The effect of grape seed procyanidins extract on cognitive function in elderly people with mild cognitive impairment: A randomized, double-blind, placebo-controlled clinical trial

Effectiveness of Grape-Based Interventions on Cognitive and Mental Health: Evidence From Human Trials

PURPOSE OF REVIEW

This review evaluates current research on grape-based interventions and their impact on cognitive and mental health. It also explores the putative mechanisms by which the grape-derived compounds might modulate cognitive function. The growing prevalence of cognitive decline and mental health disorders necessitates exploring novel dietary approaches. Grapes, rich in polyphenols, have demonstrated potential benefits in preclinical studies. However, translating these findings to humans remains an ongoing endeavor.

RECENT FINDINGS

Recent clinical trials complement existing observational data, suggesting a positive influence of grape consumption on cognition, particularly in areas of memory, learning, and overall cognitive function and emotional well-being. The potential mechanisms involve the antioxidant and anti-inflammatory properties of grapes, which may mitigate neuroinflammation and protect brain cells from free radical damage. Evidence from existing research suggests that grape based interventions may improve cognitive performance through several neuroprotective mechanisms; however, further investigation is needed to understand the protective effects of grape-based interventions on brain function and mental health. Large-scale trials to assess the long-term effects and safety profile of grape interventions are required. Additionally, extensive epidemiological research is needed to confirm the effect of grape interventions on cognitive health and to determine the best beneficial dosage and duration of supplementations to maximise cognitive benefits.

In Vitro Mechanistic Studies of a Standardized Sustainable Grape Seed Extract for Potential Application as a Mood-Modulating and Cognition-Enhancing Supplement

BACKGROUND

Grape seed extract (GSE) from Vitis vinifera L. is rich in polyphenols and oligomeric proanthocyanidin complexes (OPCs), and it has shown potential benefits in managing low mood and cognitive function. In this study, we investigated the potential bioactivities of Enovita®, a standardized GSE extract (GSEe herein) rich in OPCs, in key mechanistic pathways related to low mood conditions and cognitive function.

METHODS

In vitro assays were conducted to assess GSEe's inhibitory effects on γ-aminobutyric acid transaminase (GABA-T) and monoamine oxidase A (MAO-A), its binding affinity to the GABA site of GABA-A receptors, and its effects on acetylcholinesterase (AChE). Its neuroprotective effects on human SH-SY5Y neuroblastoma cells under oxidative stress (induced by H2O2) were assessed using MTT and LDH release assays. Its antioxidant activities were evaluated using DPPH, ABTS, FRAP, ORAC, HORAC, total phenolic content, and TAS assays. Its cytotoxicity was also evaluated.

RESULTS

GSEe showed significant GABA-T inhibitory activity. It also exhibited MAO-A and AChE inhibition, along with moderate binding affinity to the GABA-A receptor. In neuroprotective assays, GSEe provided significant protection to SH-SY5Y cells against oxidative stress. GSEe demonstrated robust antioxidant activity in all assays, including scavenging of DPPH and ABTS radicals, high ferric-reducing power, high polyphenolic contents, and a substantial total antioxidant capacity.

CONCLUSIONS

GSEe exhibits promising bioactivities, highlighting its potential as a supplement for modulating mood and enhancing cognitive function. Overall, the promising results from these in vitro studies provide a strong foundation for the continued exploration and development of GSEe as a viable natural supplement for enhancing mental health and cognitive function.

Ultrasonic-assisted extraction of grape seed procyanidins, preparation of liposomes, and evaluation of their antioxidant capacity

The residue remaining after oil extraction from grape seed contain abundant procyanidins. An ultrasonic-assisted enzyme method was performed to achieve a high extraction efficiency of procyanidins when the optimal extraction conditions were 8 U/g of cellulase, ultrasound power of 200 W, ultrasonic temperature of 50 ℃, and ultrasonic reaction time of 40 min. The effects of free procyanidins on both radical scavenging activity and thermal stability at 40, 60, and 80 ℃ of the procyanidins-loaded liposomal systems prepared by the ultrasonic-assisted method were discussed. The presence of procyanidins at concentrations ranging from 0.02 to 0.10 mg/mL was observed to be effective at inhibiting lipid oxidation by 15.15 % to 69.70 % in a linoleic acid model system during reaction for 168 h, as measured using the ferric thiocyanate method. The procyanidins-loaded liposomal systems prepared by the ultrasonic-assisted method were characterized by measuring the mean particle size and encapsulation efficiency. Moreover, the holographic plots showed that the effect-response points of procyanidins combined with α-tocopherol in liposomes were lower than the addition line and 95 % confidence interval limits. At the same time, there were significant differences between the theoretical IC50add value and the experimental IC50mix value. The interaction index (γ) of all combinations was observed to be less than 1. These results indicated that there was a synergistic antioxidant effect between procyanidins combined with α-tocopherol, which will show promising prospects in practical applications. In addition, particle size differentiation and morphology agglomeration were observed at different time points of antioxidant activity determination (0, 48, 96 h).