Impact of quercetin on pulmonary toxicity induced by diesel exhaust nanoparticles in albino rat : Histological, immunohistochemical and biochemical study

Abstract

Background: Diesel exhaust nanoparticles (DENPs) are one of the most prevalent environmental pollutants that adverselyaffect human health. DENPs are involved in the occurrence of chronic lung diseases such as COPD, bronchial asthma, chronicbronchitis and cancer.Objective: Evaluation of DENPs damaging effects on the pulmonary tissue and assessment of the possible protective effectsof Quercetin (QRT) on the lung tissue via histological, immunohistochemical and biochemical assessment.Materials and Methods: Forty-five albino male rats were divided into 3 groups: Group I (control rats), Group II (DENPsgroup) received repeated doses of DENPs (180μg/rat) intratracheally every other day for 6 days, Group III (DENPs + QRT)received quercetin orally (60 mg/kg B.Wt.) 1h before DENPs exposure. Examination of Lung tissues were conductedbyhistological and immunohistochemical techniques. Assessment of certain oxidative stress markers were also conducted.Results: Group II showedsignificant changes in the histological picture of the lung tissue with collapsed alveoli, thickinteralveolar septa and marked cellular infiltration. Collagen fibers were markedly increased by DENPs. Quercetin treatmentled to amelioration of the histological findings in the lung tissue with marked decrease in collagen fibers. QRT led to significantdecrease in iNOS immunoreactivity and increase in PCNA immunoreactivity.Conclusion: Quercetin has protective effects against pulmonary toxicity induced by DENPs via its anti-inflammatory effectsand anti-oxidant properties.