Cardiopulmonary Toxicity Study of Ambient Particulate Matters in Diseased Animal Models 1. Effects of Particle Size and Season 2. Effects of DEPs and LPS
Date Issued
2006
Date
2006
Author(s)
Ho, Wei-Ju
DOI
zh-TW
Abstract
Part I Effects of Particle Size and Season
Increased cardiovascular and respiratory mortality have been associated with elevated concentration of ambient particulate matters (PM). However, the underlying mechanism remains unclear. Our study at supersite also revealed that PM might induce cardiovascular toxicity. Thus, we further examined the cardiovascular toxicity of PM of different sizes and seasons in spontaneously hypertensive rat (SHR) and STZ-diabetic rat.
The particles were collected on TEOM (Tapered-Element Oscillating Microbalance) at Hsing-Chuang supersite where the data of its composition and size distribution were determined. The SHR and STZ-diabetic rats were intratracheally administered with PM2.5 and PM10-2.5 of different seasons. They were sacrificed 24hrs after exposure and levels of CRP for systemic inflammation, NO for endothelial function and fibrinogen for blood clotting function were determined in peripheral blood. We also collected bronchoalveolar lavage fluid to analyze lung injury. Wilcoxon Rank Sum test was used to compare between the experimental and control groups on lung inflammation and cardiovascular biomarkers.In animals treated with PM collected from supersite, we found that fibrinogen increased in diabetic rats and SHR after PM exposure. NO also decreased in SHR after PM exposure. It appears diseased animals were more susceptible to PM administration. We also found that PM of different seasons might induce different effects, but there was no difference between PM2.5 and PM10-2.5.
Ambient PM can cause lung and cardiovascular toxicity, and the the effects are more prominent in diseased animals. The different effects in different seasons may be explained by the components of PM.
Part II Effects of DEPs and LPS
Diesel exhausts particles (DEPs) are one of the primary compositions in suspended particulate matter in a metropolitan area. Studies showed that DEPs’ exposure can cause inflammation in lungs. Further research discovered that, in DEPs’ ultrafine particle can result in thrombus formation or blood clots. The bacterium endotoxin (LPS) is one of the main compositions in suspended particulate matter. Exposure to LPS can cause pneumonia and affect functions of the lungs cells, and it may also affect TLR to induce more cytokine release and affect endothelial function. Because these two components are important in ambient particles, therefore we want to clarify these two componetes effects on cardiovascular parameters by using diabetic rats, and try to investigate the interaction between these two components.
We respectively divided the diabetic rats and the healthy SD rats into four groups, and each rat was injected by means of intratracheal instillation with saline, DEPs 2 mg/kg, LPS 2 mg/kg, as well as DEPs +LPS. Rats are then sacrificed twenty four hours after the injection, lungs and the peripheral blood samples are then collected to for the analysis of systemic inflammation CRP, endothelial dysfunction NO、blood clotting function fibrinogen, and BALF is also collected simultaneously for the analysis of lung inflammation and injury index. Finally, Wilcoxon Rank Sum test was used to compare the results between experimental group and the controlled group for lung inflammation index and cardiovascular index, statistical analysis is then done on the different compositions. The result showed that DEPs, LPS, and DEPs +LPS can cause lungs inflammation response, increase in peripheral blood fibrinogen and NO drop in the diabetic rats and the healthy SD rats, simultaneous exposure to both DEPs and LPS creates a much stronger effect when compared to individual exposure to DEPs or LPS, additivity response between diabetes and particulate matter on NO can be observed on the diabetic rats.
DEPs and LPS can result in lung inflammation and a change in cardiovascular index, susceptibility animals like diabetic rats tends to have a stronger cardiovascular effect, and the speculation is that it is the result of the correlations between the different particles.
Subjects
微粒空氣污染
心血管疾病
疾病動物模式
柴油引擎微粒
內毒素
ambient particulate matters
cardiovascular disease
diseased animal models
Diesel exhaust particle
Lipopolysaccharide
SDGs
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-95-R93841008-1.pdf
Size
23.31 KB
Format
Adobe PDF
Checksum
(MD5):0a0e4b782ca051684fbee1fb6ac24a3f