Insulin Increases Expression of TRPC6 Channels in Podocytes by a Calcineurin-Dependent Pathway
| Autor: | Ying Liu, Xinming Li, Florian Thilo, Martin Tepel, Shengqiang Xia |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
Transcriptional Activation medicine.medical_specialty Physiology Calcineurin Pathway Calcineurin-pathway medicine.medical_treatment Biology Transient receptor potential channel lcsh:Physiology Cell Line lcsh:Biochemistry 03 medical and health sciences 0302 clinical medicine Downregulation and upregulation Internal medicine TRPC6 Cation Channel medicine Journal Article Humans Insulin lcsh:QD415-436 TRPC Cation Channels lcsh:QP1-981 Podocytes Calcineurin Research Support Non-U.S. Gov't Cell biology Up-Regulation Insulin receptor 030104 developmental biology Endocrinology 030220 oncology & carcinogenesis biology.protein Signal transduction Signal Transduction |
| Zdroj: | Xia, S, Liu, Y, Li, X, Thilo, F & Tepel, M 2016, ' Insulin Increases Expression of TRPC6 Channels in Podocytes by a Calcineurin-Dependent Pathway ', Cellular Physiology and Biochemistry, vol. 38, no. 2, pp. 659-669 . https://doi.org/10.1159/000438658 Cellular Physiology and Biochemistry, Vol 38, Iss 2, Pp 659-669 (2016) |
| Popis: | BACKGROUND/AIMS: Insulin signaling to podocytes is relevant for the function of the glomerulus. Now, we tested the hypothesis that insulin increases the surface expression of canonical transient receptor potential canonical type 6 (TRPC6) channels in podocytes by a calcineurin-dependent pathway.METHODS: We used quantitative RT-PCR, immunoblotting, immunofluorescence and fluorescence spectrophotometry in cultured podocytes. Activation of Nuclear Factor of Activated T-cells (NFATc1) was measured using a specific calorimetric assay.RESULTS: Insulin increased the expression of TRPC6 transcripts and protein in podocytes. Insulin increased TRPC6 transcripts in a time and dose-dependent manner. The insulin-induced elevation of TRPC6 transcripts was blocked in the presence of tacrolimus, cyclosporine A, and NFAT-inhibitor (each p < 0.01 by ANOVA and Bonferroni's multiple comparison test). Transcripts of NOX4, another target gene of the calcineurin-NFAT pathway, were affected in a similar way. Immunoblotting showed that the administration of 100 nmol/L insulin increased TRPC6-proteins 2-fold within 48 hours. Insulin increased the activity of NFATc1 in nuclear extracts (p < 0.001) whereas tacrolimus, cyclosporine A, and NFAT-inhibitor blocked that insulin effect (p < 0.001; two way ANOVA). Immunofluorescence showed that insulin increased TRPC6-expression on the cell surface. Fluorescence-spectrophotometry and manganese quench experiments indicated that the increased TRPC6-expression after insulin administration was accompanied by an elevated transplasmamembrane cation influx. Insulin-stimulated surface expression of TRPC6 as well as transplasmamembrane cation influx could be reduced by pretreatment with tacrolimus.CONCLUSION: Insulin increases the expression of TRPC6 channels in podocytes by activation of the calcineurin-dependent pathway. |
| Databáze: | OpenAIRE |
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