Comparison of mitochondrial levels of ROS and mtDNA base lesions in ZLN, ZOF, ZOF+mt-tat-EndoIII, and ZLN+mt-tat-ExoIII groups (n=3–4 per group). A: When normalized to the MitoSox fluorescence signals were comparable in ZOF and ZOF+mt-tat-EndoIII, but were 1.6±0.1 fold higher in ZLN+mt-tat-ExoIII compared to ZLN (P<0.05). B: mtDNA lesion frequencies in all groups. In ZLN (n=4) lesion frequency was not different than zero, but was significantly elevated in ZOF rats (n=5, P<0.05). ZLN+mt-tat-ExoIII (n=5) had a higher base lesion frequency than ZLN or ZOF+mt-tat-EndoIII (P<0.05, n=7). ZOF+mt-tat-EndoIII did not have a lesion frequency different than zero, and the average was significantly less than ZOF (P<0.05). Values are mean ± standard deviation. *P<0.05