Effects of chronic exposure to air pollution from Sao Paulo city on coronary of Swiss mice, from birth to adulthood.
To explore the hypothesis that air pollution promotes cardiovascular changes, Swiss mice were continuously exposed, since birth, in two open-top chambers (filtered and nonfiltered for airborne particles <or= 0.3 microm) placed 20 m from a street with heavy traffic in downtown Sao Paulo, twenty-four hours per day for four months. Fine particle (PM(2.5)) concentration was determined gravimetrically; hearts were analyzed by morphometry. There was a reduction of the PM(2.5) inside the filtered chamber (filtered = 8.61+/-0.79 microg/m(3), nonfiltered = 18.05+/-1.25 microg/m(3), p < .001). Coronary arteries showed no evidence of luminal narrowing in the exposed group but presented higher collagen content in the adventitia of LV large-sized and RV midsized vessels (p = .001) and elastic fibers in both tunicae adventitia and intima-media of almost all sized arterioles from both ventricles (p = .03 and p = .001, respectively). We concluded that chronic exposure to urban air since birth induces mild but significant vascular structural alterations in normal individuals, presented as coronary arteriolar fibrosis and elastosis. These results might contribute to altered vascular response and ischemic events in the adulthood.
Akinaga
Lícia Mioko Yoshizaki
LM
Experimental Air Pollution Laboratory, School of Medicine, University of São Paulo, Brazil.
Lichtenfels
Ana Julia
AJ
Carvalho-Oliveira
Regiani
R
Caldini
Elia Garcia
EG
Dolhnikoff
Marisa
M
Silva
Luiz Fernando Ferraz
LF
Bueno
Heloisa Maria De Siqueira
HM
Pereira
Luiz Alberto Amador
LA
Saldiva
Paulo Hilário Nascimento
PH
Garcia
Maria Lúcia Bueno
ML
D000375:Aging / Q000502:physiology*; D000393:Air Pollutants / Q000009:adverse effects*; D000397:Air Pollution / Q000009:adverse effects*; D000818:Animals; D001938:Brazil; D002947:Cities; D003094:Collagen / Q000032:analysis; D003331:Coronary Vessels / Q000473:pathology*; D004547:Elastic Tissue / Q000473:pathology; D005355:Fibrosis / Q000473:pathology; D019570:Inhalation Exposure / Q000009:adverse effects*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D010316:Particle Size; D052638:Particulate Matter / Q000009:adverse effects*; D013997:Time Factors; D036401:Toxicity Tests, Chronic; D017539:Tunica Intima / Q000473:pathology; D017540:Tunica Media / Q000473:pathology
D000393:Air Pollutants; D052638:Particulate Matter; D003094:Collagen