Unique cellular and mitochondrial defects mediate FK506-induced islet β-cell dysfunction

Nassir Rostambeigi, Ian R. Lanza, Petras P. Dzeja, Michael C. Deeds, Brian A. Irving, Honey V. Reddi, Pranathi Madde, Song Zhang, Yan W. Asmann, Jarett M. Anderson, Jill M. Schimke, K. Sreekumaran Nair, Norman L. Eberhardt, Yogish C. Kudva

Research output: Contribution to journalArticlepeer-review

38 Scopus citations


Objective. To determine biological mechanisms involved in posttransplantation diabetes mellitus caused by the immunosuppressant tacrolimus (FK506). Methods. INS-1 cells and isolated rat islets were incubated with vehicle or FK506 and harvested at 24-hr intervals. Cells were assessed for viability, apoptosis, proliferation, cell insulin secretion, and content. Gene expression studies by microarray analysis, quantitative polymerase chain reaction, and motifADE analysis of the microarray data identified potential FK506-mediated pathways and regulatory motifs. Mitochondrial functions, including cell respiration, mitochondrial content, and bioenergetics were assessed. Results. Cell replication, viability, insulin secretion, oxygen consumption, and mitochondrial content were decreased (P<0.05) 1.2-, 1.27-, 1.77-, 1.32-, and 1.43-fold, respectively, after 48-hr FK506 treatment. Differences increased with time. FK506 (50 ng/mL) and cyclosporine A (800 ng/mL) had comparable effects. FK506 significantly decreased mitochondrial content and mitochondrial bioenergetics and showed a trend toward decreased oxygen consumption in isolated islets. Cell apoptosis and proliferation, mitochondrial DNA copy number, and ATP:ADP ratios were not significantly affected. Pathway analysis of microarray data showed FK506 modification of pathways involving ATP metabolism, membrane trafficking, and cytoskeleton remodeling. PGC1-α mRNA was down-regulated by FK506. MotifADE identified nuclear factor of activated T-cells, an important mediator of β-cell survival and function, as a potential factor mediating both up- and down-regulation of gene expression. Conclusions. At pharmacologically relevant concentrations, FK506 decreases insulin secretion and reduces mitochondrial density and function without changing apoptosis rates, suggesting that posttransplantation diabetes induced by FK506 may be mediated by its effects on mitochondrial function.

Original languageEnglish (US)
Pages (from-to)615-623
Number of pages9
Issue number6
StatePublished - Mar 27 2011


  • FK506
  • Insulin secretion
  • Islet toxicity
  • Mitochondrial DNA
  • Mitochondrial density
  • MotifADE

ASJC Scopus subject areas

  • Transplantation


Dive into the research topics of 'Unique cellular and mitochondrial defects mediate FK506-induced islet β-cell dysfunction'. Together they form a unique fingerprint.

Cite this