The acute phase response (APR) has been shown to alter expression and activity of biotransformation enzymes, such as the phase I cytochromes P450 and phase II glutathione s-transferases (GSTs). The cytochromes P450 and GSTs are expressed abundantly and colocalized to non-neuronal cells of the olfactory mucosa. Previous studies indicate that olfactory cytochromes P450 expression and activity is altered during periods of localized inflammation and infection. Little is understood, however, about the influence of the APR on olfactory GST enzymes. This study investigated effects of the APR on olfactory GST isozymes expression and activity in mouse olfactory mucosa after 24-hr treatment with the acute phase inducer, polyinosinic: polycytidylic acid (polyIC). Western blot analysis using antibodies directed against specific GST isoforms α (A1-1), μ (M1-1), and π (P1-1) demonstrated that their expression was unaltered by polyIC treatment. In contrast, olfactory P450 2E1 expression was significantly decreased. Enzymatic activity of the olfactory GSTs toward the general substrate, 1-chloro-2,4-dinitrobenzene (CDNB) was unchanged during the APR. Analysis of olfactory glutathione content during the APR showed that it was also unaffected by polyIC. The insensitivity of these olfactory GST isoforms during the APR may play a significant role toward limiting the impact of infection and inflammation on the olfactory system.

Helicoverpa armigera is a polyphagous pest. Due to excessive use of insecticides, the field populations of H. armigera have become resistant to synthetic pyrethroids by one or combination of three mechanisms / reduced penetration through the cuticle, decreased nerve sensitivity and enhanced metabolism by the detoxification enzymes especially glutathione S-transferases. In this study, gut sections of H. armigera were obtained from Adana and Antalya field populations and susceptible populations from Israel. Each gut section was homogenized separately in 1.0 ml, 40 mM and pH 7.5 phosphate buffers. GST activity was determined using CDNB as substrate. Product formation linearly increased up to 29.5&micro / g proteins in 20mM, pH 7.5 phosphate buffers. Maximum reaction rate was reached at 30&amp / #9702 / C. The Vmax and Km values for GST towards CDNB and GSH were calculated with Lineweaver-Burk and Eadie-Scatchard plots as CDNB Vmax / 6.54&micro / mol/min/mg, 6.35&micro / mol/min/mg , Km / 0.29mM, 0.28mM ,respectively and as GSH Vmax / 6.42&micro / mol/min/mg, 6.65&micro / mol/min/mg, Km / 0.22mM, 0.23mM, respectively. Cytosolic GST activity of each individual from Adana, Antalya and susceptible populations were determined under optimized conditions. The mean of GST activity in Adana population (n=50) and Antalya population (n=50) were found 7.824&micro / mol/min/mg and 9.518&micro / mol/min/mg, respectively. The mean of GST activity in susceptible population (n=50) was determined as 3.272&micro / mol/min/mg. According to these results, GST activities of Adana and Antalya field populations&rsquo / showed statistically significant increase (p&lt / 0.05) than susceptible H. armigera populations with ANOVA method. In addition, Antalya population showed statistically increase (p&lt / 0.05) GST activity than Adana.

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