TLR4-SIRT3 Mechanism Modulates Mitochondrial and Redox Homeostasis and Promotes EPCs Recruitment and Survival

Figure 3

LPS induces mitochondrial superoxide generation through TLR4. MitoSOX-labeled (red) mitochondrial superoxide level was measured and calculated in EPCs ( per group, results were expressed as ). While low dose LPS (1 μg/mL) precondition reduced superoxide level in EPCs, the high dose (10 μg/mL) induced mitochondrial superoxide accumulation significantly, which can be alleviated to a great extent by TLR4-specific antagonist TAK-242 or reversed by SIRT3 overexpression (LetSIRT3). (a) Representative fluorescent images and (b) quantitative analysis of fluorescence intensity are shown here (, ). Cell nuclei are stained by DAPI. (Scale bars 100 μm). vs. control; vs. 1 μg/mL LPS; vs. 10 μg/mL LPS.

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