A fully-detailed LC-MS qualitative profiling of red grape skin, extracted with a mixture of ethanol and water (70:30 v:v) has permitted the identification of 65 compounds which can be classified into the following chemical classes: organic and phenolic acids (14 compounds), stilbenoids (1 compound), flavanols (21 compounds), flavonols (15 compounds) and anthocyanins (14 compounds). The extraction yield obtained with water at different temperatures (100 °C, 70 °C, room temperature) was then evaluated and the overall polyphenol content indicates that EtOH:H₂O solvent is the most efficient and selective for polyphenol extraction. However, by analyzing the recovery yield of each single polyphenol, we found that water extraction under heating conditions is effective (extraction yield similar or even better in respect to the binary solvent) for some polyphenolic classes, such as hydrophilic procyanidins, phenolic acids, flavonol glucosides and stilbenoids. However, according to their lipophilic character, a poor yield was found for the most lipophilic components, such as flavonol aglycones, and in general for anthocyanins. The radical scavenging activity was in accordance with the polyphenol content, and hence, much higher for the extract obtained with the binary solvent in respect to water extraction. All the tested extracts were found to have an anti-inflammatory activity in the R3/1 cell line with NF-kb reporter challenged with 0.01 µg/mL of IL-1α, in a 1 to 250 µg/mL concentration range. An intriguing result was that the EtOH:H₂O extract was found to be superimposable with that obtained using water at 100 °C despite the lower polyphenol content. Taken together, the results show the bioactive potentialities of grape skin extracts and the possibility to exploit this rich industrial waste. Water extraction carried out by heating is an easy, low-cost and environmentally friendly extraction method for some polyphenol classes and may have great potential for extracts with anti-inflammatory activities.

Background: Cellular senescence is a biological process with a dual role in organismal health. While transient senescence supports tissue repair and acts as a tumor-suppressive mechanism, the chronic accumulation of senescent cells contributes to aging and the progression of age-related diseases. Senotherapeutics, including senolytics, which selectively eliminate senescent cells, and senomorphics, which modulate the senescence-associated secretory phenotype (SASP), have emerged as promising strategies for managing age-related pathologies. Among these, polyphenols, a diverse group of plant-derived bioactive compounds, have gained attention for their potential to modulate cellular senescence. Methods: This review synthesizes evidence from in vitro, in vivo, and clinical studies on the senolytic and senomorphic activities of bioactive polyphenols, including resveratrol, kaempferol, apigenin, and fisetin. The analysis focuses on their molecular mechanisms of action and their impact on fundamental aging-related pathways. Results: Polyphenols exhibit therapeutic versatility by activating SIRT1, inhibiting NF-κB, and modulating autophagy. These compounds demonstrate a dual role, promoting the survival of healthy cells while inducing apoptosis in senescent cells. Preclinical evidence indicates their capacity to reduce SASP-associated inflammation, restore tissue homeostasis, and attenuate cellular senescence in various models of aging. Conclusions: Polyphenols represent a promising class of senotherapeutics for mitigating age-related diseases and promoting healthy lifespan extension. Further research should focus on clinical validation and the long-term effects of these compounds, paving the way for their development as therapeutic agents in geriatric medicine.

A “green” solvent-free industrial process (patent pending) is here described for a grape seed extract (GSE) preparation (Ecovitis™) obtained from selected seeds of Veneto region wineries, in the northeast of Italy, by water and selective tangential flow filtration at different porosity. Since a comprehensive, non-ambiguous characterization of GSE is still a difficult task, we resorted to using an integrated combination of gel permeation chromatography (GPC) and electrospray ionization high resolution mass spectrometry (ESI-HRMS). By calibration of retention time and spectroscopic quantification of catechin as chromophore, we succeeded in quantifying GPC polymers up to traces at n = 30. The MS analysis carried out by the ESI-HRMS method by direct-infusion allows the detection of more than 70 species, at different polymerization and galloylation, up to n = 13. This sensitivity took advantage of the nanoscale shotgun approach, although paying the limit of missed separation of stereoisomers. GPC and MS approaches were remarkably well cross-validated by overlapping results. This simple integrated analytical approach has been used for quality control of the production of Ecovitis™. The emerging feature of Ecovitis™ vs. a popular benchmark in the market, produced by a different technology, is the much lower content of species at low n and the corresponding increase of species at high n.

Enocianina is an anthocyanin-rich extract obtained from grape pomace. It is widely used as a colorant in the food industry and, in addition to anthocyanins, it also contains a variety of polyphenols. To understand whether enocianina, besides its coloring effect, may offer potential health benefit applications, we aimed to fully characterize the profile of four commercial enocianinas and assess their radical scavenging, enzymatic, antioxidant, and anti-inflammatory activities. LC-ESI-MS/MS analysis identified 90 phytochemicals. The relative content of each anthocyanin was assessed by a semi-quantitative analysis, with malvidin derivatives being the most abundant. UV-VIS spectroscopy detected total amounts of polyphenols and anthocyanins of 23% and 3.24%, respectively, indicating that anthocyanins represent a minor fraction of total polyphenols. Multiple linear regression analysis indicated that the radical scavenging activity is related to the total polyphenol content and not to anthocyanins. All four enocianinas dose-dependently activate Nrf2, and such activity was correlated with catechol-containing polyphenol content. Finally, all enocianinas showed dose-dependent anti-inflammatory activity, which at the highest concentrations tested was closely related to the total polyphenol content and was explained by radical scavenging, Nrf2 activation, and other mechanisms related to the polyphenolic components.

Background/Objectives: 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone (γ-VL), recently identified as a predominant microbial metabolite derived from proanthocyanidins, offers benefits such as reducing inflammation, oxidative stress, and supporting brain health. Its effects on neuroinflammation and microglial activation remain largely unexplored. Curcumin, a bioactive component isolated from Curcuma longa L., is well known for its ability to reduce microglial activation and pro-inflammatory mediator production and release. While the individual effects of γ-VL and curcumin are well documented, their potential combined effects remain unexplored. This research sought to investigate the possible synergistic effects of γ-VL and curcumin in reducing microglial activation. Methods: Primary rat cortical microglia were pre-treated with γ-VL and curcumin, alone or in combination, before stimulation with LPS. An MTT assay was used to evaluate cell viability, while pro-inflammatory mediators were assessed by real-time PCR and ELISA. Nitric oxide production was evaluated with the Griess assay. SynergyFinder Plus software analyzed potential synergistic effects. Results: The combination of low micromolar concentrations of γ-VL and curcumin synergistically reduced LPS-induced microglial activation. Specifically, the combination exhibited a significantly greater ability to inhibit the production and release of pro-inflammatory factors (such as IL-1β, TNF-α, and NO) compared to each compound individually. Mechanistically, the anti-inflammatory activity was attributed to the downregulation of NLRP3 expression, and the reduction in microglial activation was linked to the modulation of the NOX2/Nrf2 signaling pathway. Conclusions: The combination of low micromolar concentrations of γ-VL and curcumin produces synergistic anti-inflammatory effects in microglia by targeting key inflammatory pathways, indicating its potential utility as a treatment strategy for neurodegenerative diseases involving microglial activation.

Background: The sustainable use of agro-industrial by-products is essential to reduce environmental impact and enhance resource efficiency. In this study, white grape skins (WGSs), a distillation by-product of grappa production, are valorized through the development of an eco-friendly extraction process. Methods: At the laboratory scale, water-based and hydroalcoholic extractions are evaluated, prioritizing the water-based method due to its better scalability and eco-sustainability. Furthermore, this green extraction method enables industrial scale-up by Distillerie Bonollo Umberto S.p.A. (Mestrino, Italy), resulting in Vituva^®, an industrial extract with a composition comparable to its water-based laboratory counterpart. LC-HRMS-based targeted metabolomics identified 50 metabolites in the hydroalcoholic extract, 36 in the water-based extract, and 37 in the industrial extract, which included mainly polyphenols such as flavonoids and phenolic acids. Results: In vitro assays show that the water-based and industrial extracts exhibit significant anti-inflammatory activity, especially in gastric epithelial cells, while the hydroalcoholic extract displays stronger antioxidant activity via Nrf2 pathway activation but was more cytotoxic, possibly due to polyphenol-induced hormesis. Notably, the industrial extract also activates Nrf2 to a lesser extent, supporting its dual bioactivity profile. Chemoinformatic and statistical analyses support the identification of the likely mechanisms of action. Conclusions: Overall, this work demonstrates how green chemistry and circular economy principles transform a waste product into a high-value bioactive ingredient.