CIRCULATING BIOACTIVES RESULTING FROM TOTUM-854 ABSORPTION IN HUMANS PROTECTS PRIMARY HUMAN ENDOTHELIAL CELLS AGAINST LIPOTOXICITY: LESSONS FROM AN ORIGINAL EX VIVO CLINICAL TRIAL

Abstract

Objective: TOTUM-854 is a patented plant blend extract characterized for its polyphenol-rich content that supports hypertension prevention in preclinical studies. However, clinically validated approaches and further investigations on the mode of action at the cellular level especially in humans are required for optimized care management. In this study, we designed an ex-vivo clinical innovative approach considering the circulating metabolites produced by the digestive tract following the ingestion of TOTUM-854 in humans. Design and method: Human serum was collected in healthy subjects before and following acute intake of 3.71g of TOTUM-854. Availability of circulating metabolites was confirmed and characterized by UPLC-MS. Human serum enriched with metabolites deriving from TOTUM-854 absorption was further incubated with human endothelial cells (HUVEC), pretreated or not with palmitate (200 μM). In such lipotoxic environment, HUVEC behavior was monitored to determine whether and how TOTUM-854 metabolites may improve vascular response in humans. Results: In the presence of the human metabolites from TOTUM-854, HUVECs were protected from an induced lipotoxic stress. No effect on cell toxicity was detected in the presence of enriched sera. HUVEC protection was characterized by (1) decreased ACE-1 activity (-32% p<0.0001); (2) the inhibition of oxidative stress with decreased ROS (-12% observed by DCFDA, and by DHE fluorescent microscopy) as well as decreased Nox2 gene expression (-6,7 fold change vs palmitate, p<0.01); (3) the inhibition of inflammatory response, with a decrease in IL-1↓ release (-37% compared to palmitate, p<0.001) and decreased MCP-1 et VCAM-1 gene expression (-93% p<0.001 and -77% p<0.001 respectively). All together, these data provide new biochemical mechanisms for a protective role of TOTUM-854 in human endothelial cells. Conclusions: Using a pioneering clinical ex vivo approach considering the circulating and bioavailable actives, we give clues on the role of metabolites produced following TOTUM-854 intake in humans in vascular protection.