Fig. 3

Effects of Rhododendron leaf extracts on the mitochondrial membrane potential of IEC6 (a) and HaCaT (b) after 24 h incubation at 37 °C with three different concentrations (5, 50, and 500 μg/mL) of leaf extract as indicated. The intensity of MitoTracker® Red CMXRos signal reflects the accumulation of the dye within the mitochondrial matrix, which depends on an intact inner mitochondrial membrane potential, and thus on the metabolic activity of the cells. Values are given as mean ± standard deviations from three independent experiments, each performed in triplicates. Statistical evaluation was performed by one way ANOVA-analysis; levels of significance are indicated as *for p < 0.05