desmosine and Idiopathic-Pulmonary-Fibrosis

Although chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF) seem to be opposite entities from a clinical perspective, common initial pathogenic steps have been suggested in both lung diseases. Emphysema is caused by an elastase/anti-elastase imbalance leading to accelerated elastin degradation. Elastinolysis is however, also accelerated in the IPF patients' lungs. The amino acids desmosine and isodesmosine (DES) are unique to elastin. During the degradation process, elastases liberate DES from elastin fibers. Blood DES levels consequently reflect the rate of systemic elastinolysis and are increased in COPD. This is the first report describing elevated DES levels in IPF patients. We also demonstrated that the age-related increment of DES concentrations is enhanced in IPF. Our current study suggests that elastinolysis is a shared pathogenic step in both COPD and IPF. Further investigation is required to establish the relevance of accelerated elastin degradation in IPF and to determine whether decelerating this process leads to slower progression of lung fibrosis and better survival for patients with IPF.

Topics: Aged; Aging; Biomarkers; Desmosine; Elastin; Female; Humans; Idiopathic Pulmonary Fibrosis; Male; Middle Aged; Pulmonary Disease, Chronic Obstructive

Pleuroparenchymal fibroelastosis (PPFE) is a rare interstitial pneumonia with upper lobe predominance and fibroelastosis. Although definite diagnosis requires surgical lung biopsy (SLB), SLB is often difficult because of its complications such as refractory pneumothorax.. To evaluate urinary desmosines (degradation product of mature elastin) as a novel biomarker in patients with PPFE.. Biopsy-proven patients with PPFE (n = 14) were prospectively enrolled. Levels of urinary desmosines in patients with PPFE were measured with liquid chromatography-tandem mass spectrometry (LC-MS/MS) and compared with those in patients with idiopathic pulmonary fibrosis (IPF), patients with chronic obstructive pulmonary disease (COPD), and controls.. Levels of urinary desmosines were significantly higher in patients with PPFE than those in patients with IPF (48.4 vs. 28.6 ng/mg creatinine, p = 0.034), patients with COPD (8.0 ng/mg creatinine, p < 0.001), or controls (17.4 ng/mg creatinine, p < 0.001). Desmosines discriminated between PPFE and IPF (area under the curve [AUC] = 0.708), and between PPFE and controls (AUC = 0.956). However, levels of desmosines were not correlated with physiological parameters in patients with PPFE.. Urinary desmosines may be a useful diagnostic biomarker in patients with PPFE. Measurement of desmosines combined with specific clinical and radiological features of PPFE may lead to an accurate diagnosis without SLB in patients with PPFE.

Topics: Aged; Biomarkers; Biopsy; Desmosine; Diagnosis, Differential; Elastic Tissue; Female; Fibrosis; Humans; Idiopathic Pulmonary Fibrosis; Lung; Lung Diseases, Interstitial; Male; Middle Aged; Prospective Studies; Pulmonary Disease, Chronic Obstructive; ROC Curve; Tandem Mass Spectrometry; Tomography, X-Ray Computed