The passive stiffness of elastic arteries is mainly determined by two major extracellular matrix proteins of the arterial wall, i.e. elastin and collagen. Elastin provides reversible extensibility during cyclic loading of the cardiac cycle, while collagen provides stiffness and strength at high pressures. Loss of elasticity and induced consequences on the vascular function are observed in normal ageing, and in syndromic elastogenesis-related genetic diseases which include Williams-Beuren syndrome, supra-valvular aortic stenosis and autosomal dominant cutis laxa. Recent studies have also shown it can be associated with pathological conditions such as the sleep apnea syndrome (SAS). Knowing that SAS concerns about 10% of the general population and affects 20% in the elderly, in 2015 in France, 837,000 people were treated for SAS. Williams-Beuren syndrome is a rare disease but represents 3,000 people in France and is estimated at 300,000 patients over the world. The age-related cardiovascular dysfunctions, involving elastic fibre alterations, concern a large and growing part of the population. If we could introduce new elastin in the existing elastic scaffold of arteries, and if this provides increased elasticity, we would have a revolutionary treatment related to a very large market in the pharmaceutical field. Arterylastic project aims at restoring the function and mechanical properties of blood vessels using an original synthetic elastic protein recently developed by the principal investigator (“DHERMIC”, ANR 2012-2016). This represents a very important breakthrough since this compound might serve as an elastic molecular prosthesis in tissues to compensate or restore the lack of elasticity. To reach this ambitious goal, the Arterylastic project will investigate and optimize the following properties of this synthetic compound: - delivering the right signal to cells with no deleterious effect; - reaching the right location through the endothelial barrier; - being integrated into elastic fibres within vascular walls; - improving arterial wall elasticity and/or physiological parameters in relevant animal models; - developing an injectable formulation of the compound with a pharmaceutical grade. We have large convincing data set available on skin for the synthetic elastic protein (DHERMIC project) and we recently obtained preliminary very promising results for blood vessel integration in fish and mouse. The success of the proposal will also rely on strong complementarities between the three internationally recognised academic partners: LBTI is expert in biology of elastic fibres and therapeutic engineering; HP2 has a strong expertise in vascular physiology and in elastin hemizygous and intermittent hypoxia mice models mimicking sleep apnea syndrome (SAS); and ARMINES-CIS is a very active laboratory in the field of biomechanics and numerical modelling of soft tissues. To ensure a certified pharmaceutical grade formulation, the FRI Pharm facility core from Lyon hospital is involved in the project. After achieving the scientific investigations, a partnership with a pharmaceutic company will be addressed to allow for further industrial and clinical developments. Moreover, a startup company will be created in order to accelerate the industrial transfer and at mid-term to participate in local socio-economic dynamism.