Isolation of Phenolic Compounds from Raspberry Based on Molecular Imprinting Techniques and Investigation of Their Anti-Alzheimer’s Disease Properties

Abstract

Alzheimer’s disease is the most common neurodegenerative disease, characterized by memory loss and cognitive dysfunction. Raspberry fruits contain polyphenols which have antioxidant and anti-inflammatory properties. In this study, we used molecular imprinting technology to efficiently isolate phenolic components from the raspberry ethyl acetate extracts. Six phenolic components (ellagic acid, tiliroside, kaempferol-3-o-rutoside, gallic acid, ferulic acid and vanillic acid) were identified by UPLC-Q-TOF-MS analysis. Molecular docking was used to predict the anti-inflammatory effects and anti-Alzheimer’s potential of these isolated compounds, which showed a good binding ability to diseases and related proteins. However, the binding energy and docking fraction of ellagic acid, tiliroside, and kaempferol-3-o-rutoside were better than those of gallic acid, ferulic acid and vanillic acid. Additionally, by studying the effects of these six phenolic components on the LPS-induced secretion of inflammatory mediators in murine microglial (BV2) cells, it was further demonstrated that they were all capable of inhibiting the secretion of NO, IL-6, TNF-α, and IL-1β to a certain extent. However, ellagic acid, tiliroside, and kaempferol-3-o-rutoside have better inhibitory effects compared to others. The results obtained suggest that the phenolic components extracted from ethyl acetate extracts of raspberry by molecularly imprinted polymers have the potential to inhibit the progression of Alzheimer’s disease.

Exploring the mechanisms of kaempferol in neuroprotection: Implications for neurological disorders

“…AD is a chronic and progressive neurological disorder characterized by memory loss, loss of functional abilities, and behavioral changes. 78 Individuals with the condition for an extended period typically require a higher level of care. 79 AD is the most prevalent cause of dementia, 80 and future predictions suggest that the greatest growth in dementia prevalence will occur in poor and middle-income nations.…”

“…81 Neuroinflammation, driven by an increase in nitric oxide (NO), interleukin-6 (IL-6), interleukin-1 (IL-1), TNF-α, and other cytotoxic chemicals, is another pathogenic mechanism in AD. 78 A deficiency of cholinergic neurons has also been observed in AD, with cholinergic deficiency linked to the cognitive impairment seen in AD due to the degeneration of cholinergic neurons in the basal forebrain. 82 As of now, there is no effective therapy for AD.…”

“…[83][84][85] Natural products, particularly flavonoids, play a pivotal role in anti-AD therapies. 78 Data from several studies indicate that flavonoids can delay the progression of the disease, thanks to their anti-inflammatory and neuroprotective properties. 84,85 Numerous preclinical investigations have highlighted the neuroprotective properties of kaempferol.…”

“…AD is a chronic and progressive neurological disorder characterized by memory loss, loss of functional abilities, and behavioral changes 78 . Individuals with the condition for an extended period typically require a higher level of care 79 .…”

Anti-Neuroinflammatory Potential of Natural Products in the Treatment of Alzheimer’s Disease

“…At a certain concentration, tiliroside could effectively inhibit the release of pro-inflammatory mediators and the production of ROS in LPS-activated BV2 cells. Additionally, tiliroside could also inhibit the production of PGE2 and the expression of COX-2 [ 194 , 195 ]. It has been reported that tiliroside can improve neuroinflammation in LPS-induced BV2 cells by targeting the Nrf2 pathway and the NF-κB pathway to promote the expression of SIRT1 in microglia and deacetylate NF-κB subunits and, thus, inhibit the transcription of inflammatory genes [ 193 ].…”