The Effect And Mechanism Of Chit-Oligosaccharide/Collagen Composite Gels On Pre-Osteoblastic MC3T3-E1s

Chit-oligosaccharide(COS) is a kind of amino-glucose molecules with ?-1, 4 glycosidic bonds, which prepared by either chemical or enzymatic decomposing method from chitosan. Compared with chitosan, COS is a low-molecular, water-soluble mass higher biological activity, more easily absorbed by human body and can directly interact with cells. COS has a variety of biological functions, which is connected with the degree of polymerization.In this paper, collagen and chit-oligosaccharide composite hydrogel(Col/COS) was constructed. The effects of collagen/COS composite gels on the growth, proliferation and osteogenic differentiation of MC3T3-E1 s were measured via MTT method, laser scanning confocal microscopy, ALP kit and RT-PCR. Then the collagen/mono COS composite gels were constructed, the effects of different monosaccharide composite gels system on the growth, proliferation and osteogenic differentiation of MC3T3-E1 s were also studied. At last, the difference effects on cells proliferation and differentiation which caused by different degree of polymerization of the polysaccharide were explored. And the mechanism of MC3T3-E1 differentiation which influenced by oligosaccharides has carried too. The results showed that:(1) The effect of collagen/COS composite gels on the cell growth, adhesion, proliferation and osteogenic gene expression has a certain degree of promotion which compared with that of pure collagen gels. And the promoting effect relevant to that content of COS in composite gels.(2) The effects of collagen/mono COS composite gels on MC3T3-E1 s growth, proliferation and bone related gene expression showed a certain promotion compared with that of pure collagen gels. And that of collagen/COS5 gels was higher. This means that the COS5 released from collagen/COS5 gel can promote cell proliferation and accelerate osteogenic differentiation.(3) The COS(molecular weight is 413.33, 610.99, 808.64, 1006.30, 1203.96 and 1405.23), chitosan(molecular weight is 3500 and 5000) has very good stimulative effect on the proliferation of osteoblasts and osteogenic differentiation compared with the control group. However, chitosan(molecular weight is 200000) inhibited cell proliferation and osteogenic differentiation in our study.