Antidiabetic Properties of Bidens pilosa and Its Polyacetylenic Compounds for Management of Diabetes: Systematic Review

Bidens pilosa is a member of the Asteraceae family that is widely distributed across the tropics. It has been utilized by different communities both as food and medicinal herb. This plant and its polyacetylenic compounds hold potential as a natural antidiabetic intervention that can be used to combat this global public health problem. Bioactive compounds found in this plant constitute promising interventions for combating obesity which is a major risk factor for the development of type 2 diabetes. These phytocompounds can work independently or synergistically to modulate appetite, lipase activity, adipogenesis and adipocyte apoptosis. However, the efficacy, mode of action and scope of management of diabetes by these compounds remains elusive. The current review aims to summarize data on efficacy in the management of diabetes, an antidiabetic candidate polyacetylenic compound and possible biological activities as an antidiabetic agent from the available literature. Much emphasis has been directed to cytopiloyne as a representative of polyacetylenic compounds extracted from Bidens pilosa and its activity on diabetic animal models. The majority of the studies conducted on animal models described antidiabetic mechanisms that range from hypoglycemic to secretagogue activity of cytopiloyne in a dose-dependent manner. A clinical trial pilot indicated improved glycemic control of Bidens pilosa formulation among diabetic patients in the study. Bidens pilosa and its compounds are highly potent antidiabetic agent(s) that should be graduated to an intervention for management of diabetes through pre-clinical and clinical trials to elucidate its efficacy and safety.

Role of antidiabetic agents in type 2 diabetes patients with chronic kidney disease

Insulin resistance is a condition in which the target tissues have a decreased response to insulin signaling,resulting in glucose uptake defect,and an increased blood sugar level.Pancreatic beta cells thus enhance insulin production to compensate.This situation may cause further beta cell dysfunction and failure,which can lead diabetes mellitus(DM).Insulin resistance is thus an important cause of the development of type 2 DM.Insulin resistance has also been found to have a strong relationship with cardiovascular disease and is common in chronic kidney disease(CKD)patients.The mechanisms of insulin resistance in CKD are complex and multifactorial.They include physical inactivity,inflammation and oxidative stress,metabolic acidosis,vitamin D deficiency,adipose tissue dysfun-ction,uremic toxins,and renin-angiotensin-aldosterone system activation.Currently,available anti-diabetic agents,such as biguanides,sulfonylureas,thiazolidinediones,alfa-glucosidase inhibitors,glucagon-like peptide-1-based agents,and sodium-glucose co-transporter-2 inhibitors,have different effects on insulin resistance.In this short review,we describe the potential mechanisms of insulin resistance in CKD patients.We also review the interaction of currently available anti-diabetic medications with insulin resistance.

Design of New Thiadiazole Derivatives with Improved Antidiabetic Activity

Diabetes is a serious, long-term (or chronic) disease that occurs when a person’s blood sugar levels are high because their body cannot produce enough insulin, or does not produce enough insulin or that it cannot effectively use the insulin it produces. According to the literature, this disease has several causes, but certain types of diabetes such as type 2 diabetes are most closely linked to a metabolic disorder due to abdominal obesity. Thus, the number of individuals with type 2 diabetes is increasing. It is with this in mind that we work to improve human health. The aim of this study is to design new derivatives of 1,3,4-thiadiazole with improved antidiabetic activity by the mathematical model of multiple linear regression (MLR) established previously. The analysis of the effect on the substituents influencing the antidiabetic activity, fourteen (14) new molecules coded CDTH were generated and presenting values of the potential of inhibitory concentration higher than that of the base compound (pIC50 = 2.526). But thirteen (13) of these new compounds belong to the domain of applicability of the MLR model established previously. In addition, the thermodynamic quantities of formation formed at 298K have been calculated. Lipinski’s rule and pharmacokinetic properties proved that five (5) (TH4, TH9, TH10, TH13 and TH14) new molecules can be used as diabetes medicine.

Astragalus adscendens extract shows antidiabetic effects through controlling oxidative stress,inflammation and apoptosis in streptozotocin-induced diabetic rats

Objective:To assess the effect of oral treatment of methanolic extract of the aerial parts of Astragalus adscendens in streptozotocin-induced diabetic rats.Methods:In order to induce diabetes,rats intraperitoneally received streptozotocin at 65 mg/kg.Sixty adult male Wistar rats were allocated into six groups(10 rats per each)including the healthy control group,the diabetic group as well as the diabetic group treated with Astragalus adscendens methanolic extract at 50,100,and 200 mg/kg per day or glibenclamide(0.6 mg/kg/day)for 28 d.The effects of Astragalus adscendens methanolic extract on the levels of glucose,insulin,alanine aminotransferase,alkaline phosphatase,aspartate aminotransferase,bilirubin,creatinine,urea,uric acid,total protein,albumin,triglyceride,cholesterol,α-amylase,oxidant/antioxidant enzymes,and inflammatory cytokines were evaluated.Real time-PCR was also used for measuring the gene expression of caspase-3,Bcl2,and Bax.Results:The levels of glucose,cholesterol,triglyceride,creatinine,urea,uric acid,alanine aminotransferase,aspartate aminotransferase,alkaline phosphatase,bilirubin,and malondialdehyde considerably declined(P<0.001)in diabetic rats after treatment with Astragalus adscendens methanolic extract especially at a dose of 200 mg/kg.In addition,treatment with Astragalus adscendens methanolic extract noticeably increased the level of insulin,total protein,and albumin as well as improved the activities of catalase,glutathione peroxidase,and superoxide dismutase,as well as the expression levels of TNF-α,IL-1β,caspase-3,Bcl2 and Bax(P<0.001)compared to the diabetic control group.The extract also inhibitedα-amylase in a dose-dependent manner with an IC_(50)value of 19.6μg/mL.Conclusions:Astragalus adscendens methanolic extract shows potent antidiabetic,anti-inflammatory,anti-apoptotic,and antioxidant effects in diabetic rats.However,more studies are needed to verify the underlying mechanism of the effect of this plant extract and test its efficacy in clinical trials.

An overview on antidiabetic medicinal plants having insulin mimetic property

Diabetes mellitus is one of the common metabolic disorders acquiring around 2.8%of the world's population and is anticipated to cross 5.4%by the year 2025.Since long back herbal medicines have been the highly esteemed source of medicine therefore,they have become a growing part of modern,high-tech medicine.In view of the above aspects the present review provides profiles of plants(65 species) with hypoglycaemic properties,available through literature source from various database with proper categorization according to the parts used,mode of reduction in blood glucose(insulinomimetic or insulin secretagugues activity) and active phyloconsliluents having insulin mimetics activity.From the review it was suggested that,plant showing hypoglycemic potential mainly belongs to the family Leguminoseae,Lamiaceae,Liliaceae,Cucurbitaceae, Asteraceae,Moraceae,Rosaceae and Araliaceae.The most active plants are Allium sativum. Gymnema sylvestre,Citrullus colocynthis,Trigonella foenum greacum,Momordica charantia and Ficuts bengalensis.The review describes some new bioactive drugs and isolated compounds from plants such as roseoside,epigallocatechin gallate,beta-pyrazol-1-ylalanine,cinchonain Ib,leucocyandin 3-O-beta-d-galactosyl cellobioside,leucopelargonidin-3- O-alpha-L rhamuoside,glycyrrhetinic acid,dehydrotrametenolic acid,strictinin,isostrictinin,pedunculagin, epicatechin and christinin-A showing significant insulinomimetic and antidiabetic activity with more efficacy than conventional hypoglycaemic agents.Thus,from the review majorly,the antidiabetic activity of medicinal plants is attributed to the presence of polyphenols,flavonoida, terpenoids,coumarins and other constituents which show reduction in blood glucose levels.The review also discusses the management aspect of diabetes mellitus using these plants and their active principles.

Antidiabetic and haematological effect of aqueous extract of stem bark of Afzelia africana(Smith) on streptozotocin-induced diabetic Wistar rats

Objective:To investigate the antidiabetic properties of aqueous extract of stem bark of Afzelia africana(A.africana)and its beneficial effect on haematological parameters in streptozotocin induced diabetic rats.Methods:A total of 30 rats including 24 diabetic and 6 normal rats were used for this study.Diabetes was induced in male Wistar rats by intraperitoneal injection of streptozotocin.After being confirmed diabetic,animals were orally treated with distilled water or extracts at 100 or 200 mg/kg body weight daily for 10 days.The haematological parameters including red blood and white blood cells and their functional indices were evaluated in diabetic treated groups compared with the controls.Results:The extract significantly reduced the blood glucose levels while the best result was obtained at 200 mg/kg body weight The feed and water intake in diabetic rats were significantly reduced while weight loss was minimized at both dosages.Similarly,the levels of red blood,white blood cells and their functional indices were significantly improved after extract administration at both doses.Conclusions:It can be concluded that the aqueous extract of bark of A.africana possesses antihyperglycemic properties.In addition,the extract can prevent various complications of diabetes and improve some haematological parameters.Further experimental investigation is needed to exploit its relevant therapeutic effect to substantiate its ethnomedicinal usage.

Antidiabetic activity of alcoholic leaves extract of Alangium lamarckii Thwaites on streptozotocin-nicotinamide induced type 2 diabetic rats

Objective:To investigate antidiabetic potential of alcoholic leaves extract of Alangium lamarekii (A.lamarckii) on streptozotocin-nicotinamide induced type 2 diabetic rats.Methods:Oral glucose tolerance test was done by inducing hyperglycemic state via administration of glucose in water(2 g/kg).Single dose of alcoholic leaves extract of.4.lamarckii(250 and 500 mg/kg,p.o.) were administered to normoglycemic,hyperglycemic rats.Type 2 diabetes was induced by single intraperitoneal injection of nicotinamide(110 mg/kg) followed by streptozotocin(65 mg/kg).The study also included estimations of blood plasma glucose,lipid profile,liver glycogen,body weight and antioxidant status in normal and diabetic rats.Results:Admistration of alcoholic extract of A.lamarekii at two dosage 250 and 500 rag/kg,p.o.did not showed any significant change in blood glucose level of normoglycemic rats(P】0.05).whereas,oral glucose tolerance test depicted reduction in blood glucose level(P【0.05).The streptozotocin-nicotinamide induced diabetic rats, significantly decreased the blood plasma glucose level(P【0.001) comparable to glibenclamide (10 mg/kg),restored the lipid profile and showed improvement in liver glycogen,body weight and antioxidant status in diabetic rats.Conclusions:Present finding demonstrated the significant antidiabetic activity of alcoholic leaves extract of.4.lamarekii.

Antidiabetic activity of methanolic bark extract of Alhizia odoratissima Benth.in alloxan induced diabetic albino mice

Objective:To evaluate the antidiabetic potential of methanolic extract of Albizia odoratissima Benth.bark in alloxan induced diabetic mice.Methods:Group-Ⅰ(normal control) mice received only basal diet without any treatment.In Group-Ⅱ(Diabetic control) mice,diabetes was induced by alloxan(150 mg/kg i.p.) and received only Tween 80.5%v/v in normal saline. Group-Ⅲand Group-Ⅳmice received metformin(10 mg/kg) and gliclazide(10 mg/kg) as standard drugs.Group-ⅤandⅥmice received methanolic bark extract of Albizia odoratissima at doses of 250 and 500 mg/kg body weight p.o.,respectively.Results:The results of the study indicates that Albizia odoratissima bark extract significantly(P【0.01) reduced the blood sugar level.The bark extract also significantly reduced the levels of serum cholesterol,triglycerides, serum glutamic-oxaloacetic transaminase,serum glutamic-pyruvic transaminase,alkaline phosphatase and decreases level of total proteins in alloxan induced diabetic mice.Conclusions: Methanolic extract of Albizia odoratissima has protective effects on the protection of vital tissues(pancreas,kidney,liver,heart and spleen),thereby reducing the causation of diabetes in experimental animals.

Effects of antidiabetic drugs on epicardial fat

Epicardial adipose tissue is defined as a deposit of adipocytes with pathophysiological properties similar to those of visceral fat, located in the space between the myocardial muscle and the pericardial sac. When compared with subcutaneous adipose tissue, visceral adipocytes show higher metabolic activity, lipolysis rates, increased insulin resistance along with more steroid hormone receptors. The epicardial adipose tissue interacts with numerous cardiovascular pathways via vasocrine and paracrine signalling comprised of pro-and anti-inflammatory cytokines excretion. Both the physiological differences be-tween the two tissue types, as well as the fact that fat distribution and phenotype, rather than quantity, affect cardiovascular function and metabolic processes, establish epicardial fat as a biomarker for cardiovascular and metabolic syndrome. Numerous studies have underlined an association of altered epicardial fat morphology, type 2 diabetes mellitus(T2 DM) and adverse cardiovascular events. In this review, we explore the prospect of using the epicardial adipose tissue as a therapeutic target in T2 DM and describe the underlying mechanisms by which the antidiabetic drugs affect the pathophysiological processes induced from adipose tissue accumulation and possibly allow for more favourable cardiovascular outcomes though epicardial fat manipulation.

Antidiabetic principles of Loranthus micranthus Linn.parasitic on Persea americana

Objective:To explore antidiabetic principles of the Eastern Nigeria mistletoe,Loranlhus micranthus Linn,parasitic on Persea Americana.Methods:The weakly acidic fraction of the aqueous methanol extract of the leaves of Loranlhus micranthus(Linn.) was isolated and tested for its antidiabetic activities.The isolation of the weakly acidic fraction was carried out following established physico-chemical based procedures.Furthermore,alloxan-induced diabetic rats were treated intraperitoneally(ip) with 250 mg/kg and 400 mg/kg of the weakly acidic fraction, glibenclamide 10 mg/kg(positive control) and 2 mg/kg of 3%v/v tween 20(negative control).The sugar levels of the treated and untreated animals were determined by withdrawing the blood at regular intervals and testing them with an automated glucometer.The phytochemical analysis of the acidic fraction was carried out using standard procedures.Chromatographic techniques were employed in the subsequent isolation and purification of the constituents of the weakly acidic fraction.Results:It was shown that the maximum effect of the weakly acidic fraction was obtained at 24 hours after administration and was found to be statistically comparable with that of the positive control.The phytochemical analysis revealed the presence of steroids,terpenoids, alkaloids,flavonoids,glycosides,carbohydrates,saponins,and acidic compounds in the crude extract and carbohydrates,flavonoids.terpenoids and oil in the weakly acidic fraction.Further purification of the weakly acidic fraction of the methanol extract using thin layer chromatography shows that toluene:methanol:diethyl amine(3:1:1) and chloroform:methanol:diethyl amine (9:1:1) are the best solvent system for the isolation of the various components of the weakly acidic fraction of the crude methanol extract of Loranlhus micranthus.Conclusions:The present study has led to the conclusion that the weakly acidic fraction of the plant under study has the potent antidiabetic activity and that the various components can be isolated using basic chromatographic techniques.

Seasonal variation for the antidiabetic activity of Loranthus micranthus methanol extract

Objective:To determine the season in which the Eastern Nigeria mistletoe,Loranthus micranthus,parasitic on Persea americana possesses optimum antidiabetic activity and to determine the seasonal variation in the constituents.Methods:The antidiabetic activities of the aqueous methanol extracts of the leaves of Eastern Nigeria mistletoe,Loranthus micranthus, harvested in two seasons of the year,the onset of rainy season(April) and the peak of rainy season(July) were compared.The tests were carried out on six(6) groups(A-F) of alloxaninduced diabetic rats.Groups A and B received 200 mg/kg and 400 mg/kg of the April sample extracts respectively while groups C and D received same doses of the July sample extracts. Group E and F which were the positive and negative controls received 10 mg/kg of glibenclamide and 2 ml/kg of 3%tween 20 respectively.The blood glucose levels of the animals were monitored hourly with a glucometer for six hours.The phytochemical analysis of the plant extracts were also carried out by standard procedures.Results:The results showed that group A and B exhibited significant(P【0.05) percentage reduction in the fasting blood sugar(FBS) level of the animals(38.9%and 39.2%respectively) with maximum reduction observed at the 5th and 6th hour respectively compared to glibenclamide(71.3%).Group C showed no significant (P】0.05) FBS reduction(15.9%) while group D exhibited highly significant(P【0.01) reduction (47.5%) with the maximum reduction occurring after 6 hours.The phytochemical analysis of the crude methanol extracts revealed the presence of carbohydrates,glycosides,saponins, tannins,flavonoids,steroids,terpenoids,acidic compounds,resins and oils.These were present in different proportions in both seasons.Conclusions:This study shows that there is a seasonal, dose-dependent variation in the chemical composition viz-a-viz the antidiabetic activity of the plant under study.This activity is highest at the peak of the rainy season.

Antidiabetic effect of Merremia emarginata Burm.F.in streptozotocin induced diabetic rats

Objective:To investigate the antidiabetic property of Merremia emarginata(M.emarginata) Burm.F.plant in streptozotocin induced diabetic rats.Methods:The dose dependent effects of 28 days oral treatment with methanol extract(100,200 and 400 mg/kg) from the plant oi M.emarginata on blood glucose level,body weight,insulin,total hemoglobin,glycosylated haemoglobin(HbA1C),total protein,serum urea,serum creatinine and carbohydrate metabolizing enzymes were evaluated in streptozotocin induced diabetic rats.Histology of pancreas was also studied.Results:A significant decrease in blood glucose,serum urea and serum creatinine and significant increase in body weight,insulin and protein level were observed in diabetic rats treated with M.emarginata.Treatment with M.emarginata resulted in a significant reduction of HbAlC and an increase in total hemoglobin level.The activities of carbohydrate metabolizing enzymes such as hexokinase were significantly increased whereas glucose-6phosphatase,fructose-1,6-bisphosphatase were significantly decreased by the administration of M.emarginata in diabetic rats.Histology of diabetic rats treated with M.emarginata showed the pancreatic β-cells regeneration.Conclusions:These findings suggest that M.emarginata has potent antidiabetic activity in streptozotocin induced diabetic rats.

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

Objective:To 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).Methods:Blood 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 Results:Daily 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. Conclusions:D.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.

Antidiabetic and hypolipidemic activities of Kigelia pinnata flowers extract in streptozotocin induced diabetic rats

Objective:To evaluate antidiabetic and hypolipidemic activities of Kigelia pinnata rnethanolic(lowers extract in slreplozolocin(STZ) induced diabetic W islar rat.Methods.Rats were made diabetic by a single dose of STZ at 60 mg/kg body weight i.p.The blood glucose level was checked before and 72 h after STZ injection to confirm the development ot diabetes.The flower extract and glibenclamide were administered orally at the doses of 250 and 500 mg/kg body weight for 21 days.Results:Daily oral treatment with the extract and standard drug for 21 days significantly reduced blood glucose,serum cholesterol and triglycerides levels.High density lipoprotein-cholesterol level was found to be improved(P<0.01) as compared to diabetic control group.Conclusions:It is concluded that Kigellia pinnata flowers extract have significant antidiabetic and hypolipidemic effect.

Antidiabetic and anti-lipemic effects of Cassia siamea leaves extract in streptozotocin induced diabetic rats

Objective:To investigate the antidiabetic and anti-lipemic effects of Cassia siamea methanolic leaves extract.Methods:The antidiabetic study was performed by measuring blood glucose level with elegance glucometer at weekly intervals i.e.0,7,14 and 21 in normal and streptozotocin induced diabetic rats.Total cholesterol,triglyceride and HDL-cholesterol were determined in normal and streptozotocin induces diabetic rats by autoanalyser.Glibenclamide was used as a reference drug at a dose of 10 mg/kg.Results:After the oral administration of extracts at doses of 250 mg/kg and 500 mg/kg for three weeks,blood glucose levels and body weights were significantly improved(P【0.01).Daily oral treatment with the extract also resulted in significantly reduction of serum cholesterol and triglycerides.HDL-cholesterol level was found to be improved to(P【0.01).Conclusions:The Cassia siamea leaf extract is useful in controlling blood glucose level as well as improving lipid metabolism and body weight in rats with induced diabetes.

Metabolite profiling and antidiabetic attributes of ultrasonicated leaf extracts of Conocarpus lancifolius

Objective:To profile the secondary metabolites and to evaluate the antidiabetic potential of hydroethanolic leaf extracts of Conocarpus lancifolius.Methods:The various hydroethanolic extracts of Conocarpus lancifolius leaf were prepared by ultrasonication assisted freezedrying.Total phenolic contents,flavonoid contents,antioxidant activity,α-glucosidase andα-amylase inhibitions of leaf extracts were determined.The metabolite profiling was accomplished by UHPLC-Q-TOF-MS/MS analysis.The antidiabetic assessment of the most potent extract was carried out by measuring the hypoglycemic and hypolipidemic effect in the high fat diet-fed diabetic albino mice.The blood glucose level,haemoglobin,total cholesterol,high-density lipoproteins(HDL)and low-density lipoproteins(LDL)were determined.Results:The 60%ethanolic extract exhibited the highest phenolic and flavonoid contents of(349.39±2.13)mg GAE/g dry extract and(116.95±2.34)mg RE/g dry extracts,respectively,and the highest DPPH scavenging activity with an IC50 value of(32.87±1.11)μg/mL.The IC50 values forα-glucosidase andα-amylase inhibitions were(38.64±0.93)μg/mL and(44.80±1.57)μg/mL,respectively.UHPLC-Q-TOF-MS/MS analysis confirmed the presence of gallic acid,ellagic acid,corilagin,kaempherol-3-O-rutinoside,caffeic acid derivative,isorhamnetin and galloyl derivatives in the 60%ethanolic extract.Plant extract at a dose of 450 mg/kg body weight reduced blood glucose level,total cholesterol,LDL and HDL,and increased haemoglobin in alloxan-induced diabetic mice,Conclusions:Conocarpus lancifolius leaves are proved as a good source of biologically functional metabolites and possess antidiabetic activity which may be further explored to treat diabetes.

Antidiabetic and antioxidant activities of red seaweed Laurencia dendroidea

Objective:To investigate antidiabetic and antioxidant activities of the extract and fractions from Vietnamese red seaweed Laurencia dendroidea.Methods:The seaweed Laurencia dendroidea was extracted by using microwave-assisted extraction method in 80%methanol.The seaweed extract was then fractionated using different solvents(n-hexane,chloroform,ethyl acetate,butanol and water).These obtained fractions were evaluated forα-glucosidase inhibitory and antioxidant activities.Antioxidant activities were tested using DPPH,nitric oxide radical scavenging and metal chelating assays.The enzyme inhibition mode was determined using Lineweaver-Burk plot.For acidic and thermal stabilities,the ethyl acetate fraction was treated at pH 2.0 and 100℃,respectively.The residual inhibitory activity of the fraction was calculated based on the initial inhibitory activity.For in vivo antidiabetic activity,mice were divided into four groups,including normal control,diabetic control,diabetic mice treated with ethyl acetate fraction and diabetic mice treated with gliclazide.Blood glucose level of treated mice during acute and prolonged treatments was measured.To evaluate the toxicity of the ethyl acetate fraction,the body weight changes and activities of liver function enzymes(aspartate transaminase,alanine transaminase and gammaglutamyl transferase)were carried out.Results:The extract of Laurencia dendroidea showed strongα-glucosidase inhibitory and DPPH radical scavenging activities.Methanolic concentrations affected bothα-glucosidase inhibitory and antioxidant activities.A 80%aqueous methanol was the suitable solvent for extraction of enzyme inhibitors and antioxidants.Among solvent fractions,ethyl acetate fraction had the highest inhibitory activities againstα-glucosidase with a mixed type of inhibition and the strongest antioxidant activities,and was stable under acidic and thermal conditions.The ethyl acetate fraction treated diabetic mice significantly reduced blood glucose level compared with the diabetic control group(13.16 mmol/L vs.22.75 mmol/L after 3 hours of treatment).Oral administration of ethyl acetate fraction did not exhibit toxicity at a dose of 100 mg/kg body weight as determined by body weight changes and liver biochemical parameters.Conclusions:Laurencia dendroidea could be a potential source for production of antidiabetic and antioxidative agents.

Assessment of antidiabetic activity and acute toxicity of leaf extracts from Physalis peruviana L.in guinea-pig

Objective:To verify the antidiabetic activity of leaf extracts from Physalis peruviana L.popularly used in the Eastern part of the Democratic Republic of the Congo and to point out the possible toxicity.Method:Aqueous decoctions prepared from dried leaves powder were administrated to guinea pigs at the dose range of 100 mg/kg to 3.2 g/kg of body weight.The hypoglycemic activity was evaluated by glucose tolerance test,loading animals with glucose 4 g/kg and measuring blood glucose concentrations at various times.The effect was compared to the control and glibenclamide as antidiabetic reference drug.Acute toxicity was evaluated by recording mortality rate,changes on blood biomarkers and damage caused to vital organs.Results:At a dose of 100 mg/kg,the aqueous extract induced a significant reduction of peak concentration at 30 min after glucose loading as compared with control or reference(P<0.05).At doses greater than 400 mg,some alterations on blood,kidney and liver markers were observed.Upper 800 mg/kg,mortality was observed with LD_(50)estimated at about 1280 mg/kg.At the autopsy,vital organs were in haemorrhage and swelling state.Conclusion:The crude aqueous extracts from the leaves of Physalis peruviana L.present hypoglycemic aclivily in animal model,but at high doses the plant may cause severe intoxication.

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%, P<0.05). 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.

Antidiabetic and antidiarrhoeal effects on ethanolic extract of Psidium guajava(L.) Bat.leaves in Wister rats

Objective:To evaluate the antidiabetic and the antidiarrhoeal effects of ethanolic extracts of Psidium guajava leave(EEPGL) in Wisier rais to support its traditional uses.Methods:Oral glucose tolerance test model and alloxan induced diabetic test model were performed to evaluate antidiabetic activity of EEPGL at doses of 1.00.0.50 and 0.75 g/kg respectively.For antidiarrhoeal effects of EEPGL.castor oil-induced diarrhoea model and gastrointestinal motility test with barium sulphate milk model were also assessed at doses of750.500 and 250 mg/kg.respectively.Results:Administration of EEPGL at doses 1.00 and 0.50 g/kg significantly(P<0.05)decreased blood glucose levels in oral glucose tolerance test model as well as 0.75 g/kg dose in alloxan induced diabetic test model in Wister rats(P<0.001).Application of EEPGL at doses of 750 and 500 mg/kg showed antidiarrhoeal effect in castor oil-induced diarrhoeal model(P<0.00 l and P<0.01,respectively),and 750 mg/kg(P<0.01),500 and 250 mg/kg(P<0.05)doses in barium sulphate milk model in aforesaid animals.Conclusions:These results exhibited the significant antidiabetic and antidiarrhoeal activities of ethanolic extracts of Psidium guajava leave in Wister rats.