CrudePolysaccharidesExtractedFromSeveralMedicinalFungiExhibitHypoglycemicFunctionsinMice

1、Crude Polysaccharides Extracted From Several Medicinal Fungi Exhibit Hypoglycemic Functions in MiceAbstract:The hypoglycemic effects of crude polysaccharides extracted from five medicinal fungi were evaluated using alloxan-induced diabetic mice. High(1 g/kg) and low (0.5 g/kg) doses of polysaccharid

2、es extracted from Cordyceps taii and C. memorabilis caused significant (P0.01) decreases in mice blood sugar levels. Polysaccharides from Ganoderma lucidum and C. militaris fruit bodies both exhibited weak hypoglycemic effects at significance levels of P0.01 and P0.05 for high and low doses,respecti

3、vely. Polysaccharide extracted from mycelium of a Phellinus sp. was significantly (P10.0 mmol/L were selected as diabetic mice.1.7Mice treatment groupsTen untreated mice were designated as the normal group. Diabetic mice were divided randomly into 12 groups (10 mice in each group) that included a ne

4、gative control group (administered 10 mL/kg saline), a positive control group (administered 250 mg/kg metformin hydrochloride), and ten test groups administered either high (1 g/kg) or low (0.5 g/kg) doses of the different crude polysaccharide preparations. Stock solutions (prepared in saline) conta

5、ining either 1.0 g/10 mL or 0.5 g/10 mL of crude polysaccharide were used to administer high and low doses, respectively. Treatments were administered through stomach filling (10 mL/kg) every 24 h for 7 days along with normal feed and water. After the final stomach filling, mice were fasted for 24 h

6、 and blood samples were taken from eye veins. Serum was separated and blood sugar values were determined using the glucose oxidase method according to the manufacturer?s instructions.1.8Data analysisAll experimental data were subjected to statistical analysis by Excel software and the t-test.2 Resul

7、ts and analysis2.1Polysaccharide yieldsPolysaccharide yields from different fungi are shown in Table 1 (see the Chinese version). Highest polysaccharide yields (8.1%) were obtained from C. memorabilis mycelium whereas lowest yields (2.3%) were from G. lucidum fruit bodies.2.2Effect of crude polysacc

8、haride preparations on diabetic miceThe effects of the different polysaccharide treatments on diabetic mice are summarized in Table 2 (see the Chinese version). All of the samples exhibited hypoglycemic functions that were more pronounced in the higher dosage groups. Crude polysaccharide extracted f

9、rom mycelia of C. taii and C. memorabilis were most effective in lowering serum glucose levels. The impacts of both high and low dosages were significant at P0.01, and glucose levels in both the higher dosage groups were similar to the level observed in the positive control group treated with metfor

10、min, a common medicine for diabetics. In comparison, relatively weak effects were observed with crude polysaccharide extracted from fruit bodies of G . lucidum and C. militaris; the impact of high and low doses was significant at P0.01 and P0.05, respectively. No significant effect compared with neg

11、ative controls was observed with the test group given low doses of crude polysaccharide extracted from mycelium of Phellinus sp. although there was a significant impact (P0.05) in the group administered higher doses of this material.3 DiscussionThe cytotoxin alloxan damages pancreatic B -cells and i

12、s widely used to induce experimental diabetes in animals in order to test different compounds for hypoglycemic functions. In the present study, lower dosages (0.5 g/kg) of crude polysaccharide extracted from G. lucidum lowered blood glucose levels by 9.3% in alloxan-induced diabetic mice compared wi

13、th controls after one week of treatment. These findings are in agreement with previous reports by CHEN et al 4, and by ZHANG and FENG5 . However, our finding that crude polysaccharide from C. militaris at doses of 1.0 g/kg lowered glucose levels by 11.3% did not comply with the results of ZHANG et a

14、l. 6, although this may have been due to differences in the fungal strain and/or the animal model use in their investigation.C. taii, which contains various chemical components in common with C. sinensis 79, has previously been reported to possess immuno modulatory functions 10,11 ,whereas C. memora

15、bilis has been assigned nerve cell protecting properties 12,13, as well as antiseptic and cytotoxic activity 14 . However, as far as we are aware, this is the first report of hypoglycemic functions associated with crude polysaccharide material extracted from these two fungi. Both MCT and MCM exhibit

16、ed good hypoglycemic effects when used at higher dosages (1 g/kg). Our data showed that blood glucose was lowered to similar levels observed in mice given metformin hydrochloride, and suggest that these materials are worthy of further investigation.References1DU M, ZHANG S. Mechanism of edible funga

17、l polysaccharide on reducing blood sugar J. Journal of Microbiology ， 2007, 27( 2)：83-87. (in Chinese with English abstract) 2SHUN YF. Pharmacological action and application of edible fungus polysacchaides J . Journal of Medicine Community ，2006， 4(1)： 29-31. (in Chinese) 3TAO MH, PAN QL, ZHANG WM.

18、Test method for polysaccharides in medicial fungi J . Edible Fungi of China ， 2005，24(5)：37-38. (in Chinese)4CHEN WQ, HUANG JW, LUO LQ, et al. Studies on preventive effects of Ganoderma lucidum polysaccharide (GLP) against the formation of hyperlipidaemia in rats J . Chinese Journal of Gerontology ，

19、 2005，25( 8): 957-958. (in Chinese) 5ZHANG LZ, FENG L. Researching the mechanism of GLPs hypoglycemia J . Fujian Medical Journal ，2004， 26 (3)： 137-140. (in Chinese with English abstract)6 ZHANG GQ, HUANG YD, BIAN Y, et al. Hypoglycemic activity of the fungi Cordyceps militaris, Cordyceps sinensis,

20、Tricholoma mongolicum and Omphalia lapidescens in streptozotocin-induced diabetic ratsJ. Appl Microbiol Biotechnol, 2006, 72(6): 1152-1156.7 JIAO YC, LIANG ZQ, LIU AY . Studies on the anamorph of Cordyceps taii n polysaccharide J . Southwest China Journal of Agricultural Sciences ，1993，6( 1)：27-32 .

21、 (in Chinese with English abstract)8 LIU JL, LIU RY . Enhancement of Cordyceps taii polysaccharide on cellular immunological function in vitro J . Chinese Pharmaceutical Journal， 2001， 36(11) ：738-741 . (in Chinese with English abstract)9 LIU JL, FEI Y . Enhancement of Cordyceps taii polysaccharide

22、and Cordyceps pruinosa poly-saccharide on cellular immune function in vitro J . Immunological Journal ， 2001， 17( 3)： 189-191 . (in Chinese with English abstract)10 LI XM, LI YF. The cultivation and component analysis of Cordyceps taii mycelia J . Journal of Henan Agricultural Sciences, 2003,(12):44-46. (in Chinese with English abstract)11 GUO XY ,