We aimed to evaluate the effects of lactoferrin (LF) on the osteogenic differentiation and related gene expressions of mouse embryonic osteoblast precursor cells MC3T3-E1 under mechanical strain. MC3T3-E1 cells were randomly divided into control, strain loading, LF and strain loading + LF groups. Alkaline phosphatase (ALP) activity was measured. Cytoskeletal morphology was measured by rhodamine-phalloidin staining. Formation of mineralized nodules was observed by alizarin red staining. The expressions of differentiation-related genes type I collagen (COL-1), interleukin-6 (IL-6) and osteocalcin (OCN) were determined by RT-PCR, and those of p-Runx2 and p-ERK1/2 proteins were detected by Western blotting. The number of ALP positive cells and expressions of OCN, COL-1 and IL-6 were significantly elevated (P<0.05). The optical density of strain loading + LF group was higher than those in strain loading and LF groups after incubation for 4 and 7 days (P<0.05). The cell volume and extension range were elevated in strain loading + LF group compared with those in strain loading group. The amount of mineralized nodules in strain loading + LF group was significantly higher than those in strain loading and LF groups, while it was slightly higher in LF group than that in strain loading group. The expressions of p-ERK1/2 and p-Runx2 in strain loading + LF group exceeded those in strain loading and LF groups (P<0.05). The synergistic action of LF and mechanical strain can effectively promote the proliferation, differentiation and mineralization of osteoblasts, probably being associated with the ERK1/2 signaling pathway.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.