Table of Contents
ISRN Endocrinology
Volume 2011, Article ID 832642, 10 pages
Research Article

Proteases in Plasma and Kidney of db/db Mice as Markers of Diabetes-Induced Nephropathy

1Department of Medical Biology, University of Tromsø, 9037 Tromsø, Norway
2Department of Pathology, Oslo University Hospital, Rikshospitalet, 0027 Oslo, Norway
3Kidney Section, Department of Internal Medicine, Oslo University Hospital, Rikshospitalet, 0027 Oslo, Norway
4Institute of Clinical Medicine, University of Tromsø, 9037 Tromsø, Norway
5Department of Nutrition, Institute for Basic Medical Sciences, University of Oslo, P.O. Box 1046 Blindern, 0316 Oslo, Norway

Received 26 April 2011; Accepted 31 May 2011

Academic Editors: Z. Canturk, Y. Combarnous, and V. Woo

Copyright © 2011 E. Hadler-Olsen et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Db/db mice are overweight, dyslipidemic and develop diabetic complications, relevant for similar complications in human type 2 diabetes. We have used db/db and db/+ control mice to investigate alterations in proteinase expression and activity in circulation and kidneys by SDS-PAGE zymography, electron microscopy, immunohistochemistry, Western blotting, and in situ zymography. Plasma from db/db mice contained larger amounts of serine proteinases compared to db/+ mice. Kidneys from the db/db mice had a significantly larger glomerular surface area and somewhat thicker glomerular basement membranes compared to the db/+ mice. Furthermore, kidney extracts from db/+ mice contained metalloproteinases with 𝑀 𝑟 of approximately 92000, compatible with MMP-9, not observed in db/db mice. These results indicate that higher levels of serine proteinases in plasma may serve as potential markers for kidney changes in db/db mice, whereas a decrease in MMP-9 in the kidney may be related to the glomerular changes.