GC/MS and LC-ESI-MS Analysis of Conocarpus erectus Leaves Extract via Regulating Amyloid-β-Peptide, Tau Protein, Neurotransmitters, Inflammation and Oxidative Stress against AlCl 3 -Induced Alzheimer's Disease in Rats

This study investigated the therapeutic effect of Conocarpus erectus leaves methanolic extract against AlCl -induced Alzheimer's disease (AD) in rats comparing with Donepezil-hydrochloride as a reference drug. The bioactive compounds of C. erectus leaves were isolated and identified by GC/MS and LC-ESI-MS analysis. Malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), amyloid-β-peptide (Aβ-peptide), tau protein, acetylcholinesterase (AChE), serotonin (5-HT), dopamine (DA) and nor-adrenaline (NE) levels were estimated. The neuromuscular strength, memory behavior and histopathological examination of cerebral cortex region were also conducted. Forty-three compounds were characterized from the non-polar fraction of C. erectus L. leaves extract and nineteen compounds were identified from the defatted extract. AlCl - induction caused significant elevation of brain oxidative stress, Aβ-peptide, tau protein, IL-6, TNF-α and AChE levels. A significant decrease in 5-HT, ND and DA levels were noticed. Additionally, AlCl reduced neuromuscular strength and compromised memory function. Treatment of AlCl3- induced rats with C. erectuse extract ameliorated these selected parameters by variable degrees. In conclusion, C. erectus protects against AlCl - induced AD in rats through its antioxidant, anti-inflammatory, and antineural damage. [Correction added on 3 December 2024, after first online publication: The term "antineutron" was corrected to "antineural" in the preceding sentence.]. It could be considered as a new nutraceutical agent for attenuating symptoms associated with Alzheimer's disease.