The University of Georgia College of Veterinary Medicine

eorgia Veterinary Scholars Program

GVSP Summer 2008 Scholars

Georgia Veterinary Scholar	Faculty Mentor

Marissa Wolfe University of Georgia Class of 2011	Dr. Clifton Baile

Targeting Apelin Signaling: An Approach Towards Decreasing Adiposity

Wolfe, A. Marissa*. Rayalam, Srujana; Hartzell, Diane L; Baile, Clifton A.; Department of Veterinary Medicine, Department of Animal & Dairy Science & Foods & Nutrition, University of Georgia, Athens, GA 30602

Apelin is a peptide growth factor that binds the APJ receptor with high affinity. Apelin signaling is believed to be involved in pathological angiogenesis in solid tumors. However, the effect of apelin on inducing angiogenesis in adipose tissue has not been investigated. Adipogenesis & angiogenesis occuring together
indicates that intervention of obesity might be achieved by targeting vasculature. Thus, targeting adipose tissue vasculature by blocking apelin signaling with anti-apelin antibodies will lead not only to inhibition of
angiogenesis in adipose tissue but also to decreased adiposity. Apelin was reported to stimulate endothelial cell proliferation & angiogenesis to a similar potency as vascular endothelial growth factor (VEGF). In spite of
APJ receptors on adipocytes, apelin did not stimulate adipocyte proliferation indicating that apelin might stimulate endothelial cell specific proliferation leading to increase in adiposity. In this study the angiogenic effect of apelin in adipose tissue explants was investigated. Visceral adipose tissue was obtained from C57/BL6 mice & an in vitro adipose tissue angiogenesis assay was performed. The adipose tissue explants were treated with various concentrations of apelin, VEGF & heparin hydrocortisone complex (negative control) for two weeks & the extent of angiogenesis was noted. The results showed no significant effect of apelin or VEGF on blood vessel development but a decreased angiogenesis was seen with negative control. Further studies are needed to optimize the experimental conditions & will include inhibiting apelin-induced
angiogenesis using anti-apelin antibodies.

Research Support: Seed Grant From CAES UGA & GRA Endowment Fund held by CAB
Student Support: T35 R35 RR022685