Anti-Hyperglycemic Activity of Shan Tang Ping an Ethanol Extract from Yew Tree in Diabetic Rats

Journal of Beijing Institute of Technology 2005, Vol. 14, No. 3Anti-Hyperglycemic Activity of Shan Tang Ping anEthanol extract from yew tree in diabetic ratsDENG YU-lid(邓玉林), SHENG Ling-huk盛灵慧), DAI Rongⅸ戴荣继),XU Xiao-yu(徐晓玉)School of Life Science and Technology Beijing Institute of Technology Beijing 100081, ChinaAbstract: The extracts of yew tree have showed unique anti-tumor and anti-leakematic activities. Taxol ex-tracted from it is effective against a variety of cancers such as ovarian cancer and breast cancer. However thehypoglycemic efficacy of the extract has not been reported yet so the effects of oral administration of yew treextracts on streptozotocin- induced diabetic rats were examined. Administration of shan tang ping( StP),afraction from the column separation of extract(450 mg/kg body weight), for 14 days reduced the serum glucose concentrations of fasted diabetic rats by 52. 4%. In addition, it also decreased the concentrations ofglyceride(Tg), total cholesterol( TC), and low density lipoprotein cholesterol LDL-C ). An oral glucosetolerance test(OGTT)was performed a significant improvement in glucose tolerance was observed in ratstreated with STP. These results suggest that STP has hypoglycemic properties and hypolipidemic action onstreptozotocin-induced diabetic ratsKey words: Jew tree streptozotocin hypoglycemic diabetes mellitusCLC number: R 965 Document code: A Article ID: 1004-057 2005 03-0323-05Diabetes mellitus is a multifactorial disease char- have shown unique anti-tumor and anti-leakematic ac-acterized by hyperglycemia and lipirotein abnormali- tivitieoweverthere is no report available in theties. According to WHo projections the prevalence literature for the anti-diabetic effect of jew tree exof diabetes is likely to increase by 35%,so it will tract. The present study is undertaken to investigatehave been to reach 300 million or more by the year the effect of shan tang ping StP ), an extract of20251. Although there are many drugs managing ew tree, on changes in serum glucose, serum lipiddiabetes they are either expensive( like insulin thia- profile oral glucose tolerance of strepozotocin-inducedzolidinediones )or having adverse effects like sulfonylureas ) Plant drugs are frequently considered toI Materials and methodsbe less toxic and side effects than synthetic ones. Insome countries many traditional practice medicinalThe leaves of vewe tree were obtained from Anplants are used to control diabetes mellitus]hui province in November 2002. The botanical idenAmong the natural plants, jew tree( taxaceae) tity was confirmed by Dr Deng Yu-lin. a dried specihas been used as a cure for cough rheumatism and men was stored in the Lab of Life science and Techintestines verminosis in the ancient times in China. In nology. Streptozotocin( stz) was obstained fromCompany Inc., St Louis, MOChen"and Ben Cao gang, etc. yew tree wasrecorded as a novel medical plant. The extracts of it frorH中国煤化tic kits were purchasedCNMHGroject High-TechnologyReceived 2004-03-22Sponsored by the National Natural Science Foundation( 20275005 30170336)BiographyDENGYu-linf1962-)professordoctoraladviserdeng(@bit.edu.cnJournal of Beijing Institute of Technology 2005, Vol. 14, No. 3Company Beijing China ) All other chemicals used group 3: diabetic rats STP 400 mg/kgfor this experiment were of analytical gradegroup 4: diabetic rats drug A 400 mg/kg i1.1 Preparation of Plant Extractsgroup 5: diabetic rats drug b 400 mg/kgThe air-dried leaves of yew tree were ground togroup 6: diabetic rats metformin 80 mg/kgAnimals were administeredThe homogenate was extracted with 95% glucose concentration was determined 2 h after theethanol. The solution was concentrated to dryness treatment on the lst 3rd and 5th day. The depenunder reduced pressure at 70 C yielding dark-brown dence of the anti-hyperglycemic effect on Stp dosageextracts, which is used as drug A. Subsequently the was further investigated. Diabetic rats were treatedextracts were subject to stepwise procedures for con- with different dosage of StP, and the treatment lastcentrating the active components. The crude extracts ed for 14 days. The effect of stp on glucose homewere defatted with petroleum and followed by the stasis was studied using normal rats. Twelveextraction with chloroform. The chloroform extracts wistar rats were divided into normal and StP groupswere further separated by the silica-parked column, For the drug-supplemented group, 450 mg/kg bodyand eluted with ethyl acetate/ethanol(9: 1 ). The weight of StP was given for five daysfraction 2, 3 and 4 were pooled as stP, and the frac- 1.5 Estimation of Lipid Profiletion 5, 6 and 7 were merged as drug bThe diabetic groups were fed with 600, 450 and1.2 Animals300 mg/kg of StP for two weeks respectively. TotalAdult female wistar rats( 150-180 g )were used cholesterol TC), low density lipoprotein cholesteroin the experiment. Rats were kept and maintained LDL-C)and triglyceride( tg )were examined on fiunder laboratory conditions 12 h day/dark cycle. Be- nal days for each group to study the hypolipidemic effore injection the animals were allowed to acclimatize fect. tc was determined using a commercial enzy-for four days while being maintained on regular com- matic kit based on CHOD-PAP method 41; LDL-Cmercial rat diet and water ad libitumwas estimated using a commercial enzymatic kit by1.3 Preparation of Diabetic Animal Modelpolyethene sulfuric precipitation method5]; Serumrats were treated with STz TC concentration was measured using a commercialat a dosage of 80intraperitoneal injectionenzymatic kit based on a modification of the lipase-The STz was freshly dissolved in citrate buffer glycerol phosphate oxidase method 6)(0.01 mol, pH 4. 5) and kept on ice prior to use. 1.6 Oral Glucose Tolerance TestThe injection volume was 2 mL/kg. Control rats re-Normal and STz-diabetic rats were fastedceived the buffer as placebo. On the third day after overnight water al libitum. STZ-diabetic rats wereinjection of STZ diabetes was confirmed and those divided into two groups. One group was administeredrats with blood glucose levels above 20 mmol. Lwith stP at a dose of 450 mg/kg, and the othwere selected as the diabetic animalsgiven metformin( 500 mg/kg )as a positive control1.4 Examination of the Anti-Hyperglycemic Effect 30 min later, glucose(3 g/kg )was orally adminisof the herbal fractionstered to each rat by a feeding syringe. Glucose corThe herbal fractions were screened with the anicentration was measured at o( just before the oral admal model. A total of 36 rats( 30 diabetic rats six ministration of glucose ) 30, 60, 90 and 120 min afnormal rats )were used. Diabetic rats were randomly件H中国煤化工 d and diabetic controldivided into five groups. The treatment of each group grouCNMH Gse lowas as follows1.7 Statistical Analysisgroup 1: normal untreated ratsAll the group data were statistically evaluatedgroup 2: diabetic control groupand the significance of various treatments was324DENG Yu-lin( Xp=t)et al. Anti-Hyperglycemic Activity of SHAN TANG PING an Ethanol Extract from YEW TREEcalculated using students t-test. The results were ex- compared with untreated control animals. Howeverpressed as mean +S.D. A value of p <0. 05 was Stp did not decrease the serum total cholesterolconsidered significantTab 2 Hypoglycemic effect of different doses of2 ResultsSTP on glucose levels in diabetic ratsTab. 1 illustrated the effect of tested drugs ondosage7th day14th dthe levels of fasting serum glucose. Administration of4.6±0.15.5±0.66.40.8drug a and StP led to a fall in serum glucose by36.6±6.038.4±8.335.8±8.234.65% and 47. 95% on the 5th day of the experiSTP450mg/kg28.1±2.7126.0±6.3112.9±2.1ment, respectively. On the other hand,treatmentSTP400mg/kg42.0±3.439.7±5.225.6±6.5with drug b failed to exert any statistically significantSTP300mg/kg38.9±5.027.5±2.5126.2±2,81changes in glucose concentration throughout the exSIP250mg/kg29.8±3.4121.0±2.1220.6±1.52perimental period. It was also observed that metValues were given as mean +S D. NC normal control DCformin produced significant reduction in the serumbetic control Treated groups were compared with the diabetic controlglucose levels of fasted STZ-treated diabetic ratsp<0.05;p<0.01Tab 1 Hypoglycemic effect of yew tree extractsTab 3 Effect of SIP on serum lipid profileon serum glucose in STZ-induced diabeticof normal and diabetic ratsrats( 400 mg/kg)C,Ammo L-l)(n=6)mmot L )(mmot L)(mmo L-1)(n=6)Ist d3rd day1,16±0.241.67±0,230.22±0,126,9±0,27.7±0.86.6±0,2D27±0.963.85±0.870.78±0.1741.0±4.750.1±4.2STP450mg/kg0.80±0.5923.90±0.300.32±0.13250.8±14243.4±9.233.2±3.92SIP400mg/kg0.79±0.0223.70±0.630.41±0.2032.2±2.7141.6±4.938.7±5.1STP300mg/kg1.61±0.0913.43±0.330.29±0.23STP41.5±2.4274±6.3221.6±9.32as mean tS D. NC normal control, dc dia-metformin47.4±7.940.0±7.034.3±2.22betic control Treated groups were compared with the diabetic controlValues were given as mean +S D. i NC normal control DC dip<0.01:2p<0.001betic control Treated groups were compared with the diabetic controlAs shown in fig.1 it was observed that STPp<0.05:2p<0.01450 mg/kg did not affect the serum glucose concenThe most effective dose of STP was examined. tration Csg in normal rats. After administering it toTab 2 represented the dependence of serum glucose normal rats for 14 days, there was no statistical diflevel on the StP dosage. The maximum hypo- ference between administered drug rats and normalglycemic effect(54. 1%)was obtained in the group rats(p>0.05). Tab. 4 showed the serum glucosereceived 450 mg/kg per day after two weeks of concentration of normal and diabetic rats treated withs compared to other groups. The dose of450 mg/kg was selected for further evaluation圆 normal+STPThe levels of total cholesterol triglyceride andlow density lipoprotein cholesterol in the blood were中国煤化工shown in Tab. 3. After daily administration of STpCNMHG(450 mg/kg )for two weeks, there were 75.8%re-duction in serum triglycerides( p <0.001 )andFig 1 Effect of STP( 450 mg/kg )on serum glucose47.4% reduction in serum LDL-C(p<0.01 )levelsconcentration in normal rats( P>0. 05)Journal of Beijing Institute of Technology 2005, Vol. 14, No. 3STP and metformin after oral administration of glu- decreased after 60 min administration compared withcose(3 g/kg ) In both StP and metformin treated vehicle controlgroups serum glucose concentration was found to bTab 4 Oral glucose tolerance test of STP and metformin in normal and diabetic ratsgroupCs(mmot L)(n=6)120 min5.8±0.710.2±2.09.5±2.28.7±0.97.8±1.30,6±11.048.9±10.441.5±3,236.8±1.432.1±2.726.8±2.939.7±1.027,5±4.042,0±4.027,0±2,27±5.1225,0±4.01Values were given as mean +S D. NC normal control DC diabetic control Treated groups were compared with the diabetic controlanimals. A 2-4 fold increase in serum non-esterified3 Discussiontriglyceride and low density lipoprotein cholesterolThe single high dose STz-induced diabetic rat is have been observed in STZ-induced diabetic rats. In-one of the animal models for type I or insulin-depen- terestingly in the groups given STP, the levels of TGdent diabetes. In this model, diabetes arises from ir- and LDL C are founded to near and lower tharreversible destruction of the B-islet cells of the pancre- mal respectively. The decrease in diabetic hyperlipi-ans causing degranulation or reduction of insulin se- daemia could be through its control of hyperglycaemiacretion. In this type I model of diabetes the insulin and the hydrolysis of certain lipoproteins and their seis markedly depleted 8]. Insulin one of the most ef- lective uptake and metabolism by different tissues/orfective therapeutic reagents is too expensive to be inhibition of cholesterol-esterase activation of fattyused popularly. There is a continuing effort to find acid synthase acetyl-Coa carboxylase and productioninsulin substitutes secretagogues or sensitizers from of triglycerides precursors as acetyl-Coa and glycerolsynthetic or plant sources for the treatment of dia- phosphate 10 The results indicate that STP may alsobetes. At the present study treating diabetic rats be applied to the treatment of diabetic complicationswith the extracts of yew tree shows significant anti- such as atherosclerosis myocardial infarction, neuhyperglycemic activity. The ability of STP to reverse ropathy,etcthe hyperglycemia of STz-treated rats is confirmedAs shown in Tab. 4, the glucose tolerance in diaThe maximum percent reduction in glucose levels has betic rats has improved in administration STP andbeen seen in the group receiving 450 mg/kg per day, metformin groups. The results havethatand its glucose concentration can be reduced by StP can cause a significant decrease54.1%. Since STP has no influence on blood sugar in glycemic peak during the glucose tolerance test as thenormal rats and shows anti-hyperglycemic effect in reference drug metformin did. It means that it mighseverely diabetic rats( serum glucose >25 mmot L I ), it enhance glucose utilization, restore the delayedndicates that STP may have extra-pancreatic anti- response or inhibit the intestinal absorption ohyperglycemic mechanisms of action or exert a direct glucose Il]nsulinomimetic effect. This mechanism has been ob中国煤化工 P is under the wayserved in the use of ceiba pentandra in the treatment ThenyhCN MH Ganism of their hypoof diabetes 9Jglycemic action will be established. In summaryn addition to the hypoglycemic activity of steSTP at a dose of 450 mg/kg has been shown to haveit also possesses lipid lowering properties in diabetic strong hypoglycemic and anti-hyperlipidemicDENG Yu-lin( Xp=t )et al. Anti-Hyperglycemic Activity of SHAN TANG PING an Ethanol Extract from YEW TREEproperties on diabetes rats. In addition it will be also473-480helpful in reducing the complications of lipid profile [6] McGowan M W, Artiss J D, Strandbergh DR. A peroxseen in some diabeticsidase-coupled method for the colorimetric determination ofserum triglycerides[J I Clin Chem, 1983, 29(10): 5 38References :[7] Pari L, UmaMaheswari J. Hypoglycaemic effect of musa[ 1] King h, Aubert R E, Herman WH. Global burden ofsapientum L in alloxan-induced diabetic rats[ JEthnopharmacol, 1999, 6812)321-32projection[ J ] Diabetes Care, 1998, 21(5):1414[8] Omura T, Sato R. The carbon monoxide binding pig-ment of liver microsomes, I: Evidence of its hemoprotei[2] Pari L, Umamaheswari J. Antihyperglycaemic activity ofnaturd J I. Journal of Biological Chemistry 1964, 239musa sapientum flowers: Effect on lipid per(10)2370-2378alloxan diabetic rats]. Phytother Res 2000,148): 1[9] Ldeji O, Omekarah I. Hypolycemic properties of aqueousbark extract of ceilxa pentandre in streptozotocin-induced[ 3] Youichi S, Narihiko F, Chieko U, et al. Multidrug rebetic rat J ]. Ethnopharmacol, 2003, 84( 12): 139sistant cancer cell susceptibility to cytotoxic taxane diterpenes from[10] Jouad H, Lemhadri A, Maghrani M, et al. CholesterolMedicinal Chemistry Letters, 2002, 12lowering activity of the aqueous extract of spergularia(6)2785-2788purpurea in normal and recent-onset diabetic rats[ J][4] Allain C, Poon L S. Enzymatic determination of totaEthnopharmacol 2003, 8X 6)43-49serum cholestero[J ] Clin Chem, 1974, 20(5):470[11] Bailey C j. Biguanides and non insulin dependent diabetes mellitus[J]. Diabetes Care, 1992, 156):755[ 5] Wilson E D, Spiger MJ. A dual participation method forquantitative plasma lipoprotein measurement without ulEditor: Wang Yuxiaracentrifugatior j]. Lab and Clin Med, 1973, 829)中国煤化工CNMHG