Research Paper Volume 13, Issue 6 pp 7781—7799

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

Twist1-PGC1α signaling mediates age-dependent decline in vascular formation in the subcutaneously implanted gel. (A) IF micrographs of fibrin gel supplemented with GFP-labeled young (50 years old) human adipose ECs treated with lentivirus overexpressing PGC1α or Twist1 shRNA and subcutaneously implanted on NSG mice for 7 days. As a control, young vs. aged human adipose ECs were treated with lentivirus encoding control shRNA with irrelevant sequences or vector alone. Scale bar, 100 μm. Graph showing vascular area in the gel (n=7, mean ± s.e.m., *, pB) IF micrographs of fibrin gel supplemented with GFP-labeled aged human adipose ECs treated with lentivirus encoding Twist1 shRNA or in combination with PGC1α shRNA or VEGFR2 inhibitor (SU5416) and subcutaneously implanted on NSG mice for 7 days. As a control, aged human adipose ECs were treated with lentivirus encoding control shRNA with irrelevant sequences or control vehicle. Scale bar, 100 μm. Graph showing vascular area in the gel (n=7, mean ± s.e.m., *, p

Figure 4. Twist1-PGC1α signaling mediates age-dependent decline in vascular formation in the subcutaneously implanted gel. (A) IF micrographs of fibrin gel supplemented with GFP-labeled young (<50 years old) vs. aged (>50 years old) human adipose ECs treated with lentivirus overexpressing PGC1α or Twist1 shRNA and subcutaneously implanted on NSG mice for 7 days. As a control, young vs. aged human adipose ECs were treated with lentivirus encoding control shRNA with irrelevant sequences or vector alone. Scale bar, 100 μm. Graph showing vascular area in the gel (n=7, mean ± s.e.m., *, p<0.05). (B) IF micrographs of fibrin gel supplemented with GFP-labeled aged human adipose ECs treated with lentivirus encoding Twist1 shRNA or in combination with PGC1α shRNA or VEGFR2 inhibitor (SU5416) and subcutaneously implanted on NSG mice for 7 days. As a control, aged human adipose ECs were treated with lentivirus encoding control shRNA with irrelevant sequences or control vehicle. Scale bar, 100 μm. Graph showing vascular area in the gel (n=7, mean ± s.e.m., *, p<0.05).