[Role of tumor necrosis alpha in the regulation of extracellular matrix and proliferation of mesangial cells in nephrotoxic nephritis].

Acute and chronic stages of NTN are followed by infiltration of glomeruli with monocytes/macrophages having different location (lumen of capillaries in the acute stage and mesangial zone in the chronic one). TNF-alpha is one of the key factors of the NTN acute stage damaging glomerular structures and initiating production of matrix form of the main factor of the fibroblast growth and transforming growth factor beta. Accumulation of these cytokines in the matrix facilitated monocyte penetration in the mesangium zone in chronization. Interaction of the matrix-associated cytokines regulates proliferative and fibrogenic activity of the mesangial cells as well as production of TNF-alpha by monocytes/macrophages. A decrease of TNF-alpha level during a chronic stage of NTN results in a decrease of the mesangial cell ability to produce matrix-associated cytokines.