 0,014) foram encontradas nos casos. Atividade de PON mostrou correlação significativa com apo-AI (r = 0,270; P < 0,01) e HDL-C (r = 0,45; P < 0,001). Diferenças significativas entre os grupos RGSE e controle (antes e após tratamento) para TC (P = 0,001), TG (P = 0,001), PON (P = 0,03), apo-AI (P = 0,001) e LDL-C (P = 0,002) foram observadas. CONCLUSÃO: É possível que RGSE aumente atividade de PON principalmente através da elevação dos níveis de HDL-C e apo-AI em pacientes MMH. Ele pode, assim, ter efeitos benéficos potenciais na prevenção de estresse oxidativo e aterosclerose nesses pacientes.

Protective Effect of Fish Oil Supplementation on DNA Damage Induced by Cigarette Smoking.

The study examined the influence of fish oil (FO) supplementation on serum 8-hydroxy-2’-deoxyguanosine (8-OHdG) levels as indicated by DNA damage markers and total antioxidant capacity (TAC) among male cigarette smokers. This double-blind, placebo-controlled randomized study was conducted among healthy cigarette smokers (n=40) who were part of a larger prospective cohort study. Twenty smokers were randomly selected to receive FO for 3 months (1 g/day), and another 20 smokers received a placebo for 3 months; 8-OHdG and TAC levels were measured in blood samples before and after the intervention. Serum 8-OHdG significantly decreased (p=0.001) and TAC increased (p<0.001) after 3 months of treatment with FO. Between baseline and endline, the difference in 8-OHdG significantly correlated with the difference in TAC among smokers who received FO (r=-0.540, p=0.014). The study provides evidence that FO supplementation can modify decreased antioxidants and increased oxidative DNA damage in cigarette smokers.

Preventive effect of onion juice on selenite-induced experimental cataract.

Purpose: To evaluate the effects of onion juice on sodium-selenite induced cataract formation. Materials and Methods: Thirty-two 10-day-old Wistar-albino rat pups were divided into four equal groups. Group 1 received only subcutaneous saline injection. In Group 2, sodium-selenite (30 nmol / g body weight) was injected subcutaneously. In Group 3, subcutaneous sodium-selenite was injected and one drop 50% diluted fresh juice of crude onion was instilled every 8 h into the right eye for 14 days; the left eye received no treatment. Group 4 rats were similar to those of Group 3, the only difference being that of undiluted fresh juice of crude onion. The development of cataract was assessed. Rat lenses were analyzed for total antioxidant (TA) level, and for activities of glutathione peroxidase (GPX) and superoxide dismutase (SOD). Results: Both eyes of all rats in Group 1 did not exhibit cataract formation . In Group 2, all rats developed Grade 3 cataract in the lenses of both eyes. The difference in exhibited cataract in the lens of the right eyes in all rats between Group 2 and any eyes of groups 3 or 4 were significant ( P = 0.001). The mean TA level and mean activities of SOD and GPX in Group 2 rat lenses were significantly lower than the values in lenses of all rats in Group 1 ( P = 0.001, 0.003, 0.001), and in the lenses of the right eyes of rats in Groups 3 and 4 ( P = 0.001, 0.020, 0.001). Conclusion: Instillation of onion juice into the rat eyes can effectively prevent selenite-induced cataract formation. This effect was associated with increased TA level, SOD and GPX activities in the lens.