The current study investigates the anti-amnesic effect of taurine using scopolamine induced dementia rat model. Rats were divided into control, dementia rat model induced by daily treatment with scopolamine for 14 days and rats co-treated daily with taurine and scopolamine for 14 days. At the end of the experiment, dementia was evaluated behaviorally by novel object recognition test (NORT). The neurochemical changes induced in the cortex and hippocampus were assessed by measuring norepinephrine (NE), dopamine (DA), serotonin (5-HT), monoamine oxidase (MAO), acetylcholinesterase (AChE), Na+,K+,ATPase, oxidative stress parameters including malondialdehyde (MDA), nitric oxide (NO), and reduced glutathione (GSH), interleukin-1α (IL-1α), and interleukin-6 (IL-6).

In NORT data showed impaired memory in rats treated with scopolamine as indicated by the significantly decreased recognition index (RI) and the negative value of the discrimination ratio (DR). A significant increase in DA, MDA, NO, AChE, MAO, IL-1α, and IL-6 and a significant decrease in NE, GSH, and Na+,K+,ATPase were recorded in the cortex and hippocampus of rat model of dementia. Protection with taurine prevented the dementia as indicated by the control-like value of RI and the positive value of DR. This was mediated by the protective effect of taurine against the changes in DA, NE, MAO, AChE and Na+,K+,ATPase induced by scopolamine in the selected brain regions. In addition, taurine showed ameliorative effect against the oxidative stress and the neuroinflammation induced in the cortex and hippocampus by scopolamine.

It is clear from the present behavioral and neurochemical findings that taurine has anti-amnesic effect against scopolamine induced dementia in rats. This effect could be attributed to the antioxidant and anti-inflammatory effects of taurine. In addition, the ability of taurine to prevent the cortical and hippocampal changes in NE and DA induced by scopolamine has a substantial role in its anti-amnesic effect.