A histological and immunohistochemical study of the possible protective effect of N-acetyl cysteine on experimentally induced acute lung injury in adult male albino rats

Background N-acetyl cysteine (NAC) has mucolytic effects. It stimulates glutathione biosynthesis, which is a powerful antioxidant. Cyclophosphamide (CP) is a synthetic alkylating agent utilized in the management of autoimmune illnesses and cancer; it can induce lung toxicity through damage to mitochondria. Aim To examine the probable protective effect of NAC on experimentally induced acute lung injury in adult male albino rats by using various histological and immunohistochemical methods. Materials and methods Forty-five adult male albino rats have been utilized in this research. Group I was the control, group II received NAC at a dose of 200 mg/kg/day for 15 days, group III received a single dose of CP at a dose of 200 mg/kg, and group IV received 200 mg/kg/day of NAC for 1 week then intraperitoneal injection of 200 mg/kg of CP on the 8th day then NAC for another 1 week. Lung sections have been stained using hematoxylin and eosin, special stains, and various immunohistochemical stains. Morphometric study and statistical analysis have been carried out. Results Sections of group III illustrated some histological anomalies in the form of narrowing of some alveoli and dilatation of others, in addition to thickening of the interalveolar septa. Interstitial tissue showed heavy inflammatory infiltration and dilated, congested blood vessels. Detachment of the lining epithelium of bronchioles was observed. These changes were improved in group IV. Conclusion CP induces changes in lung tissue that can be ameliorated by NAC.