Fig. 3
Differential effect of tigecycline/tetracycline on mtDNA levels and biogenesis. After treatment with Tig/Tet at respective IC50 concentrations for 24 and 48 h, total DNA and RNA were extracted for A measuring mtDNA copy number and B-C mRNA expression of mitochondrial biogenesis markers, respectively, by TB green-based qPCR. A Relative mtDNA copy number was determined by quantifying the mt-tRNA leucine 1 gene copy number and normalized with nuclear 18s rRNA copy number in different cells upon treatment with tigecycline Aa and tetracycline Ab. The cells were treated with B tigecycline and C tetracycline for 24 and 48h and the relative mRNA expression of mitochondrial biogenesis markers a PGC1-α, b NRF1, c NRF2, and d TFAM, normalized to β-actin expression, was evaluated by RT-qPCR. Data are the Mean ± SD of three replicates from a representative experiment normalized to the respective control. *P<0.05, **P<0.01 and ***P<0.001. Abbreviations: PGC1-α, peroxisome proliferator, activated receptor γ coactivator α; NRF, nuclear respiratory factor; TFAM, mitochondrial transcription factor A; mtDNA, mitochondrial DNA; qPCR, quantitative polymerase chain reaction; RT-reverse transcription