Inflammatory and Cytotoxic Responses in Mouse Lungs Exposed to Purified Toxins from Building Isolated Penicillium brevicompactum Dierckx and P. chrysogenum Thom.

Abstract

In vitro and in vivo studies have shown that building-associated Penicillium spores and spore extracts can induce significant inflammatory responses in lung cells and animal models of lung disease. However, because spores and spore extracts comprise mixtures of bioactive constituents often including toxins, it is impossible to resolve which constituent mediates inflammatory responses. This study examined dose-response (0.5 nM, 2.5 nM, 5.0 nM, 12.5 nM/g body weight (BW) animal) and time-course (3, 6, 24 and 48 h post instillation (PI)) relationships associated with inflammatory and cytotoxic responses in mouse lungs intratracheally instilled with pure brevianamide A, mycophenolic acid, and roquefortine C. High doses (5.0 nM and/or 12.5 nM/g BW animal) of brevianamide A and mycophenolic acid, the dominant metabolites of P. brevicompactum, and roquefortine C, the dominant metabolite of P. chrysogenum, induced significant inflammatory responses within 6 h PI, expressed as differentially elevated macrophage, neutrophil, MIP-2, TNF, and IL-6 concentrations in the bronchioalveolar lavage fluid (BALF) of intratracheally exposed mice. Macrophage and neutrophil numbers were maximal at 24 h PI; responses of the other inflammatory markers were maximal at 6 h PI. Except for macrophage numbers in mycophenolic acid-treatment animals, cells exhibited significant dose-dependent-like responses; for the chemo-/cytokine markers, dose dependency was lacking except for MIP-2 concentration in brevianamide A-treatment animals. It was also found that brevianamide A induced cytotoxicity expressed as significantly increased LDH concentration in mouse BALF, at concentrations of 12.5 nM/g BW animal and at 6 and 24 h PI. Albumin concentrations, measured as a nonspecific marker of vascular leakage, were significantly elevated in the BALF of mice treated with 12.5 nM/g nM brevianamide A/animal from 6 to 24 h PI and in > or =5.0 nM/g mycophenolic acid-treated animals at 6 to 24 h PI. These results suggest that these three toxins from Penicillium species common on damp materials in residential housing provoke compound-specific toxic responses with different toxicokinetics. Moreover, that these toxins can stimulate significant inflammatory responses in vivo might help explain some of the indoor effects associated with Penicillium spore exposures in indoor environments.

Comparison of Inflammatory Responses in Mouse Lungs Exposed to Atranones A And C fromStachybotrys Chartarum

“…However, that there were differential dose-and time-dependent inflammatory cell and proinflammatory mediator responses in BALF of mice instilled with the two atranone types suggests that there are differences in toxicological and pharmacokinetic properties among atranones. Interestingly, this supports results of Nielsen et al (2002), who reported that atranone B-containing spore extracts were apparently more inflammatory toward RAW264.7 macrophages than those with atranone D. This also provides further support for previous studies suggesting that exposure to fungal spores, their extracts, and toxins results in differing lung inflammatory response patterns (Flemming et al, 2004;Hudson et al, 2005;Leino et al, 2003;Rand et al, 2005;Shahan et al, 1998).…”

“…That these types of response patterns were observed is not unusual. Such responses have been documented in a variety of in vitro and in vivo studies of exposures to nonbiological particulates, bacteria and bacterial endotoxin, and fungal spores, allergens, and toxins (Fogelmark et al, 1992;Chung et al, 2005;Driscoll et al, 1995;Flemming et al, 2004;Bondy and Pestka, 2000;Brown and Gordon, 2001;Jakab et al, 1994;Jussila et al, 2002;Mason et al, 1998;Mi-Gyung et al, 1999;Rand et al, 2005;Vassallo et al, 2000). However, that there were differential dose-and time-dependent inflammatory cell and proinflammatory mediator responses in BALF of mice instilled with the two atranone types suggests that there are differences in toxicological and pharmacokinetic properties among atranones.…”

A review of the methodology for assessing in vivo antioxidant capacity

“…Enzymatic methods are also available for most proteins, including albumin, which makes analysis more accessible. 26 Supplementation trials have been undertaken aimed at boosting various endogenous antioxidant levels. For example, the thiol-containing compound N-acetylcysteine (NAC), has been used in a variety of cell, animal and human studies, due to its ability to replete reduced glutathione levels, by providing cysteine intracellularly.…”

Associations between Fungal Species and Water-Damaged Building Materials

“…growing on damp building materials do not readily become airborne and/or lose their culturability soon after liberation (21,29,45,47) and may therefore not be detected during air or dust sampling. Correct species identification of the fungi is also important, since new research has indicated that species-specific metabolites, like atranone C produced by Stachybotrys chlorohalonata (37), are cytotoxic or immunotoxic or induce inflammatory responses when inhaled (24,33,34). The purpose of this study was therefore to estimate the qualitative and quantitative diversity of fungi growing on damp or water-damaged building materials.…”