Ozone augments interleukin-8 production induced by ambient particulate matter

Abstract

BackgroundExperimental and controlled human exposure studies have demonstrated additive effects of ambient particulate matter and ozone on health. A few epidemiological studies have suggested that ambient particulate matter components are important for the combined effects of ambient particulate matter and ozone on health. However, few studies have examined whether ozone changes the effects of ambient particulate matter on pro-inflammatory cytokine production. In this study, the influence of ozone on pro-inflammatory cytokine production in response to ambient particulate matter was evaluated.ResultsAmbient particulate matter smaller than 1 μm was collected and the suspension of this particulate matter was bubbled through 0.12 ppm and 0.24 ppm ozone. THP1 cells were stimulated by the solution containing the particulate matter with and without bubbling through ozone at 1 μg/mL. The interleukin-8 concentrations in the supernatants of THP1 cells stimulated by collected particulate matter dissolved in solution were 108.3 ± 24.7 pg/mL without ozone exposure, 165.0 ± 26.1 pg/mL for 0.12 ppm ozone bubbling for 1 min, 175.1 ± 33.1 pg/mL for 0.12 ppm for 5 min, 183.3 ± 17.8 pg/mL for 0.12 ppm for 15 min, 167.8 ± 35.9 pg/mL for 0.24 ppm for 1 min, 209.2 ± 8.4 pg/mL for 0.24 ppm for 5 min, and 209.3 ± 14.3 pg/mL for 0.24 ppm for 15 min. Ozone significantly increased interleukin-8 concentrations compared to those for particulate matter dissolved in solution without ozone exposure and the solvent only (8.2 ± 0.9 pg/mL) in an ozone concentration-dependent manner. Collected particulate matter in solutions with or without bubbling through ozone had no effect on interleukin-6 production. The antioxidant N-acetyl-L-cysteine significantly inhibited the increases in interleukin-8 induced by solutions with particulate matter, regardless of ozone exposure. The reactive oxygen species concentration in solutions with collected particulate matter was not associated with ozone bubbling.ConclusionOzone may augment the production of interleukin-8 in response to ambient particulate matter by a mechanism unrelated to reactive oxygen species. These results support the epidemiological evidence for combined effects of ambient particulate matter and ozone on human health.

Can atmospheric pollution be considered a co-factor in extremely high level of SARS-CoV-2 lethality in Northern Italy?

“…Also, a high correlation between nitrogen dioxide (NO 2 ) and particulate in inducing IL-6 hyperexpression was found (Perret et al, 2017), being both responsible of an inflammatory status even in a pediatric population (Gruzieva et al, 2017). Among the other more common pollutants, ozone (O 3 ) and sulfur dioxide (SO 2 ) have also a prominent role in inducing systemic and respiratory system inflammation, particularly via IL-8 (Kurai et al, 2018), IL-17 (Che et al, 2016) and TNF-a (Cho et al, 2007), both in vitro and in vivo (Knorst et al, 1996). All these modifications are well known to contribute to atherogenesis, chronic respiratory diseases and cardiovascular events, the latter strictly correlated with IL-6 serum levels (Aromolaran et al, 2018).…”

COVID-19 in the environment

“…There is scientific evidence that exposes a high correlation between the presence of ozone (O 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ) and fine particles in the induction of hyperexpression of proinflammatory interleukins ( Kurai et al., 2018 ; Perret et al., 2017 ). NO 2 is a common marker of air pollution/industrial activity, associated with morbidity and mortality ( He et al., 2020 ).…”

Comparison of Cervical Levels of Interleukins-6 and -8 in Patients with and without Cervical Intraepithelial Neoplasia

“…IL-8 is normally secreted by normal cells in very small amounts, whose production and secretion increases following the increased levels of other pro-inflammatory cytokines such as IL-1 and tumor necrosis factor (TNF), bacterial and viral products, and cellular stress (Kurai et al, 2018). Previous studies conducted on the association among serum, intracellular, and extracellular levels of this factor showed that the IL-8 level significantly increases in the presence of malignancies such as melanoma, breast carcinoma, ovarian malignancies, and pancreatic cancer (Green et al, 1996;Chen et al, 2014;Chia et al, 2014;Yung et al, 2018).…”