Pulmonary fibrosis is a major health problem. Paraquat (PQ) is a highly toxic herbicide. Bone marrow mesenchymal stem cells (BMSCs) represent a promising tool for the treatment of fatal pulmonary fibrosis.
Aim of the work
The aim of the study was to investigate the effect of BMSC transplantation in an experimental model of lung fibrosis induced by PQ.
Materials and methods
Forty male albino rats were classified into four equal groups. Group I was the control group. Group II comprised rats that received a single intraperitoneal injection of 15 mg/kg PQ and were sacrificed 14 days later. Group III was subdivided into subgroup IIIa, which comprised rats that received BMSCs 6 h after PQ injection and were sacrificed 14 days later, and subgroup IIIb, which comprised rats that received BMSCs 14 days after PQ injection and were sacrificed 28 days later. Group IV comprised rats that received PQ injection similar to group II and were sacrificed 28 days later. Lung specimens were processed for histological and immunohistochemical studies.
In groups II and IV, there was diffuse thickening of the interalveolar septa by heavy mononuclear cellular infiltration, together with desquamation of the bronchiolar epithelial lining. Significant deposition of collagen fibers was also detected, which led to narrowing of most of the alveolar lumen. In group III, BMSCs resulted in attenuation of most of the lung injury. Significant reduction in the area% of collagen fibers, together with significant increase in pan-cytokeratin immunoexpression, was detected. Meanwhile, subgroup IIIa showed better histological results compared with subgroup IIIb.
Early administration of BMSCs led to marked improvement in PQ-induced lung fibrosis.