Antidiabetic and antioxidant activities of Nypa fruticans Wurmb. vinegar sample from Malaysia

Objective: To study the antidiabetic and antioxidant activities of nipa palm vinegar(NPV) used in traditional Malay medicine for treating diabetes. Methods: NPV was extracted using liquid-liquid extraction method and the obtained samples were subjected to antidiabetic studies using normal and streptozotocin-induced diabetic rat models whereas antidoxidant activities were investigated via in vitro antioxidant tests namely 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azinobis-3-ethylbenzothiozoline-6-sulfonic acid free radicals scavenging activities and the reducing power assay. Results: Single administration of NPV and its extracts were not effective in both normal and diabetic rats. In intraperitoneal glucose tolerance test, NPV and its aqueous extract showed significant blood glucose lowering effect. In the sub-acute study, compared with the diabetic control, aqueous extract of NPV showed the most notable blood glucose lowering effect(56.6%) and a significant improvement in serum insulin levels(79.8%, P0.05). To assess NPV's antioxidant activity, three in vitro antioxidant tests were employed: 2,2-diphenyl-1-picryhydrazyl and 2,2'-azinobis-3-ethylbenzothiozoline-6-sulfonic acid free radical-scavenging assays, and the reducing power assay. Ethyl acetate extract had the greatest antioxidant potential and content of phenolic and flavonoid compounds. A linear positive correlation between the antioxidant parameters was observed. Chemical profiling analysis of aqueous extract of NPV revealed the presence of acetic acid(35.25%), the main active constituent which significantly contributed to the observed antidiabetic activity. Conclusions: Aqueous extract of NPV possesses antihyperglycaemic activities comparable to the metformin, while the ethyl acetate extract precipitated significant antioxidant effects attributable to its high phenolic content. These findings suggest that antioxidant compounds of NPV do not contribute much towards the overall observed antidiabetic effect.     

Hypoglycemic activity of Hemidesmus indicus R. Br. on streptozotocin-induced diabetic rats

OBJECTIVE:

To evaluate the antidiabetic activity of an aqueous extract of the roots of Hemidesmus indicus on blood glucose, serum electrolytes, serum marker enzymes, liver microsomal P-450 enzymes, and lipid peroxidation in the liver and kidney of streptozotocin-induced diabetic rats.

MATERIALS AND METHODS:

Effect of H. indicus extract on blood glucose was studied with fed, fasted and glucose-loaded diabetic and nondiabetic rat models. The effect of the extract on serum electrolytes, serum levels of key glucose metabolizing enzymes, hepatic microsomal protein and hepatic cytochrome P-450-dependent mono-oxygenase enzyme systems and lipid peroxidation in the liver and kidney of diabetic rats. One way analysis of variance and Duncan''s multiple range test was used for statistical analysis.

RESULTS:

Oral administration of H. indicus aqueous extract to fed, fasted and glucose-loaded diabetic rats decreased blood glucose level significantly at 5 h and restored serum electrolytes, glycolytic enzymes and hepatic cytochrome P-450-dependent enzyme systems by preventing the formation of liver and kidney lipid peroxides at the end of 12 weeks of the study period.

CONCLUSION:

From the studies, it can be concluded that the aqueous extract of the roots of H. indicus at a dosage of 500 mg/kg/day exhibits significant antidiabetic activity. It restores the concentrations of electrolytes, glucose metabolizing enzymes, hepatic microsomal protein and hepatic cytochrome P-450-dependent mono-oxygenase enzyme systems to near normal level and also corrects the related metabolic alterations in experimentally induced diabetic rats. H. indicus administration also decreased liver and kidney lipid peroxidation products. On the basis of our findings, H. indicus could be used as an antidiabetic and antioxidant agent for the prevention and treatment of diabetes mellitus.     

The antidiabetic effect of Geigeria alata is mediated by enhanced insulin secretion, modulation of β-cell function, and improvement of antioxidant activity in streptozotocin-induced diabetic rats

In Sudanese folk medicine, Geigeria alata roots have been used for the management of diabetes for a long time. However, its antidiabetic activity is unreported. In this study, G. alata methanolic extract was tested for its antidiabetic, antioxidant, and β-cell modulatory effects in a streptozotocin-induced diabetic rat model. In this model of diabetic rats, the oral glucose tolerance test with G. alata extract at 125, 250, and 500?mg/kg doses revealed the efficacy of the 250?mg/kg dose in improving glucose tolerance comparable to the standard drug glibenclamide. Diabetic rats were treated with a 250?mg/kg dose of G. alata extract orally for 2?h (acute) or 14 days (chronic). In the case of acute treatment, the extract lowered blood glucose levels significantly at 120?min both in nondiabetic and diabetic rats. Chronic treatment of diabetic rats with 250?mg/kg of G. alata extract resulted in a significant decrease in blood glucose level closer to that of nondiabetic rats. Interestingly, increased serum insulin, improved β-cell function, and antioxidant status were observed in G. alata-treated diabetic rats. G. alata also showed strong antioxidant and α-glucosidase inhibitory activities in in vitro assays. These data show direct evidence that G. alata has antidiabetic activity and suggest that the antidiabetic activity is due to enhanced insulin secretion, modulation of β-cell function, and improvement of antioxidant status.     

Evaluation of antidiabetic and antioxidant activity of Moringa oleifera in experimental diabetes

Background: Moringa oleifera, a widely cultivated species in India, is an exceptionally nutritious vegetable with a variety of potential uses in treating rheumatism, venomous bites, and microbial infections. In the present study, we investigated the antidiabetic and antioxidant effects of methanol extracts of M. oleifera pods (MOMtE) in streptozotocin (STZ)‐induced diabetic albino rats. Methods: Diabetic rats were treated with 150 or 300 mg/kg MOMtE for 21 days and the antidiabetic effects of the extract were evaluated by measuring changes in biochemical parameters in the serum and pancreatic tissue. Two phytoconstituents, namely quercetin and kaempferol, were isolated from the MOMtE extract and their structures were determined using nuclear magnetic resonance and infrared spectroscopy. Results: The progression of diabetes was significantly reduced after MOMtE treatment. In treated rats, both doses of MOMtE induced a significant reduction in serum glucose and nitric oxide, with concomitant increases in serum insulin and protein levels. Furthermore, MOMtE treatment increased antioxidant levels in pancreatic tissue, with concomitant decreases in levels of thiobarbituric acid‐reactive substances. Histologic examination of the pancreas from diabetic rats showed degenerative changes in β‐cells; MOMtE treatment significantly reversed the histoarchitectural damage to the islets cells. Conclusion: In conclusion, M. oleifera exerts protective effects against STZ‐induced diabetes. The MOMtE exhibited significant antidiabetic and antioxidant activity and active constituents may be isolated from the extract for evaluation in future clinical studies.     

Hypoglycemic effect of Costus pictus D. Don on alloxan induced type 2 diabetes mellitus in albino rats

ObjectiveTo demonstrate the effect of aqueous extract of Costus pictus (C. pictus) leaves on blood glucose, lipid profile and liver antioxidant enzymes and lipid peroxidation in alloxan induced diabetic rats.MethodsAqueous extract of C. pictus (AECP) leaves was administered orally for 30 days and its effect on blood glucose, lipid profile, hepatic marker enzymes such as serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), serum urea, creatinine, protein and albumin content and liver antioxidant enzymes such as catalase, peroxidase, superoxide dismutase and lipid peroxidation in alloxan induced diabetic rats were examined.ResultsOral administration of aqueous extract of C. pictus leaves to diabetic rats for 30 days significantly reduced the levels of blood glucose, lipid profile, lipid peroxidation, liver marker enzymes, urea, creatinine and increased the levels of antioxidant enzymes.ConclusionsThe aqueous extract of C. pictus leaves controls the blood glucose level, improves lipid metabolism and prevents diabetic complications associated with lipid peroxidation and also maintains the antioxidant enzymes in experimental diabetic rats. Therefore, it can be recommeded for the prevention of diabetes mellitus.     

Antidiabetic, antihyperlipidemic and antioxidant potential of methanol extract of Tectona grandis flowers in streptozotocin induced diabetic rats

ObjectiveTo investigate antidiabetic, antihyperlipidemic and antioxidant activity of methanol extract of Tectona grandis (T. grandis) flowers (METGF) in streptozotocin (STZ) induced diabetic rats to supports its traditional use.MethodsAcute toxicity study of METGF was carried out in rat to determine its dose for the antidiabetic study. Oral glucose tolerance test (OGTT) was performed to evaluate METGF effect on elevated blood glucose level. Diabetes was induced in rats by administration of STZ (60 mg/kg, ip.) and it was confirmed 72 h after induction. METGF was orally given to the diabetic rats up to 28 days and blood glucose level were estimated each week. On 28 day of the experiment, diabetic rats were sacrificed after the blood collection for the biochemical parameters analysis and liver, kidney was collected to determine antioxidants levels.ResultsIn acute toxicity, METGF did not show toxicity and death up to a dose 2 000 mg/kg in rats. Administration of METGF 100 and 200 mg/kg significantly (P<0.001) reduced blood glucose levels in OGTT and STZ-induced diabetic rats. Both doses of METGF treatment significantly (P<0.001, P<0.01 and P<0.05) increased body weight, serum insulin, haemoglobin (Hb) and total protein levels in diabetic rats. Also, MEGTF treatment reduced elevated glycosylated haemoglobin (HbA1c) and other biochemical parameters levels significantly (P<0.001) in diabetic rats. Altered lipid profiles and antioxidants levels were reversed to near normal in diabetic rats treated with METGF.ConclusionsThese results concluded that METGF possesses antidiabetic, antihyperglycemic and antioxidant activity which supports its traditional use.     

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.     

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 hypolipidaemic effects of a methanol/methylene-chloride extract of Laportea ovalifolia (Urticaceae), measured in rats with alloxan-induced diabetes

A decoction of the leaves of Laportea ovalifolia is widely used in Cameroon for the treatment of several illnesses, including diabetes mellitus. The antidiabetic and hypolipidaemic effects of a methanol/methylene-chloride extract of the aerial parts of L. ovalifolia have now been investigated, in normal rats and rats with diabetes induced by the intraperitoneal injection of alloxan (at 150 mg/kg bodyweight). In the diabetic rats, 2 weeks of daily, intragastric treatment with the L. ovalifolia extract not only produced a significant reduction in the fasting serum glucose concentrations but also lowered the serum concentrations of total cholesterol, triglycerides, and low-density-lipoprotein cholesterol, lowered the ratio of total cholesterol to high-density-lipoprotein (HDL) cholesterol, and increased the serum concentration of HDL cholesterol. At least in rats with alloxan-induced diabetes, the methanol/methylene-chloride extract of L. ovalifolia therefore appears to possess antidiabetic and hypolipidaemic properties.     

Effect of vitamin E and C supplementation combined with oral antidiabetic therapy on the endothelial dysfunction in the neonatally streptozotocin injected diabetic rat

BACKGROUND: This study investigates the contribution of vitamin supplementation to the efficacy of oral antidiabetic therapy on the reversal of endothelial dysfunction in a model of type-2 diabetes in rat. METHODS: Diabetes was induced by streptozotocin injection to neonatal rats which were breastfed for 4 weeks, then fed 6 weeks with normal food or food supplemented with 2% vitamin E and 4% vitamin C. Some diabetic rats were treated with gliclazide for 6 weeks. Endothelium-dependent and -independent relaxations to acetylcholine and sodium nitroprusside (SNP) were recorded in thoracic aortic rings. Plasma insulin, HbA(1c) and antioxidant vitamins (A, C and E); plasma and aortic malondialdehyde (MDA) levels were determined. RESULTS: Induction of diabetes resulted in decreased body weight and increased blood glucose, plasma insulin and HbA(1c) levels compared to controls. Acetylcholine relaxation was impaired in diabetic aorta, while SNP relaxation remained unchanged. Aortic MDA level was significantly higher, while plasma vitamin levels were lower in diabetic rats. Diminished acetylcholine response, enhanced aortic MDA level and decreased plasma vitamin levels were all restored after gliclazide and/or vitamin therapy. However, vitamin supplementation in control rats significantly impaired acetylcholine relaxations and increased aortic MDA levels. CONCLUSIONS: Apparently, a selective endothelial dysfunction accompanies the imbalance in oxidant/antioxidant status in the type-2 diabetes model of rat and gliclazide and/or vitamin supplementation improves the impairment in diabetic vasculature. However, vitamin supplementation triggers oxidative stress in normal aortic tissue, thereby, leads to endothelial dysfunction; indicating that nutritional extra-supplementation of antioxidant vitamins isn't advisable for normal subjects, although it's beneficial in disease status.     

Gallic acid and p-coumaric acid attenuate type 2 diabetes-induced neurodegeneration in rats

The brain of diabetics revealed deterioration in many regions, especially the hippocampus. Hence, the present study aimed to evaluate the effects of gallic acid and p-coumaric acid against the hippocampal neurodegeneration in type 2 diabetic rats. Adult male albino rats were randomly allocated into four groups: Group 1 served as control ones and others were induced with diabetes. Group 2 considered as diabetic, and groups 3 and 4 were further orally treated with gallic acid (20 mg/kg b.wt./day) and p-coumaric acid (40 mg/kg b.wt./day) for six weeks. Diabetic rats revealed significant elevation in the levels of serum glucose, blood glycosylated hemoglobin and serum tumor necrosis factor-α, while the level of serum insulin was significantly declined. Furthermore, the brain of diabetic rats showed a marked increase in oxidative stress and a decrease of antioxidant parameters as well as upregulation the protein expression of Bax and downregulation the protein expression of Bcl-2 in the hippocampus. Treatment of diabetic rats with gallic acid and p-coumaric acid significantly ameliorated glucose tolerance, diminished the brain oxidative stress and improved antioxidant status, declined inflammation and inhibited apoptosis in the hippocampus. The overall results suggested that gallic acid and p-coumaric acid may inhibit hippocampal neurodegeneration via their potent antioxidant, anti-inflammatory and anti-apoptotic properties. Therefore, both compounds can be recommended as hopeful adjuvant agents against brain neurodegeneration in diabetics.

     

Hypotriglyceridemic and hypocholesterolemic effects of anti-diabetic Momordica charantia (karela) fruit extract in streptozotocin-induced diabetic rats

Momordica charantia (karela) is commonly used as an antidiabetic and antihyperglycemic agent in Asian, Oriental and Latin American countries. This study was undertaken to investigate the effects of long term feeding (10 weeks) of M. charantia fruit extract on blood plasma and tissue lipid profiles in normal and streptozotocin (STZ)-induced Type 1 diabetic rats. The results show that there was a significant (P < 0.05) increase in plasma non-esterified cholesterol, triglycerides and phospholipids in STZ-induced diabetic rats, accompanied by a decrease in high density lipoprotein (HDL)-cholesterol. A moderate increase in plasma (LPO) product, malonedialdehyde (MDA), and about two-fold increase in kidney LPO was also observed in STZ-induced diabetic rats. The treatment of diabetic rats with M. charantia fruit extract over a 10-week period returned these levels close to normal. In addition, karela juice also exhibited an inhibitory effect on membrane LPO under in vitro conditions. These results suggest that M. charantia fruit extract exhibits hypolipidemic as well as hypoglycemic effects in the STZ-induced diabetic rat.     

Antidiabetic activity of aqueous leaf extract of Atriplex halimus L. (Chenopodiaceae) in streptozotocin-induced diabetic rats

Objective

To investigate the antidiabetic effect of A. halimus leaf in streptozotocin-induced diabetic rats.

Methods

The aqueous extract of the plant leaf was tested for its efficacy in streptozotocin-induced diabetic rats. The extract was evaluated for its acute and short term general toxicity in male mice and for its antihyperglycemic activity using glucose tolerance test in rats. The aqueous extract was subjected to phytochemical screening and determination of total phenolic contents.

Results

The statistical data indicated the significant increase in the body weight and decrease in the blood glucose and hepatic levels. The total protein level was significantly increased when treated with the extract.

Conclusions

These results suggest that the aqueous leaf extract of A. halimus has beneficial effects in reducing the elevated blood glucose level and hepatic levels in streptozotocin-induced diabetic rats.     

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.     

In vivo anti-hyperglycemic and antioxidant potentials of ethanolic extract from tecomella undulata

ABSTRACT: This study was undergone to evaluate the in-vivo anti-hyperglycemic and antioxidant potential of ethanolic extract of leaves of Tecomella undulata Seem. on streptozotocinnicotinamide induced type 2 diabetic rats. Type 2 diabetes was induced by single intraperitoneal injection (i.p.) of 60 mg/kg streptozotocin, 15 minutes after the i.p administration of 110 mg/kg body weight of nicotinamide. The extract has shown significant blood glucose lowering effect in the oral glucose tolerance test (OGTT). The blood glucose level, cholesterol, glycogen contents, glycosylated hemoglobin, and antioxidant parameters (Malondialdehyde and Glutathione level) were estimated from the blood plasma by using standard kits to demonstrate the hypoglycemic and antioxidant effect in treated animals. The data showed that the extract have significant influence on the above biochemical parameters. Thus ethanolic fraction of the plant Tecomella undulata can be used as new candidate for antihyperglycemic and antioxidant.     

Synergistic antidiabetic activities of zinc, cyclo (his-pro), and arachidonic acid

Previous studies have already shown that prostate extract (PE) has antidiabetic activity when given to animals and humans. In this study, we explore whether this antidiabetic activity is related to the high concentrations of zinc, cyclo (his-pro) (CHP), and the prostaglandin precursor, arachidonic acid (AA), in prostate tissue. When streptozotocin-induced diabetic rats were given drinking water containing 10 mg/L zinc and 100 mg/L PE for 3 weeks, fasting blood glucose levels and glucose clearance rates, but not plasma insulin levels, were significantly lower than at pretreatment. In subsequent experiments, blood glucose levels in rats given PE for 3 weeks were significantly lower than in rats given distilled water or 10 mg/L zinc alone. However, in rats given 100 mg/L CHP with zinc, blood glucose levels were also lower than in rats given PE alone. Time-course studies in diabetic rats given drinking water containing 20 mg/L Zn, 20 mg/L L-histidine, and 10 mg/L CHP showed that blood glucose levels dropped 209 +/- 53 mg/dL in 1 day and stayed low for 2 weeks. When CHP was replaced with 100 mg AA/L, blood glucose levels dropped 230 +/- 64 mg/dL in 5 days, but returned to the original values 11 days later. Growth rate improved and water consumption decreased significantly in CHP- and AA-treated diabetic rats. High intake of L-histidine and testosterone increased blood glucose concentrations in diabetic rats. To determine optimal dosages of CHP and AA, we gave rats drinking water containing 10 mg/L Zn and 0.5 mg/L L-histidine with various concentrations of CHP or AA. The most effective doses for reducing blood glucose levels were 0.32 mg CHP/kg/day and 11 mg AA/kg/day. These data suggest that the active antidiabetic ingredients in the PE are CHP, zinc, and AA or its precursors.     

Prevention of diabetes-induced myocardial dysfunction in rats using the juice of the Emblica officinalis fruit

Normalization of hyperglycemia, hyperlipidemia and oxidative stress is an important objective in preventing diabetes-induced cardiac dysfunction. The present study investigated the effects of the fruit juice obtained from Emblica officinalis on myocardial dysfunction in diabetic rats. Diabetes was induced by streptozotocin (STZ), and the rats were treated with E officinalis fruit juice for eight weeks. Injection of STZ produced loss of body weight, polydypsia, polyphagia, hyperglycemia, hypoinsulinemia and dyslipidemia. It also produced hypertension, bradycardia, hypertrophy and myocardial functional alterations associated with an increase in serum lactate dehydrogenase and creatinine kinase-MB levels. Treatment with the fruit juice not only prevented STZ-induced loss of body weight, increases in water and food intake, increases in serum glucose levels and disturbed lipid profile, but also an increase in serum lactate dehydrogenase and creatinine kinase-MB levels, and increased myocardial hypertrophy and cardiomyopathy. There was an increase in the area under the curve (AUC) for glucose, and a decrease in AUC_insulin was observed in diabetic rats; treatment decreased AUC_glucose but not AUC_insulin or hyperinsulinemia. There was a decrease in antioxidant enzyme levels (in superoxide dismutase, reduced glutathione and catalase) in diabetic hearts, which could be improved by treatment with fruit juice. The present data suggest that fruit juice may be beneficial for the treatment of myocardial damage associated with type 1 diabetes mellitus. The activity of E officinalis fruit juice can be attributed to the concentration of polyphenol present.     

Influence of mulberry (Morus indica L.) leaves on antioxidants and antioxidant enzymes in STZ-diabetic rats

To assess the influence of mulberry (Morus indica L.) leaves on antioxidants and antioxidant enzymes in STZ- diabetic rats as the leaves of mulberry (Morus indica L.) of Moraceae, are reported to be rich in a no. of bioactive principles i.e. antioxidant vitamins, flavonoids and moracins that can fight against oxidative stress in diabetes. STZ-diabetic rats were treated with dried mulberry leaves incorporated in the feed at 25 % level (as per dose response) for 8 weeks in standard experimental conditions in comparison with diabetic glibenclamide–treated and diabetic control rats. At the end of experimental period, fasting blood glucose, serum non-enzymatic antioxidants, hepatic lipid peroxidation and antioxidant enzymes were assayed in all the experimental groups. Hyperglycemia, a 274 % (P?<?0.01) rise in fasting blood glucose and increased oxidative stress as shown by a two fold increase in lipid peroxidation in hepatic tissue, decreased serum non enzymatic antioxidants viz. vit.C (51 %) and E (47 %), significantly decreased activities of hepatic antioxidant enzymes such as glucose-6-phosphate dehydrogenase (43 %), glutathione peroxidase (41 %) and superoxide dismutase (44 %) and significantly increased activity of catalase (39 %) in STZ-diabetic rats were ameliorated by mulberry leaves which is evidenced by significant fall in fasting glucose, and lipid peroxidation, rise in antioxidants as well as the activities of defense enzymes and decrease in the activity of catalase while the antidiabetic drug, glibenclamide showed lesser effects than mulberry leaves. Mulberry leaves protected STZ-diabetic rats against oxidative stress by improving antioxidants and the activities of defense enzymes and controlling hyperglycemia and lipid peroxidation in a better way than the drug.     

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.     

Hesperidin and naringin attenuate hyperglycemia-mediated oxidative stress and proinflammatory cytokine production in high fat fed/streptozotocin-induced type 2 diabetic rats

Abnormal regulation of glucose and impaired carbohydrate utilization that result from a defective or deficient insulin are the key pathogenic events in type 2 diabetes mellitus (T2DM). The present study was hypothesized to investigate the beneficial effects of hesperidin and naringin on hyperglycemia-induced oxidative damage in HFD/STZ-induced diabetic rats. Diabetes was induced by feeding rats with an HFD for 2 weeks followed by an intraperitoneal injection of STZ (35 mg/kg body weight). An oral dose of 50 mg/kg hesperidin or naringin was daily given for 4 weeks after diabetes induction. At the end of the experimental period, blood was obtained from jugular vein and livers were rapidly excised and homogenized for biochemical assays. In the diabetic control group, levels of glucose, glycosylated hemoglobin (HbA1c%), MDA, NO, TNF-α and IL-6 were significantly increased, while serum insulin, GSH, vitamin C, and vitamin E levels were decreased. Both hesperidin and naringin administration significantly reversed these alterations. Moreover, supplementation with either compound significantly ameliorated serum and liver MDA, NO and glutathione, and liver antioxidant enzymes. Although detailed studies are required for the evaluation of the exact mechanism of the ameliorative effects of hesperidin and naringin against diabetic complications, these preliminary experimental findings demonstrate that both hesperidin and naringin exhibit antidiabetic effects in a rat model of T2DM by potentiating the antioxidant defense system and suppressing proinflammatory cytokine production.