Horse serum or equine platelet lysate increases total vascular endothelial growth factor A concentrations and correlates with vascular growth in an equine facial arterial ring assay.

This research evaluates the effect of different growth media on the ex vivo growth of blood vessels from equine arterial rings. The study discovered a correlation between concentrations of vascular endothelial growth factor A (VEGF-A) and the growth of vasculature.

Research Methodology

• Facial arteries were collected from 11 horses post-euthanasia, and equine platelet lysate (ePL) was obtained from 6 of these horses.
• Exposed arteries were subjected to different types of growth media: endothelial growth media (EGM) and horse serum (HS); EGM with EDTA; endothelial basal media (EBM); EBM with horse serum; and EBM with human VEGF.
• Additional arterial rings were then treated with various forms and concentrations of equine platelet lysates (ePL), horse serum (HS) and platelet-poor plasma (PPP) combined with either EGM or EBM.
• These different treatments’ effects were closely observed on various vascular growth parameters such as the vascular network area (VNA), branch number, density, and VEGF-A concentration from days 0 to 3.

Research Findings

• Arteries exhibited sprouting when placed in Matrigel supplemented with EBM alone.
• EGM and HS treatment had no significant differences on various parameters like the first sprout (FS), vascular regression (VR), and basement membrane matrix (Matrigel) lysis (ML).
• The VNA in the arteries treated with EGM and HS was found to be significantly greater than in those treated with EBM.
• Maximum network growth (MNG) was markedly higher in arteries exposed to EGM + HS, EBM + HS, and EBM + hVEGF when compared to EBM alone.
• VEGF-A concentrations were found to be higher for EGM with different concentrations of ePL and EGM with HS as compared to EBM, which goes to show a positive correlation between VEGF-A concentration and VNA.

Research Implications and Conclusions

• It was concluded that equine arterial rings can serve as an effective ex vivo model for angiogenesis studies, albeit with a high degree of variability.
• Both horse serum and equine platelet lysate have potential in supporting vascular growth, possibly due to their ability to stimulate the secretion of and act as sources for VEGF-A, a crucial factor in vascular development.