An 18-year-old man moves from sea level to an elevation of 2,400 m to train as a skier. The increased requirement for oxygen delivery to tissues at the higher elevation stimulates the synthesis of a renal hormone (erythropoietin), which targets hematopoietic stem cells in the bone marrow. Erythropoietin promotes the survival of early erythroid progenitor cells primarily through which of the following mechanisms?
- Recent studies indicate that erythropoietin promotes survival of early erythroid progenitor cells through inhibition of default apoptosis pathway. - Thus, this hormone rescues stem cells that are otherwise fated to undergo programmed cell death. - None of the other choices are known to control the expansion of hematopoietic stem cell colonies in bone marrow.
Altered cell-matrix adhesion
Downregulation of p53
Enhanced glucose uptake
Inhibition of apoptosis
Hematopoeisis: Basic concepts