Hypoglycemic effect of aqueous extract of seabuckthorn (Hippophae rhamnoides L.) seed residues in streptozotocin‐induced diabetic rats

An extract of seabuckthorn (Hippophae rhamnoides L.) seed residues has been shown to possess hypoglycemic and hypolipidemic properties in normal mice. The present study investigated the effects of an aqueous extract of seabuckthorn seed residues (ASSR) on serum glucose, lipid profiles and antioxidant parameters in streptozotocin‐induced diabetic rats. Male Sprague‐Dawley rats were divided into four groups: a normal control group; diabetic control group; diabetic groups supplemented with 5 mg/kg body weight glibenclamide (reference drug) and 400 mg/kg body weight ASSR. Diabetes in rats was induced by intraperitoneal injection of streptozotocin (45 mg/kg body weight). Vehicle (distilled water), glibenclamide and ASSR were administered orally to normal and diabetic rats once a day lasting for 4 weeks. The data showed that administration of ASSR significantly lowered the serum glucose, triglyceride and nitric oxide levels in diabetic rats. Moreover, ASSR treatment also increased serum superoxide dismutase activity and glutathione level markedly. These results show that ASSR has hypoglycemic, hypotriglyceridemic and antioxidant effects in streptozotocin‐induced diabetic rats, suggesting that ASSR supplementation can be useful in preventing diabetic complications associated with hyperlipidemia and oxidative stress. Copyright © 2009 John Wiley & Sons, Ltd.     

Influence of tetrahydrocurcumin on erythrocyte membrane bound enzymes and antioxidant status in experimental type 2 diabetic rats

Curcuma longa (Zingiberaceae) has been used traditionally as antidiabetic and has been proven scientifically to possess high antioxidant activity and anticancer properties. The active components of Curcuma longa such as curcumin and tetrahydrocurcumin (THC), a major colourless metabolite of curcumin also possesses antidiabetic, antiinflammatory and antioxidant activity. In the present study the effect of THC and curcumin on erythrocyte membrane bound enzymes and antioxidants activity in streptozotocin (STZ) and nicotinamide induced type 2 diabetic model was investigated. Oral administration of THC at 80 mg/kg body weight to diabetic rats for 45 days. The effect of THC and curcumin on glucose, insulin, haemoglobin, glycosylated haemoglobin, thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), catalase (CAT), glutathione peroxide (Gpx), glutathione-S-transferase (GST), reduced glutathione (GSH) and membrane bound enzymes were studied. The effect of THC was compared with curcumin. The levels of blood glucose, glycosylated haemoglobin, erythrocyte TBARS, were increased significantly whereas the level of plasma insulin and haemoglobin, erythrocyte antioxidants (SOD, CAT, GPx, GST and GSH), membrane bound total ATPase, Na(+)/K(+)-ATPase, Ca(2+)-ATPase, Mg(2+)-ATPase were decreased significantly in diabetic rats. Administration of THC and curcumin to diabetic rats showed decreased level of blood glucose, glycosylated haemoglobin and erythrocyte TBARS. In addition the levels of plasma insulin, haemoglobin, erythrocyte antioxidants and the activities of membrane bound enzymes also were increased in THC and curcumin treated diabetic rats. These biochemical observations were supplemented by histopathological examination of pancreas section. The present study indicates that the THC possesses a significant beneficial effect on erythrocyte membrane bound enzymes and antioxidants defense in addition to its antidiabetic effect.     

Hypoglycemic activity and antioxidant potential of some medicinal plants traditionally used in Turkey for diabetes

Cydonia oblonga Mill. (Rosaceae) leaves, Helianthus tuberosus L. (Asteraceae) tubers, and Allium porrum L. (Liliaceae) bulbs are used as a folk remedy for the treatment of diabetes and they are also consumed as food in Turkey. In the present study, the antidiabetic and antioxidant activities of the ethanol extracts of these plants were studied in normal and streptozotocin-induced diabetic rats for 5 days. All extracts were administrated orally to rats at the doses of 250 and 500 mg/kg. Blood glucose level was measured according to glucose oxidase method. In order to determine antioxidant activity, thiobarbituric acid reactive substance (TBARS) and reduced glutathione (GSH) levels in liver, kidney, and heart tissues were measured by using spectrophotometric methods. Oral administration of Cydonia oblonga (500 mg/kg) and Allium porrum (500 mg/kg) extracts for 5 days in diabetic rats caused a decrease in blood glucose levels by 33.8% and 18.0%, respectively. Moreover, Allium porrum and Cydonia oblonga extracts induced significant alleviation on only heart tissue TBARS levels (44.6 and 45.7%), Helianthus tuberosus and Allium porrum extracts showed an inhibitory effect on kidney tissue TBARS levels (24.5 and 14.8%). None of the extracts restored GSH levels in kidney, liver, and heart tissues of diabetic rats.     

Effect of an antidiabetic extract of Catharanthus roseus on enzymic activities in streptozotocin induced diabetic rats.

Hypoglycemic activity was detected in dichloromethane:methanol extract (1:1) of leaves and twigs of Catharanthus roseus (family Apocynaceae), a traditionally used medicinal plant, using streptozotocin (STZ) induced diabetic rat model. Extract at dose 500 mg/kg given orally for 7 and 15 days showed 48.6 and 57.6% hypoglycemic activity, respectively. Prior treatment at the same dose for 30 days provided complete protection against STZ challenge (75 mg/kg/i.p.x1). Enzymic activities of glycogen synthase, glucose 6-phosphate-dehydrogenase, succinate dehydrogenase and malate dehydrogenase were decreased in liver of diabetic animals in comparison to normal and were significantly improved after treatment with extract at dose 500 mg/kg p.o. for 7 days. Results indicate increased metabolization of glucose in treated rats. Increased levels of lipid peroxidation measured as 2-thiobarbituric acid reactive substances (TBARS) indicative of oxidative stress in diabetic rats were also normalized by treatment with the extract.     

Effect of ethanolic extract of Zingiber officinale on dyslipidaemia in diabetic rats

The lipid lowering and antioxidant potential of ethanolic extract of Zingiber officinale Roscoe (family, Zingiberaceae) was evaluated in streptozotocin (STZ)-induced diabetes in rats. Ethanolic extract of Zingiber officinale (200 mg/kg) fed orally for 20 days produced, significant antihyperglycaemic effect (P < 0.01) in diabetic rats. Further, the extract treatment also lowered serum total cholesterol, triglycerides and increased the HDL-cholesterol levels when compared with pathogenic diabetic rats (P < 0.01). STZ-treatment also induced a statistically significant increase in liver and pancreas lipid peroxide levels (P < 0.01) as compared to normal healthy control rats. Zingiber officinale extract treatment lowered the liver and pancreas thiobarbituric acid reactive substances (TBARS) values (P < 0.01) as compared to pathogenic diabetic rats. The results of test drug were comparable to gliclazide (25 mg/kg, orally), a standard antihyperglycaemic agent. The results indicate that ethanolic extract of Zingiber officinale Roscoe can protect the tissues from lipid peroxidation. The extract also exhibit significant lipid lowering activity in diabetic rats. The present study is the first pilot study to assess the potential of Zingiber officinale in diabetic dyslipidaemia.     

Hypoglycaemic effect of Triticum repens P. Beauv. in normal and diabetic rats

The hypoglycaemic effect of an aqueous extract of Triticum repens (TR) rhizomes was investigated in normal and streptozotocin (STZ) diabetic rats. After a single oral administration of the aqueous extract (20mg/kg) a significant decrease on blood glucose levels in STZ diabetic rats (p<0.001) was observed; the blood glucose levels were normalized after 2 weeks of daily oral administration of TR aqueous extract (20mg/kg) (p<0.001). Significant reduction on blood glucose levels were noticed in normal rats after both acute (p<0.001) and chronic treatment (p<0.001). In addition, no changes were observed in basal plasma insulin concentrations after treatment in either normal or STZ diabetic rats indicating that the underlying mechanism of this pharmacological activity seems to be independent of insulin secretion. We conclude that the aqueous extract of TR exhibits a potent hypoglycaemic activity in STZ rats without affecting basal plasma insulin concentrations.     

Studies on the hypoglycaemic activity of Punica granatum seed in streptozotocin induced diabetic rats.

The hypoglycaemic activity of Punica granatum Linn. (Family Punicaceae) seed extract on rats made diabetic by streptozotocin (STZ) was investigated. The methanol extract of the seed at doses of 300 and 600 mg/kg, and chlorpropamide 200 mg/kg was administered to STZ diabetic rats. The seed extract (150, 300 and 600 mg/kg, orally) caused a significant reduction of blood glucose levels in STZ induced diabetic rats by 47% and 52%, respectively, at the end of 12 h.     

Study of the hypoglycaemic activity of Lepidium sativum L. aqueous extract in normal and diabetic rats

The hypoglycaemic effect of an aqueous extract of Lepidium sativum L. (LS) seeds was investigated in normal and streptozotocin (STZ)-induced diabetic rats. After a acute (single dose) or chronic (15 daily repeated administration) oral treatments, the aqueous LS extract (20 mg/kg) produced a significant decrease on blood glucose levels in STZ diabetic rats (p < 0.001); the blood glucose levels were normalised 2 weeks after daily repeated oral administration of aqueous LS extract (20 mg/kg) (p < 0.001). Significant reduction on blood glucose levels were noticed in normal rats after both acute (p < 0.01) and chronic treatment (p < 0.001). In addition, no changes were observed in basal plasma insulin concentrations after treatment either in normal or STZ diabetic rats indicating that the underlying mechanism of this pharmacological activity seems to be independent of insulin secretion. We conclude that the aqueous extract of LS exhibits a potent hypoglycaemic activity in rats without affecting basal plasma insulin concentrations.     

Protocatechuic Acid Restores Vascular Responses in Rats With Chronic Diabetes Induced by Streptozotocin

Oxidative stress has been shown to play an important role in development of vascular dysfunction in diabetes. Protocatechuic acid (PCA) has been reported to exert antioxidant and anti‐hyperglycemic activities. Diabetes was induced in male Sprague–Dawley rats by a single intraperitoneal injection of 50 mg/kg streptozotocin (STZ). The rats were maintained in a state of hyperglycemia for 12 weeks. Then, PCA (50 or 100 mg/kg/day) was administered orally or insulin (4 U/kg/day) was subcutaneous injected to the rats for 6 weeks. Blood pressure, vascular responses to vasoactive agents, vascular superoxide production, blood glucose, insulin, malondialdehyde, nitric oxide and antioxidant enzymes were examined. The diabetic rats showed weight loss, insulin deficiency, hyperglycemia, increased oxidative stress, decreased plasma nitric oxide, elevated blood pressure, increased vascular response to phenylephrine and decreased vascular responses to acetylcholine and sodium nitroprusside. PCA significantly decreased blood glucose and oxidative stress, and increased plasma nitric oxide in diabetic rats. Interestingly, PCA treatment restored blood pressure and vascular reactivity, and antioxidant enzyme activity diabetic rats. This study provides the first evidence of the efficacy of PCA in restoring the vascular reactivity of diabetic rats. The mechanism of action may be associated with an alleviation of oxidative stress. Copyright © 2015 John Wiley & Sons, Ltd.     

Ferulic acid alleviates lipid peroxidation in diabetic rats

Diabetes mellitus is a metabolic disorder associated with increased formation of free radicals. The objective of our study was to determine whether ferulic acid (FA), a phenolic acid, has any role to play in diabetes induced free radical formation. Diabetes was induced with streptozotocin. The levels of blood glucose, thiobarbituric acid reactive substances (TBARS), hydroperoxides and free fatty acids (FFA) increased in the liver of diabetic animals. The activities of glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) decreased in the liver. Histopathology of pancreas also shows shrunken islets. Supplementation of FA to the diabetic rats resulted in a decrease in the levels of glucose, TBARS, hydroperoxides, FFA and an increase in reduced glutathione (GSH). FA also resulted in increased activities of SOD, CAT, GPx and expansion of pancreatic islets. The effect was much pronounced with lower dose treatment. Thus our study shows that administration of ferulic acid helps in enhancing the antioxidant capacity of these diabetic animals by neutralizing the free radicals formed thereby reducing the intensity of diabetes.     

Antidiabetic and antioxidant effects of Annona muricata (Annonaceae), aqueous extract on streptozotocin-induced diabetic rats

Ethnopharmacological relevance

The leaves of Annona muricata are used in Cameroon to manage diabetes and its complications. The aim of this study was to evaluate the antidiabetic, antioxidant activities and the potential toxicity of aqueous extract of Annona muricata in streptozotocin-induced diabetic rats.

Material and methods

Oral administration of Annona muricata aqueous extract (100 mg/kg or 200 mg/kg) was studied in normal and streptozotocin-induced diabetic rats. In long term treatment, 2 weeks after streptozotocin-induced diabetic rats, animals received plant extract during 28 consecutive days. For a protective effect, extract was administered 3 days prior to streptozotocin exposure and animals were observed 2 weeks without treatment.

Results

The plant extract was not effective in normal rats. In diabetic rats, single administration of the extract significantly reduced blood glucose levels by 75% and 58.22% respectively at the dose of 100 mg/kg and 200 mg/kg as compared to the initial value. Treatment of normal rats 3 days prior to diabetes induction showed that, Annona muricata extract has no effect within 72 h following STZ injection. However, after 14 days post-treatment, the extract at the dose of 100 mg/kg significantly reduced blood glucose levels as compared with initial value and diabetic control rats. Immunohistochemical staining of pancreatic β-cells of diabetic rats treated with the dose of 100 mg/kg expressed strong staining for β-cell compared to diabetic control. In a long-term study daily administration of Annona muricata aqueous extract for 28 days to diabetic rats, reduced blood glucose levels, serum creatinine, MDA, AST, ALT activity, and nitrite levels LDL-cholesterol. Total cholesterol, triglycerides, SOD, and CAT activity contents were restored.

Conclusion

These different results show that the antidiabetic activity of Annona muricata aqueous extract can be explained by its hypolipidaemic effect, its antioxidant and protective action on pancreatic β-cells, which in turn improve glucose metabolism.     

Protective effect of diosmin against diabetic neuropathy in experimental rats

OBJECTIVE:The present study was undertaken to evaluate the effect of diosmin in diabetic neuropathy in type 2 diabetic rats.METHODS:Type 2 diabetes was induced in male Sprague-Dawley rats by single intraperitoneal injection of streptozotocin(35 mg/kg) and high-fat diet.Four weeks after the confirmation of diabetes,diabetic rats were treated with diosmin(50 and 100 mg/kg,p.o.) for next 4 weeks.Rats were evaluated for biochemical,behavioral and oxidative stress parameters.Eddy's hot plate and tail immersion test were performed on 6th,7th,8th,9th and 10th weeks of experiment to assess thermal hyperalgesia and cold allodynia respectively.Further,the walking function test was performed for assessing the motor responses at the end of the treatment schedule.RESULTS:Rats were fed with high-fat diet throughout the experiment schedule and administration of low-dose streptozotocin induced significant elevation in blood glucose level and insulin resistance which was confirmed by oral glucose tolerance test.Treatment with diosmin at doses of 50 and 100 mg/kg significantly restored the reduced body weight,elevated blood sugar and lipid profiles.Further the dose-dependent improvement was observed in thermal hyperalgesia,cold allodynia and walking function in diabetic rats treated with diosmin.Elevated levels of malondialdehyde,and nitric oxide and decreased glutathione levels and superoxide dismutase activity in diabetic rats were restored significantly after the 4 weeks of diosmin treatment.CONCLUSION:Diosmin has shown beneficial effect in preventing the progression of early diabetic neuropathy in rats.     

Antioxidant and protective effect of latex of Calotropis procera against alloxan-induced diabetes in rats

In the present study, dry latex (DL) of Calotropis procera possessing potent anti-inflammatory activity was evaluated for its antioxidant and anti-hyperglycemic effects against alloxan-induced diabetes in rats. Daily oral administration of DL at 100 and 400 mg/kg doses produced a dose-dependent decrease in the blood glucose and increase in the hepatic glycogen content. DL also prevented the loss of body weight in diabetic rats and brought down the daily water consumption to values comparable to normal rats. DL also produced an increase in the hepatic levels of the endogenous antioxidants, namely superoxide dismutase (SOD), catalase and glutathione, while it brought down the levels of thiobarbituric acid-reactive substances (TBARS) in alloxan-induced diabetic rats. The efficacy of DL as an antioxidant and as an anti-diabetic agent was comparable to the standard anti-diabetic drug, glibenclamide.     

Antihyperglycemic and hypolipidemic effects of Costus speciosus in alloxan induced diabetic rats

Hyperglycemia, abnormal lipid and antioxidant profiles are the most usual complications in diabetes mellitus. In the present study, the antihyperglycemic, antihyperlipemic and antioxidant potency of an ethanol extract of Costus speciosus root was investigated in alloxan-induced diabetic male (Charles Foster) rats. Four groups of alloxan diabetic rats (n = 6) were administered orally with different doses of Costus speciosus root extract (150, 300 and 450 mg/kg BW) and a standard drug, glibenclamide (600 microg/kg BW), for 4 weeks. Two groups of rats (n = 6) served as normal and diabetic controls. While the diabetic controls showed significant abnormal carbohydrate, lipid and antioxidant profiles, administration of 150 mg/kg BW dose neither improved glucose nor lipid metabolism and antioxidant levels. Administration of 300 and 450 mg/kg BW doses, however, resulted in a reversal of diabetes and its complications. Both doses significantly brought down blood glucose concentration (26.76%, 34.68%), increased glycogenesis and decreased glyconeogenesis bringing the glucose metabolism toward normalcy. These doses also reversed the hyperlipidemia by reducing plasma total lipid (12.87%, 178.24%), cholesterol (21.92%, 30.77%) and triglyceride (25.32%, 33.99%) and improved hepatic antioxidant enzyme activities. The high dose (450 mg/kg BW) was found to have more potential antioxidant activities compared with glibenclamide. It is concluded that Costus speciosus root extract possesses anti-hyperglycemic, antihyperlipemic and antioxidative effects, which may prove to be of clinical importance in the management of diabetes and its complications.     

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.     

Hypoglycaemic activity of Leucas lavandulaefolia Rees. in streptozotocin-induced diabetic rats

The antidiabetic activity of Leucas lavandulaefolia Rees (Family - Labiatae) extract on streptozotocin (STZ) induced diabetic rats has been investigated. A methanol extract of the herb at doses of 200 and 400 mg/kg, and glybenclamide (1 mg/kg) were administered concurrently to STZ-diabetic rats. The extract caused a significant reduction of blood glucose levels in streptozotocin-induced diabetic rats by 29.8% (p <0.001) compared with control groups. © 1997 John Wiley & Sons, Ltd.     

桑精胶囊改善2型糖尿病大鼠胰岛素抵抗及其分子机制的研究

目的观察桑精胶囊对2型糖尿病大鼠胰岛素抵抗的治疗效应及其分子机制。方法应用小剂量链脲佐茵素加高热量饲料饲养的方法建立实验性2型糖尿病大鼠模型,观察桑精胶囊灌胃6周对葡萄糖耐量、血清胰岛素、甘油三酯、总胆固醇、高密度脂蛋白-胆固醇、游离脂肪酸和胰岛素敏感性指数的影响,以逆转录聚合酶链式反应(RT-PCR)测定肝脏胰岛素样生长因子1(IGF-1)mRNA表达及蛋白印迹(Western-blot)检测骨骼肌葡萄糖转运子4(GLUT4)水平。结果桑精胶囊能减轻2型糖尿病大鼠体重,改善糖耐量和调节脂代谢,降低血清游离脂肪酸,减轻高胰岛素血症,提高胰岛素敏感性,且表现为剂量-效应关系。与正常组相比,模型组肝脏IGF-1 mRNA表达水平及骨骼肌GLUT4含量及胰岛素敏感指数明显下降(P＜0．01)；与模型组相比,桑精胶囊组肝脏IGF-1 mRNA及骨骼肌GLUT4含量表达明显上升(P＜0．01或P＜0．05)。结论桑精胶囊能改善2型糖尿病大鼠之胰岛素抵抗,并可能与其改善脂代谢,降低游离脂肪酸有关,其分子机制可能与增加骨骼肌GLUT4蛋白含量,上调肝脏IGF-1 mR- NA表达水平有关。     

Effects of parsley (Petroselinum crispum) extract versus glibornuride on the liver of streptozotocin-induced diabetic rats

Parsley (Petroselinum crispum) is one of the medicinal herbs used by diabetics in Turkey. The aim of this study is to investigate the effects of parsley (2g/kg) and glibornuride (5mg/kg) on the liver tissue of streptozotocin-induced diabetic rats. Swiss albino rats were divided into six groups: control; control+parsley; control+glibornuride; diabetic; diabetic+parsley; diabetic+glibornuride. Diabetes was induced by intraperitoneal injection of 65 mg/kg streptozotocin (STZ). Parsley extract and glibornuride were given daily to both diabetic and control rats separately, until the end of the experiment, at day 42. The drugs were administered to one diabetic and one control group from days 14 to 42. On day 42, liver tissues were taken from each rat. In STZ-diabetic group, blood glucose levels, serum alkaline phosphatase activity, uric acid, sialic acid, sodium and potassium levels, liver lipid peroxidation (LPO), and non-enzymatic glycosylation (NEG) levels increased, while liver glutathione (GSH) levels and body weight decreased. In the diabetic group given parsley, blood glucose, serum alkaline phosphatase activity, sialic acid, uric acid, potassium and sodium levels, and liver LPO and NEG levels decreased, but GSH levels increased. The diabetic group, given glibornuride, blood glucose, serum alkaline phosphatase activity, serum sialic acid, uric acid, potassium, and liver NEG levels decreased, but liver LPO, GSH, serum sodium levels, and body weight increased. It was concluded that probably, due to its antioxidant property, parsley extract has a protective effect comparable to glibornuride against hepatotoxicity caused by diabetes.     

川芎嗪对糖尿病大鼠肾损伤的保护作用及相关蛋白nephrin和podocin表达的影响

目的:研究川芎嗪对高脂高糖饮食与链脲佐菌素(STZ)诱致大鼠肾脏损伤的保护作用及与相关蛋白nephrin,podocin表达的影响。方法 :将50只雄性大鼠随机分为正常组和模型组。除正常组外,其余大鼠均给予高脂-高糖饲料喂养4周,再给予STZ(40 mg/kg,ip)注射,72h后测定空腹血糖,将血糖值大于16.67mmol/L的大鼠随机分为4组:模型组,二甲双胍组(250 mg/kg),川芎嗪低剂量组(80mg/kg)和高剂量组(160mg/kg),连续给药8周。末次给药后,收集24h尿液,测定尿蛋白含量;取血测定血糖、血肌酐、尿素氮变化;光镜下观察肾脏病理学变化;Western Blot方法检测肾组织nephrin、podocin蛋白表达水平。结果:模型大鼠血糖值明显高于正常对照组,尿蛋白含量、血肌酐、尿素氮含量亦明显升高,肾组织nephrin、podocin蛋白表达水平降低。低高剂量川芎嗪治疗8周后,明显改善血糖水平,降低尿蛋白含量、血肌酐和尿素氮含量;肾组织nephrin和podocin蛋白表达增加,肾脏组织病理性损伤明显减轻。结论:川芎嗪对高糖高脂饮食与STZ诱致糖尿病大鼠肾损伤具有保护作用,其机制可能与诱导nephrin,podocin表达增加有关。     

The effect of Momordica charantia and Mucuna pruriens in experimental diabetes and their effect on key metabolic enzymes involved in carbohydrate metabolism

The Indian traditional system of medicine prescribed traditional plant therapies. Two such plants, i.e. Momordica charantia (MC) and Mucuna pruriens (MP), earlier shown to reduce hyperglycaemia, were assessed for their anti hyperglycaemic effect on varying degrees of hyperglycaemia and diabetic complications. Alcohol and aqueous extracts of MC (50, 100 and 200 mg/kg/day) and only an alcohol extract of MP (100, 200 and 400 mg/kg/day) were evaluated in a pilot study (plasma glucose >180 mg/dL, 21 days), a chronic study in alloxanized rats (plasma glucose >280mg/dL, 120 days) and streptozotocin (STZ) mice (plasma glucose >400 mg/dL, 60 days). In the pilot study, the maximum antihyperglycaemic effect occurred with an aqueous extract of MC at week 3 and an alcohol extract of MP at week 6 at a dose of 200 mg/kg/day. In chronic alloxanized rats, the selected dose of MC led to a significant fall of 64.33%, 66.96%, 69.7% and 70.53% in plasma glucose levels at 1, 2, 3 and 4 months, respectively. MP showed a decrease of 40.71%, 45.63%, 50.33% and 51.01% at the same time period. In chronic STZ diabetic mice, MC led to a mean reduction of 15.37%, 18.68% and 22.86% in plasma glucose levels on days 40, 50 and 60 of sampling while MP had no significant effect. The alteration in hepatic and skeletal muscle glycogen content and hepatic glucokinase, hexokinase, glucose-6-phosphate and phosphofructokinase levels in diabetic mice were partially restored by MC but not by MP. The mechanism of action of MC and MP is discussed.