Abstract: The present invention concerns a C-glucosidic ellagitannin compound or a metabolite thereof for use for altering the supramolecular arrangement of actin in an individual suffering from osteoporosis, cancer, bacterial infection, or viral infection. It also pertains to pharmaceutical compositions comprising a C-glucosidic ellagitannin compound and/or metabolites thereof and one or more physiologically acceptable carriers. It finally concerns a C-glucosidic ellagitannin compound or a metabolite thereof, optionally detectably labeled, for in vitro use as a tool for studying cellular mechanisms involving actin, or for detecting F-actin in a cell.

Abstract: The present invention relates to a bone system model comprising a mineralized matrix and osteoblasts, chararacterized in that the osteoblasts are deposited onto the matrix so as to form a layer at confluence and/or nodules, and the osteoclasts are deposited onto said layer and/or said nodules, and also to bone system models affected by various pathologies. The invention also covers the uses for carrying out screenings and tests for aggressiveness and for toxicity.