Figure 2: PEG-CAT protects hepatocytes from oxidative injury in a dose-dependent manner.

Hepatocytes were plated for 24 hours and treated with varying doses of PEG-CAT for 3 hours. Cells were then washed and treated with 400 μM H₂O₂ for 3 hours to induce oxidative stress. (A) Post-oxidative stress injury, PEG-CAT increased cell viability in a dose-dependent manner. Bar graphs show the mean absorbance relative to control ± SD from each of three independent cell cultures. Values in bar graphs not sharing a letter indicate a significant difference at P<0.05. (B) Mitochondrial membrane potential (MMP) was determined in hepatocytes by fluorescent JC-1 staining where the ratio of JC-1 red/green fluorescence represents the MMP. Data were obtained from three independent cell culture experiments. Bar graphs represent the mean ratio of JC-1 red/green fluorescence relative to the untreated control group ± SD. Values in bar graphs not sharing a letter indicate a significant difference at P<0.05. (C) Representative fluorescence micrographs of hepatocytes after JC-1 staining illustrate a dose-dependent increase in mitochondrial protection during oxidative stress. Red puncta represent JC-1 polymers/aggregates (normal membrane potential), while green puncta represent JC-1 monomers (depolarized MMP/damaged mitochondria).