sentence: On the other hand , role of inflammation in AD and PD is characterized with subtle but important differences between these conditions ; in vivo models with mice have shown that A β oligomer accumulation in AD is related to TLR4 activity , which is in contrast with α - synuclein accumulation in PD , where the role of TLR4 is low or inexistent ( Noelker et al ., 2013 ; Forloni et al ., 2016 ; Calvo-Rodr í guez et al ., 2017 ) .