Research Paper Volume 13, Issue 6 pp 7781—7799

Twist1 signaling in age-dependent decline in angiogenesis and lung regeneration

Endothelial Twist1 mediates age-dependent inhibition of post-PNX compensatory lung growth. (A) Graphs showing the ratio of the weight of right lung cardiac lobe to mouse BW in the 2M vs. 24M old Twist1fl/fl or Twist1fl/fl/Tie2-cre mice after PNX (n=6, mean ± s.e.m., *, pB) H&E-stained mouse lungs in the cardiac lobe of 2M vs. 24M old Twist1fl/fl or Twist1fl/fl/Tie2-cre mice after PNX (top, 3rd) Scale bar, 25 μm. IF micrographs showing staining of CD31, VEGFR2 and DAPI in 2M vs. 24M old Twist1fl/fl or Twist1fl/fl/Tie2-cre mice after PNX (2nd, bottom). Scale bar, 100 μm. (C) Graph showing integrated density of VEGFR2 in 2M vs. 24M old Twist1fl/fl or Twist1fl/fl/Tie2-cre mice after PNX (n=5-6, mean ± s.e.m., *, pD) Graph showing the mRNA levels of Vegfr2 in the ECs isolated from 2M vs. 24M old Twist1fl/fl or Twist1fl/fl/Tie2-cre mouse lungs after PNX (n=5, mean ± s.e.m., *, p

Figure 5. Endothelial Twist1 mediates age-dependent inhibition of post-PNX compensatory lung growth. (A) Graphs showing the ratio of the weight of right lung cardiac lobe to mouse BW in the 2M vs. 24M old Twist1fl/fl or Twist1fl/fl/Tie2-cre mice after PNX (n=6, mean ± s.e.m., *, p<0.05). (B) H&E-stained mouse lungs in the cardiac lobe of 2M vs. 24M old Twist1fl/fl or Twist1fl/fl/Tie2-cre mice after PNX (top, 3rd) Scale bar, 25 μm. IF micrographs showing staining of CD31, VEGFR2 and DAPI in 2M vs. 24M old Twist1fl/fl or Twist1fl/fl/Tie2-cre mice after PNX (2nd, bottom). Scale bar, 100 μm. (C) Graph showing integrated density of VEGFR2 in 2M vs. 24M old Twist1fl/fl or Twist1fl/fl/Tie2-cre mice after PNX (n=5-6, mean ± s.e.m., *, p<0.05). (D) Graph showing the mRNA levels of Vegfr2 in the ECs isolated from 2M vs. 24M old Twist1fl/fl or Twist1fl/fl/Tie2-cre mouse lungs after PNX (n=5, mean ± s.e.m., *, p<0.05).