The podocyte cytoskeleton in health and in disease

The podocyte is a key cell in the selective filtering action of the glomerular capillary wall. Podocyte injury is of pathogenetic and prognostic significance in human glomerular disease; podocyte repair and regeneration are important therapeutic targets. In particular, podocyte function is dependent on the cells' actin cytoskeleton: this maintains their complex structure. Alterations in the actin cytoskeleton arise from a variety of genetic and acquired causes. Therapeutic agents that are beneficial in proteinuric disease may act at least partly by restoring the cell shape via effects on the actin cytoskeleton. Recent studies of podocytes in vivo and in vitro are described, highlighting clinically relevant observations and those that help us understand the ways in which we may harness nature's own mechanisms to repair and/or renew these specialized glomerular cells, with a particular focus on their actin cytoskeleton. Drugs that have beneficial effects on podocytes can improve our ability to treat important renal diseases including diabetic nephropathy. Currently available agents can be applied in this way and the rapid progress in the study of podocytes is highlighting new therapeutic targets that can bring even more specificity.