Paraoxonase 3 (PON3)

Paraoxonase 3 is a calcium-dependent glycoprotein enzyme primarily synthesized by the liver and secreted into the bloodstream, tightly bound to HDL particles. Its main functions include **hydrolysis of lactones and oxidative protection of low-density lipoproteins (LDL)**, helping to slow the initiation and progression of atherosclerosis. It also hydrolyzes statin lactones with higher catalytic activity than PON1, which is leveraged as a biochemical marker for measuring PON3 activity. Beyond cardiovascular and metabolic roles, PON3 is upregulated in several cancer types, contributing to tumor cell survival by diminishing mitochondrial oxidative stress and resistance to apoptosis. PON3 plays a defensive role against microbial infection by modulating the inflammation induced by quorum-sensing molecules. Overall, PON3’s activity is integral to multiple processes including oxidative stress modulation, lipid metabolism, and inflammatory signaling, making it a notable target in human disease research.

Other names

Paraoxonase 3PON3Serum paraoxonase/lactonase 3Arylesterase 3Paraoxanase-3PON-3

Hydrolysis of lactone-containing drugs and endogenous compounds. Antioxidant activity: inhibition of LDL oxidation. Modulation of oxidative stress in cardiovascular and neurodegenerative conditions. Protective role against apoptosis in cancer cells, through mitochondrial protection. Modulation of inflammatory responses, especially during bacterial infections.