Protective effects of zingerone on the retina in diabetic rats

AIM: To investigate the effects of zingerone (ZO) on the retina in diabetic rats. • METHODS: A total of 70 rats were randomly selected and divided into seven groups [diabetic group (Dm+; n=10), diabetic+metformin group (Dm+Met; n=10), diabetic+ZO25 group (Dm+ZO25; n =10), diabetic+ZO50 group (Dm+ZO50; n =10), diabetic+metformin group+ZO 50 Group (Dm+Met+ZO50; n=10)]. Diabetes was induced by streptozotocin (STZ), and metformin and two different doses of ZO were administered via gavage. Retinal tissues were evaluated by histopathological and immunohistochemical analyses. • RESULTS: In diabetic rats, severe retinal inflammation, tissue necrosis, and increased tumor necrosis factor-α (TNF-α) expression were observed. ZO administration reduced these effects in a dose-dependent manner. Protective effects of metformin alone were limited, and no synergistic benefit was observed in ZO+Met groups. Administration of 50 mg/kg ZO to non-diabetic rats caused no retinal toxicity. Additionally, elevated 8-OHdG and c-Jun N-terminal kinase (JNK) expressions in diabetic retinopathy models were significantly reduced by ZO treatment. • CONCLUSION: ZO can markedly reduce the pathological effects of the retina in a diabetic rat model.