Comparative study on gene expression profile in rat lung after repeated exposure to diesel and biodiesel exhausts upstream and downstream of a particle filter. (November 2020)

• Record Type: Journal Article
• Authors: Lecureur, Valérie; Monteil, Christelle; Jaguin, Marie; Cazier, Fabrice; Preterre, David; Corbière, Cécile; Gosset, Pierre; Douki, Thierry; Sichel, François; Fardel, Olivier
• Is Part Of: Environmental pollution. Volume 266:Part 2(2020)
• Publication Date: 2020-11
• Subjects: Biodiesel -- Diesel exhaust -- Lung -- Particle filter -- Transcriptome analysis; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2020.115264
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Biodiesel is considered as a valuable and less toxic alternative to diesel. However, cellular and molecular effects of repeated exposure to biodiesel emissions from a recent engine equipped with a diesel particle filter (DPF) remain to be characterized. To gain insights about this point, the lung transcriptional signatures were analyzed for rats (n = 6 per group) exposed to filtered air, 30% rapeseed biodiesel (B30) blend or reference diesel (RF0), upstream and downstream a DPF, for 3 weeks (3 h/day, 5 days/week). Genomic analysis revealed a modest regulation of gene expression level (lower than a 2-fold) by both fuels and a higher number of genes regulated downstream the DPF than upstream, in response to either RF0 or to B30 exhaust emissions. The presence of DPF was found to notably impact the lung gene signature of rats exposed to B30. The number of genes regulated in common by both fuels was low, which is likely due to differences in concentrations of regulated pollutants in exhausts, notably for compound organic volatiles, polycyclic aromatic hydrocarbons, NO or NOx. Nevertheless, we have identified some pathways that were activated for both exhaust emissions, such as integrin-, IGF-1- and Rac-signaling pathways, likely reflecting the effects of gas phase products. By contrast, some canonical pathways relative to "oxidative phosphorylation" and "mitochondrial dysfunction" appear as specific to B30 exhaust emission; the repression of transcripts of mitochondrial respiratory chain in lung of rats exposed to B30 downstream of DPF supports the perturbation of mitochondria function. This study done with a recent diesel engine (compliant with the European IV emission standard) and commercially-available fuels reveals that the diesel blend composition and the presence of an after treatment system may modify lung gene signature of rats repeatedly exposed to exhaust emissions, however in a rather modest manner. Graphical abstract: Image 1 Highlights: Repeated lung exposures to diesel or biodiesel induce low level expression of genes. Exposure to diesel or biodiesel induces a different profile of gene expression. Diesel particle filter modifies exhaust composition and gene expression profile. Mitochondrial dysfunction is observed downstream the diesel particle filter. Abstract : The lung gene signatures of rat exposed repeatedly to diesel and biodiesel vary with the diesel composition, the presence of a diesel particle filter and support modest lung adverse effects.