Figure 5.

TMAO induces endoplasmic reticulum (ER) stress by activating the PERK pathway of the unfolded protein response (UPR). (A) Hippocampal slices were incubated in ACSF with either 0.03% DMSO (vehicle) or TMAO (50 μM) for 4 h and then the lysates were subjected to immunoblotting. Representative western blot showing p-PERK, PERK, p-eIF2α, eIF2α, ATF4, p-CREB, and CREB levels normalized to α-tubulin. (B) Western blot analysis of p-PERK, PERK, p-eIF2α, eIF2α, ATF4, p-CREB, and CREB in hippocampal lysates from control, 3×Tg-AD and db/db mice aged 8 months. α-tubulin was used as an internal housekeeping protein control. Results are shown as mean ± SEM of three mice per group. **p < 0.01, ***p < 0.001.