Abstract
The extracellular matrix (ECM) provides strength and elasticity to tissues and plays a key role in regulating cell behavior; damage to this material is believed to be a major factor in many inflammatory diseases. Peroxynitrite/peroxynitrous acid, which is generated at elevated levels at sites of inflammation, is believed to play a role in ECM damage; however, the mechanisms involved are poorly understood. Here we examined the reactions of bolus peroxynitrite, and that generated in a time-dependent manner by SIN-1 decomposition, with ECM isolated from a vascular smooth muscle cell line and porcine thoracic aorta. Bolus peroxynitrite caused the release of ECM glycosaminoglycans and proteins, the formation of 3-nitroTyr, and the detection of ECM-derived radicals (by immuno-spin trapping) in a concentration-dependent manner. Release and nitration of ECM components were modulated by the local pH and bicarbonate. SIN-1 caused the release of glycosaminoglycan, but not protein, from vascular smooth muscle cell-derived ECM in a concentration-, time-, and pH-dependent manner. The data presented here suggest that peroxynitrite-mediated damage to ECM occurs via a radical-mediated pathway. These reactions may contribute to ECM damage at sites of inflammation and play a role in disease progression, including rupture of atherosclerotic lesions.
| Original language | English |
|---|---|
| Journal | Free Radical Biology & Medicine |
| Volume | 45 |
| Issue number | 5 |
| Pages (from-to) | 716-25 |
| Number of pages | 10 |
| ISSN | 0891-5849 |
| DOIs | |
| Publication status | Published - 1 Sept 2008 |
| Externally published | Yes |
Keywords
- Animals
- Bicarbonates
- Cells, Cultured
- Extracellular Matrix
- Hydrogen-Ion Concentration
- Molecular Structure
- Molsidomine
- Muscle, Smooth, Vascular
- Myocytes, Smooth Muscle
- Peroxynitrous Acid
- Rats
- Swine
- Tyrosine