The influence of sleep deprivation on expression of apoptosisregulatory proteins p53, bcl‑2 and bax following rat tonguecarcinogenesis induced by 4‑nitroquinoline 1‑oxide

Abstract

Background: The aim of this study was to evaluate whether paradoxical sleep deprivation couldaffects the mechanisms and pathways essentials for cancer cells in tongue cancer induced by4‑nitroquinole 1‑oxide in Wistar rats.

Materials and Methods: For this purpose, the animals were distributed into 4 groups of 5 animalseach treated with 50 ppm 4 nitroquinoline 1 oxide (4 NQO) solution through their drinkingwater for 4 and 12 weeks. The animals were submitted to paradoxical sleep deprivation (PSD)for 72 h using the modified multiple platform method, which consisted of placing 5 mice in acage (41 × 34 × 16 cm) containing 10 circular platforms (3.5 cm in diameter) with water 1 cmbelow the upper surface. The investigations were conducted using immunohistochemistry of p53,Bax and Bcl‑2 proteins related to apoptosis and its pathways. Statistical analysis was performedby Kruskal‑Wallis non‑parametric test followed by the Dunn’s test using SPSS software pack(version 1.0). P value < 0.05 was considered for statistic significance.

Results: Although no histopathological abnormalities were induced in the epithelium after 4 weeksof carcinogen exposure in all groups, in 12 weeks were observed pre‑neoplasic lesions. Data analysisrevealed statistically significant differences (P < 0.05) in 4 weeks group for p53 and for bcl‑2 andfor all immunomarkers after 12 weeks of 4NQO administration.

Conclusion: Our results reveal that sleep deprivation exerted alterations in proteins associatedwith proliferation and apoptosis in carcinogenesis.

Key Words:Apoptosis, carcinogenesis, rat, sleep deprivation