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

OBJECTIVE(S): To investigate the potential therapeutic effect of Bougainvillea spectabilis flower decoction on aluminum chloride (AlCl(3))-induced neurotoxicity. MATERIALS AND METHODS: Rats received daily intraperitoneal injections of AlCl(3) at 10 mg/kg for two months and were treated with B. spectabilis decoction at 50 or 100 mg/kg or saline during the 2(nd) 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, AlCl(3) significantly increased brain MDA and NO along with decreased GSH and PON-1 activity. It also increased AChE, IL-6, and amyloid Aβ concentrations. AlCl(3) 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 AlCl(3) 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 AlCl(3)-treated rats. It also restored memory performance and motor strength, and protected against AlCl(3)-induced neurodegeneration. CONCLUSION: These results suggest that B. spectabilis flower decoction might prove of value in the treatment of Alzheimer’s disease.