INBIOSUR   25013
INSTITUTO DE CIENCIAS BIOLOGICAS Y BIOMEDICAS DEL SUR
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
VDR dependent effects on myogenesis induced by 1,25(OH)2D3-glycosides from Solanum glaucophyllum leaves extract (SOLBONE A; HERBONIS AG) and synthetic 1,25(OH)2D3
Autor/es:
PARDO, VG; BUITRAGO, C; IRAZOQUI, P; BACHMANN, H; DE GENARO, P; DE BOLAND, AR
Lugar:
Boston
Reunión:
Workshop; 19th Workshop on Vitamin D; 2016
Resumen:
The presence of glycoside derivatives of 1a,25(OH)2D3 endows plants to gradual release of the free bioactiveform of 1a,25(OH)2D3 from its glycoconjugates by endogenous animal tissue glycosidases. This results inincreased half-life of the hormone in blood when purified plant fractions are administered for therapeuticpurposes. In this work, we compared the effects of 1a,25(OH)2D3-glycosides enriched natural product (Solbone A)from Solanum glaucophyllum leaf extract with synthetic 1a,25(OH)2D3 in muscle cells C2C12 undergoingdifferentiation and the role of vitamin D receptor (VDR) on this process. For these, differentiation markers andmyogenic parameters were studied. Results showed that Solbone A and synthetic 1a,25(OH)2D3 increased VDRprotein expression at 10 nM (50 and 30 %, respectively). Both compounds induced the expression of tropomyosin(20%), a protein involved in skeletal muscle contraction. In addition, the protein expression of myosin heavy chain(MHC), a marker of fiber production in muscle cells, was increased 50 % at day 4 of differentiation. Moreover,Solbone A, as well as synthetic 1a,25(OH)2D3t augmented the index fusion of cultured muscle fibers. In order toexplore the dependence of VDR on C2C12 differentiation, cells were stable transfected with a shRNA againstVDR Cells undergoing differentiation were treated with Solbone A and synthetic 1a,25(OH)2D3 (10 nM, 48 h).Micrographs of control and treated cells, showed that VDR expression is essential for C2C12 differentiation.Furthermore? Western blot and qRT-PCR analysis indicated that VDR expression was greatly decreased in VDRknockdown cells Also myogenin, another differentiation marker protein which we have previously shown toincrease with both compounds, was absent in VDR knockdown C2C12 cells. In conclusion, these resultsdemonstrated that VDR expression is crucial for C2C12 differentiation. More important, Solbone A exhibit at leastequal or greater effects on early myoblast differentiation as the synthetic hormone suggesting that plantglycosides could be an effective substitute to promote muscle growth.