EFFECT OF SODIUM FLUORIDE ON THE GREY MATTER OF SPINAL CORD IN THE ALBINO RAT AND THE PROTECTIVE ROLE OF GREEN TEA EXTRACT

Abstract

Objectives: Fluoride is a toxic and reactive element. Human beings are exposed to fluoride from various sources such as toothpastes, mouth rinses, dietary supplements and ordinary drinking water. This work investigated the effect of sodium fluoride (NaF), alone or with green tea, on the grey matter of spinal cord of adult male albino rats.
Methods: Spinal cord sections were examined using light and electron microscopy. Immunohistochemical assessments for the expression of caspase-3 and glial fibrillary acidic protein were performed. Agarose gel electrophoresis was used for DNA fragmentation.
Results: Our results showed that NaF produced neurodegeneration, vacuolation and haemorrhage with some abnormal blood vessels and a significant increase in the number and size of astrocytes. In addition, the neurons showed a significant decrease of their Nissl’s granules content and significant increased expression of caspase-3.
Conclusion: Green tea exerted a protective effect against NaF-induced neurotoxicity. The results of this work add to the known toxic effects of NaF and provide a new insight into the possible use of green tea to ameliorate these effects.

Keywords

• fluoride
• gel electrophoresis
• green tea
• histopathology
• immunohistochemistry
• spinal cord

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