Macroalgae Polysaccharides Enhance Brain Health by Mitigating Scopolamine-induced Oxidative Stress and Inflammation Via Nrf-2/TLR4/NF-kB Pathways.

BACKGROUND

Alzheimer's disease (AD) is a neurodegenerative disorder commonly associated with memory loss and difficulties in performing daily activities, particularly in the aging brain.

PURPOSE OF THE STUDY

This study aimed to evaluate the neuroprotective effects of macroalgae-derived polysaccharides from seaweed against scopolamine-induced amnesia, oxidative stress, and amyloid plaque (Aβ) production in rodents, following standard experimental protocols.

METHODS

Three novel polysaccharides were extracted from Chara vulgaris, Cladophora glomerata, and Spirogyra crassa, namely: methylated pectin-type polysaccharides (PS1), methylated pectin-type polysaccharides (homo galacturonan and rhamno galacturonan, PS2), Ulvan-type polysaccharide, and xyloglucan polysaccharides (PS3). These polysaccharides were characterized using a variety of analytical techniques, including SEM, FTIR, XRD, H-NMR, and C-NMR. The polysaccharides were administered at a dose of 30 mg/kg to male albino mice exposed to scopolamine (1 mg/kg) for three weeks. To assess their neuroprotective effects, Morris Water Maze (MWM) and Y-maze tests, antioxidant enzyme assays (Catalase, GSH, LPO), and western blotting were performed.

RESULTS

The results showed that all three polysaccharides significantly (p ≤ 0.001) mitigated redox imbalance and reduced (p ≤ 0.001) microglial activation, thereby decreasing scopolamine-induced neuroinflammation and amyloid beta (Aβ) accumulation. Additionally, these polysaccharides improved neuronal synapses and cognitive function by modulating the NRf-2/TLR4/NF-kB signaling pathway.

DATA ANALYSIS

The data analysis and graph generation were performed using GraphPad Prism software, version 5.0, with a significance level set at a p-value of < 0.05.

CONCLUSION

The findings highlighted the potential of these three novel natural polysaccharides as promising candidates for the treatment of scopolamine-induced oxidative stress-mediated neurodegenerative disorders, such as Alzheimer's disease.