Comparison of ω-3 fatty acids versus middle/light fatty acids in the intervention of rats model of bleomycininduced pulmonary fibrosis / 中华临床营养杂志

ABSTRACT

ObjectiveTo compare the effectiveness of ω-3 fatty acids and middle/light fatty acids in the intervention of rats model of bleomycin-induced pulmonary fibrosis.MethodsTotally 120 rats were randomly divided into 4 groups normal saline (NS) group,bleomycin-induced pulmonary fibrosis without treatment group ( BLM group),middle/light fatty acids group,ω-3 fatty acids group.Lung tissues were obtained on the 7th,14th,and 21st day after modeling.The left lung were measured by using immunohistochemical methods for transforming growth factor β1 (TGF-β1) and interferon garmma ( IFN-γ).The lower lobe of the right lung underwent HE staining.Serum TGF-β1,IFN-γ,and interleukin-4 (IL-4) were measured using double-antibody sandwich ELISA.ResultsThe pulmonary alveolitis and fibrosis in the ω-3 fatty acids group was significantly milder than in middle/light fatty acids group and BLM group.On the 7th,14th,and 21st day after modeling,stronger TGF-β1 protein expression was detected in the bronehiolar epithelia of middle/light fatty acids group and BLM group and poorer IFN-γexpression in both groups.However,the opposite results were found in the ω-3 fatty acids group on the 7th,14th,and 21st day after modeling,TGF-β1 protein expression ( 13.60 ± 5.90,10.53 ± 4.21,and 7.23 ± 2.21 )was lower ( P =0.047) and IFN-γ ( 13.85 ± 7.48,15.32 ± 2.12,and 18.74 ± 2.65 ) was stronger in ω-3 fatty acids group (P =0.041).On the 7 ,14,and 21st day after modeling,the serum IL-4 levels in the middle/light fatty acids group and BLM group became significantly higher,while the IFN-γ level in both groups was significantly lower than in ω-3 fatty acids group ( P =0.008 ) ; meanwhile,in the ω-3 fatty acids group,the serum IL-4 levels [ (8.73 ± 1.20),(5.73 ±2.03),and (4.98 ± 1.89) pg/ml] were significantly lower (P =0.044) and serum IFN-γlevels [ (5.67 ± 0.13 ),( 6.58 ± 0.64 ),and ( 7.05 ± 0.52 ) pg/ml ] were significantly higher ( P =0.048 ) on the 72,14th,and 21st day after modeling.Conclusionsω-3 fatty acids can lower TGF-β1 protein expression in rat lung tissue and reduce the surum TGF-β1 and IL-4 levels.Compared with the middle/light fatty acids,it can more effectively upregulate the expression of IFN-γ in lung tissue and increase its serum level,and thus alleviate pulmonary fibrosis in rats.