The growth and migration of cultured cells were quantified by using CL-Quant software to analyze time-lapse images in a Nikon BioStation CT. The real-time images of cell migration were monitored for 2 days. And also NRK-49F cells were stimulated with S1P after the addition of FTY720 (S1P 1, 3, 4, 5 agonist), or DMS (sphingosine kinase inhibitor) were evaluated. Results: S1P stimulated fibrosis of NRK-49F cells in a dose- and time-dependent manner as
previously observed, and induced morphological changes (elongation of the cell shape with spindle-like extension, increased migration) of the NRK-49F cells. Migration of NRK49F cells was accelerated and increase in a-SMA, COL1, COL4, TIMP1 and PAI1 expressions and decrease in E-cadherin expression were observed by addition of S1P. Antagonist and siRNA transfection to NRK-49F cells of Sphingosine 1-phosphate receptor-3 (S1PR-3) attenuated cell
growth and migration, Alectinib chemical structure in addition, the expression of fibrotic markers was also diminished by antagonist and siRNA transfection to NRK-49F cells of S1PR-3. And also in the presence of FTY720 and DMS, fibrosis and migration induced by S1P were suppressed. Conclusion: These results suggest that activation of S1P signaling mediated by S1PR-3 results in chronic pathological fibrosis, such as in chronic kidney disease (CKD). LEUNG JOSEPH C K, CHAN LORETTA Y Y, LIM AI ING, WONG DICKSON W L, LAI KAR NENG, TANG SYDNEY C W The University of Hong Kong, Hong Kong Introduction: Protein overload selleck induces apoptosis in proximal tubule epithelial cells (PTEC). We have recently shown that bone morphogenetic protein-7 (BMP-7) up-regulates the expression of cellular inhibitor of apoptosis 1 (cIAP1) and represses albumin-induced chemokines synthesis in kidney tubular epithelial cells (PTEC). In this study, we examined the effect of BMP-7 on albumin-induced apoptosis in PTEC. Methods: An in vitro PTEC culture model of albumin overload was used to examine the roles of BMP-7 on albumin-induced apoptosis. Either with Bay 11-7085 or without incubation with recombinant
human BMP-7, apoptosis in cultured PTEC exposed to albumin (5 mg/ml for 3 days) was determined using an in situ cell death detection kit and quantitated with a fluorometric TUNEL assay. Expression of genes and proteins of TNF-α, the pro-apoptotic bax, bad and anti-apoptotic bcl-xL, c-FLIP, were determined by quantitative RT-PCR, western blotting or ELISA. Caspase-8 activity was determined using a luminescent assay. Activation of the NF-kB p65 and p50 subunits in PTEC were quantitated by ELISA-based transcriptional factor assays and western blotting. Results: In cultured human PTECs, albumin significantly up-regulated the gene and protein expression of bax, bad but down-regulated bcl-xL and c-FLIP. Addition of BMP-7 further amplified these increased apoptotic and reduced anti-apoptotic proteins expression elicited by albumin.