Description
Growth differentiation factor 15 (GDF15), also known as MIC-1, PDF, PLAB, and PTGFB, is a member of the transforming growth factor β (TGFβ) superfamily. It plays an important role in regulating inflammatory and apoptotic pathways in injured tissues and during disease processes. This protein is synthesized intracellularly and secreted as a dimer linked by disulfide bonds. GDF15 is widely expressed in adult tissue with most abundant level in the liver, and its expression in liver can be significantly upregulated during injury of organs such as liver, kidney, heart and lung. In the brain, GDF15 expression occurs in the choroid plexus, from which the protein is secreted into the cerebrospinal fluid. As a responsive gene for p53 tumor suppressor protein, the encoded GDF15 protein can prevent cell death by the activation of Akt and inhibition of ERK, and overexpression of GDF15 occurs in certain carcinomas.GDF15 acts as a trophic factor for certain classes of neurons, promoting cell survival and differentiation. Additionally, GDF15 has been identified as a bone marrow-derived factor that abrogates hepcidin-mediated protection from iron overload under conditions of increased erythropoiesis