Nitro-Oxidative Stress in a Mice Model of Toluene Diisocyanate -Induced Asthma

Toluene-2,4-diisocyanate (TDI) induced occupational asthma mechanisms are not completelyknown. The aim of the study was to evaluate the nitro-oxidative stress associated to experimental miceTDI induced asthma. It was used a model of mice experimental exposure to TDI for 10 days. The studygroups (n = 12) were: a negative control group with skin sensitization and intranasal challenge, performedwith saline; group with sensitization and challenge with the solvent; group withsensitization and challenge with TDI; groups with TDI and aminoguanidine (AG) (50 mg/kg/d i.p.) orNG-nitro-L-arginine methyl ester (NAME), (5 mg/kg/d i.p.) or arginine (ARG) (100 mg/kg/d i.p.) ortrolox (20 mg / kg / day ip). On the 11th day blood was collected by cardiac puncture, and nitro-oxidativestress was assessed by total oxidative status (TOS), total antioxidative capacity (TAC), oxidative stressindex (OSI) and serum nitrates and nitrites (NOx). TDI increased TOS, OSI and NOx andreduced TAC. The solvent did not influence any parameter. AG, NAME and Trolox reduced NOx, TOSand OSI. Experimental exposure of mice to TDI caused systemic nitro-oxidative stress, and NOxreduction and Trolox lowered the systemic nitro-oxidative stress.