Proteomic study of diabetic nephropathy

Pathogenesis of diabetic nephropathy (DN) is undoubtedly complex with elements of genetic disposition, hemodynamic changes and various cytokines orchestrated by prolonged hyperglycemia. Nakatani et al. used proteomic technique to study glomeruli from deceased patients who had DN. These glomeruli were laser microdissected from archived autopsy tissue preserved in formalin-fixed paraffin-embedded blocks. Among many overexpressed proteins related to urinary system diseases, nephronectin was identified for immunohistochemical study.


Nephronectin, a protein known to be involved in kidney development and extracellular matrix assembly, was expressed in glomeruli of diabetic patients significantly more than in those from non-diabetic patients. Glomeruli from patients with DN also expressed nephronectin more than those from diabetic patients without DN. More nephronectin expression related to more glomerulosclerosis.
The study identified one more protein involving in DN pathogenesis, though how it fits into the overall picture was unclear. Considering that the formalin-fixed paraffin-embedded tissue was available in large amount in pathology laboratories worldwide, proteomic study coupled with laser microdissection technique used in this study could lead to more studies of this archival tissue to come.