From the Facebook page of GreenMedInfo (like this page for interesting updates on published articles about natural substances related to medicine) I obtained the link to an article relating curcumin (in Portugal it is present in Açafrão) with positive results on AD (Alzheimer's Disease) published in 2006.
http://www.ncbi.nlm.nih.gov/pubmed/16988474 (original article - abstract only)
http://www.greenmedinfo.com/article/curcumin-appears-enhance-clearance-amyloid-beta-alzheimers-disease-patients (GreenMedInfo page)