Qiju Granule alleviates retinal damage in a mouse model of age-related macular degeneration.

BACKGROUND: Age-related macular degeneration (AMD) is the leading cause of visual loss in older people. Despite recent advances, the pathophysiology of AMD remains incompletely understood, and current therapies are limited. Qiju Granule is a traditional herbal formulation with therapeutic potential; however, its efficacy and mechanisms in AMD remain unclear. OBJECTIVE: The aim of this study was to evaluate the protective effects of Qiju Granule in a mouse model of AMD and investigate potential underlying mechanisms. METHODS: AMD-like retinal injury was induced in C57BL/6J mice by chronic light exposure combined with hydroquinone feeding. Retinal function and structure were assessed using electroretinography and histomorphological analyses. Retinal cell apoptosis and the expression of key angiogenic factors (VEGF and CD31) were assessed to explore underlying mechanisms. RESULTS: Qiju Granule treatment significantly preserved retinal function, as reflected by improved electroretinographic responses, and maintained structural integrity of the retina and RPE layer. Mechanistically, Qiju Granule exerted potent anti-apoptotic effects, evidenced by a marked reduction in TUNEL-positive retinal cells. Furthermore, it downregulated VEGF and CD31 expression, indicating suppression of aberrant angiogenic signaling. CONCLUSION: Our findings identified a protective role of Qiju Granule in mitigating AMD-related retinal damage and suggested its potential as a therapeutic candidate to prevent progression to advanced AMD.