Differential Effects of Silibinin A on Mitochondrial Function in Neuronal PC12 and HepG2 Liver Cells

Figure 2

Comparison of mitochondrial function between untreated PC12 and untreated HepG2 cells. (a) Adenosine triphosphate (ATP) level of 10⁴ cells of both cell lines. (b) Mitochondrial membrane potential (MMP) level of cells of both cell lines. (c) Respiration of 10⁶ cells of both cell lines. Activity of the oxidative phosphorylation (OXPHOS) complexes was assessed via the addition of several substrates, inhibitors, or uncouplers. Which substance was added in which stage of the experiment is indicated by the placement of “+.” Dig = the addition of digitonin; CI_(L) = leak respiration of complex I; CI_(P) = coupled respiration using only complex I substrates; CI&CII_(P) = physiological respiration; CI&CII_(L) = leak respiration of complexes I and II; CI&CII_(E) = uncoupled respiration using maximum CI&CII activity; CII_(E) = uncoupled respiration using complex II substrates only; CIV_(E) = uncoupled respiration using only CIV after complex III inhibition and CIV activation using an electron donor. (d) Citrate synthase activity of 10⁶ cells. The procedure for all experiments was the same as that employed for experiments treating cells with SIL A or DMSO, but instead of an effector, the cell medium was used. Data are displayed as the . . Statistical significance was tested via Student’s -test (, , , and ).

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