ACS67, a hydrogen sulphide-releasing derivative of latanoprost acid, attenuates retinal ischemia and oxidative stress to RGC-5 cells in culture.
Neville N. Osborne 1*,
Dan Ji 2,
Aman Majid 2,
Rebecca Fawcett 2,
Anna Sparatore 3,
and
Piero Soldato 4
1 Nuffield Lab of Ophthalmology, University of Oxford, Walton Street, Oxford, OX2 6AW, United Kingdom
2 Ophthalmology, Oxford University, Oxford, United Kingdom
3 Dept. Science & Parmaceut., Pietro Pratesi, Milan, Italy
4 CTG Pharma, Milan, Italy
* To whom correspondence should be addressed. E-mail: neville.osborne{at}eye.ox.ac.uk.
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Abstract |
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Purpose. To determine the neuroprotective properties of a latanoprost acid derivative (ACS67) that donates the gas hydrogen sulphide (H2S).
Methods. Ischemia to the rat retina was induced by elevation of intraocular pressure. Electroretinograms (ERGs) were recorded and retinas analysed by immunohistochemistry, Western blotting and RT-PCR two days later. Hydrogen peroxide (H2O2) was used to give an insult to RGC-5 cells in culture. The nature of the insult to cultures was quantified by the resazurin-reduction assay procedure, staining for reactive oxygen species (ROS) and for apoptosis. ACS67, its sulfurated moiety (ACS1) and latanoprost were tested both for their toxicity and ability to blunt the negative effect of H2O2 to RGC-5 cells. In addition, an assay was used to see whether any of the substances influenced glutathione (GSH) levels in RGC-5 cells.
Results. Partial damage to the retina in situ after ischemia was characterised by an alteration of the ERG, a reduction in the retinal localisation of specific antigens and a reduction and elevation of defined retinal proteins and mRNAs. Optic nerve axonal proteins were also drastically reduced by ischemia. Most of these changes were significantly blunted by an intravitreal injection of ACS67 directly after ischemia. ACS67 and ACS1 and the antioxidant epigallocatechin gallate (EGCG) all stimulated GSH levels and significantly attenuated H2O2-induced toxicity to RGC-5 cells while this was not the case for latanoprost.
Conclusion. We conclude that ACS67 acts as a H2S donor through its donating moiety ACS1 and as a consequence is able to act as a neuroprotectant.
Key Words:
retinal ischemia, antioxidants, cell culture, apoptosis
