OCR Text |
Show Exposure to wood smoke particulate matter (WSPM) has been linked to exacerbation of asthma, development of chronic obstructive pulmonary disease (COPD), and premature death. Combustion-derived P M (cdPM) such as cigarette smoke (CS), diesel exhaust (DEP), and WSPM, activate transient receptor potential ankyrin-1 (TRPA1) which promotes neurogenic inflammation/edema and airway irritation/cough.The mechanism ofTRPAl activation by DEP and CS involves the electrophilic/oxidant binding (3CK) and menthol-binding (ST) sites, and a novel mechanosensitive site. W e hypothesized that W S P M would activate TRPA1 through one or more of these sites similar to other cdPM. Pine and mesquite P M were generated in the laboratory. Both types of W S P M particles activated TRPA1 in human TRPA1 over-expressing HEK-293 and primary mouse trigeminal (TG) neurons. W S P M also activated TRPA1 in A549 cells, a human alveolar adenocarcinoma cell line, which has recently been shown to express TRPA1. HC-030031, a TRPA1 specific antagonist, attenuated the calcium flux due to W S P M treatment in both human A459 cells and mouse primary TG neurons. Differential activation of TRPA1, as a function of particle size, demonstrated that PM<2.5 urn were most potent. Several known chemical components of WSPM, including 3,5-ditert-butylphenol and agathic acid were TRPA1 agonists. Both W S P M and agathic acid activated TRPA1 primarily via binding the 3CK site, based on inhibition of calcium flux by glutathione and mutation of the 3CK site. Conversely, 3,5-ditert-butylphenol activated TRPA1 through the ST site. This study established the mechanism by which W S P M and associated chemical components activated TRPA1 which may help tailor effective therapeutic treatments for W S P M pneumotoxicity. Support: NIEHS ES017431 and the University of Utah Undergraduate Research Opportunities Program. 22 I robustly activated TRPA1. Conclusions: •Mesquite and pine WJ •In mouse TG neurons an in AS49s. a human adertocafciooma cell line. W S P M induced Ca-"' flux i inhibited by the TRPA1 antagonist HC-030031 >PM<5 p m was the most potent form of W S P M . •Pine, mesquite, and the pine needle toxin agathic add TRPA1 through the etoctrophilc binding site. • W S P M component 3,5-ditertbutyt phenol activates TRPA1 though e menthot/propofol binding site. •Establishment of the mechanism by which W S P M activate TRPA1 may help tailor effective therapeutic treatments for pneurnotoxJcity |