Fig. 5.

Exposure of human embryonic stem cell (hESC)-derived neurons to propofol altered the expression of the mitochondrial fission-related protein and did not affect mitochondrial fusion. (A) Western blotting was used to assess the expression of dynamin-related protein 1 (Drp1), a protein responsible for inducing mitochondrial fission. Drp1 becomes activated when phosphorylated at the Ser616 position. Exposure of hESC-derived neurons to 6 hours of 20 μg/mL propofol significantly increased the expression of activated Drp1 (pDrp1 Ser 616). The data are presented as a ratio of pDrp1/total Drp1 and as a percent of the control (B) Western blotting was also used to assess the expression of mitofusion 1 and 2 (MFN1 and MFN2) and optic atrophy 1 (OPA1), proteins all responsible for inducing mitochondrial fusion (a). Following 6 hours of exposure to 20 μg/mL propofol, there was no significant change in the expression of MFN1, MFN2 or OPA1 when compared to control treated cells (b–d), indicating that propofol exposure does not significantly affect mitochondrial fusion. These data are presented as a percent of the control group following normalization to COX IV, a marker of the inner mitochondrial membrane. (**P < 0.01, n = 5/group). NS = Not significant.