The purpose of this study was to clarify the effect of hyaluronan (Hya) and sulfated hyaluronan (SHya) on rat calvarial osteoblast (rOB) cells proliferation and differentiation in vitro. rOB cells were cultured in the presence of Hya with different molecular weights (0.2, 2, 30, 90, 120 x 104) for 10days. Hya did not affect the proliferation of rOB cells. However, SHya suppressed the proliferation of rOB cells. The alkaline phosphatase (ALPase) activity of rOB cells cultured with SHya for 10 days was significantly enhanced in comparison with control (in the absence of polysaccharides) and with Hya. Hya suppressed the ALPase activity of rOB cells. As a result, SHya can control rOB cells proliferation and differentiation. SHya suppressed the rOB cells proliferation in a few culture days and promoted the differentiation. It was suggested that these effects were based on the sulfate groups of SHya. Therefore, it is considered that SHya is useful for the biomedical material, which promotes the differentiation of rOB cells.
