Erythropoietin (EPO) inhibits the immunohistochemical expression of lysyl oxidase (LOX) in bleomycin (BLM)-induced pulmonary fibrosis (PF) in rats

AIM:PF is characterized by excessive deposition of collagen and extracellular matrix remodelling.LOX is known for its upregulating role in the fibrotic pathway.EPO is a multiple functional cytokine with anti-inflammatory and anti-apoptotic properties.Aim of this study was to investigate the role of EPO on the expression of LOX in BLM-induced lung fibrosis in rats.METHODS:Fifty Wistar rats (300gr) were divided into five groups of 10 animals each: 1)control animals, 2)intratracheal (i.t) and intraperitoneal (i.p) injection of saline (0.5ml/kg), 3)BLM hydrochloride (7.5mg/kg) i.t injection, 4)BLM hydrochloride (7.5mg/kg) i.t injection followed by EPO i.p injection (2000 iu/kg), 5)saline (0.5ml/kg) i.t injection followed by EPO i.p injection (2000 iu/kg). All rats were sacrificed after 14 days.The expression of LOX was immunohistochemically measured and a scale of four grades (A:0-25%, B:25-50%, C:50-75%, D:75-100%) was used to evaluate it.RESULTS:In groups 1,2 and 5 (control groups), LOX was expressed only in the two lower grades of the scale (A:90% and B:10%).In group 3, LOX was expressed in the high grades (C:20% and D:80%).Finally, in group 4, the enzyme in question was expressed only in the low grades (A:80% and B:20%).The expression of LOX took place in the high grades for group 3 (BLM group) and in the lower grades for group 4 (BLM+EPO group) (p