Antidiabetic effect of a leaf extract from Gymnema sylvestre in non-insulin-dependent diabetes mellitus patients

The effectiveness of GS₄, an extract from the leaves of Gymnema sylvestre, in controlling hyperglycaemia was investigated in 22 Type 2 diabetic patients on conventional oral anti-hyperglycaemic agents. GS₄ (400 mg/day) was administered for 18–20 months as a supplement to the conventional oral drugs. During GS₄ supplementation, the patients showed a significant reduction in blood glucose, glycosylated haemoglobin and glycosylated plasma proteins, and conventional drug dosage could be decreased. Five of the 22 diabetic patients were able to discontinue their conventional drug and maintain their blood glucose homeostasis with GS₄ alone. These data suggest that the beta cells may be regenerated/repaired in Type 2 diabetic patients on GS₄ supplementation. This is supported by the appearance of raised insulin levels in the serum of patients after GS₄ supplementation.     

Use of Gymnema sylvestre leaf extract in the control of blood glucose in insulin-dependent diabetes mellitus

GS₄, a water-soluble extract of the leaves of Gymnema sylvestre, was administered (400 mg/day) to 27 patients with insulin-dependent diabetes mellitus (IDDM) on insulin therapy. Insulin requirements came down together with fasting blood glucose and glycosylated haemoglobin (HbAlc) and glycosylated plasma protein levels. While serum lipids returned to near normal levels with GS₄ therapy, glycosylated haemoglobin and glycosylated plasma protein levels remained higher than controls. IDDM patients on insulin therapy only showed no significant reduction in serum lipids, HbAlc or glycosylated plasma proteins when followed up after 10–12 months. GS₄ therapy appears to enhance endogenous insulin, possibly by regeneration/ revitalisation of the residual beta cells in insulin-dependent diabetes mellitus.     

Effect of D-400, an Ayurvedic Herbal Formulation on Experimentally Induced Diabetes Mellitus

In the present study, after D-400 treatment a significant reduction in blood sugar levels in alloxan induced diabetes was observed, an oral glucose tolerance test (OGTT) showed a significant lowering of AUC in streptozotocin induced diabetes in rats. There was a rise in hepatic glycogen level closer to normal after D-400 treatment. In the pancreas of diabetic rats, D-400 therapy showed a significant increase in islet number and beta cell count and appeared to bring about blood glucose homeostasis by increasing insulin secretion through repair/regeneration of endocrine pancreas which may be responsible for the prevention of hepatic glycogenolysis.     

Effect of Sclerocarya birrea (Anacardiaceae) stem bark methylene chloride/methanol extract on streptozotocin-diabetic rats

Sclerocarya birrea (Anacardiaceae) is used as a traditional treatment of diabetes in Cameroon. In this study, we investigated the possible antidiabetic effect of the stem bark extract in diabetic rats. Diabetes was induced by intravenous injection of streptozotocin (STZ, 55 mg/kg) to male Wistar rats. Experimental animals (six per group), were treated by oral administration of plant extract (150 and 300 mg/kg body weight) and metformin (500 mg/kg; reference drug) for comparison, during 21 days. The stem bark methanol/methylene chloride extract of Sclerocarya birrea exhibited at termination, a significant reduction in blood glucose and increased plasma insulin levels in diabetic rats. The extract also prevented body weight loss in diabetic rats. The effective dose of the plant extract (300 mg/kg) tended to reduce plasma cholesterol, triglyceride and urea levels toward the normal levels. Four days after diabetes induction, an oral glucose tolerance test (OGTT) was also performed in experimental diabetic rats. The results showed a significant improvement in glucose tolerance in rats treated with Sclerocarya birrea extract. Metformin, a known antidiabetic drug (500 mg/kg), significantly decreased the integrated area under the glucose curve. These data indicate that Sclerocarya birrea treatment may improve glucose homeostasis in STZ-induced diabetes which could be associated with stimulation of insulin secretion.     

Effect on glycemia in rats with type 2 diabetes induced by streptozotocin: low-frequency electro-pulse needling stimulated Weiwanxiashu(EX-B 3) and Zusanli(ST 36)

OBJECTIVE: To investigate the effect of low frequency electro-pulse acupuncture(EA) on blood glucose in rats with streptozotocin-induced type 2diabetes, and the possible mechanism underlying the action.METHODS: Rat models were established with high fat feeding and intraperitoneal injection of streptozotocin(STZ)(30 mg/kg). Rats with a random blood glucose 16.7 mmol/L and blood glucose at 2 h-point of oral glucose tolerance test(OGTT) 11.1 mmol/L were included as diabetic rats, and randomly divided into model group, EA Weiwanxiashu(EX-B 3) group, EA Zusanli(ST 36)group, glimepiride group, and EA non-acupoint group(n = 12). EA(2 Hz continuous wave, 2 m A,20 min/day, 6 days/week, 4 weeks) and intra-gastric administration of glimepiride were applied as interventions. With fasting blood glucose and OGTT tested at the end of the intervention, thestudy observed the patterns of hypoglycemic effects. For mechanism study, it observes hematoxylin and eosin staining and Masson staining of pancreas paraffin sections, protein expression of glucagon-like peptide 1 receptor(GLP-1R) in the pancreas and skeletal muscle, glucose transporter 4(GLUT4) protein expression in skeletal muscle membrane, to detect whether EA controls blood glucose via regulation of GLP-1R.RESULTS: EA Weiwanxiashu(EX-B 3) significantly increased model rats' pancreas GLP-1R, and GLUT4 of skeletal muscle membrane; the therapy significantly decreased model rats' skeletal muscle GLP-1R, restored pancreas morphology, and reduced fasting blood glucose and insulin resistance indices.CONCLUSION: EA Weiwanxiashu(EX-B 3) alone has significant effect on glycemia. EA Weiwanxiashu(EX-B 3) plus glimepiride further strengthen the effect. The regulation of the GLP-1R in pancreas and skeletal muscle might be mechanism underpinning the effect.     

Antidiabetic activity of Paspalum scrobiculatum Linn. in alloxan induced diabetic rats

Ethnopharmacological relevance

Paspalum scrobiculatum Linn. (Poaceae) is traditionally used to treat diabetes mellitus. The grains of Paspalum scrobiculatum are having potential in the development of drug for diabetes due to their antidiabetic activity.

Aim of the study

To evaluate the antidiabetic activity of aqueous and ethanolic extracts of grains of Paspalum scrobiculatum Linn. (Poaceae) in alloxan induced diabetic rats.

Materials and methods

Aqueous and ethanolic extracts (250 and 500 mg/kg body weight), were administered orally to male Wistar albino rats. Alloxan monohydrate was used to induce diabetes mellitus. Total phenolic content was estimated in the extracts. The parameters studied included oral glucose tolerance test, fasting blood glucose, serum insulin and glycated haemoglobin levels, liver glycogen content, serum lipid profile, and changes in body weights.

Results

In oral glucose tolerance test, reduction of fasting blood glucose levels took place from 60 min of extract administration. The extracts produced a dose-dependent fall in fasting blood glucose (FBG). After 15 days of treatment with extracts the maximum reduction in FBG (35.14%) was observed in diabetic rats treated with ethanolic extract 500 mg/kg dose. A significant increase in serum insulin level was observed in the treated rats. Serum lipid levels were reversed towards near normal and a control in the loss of body weight was observed in treated rats as compared to diabetic control. The extract treatment also showed a significant increase in the liver glycogen and a significant decrease in glycated haemoglobin levels. The results demonstrate that Paspalum scrobiculatum possesses significant antidiabetic activity in diabetic rats.

Conclusion

The results suggest that Paspalum scrobiculatum has antidiabetic activity, thereby justifying its traditional claim and augmenting it into the present day systems of medicine.     

Study of hypoglycaemic and hypolipidemic effects of Inula viscosa L. aqueous extract in normal and diabetic rats

The present study was designed to examine the hypoglycaemic and hypolipidemic activity of Inula viscsa aqueous extract on normal and diabetic rats. In normal rats, a significant reduction in blood glucose levels 2 h was observed after a single oral administration (p<0.001). Repeated daily oral administration significantly reduced blood glucose levels after 4 days of treatment (p<0.01). In diabetic rats, a significant reduction in blood glucose levels was observed 1 h after a single oral administration (p<0.001). Repeated oral administration reduced blood glucose levels at the 4th day (p<0.001). No change in total plasma cholesterol and triglyceride levels was observed after both a single and repeated oral administration in both normal and diabetic rats. In addition, plasma insulin levels and body weight remained unchanged after 15 days of repeated oral administration in normal and diabetic rats. We conclude that Inula viscosa possess a hypoglycaemic but not hypolipidemic activity in normal and diabetic rats. The observed hypoglycaemic activity seems to be independent of insulin secretion.     

透穴埋线对2型糖尿病大鼠血脂、糖化血红蛋白及血清C肽的影响

目的:观察穴位埋线对2型糖尿病大鼠血糖(fasting blood glucose,FBG)、糖化血红蛋白(hemoglobin A 1c,HbA 1c)、甘油三脂(triglyceride,TG)、总胆固醇(total cholesterol,TC)、血清胰岛素(fasting insulin,FINS)、血清C肽(fasting C-peptide,FC-p)、胰岛素敏感指数(insulin sensitive index,ISI)的影响,探讨透穴埋线治疗2型糖尿病的作用机制。方法:将SD大鼠随机分为正常组、模型组和治疗组,每组10只。采用高脂饮食和腹腔注射链脲佐菌素的方法复制2型糖尿病模型。治疗组采用透穴埋线"中脘"透"下脘"、"胰俞"透"肝俞"、"脾俞"透"胃俞","关元"透"中极"、"肺俞"透"厥阴俞"、"肾俞"透"气海俞",20d治疗1次,共2次。葡萄糖氧化酶法检测FBG,酶联免疫分析法检测HbA 1c,酶分析法检测TG、TC、FINS,化学发光法检测FC-p,计算ISI及胰腺组织病理切片观察。结果:造模后,模型组FBG、HbA 1c、TG、TC、FINS、FC-p均较正常组明显升高(P0.05),ISI较正常组明显降低(P0.05)。治疗后治疗组FBG、HbA 1c、TG、TC、FINS、FC-p均较模型组明显降低(P0.05),ISI较模型组明显升高(P0.05)。胰腺组织病理切片结果显示,模型组胰岛内细胞核变形,细胞水肿,胞间隙增宽有纤维增生,治疗组胰腺组织结构与正常组接近。结论:透穴埋线治疗可使2型糖尿病大鼠血糖下降、减轻胰岛素抵抗,从而起到改善脂质代谢、保护胰岛、防止胰岛细胞衰竭的作用。     

Chromium-containing traditional Chinese medicine,Tianmai Xiaoke Tablet improves blood glucose through activating insulin-signaling pathway and inhibiting PTP1B and PCK2 in diabetic rats

OBJECTIVE: Chromium is an essential mineral that is thought to be necessary for normal glucose homeostasis.Numerous studies give evidence that chromium picolinate can modulate blood glucose and insulin resistance.The main ingredient of Tianmai Xiaoke(TMXK) Tablet is chromium picolinate.In China, TMXK Tablet is used to treat type 2 diabetes.This study investigated the effect of TMXK on glucose metabolism in diabetic rats to explore possible underlying molecular mechanisms for its action.METHODS: Diabetes was induced in rats by feeding a high-fat diet and subcutaneously injection with a single dose of streptozotocin(50 mg/kg, tail vein).One week after streptozotocin-injection, model rats were divided into diabetic group, low dose of TMXK group and high dose of TMXK group.Eight normal rats were used as normal control.After 8 weeks of treatment, skeletal muscle was obtained and was analyzed using Roche NimbleGen mRNA array and quantitative polymerase chain reaction(qPCR).Fasting blood glucose, oral glucose tolerance test and homeostasis model assessment of insulin resistance(HOMA-IR) index were also measured.RESULTS: The authors found that the administration of TMXK Tablet can reduce the fasting blood glucose and fasting insulin level and HOMA-IR index.The authors also found that 2 223 genes from skeletal muscle of the high-dose TMXK group had significant changes in expression(1 752 increased, 471 decreased).Based on Kyoto encyclopedia of genes and genomes pathway analysis, the most three significant pathways were "insulin signaling pathway", "glycolysis/gluconeogenesis" and "citrate cycle(TCA)".qPCR showed that relative levels of forkhead box O3(FoxO3), phosphoenolpyruvate carboxykinase 2(Pck2), and protein tyrosine phosphatase 1B(Ptp1b) were signifi cantly decreased in the high-dose TMXK group, while v-akt murine thymoma viral oncogene homolog 1(Akt1) and insulin receptor substrate 2(Irs2) were increased.CONCLUSION: Our data show that TMXK Tablet reduces fasting glucose level and improves insulin resistance in diabetic rats.The mechanism may be linked to the inactivation of PTP1B and PCK enzymes, or through intracellular pathways, such as the insulin signaling pathway.     

Effect of Salvia officinalis L. leaves on serum glucose and insulin in healthy and streptozotocin-induced diabetic rats

The leaves of sage (Salvia officinalis L., Lamiaceae) are reported to have a wide range of biological activities, such as anti-bacterial, fungistatic, virustatic, astringent, eupeptic and anti-hydrotic effects. To determine the hypoglycaemic effect of sage leaves, we investigated the effects of essential oil and methanolic effect of the plant on healthy and streptozotocin-induced diabetic rats. The animals were made diabetic using by streptozotocin (70 mg/kg, i.p.). The methanolic extract (100, 250, 400 and 500 mg/kg) and essential oil (0.042, 0.125, 0.2 and 0.4 ml/kg) were injected intraperitoneally. The control groups were administered water and sunflower oil as vehicles of methanolic extract and essential oil, respectively. Blood samples were obtained from retro-orbital sinus before administration and 1, 3 and 5 h after administrations. The serum glucose was measured by the enzymatic method of glucose oxidase. The results showed that the essential oil of sage did not change serum glucose, while the plant extract significantly decreased serum glucose in diabetic rats in 3 h without effect on insulin releasing from the pancreas but not in healthy rats. Also, the LD₅₀ of the methanolic extract is measured (4000 mg/kg, i.p.). The present data indicate that sage extract has hypoglycaemic effect on diabetic animals and the plant should be considered in future therapeutic researches.     

The basis for the antihyperglycemic activity of Indigofera arrecta in the rat

The basis for the antihyperglycaemic property of Indigofera arrecta, a plant used for the treatment of diabetes, was evaluated using normoglycemic and streptozotocin-induced diabetic rats. The rats were given different doses of the freeze-dried extract of the plant material orally and intraperitoneally. The extract decreased the plasma glucose levels of fasting normoglycemic rats, but did not prevent the rise in plasma glucose after an oral glucose load in these rats. The extract increased plasma insulin levels. In the diabetic rats, the rise in blood glucose after an oral glucose load was not affected when the extract was administered 17 days after induction of diabetes. When administered 7 days after induction of diabetes, the rise in blood glucose was decreased, and was stabilized after 30 min. The results indicate that I. arrecta is insulinotropic, requiring functional beta cells to express its effect.     

藏药复方TKF对自发性2型糖尿病小鼠(KK-Ay小鼠)糖代谢的作用研究

目的:研究藏药复方TKF对KK-Ay小鼠的降糖作用。方法:以C57BL/6 J小鼠作为对照组,KK-Ay小鼠随机分为模型组、TKF组(1.125、2.25、4.5g/kg)和格列本脲组5组,连续灌胃35天,检测小鼠体重、空腹血糖、口服糖耐量、血清胰岛素和血脂等指标。结果:TKF 2.25g/kg组从给药7天起即出现空腹血糖的降低,并在给药期间维持在一较低水平,给药35天时TKF各组血清胰岛素水平显著降低,2.25g/kg组血清甘油三酯亦明显降低。结论:TKF具有降低KK-Ay小鼠血糖、血脂和胰岛素水平,改善胰岛素抵抗的作用。     

《金匮》肾气丸合二甲双胍对实验性2型糖尿病胰岛素抵抗大鼠血糖血脂影响的研究

目的观察《金匮》肾气丸对2型糖尿病胰岛素抵抗大鼠血糖及血脂的影响。方法选用40只SD大鼠,随机分为两组,正常对照组8只和模型组32只。正常对照组大鼠予以普通基础饲料,模型组大鼠予以高脂高糖饲料,30d后小剂量链脲佐菌素50mg／kg腹腔注射诱导2型糖尿病胰岛素抵抗大鼠,造模成功后13d,模型组大鼠随机分为糖尿病模型组、肾气丸组、二甲双胍组及肾气丸合二甲双胍组。各治疗组大鼠开始分别连续灌胃,正常对照组和糖尿病模型组等体积蒸馏水灌胃。30d后禁食12h,尾静脉采血检测血糖、血脂等生化指标。结果与正常对照组比较,糖尿病模型组空腹血糖、BUN、CH01、TG和LDL—C水平均明显增高（P〈0．001）,HDL—C水平则降低（P〈0．001）;肾气丸组、二甲双胍组及肾气丸合二甲双胍组均能降低模型大鼠空腹血糖、BUN、CHOL、TG和LDL—C水平（P〈0．05或P〈0．01）;二甲双胍组则既可降低TG和LDL—C,又可提高血清HDL-C含量（P〈0．05）。结论《金匮》肾气丸合二甲双胍可显著改善2型糖尿病胰岛素抵抗大鼠的血糖及血脂水平。     

蛇菰乙醇提取物降血糖作用的实验研究

目的：探讨蛇菰95%乙醇提取物(SHG)的降血糖作用及其机制。方法：以四氧嘧啶诱导雄性ICR小鼠形成糖尿病模型。用葡萄糖氧化酶法测定血糖浓度,用同位素放射免疫法测定血清胰岛素浓度。给动物口服SHG相当于生药20,30 g·kg^-1体重连续7～10 d,以动物不禁食和禁食2.5 h的血糖水平和口服葡萄糖负荷后的血糖水平,观察SHG对机体血糖及糖耐量的影响；以腹腔注射葡萄糖负荷后的血糖和血胰岛素水平,评价SHG对机体高血糖诱导血胰岛素水平的影响；以口服蔗糖耐量和口服淀粉耐量评价药物对糖吸收的影响。结果：SHG可显著降低正常和糖尿病小鼠的餐后血糖和空腹血糖水平。动物口服蔗糖和口服淀粉耐量实验中,SHG可明显降低并后移蔗糖或淀粉负荷后的血糖峰值,减少血糖-时间曲线下面积(AUC)。动物口服葡萄糖耐量实验中,SHG可显著降低葡萄糖负荷后血糖的峰值,减少AUC。在正常小鼠腹腔注射葡萄糖耐量实验中,SHG组平均血糖上升百分数明显低于对照组,但血胰岛素水平与对照组无明显差异。结论：SHG显著降低正常和糖尿病小鼠的餐后血糖和空腹血糖、改善葡萄糖耐量。SHG控制血糖作用的机制可能与抑制肠道α-葡萄糖苷酶和增强体内葡萄糖代谢有关。     

经络舒胶囊对糖尿病大鼠血糖及糖化血红蛋白含量水平的影响

目的:观察经络舒胶囊对糖尿病大鼠血糖、糖化血红蛋白含量水平的影响。方法:Wistar大鼠腹腔注射链脲佐菌素(STZ)制成糖尿病大鼠模型。将动物随机分为正常对照组、模型对照组、西药阳性对照组(胰岛素)、中药阳性对照组(糖脉康)、经络舒胶囊高、中、低剂量组。给药60d以后测定大鼠空腹血糖浓度及糖化血红蛋白含量。结果:与模型对照组比较,胰岛素对照组能明显降低糖尿病大鼠空腹血糖水平(P<0.01)。与模型对照组比较,胰岛素对照组和高剂量组能明显降低糖尿病大鼠糖化血红蛋白水平(P<0.05)。结论:高剂量组的经络舒胶囊能明显降低糖尿病大鼠糖化血红蛋白水平,为该制剂临床上用于糖尿病神经病变包括外周神经炎和糖尿病植物神经功能紊乱提供了实验理论依据。     

翻白草水提取物对自发2型糖尿病db/db小鼠降糖作用的研究

目的 观察翻白草水提取物对2型糖尿病db/db小鼠空腹血糖、血清胰岛素及胰岛素敏感指数的影响.方法 采用公认的自发2型糖尿病模型db/db小鼠,随机分为4组:翻白草高剂量组(400 mg·kg-1·bw-1)、翻白草低剂量组(200 mg·kg-1·bw-1)、吡格列酮组(4.05 mg·kg-1·bw-1)及模型组,...     

Anti-hyperglycaemic activity of the aqueous extract of Origanum vulgare growing wild in Tafilalet region

The effect of an aqueous extract of Origanum vulgare (OV) leaves on blood glucose levels was investigated in normal and streptozotocin (STZ) diabetic rats. In normal rats, the blood glucose levels were slightly decreased 6 h after a single oral administration (P<0.05) as well as 15 days after once daily repeated oral administration of aqueous OV extract (P<0.05) (20 mg/kg). After a single dose or 15 daily doses, oral administration of the aqueous extract (20 mg/kg) produced a significant decrease on blood glucose levels in STZ diabetic rats (P<0.001). In STZ rats, the blood glucose levels were normalised from the fourth day after daily repeated oral administration of aqueous OV extract (20 mg/kg) (P<0.001). However, this effect was less pronounced 2 weeks after daily repeated oral administration of OV extract. In addition, no changes were observed in basal plasma insulin concentrations after treatment in either normal or STZ diabetic rats indicating that the aqueous OV extract acted without changing insulin secretion. We conclude that an aqueous extract of OV exhibits an anti-hyperglycaemic activity in STZ rats without affecting basal plasma insulin concentrations.     

Effect of the desert plant Retama raetam on glycaemia in normal and streptozotocin-induced diabetic rats

The effect of the aqueous extract of Retama raetam (RR) on blood glucose levels was investigated in fasting normal and streptozotocin-induced diabetic rats after single and repeated oral administration. The aqueous extract of RR at a dose of 20mg/kg significantly reduced the blood glucose in normal rats 6h after a single oral administration (P<0.005) and two weeks after repeated oral administration (P<0.05). This hypoglycaemic effect is more pronounced in streptozotocin (STZ) diabetic rats (P<0.001). The aqueous extract of RR had no effect on basal plasma insulin levels indicating that the underlying mechanism of RR activity is extra-pancreatic. These findings suggest that the aqueous extract of RR possess significant hypoglycaemic effect in both normal and STZ diabetic rats.     

Anti‐Hyperglycemic Effect of Fermented Ginseng in Type 2 Diabetes Mellitus Mouse Model

Ginseng has shown an efficacy in preventing and managing various health conditions. This study aimed to evaluate the effect of the fermented ginseng extract (FGE) in type 2 diabetes mellitus murine model. FGE was provided to male C57BL/ksJ‐db/db mice for 8 weeks at 0.1% (w/w) dose in contrast to water for the control group. Potential anti‐diabetic mechanisms were investigated with blood glucose, serum insulin, serum adiponectin, hemoglobin A1c (HbA1c), glucose tolerance, insulin secretion assay, quantitative real‐time polymerase chain reaction, and hematoxylin–eosin staining. Compared with the control group, the FGE group had lower levels of blood glucose after 6 and 9 h fasting, HbA1c, and the area under the curve in an oral glucose tolerance test and higher levels of adiponectin and serum insulin (p < 0.05). The FGE group had higher levels of peroxisome proliferator‐activated receptor gamma 2 and glucose transporter protein 2 mRNAs, a lower level of tumor necrosis factor‐α (TNF‐α) (p < 0.05), and less lymphocytes in pancreas than the control group had. The FGE exerted anti‐diabetic effects in type 2 diabetic mice. Copyright © 2012 John Wiley & Sons, Ltd.     

菩人丹对糖尿病大鼠降糖作用的研究

目的 :探讨菩人丹的降糖作用。方法 :用链脲佐菌素复制糖尿病大鼠模型 ,观察菩人丹对其血糖、血清胰岛素水平的影响 ;以小鼠为对象 ,做菩人丹的急性毒性实验。结果 :菩人丹可降低大鼠血糖 ,并存在时效关系 ;菩人丹各剂量组、二甲双胍组的空腹血糖较模型组均下降 (P <0 0 1) ,且菩人丹中剂量组与二甲双胍组比较有显著性差异 (P <0 0 5 )。菩人丹中剂量组能够升高血清胰岛素水平 ,与模型组比较有显著差异 (P <0 0 5 )。小鼠急性毒性实验表明 ,菩人丹无明显毒副作用。结论 :菩人丹可以降低实验性高血糖 ,提高糖尿病大鼠血清胰岛素水平 ,且无明显毒性作用