The most dangerous heavy metals are mercury, chromium, lead and nickel, and can have toxic effects on the genetic material of the cells, the researchers explained in a study recently published in the International Journal of Cosmetic Science.
Skin, as the organ most in contact with the external environment, is the most exposed to heavy metal stress and therefore the most damaged by their toxic effects, study author and Scientific Director and Coordinator for Arterra Biosicence, Fabio Apone told CosmeticsDesign-Europe.com.
Inspired by plant’s defence mechanism
Plants are also exposed to heavy metal stress and the defence mechanism of the tomato was the inspiration for the search for a new cosmetic active, explained the researchers.
In response to higher levels of heavy metals in the environment, the levels in the plant cells of metal binding compounds, such as phytochelatins, increase.
“Phytochelatins are unique to plants and are produced in response to metal stress, in order to protect the plants from heavy metal toxicity,” Apone explained.
A skin care product that contains high levels of phytochelatins would help protect skin cells from heavy metal toxicity, he added.
“The phytochelatins contained in the cream bind heavy metals which may come into contact with the skin, thus avoiding that these metals enter the cells and perform their toxic action.”
In vitro tests show protective properties
According to the researchers, the toxicity of heavy metals on cells is largely down to the increase in reactive oxygen species, which led the team to perform a number of in vitro tests to investigate its antioxidant properties.
Cultured fibroblasts were treated with the extract and then stressed with copper (known to elicit reactive oxygen species). According to the study results, fibroblasts treated with the extract had significantly fewer reactive oxygen species than those left untreated.
In addition, the researchers investigated the ability of the extract to protect against DNA damage often associated with oxidative stress. According to the results, cells treated with the tomato cell extract had fewer DNA breakages than those untreated.
Heavy metal stress is also known to stimulate the expression of enzymes that break down collagen and the researchers claim that this upregulation is decreased in the presence of the tomato extract.
In vivo tests in progress
In light of these in vitro results, VitaLab a joint venture between Arterra Bioscience and CRB and the company behind the extract is running in vivo tests. Apone explained that the study will investigate the effect of the extract on skin radiance and lightening.
Source: The International Journal of Cosmetic Science
A tomato stem cell extract, containing antioxidant compounds and metal chelating factors, protects skin cells from heavy metal induced damages
Annalisa Tito, Antonietta Carola, Marida Bimonte, Ani Barbulova, Stefania Arciello, Francesco de Laurentiis, Irene Monoli, Jacqueline Hill, Simone Gibertoni, Gabriella Colucci and Fabio Apone