Time course of pulmonary burden in mice exposed to residual oil fly ash

Abstract

Residual oil fly ash (ROFA) is a common pollutant in areas where oil is burned. This particulate matter (PM) with a broad distribution of particle diameters can be inhaled by human beings and putatively damage their respiratory system. Although some studies deal with cultured cells, animals, and even epidemiological issues, so far a comprehensive analysis of respiratory outcomes as a function of the time elapsed after exposure to a low dose of ROFA is wanted. Thus, we aimed to investigate the time course of mechanical, histological, and inflammatory lung changes, as well as neutrophils in the blood, in mice exposed to ROFA until 5 days after exposure. BALB/c mice (25 ± 5 g) were randomly divided into 7 groups and intranasally instilled with either 10 μL of sterile saline solution (0.9% NaCl, CTRL) or ROFA (0.2 μg in 10 μL of saline solution). Pulmonary mechanics, histology (normal and collapsed alveoli, mononuclear and polymorphonuclear cells, and ultrastructure), neutrophils (in blood and bronchoalveolar lavage fluid) were determined at 6 h in CTRL and at 6, 24, 48, 72, 96, and 120 h after ROFA exposure. ROFA contained metal elements, especially iron, polycyclic aromatic hydrocarbons (PAHs), and organochlorines. Lung resistive pressure augmented early (6 h) in the course of lung injury and other mechanical, histological and inflammatory parameters increased at 24 h, returning to control values at 120 h. Blood neutrophilia was present only at 24 and 48 h after exposure. Swelling of endothelial cells with adherent neutrophils was detected after ROFA instillation. No neutrophils were present in the lavage fluid. In conclusion, the exposure to ROFA, even in low doses, induced early changes in pulmonary mechanics, lung histology and accumulation of neutrophils in blood of mice that lasted for 4 days and disappeared spontaneously.

Exposure to Fine Particles by Mine Tailing and Lung Function Effects in a Panel of Schoolchildren, Chañaral, Chile

“…The average metal and metalloid concentrations found in the PM 10 in Chañaral were generally greater than those reported by other studies in different cities and mining zones in northern Chile and are consistent with the metal measured for this population in different studies [17] [18] [26] [28]. Several studies in animal models suggest that the bioavailable metal transition is one the primary determinants of the acute inflammatory response for both the combustion source and ambient PM samples [2] [29]- [31]. Genotoxic and epigenotoxic effects on human bronchial epithelial cells have been reported due to variable concentrations of transition metals and organic compounds [32] [33].…”

Assessing regulatory features of the current transcriptional network of Saccharomyces cerevisiae

“…Finally, in the case of the Multidrug resistance (MDR) functional category, only three genes (6.67%) belong to the 10–25 in-degree bin: TPO4 with 12 regulators, and AQR1 and PDR5 with both 11 regulators. These genes are involved in multiple functions 31 , 32 . In particular, PDR5 , controls resistance to a wide range of unrelated drugs, steroid transport, response to cation stress and cellular detoxification even when growing exponentially in liquid culture 31 .…”

Aerobic training reduces oxidative stress in skeletal muscle of rats exposed to air pollution and supplemented with chromium picolinate

“…Interestingly, acute inhalation of concentrated ambient particles and ROFA has been found to lead to potential oxidant injuries, followed by an up-regulation of antioxidant defenses. After a 24 h inhalation period, reversibility of oxidative stress occurs, suggesting that oxidants mediated by pollution exposure may trigger adaptive responses in the lungs and heart [40][41][42][43]. Moreover, our study was performed using healthy animals.…”