The effects of omega-3 fatty acids on the newborn rat hyperoxic lung injury

Objective: Bronchopulmonary dysplasia (BPD) is an important cause of morbidity in preterms. Inflammation plays a central role in the pathogenesis of the disease while omega-3 fatty acids are known to have anti-inflammatory effects. In this study, we examined the effects of supplementary omega-3 fatty acids on hyperoxic lung injury. Methods: Experimental hyperoxic lung injury induced newborn 3-day-old rats were monitored in a confined hyperoxic environment with an oxygen concentration of 90-95% for a 2-week period. Rats were divided into three groups as placebo, low-dose Omega-3, and high-dose Omega-3. During the 2-week study period, low and high-dose Omega-3 groups were given 300 and 600 mg/kg/day omega-3 docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) respectively, while those in placebo received the same amount of serum physiologic. At the end of the 2-week study, lungs of all the rats were removed and morphologic evaluation under light microscopy was performed. Mean cord length (L-m), alveolar surface area (S-A), and alveolar wall thickness (W-t) were calculated to find out whether a statistically significant difference between groups existed. Results: Similar alveolar development was observed between groups. No difference was seen between mean L-m values. Although the alveolar surface area was found to be higher in high-dose omega-3 group, the difference was not considered to be statistically significant. While the widest alveolar wall thickness was observed in the placebo group, alveolar wall thickness difference between high-dose omega-3 group and placebo group was found to be statistically significant (placebo W-t=17,8 +/- 2.3 mu m, low-dose omega -3 W-t=15,6 +/- 2,5 mu m, high-dose omega -3 W-t=14,2 +/- 2 mu m) (p < .05). Conclusions: Omega-3 fatty acids were observed to prevent alveolar wall thickness to some extent, though with no noticeable effect on hyperoxic lung injury.