Modulation of Beta-Amyloid-Activated Primary Human Neutrophils by Dietary Phenols from Virgin Olive Oil

Abstract

The defense mechanism against harmful stimuli is inflammation. Indeed, neurodegenerative disorders can arise as a result of a persistent neuroinflammation. Beta-amyloid (Aβ1-42) is an early trigger in the origination of Alzheimer’s disease, leading to synaptic and cognitive impairments. Virgin olive oil (VOO) is correlated with a decreased risk of developing immune-inflammatory disorders, but the potential effects of the phenolic fraction (PF) from VOO in the modulation of neuroinflammatory processes in neutrophils remain unknown. In this study, we investigated the ability of the PF to modulate the activation of Aβ1-42-stimulated primary human neutrophils, focusing on the expression of gene and surface markers and the release of pro-inflammatory and chemoattractant mediators. Down-regulation of pro-inflammatory cytokine gene expression in Aβ1-42-treated neutrophils, among other changes, was reported. Furthermore, pretreatment with PF prevented neutrophil activation. The beneficial effects in the modulation of inflammatory responses show the relevance of VOO to achieve a healthier diet that can help prevent inflammatory diseases.

Phenols as an alternative, neuroprotective, and preventive strategy for Alzheimer's disease: (mini-review and bibliometric analysis)

“…Epidemiological studies reviewed have revealed an inversely proportional relationship between the consumption of phenol-rich foods, such as tea, coffee, wine, chocolate, and fruits, and the risk of developing Alzheimer's disease (Pintać et al, 2022;Rivero-Pino et al, 2023). These results support the hypothesis that phenols may prevent or delay the onset of this disease by protecting neurons from oxidative stress and inflammation, two critical pathogenic factors in Alzheimer's disease (Cherbuin et al, 2022;Juiz & Lenarz, 2023).…”

“…There are strategies designed for healthy mental aging (Yamada et al, 2015;Shahidi & Yeo, 2018), highlighting the adoption of healthy habits and incorporation of social, physical and cognitive activities (Makrakis et al, 2022), which, in conjunction with an anti-inflammatory diet high in phenols, can lead to a lower incidence of AD (Tobias et al, 2014;Gao et al, 2019;Bermejo-Pareja et al, 2016;Fernandez et al, 2018.;Azar et al, 2021;Chu et al, 2023). Some phenol-rich foods, such as olive oil, red wine, coffee, tea, cocoa-derived products, a variety of fruits, culinary herbs, and vegetables, have been identified as important sources of polyphenols (Angeloni et al, 2017;Holland et al, 2020;Pintać et al, 2022;Rivero-Pino et al, 2023).…”

Olive Oil Phenolic Compounds’ Activity against Age-Associated Cognitive Decline: Clinical and Experimental Evidence

“…Consequently, this feature has been the subject of many in vitro studies studying the neuroprotective activities of EVOO phenolic compounds (Table 2). Thus, the accumulation of protein aggregates was simulated by treating SH-SY5Y cells [35,42] and neutrophils [40] with Aβ1-42 oligomers to reproduce conditions similar to those encountered in Alzheimer's disease (AD). In SH-SY5Y, HT in synergy with oleuropein, activated the autophagic flux in order to prevent cell damage by Aβ1-42 oligomers, while HT alone (0-20 µM) accelerated the formation of harmless fibrils to the detriment of harmful ones.…”