On the clinical side, our work focuses on cardiovascular pathologies. For the experimental aspects, we aim to extent, in collaboration with the Department of Cardiology (Pr Jacques Mansourati) of the CHRU of Brest, knowledge in the mechanisms involved in cardiovascular pathologies and to evaluate prevention strategies such as the use of physical activity, nutrition and therapeutic substances (ex: statins).
A part of the clinical studies concerns the effectiveness of the antithrombotics on coronary artery disease and their risks. The use of new generations of coronary stents as well as the role of hybrid strategies (angioplasty and coronary surgery) in the management of the coronary heart disease are also studied. These studies involve some national and international collaborations leading high-level publications.
Prevention through physical activity :
It is recognized that physical activity is beneficial in primary and secondary prevention of cardiovascular diseases. These beneficial effects are likely mediated by various mechanisms including those involved in vascular function, mitochondrial function and redox status. Several animal models are used for this approach.
Endothelial function /redox status:
We are studying physical activity and nutrition beneficial effects at vascular, myocardial and muscular levels with several murine endothelial dysfunction models. In this way, we observed a positive effect of moderate training on eNOS uncoupled. Furthermore, dietary supplementation of antioxydants associated with intensive training prevent the increase of eNOS expression in the myocardial tissue and improves redox status.
Mitochondrial function and reactive oxygen species (ROS):
Chronic physical activity benefits at cardio-vascular level are mediated in part by the metabolic plasticity of skeletal muscle. Chronic aerobic exercise causes skeletal muscle adaptation as mitochondrial biogenesis, resulting by increased muscle oxidative capacity. The mechanisms underlying these metabolic responses and their kinetics of implementation are not yet elucidated for which work within the laboratory is ongoing. Reactive oxygen species produced mainly at the mitochondrial level should be involved in these processes by activating signaling pathways of the phenotypic adaptations (angiogenesis, muscle hypertrophy, mitochondrial biogenesis). If free radical production is necessary for these adaptations, it must be also tightly regulated to avoid oxidative stress. The role of chronic exercise on tolerance of cardiac muscle tissue to oxidative stress is a subject still in full investigation.
A comparative approach in different species (rat/fish) have shown that moderate training exercise improve muscle metabolic and free radical profiles. Whatever the species, training seems to be more beneficial in the male than in the female skeletal muscle in term of mitochondrial energy efficiency and oxidative stress resistance.
The main goal of our project is to determine the time course of transcriptional and biochemical adaptations of mitochondrial function (enzyme activities, energy efficiency etc…) as well as muscular and cardiac redox state evolution during chronic exercise.
UFR Sciences et Techniques, Université de Bretagne Occidentale
6 Av. Le Gorgeu - CS 93837
29238 BREST Cedex 3 - FRANCE
Directrice : C.MOISAN (+332.98.01.62.63)
Directrice adjointe: M-A.GIROUX-METGES(+332.98.01.80.67)