Serum oxidative-anti-oxidative stress balance is dysregulated in pulmonary hypertensive patients with liver cirrhosis: a case control study

Objective: Hepatopulmonary syndrome (HPS) is characterized by vascular dilatation and hyperdynamic circulation, while portopulmonary hypertension (POPH) is characterized by vasoconstriction with fibrous obliteration of the vascular bed. Vasoactive molecules such as nitric oxide (NO) are candidate factors for cirrhotic complications. However, oxidative stress balance is not well characterized in HPS and POPH. The present objective is to investigate the oxidative stress and anti-oxidative stress balance and NO pathway balance in patients with potential HPS and POPH. Methods: We recruited decompensated cirrhosis patients (69 potential HPS and 61 potential POPH) admitted to our hospital as liver transplantation candidates. Patients exhibiting pO2 lower than 80 mmHg and AaDO2 ≥ 15 mmHg were categorized as potentially having HPS (23/69). Patients exhibiting a tricuspid regurgitation pressure gradient ≥ 25 mmHg were categorized as potentially having POPH (29/61). Serum reactive oxygen metabolites and anti-oxidative OXY-adsorbent tests (OXY) were performed and the balance of these tests was defined as the oxidative index. The correlation between these and clinical characteristics were assessed as a cross-sectional study. Results: Potential HPS patients exhibited no correlation with oxidative stress markers. Potential POPH patients exhibited lower OXY (p=0.037) and higher oxidative index (p=0.001). Additionally, the vascular NO synthase enzyme inhibiting protein asymmetric dimethylarginine