Anti‐inflammatory effect and bone induction ability of hainosankyuto in the human osteosarcoma cell line Saos‐2

ABSTRACT Aim Hainosankyuto is a traditional Japanese medicine known as Kampo. It is mainly used to treat skin pain and mucosal suppurative diseases. Hainosankyuto also alleviates pain resulting from local reddening and swelling and promotes pus discharge. Our previous cell culture and animal experiments demonstrated the anti‐inflammatory effect of hainosankyuto on periodontal disease (Kampo Med. 45, 601–607, 2018). Periodontal disease affects periodontal tissues, such as the gingiva and alveolar bone, due to inflammation. Our study aimed to evaluate the anti‐inflammatory effects of hainosankyuto on osteoblasts and assess whether this medicine affects their bone‐forming ability. Methods We examined the effect of hainosankyuto on the proliferation of the human osteosarcoma cell line Saos‐2 in vitro using 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide and DNA synthesis assays. We also evaluated its effect on interleukin (IL)‐8, type 1 collagen, and alkaline phosphatase (ALP) activity in these cells using enzyme‐linked immunosorbent assays and ALP assay. Results Hainosankyuto (1000 μg/mL) significantly induced Saos‐2 cell proliferation, suppressed IL‐8 production, and enhanced type 1 collagen production and ALP activity. Conclusion These results indicate that hainosankyuto regulates inflammation and metabolism in osteoblasts, resulting in the activity of early bone‐related biomarkers.