Antidiabetic and Antioxidant Potentials of Amaranthus hybridus in Streptozotocin-Induced Diabetic Rats.

CONTEXT: Amaranthus hybridus (Amaranthaceae) has been used as a folk medicine in southern parts of India for the treatment of diabetes. OBJECTIVE: This research evaluates the antidiabetic and antioxidant effects of Amaranthus hybridus ethanol leaf extract (AHELE) in streptozotocin-induced diabetic rats. METHODS: Blood glucose levels of diabetic rats were measured on days 1, 4, 7, and 15 after oral administration of AHELE at doses of 200 and 400 mg/kg for 14 days. The effects of extract were observed on serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, serum alkaline phosphatase, cholesterol, high- and low-density lipoprotein, antioxidant potential, and histopathological changes. RESULT: AHELE (200 and 400 mg/kg) caused a significant (p < 0.001) reduction in blood glucose levels on day 15 (152.2 and 181.2 mg/dL, respectively versus diabetic control 287.0 mg/dL). The extract also improved serum biochemical parameters associated with diabetes. A significant (p < 0.001) decrease in malondialdehyde protein (liver: 15.92, 12.29 nmol/mg, and kidney: 13.92, 10.29 nmol/mg vs. diabetic control 25.49, 24.49 nmol/mg), increase in superoxide dismutase protein (14.01; 17.47 IU/mg, and 25.01; 37.47 IU/mg vs. diabetic control 9.65; 15.65 IU/mg), catalase protein (35.80, 44.49, and 39.80, 49.69 nmol/min/mg vs. diabetic control 18.45, 20.85 nmol/min/mg) and reduced glutathione protein (44.77, 55.08 and 40.77, 51.08 µM/gm vs. diabetic control 29.81, 26.50 µM/gm) were observed. CONCLUSIONS: The study reveals that treatment of diabetic rats with AHELE significantly reduced hyperglycemia-associated oxidative damage. This could provide a rationale for the use of the plant to treat diabetes in folk medicine.

Protective Effect of Ethyl Acetate Fraction of Stereospermum Suaveolens Against Hepatic Oxidative Stress in STZ Diabetic Rats.

Stereospermum suaveolens is a folk remedy for the treatment of diabetes and liver disorders in southern parts of India. In the present study, the protective effect of the ethyl acetate fraction of ethanol extract from S. suaveolens against hepatic oxidative stress was evaluated in streptozotocin (STZ)-induced diabetic rats for 14 days. The ethyl acetate fraction was administered orally to the STZ diabetic rats at the doses of 200 and 400 mg/kg. Blood glucose level was measured according to glucose oxidase method. In order to determine hepatoprotective activity, changes in the levels of serum biomarker enzymes such as aspartate transaminase (AST), alanine transaminase (ALT), and serum alkaline phosphatase (SALP) were assessed in the ethyl acetate fraction treated diabetic rats and were compared with the levels in diabetic control rats. In addition, the antioxidant activity of ethyl acetate fraction was evaluated using various hepatic parameters such as thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT). It was found that administration of ethyl acetate fraction (200 and 400 mg/kg) produced a significant (P < 0.001) fall in fasting blood glucose level, TBARS, bilirubin, AST, ALT, and SALP, while elevating the GSH levels, and SOD and CAT activities in diabetic rats. Histopathologic studies also revealed the protective effect of ethyl acetate fraction on the liver tissues of diabetic rats. It was concluded from this study that the ethyl acetate fraction from ethanol extract of S. suaveolens modulates the activity of enzymatic and nonenzymatic antioxidants and enhances the defense against hepatic oxidative stress in STZ-induced diabetic rats.

Anti-inflammatory activity of Premna corymbosa (Burm.f.) Rottl. & Willd. leaves extracts in Wistar albino rats.

OBJECTIVE: To evaluate the acute toxicity and to investigate the effect of Premna corymbosa ethanolic extract (PCEE) at doses of 200 and 400 mg/kg body weight in acute and chronic models of inflammation in experimental animals. METHODS: In the acute toxicity study, a single dose of PCEE of 2 000 mg/kg body weight, p.o. was administered and observed for 48 h. In acute models as egg albumin induced paw edema and chronic model as cotton pellet methods was followed. RESULTS: In acute models, egg albumin induced paw edema PCEE significantly (P<0.01) inhibited the edema formation. In chronic model, cotton pellet induced granuloma formation in rats PCEE significantly (P<0.01) reduced the granuloma formation with percentage inhibition of 35.17% and 50.38 % respectively. CONCLUSIONS: The present study establishes the antiinflammatory activity of Premna corymbosa leaves.

Effect of ethanolic extract of Premna corymbosa (Burm. f.) Rottl. & Willd. leaves in complete Freund's adjuvant-induced arthritis in Wistar albino rats.

Premna corymbosa (Burm.f.) Rottl. & Willd. (Verbenaceae) is a small tree used in traditional medicine for rheumatic disorders and it is the one of the ingredient in many ayurvedic preparations available in the market for inflammatory disorder uses. The aim of this work was to evaluate the acute toxicity and anti-arthritic activity of P. corymbosa ethanolic extract (PCEE) in experimental animals. In the acute toxicity study, a single dose of PCEE, 2000 mg kg(-1) body weight p.o., was administered. The animals observed for 48 h showed no clinical signs, no mortality, and the extract was found to be safe. To evaluate the anti-arthritic activity of PCEE in Complete Freund's Adjuvant (CFA)-induced arthritis in rats were conducted. The results indicated that the long-term treatment significantly (p < .01) suppressed the development of chronic arthritis induced by CFA. This study established the anti-arthritic activity of P. corymbosa leaves.

Antinociceptive activity of Premna corymbosa (Burm.f.)Rottl. & Willd.

The aim of this work was to evaluate the acute toxicity and antinociceptive activity of an ethanolic extract of Premna corymbosa in animal models. In the acute toxicity study, the ethanolic extract showed no clinical signs and mortality of the animals and was found to be safe. In the acetic acid-induced writhing model, the ethanolic extract at a dose of 200 or 400 mg kg(-1) body weight significantly (p < .01) inhibited the writhing response by 42.57% and 54.67%, respectively. In the hot plate test, the extract produced a significant (p < .01) increase in latency with 34.50% and 51.08% of protection in a dose-related manner. This study has established the analgesic properties of P. corymbosa (Burm.f.) Rottl. and Willd. The beta-sitosterol or luteolin present in the ethanolic extract may contribute the antinociceptive activity of P. corymbosa.

Induction of resistance in host against the infection of leaf blight pathogen (Alternaria palandui) in onion (Allium cepa var aggregatum).

The Pseudomonas fluorescens isolate Pfl was found to inhibit the growth of pathogen Alternaria palandui, in vitro. In the present study, foliar application of a talc-based formulation of Pfl significantly reduced the incidence of leaf blight of onion, caused by A. palandui. Induction of defense-related proteins viz., chitinase, beta-1,3 glucanase, peroxidase (PO) and polyphenol oxidase (PPO) by application of Pfl, was studied against A. palandui infection in resistant (IHR 56) and susceptible (MDUI) onion cultivars. Chitinase in both cultivars, with or without challenge-inoculation of A. palandui revealed changes in the isoform pattern. The Native-PAGE of PO showed induction of PO2 isoform in both the cultivars, in response to inoculation of pathogen. Isoform analysis of PPO also exhibited induction in the Pfl-treated plants challenged with pathogen. Similarly, the activity of beta-1,3-glucanase was greatly induced in Pfl-treated plants, challenged with pathogen as compared to controls. Thus, the P. fluorescens-treated plants showed significant increase in the levels of the defense enzymes, in comparison to the plants challenged with the pathogen.