C57BL/6 mice were infected with T. cruzi, treated with PJ34 (12.5 mg/100-?l/mouse, intraperitoneally, twice a week for three weeks beginning at 45 days’ pi, and sacrificed at 150 days’ pi. (A) RT-qPCR evaluation of myocardial level of PARP1 mRNA, normalized to GAPDH mRNA (n ? 5 mice/group, triplicate observations per mouse). (B-E) Representative Western blot images of myocardial level of PARP1 with GAPDH loading control (n = 3 mice/group) and PAR levels in mice treated with increasing concentration of PJ34 (0–25 mg/kg) are shown in B & D, respectively. Densitometry analysis was performed for all Western blot gels from n ? 6 mice/group, and PARP1 and PAR levels (normalized to GAPDH levels) are shown in C & E, respectively. (F&G) Representative gel images (F, n = 3 mice/group) show myocardial levels of 10 kb mtDNA with 177-bp mtDNA and 96-bp GAPDH (nuDNA) fragments as controls. The PCR amplification was performed for 28 cycles. Densitometry analysis was performed on PCR gels representing n ? 6 mice/group, and density of the 10 kb mtDNA band, normalized against mtDNA and nuDNA fragments, is presented (G.a&b). (H-O) Bar graphs (n ? 5 mice/group, duplicate or triplicate observations per sample) show the myocardial (H-K & N) and plasma (L, M & O) levels of H2O2 (H), 3-nitrotyrosine (I), protein carbonyls (J&L), lipid hydroperoxides (K&M) and antioxidant capacity (N&O). (P) Myocardial parasite burden in chronically infected (± PJ34 treatment) mice was determined by qPCR amplification of Tc18SrDNA and normalized with GAPDH (n? 5 mice/group, three observations per mouse). Data in all bar graphs are plotted as mean value ± SEM, and statistical significance are marked as *infected vs. control and #infected/PJ34-treated vs. infected/untreated (*,#p<0.05, **,##p<0.01, ***,###p<0.01).