ER stress response and XBP1 splicing in HCAECs subjected to FRH.

A. Ultrastructural analysis of HCAEC by TEM showing endoplasmic reticulum swelling over time. These pictures are representative of 10 pictures/ conditions, in 3 independent experiments. B. Expression kinetic of GRP78 et CHOP mRNAs over 24h during FRH. C. Expression kinetic of spliced (s)XBP1 and unspliced (u)XBP1 mRNA over 6 hours during FRH as compared to 37°C. D. Western Blot representative of XBP1s protein kinetic expression in HCAECs exposed to moderate hyperthermia (40°C vs 37°C). β-actin was used as a loading control. This blot is representative of 3 independent experiments. E. Quantitative analysis of the kinetic of XBP1s protein expression in HCAECs exposed to 37°C or 40°C (N = 3 experiments). F. RT-qPCR showing the spliced XBP1 (sXBP1) mRNA abundance in HCAEC cultured at 37°C or 40°C for 2h with or without B-I09 (20 µ M) (N = 3 experiments). *P < 0.05, **P < 0.01, ***P < 0.001.