Evaluation of antihyperglycemic and antioxidant properties of Streblus asper Lour against streptozotocin–induced diabetes in rats

ObjectiveTo evaluate antidiabetic and antioxidant role of methanol extract of Streblus asper (S. asper) root bark in Wistar rats.MethodsDiabetes was induced in rats by single intraperitoneal injection of streptozotocin (STZ, 65 mg/kg body weight). Three days after STZ induction, the diabetic rats were treated with S. asper orally at dose of 200 and 400 mg/kg body weight daily for 15 days. Glibenclamide (0.25 mg/kg, orally) was used as reference drug. The fasting blood glucose levels were measured on every fifth day during the 15-day treatment. Serum biochemical parameters such as serum glutamate pyruvate transaminase, serum glutamate oxaloacetate transaminase, serum alkaline phosphatase, total cholesterol total protein and serum triglycerides were estimated. Antioxidant properties were assessed by estimating liver and kidney thiobarbituric acid reactive substances, reduced glutathione and catalase.ResultsS. asper in STZ-induced diabetic rats, at doses of 200 and 400 mg/kg bw produced reduction in blood glucose levels when compared with the STZ control group. Serum biochemical parameters antioxidant levels were significantly restored toward normal levels in S. asper treated rats as compared with STZ control.ConclusionsThe present study infers that the methanol extract of S. asper root bark demonstrated remarkable antidiabetic activity in STZ-induced diabetic rats. The potential antidiabetic action is plausibly due to its underlying antioxidant role.     

Antidiabetic and antihyperlipidaemic potential of Amaranthus viridis (L.) Merr. in streptozotocin induced diabetic rats

ObjectiveThe present study is planned to investigate the antidiabetic and antihyperlipidaemic potential of Amaranthus viridis stem aqueous extract (AVSAE) in Stz-induced diabetic rats.MethodsDiabetes was induced in rats by single intraperitoneal injection of STZ (55mg/kg b.wt.). After 72 h rats with marked hyperglycaemia (fasting blood glucose ≥250 mg/dl) were selected and used for the study. Antidiabetic activity was evaluated by administration of AVSAE orally at the doses of 100,200 and 400 mg/kg body weight for 30 days. Glibenclamide (500 ug/kg) was used as the reference drug. Fasting blood glucose and lipid parameters, viz. triglycerides, total cholesterol, high density lipoprotein and low density lipoprotein levels were measured.ResultsIn STZ-induced diabetic rats, repeated administration of AVSAE significantly (P < 0.05) decreased the blood glucose level in a dose-dependent manner during the 30 days of treatment period. AVSAE modulated lipid profile changes in STZ-diabetic rats in a dose-dependent manner.ConclusionsThe significant control of serum lipids levels in the AVSAE treated diabetic rats may be directly attributed to improvement in glycemic control upon AVSAE therapy. Hence, these findings demonstrate that Amaranthus viridis has the potential to treat diabetes mellitus and complications owing to its antidiabetic and antihyperlipidaemic effect.     

Evaluation of the anti-diabetic properties of Mucuna pruriens seed extract

ObjectiveTo explore the antidiabetic properties of Mucuna pruriens(M. pruriens).MethodsDiabetes was induced in Wistar rats by single intravenous injection of 120 mg/kg of alloxan monohydrate and different doses of the extract were administered to diabetic rats. The blood glucose level was determined using a glucometer and results were compared with normal and untreated diabetic rats. The acute toxicity was also determined in albino mice.ResultsResults showed that the administration of 5, 10, 20, 30, 40, 50, and 100 mg/kg of the crude ethanolic extract of M. pruriens seeds to alloxan-induced diabetic rats (plasma glucose > 450 mg/dL) resulted in 18.6%, 24.9%, 30.8%, 41.4%, 49.7%, 53.1% and 55.4% reduction, respectively in blood glucose level of the diabetic rats after 8h of treatment while the administration of glibenclamide (5 mg/kg/day) resulted in 59.7% reduction. Chronic administration of the extract resulted in a significant dose dependent reduction in the blood glucose level (P<0.001). It also showed that the antidiabetic activity of M. pruriens seeds resides in the methanolic and ethanolic fractions of the extract. Acute toxicity studies indicated that the extract was relatively safe at low doses, although some adverse reactions were observed at higher doses (8-32 mg/kg body weight), no death was recorded. Furthermore, oral administration of M. pruriens seed extract also significantly reduced the weight loss associated with diabetes.ConclusionsThe study clearly supports the traditional use of M. pruriens for the treatment of diabetes and indicates that the plant could be a good source of potent antidiabetic drug.     

Antidiabetic activity of aqueous root extract of Merremia tridentata (L.) Hall. f. in streptozotocin-induced-diabetic rats

ObjectiveTo investigate the antidiabetic effect of aqueous extract of Merremia tridentata (M. tridentata) root (MTRAE) in normal, glucose-loaded hyperglycemic and streptozotocin (STZ)-induced diabetic rats.MethodsOral administration of MTRAE at the doses of 50, 100 and 150 mg/kg was studied in normal, glucose-loaded and STZ-diabetic rats. The three doses caused significant reduction in blood glucose levels in all the models.ResultsThe effect was more pronounced in 100 and 150 mg/kg than 50 mg/kg. MTRAE also showed significant increase in serum insulin, body weight and glycogen content in liver and skeletal muscle of STZ-induced diabetic rats while there was significant reduction in the levels of serum triglyceride and total cholesterol. MTRAE also showed significant antilipidperoxidative effect in the pancreas of STZ-induced diabetic rats. The antidiabetic effect of M. tridentata was compared with glibenclamide, a well known hypoglycemic drug.ConclusionsThe results indicate that aqueous extract of M. tridentata root possesses significant antidiabetic activity.     

Antidiabetic, hypolipidemic and histopathological analysis of Dillenia indica (L.) leaves extract on alloxan induced diabetic rats

ObjectiveTo investigate antidiabetic, hypolipidemic histopathological analysis of Dillenia indica (D. indica) methanolic leaves (DIME) extract in alloxan induced diabetic rat by administering oral doses (250 and 500 mg/kg body weight).MethodsBlood glucose levels were measured using blood glucose test strips with elegance glucometer on weekly intervals till the end of study (i.e. 3 weeks). Other parameters e.g. liver profile, renal profile and total lipid levels were determined in normal and alloxan induced diabetic rats after oral administration of the extract for 21 days. Histopathological changes in diabetic rat organs (pancreas, liver and kidney) were also observed after extract treatment.ResultsDaily oral administration DIME (250 and 500 mg/kg body weight) and glibenclamide (10 mg/kg) showed beneficial effects on blood glucose level (P < 0.001) as well as improving kidney, liver functions and hyperlipidaemia due to diabetes. The extract treatment also showed to enhanced serum insulin level and body weight of diabetic rats as compared to diabetic control group. Furthermore, the extract has a favorable effect on the histopathological changes of the pancreas, liver and kidney in alloxan induced diabetes.ConclusionsD. indica possess antidiabetic property as well improve body weight, liver profile, renal profile and total lipid levels. DIME has also favorable effect to inhibit the histopathological changes of the pancreas and kidney in alloxan induced diabetes.     

Effect of ethanolic extract of seeds of Linum usitatissimum (Linn.) in hyperglycaemia associated ROS production in PBMNCs and pancreatic tissue of alloxan induced diabetic rats

ObjectiveTo evaluate the effect of ethanolic extract of seeds of Linum usitatissimum (EELU) in hyperglycemia associated reactive oxygen species (ROS) production in peripheral blood mononuclear cells (PBMNCs) and pancreatic antioxidant enzymes in alloxan induced diabetic rat.MethodsDiabetes was induced in male Wistar rats by alloxan (120 mg/kg, i.p.). After acute and subacute treatment serum glucose was determined. Oral glucose tolerance test (OGTT) was performed in EELU pretreated animals. ROS production in PBMNCs and pancreatic antioxidant enzymes were measured in alloxan induced diabetic rat.ResultsOur results showed that, treatment of EELU (200 and 400 mg/kg) significantly reduced serum glucose level in acute and subacute study. The antihyperglycaemic effects of EELU showed onset at 4th h (P<0.001) and peak effect at 6th h (P<0.001). The effect was sustained until 24th h with 400 mg/kg. In subacute study, significant antihyperglycaemic effect was observed from 14th day (P<0.001) onwards. In EELU treated rat the body weight was significantly (P<0.001) increased as compared to diabetic group on 21st day onwards. In OGTT, increased glucose utilization was observed. Treatment of EELU 400 mg/kg showed significant reversal in pancreatic GSH (P<0.01) and SOD (P<0.05) indicating antioxidant nature of EELU. Flow cytometric estimation of total ROS production in PBMNCs in diabetic rats was significantly increased (P<0.001), whereas EELU treatment showed significant (P<0.001) decrease in PBMNCs ROS.ConclusionsIt is concluded from the investigation that EELU showed antihyperglycaemic effect mediated through inhibition of ROS level in PBMNCs and preservation of endogenous antioxidant enzymes in pancreatic tissue in alloxan induced diabetic rat.     

Antihyperglycemic effects of the methanol leaf extract of Diaphananthe bidens in normoglycemic and streptozotocin-induced hyperglycemic rats

ObjectiveTo evaluate the methanol leaf extract of Diaphanathe bidens (D. bidens) (AFZEL. EX SW) SCHLTR for antihyperglycemic activity in order to confirm it antidiabetic potential.MethodsD. bidens was extracted by cold maceration for 48 h and concentrated in vacuo to yield D. bidens extract (DBE). Hyperglycemia was induced by intraperitoneal administration of streptozotocin (75 mg/kg). Oral glucose tolerance test was done with 2 g/kg glucose load in normal rats. DBE (150, 300 and 600 mg/kg) was administered orally, while tolbutamide (100 mg/kg, p.o.) was used as the standard reference drug. Blood glucose levels determined using ACCUCHEK glucose auto-analyzer. The acute toxicity and phytochemical studies were also carried out.ResultsDBE (600 mg/kg) and tolbutamide (100 mg/kg) significantly (P<0.05, 0.005) reduced blood glucose levels of rats between 120 and 480 min post administration in normal rats. In the streptozotocin- induced hyperglycemic rats, DBE (150, 300, 600 mg/kg) caused significant (P<0.001) dose- and time- dependent reduction in the blood glucose levels by 1.7%, 22.8% and 43.4%, respectively at 480 min compared to the negative control group. DBE (600 mg/kg) reduced the blood glucose level of rats by 1.2% in the oral glucose tolerance test when compared with the normal saline treated group. The acute toxicity test showed that DBE was safe at the doses used and the phytochemical screening revealed the presence of saponins, steroids, tannins and terpernoids.ConclusionsD. bidens extract possess antihyperglycemic activity which may be mediated through pancreatic and extra-pancreatic pathways, thereby justifying it folkloric use.     

Effects of Gmelina arborea extract on experimentally induced diabetes

ObjectiveTo study the effects of aqueous extract of Gmelina arborea bark on normoglycemic levels and streptozotocin (STZ) induced diabetes in rats.MethodsAfter single administration of the aqueous extract, plasma glucose level was determined up to 6 h. In subacute study, the aqueous extract was administered for 28 d and plasma glucose level was determined weekly. The diabetes was induced in rats by the intraperitoneal injection of STZ at a dose of 55 mg/kg body weight. The diabetic animals were divided into four groups containing six in each: Group I diabetic control, Group II and III treated with the aqueous extract respectively at a dose of 250 and 500 mg/kg body weight once daily and Group IV treated with glibenclamide at a dose of 0.6 mg/kg body weight once daily. In acute study, the aqueous extract and glibenclamide were administered orally to rats. Plasma glucose levels were determined at 30, 60, 120, 240 and 360 min after the administration of the test samples. To study subacute effects, test samples (the aqueous extract and glibenclamide) were administered for 28 d consecutively. The effects of each test sample on plasma glucose level, body weight as well as food and water intake were also monitored weekly. The oral glucose tolerance test and biochemical indicators were estimated on day 28.ResultsThe aqueous extract did not significantly decrease the plasma glucose level in the normoglycemic rats as shown by the acute and subacute assays. However, after oral administration of the aqueous extract, the plasma glucose level was significantly (P<0.001) decreased in the diabetic rats in the acute study. The long-term administration of the aqueous extract significantly (P<0.001) reduced plasma glucose levels of the diabetic rats. Additionally, the aqueous extract also reduced loss of body weight and significantly decreased food and water intake in the diabetic animals. Nevertheless, no effects on biochemical indicators were observed at the selected doses.ConclusionsThe aqueous extract of Gmelina arborea bark had antihyperglycemic activity against STZ induced diabetes in rats, after single and subacute oral administration. Moreover, it did not show significant glucose lowering effect in normoglycemic rats.     

Hypoglycemic effect of Octomeles sumatrana aqueous extract in streptozotocin–induced diabetic rats and its molecular mechanisms

ObjectiveTo investigate the hypoglycemic effect of the aqueous extract of Octomeles sumatrana (O. sumatrana) (OS) in streptozotocin-induced diabetic rats (STZ) and its molecular mechanisms.MethodsDiabetes was induced by intraperitoneal (i.p.) injection of streptozotocin (55 mg/kg) in to male Sprague-Dawley rats. Rats were divided into six different groups; normal control rats were not induced with STZ and served as reference, STZ diabetic control rats were given normal saline. Three groups were treated with OS aqueous extract at 0.2, 0.3 and 0.5 g/kg, orally twice daily continuously for 21 d. The fifth group was treated with glibenclamide (6 mg/kg) in aqueous solution orally continuously for 21 d. After completion of the treatment period, biochemical parameters and expression levels of glucose transporter 2 (Slc2a2), glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PCK1) were determined in liver by quantitative real time PCR.ResultsAdministration of OS at different doses to STZ induced diabetic rats, resulted in significant decrease (P<0.05) in blood glucose level in a dose dependent manner by 36%, 48%, and 64% at doses of 0.2, 0.3 and 0.5 g/kg, respectively, in comparison to the STZ control values. Treatment with OS elicited an increase in the expression level of Slc2a2 gene but reduced the expression of G6Pase and PCK1 genes. Morefore, OS treated rats, showed significantly lower levels of serum alanine transaminase (ALT), aspartate aminotransferase (AST) and urea levels compared to STZ untreated rats. The extract at different doses elicited signs of recovery in body weight gain when compared to STZ diabetic controls although food and water consumption were significantly lower in treated groups compared to STZ diabetic control group.ConclusionsO. sumatrana aqueous extract is beneficial for improvement of hyperglycemia by increasing gene expression of liver Slc2a2 and reducing expression of G6Pase and PCK1 genes in streptozotocin-induced diabetic rats.     

Hypoglycemic and hypolipidemic activity of Hibiscus rosa sinensis Linn on streptozotocin–induced diabetic rats

To investigate the hypoglycemic activity of an aqueous extract of the flower of Hibiscus rosa sinensis on blood glucose in normal and streptozotocin (STZ) -induced diabetic rats, serum triglyceride and cholesterol levels and the effect of the flower extract on insulin secretion. Effect of H. rosa sinensis flower extract on blood glucose was studied with fed, fasted and glucose-loaded diabetic and nondiabetic rats. Glycosylated hemoglobin, serum insulin levels and lipid profile were also determined. Student??s t test was used for statistical analysis. In normal rats, the aqueous extract of the flower of H. rosa sinensis (250 and 500?mg/kg body weight) significantly (P?<?0.001) reduced the blood glucose levels after an oral glucose load from 127.9?±?5.6 to 80.6?±?3.9?mg/dl 2?h after oral administration of the flower extract. It also significantly lowered the blood glucose in STZ diabetic rats from 241.0?±?6.6 to 90.8?±?5.7?mg/dl after 21?days of oral administration of the extract (P?<?0.001). Serum insulin levels were not stimulated in the animals treated with the extract. Glycosylated hemoglobin and serum lipid profiles were significantly lowered by the administration of the extract. From the studies, it can be concluded that the aqueous extract of the flowers of H. rosa sinensis at a dosage of 500?mg/kg/day exhibits significant hypoglycemic and hypolipidemic activities. A marked reduction in glycosylated hemoglobin was also observed while insulin levels did not show any significant change.     

Antidiabetic potentials of the methanol leaf extract of Oxytenanthera abyssinica

Oxytenathera abyssinica is used for the treatment of diabetes mellitus in folklore medicine in Nigeria. In this study, we evaluated its antidiabetic activity in alloxan-induced diabetic mice. Diabetes was induced in the mice by a single intraperitoneal injection of alloxan monohydrate and the fasting blood glucose (FBG) levels measured with blood from the tail snip at 0, 1, 3 and 6 h. The activity was compared with reference drug, glibenclamide (2 mg/kg) and negative control. Oral glucose tolerance test (OGTT) was evaluated by loading glucose to rats at the dose of 2,000 mg/kg and checking their FBG at 0, 60 and 180 min. Antioxidant activity was evaluated using ferric reducing antioxidant power (FRAP) and 1, 1- diphenyl-2- hydrazyl (DPPH) photometric assay. The extract and the reference drug caused a significant (P?<?0.02–P?<?0.002) time and dose dependent decrease in the FBG levels of the mice when compared to the negative control; the extract (500 mg/kg) reduced FBG by 38.0 % at the 6th hr as against 45.6 % by glibenclamide. In OGTT the extract caused a time dependent decrease in the blood glucose level up to 33.3 % at 180 min at the dose of 300 mg/kg. The extract also caused a concentration dependent increase in antioxidant activity having 91 % increase and 1.95 total antioxidant activities at a concentration of 400 μg/ml. Extract of Oxythenanthera abyssinica showed significant antidiabetic activity.     

Ameliorating effect of Semecarpus anacardium Linn. nut milk extract on altered glucose metabolism in high fat diet STZ induced type 2 diabetic rats

ObjectiveTo explore the protective effect of the drug Semecarpus anacardium (S. anacardium)on altered glucose metabolism in diabetic rats.MethodsType 2 diabetes mellitus was induced by feeding rats with high fat diet followed by single intraperitoneal injection of streptozotocin (STZ) (35 mg/kg b.w.). Seven days after STZ induction, diabetic rats received nut milk extract of S. anacardium Linn. nut milk extract orally at a dosage of 200 mg/kg daily for 4 weeks. The effect of nut milk extract of S. anacardium on blood glucose, plasma insulin, glucose metabolising enzymes and GSK were studied.ResultsTreatment with SA extract showed a significant reduction in blood glucose levels and increase in plasma insulin levels and also increase in HOMA – β and decrease in HOMA -IR. The drug significantly increased the activity of glycolytic enzymes and glucose-6-phosphate dehydrogenase activity and increased the glycogen content in liver of diabetic rats while reducing the activities of gluconeogenic enzymes. The drug also effectively ameliorated the alterations in GSK-3 mRNA expression.ConclusionsOverall, the present study demonstrates the possible mechanism of glucose regulation of S. anacardium suggestive of its therapeutic potential for the management of diabetes mellitus.     

Investigation of dose-dependent effects of berberine against renal ischemia/reperfusion injury in experimental diabetic rats

BackgroundIschemia–reperfusion injury causes various severe morphological and functional changes in diabetic patients. To date, numerous antidiabetic and antioxidant agents have been used for treatment of the disease-related changes.ObjectivesWe aimed to examine effective therapeutic doses or doses of berberine against renal ischemia/reperfusion injury (IRI) in a streptozotocin (STZ)-induced diabetic rat model by histopathological and biochemical analysis.MethodsThirty male Sprague Dawley rats were treated with STZ injection for the development of diabetes, and divided into the following groups: STZ-induced diabetic group (STZ); IRI-induced diabetic group (STZ + IRI); 50 mg/kg berberine (BRB) treated diabetic group after inducing IRI (STZ + IRI + BRB₁); 100 mg/kg BRB treated diabetic group after IRI (STZ + IRI + BRB₂); 150 mg/kg BRB treated diabetic group after IRI (STZ + IRI + BRB₃). Bilateral renal ischemia model was applied for 45 min, then reperfusion was allowed for 14 days in STZ-induced diabetic rats. Renal injury was detected histopathologically. Blood urea nitrogen (BUN), creatinine and lactate dehydrogenase (LDH) levels were measured in serum using the ELISA method. Total antioxidant status (TAS) and total oxidant status (TOS) of renal tissue was studied by spectrophotometric assay. Oxidative stress index (OSI) was calculated as TOS-to-TAS ratio. Tumor necrosis factor alpha (TNF-α), C-reactive protein (CRP), Na⁺/K⁺-ATPase (sodium pump), and Ca²⁺-ATPase (calcium ATPase) enzyme levels were measured in tissues using the ELISA method. Anti-apoptotic Bax and pro-apoptotic Bcl-2 protein levels were detected by Western blot analysis. All data were evaluated statistically.ResultsThe highest histopathological score was detected in the STZ + IRI group compared to the other group. BRB administration at the doses of 100 mg/kg and 150 mg/kg markedly improved renal injury. BUN and creatinine levels significantly increased in the STZ + IRI group compared to the STZ group (p < 0.001). 100 mg/kg and 150 mg/kg BRB administration significantly decreased those levels (p < 0.01). The highest TOS and the lowest TAS levels were detected in the STZ + IRI group (p < 0.001). IRI markedly aggravated inflammation via increasing levels of TNF-α and CRP (<0.001), and caused apoptosis via inducing Bcl-2 protein, and suppressing Bax protein (p < 0.001). BRB administration at the doses of 100 mg/kg and 150 mg/kg showed anti-oxidant, anti-inflammatory and anti-apoptotic effects (p < 0.01). The LDH enzyme, was used as a necrosis marker, was higher in the STZ + IRI group than other groups. BRB administration at all of the doses, resulted in the decline of LDH enzyme level (p < 0.001). Ca²⁺-ATPase and Na⁺/K⁺-ATPase enzyme activities decreased in the STZ + IRI group compared to the STZ group (p < 0.001), while BRB administration at the doses of 100 mg/kg and 150 mg/kg significantly increased those of enzyme activities, respectively (p < 0.05).ConclusionIschemia with diabetes caused severe histopathological and biochemical damage in renal tissue. The high doses of berberine markedly improved histopathological findings, regulated kidney function via decreasing BUN and creatinine levels, and rearranged intercellular ion concentration via increasing Na⁺/K⁺-ATPase and Ca^2+? ATPase levels. Berberine showed anti-oxidant, anti-apoptotic, and anti-inflammatory effects. According to these data, we suggest that berberine at the doses of 100 and 150 mg may be used as a potential therapeutic agent to prevent renal ischemic injury.     

Methanolic extract of African mistletoe (Viscum album) improves carbohydrate metabolism and hyperlipidemia in streptozotocin-induced diabetic rats

ObjectiveTo justify the use of African mistletoe (AM) Viscum album (V. album) in folkoric medicine to treat diabetes.MethodsIn one experiment, the fasting blood glucose (FBG) levels of diabetic rats were monitored for 4 h. Diabetic rats were treated with AM at doses of 50 mg/kg (AM1) and 100 mg/kg (AM2), glibenclamide (GB) (positive control) and saline solution (SS). In another experiment, diabetic rats were treated with AM2, GB and SS daily for 3 weeks.ResultsAM1 and AM2 elicited significant (P<0.05) hypoglycaemic effects within 4 h of extract administration. AM1 and AM2 decreased the FBG by 41% and 49%, respectively, at 2 h. AM2 was found to lower FBG by 51%, relative to baseline, which was comparable to GB at 3 h. In the second experiment, AM2 and GB significantly (P<0.05) decreased the FBG by 34% and 51%, respectively. This was followed by marked decrease in levels of HbA1C in AM2- and GB- treated diabetic rats. AM2 significantly (P<0.05) decreased the STZ-induced increase in levels of serum triglyceride, urea, lactate dehydrogenase, α-amylase and low-density lipoprotein-cholesterol. Furthermore, diabetic rats treated with AM2 had significantly (P<0.05) elevated high-density lipoprotein-cholesterol. In contrast, STZ administration produced insignificant (P<0.05) effect on the levels of serum creatinine and total bilirubin.ConclusionsExtract of African mistletoe has anti-diabetic and anti-hyperlipidemic effects in STZ-diabetic rats. AM may find clinical application in the amelioration of diabetes-induced lipid disorders.     

Ulcer healing properties of different extracts of Origanum majorana in streptozotocin-nicotinamide induced diabetic rats

ObjectiveThe aim of the present investigation was to evaluate the ulcer healing properties of different extracts of Origannum majorana, viz., hydrodistilled volatile oil (OMO), methanolic (OMM) and aqueous extract (OMW) in streptozotocin-nicotinamide induced diabetic rats.MethodsAll the extracts were administered in different doses (100, 200 and 400 mg/kg, p.o.) to investigate the ulcer healing potential. Streptozotocin (STZ; 65 mg/kg, i.p.) along with nicotinamide (120 mg/kg, i.p.) was used to induce non-insulin dependent diabetes mellitus in rats. Aspirin (200 mg/kg, i.p.) was administered for initial 7 d to induce gastric ulcerations in the diabetic rats. Various biochemical markers of blood and tissue origin were estimated to compare the ulcer healing potential of these extracts.ResultsThe OMO and OMM exhibited dose dependent significant (P<0.01) ulcer healing property than the OMW. Additionally, the antidiabetic property of OMO and OMM was better than OMW.ConclusionThe OMO and OMM of Origanum majorana leaves can prove to be beneficial in the concomitant treatment of gastric ulcers and diabetes.     

Attenuation of oxidative stress and hepatic damage by some fermented tropical legume condiment diets in streptozotocin-induced diabetes in rats

ObjectiveTo investigate the modulatory effect of fermented legume condiments diet on oxidative stress in streptozotocin (STZ) induced diabetic rats.MethodsAdult male Wistar rats were randomly divided into six groups with six animals in each group. Diabetes was induced by intraperitoneal injection of STZ (35 mg/kg b.w.). After being confirmed diabetic, the rats were fed with fermented Bambara groundnut, Locust bean and Soybean diets for 14 days. The plasma was obtained after 14-day treatment and analyzed for hepatic damage marker enzymes (AST, ALT and ALP) and in vivo antioxidant indices.ResultsThe diabetic untreated rats showed elevated (P<0.05) levels of AST, ALT, ALP and malondialdehyde with reduced activities of glutathione^?S^?transferase, catalase as well as plasma reduced glutathione, vitamin C and total protein content. However, treatment of diabetic rats with fermented legume condiments diets for 14 days significantly (P<0.05) reversed the above parameters towards normalcy, suggesting their modulation of oxidative stress, which may be due to their high phenolic content and antioxidant capacity.ConclusionsThe attenuation of oxidative stress and protection of hepatic tissue damage by the legume condiment diets in STZ induced diabetic rats compare favourably with that of metformin, a well known oral hypoglycemic drug.     

Antidiabetic effects of sage (Salvia officinalis L.) leaves in normal and streptozotocin-induced diabetic rats

BackgroundSage (Salvia officinalis L.) has a wide range of biological activities, such as anti-oxidative properties, anti-bacterial, hypoglycemic, anti-inflammatory, fungistatic, virustatic, astringent, eupeptic and anti-hydrotic effects. This study was designed to examine the antidiabetic effect of sage ethanolic extract in normal and streptozotocin-induced diabetic rats.MethodsOral administration of sage extract (0.1, 0.2, and 0.4 g/kg body weight) and glibenclamide (600 μg/kg) for 14 days on the level of serum glucose, triglycerides, total cholesterol, urea, uric acid, creatinine, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in normal and streptozotocin-induced diabetic rats were evaluated.ResultsOral administration of 0.2 and 0.4 g/kg body wt. of the sage extract for 14 days exhibited a significant reduction in serum glucose, triglycerides, total cholesterol, urea, uric acid, creatinine, AST, ALT and increased plasma insulin in streptozotocin-induced diabetic rats but not in normal rats. Glibenclamide was used as reference and showed similar antidiabetic effect.ConclusionsIt is concluded that the traditional use of S. officinalis as an antidiabetic agent is justified and that extracts from this plant show a dose-dependent activity which is comparable to the standard antidiabetic drug glibenclamide.     

Potent hypoglycaemic activity of the aqueous extract of Chamaemelum nobile in normal and streptozotocin-induced diabetic rats

The purpose of this study was to investigate the effect of both a single dose and daily oral administration for 15 days of the aqueous extract of the aerial part of Chamaemelum nobile (C. nobile) at a dose of 20mg/kg body weight on blood glucose concentrations and basal insulin levels in normal and streptozotocin-induced diabetic rats (STZ). Single oral administration of C. nobile aqueous extract reduced blood glucose levels from 6.0 +/- 0.3 mmol/l to 4.9 +/- 0.09 mmol/l (P < 0.05) 6h after administration in normal rats and from 21.1 +/- 1.3 mmol/l to 14.5 +/- 0.9 mmol/l (P < 0.001) in STZ diabetic rats. Furthermore, blood glucose levels were decreased from 6.1 +/- 0.06 mmol/l to 4.6 +/- 0.17 mmol/l (P < 0.01) and from 21.1 +/- 1.31 mmol/l to 13.7 +/- 0.9 mmol/l (P < 0.01) in normal and STZ diabetic rats, respectively, after 15 days of treatment. Basal plasma insulin concentrations remain unchanged after treatment in both normal and STZ diabetic rats so the mechanism of this pharmacological activity seems to be independent of insulin secretion. We conclude that the aqueous extract of C. nobile exhibits a significant hypoglycaemic effect in normal and STZ diabetic rats without affecting basal plasma insulin concentrations and support, therefore, its traditional use by the Moroccan population.     

Rhinacanthus nasutus – Its protective role in oxidative stress and antioxidant status in streptozotocin induced diabetic rats

ObjectiveTo find out the protective action of methanolic extract of Rhinacanthus nasutus (R. nasutus) on lipid peroxidation (LPO) activities and enzymatic antioxidants of liver in streptozotocin (STZ) induced diabetic rats.MethodsExperimental diabetes was induced by a single dose of STZ (50 mg/kg) through intraperitoneal injection. The oxidative stress was measured by tissue LPO level and by enzymatic activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) in liver.ResultsThe raise in LPO levels with reduction in enzymatic activities was the outstanding features observed in diabetic control rats. Administration of R. nasutus (200 mg/kg body weight per day) for 30 days caused a significant reduction in LPO level in STZ induced diabetic rats (group IV) when compared with diabetic control rats (group III). Moreover,R. nasutus treated diabetic rats (group IV) showed significant increase in the activities of enzymatic antioxidants when compared to diabetic control rats (group III).ConclusionThe results obtained specify the ameliorating effects of R. nasutus in the role of oxidative stress created in the experimental diabetic rats.     

Evaluation of antidiabetic property of Andrographis paniculata powder in high fat and sucrose-induced type-2 diabetic adult male rat

ObjectiveTo evaluate the antidiabetic effect of the aerial part of Andrographis paniculata (A. paniculata) powder (500 mg/kg body weight) in high fat and sucrose-induced type-2 diabetic rat model.MethodsThe fasting blood glucose, oral glucose tolerance test, serum insulin, lipid profile, mRNA and protein levels of insulin signaling molecules, 14C-2 deoxy glucose uptake and 14C glucose oxidation in liver were checked.ResultsIn the type-2 diabetes-induced group, the fasting blood glucose, oral glucose tolerance, serum insulin, lipid profile, glucose uptake and oxidation, Akt and glucose transporter 2 mRNA, insulin receptor and glucose transporter 2 protein (both cytosolic and plasma membrane) and phosphorylation of insulin receptor substrate 1 and Akt were impaired. A. paniculata was able to successfully reinstate this impairment. In addition to this, A. paniculata did not cause a hypoglycemic condition in normal rat, affirming its activity in hyperglycemic state alone.ConclusionsA. paniculata possesses significant antidiabetic and antihyperlipidemic activities in high fat and sucrose-induced type-2 diabetic rat and the molecular actions at the level of insulin signaling molecules in liver reinforce it.