Fig. 5.

Reduced M. tuberculosis burden by simvastatin is associated with cholesterol-dependent nuclear translocation of TFEB. A: Representative immunoblots of TFEB in whole-cell lysates (left panel) and nuclear extracts (right panel) of THP1 cells uninfected or infected with M. tuberculosis for 6 days treated with DMSO as a solvent control or 100 nM simvastatin. Protein quantification and normalization relative to total protein or lamin B1, per lane, was performed using LI-COR Image Studio software. B: Immunoblot analysis of TFEB abundance (relative to total protein) in nuclear lysates of infected THP1 cells treated with 100 nM simvastatin in the absence or presence of soluble cholesterol (1.25 μg/ml). When total protein was used as loading control (panels A and B), only a portion of the membrane probed for total protein is shown. C: Effect of 7.5 nM Digoxin (TFEB activator) on the intracellular growth of M. tuberculosis in THP1 cells. Significance was tested by Student’s t-test: *P < 0.05; **P < 0.01; ns, not significant.