Genistein is a widely studied phytoestrogen. The effects of genistein on myoblasts were reported long ago, but the conclusions are controversial. In this study, we evaluated the effects of different concentrations of genistein on C2C12 myoblasts.

Genistein treatment promoted myoblast proliferation in a dose-dependent manner in the concentration range of 0–2 µM/L, reaching its maximum effect at 2 µM/L. Proliferation then declined, and a concentration higher than 20 µM/L showed significant inhibition. In addition, genistein treatment promoted myoblast differentiation at a dose of 10 µM/L. However, at treatment concentrations higher than 10 µM/L, the effect on myoblast differentiation was rapidly inhibited as the concentration increased.

Genistein treatment also down-regulated the expression of miR-222, resulting in increased expression of its target genes, MyoG, MyoD, and ERα and thereby promoting myoblast differentiation.

Our results suggest that genistein has a dose-dependent and bidirectional regulation effect on myoblast proliferation and differentiation. We also found that genistein is a miRNA inducer, and it specifically affects the expression of miR-222 to regulate myoblast differentiation.

金雀异黄素是被广泛研究的植物雌激素。金雀异黄素对成肌细胞的作用很早以前就已有报道，但结论尚有争议。在这项研究中，我们评估了不同浓度的染料木黄酮对C2C12成肌细胞的影响。

Genistein处理在0–2 µM / L的浓度范围内以剂量依赖性方式促进成肌细胞增殖，在2 µM / L时达到最大作用。然后增殖下降，并且浓度高于20 µM / L时显示出明显的抑制作用。另外，金雀异黄素处理以10 µM / L的剂量促进成肌细胞分化。但是，当处理浓度高于10 µM / L时，随着浓度的增加，对成肌细胞分化的影响会迅速受到抑制。

Genistein处理还下调了miR-222的表达，导致其靶基因MyoG，MyoD和ERα的表达增加，从而促进了成肌细胞的分化。

我们的结果表明，染料木黄酮对成肌细胞的增殖和分化具有剂量依赖性和双向调节作用。我们还发现金雀异黄素是miRNA的诱导剂，它特别影响miR-222的表达以调节成肌细胞的分化。