Chromogranin A (CGA)-derived polypeptide (CGA47–66) inhibits TNF-α-induced vascular endothelial hyper-permeability through SOC-related Ca2+ signaling
Autor: | Li Luo, Tao Xiang, Yan Zeng, Xiaoying Chen, Shan Xu, Shuke Liu, Siyi Liu, Nina Gu, Fu Wei, Dan Zhang |
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Rok vydání: | 2020 |
Předmět: |
medicine.diagnostic_test
biology Physiology Chemistry Chromogranin A 030209 endocrinology & metabolism Cell morphology Biochemistry Molecular biology TRPC4 Endothelial stem cell TRPC1 03 medical and health sciences Cellular and Molecular Neuroscience 0302 clinical medicine Endocrinology Western blot medicine biology.protein Phosphorylation Tumor necrosis factor alpha 030217 neurology & neurosurgery |
Zdroj: | Peptides. 131:170297 |
ISSN: | 0196-9781 |
Popis: | CGA1−78 (Vasostatin-1, VS-1) a N-terminal Chromogranin A (CGA)-derived peptide, has been shown to have a protective effect against TNF-α-induced impairment of endothelial cell integrity. However, the mechanisms of this effect have not yet been clarified. CGA47−66 (Chromofungin, CHR) is an important bioactive fragment of CGA1−78. The present study aims to explore the protective effects of CHR on the vascular endothelial cell barrier response to TNF-α and its related Ca2+ signaling mechanisms. EA.hy926 cells were used as a vascular endothelial culture model. The synthetic peptides CHR and CGA4−16 were assessed for their ability to suppress TNF-α-induced EA.hy926 cells hyper-permeability through Transwell® and TEER assays. Changes in [Ca2+]i were measured through confocal laser scanning microscopy. SOC channel currents (Isoc) were measured via patch-clamp analysis. RT-PCR and western blot were used to analyze mRNA and protein expression of the transient receptor potential channels TRPC1 and TRPC4, respectively. FITC and rhodamine-phalloidin fluorescence were used to assess cell morphology and the distribution of MyPT-1 and F-actin. Compared to untreated cells, TNF-α increased the permeability of EA.hy926 cells that was inhibited by pre-treatment with CHR (10–1000 nM) in concentration-dependent manner, and the effect was most obvious at 100 nM, but CGA4−16 (100 nM) had no effect. TNF-α treatment increased the phosphorylation of MyPT-1 and stress fiber formation. CHR (10–1000 nM) pretreatment inhibited the cytoskeletal rearrangements and increased [Ca2+]i in response to TNF-α treatment. CHR also reduced TRPC1 expression following TNF-α induction. Similar to SOC inhibitor 2-APB, CHR suppressed IP3 mediated SOC activation. These findings suggest that CHR inhibits TNF-α-induced Ca2+ influx and protects the barrier function of vascular endothelial cells, and that these effects are related to the inhibition of SOC and Ca2+ signaling by CHR. |
Databáze: | OpenAIRE |
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