Know more

Our use of cookies

Cookies are a set of data stored on a user’s device when the user browses a web site. The data is in a file containing an ID number, the name of the server which deposited it and, in some cases, an expiry date. We use cookies to record information about your visit, language of preference, and other parameters on the site in order to optimise your next visit and make the site even more useful to you.

To improve your experience, we use cookies to store certain browsing information and provide secure navigation, and to collect statistics with a view to improve the site’s features. For a complete list of the cookies we use, download “Ghostery”, a free plug-in for browsers which can detect, and, in some cases, block cookies.

Ghostery is available here for free: https://www.ghostery.com/fr/products/

You can also visit the CNIL web site for instructions on how to configure your browser to manage cookie storage on your device.

In the case of third-party advertising cookies, you can also visit the following site: http://www.youronlinechoices.com/fr/controler-ses-cookies/, offered by digital advertising professionals within the European Digital Advertising Alliance (EDAA). From the site, you can deny or accept the cookies used by advertising professionals who are members.

It is also possible to block certain third-party cookies directly via publishers:

Cookie type

Means of blocking

Analytical and performance cookies

Realytics
Google Analytics
Spoteffects
Optimizely

Targeted advertising cookies

DoubleClick
Mediarithmics

The following types of cookies may be used on our websites:

Mandatory cookies

Functional cookies

Social media and advertising cookies

These cookies are needed to ensure the proper functioning of the site and cannot be disabled. They help ensure a secure connection and the basic availability of our website.

These cookies allow us to analyse site use in order to measure and optimise performance. They allow us to store your sign-in information and display the different components of our website in a more coherent way.

These cookies are used by advertising agencies such as Google and by social media sites such as LinkedIn and Facebook. Among other things, they allow pages to be shared on social media, the posting of comments, and the publication (on our site or elsewhere) of ads that reflect your centres of interest.

Our EZPublish content management system (CMS) uses CAS and PHP session cookies and the New Relic cookie for monitoring purposes (IP, response times).

These cookies are deleted at the end of the browsing session (when you log off or close your browser window)

Our EZPublish content management system (CMS) uses the XiTi cookie to measure traffic. Our service provider is AT Internet. This company stores data (IPs, date and time of access, length of the visit and pages viewed) for six months.

Our EZPublish content management system (CMS) does not use this type of cookie.

For more information about the cookies we use, contact INRA’s Data Protection Officer by email at cil-dpo@inra.fr or by post at:

INRA
24, chemin de Borde Rouge –Auzeville – CS52627
31326 Castanet Tolosan CEDEX - France

Dernière mise à jour : Mai 2018

Menu INRA logo envt small Logo INP-EI Purpan Logo UPS-Tlse3

Home page

Zone de texte éditable et éditée et rééditée

Research

Study and characterization of genotoxic substances; Analysis of genotoxic substances effects, development of genotoxicity bioassays and biotracers

Background

The cells of the digestive tract first, then those of other tissues after systemic passage, may be damaged by genotoxic agents, coming from food contaminants or genotoxins formed in the intestine by commensal flora or by pathogens

Specific lines of research

Cells have to protect their genetic material in order to maintain their activities. Among the DNA damage, induced directly or indirectly, there are changes in the bases (adducts, oxidation,...) and / or DNA breaks (single-strand or double-strand breaks). The double-stranded breaks (DSB) are considered the most toxic form of DNA damage.

A causal link was established between DNA damage, mutagenesis and carcinogenesis. For example:

(i) aflatoxin B1, which forms adducts on guanines, is a known liver carcinogen;

(ii) certain pesticides, probably inducing DNA damage by oxidation of the bases, are carcinogenic;

(iii) recently, Colibactin, a substance produced by bacteria, some commensal E. coli, has been described as a genotoxic agent, probably via the production of DSB, although the mechanism has not been fully characterized.

It is therefore important to control exposure to genotoxic substances, and follow DNA damage that may result from such exposure. For this purpose, we study and characterize genotoxic substances (pesticides, nanoparticules, genotoxins…) through specific assays (comet assays, DSB analysis through well-known biomarkers – γH2AX, 53BP1). We are also interested in analyzing the effects of genotoxic substances, particularly by following the cell destiny (DNA damage and repair analysis, cell cycle checkpoint, cell death, senescence…). Finally, we are highly involved in the development of genotoxicity bioassays as well as the biotracers development, in order to follow the genotoxic effects in living cells and in real time.

Objectives

Our main goal is to develop biotracers and bioessays to detect, track and characterize the DNA damage, directly in living cells. This will help to determine the genotoxicity of substances/contaminants -known or unknown, and help in the prevention and/or diagnosis of exposure to genotoxic to assess the risk of carcinogenesis.

Tools

We propose in particular to develop tools to monitor DSB. The formation of γH2AX foci (histone H2AX phosphorylation) is the most sensitive test to detect DSB, measure the integrity of the genome, and is therefore widely used nowadays. As DSB can be generated directly or indirectly (stop of forks replication in front of lesions) after various genotoxic stresses, the dynamic monitoring of theγH2AX foci formation may help to determine the genotoxic potential of a compound administered to cells in culture. Thus, the γH2AX marker is a tool with a great potential, for many applications from human health to environmental protection. We are working to the development of a γH2AX biotracer to study DSB in real time and in living cells (project supported by an ANR grant). We are also working on bioassays to characterize the genotoxic mechanisms (type of DNA damage, repair mechanisms involved) of the tested substances.

Working areas

In line with the objectives of the UMR 1331 TOXALIM, our research aim to provide answers to the questions being raised about the health effects of exposure to genotoxic as well as tools to characterize these substances .

Our work contributes primarily to the strategic objectives defined by INRA:

· Axis B: improving human nutrition, the health of consumers
· Axis D: develop research and produce the generic data for the knowledge of life.