epidermal-growth-factor and Glomerulosclerosis--Focal-Segmental

Mesenchymal stem cells (MSCs) have been shown to improve the outcome of acute renal injury models; but whether MSCs can delay renal failure in chronic kidney disease (CKD) remains unclear. In the present study, the were cultured in media containing various concentrations of basic fibroblast growth factor, epidermal growth factor and ascorbic acid 2-phosphate to investigate whether hepatocyte growth factor (HGF) secretion could be increased by the stimulation of these growth factors. Then, TGF-β1-treated renal interstitial fibroblast (NRK-49F), renal proximal tubular cells (NRK-52E) and podocytes were co-cultured with conditioned MSCs in the absence or presence of ascorbic acid 2-phosphate to quantify the protective effects of conditioned MSCs on renal cells. Moreover, male Sprague-Dawley rats were treated with 1 × 10(6) conditioned MSCs immediately after 5/6 nephrectomy and every other week through the tail vein for 14 weeks. It was found that basic fibroblast growth factor, epidermal growth factor and ascorbic acid 2-phosphate promoted HGF secretion in MSCs. Besides, conditioned MSCs were found to be protective against TGF-β1 induced epithelial-to-mesenchymal transition of NRK-52E and activation of NRK-49F cells. Furthermore, conditioned MSCs protected podocytes from TGF-β1-induced loss of synaptopodin, fibronectin induction, cell death and apoptosis. Rats transplanted with conditioned human MSCs had a significantly increase in creatinine clearance rate, decrease in glomerulosclerosis, interstitial fibrosis and increase in CD4(+)CD25(+)Foxp3(+) regulatory T cells counts in splenocytes. Together, our studies indicated that conditioned MSCs preserve renal function by their anti-fibrotic and anti-inflammatory effects. Transplantation of conditioned MSCs may be useful in treating CKD.

Topics: Animals; Apoptosis; Ascorbic Acid; CD4-Positive T-Lymphocytes; Cells, Cultured; Coculture Techniques; Creatinine; Disease Progression; Epidermal Growth Factor; Epithelial-Mesenchymal Transition; Female; Fibroblast Growth Factor 2; Fibronectins; Fibrosis; Glomerulosclerosis, Focal Segmental; Hepatocyte Growth Factor; Humans; Kidney; Kidney Tubules, Proximal; Lymphocyte Count; Male; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Microfilament Proteins; Middle Aged; Nephrectomy; Podocytes; Rats; Rats, Sprague-Dawley; Renal Insufficiency, Chronic; Transforming Growth Factor beta1; Young Adult

In this study, we attempted to determine whether heparin-binding epidermal growth factor-like growth factor (HB-EGF) was up-regulated in two chronic models of proteinuria.. Chronic passive Heymann nephritis (PHN) and puromycin aminonucleoside (PAN) models were induced in Sprague-Dawley rats. HB-EGF expression was studied by Northern blotting, in situ hybridization, and immunohistochemistry.. The chronic PAN model was associated with the development of glomerular lesions of focal glomerular sclerosis (FGS), severe interstitial fibrosis, and renal failure. Lesions of FGS were seen in approximately 80% of glomeruli at all time points, with a slight increase in the number of glomeruli showing extensive adhesion between 40 and 90 days. Northern blots of whole kidney tissue showed a 3- to 5.8-fold increased expression of HB-EGF mRNA in the chronic PAN group. Increased mRNA and protein were localized by in situ hybridization and immunohistochemistry to tubules, glomerular epithelial cells (GECs), and cells of Bowman's capsule. HB-EGF mRNA and protein were strongly expressed by epithelial cells involved in the formation of the lesions of FGS. By contrast, in chronic PHN, there was a small increase in HB-EGF, and the extensive lesions of FGS did not develop despite continued, heavy proteinuria.. These data suggest that HB-EGF may contribute to formation of the lesions of FGS, perhaps through stimulation of abortive mitogenesis in GECs or an adhesive interaction between transmembrane HB-EGF and the exposed glomerular basement membrane.

Topics: Actins; Animals; Creatinine; Disease Models, Animal; Epidermal Growth Factor; Glomerulonephritis; Glomerulosclerosis, Focal Segmental; Heparin-binding EGF-like Growth Factor; Immunohistochemistry; Intercellular Signaling Peptides and Proteins; Macrophages; Male; Proteinuria; Puromycin Aminonucleoside; Rats; Rats, Sprague-Dawley; RNA, Messenger; Up-Regulation

Focal glomerular sclerosis was induced in rats by chronic injections of puromycin aminonucleoside (PAN) on Days 0, 27, 34, and 41 and by unilateral nephrectomy on Day 22. Rats were sacrificed on Days 0, 8, and 20 (acute phase) and on Days 48, 60, and 80 (sclerotic phase). The percentage of sclerosing glomeruli was 16.6% on Day 48 and increased significantly to 72.8% on Day 80. We examined glomerular mRNA levels for proliferating cell nuclear antigen (PCNA), platelet-derived growth factor (PDGF)-A and B chains, transforming growth factor (TGF)-beta, epidermal growth factor (EGF), insulin-like growth factor (IGF)-I, and basic fibroblast growth factor (bFGF) on Days 0, 8, 20, 48, 60, and 80. Although these growth factor mRNA levels showed little change in glomeruli until Day 20, all growth factor mRNA levels increased in glomeruli during the sclerotic phase of PAN nephrosis as glomerular sclerosis progressed. On Day 80, mRNA levels for PCNA, PDGF-A and B chains, TGF-beta, EGF, IGF-I, and bFGF increased 12-, 10-, 12-, 15-, 2-, 2-, and 8-fold, respectively, in the glomeruli of PAN-treated rats with marked glomerular sclerosis when compared with control rats. Unilateral nephrectomy without PAN administration did not cause glomerular sclerosis up to Day 80 and mRNA levels for PCNA, PDGF-A and -B chains, TGF-beta, EGF, IGF-I, and bFGF in this group were almost the same as those in the normal sham-operated group. These data suggest that changes in growth factor mRNA levels in glomeruli may contribute to the development of PAN-induced glomerular sclerosis.

Topics: Animals; Blotting, Northern; Epidermal Growth Factor; Fibroblast Growth Factor 2; Gene Expression; Glomerulosclerosis, Focal Segmental; Growth Substances; Insulin-Like Growth Factor I; Kidney Glomerulus; Male; Nuclear Proteins; Platelet-Derived Growth Factor; Proliferating Cell Nuclear Antigen; Proteinuria; Rats; Rats, Sprague-Dawley; RNA, Messenger; Transforming Growth Factor beta