Figure 4.

Inhibition of mitochondrial MITF Serine 73 phosphorylation using U0126 affects mast cell degranulation and mitochondrial functions. Mast cells were stimulated with IgE-DNP and incubated either with 20 µmol/L U0126 or DMSO as control and degranulation activity was assessed by measuring β-hexosaminidase release and cytokine (TNF-α, granzyme B) secretion using the ELISA assays in RBL cells (A–C) and BMMCs (D–F). Mitochondrial activity assay results are shown in (G) mitochondrial ATP, (H) Oxygen consumption rate with the increased pyruvate levels (I) and the decreased pyruvate dehydrogenase activity (J) in RBL cells. A two-tailed Student’s t-test was performed for all the assays. Results represent means ± SEMs (n = 4, **** p ≤ 0.0001; *** p ≤ 0.001; ** p ≤ 0.01; ns p > 0.05).