6A), indicating that the loss of the protective effects of Wy-14,643 in this model is due to the lack of UCP2 and not PPARα itself

or other PPARα target genes. Wy-14,643 administration to Ucp2-null mice also did not restore mitochondrial GSH loss upon APAP treatment (Fig. 6B) nor fully suppressed the increase in p-JNK (Fig. 6C). These results suggest that the PPARα target gene UCP2 may be responsible for the protective effect of PPARα activators against APAP-induced toxicity. Ucp2-null mice could have subtle changes that render them resistant to the Wy-14,643 protection that are unrelated to UCP2. this website In order to further establish a role for UCP2 in Wy-14,643-induced protection against APAP hepatotoxicity, forced expression of the protein in livers of wildtype mice was carried out. Recombinant adenoviruses expressing UCP2 (Ad-Ucp2) were constructed and infused into the mouse livers prior to administration of APAP; UCP2 protein was robustly expressed in the livers of wildtype mice (Fig. 7, bottom right panel). Mice receiving the Ad-Ucp2 were protected against APAP-induced liver toxicity as revealed by H&E staining showing protection against liver necrosis (Fig. 7), lower serum AST and ALT enzyme activities (Fig. 8A), increased mitochondrial GSH (Fig. 8B), and lower p-JNK levels (Fig. 8C). This protection by Ad-Ucp2 was

evident at 24 hours post-APAP treatment as indicated by reduced levels of ALT enzyme (Fig. 8D). No protection was found when the control adenovirus expressing see more Cre recombinase was used and adenovirus itself did not appear to influence CYP2E1 expression Midostaurin (Supporting Fig. 6). ALT activity

values for Ad-Cre/APAP-treated mice ranged from 1.8 to 8.0 U/mL, whereas values from Ad-Ucp2/APAP-treated mice ranged from 0.06 to 0.7 U/mL. Even the highest Ad-Ucp2/APAP ALT activity value was still 2.6 times lower than the lowest Ad-Cre/APAP value. These data suggest that UCP2 can protect against APAP-induced hepatotoxicity and that it is a critical target gene responsible for PPARα-mediated protection during APAP-induced hepatotoxicity. The present study demonstrates a novel, protective role for PPARα during APAP-induced hepatotoxicity and sheds mechanistic insight into the importance of UCP2 in mediating these protective effects. When the experimental agonist Wy-14,643 was administered prior to a toxic dose of APAP, wildtype mice were completely protected against hepatotoxicity, as revealed by gross liver morphology, H&E-stained liver sections showing no significant liver damage, and low serum AST and ALT enzyme levels. In addition, livers from mice pretreated with Wy-14,643 prior to APAP had decreased oxidative stress, as revealed by lower H2O2 levels and higher GSH levels compared with livers from mice only treated with a toxic dose of APAP at 6 hours. Interestingly, Wy-14,643-treated mice exhibited a rapid reduction of GSH levels at 2 hours post-APAP treatment.