HSF1 and Alzheimer disease: To extend these observations to a neurodegenerative model of Aβ42 amyloid aggregation, we examined the expression levels of HSF1 and HSF1-P (phosphorylated at T142) [67] in brain homogenates of WT and AD mice (AβPP Tg) at three different ages (approximately 4 mo, 9 mo, and 16 mo old).