Preparation Of Chitosan Guanidine Hydrochloride And Its Effects On HepG2 Cells Of Insulin Resistance

Metformin is the most preferred drug for the treatment of type 2 diabetes mellitus(T2DM)recommended by clinical guidelines all over the world.Chitosan is natural polysaccharide which has been proved to have hypoglycemic effect.Introducing the structure of metformin into the chitosan molecule can not only strengthen their hypoglycemic ability,but also improve the bioavailability of metformin drugs.In view of the above,chitosan guanidine chloride was prepared,and the possible effect of it on the key biological factors of cells of insulin resistance was investigated in the molecular level.Chitosan guanidine chloride wsa prepared of chitosan and dicyandiamide via both traditional chemical method and microwave method.The effect of reaction temperature,reactant molar ratio,reaction time,pH and other factors have the on the of reaction yield and substitution degree of the final product was sdudied and analyzed.The optimal preparation conditions were determined as: pH value is 1,the reaction of chitosan with dicyandiamide molar ratio is 1:3,the reaction time is 15 min,and the reaction temperature is 100 ?.Then the structure and composition of the product was analyzed by the methed of ultraviolet spectrum,infrared spectrum analysis and element analysis.HepG2 cells were induced by insulin of high level to set up insulin resistance model,and cell vitality and glucose consumption were used as evaluation indexes.The optimum conditions of insulin resistance model building are: insulin concentration is 1×10-7 mol·L-1 and the acting time is 24 h.Then in vitro cytotoxicity test of chitosan guanidine chloride was tested,and avirulent samples were selected.The effect of chitosan guanidine chloride on glucose consumption,insulin receptor and the signal protein glucose transporters-2(GLUT-2)on insulin signaling pathway liver cells were investigated.Results showed that chitosan guanidine chloride can significantly improve the glucose consumption and protein expression of insulin receptor,and at the same time reduce the GLUT-2 transport protein expression,which prove that insulin resistance of Hep G2 cells can be effectively improved.Degree of substitution is one of the most critical factors,and concentration of the samples has no obvious correlation with this improvement.