Changes of Mitochondria Copy Number in Association with Idiopathic Pulmonary Fibrosis - Abstract
Background: Idiopathic Pulmonary Fibrosis (IPF) is a fatal lung disease of unknown etiology, where different pathogenetic hypotheses have been suggested. Notwithstanding the unrecognized first trigger that leads to the disease, an imbalance between oxidants and antioxidants seems to accelerate the fibrotic process. The aim of this study was to investigate the mitochondrial DNA (MtDNA) alterations, as oxidative stress marker, in IPF patients in order to explore if it makes sense to carry out an in-depth study with regards to the oxidative stress in IPF, as it plays a key role in the development and progression of this fatal disease.
Methods: 41 IPF patients (age 68.6 ± 5.82; body mass index (BMI) 29.8 ± 2.59) and 20 control subjects (age 66.18 ± 3.72; BMI 27.80 ± 4.64) were enrolled. Patients underwent blood collection. Copy number of MtDNA and nuclear DNA (nDNA) was measured in the blood cells of IPF patients and control subjects by quantitative real-time PCR. The ratio between mitochondrial DNA/nuclear DNA (MtDNA/nDNA) was calculated.
Results: MtDNA/nDNA was significantly higher in IPF patients than in the control group (119.93 ± 79.18 vs 65.97 ± 20.56; p < 0.05). The level of MtDNA/nDNA was negatively
correlated with FVC% (R = -0.5, p < 0.005) and baseline DLCO% (R = -0.35, p < 0.05).
Conclusion: We found an increase of MtDNA/nDNA ratio in IPF subjects that led us to suggest that there is a presence of mitochondrial dysfunction that confirms an important role of the oxidative stress in IPF. Further investigations are required for the prognostic and therapeutic implications that it can have.