Effects of particulate matter on allergic respiratory diseases

Abstract

The health impact of airborne particulate matter (PM) has long been a concern to clinicians, biologists, and the general public. With many epidemiological studies confirming the association of PM with allergic respiratory diseases, an increasing number of follow-up empirical studies are being conducted to investigate the mechanisms underlying the toxic effects of PM on asthma and allergic rhinitis. In this review, we have briefly introduced the characteristics of PM and discussed its effects on public health. Subsequently, we have focused on recent studies to elucidate the association between PM and the allergic symptoms of human respiratory diseases. Specifically, we have discussed the mechanism of action of PM in allergic respiratory diseases according to different subtypes: coarse PM (PM_2.5-10), fine PM (PM_2.5), and ultrafine PM.

Keywords: Allergic respiratory diseases; Coarse PM; Fine PM; Particulate matter; Ultrafine PM.

Fig. 1

Different pathways of PM toxicity and their mechanisms in allergic respiratory diseases. (A) PM_2.5-10 activates neutrophils and eosinophils; (B) PM_2.5 induces antigen-presenting cell-mediated inflammatory responses; (C) PM_2.5 induces oxidative stress; (D) PM_2.5 leads to apoptosis and autophagy; and (E) PM_2.5 causes imbalance of T helper cells. PM: particulate matter; NE: neutrophils; EOS: eosinophils; IL: interleukin; H1R: H1 receptor; GM-CSF: granulocyte-macrophage colony stimulating factor; TNF: tumor necrosis factor; COX-2: cyclooxygenase-2; PI3K: phosphatidylinositol-4,5-bisphosphate 3-kinase; PIP2: phosphatidylinositol (4,5)-bisphosphate; PIP3: phosphatidylinositol (3,4,5)-trisphosphate; PTEN: phosphatase and tensin homolog; NrF2: nuclear factor (erythroid-derived 2)-like 2; PDK1: phosphoinositide-dependent kinase-1; Akt: protein kinase B; PKB: protein kinase B; GCLC: glutamate-cysteine ligase catalytic subunit; HO-1: heme oxygenase-1; NQO-1: NADPH quinone oxidoreductase; GSK-3β: glycogen synthase kinase-3 beta; Caspase: cysteine aspartic acid protease; Rac1: ras-related C3 botulinum toxin substrate 1; p70s6k: p70 ribosomal protein S6 kinase; mdm2: Mouse double minute 2 homolog; APC: antigen-presenting cell; CD: cluster of differentiation; CR3: complement receptor 3; LC3A/B: light chain 3A/B; IFN-γ: interferon-gamma; ST2: IL-33 receptor; Th: T-helper; UFP: ultrafine particulate matter.