FIG 1.

(a) Mitochondrial and cell toxicity analysis in PBMC of patients after 28 consecutive days of linezolid treatment. Results are expressed as the percentage of variation of each parameter after linezolid treatment with respect to the baseline. Prot, protein. *, P < 0.05; **, P < 0.001. Linezolid treatment significantly reduced mitochondrial protein levels in PBMC by 55.72% ± 7.74% (P < 0.001), mtCIV activity by 52.86% ± 5.34% (P < 0.001), and mitochondrial mass by 26.23% ± 15.18% (P < 0.05). The unexpected increments in mtDNA content (59.92% ± 21.18%) (P < 0.05), mtRNA levels (23.76% ± 19.21%), and ATPase-α levels (41.14% ± 26.07%) may indicate homeostatic compensatory mechanisms to overcome linezolid toxicity. Despite the development of these strategies, linezolid therapy trended to impair cell viability, though not significantly, by enhancing apoptosis and increasing the caspase 3/VDAC ratio by 12.53% ± 14.56%. (b) Western blot quantification of mitochondrial protein synthesis (COXII) with respect to cytoplasmic protein VDAC in PBMC before and after linezolid treatment.