A soluble and active form of Wnt-3a protein is involved in myogenic differentiation after cholesterol depletion

Cholesterol is one of the major lipids of plasma membranes. Recently, we have shown that cholesterol depletion by methyl-β-cyclodextrin (MβCD) induces the activation of the Wnt/β-catenin pathway and enhances myogenic differentiation. Here, we show that MβCD-conditioned media accelerates myogenesis in a similar way as MβCD does, suggesting that the effects induced by MβCD could be caused by soluble factors present in the culture medium. Soluble Wnt-3 protein is significantly enhanced in MβCD-conditioned medium. Wnt-3a-enriched media induces myogenesis as much as MβCD does, whereas Wnt-5a-enriched media inhibits. We suggest that Wnt-3a is involved in the myogenic induction observed after cholesterol depletion.