Summary
DENAQ, an azobenzene-based photoswitch, can restore light sensitivity to retinal ganglion cells in degenerated canine retinas at relatively low light intensities (0.2 mW/cm²), offering a potential pharmacological approach to vision restoration. However, aqueous solubility limitations causing focal drug aggregates and ocular toxicity suggest that next-generation photoswitches with improved formulations will be necessary for clinical translation.
Key Findings
- DENAQ at 1 mM (ex vivo) or 3–10 mM (in vivo injection, 150 µL) restored light responses in RGCs of degenerated canine retinas at light intensities as low as 0.2 mW/cm² using 455 nm light.
- Both number of light-sensitive cells and per-cell response amplitude increased with light intensity up to the maximum tested intensity of 85 mW/cm².
- Application to retinas with partially preserved cone function caused DENAQ-driven responses to appear in both cone-driven and previously non-responsive RGCs, while simultaneously suppressing existing cone-driven responses.
- Repeated stimulation slowed activation and accelerated recovery of DENAQ-driven responses, likely causing delayed responses to 4 Hz flicker stimulation.
- Experiments conducted on 9 degenerated and 6 wild-type canine retinas; limited aqueous solubility led to focal drug aggregates associated with ocular toxicity, limiting DENAQ's direct therapeutic potential.
Categories
Eye Health & Vision: Investigates photochemical restoration of light sensitivity in degenerated retinas using azobenzene-based photoswitches, directly relevant to vision restoration in photoreceptor degeneration.
The Science of Light: Examines photoreceptor biology and light-dependent ionic channel control via photopharmacological compounds, with specific spectral (455 nm) and intensity parameters quantified.
Author(s)
S Nikonov, N Dolgova, R Sudharsan, I Tochitsky
Publication Year
2022
Number of Citations
1
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