The 10th World Congress on Polyphenol Applications in Porto, Portugal, recently heard latest resveratrol research in the area.
Cell membrane targeted
Dr Ana Rute Neves proposed a resveratrol form that exerts its action on the cell membrane’s lipid areas. This action goes on to affect protein activity in the intra-cellular pathways.
“We suggest that resveratrol may interact with cell membranes, thereby influencing the biophysical properties of lipids and consequently modulating trans-membrane proteins, receptors and enzymes involved in cell signalling pathways,” she said.
“Several transmembrane proteins have been identified among the cellular targets of resveratrol. We present data that indicates resveratrol’s ability to be incorporated into lipid membrane models penetrating the hydrophobic core of bi-layers."
The research is of particular importance as biophysical interaction studies of resveratrol are an area that is not well-studied. The majority of research involving the compound tends to focus on its action as an antioxidant, and its ability to reduce oxidative stress.
Interrupted immune response
The University of Burgundy’s Dr Dominique Delmas proposed a novel anti-inflammatory mechanism of action that may provide protection against vascular complications, inflammatory responses and tumour growth.
Delmas and his team revealed data that demonstrated resveratrol’s anti-inflammatory action through a change in microRNA (miRNA) – a small coding molecule that is central to the regulation of gene expression.
In mouse models of melanoma (B16F10), the researchers were able to demonstrate resveratrol’s efficacy in preventing tumour growth and the formation of new blood vessels.
This is achieved via the strong inhibition of Th-17 – a pro-inflammatory protein that along with fellow protein IL-17 has been implicated in tissue inflammation and autoimmune conditions.
“Our results highlight that resveratrol modulates differentiation of lymphocytes Th-17 which exert protumoral activity via IL-17 production,” explained Dr Delmas.
“In addition, CD4 T cells - a subset of cells that form part of the human immune response - displayed less capability to differentiate into Th17 cells in vitro after resveratrol treatment.”
Finally, Dr Virginie Aires, also from the University of Burgundy located in the north east of France, proposed the existence of a multiple signalling pathway that could explain resveratrol’s purported range of health benefits.
Aires’ team homed in on peroxisome proliferator-activated receptors (PPARs) – a specialised group of proteins that help regulate the expression of genes.
PPARs have important roles in the maintenance of cellular differentiation, development, and metabolism (carbohydrate, lipid, protein), as well as tumour formation in humans.
Aire’s study sought to determine whether PPARs were involved in resveratrol-induced cell death. Experiments using colorectal tumour cells demonstrated that when PPARs were activated, tumour cell growth decreased and contributed to resveratrol-induced cell cycle arrest.
Additional experiments showed that rosiglitazone, which targeted the glitazone receptor (PPAR-gamma) PPARG), had efficacy in enhancing a resveratrol-induced cell death.
“Our data shows that PPAR-gamma contributes to resveratrol-induced colon cancer cell death and suggests that the combination of this polyphenol with a PPAR gamma activator could be relevant as a new therapeutic approach to treat digestive cancers.”
Source: Journal of ISANH (International Society of Antioxidants in Nutrition and Health)
Published online ahead of print, DOI:10.18143/JISANH_v3i4
“Resveratrol modulates cell membranes: what’s the story?”
Authors: Ana Rute Neves et al.
“Importance of immune system modulation in anti-inflammatory and antitumoral properties of resveratrol, a polyphenol of wine.”
Authors: Dominique Delmas et al.
“PPARGamma is involved in resveratrol-induced apoptosis and chemosensitization.”
Authors: Virginie Aires et al