Grapes protect against ultraviolet radiation
Some compounds found in grapes help to protect skin cells from the sun's ultraviolet radiation, according to a study by researchers from the University of Barcelona and the CSIC (Spanish National Research Council). The study supports the use of grapes or grape derivatives in sun protection products.
Ultraviolet (UV) rays emitted by the sun are the leading environmental cause of skin complaints, causing skin cancer, sunburn and solar erythema, as well as premature ageing of the dermis and epidermis. Now, a Spanish study has proven that some substances in grapes can reduce the amount of cell damage caused in skin exposed to this radiation.
UV rays act on the skin by activating 'reactive oxygen species' (ROS). These compounds in turn oxidise macromolecules such as lipids and DNA, stimulating certain reactions and enzymes (JNK and p38MAPK) which cause cell death.
A group of scientists from the University of Barcelona and the CSIC have shown that some polyphenolic substances extracted from grapes (flavonoids) can reduce the formation of ROSs in human epidermis cells that have been exposed to long-wave (UVA) and medium-wave (UVB) ultraviolet radiation. The study, carried out in vitro in the laboratory, has been published in the Journal of Agricultural and Food Chemistry.
The researchers found that the higher the degree of the flavonoids' polymerisation and formation of compounds containing gallic acid, the greater their photoprotective capacity.
The study suggests that these encouraging results should be taken into consideration in clinical pharmacology using plantbased polyphenolic extracts to develop new photoprotection skin products.
Cosmetics and drugs containing grape compounds are already available, but the way they act on cells has not been well understood until now.