Investigation of the effects of hydroxychloroquine on rats with pulmonary contusion caused by blunt thoracic trauma.

PURPOSE: To investigate the early and late effects of hydroxychloroquine (HCQ) on inflammation, fibrosis, and apoptosis in an experimental rat model of pulmonary contusion. METHODS: Thirty-five male Wistar albino rats were randomly allocated into five groups (n = 7): control, pulmonary contusion evaluated on day 3 or day 10 (PC-3 and PC-10), and pulmonary contusion treated with HCQ at 100 mg/kg/day by gavage and evaluated on day 3 or day 10 (PCHCQ-3 and PCHCQ-10). Lung injury was assessed histopathologically by alveolar edema, congestion, leukocyte infiltration, and fibrosis scores and immunohistochemically by caspase-3, inducible nitric oxide synthase (iNOS), and endothelial nitric oxide synthase (eNOS) expression. RESULTS: No alveolar edema was observed. Congestion and leukocyte infiltration were significantly greater in all contusion groups than in the control group. Fibrotic changes were detected on day 10 in both treated and untreated contusion groups. Caspase-3 and iNOS expression were significantly higher in the contusion groups than in the control group. HCQ did not significantly reduce leukocyte infiltration, fibrosis, apoptosis, or iNOS expression compared with the corresponding untreated groups. CONCLUSION: HCQ administered at 100 mg/kg/day for three or 10 days did not demonstrate significant anti-inflammatory, anti-apoptotic, or antifibrotic effects in this rat model of pulmonary contusion.