METHODS: Three groups of Sprague Dawley rats were used: intervention, vehicle group and negative control groups (n = 6 in each). Intravenous injection of 60 mg/kg sodium iodate (day 0) induced retinal degeneration. On day 4 post-injection of sodium iodate, the rats in the intervention group received intravenous DPSC and subretinal DPSC in the right eye; rats in the vehicle group received subretinal Hank's balance salt solution and intravenous normal saline; while negative control group received nothing. Electroretinogram (ERG) was performed to assess the retinal function at day 0 (baseline), day 4, day 11, day 18, day 26, and day 32. By the end of the study at day 32, the rats were euthanized, and both their enucleated eyes were sent for histology.
RESULTS: No significant difference in maximal ERG a-wave (p = 0.107) and b-wave, (p = 0.153) amplitude was seen amongst the experimental groups. However, photopic 30 Hz flicker amplitude of the study eye showed significant differences in the 3 groups (p = 0.032). Within the intervention group, there was an improvement in 30 Hz flicker ERG response of all 6 treated right eyes, which was injected with subretinal DPSC; while the 30 Hz flicker ERG of the non-treated left eyes remained flat. Histology showed improved outer nuclear layer thickness in intervention group; however, findings were not significant compared to the negative and vehicle groups.
CONCLUSION: Combination of subretinal and intravenous injection of DPSCs may have potential to rescue cone function from a NaIO3-induced retinal injury model.
Methods: Sprague-Dawley (SD) rats were divided into three groups: a no-treatment control group (n = 6), balanced salt solution (BSS) treatment group (n = 6), and hUC-MSCs treatment group (n = 6). Visual functions were assessed by flash visual evoked potential (fVEP) at baseline, Week 3, and Week 6 after optic nerve crush injury. Right eyes were enucleated after 6 weeks for histology.
Results: The fVEP showed shortened latency delay and increased amplitude in the hUC-MSCs treated group compared with control and BSS groups. Higher cellular density was detected in the hUC-MSC treated group compared with the BSS and control groups. Co-localized expression of STEM 121 and anti-S100B antibody was observed in areas of higher nuclear density, both in the central and peripheral regions.
Conclusion: Peribulbar transplantation of hUC-MSCs demonstrated cellular integration that can potentially preserve the optic nerve function with a significant shorter latency delay in fVEP and higher nuclear density on histology, and immunohistochemical studies observed cell migration particularly to the peripheral regions of the optic nerve.