Objective: The current study aimed to explore the harmful impact of oral administration of sunset yellow on the circumvallate papillae of albino rats.
Design:16 male albino rats weighing 150-200g were classified into two groups (8 animals in each group). Group I control group. Group II was treated with 5 mg/kg body weight sunset yellow. All the animals were sacrificed after 4 weeks from the beginning of the experiment by ketamine overdose. The circumvallate papillae of the two groups were examined histologically, immunohistochemically for detecting apoptosis by using PCNA, histomorphometrically to detect the number of PCNA-positive cells and by real-time polymerase chain reaction for measuring the expression level of NF-κB. All the results were statistically analyzed.
Results: Treatment with sunset yellow disrupted the structural integrity of the circumvallate papillae resulting in dysplasia, increased apoptotic cells, shortened and completely obliterated trough as a result of hyperplasia of the epithelial lining of the trough, atrophy and degeneration of taste buds. There was a significant decrease in PCNA-positive cells denoting apoptosis and abnormal proliferation. Moreover, a significant increase in NF-κB expression was observed denoting inflammation.
Conclusion: The oral administration of sunset yellow showed destructive, neoplastic, and even carcinogenic effects on the circumvallate papillae.
Keywords: Sunset Yellow, Rats, PCNA, NF-κB, Circumvallate papillae.