Elastin and collagen degradation products in urine of smokers with and without chronic obstructive pulmonary disease.

It has been hypothesized that emphysema results from damage to the elastic fiber network of the lungs as a result of elastase-antielastase imbalance. We used a new assay for urinary desmosine (DES) and isodesmosine (IDES), specific markers for the degradation of mature crosslinked elastin, and hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP), specific markers for the degradation of mature crosslinked collagen, in order to examine elastin and collagen degradation in relation to current cigarette smoking and the presence of chronic obstructive pulmonary disease (COPD). The study sample consisted of 22 never-smokers (NSM group), 13 current smokers without airflow obstruction (SM group), and 21 patients with COPD (COPD group), including both current and former smokers.

Isolation of hydroxylysyl pyridinoline, a mature collagen crosslink from neonatal rat aorta smooth muscle cell cultures.

Hydroxylysyl pyridinoline (HP) is a nonreducible collagen crosslink derived from three posttranslationally modified lysyl residues. Neonatal rat aorta smooth muscle cell cultures (NNRSMC) produce mg amounts of insoluble collagen. The purpose of the present study was to evaluate the capability of NNRSMC to produce collagen containing HP crosslinks.

Alterations of tropoelastin biosynthesis by elastase damage to smooth muscle cell matrices.

The effect of porcine pancreatic elastase (PPE)-induced proteolysis of the extracellular matrix on elastin biosynthesis in neonatal rat aortic smooth muscle cell cultures (NRSMC) was examined. The quantity of insoluble elastin remaining in the damaged cultures decreased with increasing amounts of enzyme used, however no significant cell damage was demonstrated. The accumulation of soluble elastin (tropoelastin) was examined in enzyme injured and control cultures by radiolabelling with [3H]-valine for 4 hours.

Measurement of urinary desmosine by isotope dilution and high performance liquid chromatography. Correlation between elastase-induced air-space enlargement in the hamster and elevation of urinary desmosine.

The accuracy of methods employed to measure the elastin-specific crosslinks, desmosine (DES) and isodesmosine (IDES), has been called into question because contaminants in the urine may cause elevated values. In the present study urine samples were spiked with a known amount of [14C]DES and refluxed in 6 N HCl. Sephadex G-15 chromatography of the hydrolyzed urine employed to remove contaminants.