Protective effects of berry polyphenols against age-related cognitive impairment

Abstract

Abstract.A growing body of evidence suggests that dietary interventions may delay or halt the progression of age-related health disorders and cognitive decline. Among the components of the human diet, polyphenols from berries are essential micronutrients that have been particularly studied for improving cognitive functions. In the present review, we highlight the health impact of major polyphenolic classes found in berries: flavanols, anthocyanins and stilbenes, focusing on resveratrol. The reports of beneficial effects of berry consumption on age-related cognitive decline and associated neurobiological processes in animals and human are underscored. We then discuss the potential benefit of each category of polyphenols on memory impairment and in neurodegenerative diseases. Berry polyphenols improve several types of memory and have a global effect on brain plasticity, partly through their antioxidant activity and/or their effect on neuronal signal transduction and neuroinflammation. Interestingly, accumulated bioavailability data suggest that most polyphenols, or at least key metabolites, can access the brain in sufficient concentrations. Collectively, the data accumulated so far suggest that dietary polyphenols can modulate brain health and function, and strengthen the importance of fruit consumption for a healthy brain aging and the prevention of age-related diseases. However, further preclinical work is needed to determine the most neuroactive nutraceutical formulations, whether through the diet or supplement, to subsequently design and perform informative clinical trials.

Possible neuromodulating role of different grape (Vitis vinifera L.) derived polyphenols against Alzheimer’s dementia: treatment and mechanisms

“…Actually, there is a growing interest in nutritional intervention studies to confirm the neuromodulatory role of polyphenols on brain health and function, as well as to sustain the idea of healthy brain aging (Bensalem et al 2015). At the same time, it is necessary to better define the metabolic profile, absorption profiles, and bioavailability of polyphenols to translate polyphenols-based therapeutic approach in AD animal models into a clinical therapeutic benefit (Mancuso et al, 1822;D' Archivio et al 2010).…”

“…However, further work is needed to better understand polyphenol absorption, metabolism, tissue distribution, intracellular accumulation and excretion, and brain bioavailability. Furthermore, the structural changes and chemical biotransformation of polyphenols during metabolism and interaction with the BBB within the target brain need more clarification to determine their cerebral bioavailability (Bensalem et al 2015). Actually, resolving the bioavailability of natural polyphenols is more challenging than with synthetic compounds (Rubio et al 2014), because resident gut microbiota generates secondary metabolites (Van Duynhoven et al 2011).…”

“…Future studies should focus on administrating bioactive and BBB-permeable polyphenols in either monomeric forms or herbal formulae (Hügel and Jackson 2015). Moreover, further pre-clinical work is needed to determine the most neuroactive nutraceutical formulations, whether through the diet or supplement, to design and perform informative clinical trials (Bensalem et al 2015). Therefore, it is necessary to define the "true bioactive molecules" and the role of metabolism in the pharmacology of ingested polyphenols (Rojo et al 2016).…”

Polyphenols and their benefits: A review

“…[80] A large body of evidence speculates that PCs have protective effects against age-related degenerative diseases. [81] Animal studies and in vitro studies have generally reported the beneficial activities of PCs against HDs, but further explorations are still necessary to determine the accurate mode of action of PCs. The inconsistency between experimental studies and clinical studies may be partly due to the many technical problems with human studies.…”

Identification and Microbial Production of the Raspberry Phenol Salidroside that Is Active against Huntington’s Disease

“…Berries are both an enjoyable and important part of a balanced diet providing energy, nutrients and dietary fiber, and contain a large number of compounds showing diverse health-promoting activities in humans (Seeram, 2012;Nile and Park, 2014). Edible berry species contain a diverse and concentrated portfolio of (poly)phenols such as anthocyanins, flavanols (epicatechin), and stilbenes (resveratrol), which are known to confer protection against oxidative stress and to have cytoprotective activities (Rodriguez-Mateos et al, 2014;Bensalem et al, 2015). In recent years, there is increasing evidence that natural phenols in berry fruits also show protective effects against metabolic disorders such as diabetes and obesity and against neurodegenerative diseases (ND; Yang and Kortesniemi, 2015;Tsuda, 2016;Rosado-Ramos et al, 2018).…”