1. ER Stress via CHOP Pathway is Involved in FK506-Induced Apoptosis in Rat Fibroblasts.
- Author
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Tang J, Ge Y, Yang L, Xu X, Sui T, Ge D, Que J, and Cao X
- Subjects
- Animals, Animals, Newborn, Apoptosis drug effects, Apoptosis genetics, Endoplasmic Reticulum drug effects, Endoplasmic Reticulum metabolism, Endoplasmic Reticulum Stress drug effects, Fibroblasts cytology, Fibroblasts drug effects, Gene Expression Regulation, Primary Cell Culture, RNA, Small Interfering genetics, RNA, Small Interfering metabolism, Rats, Rats, Sprague-Dawley, Ryanodine Receptor Calcium Release Channel genetics, Ryanodine Receptor Calcium Release Channel metabolism, Signal Transduction, Tacrolimus Binding Proteins metabolism, Transcription Factor CHOP antagonists & inhibitors, Transcription Factor CHOP metabolism, Calcineurin Inhibitors pharmacology, Endoplasmic Reticulum Stress genetics, Fibroblasts metabolism, Tacrolimus pharmacology, Tacrolimus Binding Proteins genetics, Transcription Factor CHOP genetics
- Abstract
Background/aims: Hypertrophic scars (HS) formation results from reduced apoptosis and increased proliferation of fibroblasts. Therefore, apoptosis of fibroblasts is a key target for the development of novel therapeutic strategies for HS. Previous reports demonstrated that FK506 could attenuate scar formation in vivo and FK506 could also induce endoplasmic reticulum stress (ER stress). However, the effects of FK506 on ER stress-mediated apoptosis in fibroblasts remain unclear., Methods: Rat skin fibroblasts were used in the study. Cell viability was examined using cell counting Kit-8. Apoptosis was detected by Annexin V/Propidium Iodide Double Staining. Gene silencing was performed using Small Interfering RNAs (siRNAs) or via lentiviral infection. The expression of apoptosis-related proteins was determined via Western blot. Interaction between proteins was explored by co-immunoprecipitation., Results: FK506 significantly reduced cell viability and induced apoptosis in fibroblasts. Interestingly, ER stress was also activated after FK506 treatment. We further demonstrated that FK506-induced apoptosis was mediated by ER stress via activating CHOP, evidenced by decreased apoptosis after inhibition of ER stress using TUDCA or silencing expression of CHOP. Furthermore, Co-immunoprecipitation results indicated that treatment of FK506 induced disassociation of FKBP12.6 from RyR2 and its translocation from ER membrane to cytosol, consequently promoting ER stress-mediated apoptosis., Conclusion: FK506-induced fibroblasts apoptosis was mediated by ER stress via CHOP signaling pathway., (© 2016 The Author(s) Published by S. Karger AG, Basel.)
- Published
- 2016
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