According to the researchers, from the Technical University of Valencia, the University Hospital La Fe, the University of Valencia, and the Universitat Autonoma de Barcelona, this optimal concentration level is between 120-500 µg/mL.
“Within this range can be found maximum protection against radiation-induced damage and the substance does not reveal either a cytotoxicity nor a genotoxicity effect on nonirradiated human lymphocytes,” said Dr. Alegria Montoro, head of the laboratory of biological dosimetry at the University Hospital La Fe.
The conclusions of this study represent a starting point for future clinical applications using propolis. The results were published February 2012 in the journal Food and Chemical Toxicology, and a full revision of the study will be presented at the annual International Conference of the IEEE Engineering in Medicine and Biology Society EMBC12, which will be held in San Diego (CA, USA), in August 2012.
In the study, the researchers utilized four genetic biomarkers, including the mytotic index and the cell proliferation kinetics, with the aim of determining whether propolis has cytotoxic effects on cells. “Using these biomarkers makes it possible to discover how a substance affects cell division: a substance which is cytotoxic and modifies the cell division stage would do so by accelerating, slowing down or even stopping the process, and all three effects are negative,” explained Dr. Alegria Montoro.
The other two biomarkers used are the study of the possible induction of chromosome changesin nonirradiated cultures at different concentration levels and sister chromatid exchanges (SCEs), a genetic biomarker of exposure to chemical agents.
“With this study we already know the in vitro experimental level, the concentration of propolis to be used to make it act as a radiation protector agent, without being cyto/genotoxic for normal cells. This is the first step, a starting point for future clinical assays. The final goal is to develop capsules containing the adequate doses of propolis, but many more hours of research are needed before we are able to do this,” Dr. Alegria Montoro added.
UAB lecturer Francesc Barquinero, currently on leave to work at the Institut de Radioprotection et de Sûreté Nucléaire (IRSN; Fontenay aux Roses, France), participated in the original planning of the study and its design, as well as the interpretation of the findings and posterior contextualization of other studies published.
In 2008, researchers at the Institute for Industrial, Radiophysical and Environmental Safety (ISIRyM) of the Technical University of Valencia and the University Hospital La Fe demonstrated that propolis can reduce by half the damage inflicted on chromosomes by ionized radiations, thereby protecting the DNA from these effects. The new study is essential, according to the investigators, in finding the range of concentrations in which this compound can have a toxic effect on nonirradiated cells.
Source:
medimaging.net
