Background: Paraoxonase-1 (PON1) is an antioxidative enzyme associated with HDL and its serum activity is associated with risk of cardiovascular disease. The interindividual variation in PON1 activity is partly determined by genetic factors, such as polymorphisms in the PON1 gene, but also by dietary factors like the antioxidants.
Aim Of The Study: We examined the effect of antioxidant-rich orange and blackcurrant juices and vitamin E supplement on PON1 activity in patients with peripheral arterial disease.
Background: HDL-associated paraoxonase (PON1) reduces oxidation of lipids in LDL, and activity is inversely related to coronary heart disease risk with a beneficial effect on the development of atherosclerosis. Risk factors associated with atherosclerosis, such as hypertension, dyslipidemia and smoking, also promote the progression of chronic glomerulonephritides which may therefore be associated with perturbations in PON1 activity.
Methods: We performed a genetic association study in patients with IgA nephropathy (IgAN) (n=115) compared with control subjects (n=118).
Human serum paraoxonase 1 (PON1), a high-density lipoprotein (HDL)-associated enzyme, has been shown to reduce the oxidation of low-density lipoprotein (LDL) and HDL by degrading lipid peroxides. This property of PON1 accounts for its ability to protect against atherosclerosis. In this study, we identified four polymorphisms in both the coding (L55M and Q192R) and regulatory regions (T-108C and G-909C) of the human PON1 gene in 202 healthy Thai individuals and investigated the influence of these polymorphisms on serum PON1 activity towards three substrates, namely, paraoxon, phenylacetate and diazoxon.
View Article and Find Full Text PDFObjective: Medroxyprogesterone (MP) was used as the progestogen in randomized clinical trials of postmenopausal hormone replacement on cardiovascular risk. To attempt to understand the lack of benefit in these trials, we have examined the effects of MP and two other progestogens, the less androgenic desogestrel (DG) and the more androgenic norethisterone (NE), on cardiovascular risk factors against a background of oestrogen therapy.
Design And Measurements: Thirty-four women were treated with conjugated equine oestrogens (CEE) 0.
Lancet
September 2004
Background: Type 2 diabetes is associated with a substantially increased risk of cardiovascular disease, but the role of lipid-lowering therapy with statins for the primary prevention of cardiovascular disease in diabetes is inadequately defined. We aimed to assess the effectiveness of atorvastatin 10 mg daily for primary prevention of major cardiovascular events in patients with type 2 diabetes without high concentrations of LDL-cholesterol.
Methods: 2838 patients aged 40-75 years in 132 centres in the UK and Ireland were randomised to placebo (n=1410) or atorvastatin 10 mg daily (n=1428).
The antioxidant activity of high density lipoprotein (HDL) is largely due to the paraoxonase (PON) 1 located on it. Experiments with transgenic PON1 knockout mice indicate the potential for PON1 to protect against atherogenesis. This effect of HDL in decreasing low density lipoprotein (LDL) lipid peroxidation is maintained for longer than that of antioxidant vitamins and could therefore be more protective.
View Article and Find Full Text PDFSmall-dense low-density lipoprotein (SD-LDL) is associated with coronary heart disease risk. Current methods for its quantification are expensive, complex and time-consuming. Plasma was adjusted to a density (D) of 1.
View Article and Find Full Text PDFSerum paraoxonase (PON1) is a high-density lipoprotein (HDL) associated protein, which plays a critical role in the pathogenesis of atherosclerosis, although it was primarily associated with the hydrolysis of organophosphorus compounds. PON1 was initially thought to be independent from physiological or pathological states, although recently some environmental factors have been reported to modulate its activity. In this study, we have investigated the promoter (PON1 -108C/T and -909 C/G) and coding region (PON1 192Q/R and 55L/M) polymorphisms, as well as PON1 activity towards different substrates (paraoxon, phenylacetate and diazoxon) in 102 individuals with long term low dose exposure to pesticides in a plastic greenhouse setting (sprayers), who are probably the group of agricultural workers with the highest exposure to pesticides.
View Article and Find Full Text PDFBackground: Existing methods for detecting small-dense low-density lipoprotein (SD-LDL) are either semiquantitative (e.g., gradient gel electrophoresis) or require specialised laboratory methods (e.
View Article and Find Full Text PDFSerum paraoxonase (PON1) is responsible for the metabolism of organophosphates in serum, and PON1 activity is a major determinant of their toxicity in humans. There have been reports linking lowered PON1 activity to physical symptoms after deployment to the Persian Gulf War (PGW) of 1990 to 1991. Therefore, the object of this study was to determine (1) whether PON1 activity was decreased among symptomatic PGW veterans compared with asymptomatic PGW veterans and (2) to determine whether PGW veterans as a whole had lower PON1 activity compared with other military control groups.
View Article and Find Full Text PDFThe antioxidant activity of HDL is largely due to the paraoxonase (PON1) located on it. Experiments with transgenic PON1 knock-out mice indicate the potential for PON1 to protect against atherogenesis. This effect of HDL in decreasing LDL lipid peroxidation is maintained for longer than that of antioxidant vitamins and could thus be more protective.
View Article and Find Full Text PDFPurpose Of Review: The antioxidant activity of high-density lipoprotein is largely due to the paraoxonase 1 located on it. Experiments with transgenic paraoxonase 1 knock-out mice indicate the potential for this enzyme to protect against atherogenesis. This effect of high-density lipoprotein in decreasing low-density lipoprotein lipid peroxidation is maintained for longer than that of antioxidant vitamins and could thus be more protective.
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