Adipocytes express specific lymphangiogenesis membrane receptors

Adipose tissue is a complex, essential, and highly active metabolic and endocrine organ and adipogenesis is influenced by local blood vessel development. Chronic lymphedema, the swelling resulting from deranged lymph transport, leads to progressive tissue alterations like fibrosis and excessive subcutaneous fat. Vascular endothelial growth factors (VEGFs) are crucial regulators of vascular development. In mammals, five different ligands exist and bind to a family of receptor tyrosine kinases. VEGFR‐3 is considered a specific and characteristic receptor in lymphatic endothelial cells (LEC). Increased blood levels of VEGF‐D, the specific ligand for VEGFR‐3 have been demonstrated in lymphedema patients. A possible mechanism for fat hypertrophy observed in lymphedema could be due to undescribed local direct response of adipocytes to VEGF stimulation through VEGFR‐3 receptors in fat cell membrane. Adipocytes were cultured from surgical samples of normal subcutaneous fat and stained with antibodies against VEGFR‐3 using immunohistochemical techniques. VEGFR‐3 was expressed in cultured cells. Even though further studies are needed to ascertain whether stimulation of these receptors play significant role in lymphedema related adipogenesis, these findings shed light upon a possible mechanism for tissue changes in chronic lymph stasis.