Cosmet'eau-Changes in the personal care product consumption practices: from whistle-blowers to impacts on aquatic environments.

The Cosmet'eau project (2015-2018) investigates the "changes in the personal care product (PCP) consumption practices: from whistle-blowers to impacts on aquatic environments." In this project, the example of PCPs will be used to understand how public health concerns related to micropollutants can be addressed by public authorities-including local authorities, industries, and consumers. The project aims to characterize the possible changes in PCP consumption practices and to evaluate the impact of their implementation on aquatic contamination. Our goals are to study the whistle-blowers, the risk perception of consumers linked with their practices, and the contamination in parabens and their substitutes, triclosan, and triclocarban from wastewater to surface water. The project investigates the following potential solutions: modifications of industrial formulation or changes in consumption practices. The final purpose is to provide policy instruments for local authorities aiming at building effective strategies to fight against micropollutants in receiving waters.

Control of actin dynamics by p38 MAP kinase - Hsp27 distribution in the lamellipodium of smooth muscle cells.

We investigated the role of the p38 mitogen-activated protein kinase (p38 MAPK) in the PDGF-BB-induced cytoskeleton remodeling that occurs during the migration of porcine aortic smooth muscle cells (SMC). We showed that p38 MAPK controlled the polymerization of actin that is required for PDGF-induced lamellipodia formation and migration. To investigate the mechanism of action of p38 MAPK, we explored its cellular localization and that of its indirect substrate, the heat shock protein Hsp27, during SMC spreading on fibronectin in the presence and absence of PDGF. Spreading of SMC on fibronectin activated p38 MAPK in a sustained manner only in the presence of PDGF. In these conditions, Hsp27 and p38 MAPK were localized all over the lamellipodia. A transiently phosphorylated form of p38 MAPK was observed at the leading edge, whereas p38 MAPK remained phosphorylated at the base of the lamellipodia. Phosphorylated Hsp27 was excluded from the leading edge and restricted to the base of the lamellipodia. These results were confirmed by Triton X-100 extraction of particulate membrane fraction. Displacement of Hsp27 from the leading edge by cytochalasin D treatment suggests that nonphosphorylated Hsp27 caps barbed ends in vivo. Our data indicate that nonphosphorylated Hsp27 might contribute to the formation of a short, branched actin network at the leading edge, whereas phosphorylated Hsp27 might stabilize the actin network at the base of lamellipodia, which is composed of long, unbranched actin filaments.