Insulin-like growth factor-binding protein-like 1 (IGFBPL1)

Insulin-like growth factor-binding protein-like 1 (IGFBPL1) is a secreted protein and a member of the IGFBP family that serves as a critical modulator of insulin-like growth factor 1 (IGF-1) bioactivity (UniProt Q8WX77). It functions by binding to IGF-1 and facilitating its interaction with the IGF-1 receptor (IGF-1R), which triggers essential downstream signaling cascades, including the PI3K/mTOR and calcium pathways (Guo et al., 2018). In the central nervous system, IGFBPL1 is vital for the growth and regeneration of retinal ganglion cell axons and acts as a master regulator of microglial homeostasis, shifting microglia from a pro-inflammatory to a pro-homeostatic state to resolve neuroinflammation (Li et al., 2023). These properties make it a promising therapeutic target for neurodegenerative diseases such as glaucoma, Alzheimer's disease, and tauopathies (FireCyte Therapeutics). Beyond its neurological roles, IGFBPL1 acts as a putative tumor suppressor, often silenced by hypermethylation in various cancers, and plays a protective role in cardiovascular health by inhibiting macrophage lipid accumulation (Aging-US, 2021). Therapeutic strategies currently under development involve the administration of recombinant IGFBPL1 to halt disease progression and promote tissue repair.

Other names

IGFBP-related protein 10Insulin-like growth factor-binding-related protein 4IGFBP-rP4IGFBPRP4bA113O24.1

Enhancement of IGF-1R signaling through direct binding to IGF-1, activation of mTOR and calcium signaling pathways, and modulation of SORT1 and DCC receptors.