Roles of erythropoietin in human milk

Erythropoietin (Epo) is one of many biologically active growth factors present in human and animal milk. Accumulating evidence shows important developmental roles for these milk-borne growth factors. Although Epo is present in biologically relevant amounts in mammalian milk, the roles of Epo in milk are incompletely defined. A significant proportion of milk-borne Epo resists proteolytic degradation. Epo receptors (EpoR) have been found on gastric mucosa and intestinal mucosa, and in mesenteric vessel endothelium. Evidence to date shows that intact Epo reaches these local organs, as well as distal organs. After feeding Epo, local gastrointestinal physiological effects are seen in suckling rats. In humans and rats, short-term feeding of high-dose Epo increases reticulocytes, but it is unclear whether sustained treatment increases red cell mass.

Further work towards understanding the physiological and potential pharmacological roles of enterally administered Epo is necessary.