The beneficial effects of virgin olive oil against oxidative stress induced by hypercholesterolemia in rats

Cardiovascular disease(CVD) remains the major cause of mortality in the world, typically claiming a third of all deaths. The primary cause of CVD is atherosclerosis. Therefore, timely prevention and therapy of atherosclerosis are able to reduce the risk of the development of its clinical manifestations. Anti-atherosclerotic activity of medicinal plants mainly appears in their multiple effects.This study was carried out to evaluate the hypolipidemic activity of virgin olive oil in experimentally induced hyperlipemic Wistar. A total of 24 rats were randomly allocated to 4 equal groups and treated as follows for 50 days: (1) Normal control (NC); that were fed with a standart diet; (2) High Cholesterol Diet Control (HCD); which received high cholesterol diet for 50 days; (3) Animals receiving high cholesterol diet for 50 days, after this period the animals are fed for eight days by the standard foodand receiving by gavage virgin olive oil (HCD+VOO) and(4) Animals fed for eight days with the standard food and receiving by gavage olive oil (VOO). High Cholesterol Diet containing yolk egg and coconut oil. Results showed that olive oil caused a significant (p < 0.01) reduction in serum levels of Total Cholesterol (TC), Triglycerides (TG), Low­Density Lipoprotein Cholesterol (LDL) and Atherogenic Index Serum (AIS). The results also demonstrated a significant (p < 0.01) increase in High­Density Lipoprotein Cholesterol (HDL). Moreover, virgin olive oil induced a significant reduction in liver lipid content. On the other hand, a High cholesterol diet induced oxidative stress was measured by estimating reduced glutathione level and amount of thiobarbituric acid reactive substances (TBARS) formed as an index of lipid peroxidation in a liver and a heart. Virgin olive oil supplementation attenuated all these variations. Our observations of the study indicate that the virgin olive oil has a significant antihyperlipidemic potential.

Antibodies against electronegative LDL inhibit atherosclerosis in LDLr-/- mice

In order to determine the effect of antibodies against electronegative low-density lipoprotein LDL(-) on atherogenesis, five groups of LDL low receptor-deficient (LDLr-/-) mice (6 per group) were immunized with the following antibodies (100 µg each): mouse anti-LDL(-) monoclonal IgG2b, rabbit anti-LDL(-) polyclonal IgG or its Fab fragments and mouse irrelevant monoclonal IgG and non-immunized controls. Antibodies were administered intravenously one week before starting the hypercholesterolemic diet (1.25 percent cholesterol) and then every week for 21 days. The passive immunization with anti-LDL(-) monoclonal IgG2b, polyclonal antibody and its derived Fab significantly reduced the cross-sectional area of atherosclerotic lesions at the aortic root of LDLr-/- mice (28.8 ± 9.7, 67.3 ± 17.02, 56.9 ± 8.02 µm² (mean ± SD), respectively) compared to control (124.9 ± 13.2 µm²). Vascular cell adhesion molecule-1 protein expression, quantified by the KS300 image-analyzing software, on endothelium and the number of macrophages in the intima was also decreased in aortas of mice treated with anti-LDL(-) monoclonal antibody (3.5 ± 0.70 per field x 10) compared to controls (21.5 ± 3.5 per field x 10). Furthermore, immunization with the monoclonal antibody decreased the concentration of LDL(-) in blood plasma (immunized: 1.0 ± 1.4; control: 20.5 ± 3.5 RLU), the amount of cholesterol oxides in plasma (immunized: 4.7 ± 2.7; control: 15.0 ± 2.0 pg COx/mg cholesterol) and liver (immunized: 2.3 ± 1.5; control: 30.0 ± 26.0 pg COx/mg cholesterol), and the hepatic content of lipid hydroperoxides (immunized: 0.30 ± 0.020; control: 0.38 ± 0.15 ng/mg protein). In conclusion, antibodies against electronegative LDL administered intravenously may play a protective role in atherosclerosis.

Oxidative stress in sepsis in children.

BACKGROUND & OBJECTIVE: Information on oxidative damage during sepsis in children is not available, we undertook this study to assess the levels of certain antioxidants in blood of children with sepsis. METHODS: Study group had 38 children with sepsis (<5 yr) and 39 age-and sex-matched controls admitted to a tertiary care hospital. Red cell glutathione (GSH), superoxide dismutase (SOD) and thiobarbituric acid reactive substance (TBARS) and plasma vitamin C were estimated by standard techniques. RESULTS: There was no significant change in erythrocyte GSH, SOD and TBARS levels in sepsis when compared to controls. This may be due to the adaptive response of the body to combat the oxidative stress. However, plasma vitamin C levels were significantly reduced in patients aged one year one month to five years which may be due to active phagocytosis and due to its role as a free radical scavenger. INTERPRETATION & CONCLUSION: Our findings show that children affected by sepsis probably adapt to the free radical toxicity induced by this condition. Further studies need to be done on a larger sample to confirm the findings.

Dust-mites: effect on lipid peroxidation.

BACKGROUND: Dust-mites are present in our homes, feed on dead exfoliated skin and other organic material. It is also known that oxidative stress may lead to cellular damage that can be confirmed by markers of cellular disruption. Oxidative stress in various infective processes has been documented. We investigated whether house dust-mites cause oxidative stress in patients. METHODS: Products of lipid peroxidation in erythrocytes and lymphocytes were assessed by measuring malondialdehyde concentration. RESULTS: Our results showed that patients who had a positive skin test for dust-mite antigens and had dust-mites present in their houses (dust-mite positive) had increased erythrocyte malondialdehyde levels (62.39 [18.56] nmol/g-Hb) compared with those who were skin test positive, dust-mite negative (45.45 [10.82]) or skin test negative, dust-mite negative (42.20 [5.68]). They also had significantly higher levels of lymphocyte malondialdehyde (4.22 [0.55] nmol/g-protein) compared with those who were skin test positive, dust-mite negative (3.46 [0.29]) or skin test negative, dust-mite negative (1.25 [0.31]; p <0.05). However, there was no statistically significant difference between the malondialdehyde levels of dust-mite negative/skin test positive and dust-mite negative/skin test negative patients. CONCLUSION: Increased malondialdehyde activity in lymphocytes and erythrocytes in the dust-mite positive/skin test positive group shows the presence of the oxidative stress in patients with dust-mite infestation.

Peroxidaçäo lipídica e antioxidantes no lúpus eritematoso sistêmico / Lipid peroxidation and antioxidants in Systemic Lupus Erythematosus

O estresse oxidativo está relacionado ao Lúpus Eritematoso Sistêmico (LES) e é provável que o desequilíbrio entre a geraçäo de radicais livres e antioxidantes esteja envolvido com o agravamento do estado de saúde. Objetivo: Estudar a peroxidaçäo lipídica e componentes de defesa antioxidante no LES. Casuística e métodos: Foram estudados 54 pacientes com LES. separados em dois grupos: Grupo Doença Ativa (n=25) e Grupo Doença Inativa (n=29) e 12 controles. Para o Grupo Doença Ativa, dois subgrupos foram constituídos considerando o status do processo inflamatório: Agudo e Crônico. Foi analisada a oxidaçäo de lipídios [malondialdeído (MDA)]; de proteínas (grupo carbonila) e de DNA (Teste de SOD)...

Peroxidação lipídica e antioxidantes no Lúpus Eritematoso Sistêmico / Lipid peroxidation and antioxidants in Systemic Lupus Erythematosus

O estresse oxidativo está relacionado ao Lúpus Eritematoso Sistêmico (LES) e é provável que o desequilíbrio entre a geração de radicais livres e antioxidantes esteja envolvido com o agravamento do estado de saúde. Objetivo: Estudar a peroxidação lipídica e componentes de defesa antioxidante no LES. Casuística e métodos: Foram estudados 54 pacientes com LES, separados em dois grupos: Grupo Doença Ativa (n=25) e Grupo Doença Inativa (n=29) e 12 Controles. Para o Grupo Doença Ativa, dois subgrupos foram constituídos considerando o status do processo inflamatório: agudo e crônico. Foi analisada a oxidação de lipídios [malondialdeído (MDA)]; de proteínas (grupo carbonila) e de DNA (Teste do Cometa)...