Research Paper Volume 8, Issue 10 pp 2355—2369

Figure 6. Proteasome inhibition rescues the expression of respiratory chain complexes in ROS-treated caveolin-1 null MEFs. Wild type and caveolin-1 null mouse embryonic fibroblasts (MEFs) were treated with sublethal doses of hydrogen peroxide (150 μM) for 2 hours in the presence or absence of 0.1 μM MG-132. Cells were then recovered in complete medium for 7 days in the presence or absence of 0.1 μM MG-132. Untreated cells (-H₂O₂) were used as control. (A) Total expression of complex I, complex II, complex III and complex IV was determined by immunoblotting analysis using specific antibody probes. Immunoblotting with anti-β-actin IgGs was performed as internal control. (B) Mitochondria were isolated and the expression of complex IV was determined using anti-complex IV IgGs. (C) Lactate production was quantified using the Lactate Assay Kit from Sigma-Aldrich (MAK064). Values were normalized to cell number. Values in (C) represent mean ± SEM; *P<0.001.