After a 6-day osteogenic induction, the murine MC3T3-E1 cells were
incubated using serum-free medium, which contained Rb2 and/or H2O2
for 2 days. The expressions of RANKL and IL-6 in culture medium were
tested using the sandwich ELISA assay kit according to the manufacturer's
instructions. The total protein consistencies were measured using the
Bradford protein assay method.