Fig. 7.

Reversal of β-alanine-mediated mitochondrial toxicity by taurine treatment. a The upper panel shows representative confocal microscopic images of fibroblasts treated initially for 48 h with β-alanine followed by a 48 h incubation with normal β-alanine-free medium. In the lower panel, fibroblasts were treated initially for 48 h with β-alanine and then placed in medium containing taurine for 48 h. All cells were loaded with MitoSox (10 μM) and MitoTracker Green (200 nM). In the upper left hand panel is shown MitoSox fluorescence (red) following the exposure of β-alanine-treated fibroblasts to normal medium for 48 h. In the lower left hand panel is shown MitoSox fluorescence (red) of β-alanine-treated fibroblasts exposed for 48 h to taurine containing medium. In the upper middle and lower middle panels is shown MitoTracker green fluorescence of mitochondria from β-alanine-treated fibroblasts exposed for 48 h to normal medium or to taurine containing medium, respectively. In the upper left hand and lower left hand panels is shown a merged image of MitoSox and MitoTracker green fluorescence of mitochondria from β-alanine-treated fibroblasts exposed for 48 h to normal medium or to taurine containing medium, respectively. Taurine supplementation partially reversed the increase in MitoSox fluorescence mediated by β-alanine treatment. b Magnified, MitoTracker green fluorescent β-alanine-treated fibroblasts were exposed for 48 h to medium containing or lacking taurine. Taurine supplementation partially reversed mitochondrial fragmentation mediated by β-alanine treatment. c The distribution of mitochondrial length in fibroblasts treated initially for 48 h with β-alanine followed by a further 48 h incubation with normal medium. The distribution pattern is shifted to the left, indicating an increase in the number of mitochondria having reduced diameter. The mean length of mitochondria of β-alanine-treated fibroblasts exposed for 48 h to normal medium or to taurine containing medium were 1.81 ± 0.053 and 3.12 ± 0.095 μm, respectively