TY - JOUR
T1 - Pathological cardiopulmonary evaluation of rats chronically exposed to traffic-related air pollution
AU - Edwards, Sabrina
AU - Zhao, Gang
AU - Tran, Joanne
AU - Patten, Kelley T.
AU - Valenzuela, Anthony
AU - Wallis, Christopher
AU - Bein, Keith J.
AU - Wexler, Anthony Stein
AU - Lein, Pamela J.
AU - Rao, Xiaoquan
N1 - Funding Information:
ICP-MS measurements were performed in the OHSU Elemental Analysis Core with partial support from the National Institutes of Health (NIH) instrumentation grant S10RR025512. This work was supported by NIH (R00 ES026241 to XR, R21 ES025570, R21 ES026515, and P30 ES023513 to P.J.L.). K.T.P. was supported by NIH-funded predoctoral training programs awarded to the University of California, Davis (UC Davis; T32 MH112507 and T32 ES007059). The contents of this work do not necessarily represent the official views of the NIH, and the NIH does not endorse the purchase of any commercial products or services mentioned in the publication.
PY - 2020/12/1
Y1 - 2020/12/1
N2 - BACKGROUND: Traffic-related air pollution (TRAP) is made up of complex mixtures of particulate matter, gases and volatile compounds. However, the effects of TRAP on the cardiopulmonary system in most animal studies have been tested using acute exposure to singular pollutants. The cardiopulmonary effects and molecular mechanisms in animals that are chronically exposed to unmodified air pollution as a whole have yet to be studied. Additionally, sex-dependent toxicity of TRAP exposure has rarely been evaluated. OBJECTIVES: This study sought to assess the cardiopulmonary effect of chronic exposure to unmodified, real-world TRAP in both female and male rats. METHODS: Four-week-old male and female rats were exposed to TRAP or filtered air for 14 months in a novel facility drawing air from a major free-way tunnel system in Northern California. Inflammation and oxidative stress markers were examined in the lung, heart, spleen, and plasma, and TRAP deposits were quantified in the lungs of both male and female rats. RESULTS: Elemental analysis showed higher levels of eight elements in the female lungs and one element in the male lungs. Expression of genes related to fibrosis, aging, oxidative stress, and inflammation were higher in the rat hearts exposed to TRAP, with female rats being more susceptible than males. Enhanced collagen accumulation was found only in the TRAP-exposed female hearts. Plasma cytokine secretion was higher in both female and male rats, but inflammatory macrophages were higher only in TRAP-exposed male spleens. DISCUSSION: Our results in rats suggest pathological consequences from chronic TRAP exposure, including sex differences indicating females may be more susceptible to TRAP-induced cardiac fibrosis. https://doi.org/10.1289/EHP7045.
AB - BACKGROUND: Traffic-related air pollution (TRAP) is made up of complex mixtures of particulate matter, gases and volatile compounds. However, the effects of TRAP on the cardiopulmonary system in most animal studies have been tested using acute exposure to singular pollutants. The cardiopulmonary effects and molecular mechanisms in animals that are chronically exposed to unmodified air pollution as a whole have yet to be studied. Additionally, sex-dependent toxicity of TRAP exposure has rarely been evaluated. OBJECTIVES: This study sought to assess the cardiopulmonary effect of chronic exposure to unmodified, real-world TRAP in both female and male rats. METHODS: Four-week-old male and female rats were exposed to TRAP or filtered air for 14 months in a novel facility drawing air from a major free-way tunnel system in Northern California. Inflammation and oxidative stress markers were examined in the lung, heart, spleen, and plasma, and TRAP deposits were quantified in the lungs of both male and female rats. RESULTS: Elemental analysis showed higher levels of eight elements in the female lungs and one element in the male lungs. Expression of genes related to fibrosis, aging, oxidative stress, and inflammation were higher in the rat hearts exposed to TRAP, with female rats being more susceptible than males. Enhanced collagen accumulation was found only in the TRAP-exposed female hearts. Plasma cytokine secretion was higher in both female and male rats, but inflammatory macrophages were higher only in TRAP-exposed male spleens. DISCUSSION: Our results in rats suggest pathological consequences from chronic TRAP exposure, including sex differences indicating females may be more susceptible to TRAP-induced cardiac fibrosis. https://doi.org/10.1289/EHP7045.
UR - http://www.scopus.com/inward/record.url?scp=85097311151&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85097311151&partnerID=8YFLogxK
U2 - 10.1289/EHP7045
DO - 10.1289/EHP7045
M3 - Article
C2 - 33275451
AN - SCOPUS:85097311151
VL - 128
SP - 127003-1-127003-14
JO - Environmental Health Perspectives
JF - Environmental Health Perspectives
SN - 0091-6765
IS - 12
M1 - 127003
ER -