Melatonin effects on pulmonary tissue in the experimental model of Hepatopulmonary Syndrome

Abstract

Objective: To evaluate the pulmonary alterations of animals with Hepatopulmonary Syndrome (HPS) submitted to Biliary Duct Ligature (BDL), as well as the antioxidant effect of Melatonin (MEL). Methods: Sixteen male Wistar rats, divided into four Sham groups: BDL group, Sham + MEL group and BDL + MEL. The pulmonary and hepatic histology, lipoperoxidation and antioxidant activity of lung tissue, alveolar-arterial O2 difference and lung / body weight ratio (%) were evaluated. Results: When comparing the groups, could be observed an increase of vasodilation and pulmonary fibrosis in the BDL group and the reduction of this in relation to the BDL + MEL group. It was also observed significant changes in the activity of catalase, ApCO2, ApO2 in the LBD group when compared to the other groups. Conclusion: The use of MEL has been shown to be effective in reducing vasodilation, fibrosis levels and oxidative stress as well as gas exchange in an experimental HPS model.

Beneficial effects of melatonin on liver fibrosis: A systematic review of current biological evidence

“…Most articles included in this systematic review have reported the antioxidant and anti‐inflammatory actions of melatonin as part of its antifibrotic effects. Similarly, several investigations carried out with different hepatic disease models have also reported antioxidant properties of melatonin directly related to its positive activity on abrogating NAFLD and hepatic ischemic injury, among others (Bosco et al, 2019; Joshi et al, 2021; H. W. Li et al, 2021). Together with oxidative stress, inflammation is a process highly associated with hepatic damage (Mortezaee & Khanlarkhani, 2018), where melatonin has also been demonstrated to modulate the inflammatory response in several liver pathologies by restraining an overactivated response derived from chronic liver injury (Laliena et al, 2012; H. W. Li et al, 2021) or even from hepatotoxicity (Yang et al, 2021).…”

Lungs as target of COVID-19 infection: Protective common molecular mechanisms of vitamin D and melatonin as a new potential synergistic treatment

“…By removing free radicals, melatonin may adequately modulate autophagy pathways and apoptosis, which are key mechanism in the development of idiopathic pulmonary fibrosis [58]. Additionally, the utilization of melatonin in the treatment of animals with induced hepatopulmonary syndrome was effective in the reduction of lung fibrosis levels, vasodilation, and oxidative stress [59].…”

Pineal hormone melatonin as an adjuvant treatment for COVID‑19 (Review)

“…Melatonin has been hypothesized to remove free radicals, and therefore may modulate autophagy pathways and apoptosis, which are critical factors in the development of idiopathic pulmonary fibrosis ( 10 ). In addition, the use of melatonin in animals (rats and rabbits), with induced hepatopulmonary syndrome, has been proven to be beneficial in the reduction of lung fibrosis levels, oxidative stress and vasodilation ( 45 ).…”