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Atmospheric fine particulate matter exposure (PM 2.5) can increase the incidence and mortality of heart disease, and raise the risk of fetal congenital heart defect, which have recently drawn much attention. In this study, C57BL/6 mice were exposed to PM 2.5 (approximately equivalent to 174 μg/m3) by intratracheal instillation during the gestation. After birth, 10 weeks old offspring mice were divided into four groups: male exposed group (ME), female exposed group (FE), male control group (MC), female control group (FC). The pathological injury, pro-inflammatory cytokines, histone acetylation levels, and expressions of GATA-binding protein 4 (GATA4) and downstream genes were investigated. The results showed that exposure to PM 2.5 in utero increased pathological damage and TNF-α and IL-6 levels in hearts of offspring mice, and effects in ME were more serious than FE. Notably, GATA4 protein levels in hearts in ME were significantly lower than that of MC, accompanied by down-regulation of histone acetyltransferase (HAT)-p300 and up-regulation of histone deacetylase-SIRT3. As GATA4 downstream genes, ratios of β-MHC gene expression to α-MHC significantly raised in ME relative to the MC. Results of chromatin immunoprecipitation (ChIP)-qPCR assay found that binding levels of acetylated histone 3 lysine 9 (H3K9ac) in GATA4 promoter region in the hearts of ME or FE were markedly decreased compared with their corresponding control groups. It suggested that maternal exposure to PM 2.5 may cause cardiac injury in the offspring, heart damage of male mice was worse than female mice, in which process HAT-p300, H3K9ac, transcription factor GATA4 may play an important regulation role. Image 1 • PM 2.5 exposure in utero caused heart injury and inflammation in offspring mice. • GATA4 expression decline along with p300 down-regulation and SIRT3 up-regulation. • Binding levels of H3K9ac in GATA4 promoter region were related to GATA4 expression. • Gender differences of mouse heart damage after PM 2.5 exposure in utero exist. [ABSTRACT FROM AUTHOR]

Particulate matter (PM) exposure increases the risk of asthma. However, the effect of PM 2.5 exposure on liver metabolism in mice with asthma symptoms remains unclear. We established an ovalbumin (OVA)-induced asthma model in mice and divided the animals into four groups: control group (C), PM 2.5 exposure group (P), OVA-induced asthma group (O) and OVA-induced asthma PM 2.5 exposure group (OP). Gas chromatography-mass spectrometry (GC-MS) was used to identify the metabolite markers and related perturbed metabolic pathways in mouse liver tissue after PM 2.5 exposure. Multivariate analysis showed 9 and 12 potential metabolite markers in the P and OP groups, respectively, after PM 2.5 exposure that were significantly correlated with lipid peroxidation indices. PM 2.5 exposure perturbed 5 and 7 metabolic pathways in the P and OP groups, respectively. These metabolic pathways mainly involve the lipid metabolism, amino acid metabolism, carbohydrate metabolism, and nucleotide metabolism. These results highlight the potential to study PM 2.5 -triggered alterations via liver tissue in normal and OVA-induced asthmatic mice to gain a more realistic appraisal of the resulting early toxicity events. Additionally, these results revealed potential metabolite markers of early antioxidant defense events triggered by PM 2.5 and indicated that metabolite markers are more sensitive than antioxidant indicators. Image 1 • Metabolic disorders were observed in liver tissues of normal mice and OVA-induced asthma mice after PM 2.5 exposure. • After exposure to PM 2.5 , 9 and 12 metabolic markers were screened in normal mice and asthmatic mice, respectively. • Perturbed metabolic pathways mainly involved the metabolism of lipid, amino acid, carbohydrate, and nucleotide metabolism. • Metabolomics plays a significant role in exploring the toxicity mechanism of PM 2.5 in mouse liver. [ABSTRACT FROM AUTHOR]

Abstract The risk of development of asthma, a multi-faceted chronic disease, increases as a result of exposure to PM 2.5. However, the mechanism underlying asthma-related metabolic changes caused by PM 2.5 exposure is unclear. Here, we investigated the major metabolic changes, metabolic pathways involved, and underlying molecular mechanisms in mice with PM 2.5 exposure-induced asthma. Forty-eight adult female mice were randomly assigned to control (C), low concentration-PM 2.5 exposure: 0.50 mg kg−1 (L), medium concentration-PM 2.5 exposure: 1.58 mg kg−1 (M), and high concentration-PM 2.5 exposure: 4.98 mg kg−1 (H) groups. M and H groups presented significantly higher IL-4, IL-8, IL-1β, IL-5, IL-13, and OVA-specific IgE levels, and significantly lower IFN-γ levels, than the C group, as well as significantly increased eosinophil count and MUC5AC expression in the lung tissue. These findings indicate that exposure to medium and high concentrations of PM 2.5 induced asthma in mice. Statistical analyses identified 13 asthma-related major metabolites, which were analyzed by gas chromatography-mass spectrometry (GC-MS). Meta Mapp Software revealed 4 major metabolic pathways. PM 2.5 -induced ATP requirement and oxidative stress may perturb metabolic processes in asthma. The present findings increase our understanding of the toxic effect of PM 2.5 in the development of asthma and identify potentially useful biomarkers. Graphical abstract Image 1 Highlights • PM 2.5 induces asthma in mice. • GC-MS analysis identified 13 biomarkers in PM 2.5 -induced asthmatic mice. • Screening identified four metabolic pathways involved in the pathogenesis of asthma. • PM 2.5 regulates amino acid and purine metabolism by disrupting the TCA cycle. [ABSTRACT FROM AUTHOR]