Biochemical, Histological, and Ultrastructural Studies of the Protective Role of Vitamin E on Cyclophosphamide-Induced Cardiotoxicity in Male Rats.

BACKGROUND: Cyclophosphamide (CP) (Cytoxan or Endoxan) is an efficient anti-tumor agent, widely used for the treatment of various neoplastic diseases. The study aimed to investigate the protective role of vitamin E (vit E) in improving cardiotoxicity in rats induced by CP. MATERIALS AND METHODS: Forty male Wistar rats were divided randomly into four experimental groups (each consisting of ten rats); the control group was treated with saline. The other three groups were treated with vit E, CP, and the combination of vit E and CP. Serum lipid profiles, enzyme cardiac biomarkers, and cardiac tissue antioxidants were evaluated, as well as histological and ultrastructure investigations. RESULTS: CP-treated rats showed a significant increase in serum levels of cardiac markers (troponin, CK, LDH, AST, and ALT), lipid profiles, a reduction in the antioxidant enzyme activities (CAT, SOD, and GPx), and an elevation in the level of lipid peroxidation (LPO). The increase in the levels of troponin, LDH, AST, ALP, and triglycerides is a predominant indicator of cardiac damage due to the toxic effect of CP. The biochemical changes parallel cardiac injuries such as myocardial infarction, myocarditis, and heart failure. Vitamin E played a pivotal role, as it attenuated most of these changes because of its ability to scavenge free radicals and reduce LPO. In addition, vit E was found to improve the histopathological alterations caused by CP where no evidence of damage was observed in the cardiac architecture, and the cardiac fibers had regained their normal structure with minimal hemorrhage. CONCLUSIONS: As a result of its antioxidant activity and its stabilizing impact on the cardiomyocyte membranes, vit E is recommended as a potential candidate in decreasing the damaging effects of CP.

Thymoquinone ameliorates age-related hearing loss in C57BL/6J mice by modulating Sirt1 activity and Bak1 expression.

Age-related hearing loss (AHL) is the most common sensory disorder of aged population. Currently, one of the most important sources of experimental medicine for AHL is medicinal plants. This study performed the first investigation of the effect of thymoquinone (TQ), a potent antioxidant, on AHL. Here, we used inbred C57BL/6J mice (B6 mice) as a successful experimental model of the early onset of AHL. The behavioral assessment of hearing revealed that the injection of a high dose of TQ (40 mg/kg; TQ40) significantly improved the auditory sensitivity of B6 mice at all tested frequencies (8, 16 and 22 kHz). Histological sections of cochlea from B6 mice injected with a low dose (20 mg/kg; TQ20) and high dose showed relatively less degenerative signs in the modiolus, hair cells and spiral ligaments, the main constituents of the cochlea. In addition, TQ40 completely restored the normal pattern of hair cells in B6 mice, as shown in scanning electron micrographs. Our data indicated that TQ20 and TQ40 reduced levels of Bak1-mediated apoptosis in the cochlea of B6 mice. Interestingly, the level of Sirt1, a positive regulator of autophagy, was significantly increased in B6 mice administered TQ40. In conclusion, TQ relieves the symptoms of AHL by downregulating Bak1 and activating Sirt1 in the cochlea of B6 mice.

Sunset Yellow and Allura Red modulate Bcl2 and COX2 expression levels and confer oxidative stress-mediated renal and hepatic toxicity in male rats.

Studies on the adverse health effects caused by azo dyes are insufficient and quite contradictory. This work aims to investigate the possible toxic effect of two types of widely used food additives, Sunset Yellow and Allura Red, by assessing the physiological, histopathological and ultrastructural changes in the liver and kidney. Also, we investigated the genotoxic effect of both dyes on white blood cells. Thirty adult male albino rats were divided into three groups of 10 animals each: control (received water), Sunset Yellow-treated (2.5 mg/kg body weight) and Allura Red-treated (seven mg/kg body weight). The doses were orally applied for 4 weeks. Our results indicated an increase in the biochemical markers of hepatic and renal function (Aspartate aminotransferase, alanine aminotransferase, urea, uric acid and creatinine) in animals administered with the azo dyes. We also observed a noticeable increase in MDA and a marked decrease in total antioxidant levels in azo dye-treated animals compared to controls. Conversely, both dyes adversely affected the liver and kidney of albino rats and altered their histological and fine structure, with downregulation of Bcl2 and upregulation of COX2 expression. Our comet assay results showed a significant elevation in the fold change of tail moment in response to application of Sunset Yellow but not Allura Red. Collectively, we show that Sunset Yellow and Allura Red cause histopathological and physiological aberrations in the liver and kidney of male Wistar albino rats. Moreover, Sunset Yellow but not Allura Red induces a potential genotoxic effect.

Comparative study on the effect of energy drinks on haematopoietic system in Wistar albino rats.

Energy drinks have become popularized and the market value for these drinks is continually growing. Therefore, the present study aimed to evaluate the effect of three popular kinds of energy drinks (Power Horse, Red Bull and Code Red) on certain hematological parameters and on the ultrastructure of blood cells in male Wistar albino rats. Animals were treated orally with Power Horse, Red Bull and Code Red respectively for 4 weeks. Blood samples were taken after two and four weeks for determination of haematological indices. Ultrastructure examination of blood cells was carried only after 4 weeks of treatment. The results indicated significant reduction (P < 0.05) in red blood cell count, haemoglobin content, haematocrit value, blood platelets count and neutrophils in animals treated with Red Bull and Power Horse and these changes were time dependant. Insignificant changes were recorded in rats administered with Code Red. On the other hand, ultrastructural alterations, including both nucleus and cytoplasm of peripheral blood cells, were recorded in all treated animals but they were more pronounced in animals received Red Bull and Power Horse. It is concluded that energy drinks have serious detrimental impacts on haematopoietic system of male rats.