HSP90AA1 and neurodegenerative disease: It was mentioned earlier (Sections 2.2 and 3.4) thatcertain 17- and 19-alkoxy derivatives of GA were neuroprotective,35 and the involvement of Hsp90 in neurologicaldisorders has been widely investigated of late.123 Some Hsp90 client proteins are believed to play an importantrole in protein aggregation underlying neurodegenerative diseases,20−22 examples of which include α-synuclein, tau, and Huntingtinproteins.