Modulatory effect of polyphenolic extracts of Ichnocarpus frutescens on oxidative stress in rats with experimentally induced diabetes.

BACKGROUND & OBJECTIVES: The role of oxidative stress in the development of diabetes mellitus and its vascular complications are extensively studied. Hyperglycaemia causes oxidative damage by generation of reactive oxygen species and results in the development of complications. The present study was undertaken with the objective of exploring the anti-hyperglycaemic potential of polyphenolic enriched extract of Ichnocarpus frutescens in streptozotocin induced (n-STZ) neonatal diabetic rats (pups) for six weeks and to study oxidative stress and antioxidant status. METHODS: Two days old pups were rendered diabetic by single injection of streptozotocin (90 mg/kg body wt, ip). At the end of the treatment period, the level of blood glucose, serum biochemical markers, serum lipid levels and liver malondialdehyde, tissue antioxidant levels were measured. RESULTS: A marked rise was observed in the levels of fasting blood glucose (230.33 mg/dl), lipid profiles, lipid peroxidative products and a significant decrease in tissue antioxidants (superoxide dismuatase, catalase and reduced glutathione) and serum high density lipoprotein cholesterol levels in STZ treated rats. Oral administration of polyphenolic extract (150 and 300 mg/kg body wt, po) decreased fasting blood glucose levels (187.66 and 170.50 mg/dl, respectively) of STZ-treated diabetic rats significantly (P<0.01), when compared with control rats. In addition, the polyphenolic extract showed favourable effect (P<0.01) on the reduced tissues antioxidants level, liver glycogen level, high density lipoprotein level, with significant (P<0.01) reduction of elevated lipid peroxidation products. Histopathological study of the pancreas showed the protective role of polyphenolic extract. INTERPRETATION & CONCLUSIONS: Our study showed the antioxidant of effect polyphenolic extract of I. frutescens in STZ induced experimental diabetes. The results also suggested that this polyphenolic rich extract could be potentially useful for hyperglycaemia treatment to correct the diabetic state.

Antioxidant activity of polyphenolic extracts of Ichnocarpus frutescens.

In the present study antioxidant activities by (1,1-diphenyl-2-picrylhydrazyl radical (DPPH), hydrogen peroxide, hydroxyl radical inhibition, hemolysis by hydrogen peroxide assay, reducing power and total antioxidant activities of polyphenolic extract of Ichnocarpus frutescens leaves were investigated. The flavonoids and total polyphenolic contents of the extract were also determined using standard methods. Phytochemical analyses revealed the presence of flavonoids, polyphenols, anthocyanins and simple phenolic acids. The results of antioxidant activities of polyphenol extract obtained by different in vitro methods were varied depending on the method used. Nevertheless, polyphenol extract showed significant inhibitory activities in all in vitro reactive oxygen species scavenging, might be attributed due to the high level of polyphenolic compound. Also, these various antioxidant activities were compared to α-tocopherol and l-ascorbic acid as reference antioxidant compounds. These findings provide evidence that the polyphenolic extract of I. frutescens is a natural source of antioxidant against oxidative damage.

In vitro anticholinergic and antihistaminic activities of Acorus calamus Linn. leaves extracts.

The present investigation was aimed at determining the effects of hexane, acetone, methanol and aqueous extracts of Acorus calamus leaves (ACHE, ACAE, ACME and ACAQE) on cholinergic and histaminic system using isolated frog rectus abdominis muscle and guinea pig ileum. A dose dependent potentiation of Ach response (anticholinesterase like effect) was found with ACAE and ACME at 0.25, 0.5, 0.75 and 1 mg/ml, but at higher dose of ACAE, ACME, ACAQE and ACHE (5, 20 mg/ml) inhibit the Ach response (antinicotinic effect). These results revealed biphasic effect of Acorus calamus leaves extracts on acetylcholine induced contractile response in isolated frog rectus abdominis muscle preparation (i.e. potentiation effect at lower dose and inhibitory effect at higher dose). Studies on isolated guinea pig ileum demonstrated antihistaminic effect in a dose dependent manner (100-1000 µg/ml) with ACAE, ACME and ACAQE. In addition, the dose dependent inhibition of Ach response (antimuscarinic effect) was observed with ACAE and ACME. In conclusion, Acorus calamus leaves extracts exerts antinicotinic, anticholinesterase like activities in isolated frog rectus abdominis muscle and antihistaminic, antimuscarinic effect in guinea pig ileum. It has been suggested that these observed activities can be further studied for therapeutic potential of Acorus calamus leaves in the treatment of cognitive disorders and asthma.

Effect of Biophytum sensitivum on streptozotocin and nicotinamide-induced diabetic rats.

OBJECTIVE: To investigate the effect of aqueous solution of Biophytum sensitivum leaf extract (BSEt) on normal and streptozotocin (STZ)-nicotinamide-induced diabetic rats. METHODS: Diabetes was induced in adult male Wistar rats by the administration of STZ-nicotinamide (40, 110 mg/kg b.w., respectively) intraperitoneally. BSEt (200 mg/kg) was administered to diabetic rats for 28 days. The effect of extract on blood glucose, plasma insulin, total haemoglobin, glycosylated haemoglobin, liver glycogen and carbohydrate metabolism regulating enzymes of liver was studied in diabetic rats. RESULTS: BSEt significantly reduced the blood glucose and glycosylated haemoglobin levels and significantly increased the total haemoglobin, plasma insulin and liver glycogen levels in diabetic rats. It also increased the hexokinase activity and decreased glucose-6-phosphatase, fructose-1, 6-bisphosphatase activities in diabetic rats. CONCLUSIONS: The results of our study suggest that BSEt possesses a promising effect on STZ-nicotinamide-induced diabetes.

Polyphenolic extract of Ichnocarpus frutescens attenuates diabetic complications in streptozotocin-treated diabetic rats.

Diabetic nephropathy is one of the major complications of diabetes. Oxidative stress is implicated as an important mechanism by which diabetes causes nephropathy. The aim of the study was to examine the involvement of oxidative stress in the progression of nephropathy in STZ diabetic animals and to evaluate the potential of polyphenolic extract (PPE) in the treatment of diabetes mellitus. In this study, we examined whether prolonged oral administration of polyphenolic extract of Ichnocarpus frutescens could prevent the progress or improve the outcome of diabetic nephropathy induced by oxidative stress in STZ diabetic rats. Intraperitoneal glucose tolerance test (IPGTT) revealed a significant decrease in blood glucose levels at 180 min after glucose loading in Wistar albino rats fed with PPE. During the eight weeks of experimental period, diabetic rats exhibited wide range of symptoms, including loss of body weight, hyperglycemia, polyuria, proteinuria, renal enlargement, and total renal dysfunction. A significant increase in TBARS level was observed in diabetic kidney, which was accompanied by a significant decrease in enzymatic and non-enzymatic antioxidant levels. After eight weeks, PPE-treated groups showed a lower level of blood glucose compared with non-treated STZ diabetic rats. The increases in urinary albumin and protein after eight weeks of treatment were significantly inhibited by prolonged treatment with PPE. In addition, PPE attenuates the adverse effects on hepatic biomarkers. We found that PPE can effectively protect against aldose reductase activity and protein damage (albumin glycation), and showed that its action was mainly due to enriched polyphenolic content. Our results also showed that treatment with PPE normalized the increase in hyperalgesia (i.e., the response to thermal stimuli) associated with the induction of diabetes by STZ. PPE administration in diabetic rats clearly ameliorated diabetic complications, suggesting not only a natural antioxidant but also supportive therapy for the treatment of type II diabetes.

Antitumor activity of polyphenolic extract of Ichnocarpus frutescens.

AIM: Phytochemical and dietary antioxidants are known to decrease the risk of many diseases such as cancer and cardiovascular diseases. In this study polyphenolic extract (PPE) of leaves of Ichnocarpus frutescens was evaluated for antitumor activity in vivo. MATERIALS AND METHODS: Murine Ehrlich ascites carcinoma (EAC) model was used to assess PPE antitumor activity in vivo. PPE cytotoxicity was determined in vitro in U-937 monocytoid leukemia and K-562 erythroleukemia cell lines. PPE also have been assessed for the free radical scavenging activity against superoxide and nitric oxide radicals. Acute oral toxicity was performed by acute toxic classic method. The total phenolics content was quantified by the Folin-Ciocalteu method. RESULTS: Results of in vivo study showed a significant decrease in tumor volume, viable tumor cell count and a significant increase of life span in the PPE treated group compared to untreated one: the life span of PPE treated animals increased by 53.41% (50 mg PPE/kg) and 73.95% (100 mg PPE/kg). PPE (5, 10 and 20 microg/mL) effectively inhibits in vitro proliferation of U-937 and K-562 cell lines. PPE exhibited pronounced radical scavenging activity with an inhibitory concentration (IC(50)) value of 167.46 microg/mL and 158.52 microg/mL against superoxide and nitric oxide radicals, respectively. CONCLUSION: PPE of Ichnocarpus frutescens possesses strong free radical scavenging activity and anti-tumor activity in vitro and in vivo.

BRONCHODILATOR EFFECT OF ALCOHOLIC EXTRACT OF Euphorbia hirta linn.

The bronchodilator effect of alcoholic extract of Euphorbia hirta Linn was evaluated at different doses (50,100 and 200mg/kg,p.o), using histamine aerosol test model. A dose dependent bronchodilator effect was observed in E. hirta pretreated animals. The extract of E. hirta at a dose of 200mg/kg was found to be more effective in histamine induced broncho constriction and a significant (p<0.001) effect was observed.