Re: Rand & Miller~Inflammation From Fungi~Toxins

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I heard Mighty Mouse is looking for you.....drop enough cheese
and you might get some stalwart sidekicks until the chips are down.

On 12/28/09, Mike B. wrote:
> Do you have mouse lungs? If not, this is not applicable to
> humans.
>
> On 12/23/09, Sharon wrote:
>> Arch Toxicol. 2009 Nov 11. [Epub ahead of print]
>>
>>
>>
>> Dectin-1 and inflammation-associated gene transcription and
>> expression in mouse lungs by a toxic (1,3)-beta-D: glucan.
>>
>> Rand TG, Sun M, Gilyan A, Downey J, Miller JD.
>>
>>
>>
>> Department of Biology, Saint Mary's University, 923 Robie
>> St., Halifax, NS, B3H 3C3, Canada, thomas.rand@smu.ca.
>>
>>
>>
>> The form of (1-3)-beta-D: glucan found in the cell walls of
>> the anamorphic Trichocomaceae that grow on damp building
>> materials is considered to have potent toxic and
>> inflammatory effects on cells of the respiratory system. It
>> is also considered to have a potential role in the
>> development of non-allergenic respiratory health effects.
>> While human studies involving experimental exposures all
>> point to the inflammatory potential of pure curdlan, a
>> linear (1-3)-beta-D: glucan in a triple helix
>> configuration, animal experiments result in conflicting
>> conclusions concerning the inflammatory potency of this
>> glucan. However, because mice appear to be a better model
>> than guinea pigs for exploring the respiratory effects of
>> curdlan and because molecular mechanisms associated with
>> this glucan remain largely unknown, we conducted further
>> work to clarify the role of curdlan on the inflammatory
>> response using our mouse model of lung disease. This study
>> used in situ hybridization (ISH) to probe dectin-1 mRNA
>> transcription with a digoxigenin-labeled cDNA probe, with
>> reverse transcription (RT)-PCR based arrays used to measure
>> inflammation gene and receptor transcriptional responses.
>> Also, immunohistochemistry (IHC) was used to probe dectin-1
>> as well as anti-mouse Ccl3, Il1-alpha, and TNF-alpha
>> expression to evaluate dose and time-course (4 and 12 h)
>> postexposure (PE) response patterns in the lungs of
>> intratracheally instilled mice exposed to a single 50 mul
>> dose of curdlan at 10(-7), 10(-8), 10(-9), and 10(-10)
>> M/animal (=4 mug to 4 ng curdlan/kg lung wt). Dectin-1 mRNA
>> transcription and expression was observed in bronchiolar
>> epithelium, alveolar macrophages (AMs), and alveolar type
>> II cells (ATIIs) of lungs exposed to 4 mug to 40 ng
>> curdlan/kg lung wt, at both time points. Compared to
>> controls, array analysis revealed that 54 of 83 genes
>> assayed were significantly modulated by curdlan. mRNA
>> transcription patterns showed both dose and time
>> dependency, with highest transcription levels in 10(-7) and
>> 10(-8) M treatment animals, especially at 4-h PE. Nine gene
>> mRNA transcripts (Ccl3, Ccl11, Ccl17, Ifng, Il1alpha, Il-
>> 20, TNF-alpha, Tnfrsf1b, and CD40lg) were significantly
>> expressed at all doses suggesting they may have a central
>> role in immunomodulating curdlan exposures. IHC revealed
>> Ccl3, Il1-alpha, and TNF-alpha expression in bronchiolar
>> epithelium, AMs and ATIIs illustrate the important
>> immunomodulatory role that these cells have in the
>> recognition of, and response to glucan. Collectively, these
>> results confirm the inflammatory nature of curdlan and
>> demonstrate the complex of inflammation-associated gene
>> responses induced by (1-3)-beta-D: glucan in triple helical
>> forms. These observations also provide a biological basis
>> for the irritant and inflammatory response to curdlan
>> observed in humans and animals in experimental studies.
>>
>>
>>
>>
>>
>> Chem Biol Interact. 2010 Jan 5;183(1):113-24.
>>
>>
>>
>> Inflammation-associated gene transcription and expression
>> in mouse lungs induced by low molecular weight compounds
>> from fungi from the built environment.
>>
>> Miller JD, Sun M, Gilyan A, Roy J, Rand TG.
>>
>>
>>
>> Department of Chemistry, Carleton University, Ottawa,
>> Ontario, Canada K1S 5B6.
>>
>>
>>
>> Few metabolites from fungi found indoors have been tested
>> for inflammatory mediators endpoints in primary cultures of
>> alveolar macrophages or in vivo. In this study, mice were
>> intratracheally instilled with a single dose comprising 4x10
>> (-5)moletoxin/kg lung wt dose of either atranone C,
>> brevianamide, cladosporin, mycophenolic acid, neoechinulin
>> A & B, sterigmatocystin or TMC-120A. These toxins are from
>> fungi common on damp building materials. The dose used was
>> comparable to the estimated doses of possible human
>> exposure. Hematoxylin and eosin (H&E) histology and Alcian
>> Blue/Periodic Acid Schiff (AB/PAS) histochemistry were used
>> to evaluate lungs for time course (4h and 12h post-exposure
>> (PE)) inflammatory and toxic changes. Reverse-transcription
>> (RT)-PCR based arrays were also employed to evaluate time
>> course inflammation-associated gene transcription in lung
>> tissues of the different toxins. Immunohistochemistry (IHC)
>> was used to probe MIP-2 and Tnf-alpha protein expression in
>> treatment lungs to determine whether responses correspond
>> with gene transcription data. Both histology and
>> histochemistry revealed that toxin exposed lungs at 12h PE
>> showed evidence of inflammation. H&E revealed that
>> bronchioli were lined with irregularly thickened and
>> sometimes sloughing epithelium and bronchiolar spaces
>> supported infiltration of leukocytes, cellular and mucus-
>> like debris while alveolar spaces supported swollen
>> macrophages and modest amorphous debris accumulations. All
>> toxin-instilled lungs exhibited copious mucus production
>> and alveolar macrophages with red stained cytoplasm on
>> bronchiolar surfaces, especially at 12h PE. Array analysis
>> of 83 inflammation-associated genes extracted from lung
>> tissue demonstrated a number of patterns, compared to
>> controls. 82 genes assayed at 4h PE and 75 genes at 12h PE
>> were significantly altered (p< or =0.05; >or =1.5-fold or <
>> or =-1.5-fold change) in the different treatment animal
>> groups. Expression of transcriptionally regulated genes was
>> confirmed using immunohistochemistry that demonstrated MIP-
>> 2 and Tnf-alpha staining in respiratory bronchiolar
>> epithelia, alveolar macrophages and alveolar type II cells.
>> The transcriptional regulation in these genes in the
>> treatment groups suggests that they may serve central roles
>> in the immunomodulation of toxin-induced pro-inflammatory
>> lung responses. Hierarchical cluster analysis revealed
>> significant patterns of gene transcription linking the
>> response of the toxins at equimolar doses in three groups:
>> (1) brevianamide, mycophenolic acid and neoechinulin B, (2)
>> neoechinulin A and sterigmatocystin, and (3) cladosporin,
>> atranone C and TMC-120. The results further confirm the
>> inflammatory nature of metabolites/toxins from such fungi
>> can contribute to the development of non-allergenic
>> respiratory health effects