Alveolar macrophages suppress non-specific inflammation caused by inhalation challenge with trimellitic anhydride conjugated to albumin

Occupational exposure to low molecular weight chemicals, like trimellitic anhydride (TMA), can result in occupational asthma. Alveolar macrophages (AMs) are among the first cells to encounter these inhaled compounds and were previously shown to affect TMA-induced asthma-like symptoms in the Brown Norway rat (Valstar et al., Toxicol. Appl....

Alveolar macrophages have a dual role in a rat model for trimellitic anhydride-induced occupational asthma

Occupational exposure to low molecular weight chemicals, like trimellitic anhydride (TMA), can result in occupational asthma. Alveolar macrophages (AMs) are among the first cells to encounter inhaled compounds. These cells can produce many different mediators that have a putative role in asthma. In this study, we examined the role of AMs in lung...

Use of physicochemical calculation of pKa and CLogP to predict phospholipidosis-inducing potential: A case study with structurally related piperazines

Several cationic amphiphilic compounds are known to induce phospholipidosis, a condition primarily characterized by excessive accumulation of phospholipids in different cell types, giving the affected cells a finely foamy appearance. Excessive storage of lamellar membranous intralysosomal inclusion bodies is the hallmark for phospholipidosis on...

Increased activity of matrix metalloproteinase-8 and matrix metalloproteinase-9 in induced sputum from patients with COPD

Background: The increased expression of matrix metalloproteinases (MMPs) is considered to be a key factor in the development of COPD. Net MMP activity represents a tightly regulated process, which is not addressed by conventional investigation methods such as messenger RNA or protein expression. Yet, quantitative data on MMP activity in the...

Suppression of the acute inflammatory response of porcine alveolar- and liver macrophages

During infection and inflammation drug disposition and hepatic metabolism are markedly affected in mammals. Pro-inflammatory mediators play an important role in the suppression of (cytochrome-P450-mediated) drug metabolism. Inflammatory mediators like cytokines, nitric oxide (NO), reactive oxygen species (ROS) and eicosanoids are released by...

Comparative sensitivity of histo-pathology and specific lung parameters in the detection of lung injury

The sensitivity of different parameters for the determination of lung injury caused by nitrogen dioxide (NO2) was investigated. Male rats were exposed to concentrations of 0, 4, 10 or 25 ppm NO2 for 6 h/day, for 7, 14 or 21 days. Histopathology of the nasal cavity, larynx, trachea and lungs was compared with the changes in macrophage function...

Effect of variable versus fixed exposure levels on the toxicity of acetaldehyde in rats

The effects of exposure pattern on the toxicity of acetaldehyde vapour were investigated in 4-week inhalation studies. Male rats were exposed to 500 or 150 and 110 ppm for 6 h per day/5 days per week. One group of animals was exposed without interruption, the exposure of a second group was interrupted for 1.5 h between the first and second 3-h...