the factors effect on natural lung surfactant content for the treatment of respiratory distress syndrome

Background: exogenous surfactants from natural sources help restore normal lung function in premature cases. pulmonary-surfactant dysfunction can lead to acute lung injury and is characterized by alveolar instability, floating, and collapse. these abnormalities occur in adult respiratory distress syndrome (ards) and neonatal respiratory distress syndrome (nrds).objectives: this study aimed to identify the best source of exogenous natural surfactant and its composition. methods: twenty-four healthy holstein calves were selected in three age groups in both sexes to investigate the impact of sex and age on the surfactant composition. cell-free bronchoalveolar lavage fluid supernatants were centrifuged at 20000×g for 60 min, allowing separation of crude surfactant pellets. subsequently, the supernatant was discarded, and crude surfactant pellets was separated into several aliquots and stored at -80 ºc for further analysis.results: it was concluded that bronchoalveolar lavage fluid in female groups was significantly enriched by surfactant protein c and surfactant protein d in comparison with male groups at the same age. total phospholipids, glycerides, and cholesterols were not age-dependent in the male groups; however, they had a descending manner associated with age in the female groups.conclusion: age and sex could affect the amount of surface tension that increases with aging, and this trend is lower in the female group compared to the male group. female calves in the younger age group are the best source of natural surfactants required for exogenous surfactant in neonatal respiratory disease due to the highest concentration of dipalmitoylphosphatidylcholin and lowest surface tension.