Low-molecular-weight water-soluble chitosan on the impact of blood sugar in diabetic mice

Key words :chitosan; diabetes; blood sugar; mice



[Abstract] Objective To study the water-soluble low-molecular-weight chitosan on blood sugar in diabetic mice and its mechanism. Methods 42 mice were randomly divided into normal control group (10), diabetes control group (8), chitosan low-dose treatment group (8), chitosan dose in the treatment group (8), Shell PG high-dose treatment group (8), respectively saline, 10 g / L (250 mg / kg) of chitosan, 20 g / L (500 mg / kg) of chitosan, 40 g / L (1 000 mg / kg) oral administration of chitosan in a row 28 d, observed changes in blood sugar in mice, and immunohistochemical methods to observe islet β cells. The results of chitosan dose and high dose treatment group to lower blood sugar, and diabetes compared to the control group, there was a significant difference (F = 29.55, q = 5.13,7.03, P <0.01); chitosan high-dose treatment group islet β cells Diabetes compared with the control group increased. Conclusion of water-soluble chitosan has a lower blood sugar in diabetic mice, which may be related to the promotion of islet β cell proliferation-related.



[Key words] chitosan; diabetes; blood sugar; mice



EFFECTS OF LMWS-CHITOSAN ON BLOOD GLUCOSE IN DIABETIC MICE



YAN CHUN-LING, LIU WAN-SHUN, LIU BING



(Department of Pathophysiology, Qingdao University Medical College, Qingdao 266021, China)



[ABSTRACT] ObjectiveTo investigate the effects of LMWS-chitosan on blood glucose in diabetic mice. MethodsThe mice were divided into normal control group (10 mice), diabetic control group (8 mice), low-dose-treated group, medium-dose - treated group and high-dose-treated group. Intragastric administration with normal saline, chitosan in different doses, ie 10 g / L (250 mg / kg), 20 g / L (500 mg / kg), and 40 g / L ( 1 000 mg / kg), were carried out separately for different groups for 28 days. The levels of blood glucose were measured and the changes of pancreatic islet β cells were observed using immunohistochemical method. ResultsThe blood glucose levels in medium-dose and high - dose group declined, the differences were significant as compared with the diabetic control group (F = 29.55; q = 5.13,7.03; P <0.01). The number of pancreatic islet β cell in high-dose group was sig-nificantly higher than that in diabetic control group. ConclusionLMWS-chitosan could reduce the level of blood glucose in dia-betic mice, which may be related to the proliferation of pancreatic islet β cells.



[KEY WORDS] chitosan; diabetes mellitus; blood glucose; mice



Low-molecular-weight water-soluble chitosan is a safe and reliable natural biological activity of polysaccharide, at home and abroad in recent years relating to chitosan for the treatment of diabetes increased for prevention and treatment of diabetes to create a new way. This study was to explore low-molecular-weight water-soluble chitosan on blood sugar in diabetic mice and its possible mechanism for the clinical treatment of diabetes to provide new ideas and theoretical basis.



1 Materials and Methods



1.1 low-molecular-weight materials, water-soluble chitosan (LMWS-chitosan), molecular weight range of 2 000 to 3 200, the group prepared its own; STZ-(STZ), in the purchase of Sigma Corporation; blood glucose meter from Germany Production; mice, body mass (18 ± 2) g, male, purchased in the city of Qingdao Institute for Drug Control; SABC immunohistochemistry kit, purchased in the Wuhan Bo Shide biological Limited.



1.2 Methods



1.2.1 diabetes animal model of group selection and preparation of 50 mice, familiar environment after the purchase of 1 week. First mice were divided into two groups, normal control group (A), 10, 40 diabetic model group. STZ will be soluble in pH of 4.5 to 0.1 mol / L of citric acid - sodium citrate buffer, the match concentration 20 g / L of the solution. Model mice by intraperitoneal injection of STZ for the 200 mg / kg; A group of mice injected with normal saline equivalent to observe the changes in the mice. 72 h after the end of mouse check blood glucose by enzymatic determination of blood glucose test instrument, blood glucose concentrations higher than 11.1 mmol / L model for success in mice. According to the concentration of blood sugar and body mass in diabetic mice a preliminary screening of selected blood sugar and body mass concentration difference between the smaller diabetic mice, and were divided into four groups, namely, diabetes mellitus in the control group (B group), Shell PG low-dose treatment group (C group), chitosan dose in the treatment group (D), chitosan high-dose treatment group (E). B, C, D, E group with normal saline, respectively, 10 g / L (250 mg / kg) of chitosan, 20 g / L (500 mg / kg) of chitosan, 40 g / L (1 000 mg / kg) per day oral administration of chitosan, for 28 d, ig 28 d after the detection of the mice in each group 4 Yanchun Ling, LIU Wan-shun, Liu Bing, and so on. Low-molecular-weight water-soluble chitosan on blood sugar in diabetic mice 353 affect the level of blood sugar and body mass.



1.2.2 Immunohistochemical detection of oral administration after the end of each of the groups of mice were killed, pancreas tail of the pancreas take part fixed, paraffin section, with SABC method showed that islet β cells, were observed.



1.2.3 Statistical analysis to the results of x ± s said that the group used to compare paired t test and analysis of variance.



The results 2



2.1 animal model of 72 h after STZ injection, the mice elevated blood sugar, failed to remove mold in mice 3, 35 mice were successful model, the model mice were significantly higher than normal blood glucose control group (t = 20.87, P <0.01).



2.2 different concentrations of chitosan on the impact of oral blood glucose in mice 28 d after the end of the, B Group 2 mice died, the rest are to survive. Before treatment, B, C, D, E blood sugar mice in each group were not significantly different. After treatment, B, C group were not significantly different (F = 29.55, q = 2.43, P> 0.05); D, E and Group B group the difference was significant (q = 5.13,7.03, P <0.01); C , E between the two groups of comparison, the difference was significant (q = 4.59, P <0.01). Table 1.



Table 1 with different concentrations of chitosan on blood sugar levels in diabetic mice the impact of (slightly)



2.3 immunohistochemistry results of the Group A section of mouse insulin-positive cells more positive response to a product at the cytoplasm, Brown was black; B group of insulin-positive cells significantly reduced, a small amount of residual cells in the immune response than the color of the product Shallow; C group of insulin-positive cells of the immune response and the number of colors with the B group there was no significant difference; D and Group E immunoreactive cells than the B group increased.



3 discussion



Diabetes is a cause and pathogenesis of endocrine not yet clear - metabolic diseases, mainly due to lack of insulin secretion absolute or relative lack of target cells, as well as lower insulin sensitivity on the rise. According to the pathogenesis of diabetes is divided into different type 1 and type 2 [2], the experimental use of intraperitoneal injection of STZ-induced diabetic mice islet β cell damage, the absolute lack of insulin. Clinically, this type of diabetes patients using insulin injections of the main treatment, medication side effects and the incorrectly Yi Zhi Yi long-term resistance, therefore, to find a new, safe and reliable material must be hypoglycemic. Chitosan is a polysaccharide biopolymer, immune regulation, cancer and multiple functions such as blood fat, there is widespread use of Chinese medicine [3,4]. However, chitosan molecular weight of large, can not dissolve in water, its application subject to certain restrictions. Water-soluble chitosan is a certain degree of chemical modification made soluble in water and to maintain its original biological function of the polysaccharide derivatives. In this paper, experimental results show that the application of high-dose and dose of water-soluble chitosan diabetic mice for a period of time after treatment, the mice decreased blood sugar, and low-dose treatment group decreased blood sugar was not obvious, that water-soluble chitosan Has a hypoglycemic effect, and this effect was dose-dependent. Documents have reported that chitosan on alloxan-induced high blood sugar mice have a significant role in lowering blood sugar, but the mechanism is not clear. In order to preliminary explore the chitosan hypoglycemic mechanism of action, this article experimental mice in each group of islet β cells of the immune staining, showed that diabetes control group of mice with normal pancreatic islet β cells in the control group compared to a significant reduction, This proves that the damage is indeed STZ islet β cells, resulting in reduced secretion of insulin caused by hyperglycemia. , High doses of chitosan in the treatment group of mice islet β cells in diabetic than in the control group increased significantly, which we speculate that chitosan may have to promote islet β cell proliferation, and its drop of diabetes in mice Sugar may be relevant.