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OBJECTIVE: To explore the effects of lead exposure on inflammatory damage of hippocampus and cognitive impairment in diabetic rats. METHODS: The specific pathogen free(SPF) male healthy Wistar rats were randomly divided into control group and lead-exposed group. The SPF male Goto-Kakisaki Wistar rats rats were randomly divided into diabetes group and diabetes lead-exposed group, with 10 rats in each group. Rats in lead-exposed group and diabetes lead-exposed group were continuously exposed to lead acetate water with a mass fraction of 0.025% for 9 weeks. Rats in control group and diabetes group were given distilled water. The body weight and blood glucose level of rats were measured before lead exposure and at 1, 3, 5, 7 and 9 weeks after exposure. After the exposure, Morris water maze test was used to evaluate the learning and memory ability of rats. The lead levels in whole blood and hippocampal tissues were detected by inductively coupled plasma mass spectrometry, and the expression of mRNA and protein expression of inflammatory factors in hippocampal tissues of rats were detected by real-time fluorescence quantitative polymerase chain reaction and enzyme-linked immunoadsorption, respectively. RESULTS: At the end of lead exposure, the difference of body mass of rats in the diabetes group and the diabetes lead-exposed group was not statistically significant compared with that in the same group before exposure(all P values were >0.05); but the body mass of rats in these two groups was lower than that of the control group and the lead-exposure group(all P values were <0.05). The blood glucose levels of rats were higher in the diabetic group and the diabetes lead-exposed group than that in the control group and the lead-exposed group, respectively(all P values were <0.05). Morris water maze test showed that the escape latency of rats in the 1 st, 2 nd and 3 rd day were longer in diabetes group and the diabetes lead-exposed group than that in the control group and the lead-exposed group(all P values were <0.05). The number of times of crossing platforms were less in the lead-exposed group and the diabetes group than that of the control group(all P values were <0.05). The number of times of crossing platforms was more in the diabetes lead-exposed group than that in the other 3 groups(all P values were <0.05). The levels of lead in blood and hippocampus of rats were higher in the lead-exposed group than those in the control group(all P values were <0.05), and those in the diabetes lead-exposed group were higher than that in the other 3 groups(all P values were <0.05). The relative expression of mRNA of interferon-γ(ifn-γ) and interleukin(il)-6 in hippocampal tissues of rats was higher in the lead-exposed group and the diabetes group than that of the control group(all P values were <0.05). The relative expression of mRNA of tumour necrosis factor-α(tnf-α) and il-1β in the hippocampal tissues of rats was higher in the diabetes group than that of the control group and the lead-exposed group, respectively(all P values were <0.05). The relative expression of mRNA of ifn-γ, tnf-α, il-1β and il-6 in hippocampal tissues of rats was higher in the diabetes lead-exposed group than that of the other 3 groups(all P values were <0.05). The relative protein expression of IFN-γ, TNF-α, IL-4 and IL-6 in hippocampal tissues of rats was higher in lead-exposed group than that of the control group(all P values were <0.05). The relative protein expression of IFN-γ, TNF-α, IL-1β and IL-6 in hippocampal tissues of rats was higher in diabetes group than that of the control group(all P values were <0.05). The relative protein expression of IFN-γ, IL-1β and IL-6 in hippocampal tissues of rats was higher in diabetes group than that of the other 3 groups(all P values were <0.05). CONCLUSION: Diabetes can promote the lead accumulation in the blood and hippocampus of rats. The combined effect of lead exposure and diabetes can up-regulate the expression of pro-inflammatory cytokines in the hippocampal tissues of rats, aggravate the inflammatory response, and have a synergistic effect on the cognitive impairment in rats.
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Objective:To discuss the protective effects of extract from fermented buckwheat flower and leaf (EFBFL) on the kidney injury in the spontaneously obese type Ⅱ diabetic db/db mice,and to elucidate their possible action mechanisms from the protein expression levels of peroxisome proliferator-activated receptor γ(PPARγ) and nuclear factor-κB (NF-κB) in kidney tissue.Methods:The 8 weeks old male db/db mice were selected and the littermate db/m mice were used as normal control group;the db/db mice were randomly divided into model group,low dose of EFBFL group and high dose of EFBFL group,10 mice in each group.The mice in low and high doses of EFBFL groups were intragastrically given 50 and 100 mg · kg-1 EFBFL,and the mice in normal control group and model group were intragastrically given the equal amount of distilled water once daily for 8 weeks accordingly.The levels of fasting blood-glucose (FBG) of the mice in various groups were tested respectively before and after administration.Full automatic biochemical analyzer was used to detect the levels of serum creatinine (SCr) and blood urea nitrogen (BUN) of the mice,and the kidney index was calculated.The morphology of kidney tissue was observed by HE staining and Masson staining,and immunohistochemical method and Western blotting method were used to detect the expression levels of PPARγ and NF-κB protein in kidney tissue.Results:Compared with model group,the levels of FBG and the levels of serum SCr and BUN in EFBFL groups were significantly decreased (P＜0.05 or P＜0.01),and the kidney indexes were increased (P＜0.01).Compared with normal control group,the kidney glomerular of the mice in model group was weaked,glomerular basement membrane was diffusely thickened,the foot process was coalesced or disappeared,and the kidney tissue fibrosis was serious;compared with the model group,the above performance of the mice in EFBFL groups were improved in different degrees,especially in high dose of EFBFL group.Compared with model group,the expression levels of PPARγ in kidney tissue of the mice in EFBFL groups were increased (P＜0.01) and the expression levels of NF-κB in kidney tissue of the mice were decreased (P＜0.01).Conclusion:EFBFL can improve the kidney injury in the spontaneously obese type Ⅱ diabetic db/db mice,and its possible mechanism may be related to lowering the level of blood glucose,up-regulating the expression of PPARγ and down-regulating the expression of NF-κB in the kidney tissue of the mice.
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Aim To discuss the effectsof extract from fermented buckwheat flower and leaf(EFBFL) on myocardial injury in spontaneously obese type Ⅱ diabetic db/db mice and its mechanism.Methods 9-week-old male db/db mice were randomly divided into high level EFBFL dose group(EFBFL-H, 0.1 g·kg-1), low level EFBFL dose group(EFBFL-L, 0.05 g·kg-1),metformin hydrochloridecontrol group, model control group, and normal control group, with 10 mice in each group.All groups were treated with 8 wks of drugs by gastric perfusion.The random blood glucose(RBG) was tested respectively at the end of 2nd, 4th, 6th, and 8th wk.Finally, the levels of creatine kinase(CK) creatine kinase MB(CK-MB), andadvanced glycosylation endproducts(AGEs) were detected after 8 wks.The morphological changes of myocardium were observed under light microscope by HE staining, and the ultrastructure of myocardium was observed under electron microscope.Immunohistochemical method and Western blot were used to detect myocardial tissue glucose transporter-4(Glut-4).Results EFBFLcould repress patho-proceeding of myocardial fibrosis efficiently, and significantly decrease the level of blood glucose, CK,CK-MB, and AGEs in db/db mice.Meanwhile, it could increase the expression of Glut-4 in myocardial tissues of mice.Conclusions EFBFL can prevent myocardial injury in spontaneously obese type Ⅱ diabetic db/db mice.The possible mechanism may be related to lowering the level of blood glucose and serum AGEs and up-regulating Glut4of cardiac muscle.
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Aim To observe the effect of agiophyllum oligo saccharides ( AOS) on reducing blood sugar, im-proving insulin resistance on diadetic Goto-Kakizaki ( GK) rats, and to explore the possible mechanism. Methods The type 2 diabetes GK rats were divided into six groups: model control group ( MC ) , Glenn benzene urea group ( GLB ) , high agriophyllum squar-rosum coarse oligosaccharides ( AOS-H ) , medium ( AOS-M ) , low dose group ( AOS-L ) , homologous Wistar rats as normal control ( NC ) . All animals were administered with AOS by oral gavage, for 8 weeks. The fasting blood glucose ( FBG) , random blood sugar ( RBG) , glucose tolerance ( OGTT) were tested before and after administration. No fasting sugar load status before and after dosing changes in blood glucose and serum insulin level in rats were measured in the previ-ous 8 weeks. At the end of administration, the fasting serum glucose ( FPG) , insulin ( FINS) , OGTT and in-sulin resistance index ( HOMA IR) in fasting rats were analyzed. Lastly, the pathological changing of pancreas was observed by HE staining. Results The blood glucose of fasting GK rats was not influenced after using AOS. However, the random blood glucose significantly reduced, the glucose tolerance was improved and AUC was obviously reduced (P < 0. 01) after using AOS. The best effect was on AOS-M group, which was similar with Glenn benzene urea. Through our research, we found AOS could promote release of insulin. This best effect was on AOS-M and AOS-L groups, and the time and quantity of release were better than Glenn benzene urea. Finally, AOS inhibited the pathological changes of islet tissue on GK rats, increased the quantity of pancreas and islet cells. Compared with model group, the changing of islet structure was significantly reduced in AOS group. Conclusion AOS could obviously improve insulin resistance and lower blood sugar, and the mechanism of this effect may be related with rapidly promoting insulin release, increasing the islet cell proliferation,and improving the function of islet.
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n-Octanol/ water partition coefficients (Kow ) is an important parameter commonly used to explain toxicity, activity and transmembrane of drugs. However, it is difficult to be detected by direct experimental determination. In this work, a set of 29 neutral and acidic analogues of naphthalene and anthraquinone with reliable experimental Kow data was chosen as model compounds for establishing linear relationship between the logarithm of apparent n-octanol/ water partition coefficient (lgKow), and the logarithm of reversed phase-high performance liquid chromatography (RP-HPLC) retention factor of the solutes corresponding to neat aqueous fraction of mobile phase (lgkw ) as the quantitative structure-retention relationship (QSRR) model. Methanol-water mixture was used as mobile phase at various pH, and retention time (tR ) was rectified by a dual-point retention time correction (DP-RTC) in this method. The experiment results indicated that the proposed QSRR model had good correlation coefficient R2 = 0. 974 -0. 976 with satisfactory results of internal and external validation (the cross-validated correlation coefficient R2cv of 0. 970-0. 973, and 1. 4% ≤relative error (RE)≤7. 9% for all the 6 verification compounds). In addition, this QSRR model was compared with linear solvation energy relationship ( LSER) involved in different descriptors of molecular structure, showing no differences. The QSRR model was applied to measure Kow of 11 naphthalenes and anthraquinones, and the predicted data were compared with Shake-flask method (SFM) experimental ones, as well as calculated ones obtained by software. The results suggested that the proposed method for Kow determination in this work was more accurate, simple and fast. To the best of our knowledge, this is the first report on measuring Kow data for these compounds. The proposed strategy provides the possibility in determining Kow of lipophilic components in complex mixture more quickly and accurately by RP-HPLC.
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This study was aimed to observe the antibacterial activity and bactericidal action ofC.albicans in vitro, and the effects of curing monilial vaginitis mouse by extraction of globeflower residue fermentation (EGRF) in vivo.In vitrostudy, test tube method as well as plate method were used to determine the minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) ofC.albicansrespectively.In vivo, mouse were devided into normal controlled group,C. albicans vaginitis model group (Model), Model + EGRF (40, 80, 160 mg?kg-1) group, and fluconazole group (20 mg?kg-1). All drugs were vaginal delivery once a day with continuous administration for seven days. Then vulva inflammation, negative rate of vaginal discharge, microbial load of vaginal lavage and the pathological changes of vaginal mucosa were observed. After the treatment of EGRF, the MIC and MBC of Candida albicans were 0.31 mg?mL-1 and 1.25 mg?mL-1, respectively, while the potency unit ratios between EGRF and fluconazole of MIC and MBC were 2 to 1 and 1 to 1, respectively. In comparison with Model, vulva inflammation of Model + EGRF gourp and fluconazole group was improved, whileC. albicanscount in vaginal secretions of these two groups were decreased, the overcast rate ofC. albicansof vaginal douche was increased, and pathological changes of vaginal mucosa were also improved in the two groups, which were in dose-dependent manners. And high dose Model + EGRF group was close to fluconazole group. In conclusion, EGRF had obvious inhibitory effect onC. albicans in vitro. It also had a better therapeutic effect onC. albicans vaginitis mouse.
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Objective To investigate the therapeutic effects and mechanism of Artemisia argyi ferment substance on systemic Candida albicans infection. Methods The model of systemic Candida albicans infection was established in immunosuppressed mice. The model mice were randomly divided into the model control,Artemisia argyi ferment substance( AAFS) at different doses(100,200,and 400 mg·kg-1 )and fluconazole group(20 mg·kg-1 ),30 mice in each. Mice in each treatment group were given therapeutic drugs by gavage for 5 consecutive days,twice daily. The survival of mice was determined 21 days after the model was set up. The serum levels of IFN-γand IL-2 were determined by ELISA. The proliferation activity of T lymphocyte in the spleen was detected by MTT assay. The number of living fungi in liver and kidney tissues was counted. Results Compared with the model control,AAFS at middle and high doses and fluconazole significantly increased the survival rate of mice,the serum levels of IFN-γand IL-2,and the proliferation activity of T lymphocyte in the spleen,but decreased the number of living fungi in tissues(P〈0. 01). Compared with low dose AAFS,middle and high doses of AAFS and fluconazole showed significantly different effect on each index(P〈0. 05 or P〈0. 01),but there was no difference among these groups(P〉0. 05). Conclusion AAFS at 200-400 mg·kg-1 has inhibitory effects on systemic Candida albicans infection in mice,the mechanism of which is related to increasing the proliferation of T lymphocyte in spleen and the levels of IFN-γand IL-2 in serum.
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<p><b>OBJECTIVE</b>To explore the effect and mechanism of flavones of buckwheat flower and leaf (FBFL) on lowering blood glucose and improving insulin resistance in type 2 diabetic rats.</p><p><b>METHOD</b>Seventy healthy male Wistar rats were used in this trial. Ten of them were selected randomly as normal group; the others were given fat milk by intragastric administration daily, from the 14th day on, low dose tetraoxypyrimidine was added by intraperitoneal injection every other day for three times. Rats with fasting (72 hours after the last injection) blood sugar > or = 16.7 mmol x L(-1) and K(IPT) < 60% of normal group were selected as type 2 diabetic model with insulin resistance, which were randomly divided into 5 groups: model group. LGLT group; low, moderate and high dosage FBFL groups (L-FBFL; M-FBFL; H-FBFL). Every rat was treated accordingly for 4 weeks; then FBG, FFA, INS were detected and ISI was calculated to evaluate the degree of insulin resistance. Liver PTP1B expression was determined by immunohistochemistry method. staining were observed by light microscopy.</p><p><b>RESULT</b>FBFL could dose-dependently inhibit the rising of FBG, FFA, INS, improve the state of insulin resistance and reduce the expression level of liver PTP1B.</p><p><b>CONCLUSION</b>FBFL could effectively improve insulin resistance in type 2 diabetic rats induced by tetraoxypyrimidine and fat milk and showed dose-dependence relationship.</p>
Subject(s)
Animals , Humans , Male , Rats , Diabetes Mellitus, Type 2 , Drug Therapy , Genetics , Metabolism , Disease Models, Animal , Fagopyrum , Chemistry , Flavones , Flowers , Chemistry , Gene Expression , Insulin Resistance , Liver , Metabolism , Plant Extracts , Plant Leaves , Chemistry , Protein Tyrosine Phosphatase, Non-Receptor Type 1 , Genetics , Metabolism , Random Allocation , Rats, WistarABSTRACT
BACKGROUND: Non-enzymatic glycation of proteins is involved in the complications of diabetes mellitus. Previous experiments have demonstrated that total flavones of buckwheat flower (TFBF) could improve carbohydrate tolerance. However, it is little known whether TFBF inhibit the non-enzymatic glycation of proteins.OBJECTIVE: To investigate the influences of TFBF on the non-enzymatic advanced glycation end products (AGEs) of proteins in vivo and in vitro.DESIGN: Completely randomized controlled trial.SETTING: Department of Pharmacology, North China Coal Medical College.MATERIALS: Totally 75 adult SD rats , of clean grade, weighing (200±20) g, including 38 female rats and 37 male rats, were provided by the institute of experimental animals, Chinese Academy of Medical Sciences (Certification No. SCXK11-00-0006). TFBF was extracted by our laboratory from flowers of buckwheat. The blood glucose kit was purchased from Beijing Biosino Biotechnology Company Ltd. Penicillin (Batch No.031020, 8×105 U) and streptomycin (Batch No. 030920, 1×106 U) were purchased from North China Pharmaceutical Company. Streptozotocin and BSA were purchased from Sigma Company. Fructosamine kit was purchased from Nanjing Jiancheng Bioengineering Institute, and the other chemicals were analytical pure produced domestically.METHODS: This experiment was carried out in the Department of Pharmacology, North China Coal Medical College from March to October 2004.In the first experiment, in vivo macromolecular AGEs was measured: ①Modeling and grouping: Rats were divided into 3 groups according to body mass: Normal control group (n=15), the rats were treated with 8 mL/kg normal saline intraperitoneally. Streptozotocin-treated group (n=45), the rats were fasted for 16 hours and then treated with 80 mg/kg streptozotocin of 8 mL/kg intraperitoneally. Twenty-two hours later, the blood of all rats was harvested from vena caudalis to measure the level of blood sugar.Those with fasting blood glucose ≥ 15 mmol/L were acted as diabetic rats.Streptozotocin-treated group were divided into 3 subgroups, 15 rats in each subgroups. Each rat was given intragastric administration of 0.1, 0.2 and 0.4 g/kg TFBF. Model group (n=1S): Rats were only treated with 80 mg/kg streptozotocin of 8 mL/kg . The rats in normal control group and model group were given the same volume of salt water. The administration was once a day for 12 weeks successively. ②Measurement of fasting blood glucose: After the last administration, the rats of streptozotocin-treated group were fasted for 12 hours and the blood was harvested from vena caudalis. The fasting blood glucose was measured by glucose oxidase method. ③The levels of blood plasma and nephridial tissue fructosamine and macromolecular AGEs were measured: The rats of each group were anesthetized with ethyl ether on the second day following the last administration. Blood was chosen from carotid artery, and plasma was separated.Kidneys were taken at the same time, prepared into 100 g/L tissue homogenate and centrifuged at low temperature. The levels of fructosamine in plasma and the supernatant fluid of kidney homogenate were measured according to the instructions of the kit. AGEs in plasma and renal tissue were determined by fluorospectrophotometer. The products of macromolecular AGEs were calculated. In the second experiment, in vitro macromolecular AGEs were measured as below: 0.01, 0.05, 0.10 mg/L TFBF of 6 mLrespectively was prepared with solution A (0.2 mol/L glucose, 2×l06 U/Lpenicillin, 2×106 U/L streptomycin , PBS containing 20 g/L bovine serum albumin). Control groups were set: ① without TFBF, ② without TFBF and glucose, ③ without BSA, ④ without glucose. Five parallels of each sample were sterilized by filtration and incubated in the attemperator at 37 ℃. The fluorescence of AGEs (F) in the culture was determined at the 4th, 8th and 12th weeks. Inhibition ratio (IR) was calculated and the inhibition of TFBF on AGEs was observed.MAIN OUTCOME MEASURES: In the first experiment, the levels of fasting blood glucose, fructosamine in kidney and plasma, and AGEs were measured. In the second experiment, the inhibition of TFBF on AGEs in vitro was measured.RESULTS: In the first experiment, 75 rats were involved, and 56 successful rats entered the stage of result analysis. The levels of blood glucose,fructosamine in kidney and plasma of rats in the model group were significantly higher than those of rats in the normal control group (t=7.572,10.186, 5.794,P ＜ 0.01 ). The level of blood glucose of rats in the 3 subgroups was significantly lower than that of rats in the model group (t=3.357,4.382,3.938,P ＜ 0.05-0.01); The levels of fructosamine in kidney and plasma of rats in the 0.2 and 0.4 g/kg TFBF groups were significantly lower than those in the model group (t=5.109, 4.605, 3.731,3.097,P ＜ 0.05-0.01 ). The levels of AGEs in plasma and kidney of rats in the model group were significantly higher than those in the normal control group (t=6.463, 12.704,P ＜ 0.01 ), while the levels of AGEs in plasma of rats in the streptozotocin-treated group were similar to those in the model control group (P ＞. 0.05), and those in kidney of rats in the streptozotocintreated subgroups were significantly lower than those in the model group (t=9.845, 12.799, 12.899,P ＜ 0.01 ). In the second experiment, the level of macromolecular AGEs of each group was gradually increased with ime.TFBFcould inhibit the formation of macromolecular AGEs in dose- and time-dependent manner.CONCLUSION: TFBF obviously inhibited the formation of AGEs of proteins in vivo and in vitro.
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Objective:To observe the inhibitory effect on ?-glucosidase of 10 kinds Chinese herbs and to screen the Chinese herbal medicines which have great inhibitory effect on ?-glycosidase.Methods:The ?-glucosidase was extracted from small intestine of rat.The amount of glucose was measured with produced from substrate of malt sugar.The inhibitory effect of 10 kinds of Chinese herbs on ?-glucosidase was observed by this enzyme reaction system.Then disposable gastric perfused malt sugar(2 g/kg) and the extraction screened at the same time,detected the levels of blood glucose after 60 min.The positive control group is acarbose(ACAR) group.Results:The three kinds Chinese herbs(Chishao,Shanzhuyu and Sangbaipi) showed very good inhibitory activities,and they showed obviously concentration-effect curve relationship.Among them,the inhibitary activity of Sangbaipi is stronger than Chishao and Shanzhuyu.While the dose of Sangbaipi reached 10mg/mL,the inhibition rate arrived 80%,which effect was equivalet to the dose of 1mg/ml acarbose.The results of postprandial blood glucose in vitro showed us:Sangbaipi,Chishao and Shanzhuyu can inhibit postprandial blood glucose levels in rats that have been disposable gastric perfused malt sugar after 60min(P0.05).Conclusion:The three kinds of Chinese herbs(Chishao,Shanzhuyu and Sangbaipi) can inhibit ?-glucosidase activity obviously in both vitro and vivo.
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Aim To explore the vasodilative effect on rat thoracic aortic ring of total flavonoids of Buckwheat flowers and leaves(TFBFL) and the underlying mechanisms.Methods Isometric tension measurements were used to study the effect of TFBFL on isolated rat thoracic aorta rings.Laser scanning confocal microscope was employed to measure the concentration of intracellular free calciums.Results In aorta rings precontracted with phenylephrine or potassium chloride,TFBFL caused a dose-dependent relaxation in both endothelium-intact and denuded rings and the relaxant effect of TFBFL was more potent on endothelium-intact aorta rings than that on endotheliumdenuded aorta rings(P
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Aim To investigate the influence of total fl avones of buckwheat flower (TFBF) on the productivity of the non-enzymatic advanced glycation end products (AGEs) in vivoand vitro. Methods TFBF in different dosages (0.1 g?kg -1?d -1,0.2 g?kg -1?d -1,0.4 g?kg -1?d -1) was taken orally by streptozotocin-induced diabetic rats for 12 wk. After the treatment, blood glucose, fructosamine and AGEs in plasma and kidney were measured. Meanwhile, glucose and bovine serum albumin (BSA) were incubated with TFBF at different concentrations (0.01 mg?L -1,0.05 mg?L -1,0.10 mg?L -1) respectively for 4,8,12 wk.The fluorescence intensity of glycated BSA was detected by a spectrophotometer BSA was detected spectrophotometer.Results TFBF significantly lowered the level of blood glucose in diabetic rats (P