lysyylioksidaasin

Lysyylioksidaasi (LOX) is a copper-dependent amine oxidase that catalyzes the oxidative deamination of lysine and hydroxylysine residues in extracellular matrix proteins. This enzymatic activity is crucial for the formation of covalent cross-links between collagen and elastin molecules, a process known as fibrillogenesis. These cross-links are essential for the structural integrity, tensile strength, and mechanical properties of connective tissues.

There are several isoforms of lysyylioksidaasi, with LOX and LOXL being the most well-studied. LOX is primarily responsible for cross-linking collagen, while the LOXL family members (LOXL1-LOXL4) exhibit broader substrate specificity and are involved in the cross-linking of both collagen and elastin, as well as other proteins. The activity of lysyylioksidaasi is tightly regulated, and dysregulation of its expression or activity has been implicated in various physiological and pathological conditions.

In normal tissue development and repair, lysyylioksidaasi plays a vital role in maintaining tissue homeostasis. However, aberrant LOX activity is associated with diseases such as fibrosis, cancer, and cardiovascular disorders. In cancer, increased LOX expression can promote tumor growth, invasion, and metastasis by remodeling the tumor microenvironment and enhancing cell migration. Conversely, inhibiting LOX activity has been explored as a therapeutic strategy to counteract these effects. The enzyme's involvement in extracellular matrix deposition and modification also makes it a target for understanding and treating conditions related to aging and tissue degeneration.