Background: Oxidative stress and chronic inflammation, at both the systemic and the central level, are critical early events in atherosclerosis and Alzheimer’s disease (AD). Purpose: To investigate the oxidative stress-, inflammation-, and Tau-phosphorylation-lowering effects of pomegranate polyphenols (PPs) (punicalagin, ellagic acid, peel, and aril extracts). Methods: We used flow cytometry to quantify the protein expression of proinflammatory cytokines (IL-1β) and anti-inflammatory mediators (IL-10) in THP-1 macrophages, as well as M1/M2 cell-specific marker (CD86 and CD163) expression in human microglia HMC3 cells. The IL-10 protein expression was also quantified in U373-MG human astrocytes. The effect of PPs on human amyloid beta 1-42 (Aβ_1-42)-induced oxidative stress was assessed in the microglia by measuring ROS generation and lipid peroxidation, using 2′,7′-dichlorofluorescein diacetate (DCFH-DA) and thiobarbituric acid reactive substance (TBARS) tests, respectively. Neuronal viability and cell apoptotic response to Aβ_1-42 toxicity were assayed using the MTT (3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide) assay and the annexin-V-FITC apoptosis detection kit, respectively. Finally, flow cytometry analysis was also performed to evaluate the ability of PPs to modulate Aβ_1-42-induced Tau-181 phosphorylation (pTau-181). Results: Our data indicate that PPs are significantly (p < 0.05) effective in countering Aβ_1-42-induced inflammation through increasing the anti-inflammatory cytokines (IL-10) in U373-MG astrocytes and THP1 macrophages and decreasing proinflammatory marker (IL-1β) expression in THP1 macrophages. The PPs were also significantly (p < 0.05) effective in inducing the phenotypic transition of THP-1 macrophages and microglial cells from M1 to M2 by decreasing CD86 and increasing CD163 surface receptor expression. Moreover, our treatments have a significant (p < 0.05) beneficial impact on oxidative stress, illustrated in the reduction in TBARS and ROS generation. Our treatments have significant (p < 0.05) cell viability improvement capacities and anti-apoptotic effects on human H4 neurons. Furthermore, our results suggest that Aβ_1-42 significantly (p < 0.05) increases pTau-181. This effect is significantly (p < 0.05) attenuated by arils, peels, and punicalagin and drastically reduced by the ellagic acid treatment. Conclusion: Overall, our results attribute to PPs anti-inflammatory, antioxidant, anti-apoptotic, and anti-Tau-pathology potential. Future studies should aim to extend our knowledge of the potential role of PPs in Aβ_1-42-induced neurodegeneration, particularly concerning its association with the tauopathy involved in AD.

Modern research achievements support the health-promoting effects of natural products and diets rich in polyphenols. Pomegranate (PG) (Punica granatum L.) contains a considerable number of bioactive compounds that exert a broad spectrum of beneficial biological activities, including antimicrobial, antidiabetic, antiobesity, and atheroprotective properties. In this context, the reviewed literature shows that PG intake might reduce insulin resistance, cytokine levels, redox gene expression, blood pressure elevation, vascular injuries, and lipoprotein oxidative modifications. The lipid parameter corrective capabilities of PG-ellagitannins have also been extensively reported to be significantly effective in reducing hyperlipidemia (TC, LDL-C, VLDL-C, and TAGs), while increasing plasma HDL-C concentrations and improving the TC/HDL-C and LDL-C/HDL-C ratios. The health benefits of pomegranate consumption seem to be acheived through the amelioration of adipose tissue endocrine function, fatty acid utilization, GLUT receptor expression, paraoxonase activity enhancement, and the modulation of PPAR and NF-κB. While the results from animal experiments are promising, human findings published in this field are inconsistent and are still limited in several aspects. The present review aims to discuss and provide a critical analysis of PG’s bioeffects on the components of metabolic syndrome, type-2 diabetes, obesity, and dyslipidemia, as well as on certain cardiovascular-related diseases. Additionally, a brief overview of the pharmacokinetic properties, safety, and bioavailability of PG-ellagitannins is included.

Atherosclerosis is a chronic inflammatory cardiovascular disease that may result from the interaction between oxidative stress, immune dysregulation, and metabolic disorders. Recent studies indicate that the well-known phenolic compounds, hydroxytyrosol (HTyr) and tyrosol (Tyr) present in extra virgin olive oil, confer cardioprotection through various mechanisms of action that include antioxidant, anti-inflammatory, and metabolic regulatory properties. The gut microbiota modulates the structure, bioavailability, and bioactivity of these phenolic compounds, thereby influencing their therapeutic potential. This review explores the intricate interactions between Tyr, HTyr, and gut microbiota within the context of atherosclerosis prevention and management. We explore how gut microbial metabolism can magnify or alter the biological effects of the Tyr and HTyr, and how interindividual differences in microbiota composition may influence their efficacy. A deeper understanding of these mechanisms could support the development of precision nutrition strategies aimed at reducing the risk of atherosclerosis.

Modern research achievements support health-promoting effects of natural products and diets rich in polyphenols. Pomegranate (PG) (Punica granatum L.) contain a considerable number of bioactive compounds that exert a broad spectrum of beneficial biological activities, including antimicrobial, antidiabetic, antiobesity, and atheroprotective properties. In this view, the reviewed literature shows that PG intake might reduce insulin resistance, cytokine levels, redox gene expression, blood pressure elevation, vascular injuries and lipoprotein oxidative modifications. Lipid parameters corrective capabilities of PG-ellagitannins are also sufficiently reported to be significantly effective in reducing hyperlipidemia (TC, LDL-C, VLDL-C, and TAGs), plasma HDL-C concentrations, TC/HDL-C and LDL-C/HDL-C ratio. The health benevolent effects of pomegranate consumption appear to be produced through the amelioration of adipose tissue endocrine function, fatty acid utilization, GLUT receptor expression, paraoxonase activity enhancement, PPAR and NFκB modulation. Although the results from animal experiments are encouraging, human findings published in this field are inconsistent and still limited in many points of view. The present review discusses and provides a critical analysis of PG's bioeffects on metabolic syndrome components, type-2 diabetes, obesity, and dyslipidemia, as well as on some cardiovascular-related diseases. A brief overview of the pharmacokinetic properties, safety, and bioavailability of PG-ellagitannins is also included.

Oxidative stress and chronic inflammation, both at the systemic and central level, are critical early events in atherosclerosis and Alzheimer’s disease (AD). Purpose. To investigate the oxidative stress, inflammatory, and Tau-phosphorylation lowering effects of pomegranate polyphenols (PP) (punicalagin, ellagic acid, peels, and arils extracts). Methods. We used flow cytometry to quantify protein expression of proinflammatory cytokines (IL-1β) and anti-inflammatory mediators (IL-10) in THP-1 macrophages, as well as M1/M2 cell-specific markers (CD86 and CD163) expression in human microglia HMC3 cells. IL-10 protein expression was also quantified in U373-MG human astrocytes. The effect of PP on human amyloid beta 1-42 (Aβ1-42)-induced oxidative stress was assessed in microglia by measuring ROS generation and lipid peroxidation, using respectively two ′,7′-dichlorofluorescein diacetate (DCFH-DA) and thiobarbituric acid reactive substances (TBARS) tests. Neuronal viability and cell apoptotic response to Aβ1-42 toxicity were assayed using the MTT (3-(4, 5-dimethyl thiazolyl-2)-2, 5-diphenyltetrazolium bromide) assay and the annexinV-FITC apoptosis detection kit; respectively. Finally, flow cytometry analysis was also performed to evaluate the ability of PP to modulate Aβ1-42-induced Tau-181 phosphorylation (pTau-181). Results. Our data indicate that PP was significantly (p<0.05) effective in countering Aβ1-42-induced inflammation through increasing the anti-inflammatory cytokines (IL-10) (in U373-MG astrocytes and THP1 macrophages) and decreasing proinflammatory markers (IL-1β) expression in THP1 macrophages. PP was also significantly (p<0.05) effective in inducing the phenotypic transition of THP-1 macrophages and microglial cells from M1 to M2 by decreasing CD86 and increasing CD163 surface receptor expression. Moreover, our treatments have a significant (p<0.05) beneficial impact on oxidative stress, illustrated in the reduction of TBARS and ROS generation. Our treatments have significant (p<0.05) cell viability improvement capacities and anti-apoptotic effects on human H4 neurons. Furthermore, our results suggest that Aβ1-42 significantly (p<0.05) increases pTau-181. This effect was significantly (p<0.05) attenuated by arils, peels, and punicalagin and drastically reduced by ellagic acid treatments. Conclusion. Our results are attributed to PP's anti-inflammatory, antioxidant, anti-apoptotic, and anti-Tau pathology potential. Future studies should aim to extend our knowledge of the potential role of PP on A1-42-induced neurodegeneration, mainly its association with the tauopathy involved in AD.

Extra virgin olive oil (EVOO) polyphenols are recognized for their beneficial effects on human health, yet how their concentration shapes biological outcomes remains insufficiently explored. While a daily intake of 25 mL EVOO is generally regarded as beneficial for cardiovascular protection, the high-phenolic EVOO examined in this study contains markedly higher levels of polyphenols than most EVOOs reported previously. This suggests that oils richer in polyphenols may exert distinct biological effects. To investigate this, we compared extracts from a standard EVOO and a naturally high-phenolic EVOO, along with their key phenolic compounds, hydroxytyrosol (HT) and tyrosol (Tyr). Antioxidant effects were assessed by quantifying intracellular reactive oxygen species (ROS) and lipid peroxidation. Anti-inflammatory activity was evaluated in THP-1-derived macrophages stimulated with LPS by analyzing inflammatory surface markers’ expression, cytokines’ production, and the NLRP3-inflammasome pathway. Atheroprotective potential was investigated by measuring cholesterol efflux in J774 macrophages. Both EVOO polyphenols extracts and (HT and Tyr) significantly reduced ROS and lipid peroxidation. High phenolic EVOO extract (EVOOPE+) displayed superior antioxidant activity at lower concentrations, while standard EVOO phenolic extract (EVOOPE) showed more consistent effects across doses. Both extracts favored an anti-inflammatory macrophage phenotype, as indicated by increased CD163 and IL-10 expression and reduced CD86, IFN-α, and NLRP3. Moreover, all treatments enhanced cholesterol efflux in a dose-dependent manner, with EVOOPE+ and HT producing the strongest effects. Collectively, these results highlight the capacity of EVOO polyphenols to modulate, through key bioactivity mechanisms, cardioprotective effects and emphasize the importance of polyphenols concentration in their biological efficacy.