Myeloperoxidase as an Active Disease Biomarker: Recent Biochemical and Pathological Perspectives

Area of Science:

• Biochemistry
• Immunology
• Molecular Biology

Background:

• Myeloperoxidase (MPO) is a heme-containing enzyme produced by polymorphonuclear neutrophils.
• The active MPO enzyme is a homodimer formed after several post-translational modifications of the primary gene product.
• MPO utilizes hydrogen peroxide to generate hypohalous acids, playing a crucial role in host defense.

Purpose of the Study:

• To elucidate the structure, function, and clinical significance of Myeloperoxidase.
• To highlight the role of MPO in both host defense and the pathogenesis of chronic diseases.
• To establish MPO as a diagnostic biomarker for inflammatory and oxidative stress conditions.

Main Methods:

• Analysis of MPO gene expression and protein modifications.
• Investigation of MPO's enzymatic activity in generating reactive oxygen and nitrogen species.
• Correlation of MPO levels with inflammatory responses and disease pathogenesis.

Main Results:

• MPO undergoes complex processing from its gene product to an active homodimeric enzyme.
• MPO's antibacterial function relies on the production of hypohalous acids and other reactive species.
• Uncontrolled MPO release contributes to tissue damage and is implicated in diseases like rheumatoid arthritis, cardiovascular diseases, diabetes, and cancer.

Conclusions:

• Myeloperoxidase is a critical enzyme in innate immunity with a dual role in host defense and disease.
• MPO-derived oxidants are implicated in the pathogenesis of numerous chronic inflammatory conditions.
• Elevated MPO activity serves as a valuable diagnostic biomarker for inflammatory and oxidative stress states.