Purchase this article with an account.
Steven Roth, John Dreixler, Jacob Mann, Irina Balyasnikova, maciej lesniak; Hypoxic Preconditioned Stem Cells and Rescue of Retinal Ischemia. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):28.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
We have previously shown that delayed injection of bone marrow stem cell conditioned media (BMSC CM), 24 h after ischemia, rescued ischemic retinal functional and histological properties. We hypothesized that preconditioning the BMSC CM by exposure of the BMSCs to hypoxic conditions will increase the efficacy of this protection. In this study we examined the functional and histological outcomes, and the possible mechanisms of this neuroprotection.
Retinal ischemia was produced in adult Wistar rats by increasing IOP for 55 min. BMSCs which were harvested from male Wistar rat femurs were cultured and characterized. The cultured BMSCs produced hypoxic conditioned media, by exposure to hypoxia (1% O2) for 72 h, which was injected into the vitreous 24 h after the end of ischemia. Recovery was assessed one week later using electroretinography (ERG). Scotopic a- and b waves, oscillatory potentials (OPs) and P2 were measured. We also examined 4 micron thick paraffin-embedded sections at 7 d after ischemia. Cytokine protein arrays and mass spectrometry examined the possible factors that are released into hypoxic BMSC CM.
Hypoxic BMSC CM significantly improved recovery of the b-waves and P2 (~82% recovery vs. ~25% recovery for hypoxic unconditioned media; p < 0.001) as well as OP amplitudes, but not the a-waves, after ischemia. Retinal ganglion cell loss after ischemia, as well as the cell density decreases in the inner and outer nuclear layers, was attenuated by the hypoxic BMSC CM. The cytokine protein array found putative protein factors that may play a role in the neuroprotection. TIMP-1, VEGF, β-NGF and CXCL-1 were significantly increased in hypoxic BMSC CM (p < 0.03). Mass spectrometry found unique proteins including collagen α-1 chain, collagen α-2 chain, fibronectin, SPARC, plasminogen activator inhibitor 1, glyceraldehyde-3-phosphate dehydrogenase, peptidyl-prolyl cis-trans isomerase A and actin.
Delayed administration of hypoxic BMSC CM in our rat model of retinal ischemia, resulted in functional and histological neuroprotection. Moreover, analysis of proteins released into the hypoxic BMSC CM found several unique proteins in the hypoxic BMSC CM that may take part in the neuroprotection afforded to the hypoxic conditioned media. The post-ischemic rescue of the retina by a simple intervention using hypoxic preconditioning of autologous stem cells offers exciting possibilities for clinical trials.
This PDF is available to Subscribers Only