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Lauren A Bright,1 Wellesley Dittmar,1 Bindu Nanduri,2 Fiona M McCarthy,3 Nisma Mujahid,2 Lais RR Costa,2 Shane C Burgess,3 Cyprianna E Swiderski11Department of Clinical Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, MS 39762, USA; 2Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, MS 39762, USA; 3School of Animal Comparative and Biomedical Sciences, College of Agriculture and Life Sciences, University of Arizona, Tucson, AZ 85721, USABackground: Pasture-associated severe equine asthma is a warm season, environmentally-induced respiratory disease characterized by reversible airway obstruction, persistent and non-specific airway hyper-responsiveness, and chronic neutrophilic airway inflammation. During seasonal exacerbation, signs vary from mild to life-threatening episodes of wheezing, coughing, and chronic debilitating labored breathing.Purpose: In human asthma, neutrophilic airway inflammation is associated with more severe and steroid-refractory asthma phenotypes, highlighting a need to decipher the mechanistic basis of this disease characteristic. We hypothesize that the collective biological activities of proteins in bronchoalveolar lavage fluid (BALF) of horses with pasture-associated severe asthma predict changes in neutrophil functions that contribute to airway neutrophilic inflammation.Methods: Using shotgun proteomics, we identified 1,003 unique proteins in cell-free BALF from six horses experiencing asthma exacerbation and six control herdmates. Contributions of each protein to ten neutrophil functions were modeled using manual biocuration to determine each protein’s net effect on the respective neutrophil functions.Results: A total of 417 proteins were unique to asthmatic horses, 472 proteins were unique to control horses (p

Valepotriates are epoxide-bearing triesters of the monoterpene alcohol 4,7-dimethylcyclopenta-( c)-pyrane isolated from the roots of several Valerianacae species. They are regarded as the main tranquilizing constituents of these drugs. Although the valepotriates valtrate/isovaltrate (VAL) and dihydrovaltrate (DH-VAL) showed a strong alkylating activity against the nucleophilic agent 4-( p-nitrobenzyl)-pyridine (NBP), they were not clearly mutagenic for the strains TA98, TA100, TA1535, and TA1537 of Salmonella typhimurium or for the strains WP2 and WP2 uvrA of Escherichia coli in the absence of a metabolic activation system (S9-mix). However, the valepotriates were mutagenic for TA100, WP2 and WP2 uvrA at concentrations up to about 1.0 μmole/plate when S9-mix was added to the test system. With more than 1 μmole/plate the valepotriates were toxic in the presence of a metabolic activation system for all strains tested. The mutagenicity of the valepotriates was inversely related to the protein content of the S9-mix used. The mutagenicity and toxicity of the valepotriates could be inhibited when the S9-mix was preincubated with the esterase inhibitor paraoxon (1 mM) for 5 min before the test compounds and bacteria were added. Therefore, bioactivation of the valepotriates by an enzymatic hydrolysis of their ester groups is considered. This could be proven by activating the valepotriates with purified esterase. [ABSTRACT FROM AUTHOR]

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