| First Author | Brähler S | Year | 2012 |
| Journal | Am J Physiol Renal Physiol | Volume | 303 |
| Issue | 10 | Pages | F1473-85 |
| PubMed ID | 22975019 | Mgi Jnum | J:190128 |
| Mgi Id | MGI:5448106 | Doi | 10.1152/ajprenal.00031.2012 |
| Citation | Brahler S, et al. (2012) Intrinsic proinflammatory signaling in podocytes contributes to podocyte damage and prolonged proteinuria. Am J Physiol Renal Physiol 303(10):F1473-85 |
| abstractText | Inflammation conveys the development of glomerular injury and is a major cause of progressive kidney disease. NF-kappaB signaling is among the most important regulators of proinflammatory signaling. Its role in podocytes, the epithelial cells at the kidney filtration barrier, is poorly understood. Here, we inhibited NF-kappaB signaling in podocytes by specific ablation of the NF-kappaB essential modulator (NEMO, IKKgamma). Podocyte-specific NEMO-deficient mice (NEMO(pko)) were viable and did not show proteinuria or overt changes in kidney morphology. After induction of glomerulonephritis, both NEMO(pko) and control mice developed significant proteinuria. However, NEMO(pko) mice recovered much faster, showing rapid remission of proteinuria and restoration of podocyte morphology. Interestingly, quantification of infiltrating macrophages, T-lymphocytes, and granulocytes at day 7 revealed no significant difference between wild-type and NEMO(pko). To further investigate the underlying mechanisms, we created a stable NEMO knockdown mouse podocyte cell line. Again, no overt changes in morphology were observed. Translocation of NF-kappaB to the nucleus after stimulation with TNFalpha or IL-1 was sufficiently inhibited. Moreover, secretion of proinflammatory chemokines from podocytes after stimulation with TNFalpha or IL-1 was significantly reduced in NEMO-deficient podocytes and in glomerular samples obtained at day 7 after induction of nephrotoxic nephritis. Collectively, these results show that proinflammatory activity of NF-kappaB in podocytes aggravates proteinuria in experimental glomerulonephritis in mice. Based on these data, it may be speculated that immunosuppressive drugs may not only target professional immune cells but also podocytes directly to convey their beneficial effects in various types of glomerulonephritis. |
