Small Interfering RNA Targeting Mitochondrial Calcium Uniporter Improves Cardiomyocyte Cell Viability in Hypoxia/Reoxygenation Injury by Reducing Calcium Overload

Figure 4

MCU silencing reduces significantly mitochondrial permeability transition by calcium overload. (a) Representative mitochondrial traces in permeabilized MCU-silenced cardiomyocytes using 2 μM safranin, after 7.5 μM Ca²⁺ addition. siRNA-Neg cardiomyocytes show no difference in compared to MCU-silenced cells at baseline. MCU-silenced cardiomyocytes were able to maintain significantly after 7.5 μM Ca²⁺ addition. Upon completion of the traces, 20 μM CCCP was added as uncoupling. (b) Semiquantitative analysis of after Ca²⁺ addition in transfected cardiomyocytes. versus siRNA-Neg, mean ± SEM, . (c) Representative mitochondrial safranin recordings in siRNA-Neg cardiomyocytes treated with 5 μM Ru₃₆₀ or 1 μM CsA before 7.5 μM Ca²⁺ pulse. (d) Semiquantitative analysis of in siRNA-Neg cardiomyocytes treated with Ru₃₆₀ or CsA. versus siRNA-Neg, mean ± SEM, . Upon completion of the registers, 20 μM CCCP was added as uncoupling. All semiquantitative data is normalized to 100% of untreated siRNA-Neg cardiomyocytes at basal conditions. AFU, arbitrary fluorescence units. versus siRNA-Neg.

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