sentence: Seven PPAR responsible elements were identified by in silico analysis and the specific agonist GEM led to enrichment of PPARalpha and its heterodimer Retinoid X Receptor alpha ( RXRalpha ) binding partner at two direct repeat 1 PPAR responsive elements ( PPRE ) located in the ADAM10 promoter in wild type , but not in PPARalpha knock-out hippocampal neurons .