Enzymes
Product List
PON1 Human
Paraoxonase-1 Human Recombinant
PON1 Human, HEK
Paraoxonase-1 Human Recombinant, HEK
HEK293 Cells.
PON2 Human
Paraoxonase-2 Human Recombinant
Introduction
Paraoxonases are a family of mammalian enzymes with aryldialkylphosphatase activity. There are three known paraoxonase isozymes: PON1, PON2, and PON3. These enzymes were initially identified for their role in hydrolyzing organophosphates, such as those found in insecticides . The genes encoding these enzymes are located on the long arm of chromosome 7 in humans .
Key Biological Properties: Paraoxonases exhibit esterase and lactonase activities, with a broad substrate specificity . They are involved in hydrolyzing a variety of substrates, including lactones and aryl esters .
Expression Patterns: PON1 is primarily expressed in the liver but is also found in the kidney and colon . PON2 is ubiquitously expressed in various tissues, including the brain, lungs, and small intestine . PON3 is expressed in the liver and associated with high-density lipoprotein (HDL) in the bloodstream .
Tissue Distribution: PON1 is synthesized in the liver and transported into the bloodstream, where it associates with HDL . PON2 is found in many tissues, including the brain, lungs, heart, and liver . PON3 is present in HDL, mitochondria, and the endoplasmic reticulum .
Primary Biological Functions: Paraoxonases play crucial roles in protecting against oxidative stress, inflammation, and atherosclerosis . They exhibit anti-inflammatory, anti-oxidative, anti-atherogenic, anti-diabetic, anti-microbial, and organophosphate-hydrolyzing properties .
Role in Immune Responses and Pathogen Recognition: Paraoxonases, particularly PON1, are involved in the innate immune system by hydrolyzing toxic metabolites and preventing oxidative damage . PON2 has been shown to protect against bacterial infections due to its high expression in human keratinocytes .
Mechanisms with Other Molecules and Cells: Paraoxonases interact with various molecules and cells through their enzymatic activities. PON1, for example, hydrolyzes lactones and aryl esters, utilizing a catalytic calcium ion to stabilize substrate and reaction states .
Binding Partners and Downstream Signaling Cascades: PON1 associates with HDL in the bloodstream, contributing to its antioxidant properties by preventing the oxidation of low-density lipoproteins (LDL) . PON2 and PON3 also exhibit lactonase activity, which is crucial for their protective roles against oxidative stress .
Regulatory Mechanisms Controlling Expression and Activity: The expression and activity of paraoxonases are regulated at multiple levels, including transcriptional regulation and post-translational modifications . Factors such as oxidative stress, inflammation, and genetic polymorphisms can influence paraoxonase activity .
Transcriptional Regulation and Post-Translational Modifications: Transcriptional regulation of paraoxonase genes involves various transcription factors and regulatory elements. Post-translational modifications, such as phosphorylation and glycosylation, can also modulate enzyme activity .
Biomedical Research: Paraoxonases are studied for their roles in cardiovascular diseases, diabetes, and neurodegenerative disorders . Their antioxidant and anti-inflammatory properties make them potential targets for therapeutic interventions .
Diagnostic Tools: PON1 activity is used as a biomarker for oxidative stress and cardiovascular diseases . Measuring paraoxonase activity can help in diagnosing and monitoring these conditions .
Therapeutic Strategies: Enhancing paraoxonase activity through drugs, nutrients, and plant extracts is being explored as a therapeutic strategy to prevent and treat diseases associated with oxidative stress and inflammation .
Role Throughout the Life Cycle: Paraoxonases play essential roles from development to aging and disease. During development, they protect against oxidative stress and inflammation . In aging, decreased paraoxonase activity is associated with increased susceptibility to diseases such as atherosclerosis and neurodegeneration .
From Development to Aging and Disease: Paraoxonases contribute to maintaining cellular homeostasis and protecting against environmental toxins throughout the life cycle . Their roles in various diseases highlight their importance in health and disease management .
