Peroxyacetyl nitrate-induced oxidative and calcium signaling events leading to cell death in ozone-sensitive tobacco cell-line

Abstract

It has long been concerned that some secondary air pollutants such as smog components, ozone (O 3 ) and peroxyacetyl nitrate (PAN), are highly phytotoxic even at low concentrations. Compared with the biology of O 3 , we largely lack the information on the toxicity model for PAN at the cellular signaling levels. Here, we studied the cell-damaging impact of PAN using suspension culture of smog-sensitive tobacco variety (Bel-W3). The cells were exposed to freshly synthesized PAN and the induced cell death was assessed under microscope after staining with Evans blue. Involvement of reactive oxygen species (ROS) in PAN toxicity was suggested by PAN-dependently increased intracellular H 2 O 2 and also by the cell-protective effects of ROS scavengers and related inhibitors. Calcium chelator also lowered the level of PAN-induced cell death, indicating that Ca 2+ is also involved. Using a transgenic cell line expressing aequorin, an increase in cytosolic Ca 2+ concentration responsive to the pulse of PAN, but sensitive to Ca 2+ channel blockers, was recorded, indicating that Ca 2+ channels are activated by PAN or PAN-derived signals. Above data show some similarity between the signaling mechanisms responsive to O 3 and PAN.

Secondary Organic Aerosol Generated from Biomass Burning Emitted Phenolic Compounds: Oxidative Potential, Reactive Oxygen Species, and Cytotoxicity

“…In the atmospheric oxidation processes of phenolic compounds, organic hydroperoxides are formed in the “RO 2 +HO 2 ” pathway (Yee et al, 2013; Wang et al., 2017), , while PANs are produced through the “RO 2 +NO” pathway. Both organic hydroperoxides and PANs can hydrolyze to form H 2 O 2 in the liquid phase. − As shown in Table , the presence of NO x promoted the formation of PANs and inhibited organic peroxides, which is in line with theoretical expectations. The low NO x condition has no significant ( p > 0.05) impact on the H 2 O 2 yield of the “0.5 days” Phc-SOA, which likely indicates the balancing of an increase in PANs and a decrease in organic hydroperoxides.…”

Aerosol Promotes Peroxyacetyl Nitrate Formation During Winter in the North China Plain

“…Peroxyacetyl nitrate (PAN, CH 3 C­(O)­OONO 2 ) is an important secondary gaseous pollutant commonly found in photochemical smog and is hazardous to human health and the ecosystem (1–2 magnitudes more phytotoxic than O 3 ). − Additionally, PAN enables the long-range transport of nitrogen oxides (NO x ) once reaching the free troposphere, , which is why its formation in polluted regions is highly important and not only of local concern. − …”

A Novel Wild-Land Fire-Fighting Foam for Minimizing the Phytotoxicity of Wood Burning-Derived Smoke Tested in Living Plant Cells

“…Plant cell death analysis. We have previously evaluated the phytotoxicity of gaseous components in the atmosphere [12][13][14] and the cigarette smoke [11], by monitoring the development of cell death in the suspension cultured plant cells employed as a model. Toxicity assays using the cigarette smoke-treated tobacco cells could be a model for plant cell response to the post-combustion gases derived from plant residues.…”