Food dyes use is still controversial as many of them have been related to health problems, mostly in children. Sunset Yellow is among the food colourings that have been linked to various health risks in animal models. Curcumin has been shown to possess potent anti-inflammatory, anti-tumoural and anti-oxidative properties. To study the possible ultrastructural and molecular changes induced due to 6 weeks oral administration of Sunset Yellow with or without curcumin on the testes and livers of young Sprague-Dawley (S.D.) rats, 36 male animals were randomly assigned into 6 groups: group (1): control (fed a standard diet without any additive); group (2): curcumin control (15 mg/kg b. wt.); group (3): Sunset Yellow I (157.5 mg/kg b. wt.); group (4): Sunset Yellow I with curcumin; group (5): Sunset Yellow II (315 mg/kg b. wt.) and group (6): Sunset Yellow II with curcumin. The ultrastructural investigations revealed that Sunset Yellow induced remarkable pathological changes comprising the whole testis, most frequent of which were vacuolization and/or accumulation of lipid droplets, as well as deposition of electron-dense material in the cell cytoplasm and cellular degeneration. At the same time, the liver showed ultrastructural cyto- and histopathological abnormalities such as nuclear atypia, accumulated lipid droplets, vacuolated cytoplasm, dilated rough endoplasmic reticulum (rER) and congested sinusoids with blood cells. Increasing dietary Sunset Yellow concentration led to the development of various signs of damage in both testis and liver tissues. The mRNA expression, by semi-quantitative RT-PCR analysis, revealed that genes related to testicular-functions (testis-specific transporter; TST1), apoptosis (bcl-2, caspase-3) and cellular detoxification (glutathione peroxidase; GPx), were significantly altered in the testis and liver specimens isolated from the Sunset Yellow-treated groups. Co-administration of curcumin moderately reversed the Sunset Yellow effects on the ultrastructural level, except for the livers obtained from rats exposed to high Sunset Yellow concentration, and mostly alleviated the studied gene expression close to the control levels. It seems that dietary uptake of Sunset Yellow resulted in pronounced deleterious effects on the testes and livers of S.D. rats, while curcumin prompted a protective role, by antagonizing the apoptotic action and enhancing the peroxidase antioxidant activity process. This supports the necessity of re-evaluating and reconsidering the usage of Sunset Yellow as a food colouring agent.
Sunset Yellow, rat, testis, liver, gene expression, ultrastructure