The Effect of Both Vitamin E and Thymoquinone on Monoamine Neurotransmitter Changes Induced by Nicotine Treatment and Withdrawal in The Cortex and Hippocampus of Rat Brain

Both vitamin E and thymoquinone have been used in the treatment of many neurodegenerative disorders. This study aims to investigate the effect of vitamin E or thymoquinone on the alterations in monoamine neurotransmitters induced by nicotine treatment and withdrawal in adult male albino rats. Animals were divided into control group (0.9% NaCl saline solution), nicotine-treated group (1mg/kg B.W.), nicotine (1mg/kg B.W) + vitamin E (75 mg/kg B.W.) treated group and nicotine (1mg/kg B.W) + thymoquinone (5 mg/kg B.W.) treated group. Animals were sacrificed after 14 and 28 days of daily treatment and after 3 and 7 days of stopping the treatments that persisted for 28 days. The brain was dissected to obtain the cerebral cortex and hippocampus and the levels of dopamine, norepinephrine and serotonin were determined by spectrofluorimeter. The results obtained have shown that the combined treatment of nicotine with vitamin E or thymoquinone alleviated the changes in monoamine neurotransmitters induced by nicotine during the treatment and withdrawal periods. The prominent effects of vitamin E or thymoquinone were observed during nicotine withdrawal. This was evident from the restoration of almost all the neurochemical changes induced in the hippocampus and cortex in the monoamine neurotransmitters to nearly control-like values. Thus it could be suggested that the administration of either vitamin E or thymoquinone during smoking could reduce the neurochemical changes induced by nicotine and the withdrawal symptoms induced by nicotine cessation.