Therapeutic potential of taurine in a pigmented rat model of age-related macular degeneration.

<h4>Purpose</h4>To investigate the potential protective effects of taurine supplementation against retinal degeneration in an animal model of mild dry age-related macular degeneration (AMD).<h4>Methods</h4>To test the effects of a taurine supplement in mild dry AMD, sodium iodate (NaIO₃)-induced retinal degeneration model was used. Two administration methods, intraperitoneal (IP) and intravenous (IV), were used to deliver NaIO₃ in pigmented Long Evans rats to generate mild and severe dry AMD, respectively. Structural abnormalities were evaluated <i>in vivo</i> using near-infrared (IR) reflectance fundus imaging and optical coherence tomography (OCT). Using the slow progressive mild AMD model, we investigated the neuroprotective effects of oral taurine supplementation (1.5% w/v in drinking water) against NaIO₃-induced retinal degeneration over 20 weeks. In addition, a human Retinal Pigment Epithelium (RPE, hTERT-RPE1) cell culture model was used to directly assess taurine's ability to protect against NaIO₃-related oxidative stress.<h4>Results</h4>The high-dose IV model (80 mg/kg) exhibited extensive and severe retinal damage, with ONL thinning by 64.2% and total retinal thickness (TRT) by 47.6%, predominantly in the peripapillary region. In contrast, the lower-dose IP model (50 mg/kg) displayed milder, more gradual deterioration (outer nuclear layer (ONL) thinning by 19.4% and TRT by 11.5%). Oral taurine supplementation significantly preserved ONL and TRT <i>in vivo</i> and supported RPE-1 cell survival, proliferation, and motility, under NaIO₃ conditions.<h4>Conclusion</h4>Taurine supplementation provided significant structural protection against NaIO₃-induced damage both <i>in vivo</i> and in cell culture, demonstrating its potential as a therapeutic candidate for mitigating mild dry AMD progression.