Inhibition of aluminum chloride-induced amyloid Aβ peptide accumulation and brain neurodegeneration by Bougainvillea spectabilis flower decoction

Iran J Basic Med Sci. 2021 Oct;24(10):1437-1445. doi: 10.22038/IJBMS.2021.58246.12940.

Abstract

Objectives: To investigate the potential therapeutic effect of Bougainvillea spectabilis flower decoction on aluminum chloride (AlCl3)-induced neurotoxicity.

Materials and methods: Rats received daily intraperitoneal injections of AlCl3 at 10 mg/kg for two months and were treated with B. spectabilis decoction at 50 or 100 mg/kg or saline during the 2nd month of the study. The control group received saline. Brain malondialdehyde (MDA), nitric oxide (NO), reduced glutathione (GSH), acetylcholinesterase (AChE), amyloid Aβ peptide, and interleukin-6 (IL-6) concentrations and paraoxonase-1 (PON-1) activity were determined and brain histology was done. Behavioral and neurological testing included Morris water maze (WMZ), Y maze, and wire hanging.

Results: Compared with saline controls, AlCl3 significantly increased brain MDA and NO along with decreased GSH and PON-1 activity. It also increased AChE, IL-6, and amyloid Aβ concentrations. AlCl3 impaired motor strength and memory performance and caused brain neurodegeneration. B. spectabilis decoction given at 50 or 100 mg/kg protected against the biochemical and histopathological alterations evoked by AlCl3 by alleviating the increase in MDA and NO, and decrease in GSH and PON-1 activity. B. spectabilis decoction showed no significant effect on AChE but markedly decreased IL-6 and amyloid Aβ in the brain of AlCl3-treated rats. It also restored memory performance and motor strength, and protected against AlCl3-induced neurodegeneration.

Conclusion: These results suggest that B. spectabilis flower decoction might prove of value in the treatment of Alzheimer's disease.

Keywords: Aluminum chloride; Amyloid Aβ; Bougainvillea spectabilis- flowers; Interleukin-6; Neurodegeneration; Oxidative stress; Paraoxonase.