Abstract. The aim of this study was to evaluate the therapeutic effect of lycopene on a hyperoxia-induced lung injury model in rat pups. Full-term rat pups were included in the study 12–24 h after delivery. The pups were separated into 4 groups: normoxia control (NC), hyperoxia control (HC), hyperoxia + lycopene (HL), and normoxia lycopene (NL). The normoxia groups were housed in ambient air, and the hyperoxia groups in > 85% O2. HL and NL groups received 50 mg lycopene in oil/kg body weight/day delivered intraperitoneally (i.p.), the other groups received oil alone. On day 11, the rat pups were sacrificed and their lungs removed. Statistically significant injury was observed in all histological parameters measured (MLI, proliferating cell nuclear antigen (PCNA), and apoptosis) in the HC group (HC vs NC, p = 0.001). This injury could not be reversed with lycopene treatment (HC vs HL, 0.05; NC vs HL, p = 0.001). With hyperoxia, statistically significant decreases were observed in biochemical parameters in terms of SOD, MDA, and IL-6 values (HC vs NC: SOD, p = 0.02; MDA, p = 0.043; IL-6, p = 0.001). The use of lycopene did not provide any improvement in these values (HC vs HL, p > 0.05). Hyperoxia or lycopene had no effect on IL-1β and GPx (p > 0.05). When comparing NC and NL groups, negative effects were observed in the group given lycopene in terms of MLI, PCNA, apoptosis, and IL-6 (all parameters, p = 0.001). We observed that 50 mg lycopene in oil/kg body weight/day given via i.p. had no curative effect on the hyperoxia-induced lung injury in newborn rats and may even induce adverse effects.
Nitric oxide synthase inhibition decreases tolerance to hyperoxia in newborn rats