Glomerular filtration barrier.
OBJECTIVE
In 2008, more than 376 papers were published on the glomerular barrier. Most of them dealt with the podocyte and its role in kidney disease.


RESULTS
There is new information on signaling pathways that are utilized in podocytes during proteinuria. Interestingly, the glomerular endothelium, with its fenestrae and glycocalyx, seems to be important for the maintenance of an intact glomerular barrier. All new advances at the molecular level are compatible with a highly size and charge-selective glomerular membrane and refute the concept of a 'leaky' glomerular barrier with tubular retrieval of intact albumin. Still, the hypothesis has its advocates, keeping a stimulating 'charge debate' alive.


CONCLUSIONS
Glomerular diseases account for 90% of chronic kidney disease requiring dialysis and transplantation at an annual cost of $20 billion in the USA. In clinical practice, we lack specific treatment of these diseases, giving us plenty of room for improvement. Future research should be directed toward deeper understanding of the signaling pathways involved in different conditions of proteinuria, the cross-talk between cell types in the glomerulus, and the identification of novel targets for treatment of acquired kidney disease.
Haraldsson
Börje
B
Department of Molecular and Clinical Medicine - Nephrology, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden. borje.haraldsson@gu.se
Jeansson
Marie
M
D000818:Animals; D042783:Endothelial Cells / Q000502:physiology; D006801:Humans; D007678:Kidney Glomerulus / Q000378:metabolism*; D010539:Permeability; D050199:Podocytes / Q000502:physiology; D015398:Signal Transduction; D042461:Vascular Endothelial Growth Factor A / Q000502:physiology
D042461:Vascular Endothelial Growth Factor A