Serum paraoxonase 1 (PON1) is a native lactonase capable of promiscuously hydrolyzing a broad range of substrates, including organophosphates, esters, and carbonates. Structurally, PON1 is a six-bladed β-propeller with a flexible loop (residues 70-81) covering the active site. This loop contains a functionally critical Tyr at position 71. We have performed detailed experimental and computationa...

Various mechanisms may contribute to the antiatherogenic potential of apolipoprotein A-I (apo A-I) and high density lipoproteins (HDLs). Therefore, the effect of adenovirus-mediated human apo A-I gene transfer or human apo A-I transgenesis on platelet-activating factor acetylhydrolase (PAF-AH) and arylesterase/paraoxonase (PON1) was studied in C57BL/6 and C57BL/6 apo E(-/-) mice. Human apo A-I ...

Phosphorothioate pesticides (OP) such as diazinon, chlorpyrifos, and parathion are activated to highly toxic oxon metabolites by the cytochromes P450 (P450s), mainly in the liver. Simultaneously, the P450s catalyze detoxification of OP to nontoxic dearylated metabolites. The oxon is then detoxified to the dearylated metabolite by PON1, an A-esterase present in the liver and blood serum. The aim...

Infants are extremely vulnerable to certain pesticide exposures because they are still developing the ability to produce the enzyme para­ oxonase­1 (PON1), which detoxifies certain organophosphate pesti­ cides such as chlorpyrifos and diazinon. A study published in 2003 indicated that children may reach near­adult levels of PON1 activ­ ity by age 2 years. But a new larger­scale study of partici...

Infants are extremely vulnerable to certain pesticide exposures because they are still developing the ability to produce the enzyme para­ oxonase­1 (PON1), which detoxifies certain organophosphate pesti­ cides such as chlorpyrifos and diazinon. A study published in 2003 indicated that children may reach near­adult levels of PON1 activ­ ity by age 2 years. But a new larger­scale study of partici...

Background Oxidative stress and antioxidants have been implicated in many diseases including prostate cancer and benign prostatic hyperplasia (BPH). Lipid peroxidation contributes to oxidative stress. However, new and emerging antioxidants such as paraoxonase 1 (PON1) and arylesterase (ARE) associated with lipoprotein peroxidation have not been examined in BPH patients. PON1 and ARE, a high-den...

In a cross-sectional study, oxidative stress in high vascular disease risk groups, ESRD (end-stage renal disease) and Type I diabetes, was assessed by measuring plasma protein carbonyls and comparing antioxidant capacity of HDL (high-density lipoprotein) as pertaining to PON1 (paraoxonase 1) activity and in vitro removal of LPO (lipid peroxides). ESRD subjects on haemodialysis (n=22), Type I di...

BACKGROUND The activity of paraoxonase 1 (PON1), an antioxidant enzyme whose polymorphisms have been associated with cancer risk, may be associated with metals exposure. OBJECTIVE To evaluate PON1 activity in relation to cadmium, lead, and mercury levels in healthy, premenopausal women. METHODS Women from upstate New York were followed for ≥ two menstrual cycles. Repeated measures linear mi...

Paraoxonase 1 is known as one of the most important ant oxidative enzymes associated with HDL-c, and because of its antioxidant and antiinflammatory activities. EPA has the antioxidant, anti inflammatory, antithrombogenic, and antiarteriosclerotic properties. Therefore, we investigated the effect of EPA supplementation on the serum levels and activity of PON1 in type 2 diabetic patients. This s...

HDL-associated paraoxonase-1 (PON1) is an enzyme whose activity is associated with cerebrovascular disease. Common PON1 genetic variants have not been consistently associated with cerebrovascular disease. Rare coding variation that likely alters PON1 enzyme function may be more strongly associated with stroke. The National Heart, Lung, and Blood Institute Exome Sequencing Project sequenced the ...