Sarcoidosis and idiopathic pulmonary fibrosis (IPF) are both associated with deregulated inflammatory mechanisms partially triggered by aggravated oxidative stress. 8-Isoprostane has been proposed as a reliable marker of oxidative stress, linked to several pulmonary diseases. We aimed to explore differences in 8-isoprostane levels in IPF and sarcoidosis patients, and controls.
We included 16 IPF and 55 sarcoidosis patients, as well as 17 controls in the study. 8-Isoprostane levels were measured in serum and in bronchoalveolar lavage (BAL).
Serum 8-isoprostane levels were increased in all patient groups vs controls (p<0.001). The systemic 8-isoprostane concentrations were higher in sarcoidosis patients as compared to IPF subjects and controls (p=0.017 and p<0.001, respectively). IPF patients exhibited increased serum 8-isoprostane levels when compared to controls (p<0.001). Sarcoidosis patients presented significantly increased 8-isoprostane BAL levels when compared to IPF patients (p=0.002).
Our data indicate that the level of oxidative stress, as reflected by 8-isoprostane concentrations, is enhanced in patients with sarcoidosis, and to a lesser extent, in IPF patients when compared to controls, suggesting a potential implication of redox imbalance in both diseases.