Beta amyloid and hyperphosphorylated tau deposits in the pancreas in type 2 diabetes

Strong epidemiologic evidence suggests an association between Alzheimer disease (AD) and type 2 diabetes To determine if amyloid beta (A beta) and hyperphosphorylated tau occurs in type 2 diabetes, pancreas tissues from 21 autopsy cases (10 type 2 diabetes and 11 controls) were analyzed APP and tau mRNAs were identified in human pancreas and in cultured insulinoma beta cells (INS-I) by RT-PCR Prominent APP and tau bands were detected by Western blotting in pancreatic extracts Aggregated A beta, hyperphosphorylated tau, ubiquitin, apolipoprotein E. apolipoprotein(a), IBI/JIP-1 and JNK1 were detected in Langerhans islets in type 2 diabetic patients A beta was co-localized with amylin in islet amyloid deposits. In situ beta sheet formation of islet amylold deposits was shown by infrared microspectroscopy (SIRMS) LPS increased APP in non-neuronal cells as well We conclude that A beta deposits and hyperphosphorylated tau are also associated with type 2 diabetes, highlighting common pathogenetic features in neurodegenerative disorders, including AD and type 2 diabetes and suggesting that A beta deposits and hyperphosphorylated tau may also occur in other organs than the brain (C) 2008 Elsevier Inc All rights reserved