Effect of hyperglycemia and PMA on eIF2α phosphorylation and splicing of XBP1 mRNA in neutrophil-like HL60 cells (dHL60).

<p>Hyperglycemia failed to modulate eIF2α phosphorylation (A; B) and splicing of XBP1 (C; D). Splicing of XBP1 mRNA was caused by PMA (1 μM) stimulus (1 and 4h) (C; D). [NG] normoglycemic media (5.5 mM of glucose); [MN] Mannitol enriched media (5.5 mM of glucose + 19.5 mM of mannitol); [HG] Hyperglycemic media (25 mM of glucose). Histogram (B) shows the mean ± S.E.M. optical density (OD) of the protein bands (A). γ Tubulin was used as loading control. (C) Complementary cDNA bands of unspliced XBP1 (uXBP1) (top band) and spliced (sXBP1) (bottom band). Results is representative of 3 independent experiments. [Tg] Positive control (1 μM Thapsigargin, 1h); [N1h] NG + 1h PMA; [M1h] MN + 1h PMA; [H1h] HG + 1h PMA; [N4h] NG + 4h PMA; [M4h] MN + 4h PMA; [H4h] HG + 4h PMA.