Effects of Aminoguanidine on Apoptosis in the Hippocampus and Memory Disorder in a Rat Model of Alzheimer’s Disease

Memory loss is the main disorder accompanied by Alzheimer's disease (AD).

We aimed to investigate the protective effects of aminoguanidine (Amg) on cell apoptosis in the hippocampal CA1 region and memory impairment in male rats received scopolamine (Scop).

Thirty male Wistar rats (200 - 250 g) were randomly divided into the three groups of saline-saline group, Scop + saline, and Scop + Amg groups. The rats received intraperitoneal injection of Scop (3 mg/kg) for seven days, and subsequently, 100 mg/kg of Amg or normal saline were intraperitoneally administrated for 14 consecutive days. The Morris water maze test was used to study memory deficits. Finally, the animals were anesthetized, hippocampi were quickly removed, histological study was performed, and hippocampal cell apoptosis was evaluated by the cresyl violet staining and the terminal deoxynucleotidyl transferase dUTP nick end labeling test, respectively.

Scop injection resulted in reduced pyramidal cells and increased cell apoptosis in the hippocampal CA1 area, and impaired spatial learning and memory. The administration of Amg significantly improved memory and improved the density of pyramidal cells in the hippocampal CA1 area of the rats (P < 0.01). Also, the number of apoptotic cells in the CA1 region of the hippocampus in the Scop + Amg group decreased compared to the Scop + saline group (P < 0.05).

These data demonstrate that the intraperitoneal injection of Amg declined the number of apoptotic cells in the CA1 area of the hippocampus and improved memory impairment in the Scop-induced rat model of AD. It is suggested that Amg may have protective effects against AD.