ALVEOLAR STRUCTURE, GAS EXCHANGE PHYSIOLOGY, AND OXIDATIVE STRESS BIOCHEMISTRY IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE: AN ANALYTICAL CROSS-SECTIONAL STUDY
Main Article Content
Keywords
Chronic obstructive pulmonary disease, oxidative stress, gas exchange, emphysema, spirometry, antioxidants
Abstract
Background: Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disorder characterized by persistent airflow limitation, alveolar destruction, and impaired gas exchange. Oxidative stress is increasingly recognized as an important contributor to COPD pathogenesis; however, the combined relationship among structural, physiological, and biomarker-based parameters has not been adequately explored.
Objective: To evaluate the relationship between alveolar structural changes, gas exchange physiology, and oxidative stress biomarkers in patients with COPD.
Methods: The study was an analytical cross-sectional design carried out in Prime College of Allied Health Sciences, Peshawar, Pakistan between January 2024 and January 2025. A total of 72 patients with COPD were selected through consecutive non-probability sampling. Pulmonary function was assessed using spirometry, including forced expiratory volume in one second, forced vital capacity, and the forced expiratory volume in one second/forced vital capacity ratio. Disease severity was classified according to the Global Initiative for Chronic Obstructive Lung Disease criteria. Gas exchange was evaluated using arterial blood gas analysis and diffusing capacity of the lungs for carbon monoxide. Alveolar structural changes were assessed using computed tomography-based emphysema scoring. Oxidative stress biomarkers, including malondialdehyde, reactive oxygen species, and nitric oxide, along with antioxidant markers including superoxide dismutase, glutathione, and catalase, were measured. Data were analyzed using IBM SPSS Statistics version 25. Continuous variables were presented as mean ± standard deviation, whereas categorical variables were reported as frequencies and percentages. Pearson correlation analysis was used to examine relationships among oxidative stress biomarkers, pulmonary function, and gas exchange parameters. A p-value of ≤0.05 was considered statistically significant
Results: The mean age of the participants was 58.4 ± 9.6 years, with a predominance of male patients (72.2%). Significant airflow limitation was observed, as indicated by a reduced Forced Expiratory Volume in one second (FEV₁) of 52.6 ± 14.2%. Gas exchange impairment was evident from decreased partial pressure of oxygen in arterial blood (PaO₂) and reduced diffusing capacity of the lungs for carbon monoxide (DLCO). Markers of oxidative stress were significantly elevated, whereas antioxidant levels were reduced. A strong negative correlation was found between malondialdehyde (MDA) and Forced Expiratory Volume in one second (FEV₁) (r = -0.62, p < 0.001). Structural lung damage also showed a significant association with impaired gas exchange and increased oxidative stress
Conclusion: COPD is a multifactorial disease involving structural destruction, physiological impairment, and biochemical imbalance. Oxidative stress is strongly associated with disease severity and may serve as a potential biomarker for progression. A multidimensional assessment approach is recommended for improved disease evaluation and management.
References
2. Bezerra, F.S., et al., Oxidative stress and inflammation in acute and chronic lung injuries. 2023. 12(3): p. 548.
3. Nucera, F., et al., Role of oxidative stress in the pathogenesis of COPD. 2022.
4. Sierra-Vargas, M.P., et al., Oxidative stress and air pollution: its impact on chronic respiratory diseases. 2023. 24(1): p. 853.
5. Rodrigues, S.d.O., et al., Mechanisms, pathophysiology and currently proposed treatments of chronic obstructive pulmonary disease. 2021. 14(10): p. 979.
6. Di Stefano, A., et al., Oxidative and nitrosative stress in the pathogenesis of obstructive lung diseases of increasing severity. 2020. 27(42): p. 7149-7158.
7. Xu, Y., H. Liu, and L.J.J.o.n. Song, Novel drug delivery systems targeting oxidative stress in chronic obstructive pulmonary disease: a review. 2020. 18(1): p. 145.
8. Kotlyarov, S.J.I.j.o.m.s., The role of smoking in the mechanisms of development of chronic obstructive pulmonary disease and atherosclerosis. 2023. 24(10): p. 8725.
9. Pingle, S., et al., Goblet, club and alveolar cells: front-line defenders of the airways in chronic obstructive pulmonary disease, a most common lung disease in miners, in Medical geology in mining: health hazards due to metal toxicity. 2022, Springer. p. 83-100.
10. Cho, S.J. and H.W.J.A.r.o.p. Stout-Delgado, Aging and lung disease. 2020. 82(1): p. 433-459.
11. Finicelli, M., et al., The emerging role of macrophages in chronic obstructive pulmonary disease: the potential impact of oxidative stress and extracellular vesicle on macrophage polarization and function. 2022. 11(3): p. 464.
12. Lee, J., et al., An update on the role of Nrf2 in respiratory disease: molecular mechanisms and therapeutic approaches. 2021. 22(16): p. 8406.
13. Liu, H., et al., Targeting biophysical microenvironment for improved treatment of chronic obstructive pulmonary disease. 2023. 29(11): p. 926-938.
14. Alwazeer, D., et al., Combating oxidative stress and inflammation in COVID‐19 by molecular hydrogen therapy: mechanisms and perspectives. 2021. 2021(1): p. 5513868.
15. Aghapour, M., et al., Mitochondria: at the crossroads of regulating lung epithelial cell function in chronic obstructive pulmonary disease. 2020. 318(1): p. L149-L164.
16. Cao, Y., et al., Diaphragm dysfunction and rehabilitation strategy in patients with chronic obstructive pulmonary disease. 2022. 13: p. 872277.
17. Cha, S.-R., et al., Cigarette smoke-induced respiratory response: insights into cellular processes and biomarkers. 2023. 12(6): p. 1210.
18. Zhang, S., et al., Glutamine inhibits inflammation, oxidative stress, and apoptosis and ameliorates hyperoxic lung injury. 2023. 79(3): p. 613-623.
19. Ruaro, B., et al., The history and mystery of alveolar epithelial type II cells: focus on their physiologic and pathologic role in lung. 2021. 22(5): p. 2566.
20. Rajabi, H., et al., Emerging role of exosomes in the pathology of chronic obstructive pulmonary diseases; destructive and therapeutic properties. 2022. 13(1): p. 144.
21. Easter, M., et al., Targeting aging pathways in chronic obstructive pulmonary disease. 2020. 21(18): p. 6924.
22. Karnati, S., et al., Chronic obstructive pulmonary disease and the cardiovascular system: vascular repair and regeneration as a therapeutic target. 2021. 8: p. 649512.
Article Sidebar
Article Details
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
All articles published in JPTCP are licensed under Copyright Creative Commons Attribution-NonCommercial 4.0 International License.
Maryum Saeed Hashmi
Lecturer, Department of Basic Sciences, Prime College of Allied Health Sciences, Peshawar, Pakistan
Khurram Munir
Assistant Professor, Department of Physiology, Sheikh Zayed Medical College, Rahim Yar Khan, Pakistan
Afshan Iftikhar
Assistant Professor, Department of Physiology, Rehman Medical College, Peshawar, Pakistan
Javaid Hassan
Associate Professor, Department of Physiology, Kabir Medical College, Gandahara University, Peshawar, Pakistan
Mohammad Iqbal S
Assistant Professor, Department of Biochemistry, Muhammad College of Medicine Peshawar, Pakistan
Saima Roedar
Senior Lecturer, Department of Basic Sciences, Prime College of Allied Health Sciences, Peshawar, Pakistan
