Mitochondria are impaired in the adipocytes of type 2 diabetic mice

Diabetologia. 2006 Apr;49(4):784-91. doi: 10.1007/s00125-006-0170-2. Epub 2006 Feb 25.


Aims/hypothesis: The aim of this study was to confirm a link between mitochondrial dysfunction and type 2 diabetes.

Materials and methods: Cellular levels of mitochondrial proteins, cellular mitochondrial DNA content, and mitochondrial function and morphology were assessed by MitoTracker staining and electron microscopy, in white adipose tissue of 12-week-old male wild-type, obese (ob/ob), and diabetic (db/db) mice.

Results: Levels of mitochondrial proteins were found to be very similar in the livers and muscles of all the mice studied. However, levels were greatly decreased in the adipocytes of db/db mice, but not in those of the wild-type and ob/ob mice. Levels of mitochondrial DNA were also found to be considerably reduced in the adipocytes of db/db mice. MitoTracker staining and under electron microscopy revealed that the number of mitochondria was reduced in adipocytes of db/db mice. Respiration and fatty acid oxidation studies indicated mitochondrial dysfunction in adipocytes of db/db mice. Interestingly, there was an increase in mitochondria and mitochondrial protein production in adipocytes of db/db mice treated with rosiglitazone, an agent that enhances insulin sensitivity.

Conclusions/interpretation: Taken together, these data indicate that mitochondrial loss in adipose tissue is correlated with the development of type 2 diabetes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipocytes / drug effects
  • Adipocytes / metabolism*
  • Adipocytes / ultrastructure
  • Animals
  • DNA, Mitochondrial / genetics
  • Diabetes Mellitus, Type 2 / genetics
  • Diabetes Mellitus, Type 2 / metabolism*
  • Diabetes Mellitus, Type 2 / pathology
  • Female
  • Male
  • Mice
  • Microscopy, Electron
  • Mitochondria / drug effects
  • Mitochondria / metabolism*
  • Mitochondria / ultrastructure
  • Mitochondrial Proteins / biosynthesis
  • Mitochondrial Proteins / genetics
  • Rats
  • Rosiglitazone
  • Thiazolidinediones / pharmacology


  • DNA, Mitochondrial
  • Mitochondrial Proteins
  • Thiazolidinediones
  • Rosiglitazone