Effect of Losartan drug on pulmonary fibrosis induced by Bleomycin in experimental rats

The present study investigated the protective effect of losartan (Angiotensin 11 inhibitor AT1) administration against bleomycin-induced pulmonary fibrosis in adult male rats. A total of 40 male adult albino rats (Rattus norvegicous) weighing from 200-300 gm each, were divided into four groups of (10) animals each. The first group received a daily intraperitonial (i.p) injection of vehicle normal saline (0.5ml\animal, daily to end experiment), and served as control group. Animals in the second, third and fourth groups were administrated i.p. with bleomycin (15mg\kg\3times weekly for 3 wks), losartan (50mg\kg orally daily to end experiment) and losartan a combination with bleomycin simultaneously to end experiment, respectively. The present study, declared that the biochemical results determined the levels of Superoxide dismutase (SOD), Glutathion peroxidase (GSHpx) and Hydroxyproline(HYP) content in blood serum of animals. Where after oral administration of losartan in combination with bleomycin, showed that losartan significantly increase SOD P˂0.008 and GSHpx P˂0.001 levels, and decreased HYP P˂0.001 contents in blood stream of the rats in comparison with bleomycin group. conversely, study showed After intraperitonial injection of bleomycin alone, decreased level of SOD, GSHpx and increased of HYP content in blood serum of rats in comparison of control group. On the other hand, microscopical observations clarified that bleomycin injection showed that inflammatory cells infiltration and fibrotic scores were more prominent, in addition to that, atelected alveoli with damage to lung architecture as well as collagens deposition around patches of alveoli and peribronchioles in the model group compared to the control group, oral administration of losartan in combination with bleomycin, showed marked attenuated the severity of bleomycin -induced pulmonary fibrosis, where identified by reduce the inflammatory cells infiltration whether intraaleveolar or interalveolar septa. This investigation has clearly identified the importance role of losartan as inhibitor factor on pulmonary fibrosis induced by blm, therefore the findings may be offer one of therapeutic strategy to prevent the lung fibrosis in experimental model.