Know more

About cookies

What is a "cookie"?

A "cookie" is a piece of information, usually small and identified by a name, which may be sent to your browser by a website you are visiting. Your web browser will store it for a period of time, and send it back to the web server each time you log on again.

Different types of cookies are placed on the sites:

  • Cookies strictly necessary for the proper functioning of the site
  • Cookies deposited by third party sites to improve the interactivity of the site, to collect statistics

Learn more about cookies and how they work

The different types of cookies used on this site

Cookies strictly necessary for the site to function

These cookies allow the main services of the site to function optimally. You can technically block them using your browser settings but your experience on the site may be degraded.

Furthermore, you have the possibility of opposing the use of audience measurement tracers strictly necessary for the functioning and current administration of the website in the cookie management window accessible via the link located in the footer of the site.

Technical cookies

Name of the cookie

Purpose

Shelf life

CAS and PHP session cookies

Login credentials, session security

Session

Tarteaucitron

Saving your cookie consent choices

12 months

Audience measurement cookies (AT Internet)

Name of the cookie

Purpose

Shelf life

atid

Trace the visitor's route in order to establish visit statistics.

13 months

atuserid

Store the anonymous ID of the visitor who starts the first time he visits the site

13 months

atidvisitor

Identify the numbers (unique identifiers of a site) seen by the visitor and store the visitor's identifiers.

13 months

About the AT Internet audience measurement tool :

AT Internet's audience measurement tool Analytics is deployed on this site in order to obtain information on visitors' navigation and to improve its use.

The French data protection authority (CNIL) has granted an exemption to AT Internet's Web Analytics cookie. This tool is thus exempt from the collection of the Internet user's consent with regard to the deposit of analytics cookies. However, you can refuse the deposit of these cookies via the cookie management panel.

Good to know:

  • The data collected are not cross-checked with other processing operations
  • The deposited cookie is only used to produce anonymous statistics
  • The cookie does not allow the user's navigation on other sites to be tracked.

Third party cookies to improve the interactivity of the site

This site relies on certain services provided by third parties which allow :

  • to offer interactive content;
  • improve usability and facilitate the sharing of content on social networks;
  • view videos and animated presentations directly on our website;
  • protect form entries from robots;
  • monitor the performance of the site.

These third parties will collect and use your browsing data for their own purposes.

How to accept or reject cookies

When you start browsing an eZpublish site, the appearance of the "cookies" banner allows you to accept or refuse all the cookies we use. This banner will be displayed as long as you have not made a choice, even if you are browsing on another page of the site.

You can change your choices at any time by clicking on the "Cookie Management" link.

You can manage these cookies in your browser. Here are the procedures to follow: Firefox; Chrome; Explorer; Safari; Opera

For more information about the cookies we use, you can contact INRAE's Data Protection Officer by email at cil-dpo@inrae.fr or by post at :

INRAE

24, chemin de Borde Rouge -Auzeville - CS52627 31326 Castanet Tolosan cedex - France

Last update: May 2021

Menu Logo Principal logo Université Clermont Auvergne & associés

Human Nutrition Unit

Zone de texte éditable et éditée et rééditée

Daniel Béchet

Daniel Béchet's profile
DanielBechet

Field of research

Aging affects most tissues and physiologic functions, but one of the most affected organs is the skeletal muscle. The age-related decline in muscle mass and function (sarcopenia) increases the risk of impaired mobility, poor balance, falls, and loss of autonomy. Skeletal muscle, which is the most abundant tissue in the adult body, also plays a central role as a reserve for energy and amino acids, and is a major site of fatty acid oxidation, carbohydrate metabolism and maintenance of heat homeostasis. Hence, age-related loss of muscle mass also triggers severe metabolic side effects, including metabolic syndrome and frailty in the elderly. Independently of other risk factors or disease, low skeletal muscle mass or strength is now reported to be a predictor of morbidity and mortality. A clear understanding of the mechanisms of sarcopenia through the identification of selective biomarkers is thus of paramount importance in ensuring quality of life in the old age.

To provide an integrative view of sarcopenia in human, we have undertaken top-down differential proteomic approaches, and we combined proteomics, transcriptomics, immunohistology and mass spectrometry molecular imaging to study unique cohorts of elderly subjects, and several sub-cohorts with age-related pathologies (hypertension, metabolic syndrome, etc.). Our studies provide major information about fiber type, morphology, oxidative metabolism, lipid droplets, apoptosis, capillarization, satellite cells and fibrosis of the extracellular matrix, together with mass spectrometry molecular imaging, and state of the art transcriptomic and 2D and shot-gun proteomic analyses. Using these methodologies, we identified fiber type-specific alterations and many potential biomarkers of muscle chronological aging and age-related pathologies.

Research activities

Immunohistological analyses performed with muscle biopsies indicated that: (1) healthy aging is associated with atrophy and deformation of myofibres (mostly type-II) and with slight accumulations of intramyocellular lipid droplets; (2) hypertension in the elderly is further linked with perturbations in muscle capillarization and mitochondrial oxidative activities; and (3) metabolic syndrome with changes in lipid profiles as revealed by molecular imaging. We also demonstrated that age-related increase in apoptosis in muscle is (i) not confined to myofibres, but (j) of significant importance in satellite cells, and (k) preponderant in capillary endothelial cells, which may alter the delivery of nutrients and oxygen and the removal of toxic metabolic products.

To better understand the mechanisms of aging, we have developed several differential proteomic approaches and settled for muscle ‘shot-gun’ proteomics and mass spectrometry molecular imaging to study unique cohorts of elderly subjects. Overall our investigations assessed more than 2500 proteins and identified nearly 100 (including 53 new) potential biomarkers of muscle chronological aging in Human. Our results indicate important modifications in cytosolic, mitochondrial and lipid energy metabolism, which may relate to dysfunctions in old muscle force generation. Some differentially expressed proteins were linked to the sarcomere and cytoskeleton, which may account for alterations in contractile properties. In line with muscle contraction, we also identified proteins related to calcium signalling. Muscle ageing was further characterized by the differential regulation of several proteins implicated in cytoprotection, detoxification and ion homeostasis. Notably, many of the differentially expressed proteins are central for proteostasis, including heat-shock proteins and proteins involved in proteolysis. To our knowledge, these studies describe the most extensive proteomic analysis of muscle aging in humans.

back