Total RNA was isolated from primary hepatocytes, pancreatic islets, and hippocampal neurospheres, treated with 0.1% DMSO (control) or FK866 (200 nM for primary hepatocytes, and 10 nM for pancreatic islets and hippocampal neurospheres). Primary hepatocytes and pancreatic islets were isolated from 3 month-old C57BL/6J (B6) male mice (Jackson Laboratories). To determine transcriptional changes induced by FK866 treatment, microarray analyses were conducted using the Illumina Mouse Ref 8 whole genome microarrays (version 2). The background-subtracted raw microarray data were subjected to Z score transformation, and Z ratios were calculated as described previously 5 (link). All data were analyzed by the R statistical software package.