Figure 4. Mitochondrial content under basal conditions in control, wt/ N370SGBA and N370SGBA/N370SGBA neurospheres was assessed by western blotting for the mitochondrial proteins VDAC1 (outer mitochondrial membrane), SDHA (inner mitochondrial membrane), and TFAM (matrix), normalized by β-actin content. All markers tended to increase in N370SGBA/N370SGBA neurospheres in basal conditions, when compared to control lines (A) (SDHA was significant). As expected in control lines, protein levels of VDAC1, SDHA and TFAM and ATP levels decreased following CCCP treatment for 24 hours (B and C). Despite an apparent increase in mitochondrial mass in untreated conditions, ATP levels remained unchanged in wt/N370SGBA and N370SGBA/N370SGBA neurospheres (C). Mitochondrial markers of wt/N370SGBA did not show a marked response to CCCP uncoupling, in fact, TFAM significantly increased in the heterozygous lines and the decrease in ATP levels were not so pronounced (B and C) and ATP levels of homozygous N370SGBA/N370SGBA neurospheres showed a null response to CCCP uncoupling. All of the above data suggest that mitochondrial function may be impaired in GBA mutant neurospheres. AU: arbitrary units. Thin line indicates p value <0.05. Results are expressed by mean± SEM.