Figure 4.

Proximal tubule-specific loss of Sirt6 increases UUO-induced extracellular matrix deposition. (A) Representative sections of kidneys from sham- and UUO-operated Sirt6^flox/flox; Ggt1-Cre^- (WT) and Sirt6^flox/flox; Ggt1-Cre⁺ (PT-Sirt6KO) mice were stained with Picro Sirius red. Scale bar = 100 μm. The bar graph shows Picro Sirius red-positive areas (%) in the sham and UUO kidneys from ten randomly chosen, non-overlapping fields at a magnification of 100× (n = 15 per group). (B) Representative Western blot analysis of type I collagen and CTGF expression in the kidneys from sham- and UUO-operated Sirt6^flox/flox; Ggt1-Cre^- (WT) and Sirt6^flox/flox; Ggt1-Cre⁺ (PT-Sirt6KO) mice. The bar graph shows the densitometric quantification presented as the relative ratio of each protein to β-actin. The relative ratio measured in the kidneys from sham-operated WT mice is arbitrarily presented as 1. Data are expressed as mean ± SD. ***, p < 0.001 versus WT sham or PT-Sirt6KO sham; ##, p < 0.01 and ###, p < 0.001 versus WT UUO. Sham, sham-operated mice; UUO, unilateral ureteral obstruction; WT, wild-type; PT-Sirt6KO, proximal tubule-specific Sirt6 knockout; CTGF, connective tissue growth factor.