A study showed that PE increased mtDNA repair, ameliorated mitochondria respiratory function through the increase of RCC activity, attenuated ROS generation capacity together with a reduction of Aβ1-42 peptide levels, and correlated with an amelioration of cognitive function in the hippocampus from the APP/PS1 transgenic mouse model of AD (Bo et al., 2014). This evidence concerns the gene PSEN1 and Alzheimer disease.