Fig. 4

Evaluation of oxidative stress in I/R-injured skin flaps after PRP treatment. Tissue samples were obtained from each treatment group, weighed, homogenized, and subjected to biochemical assays for (A) MDA content, (B) NO level, (C) SOD activity, and (D) GSH-Px activity. Results were presented as nanomole per gram fresh weight, micromole per gram fresh weight, or unit per gram fresh weight. Error bars represent the means ± SD (n = 4). Student’s t-test for comparison between two groups, and one-way ANOVA followed by the Tukey–Kramer post hoc test for comparison among multiple groups were used. *p < 0.05 vs. the corresponding PBS control, ^&p < 0.05 vs. the value in pre-PRP group after I/R insult, ^#p < 0.05 vs. the value in mid-PRP group after I/R insult. In each bargraph, the white bars from left to right represented treatment with PBS without I/R insult, before I/R insult, before reperfusion, or after reperfusion, respectively; the slash bar represented treatment with PRP without I/R insult; the black bar represented treatment with PRP before I/R insult; the dark grey bar represented treatment with PRP before reperfusion; the light grey bar represented treatment with PRP after reperfusion