A dose-related miRNA panel reveals candidate tissue markers and potential mechanisms for sunset yellow-induced testicular toxicity

Background: Sunset Yellow (SY), a widely used azo dye food additive, has raised increasing health concerns.However, its potential testicular toxicity and the underlying molecular mechanisms, particularly those involv-ing regulatory microRNAs (miRNAs), remain poorly understood. Objective: This study aimed to investigate the effects of SY exposure on testicular histopathology and theexpression patterns of key miRNAs (miR-34c, miR-122, and let-7a) in a rat model. Design: Rats were exposed to low and high doses of SY for 28 days. Testicular tissues were analyzed usingHematoxylin and Eosin (H&E) and quantitative PCR for miRNA expression. Statistical analysis was per-formed to assess dose-dependent effects. Results: SY exposure induced severe histopathological damage in a dose-dependent manner, including dis-rupted seminiferous tubule architecture, germ cell depletion, vacuolization, and interstitial cell changes. High-dose SY caused significant downregulation of miR-34c (P < 0.0001) and upregulation of miR-122 (16.2-fold,P < 0.0001), while let-7a showed alteration only at high doses. The miRNA expression changes showed aparallel association with the severity of histological impairment at the group level. Conclusion: This study demonstrates that SY induces dose-related testicular toxicity via dysregulation of miR-34c and miR-122. These candidate tissue markers are associated with testicular damage and support riskassessment and regulatory strategies, although further mechanistic and validation studies are needed.