Comparative actions of 1,25(OH)2D3-glycosides and synthetic 1,25(OH)2D3 during myogenesis

AMUSQUIBAR, A; IRAZOQUI, P; DE GENARO, P; GONZALEZ PARDO, V; BUITRAGO, C; BACHMANN, H; DE BOLAND, AR

Cordoba

Congreso; LII Reunión de SAIB; 2016

SAIB

The presence of glycoside derivatives of 1,25(OH)2D3 endows plants to gradual release of the free bioactive form of 1,25(OH)2D3 from its glycoconjugates by endogenous animal glycosidases. This results in increased hormone half-life in blood when purified plant fractions are administered for therapeutic purposes. In this work, we compared the effects of 1,25(OH)2D3-glycosides enriched natural product (Solbone A) with synthetic 1,25(OH)2D3 in skeletal muscle cells C2C12 undergoing differentiation and the role of vitamin D receptor (VDR) on this process. Results showed that Solbone A and 1,25(OH)2D3 (10 nM) increased VDR expression. To explore VDR dependence on C2C12 differentiation, cells were transfected with a shRNA against VDR and then treated with Solbone A or 1,25(OH)2D3 (10 nM, 48 h). qRT-PCR analysis indicated that VDR expression was greatly decreased and microphotographs showed that VDR knockdown cells failed to differentiate. Furthermore, likewise the synthetic hormone, Solbone A increases myogenin, a differentiation marker that was absent in VDR knockdown cells. In conclusion, our results demonstrated that VDR expression is crucial for C2C12 differentiation. Moreover, Solbone A exhibit equal or greater effects on early myoblast differentiation as the synthetic hormone suggesting that plant glycosides could be an effective substitute to promote muscle growth.