title: Use of an adult rat retinal explant model for screening of potential retinal ganglion cell neuroprotective therapies.
abstract: PURPOSE. To validate an established adult organotypic retinal explant culture system for use as an efficient medium-throughput screening tool to investigate novel retinal ganglion cell (RGC) neuroprotective therapies. METHODS. Optimal culture conditions for detecting RGC neuroprotection in rat retinal explants were identified. Retinal explants were treated with various recognized, or purported, neuroprotective agents and cultured for either 4 or 7 days ex vivo. The number of cells surviving in the RGC layer (RGCL) was quantified using histologic and immunohistochemical techniques, and statistical analyses were applied to detect neuroprotective effects. RESULTS. The ability to replicate previously reported in vivo RGC neuroprotection in retinal explants was verified by demonstrating that caspase inhibition, brain-derived neurotrophic factor treatment, and stem cell transplantation all reduced RGCL cell loss in this model. Further screening of potential neuroprotective pharmacologic agents demonstrated that betaxolol, losartan, tafluprost, and simvastatin all alleviated RGCL cell loss in retinal explants, supporting previous reports. However, treatment with brimonidine did not protect RGCL neurons from death in retinal explant cultures. Explants cultured for 4 days ex vivo proved most sensitive for detecting neuroprotection. CONCLUSIONS. The current adult rat retinal explant culture model offers advantages over other models for screening potential neuroprotective drugs, including maintenance of neurons in situ, control of environmental conditions, and dissociation from other factors such as intraocular pressure. Verification that neuroprotection by previously identified RGC-protective therapies could be replicated in adult retinal explant cultures suggests that this model could be used for efficient medium-throughput screening of novel neuroprotective therapies for retinal neurodegenerative disease.
authors.affiliation: Cambridge Centre for Brain Repair, University of Cambridge, United Kingdom.
authors.forename: Natalie D
authors.initials: ND
authors.lastname: Bull
authors.forename: Thomas V
authors.initials: TV
authors.lastname: Johnson
authors.forename: Guncha
authors.initials: G
authors.lastname: Welsapar
authors.forename: Nicholas W
authors.initials: NW
authors.lastname: DeKorver
authors.forename: Stanislav I
authors.initials: SI
authors.lastname: Tomarev
authors.forename: Keith R
authors.initials: KR
authors.lastname: Martin
mesh_terms: D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D019208:Brain-Derived Neurotrophic Factor / Q000494:pharmacology; D061945:Caspase Inhibitors; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D018920:Coculture Techniques; D005576:Colforsin / Q000494:pharmacology; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology; D009409:Nerve Crush; D018696:Neuroprotective Agents / Q000494:pharmacology*; D009798:Ocular Hypertension / Q000517:prevention & control*; D009900:Optic Nerve; D009901:Optic Nerve Diseases / Q000517:prevention & control*; D009924:Organ Culture Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D012165:Retinal Ganglion Cells / Q000166:cytology* / Q000502:physiology; D033581:Stem Cell Transplantation
chemical_list: D000590:Amino Acid Chloromethyl Ketones; D019208:Brain-Derived Neurotrophic Factor; D061945:Caspase Inhibitors; D018696:Neuroprotective Agents; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; D005576:Colforsin