3.2 SARS-CoV-2 induces inhibition of mitochondrial function and nuclear condensation in leukocytes of COVID-19 patients.
Mitochondrial function is assessed by staining with TMRM and were contrasted with nuclei stained with Hoechst in leukocytes. TMRM fluorescence was diminished in COVID-19 patients (viremia and severe sepsis with MODS), the former indicating a reduction in ΔΨm, are show in Fig. 2. The basal levels of mitochondrial function were 70780±5132 in relative units. Regarding mitochondrial function in the viremia group a 44% function was observed (31171±4449), while the MODS group presented a percentage of 67.5% (47785±4005) compared to the control, representing an inhibition of 66% (p<0.01) and 32.4% (p<0.05) respectively. Regarding the non-COVID MODS group, a significant inhibition of mitochondrial function of 23.2% was observed compared to the control (Figure 2A).
In regard to nuclear condensation by count of cells with the highest staining for Hoechst are show in Fig. 3. In the control group, an average number of 11.6 cells with the highest fluorescents was observed, while the COVID groups (viremia and MODS) showed an increase in nuclear condensation of 31 (165.6%) and 63 (442.7%) cells respectively (p<0.01). While the MODS group not positive for COVID also showed an increase in the number of cells with nuclear condensation (26.3 cells; 126.7% above of control) (Fig. 3A).
On the other hand, the graphs of correlation between peroxide levels and mitochondrial function are presented (Fig. 2B) and the correlation of peroxide levels and nuclear condensation (Fig. 3B), determined in the leukocytes of patients with COVID -19. It should be noted that a correlation was found between the parameters of r = 0.84 (Fig. 2B) and r = 0.90 (Fig. 3B).