Red yeast rice extracts increase the proliferation and differentiation of osteoblastic MC3T3‐E1 cells

Abstract

Red yeast rice (red koji) lowers cholesterol but other functional effects are yet to be proven. In this pilot study, we tested the effect of red yeast rice extracts on cellular proliferation and differentiation in osteoblastic MC3T3-E1 cells, a mouse calvaria osteoblast-like cell line. Red yeast rice powder obtained as cultures of Monascus purpureus on rice was methanol-extracted. MC3T3-E1 cells were cultured in the presence of α-MEM (vehicle control), rice/cooked rice extracts (control), or red yeast rice extracts in various levels and time sequences. The effect of red yeast powder on the cell proliferation and differentiation was evaluated by MTT assay and cell morphology. Red yeast rice extracts exhibited stimulatory effects on the cell growth and differentiation in a dose-dependent manner within the range of 1- 0.001 mg/ml, and the most pronounced effect was shown at the extract levels between 0.1-0.001 mg/ml for 24 hours. As cell culture time increased up to 15 days, cell growth decreased in high extract levels between 1–0.5 mg/ml. It was taken in consideration that if the osteoblasts would be cultured with optimal level (0.1-0.001 mg/ml) of red yeast rice extracts, the cell proliferation and differentiation would be stimulated. These results imply that red yeast rice extracts may have beneficial function for bone health through the stimulatory effect of osteoblast growth.