Pleiotrophin promotes capillary-like sprouting from senescent aortic rings

Area of Science:

• Cardiovascular Biology
• Regenerative Medicine
• Aging Research

Background:

• Pleiotrophin (PTN) is a growth factor crucial for angiogenesis, impacting development and tumor growth.
• PTN therapy promotes neovascularization after myocardial infarction.
• Angiogenesis is impaired during aging, necessitating research into restorative therapies.

Purpose of the Study:

• To investigate if Pleiotrophin (PTN) growth factor therapy can restore neovascularization in aged tissues.
• To evaluate the effects of PTN on capillary-like endothelial sprouting in senescent rats.

Main Methods:

• Ex vivo culture of thoracic aortic rings from adult and senescent rats (3 and 24 months old).
• Cultured aortic rings in a 3D collagen matrix with varying concentrations of recombinant human PTN or Vascular Endothelial Growth Factor-165 (VEGF).
• Quantified capillary network length using image analysis at day 3 and 6.

Main Results:

• Capillary-like tube formation was reduced in aged (24 mo) aortic rings compared to younger ones (3 mo).
• PTN significantly increased capillary-like tube formation in a dose-dependent manner in both age groups.
• PTN treatment successfully restored age-associated impaired angiogenesis in senescent aortic segments, comparable to VEGF effects.

Conclusions:

• Pleiotrophin (PTN) effectively induces ex vivo angiogenesis in aged tissues.
• PTN shows promise as a novel therapy for neovascularization in aged individuals.
• Potential applications include treating age-associated ischemia in cardiac, hindlimb, and cerebral tissues.