Figure 4. 5-azacytidine blocks injury-induced pathological vascular remodeling and neointima formation in a PTEN-dependent manner.
Male WT (Myh11-CreERT2;Rosa26-YFP) and SMC-specific PTEN iKO (PTENflox/flox-Myh11-CreERT2;Rosa26-YFP) mice received 1.5 μg tamoxifen injections i.p. for 7 consecutive days to induce PTEN knockout in PTEN iKO mice and YFP knock-in in both WT and PTEN iKO mice. The left carotid artery was ligated to induce vascular injury and neointima formation as described in Materials and Methods. Mice received 2 mg/kg 5-azacytidine or vehicle control i.p. injections 3x weekly for 3 weeks prior to tissue harvest. The right uninjured control and left injured carotid arteries were harvested three weeks post-injury, fixed in 4% PFA, and embedded in OCT. (A) Arterial sections were stained for hematoxylin (left panels), Movat’s pentachrome stain (middle panels), or Masson’s trichrome stain (right panels). Shown are representative stained images of injured left carotid arteries. (B&C) Percent stenosis (B) and adventitial remodeling (C) were measured using Image J, as described in Materials and Methods. (B) N=9 (WT vehicle), N=8 (WT 5-azacytidine), N=6 PTEN iKO vehicle), N=5 (PTEN iKO 5-azacytidine). (C) N=6 (WT vehicle), N=7 (WT 5-azacytidine), N=4 PTEN iKO vehicle), N=4 (PTEN iKO 5-azacytidine). ANOVA with Bonferroni post hoc. *p<0.05; **p<0.01; ***p<0.001; ****p<0.0001.