Prosaposin in the secretome of marrow stroma-derived neural progenitor cells protects neural cells from apoptotic death
Article first published online: 29 DEC 2009
© 2010 The Authors. Journal Compilation © 2010 International Society for Neurochemistry
Journal of Neurochemistry
Volume 112, Issue 6, pages 1527–1538, March 2010
How to Cite
Li, N., Sarojini, H., An, J. and Wang, E. (2010), Prosaposin in the secretome of marrow stroma-derived neural progenitor cells protects neural cells from apoptotic death. Journal of Neurochemistry, 112: 1527–1538. doi: 10.1111/j.1471-4159.2009.06565.x
- Issue published online: 22 FEB 2010
- Article first published online: 29 DEC 2009
- Received August 20, 2009; revised manuscript received December 13, 2009; accepted December 18, 2009.
- marrow stromal cells;
- neural differentiation;
- neural protection;
J. Neurochem. (2010) 112, 1527–1538.
Functionally, adult stem cells not only participate in replication and differentiation to various cell lineages, but also may be involved in rescuing cells from apoptosis. Identifying functional factors secreted by stem cells, as well as their target cells, may advance our understanding of stem cells’ multifaceted physiologic functions. Here, we report that mouse bone marrow stromal cell-derived neuroprogenitor cells (mMSC-NPC) provide a protective function by secreting a key factor, prosaposin (PSAP), capable of rescuing mature neurons from apoptotic death. This factor is identified as the lead protein in the secretome of mMSC-NPC cultures by tandem mass spectroscopic profiling, and further validated by western blotting and immunocytochemistry. The secretome of MSC-NPC reduces toxin-induced cell death in cultures of rat pheochromocytoma neuronal cells, human ReNcell CX neurons, and rat cortical primary neurons; removal of PSAP by immunodepletion annuls this protective effect. This neuronal protection against toxin treatment was validated further by the recombinant PSAP peptide. Interestingly, the secretome of neuronal culture does not possess such a self-protective action. We suggest that upon injury, a subgroup of MSCs differentiates into neural/neuronal progenitor cells, and remains in this intermediate stem cell-like stage, defending injured neighboring mature neurons from apoptosis by secreting PSAP.