Identification of an osteopontin-derived peptide that binds neuropilin-1 and activates vascular cells

Chen, Y.; Gialeli, C.; Shen, J.; Duner, P.; Walse, B.; Duelli, A.; Caing-Carlsson, R.; Blom, A. M.; Zibert, J.; Hultgardh-Nilsson, A.; Alenfall, J.; Liang, C.; Nilsson, J. C.

doi:10.1101/2023.09.05.556237

bioRxiv · 10.1101/2023.09.05.556237

Identification of an osteopontin-derived peptide that binds neuropilin-1 and activates vascular cells

Chen, Y.·Gialeli, C.·Shen, J.·Duner, P.·Walse, B.·Duelli, A.·Caing-Carlsson, R.·Blom, A. M.·Zibert, J.·Hultgardh-Nilsson, A.·Alenfall, J.·Liang, C.·Nilsson, J. C.

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Abstract

BackgroundThe osteopontin-derived peptide FOL-005 has been shown to stimulate hair growth. Using ligand-receptor glycocapture technology we identified neuropilin-1 (NRP-1), a known co-receptor for vascular endothelial growth factor (VEGF) receptors, as the most probable receptor for FOL-005. Considering that induction of perifollicular angiogenesis by VEGF is a critical step in activation of the anagen growth phase of hair follicles, we investigated the effect of the more stable FOL-005 analogue FOL-026 on vascular cells. MethodsX-ray diffraction and microscale thermophoresis analysis were used to determine receptor binding of FOL-peptides. Cultured human arterial smooth muscle cells were used for studies of cell proliferation, migration, intracellular signaling, and apoptosis. A Matrigel plug assay was used to study angiogenesis in vivo. RNA seq. was used to analyze changes in gene expression patterns. ResultsFOL-026 was found to share binding site with VEGF in the NRP-1 b1-subdomain. Stimulation of human umbilical vein endothelial cells with FOL-026 resulted in phosphorylation of AKT and ERK1/2, increased cell growth and migration, stimulation of endothelial tube formation and inhibition of apoptosis in vitro, as well as activation of angiogenesis in vivo. Down-regulation of NRP-1 by NRP-1-specific small interfering RNA blocked the stimulatory effects of FOL-026 on endothelial cells. RNA sequencing showed that FOL-026 activated pathways involved in tissue repair. Exposure of human coronary artery smooth muscle cells to FOL-026 stimulated cell proliferation, migration, inhibited apoptosis, and induced VEGF gene expression by an NRP-1-dependent mechanism. ConclusionsThese findings identify NRP-1 as the receptor for FOL-026 and show that its biological effects mimic that of growth factors binding to the VEGF receptor family. They also suggest that FOL-026 may have therapeutical potential in conditions that require vascular repair and / or enhanced angiogenesis. Clinical perspectiveO_LIInsufficient vascular repair increases the risk of acute cardiovascular events, something that is of particular importance in diabetes. C_LIO_LIA peptide derived from the extracellular matrix protein osteopontin (FOL-026) binds to the vascular endothelial growth factor (VEGF) co-receptor neuropilin-1 stimulating endothelial and vascular smooth muscle cell proliferation and migration as well as the formation of new vessels. C_LIO_LIBy mimicking the effects of VEGF FOL-026 may have therapeutical potential in conditions that require vascular repair and / or enhanced angiogenesis such as vascular complications to diabetes, peripheral artery disease and salvage of ischemic myocardium. C_LI

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Chen, Y., Gialeli, C., Shen, J., Duner, P., Walse, B., Duelli, A., Caing-Carlsson, R., Blom, A. M., Zibert, J., Hultgardh-Nilsson, A., Alenfall, J., Liang, C., Nilsson, J. C.. 2023-09-05. Identification of an osteopontin-derived peptide that binds neuropilin-1 and activates vascular cells. https://doi.org/10.1101/2023.09.05.556237

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