Computational Optimization of Bioanalytical Parameters for the Evaluation of the Toxicity of the Phytomarker 1,4 Napthoquinone and its Metabolite 1,2,4-trihydroxynapththalene.

OBJECTIVES: Lawsone (1,4 naphthoquinone) is a non redox cycling compound that can be catalyzed by DT diaphorase (DTD) into 1,2,4-trihydroxynaphthalene (THN), which can generate reactive oxygen species by auto oxidation. The purpose of this study was to evaluate the toxicity of the phytomarker 1,4 naphthoquinone and its metabolite THN by using the molecular docking program AutoDock 4. METHODS: The 3D structure of ligands such as hydrogen peroxide (H2O2), nitric oxide synthase (NOS), catalase (CAT), glutathione (GSH), glutathione reductase (GR), glucose 6-phosphate dehydrogenase (G6PDH) and nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) were drawn using hyperchem drawing tools and minimizing the energy of all pdb files with the help of hyperchem by MM(+) followed by a semi-empirical (PM3) method. The docking process was studied with ligand molecules to identify suitable dockings at protein binding sites through annealing and genetic simulation algorithms. The program auto dock tools (ADT) was released as an extension suite to the python molecular viewer used to prepare proteins and ligands. Grids centered on active sites were obtained with spacings of 54 × 55 × 56, and a grid spacing of 0.503 was calculated. Comparisons of Global and Local Search Methods in Drug Docking were adopted to determine parameters; a maximum number of 250,000 energy evaluations, a maximum number of generations of 27,000, and mutation and crossover rates of 0.02 and 0.8 were used. The number of docking runs was set to 10. RESULTS: Lawsone and THN can be considered to efficiently bind with NOS, CAT, GSH, GR, G6PDH and NADPH, which has been confirmed through hydrogen bond affinity with the respective amino acids. CONCLUSION: Naphthoquinone derivatives of lawsone, which can be metabolized into THN by a catalyst DTD, were examined. Lawsone and THN were found to be identically potent molecules for their affinities for selected proteins.

Serum Biochemical, Histopathology and SEM Analyses of the Effects of the Indian Traditional Herb Wattakaka Volubilis Leaf Extract on Wistar Male Rats.

OBJECTIVES: The present study investigated the protective effect of Wattakaka (W.) volubilis leaf extract against streptozotocin (STZ)-induced diabetes in rats. METHODS: Male Wistar rats were divided into five groups (with six rats in each group) and were fed ad libitum. The rats were fasted for sixteen hours before diabetes was induced by injecting a single dose of 90 mg/kg body weight of STZ in 0.9-percent normal saline through an intraperitoneal route. The five groups were as follows: Group 1: normal control (saline-treated), Group 2: untreated diabetic rats, Groups 3 and 4: diabetic rats treated orally with petroleum ether cold maceration extract (PEME) of W. volubilis(50 and 100 mg/kg body weight), and Group 5: diabetic rats treated orally with metformin (250 mg/kg body weight). All rats received treatment for 21 days. For the STZ-induced diabetic rats, the blood-glucose, α-amylase, total protein and alanine transaminase (ALT) levels were measured on days 7,14 and 21 of the treatment with PEME of W. volubilis and the treatment with metformin. Histopathological changes in the liver were examined with hematoxylin-eosin staining. Morphological changes in the liver were also examined with glutaraldehyde fixation. RESULTS: The treatments with PEME of W. volubilis and with metformin in experimental rats by oral injections for 21 days produced reductions in the levels of serum biochemical markers. Histopathology and scanning electron microscopy results showed that the administrations of PEME of W. volubilis and of metformin suppressed the generation of abnormal liver cells in the STZ-treated rats. CONCLUSION: These results suggest that both PEME of W. volubilis and metformin have a protective effect against STZ-induced diabetes.

Biological Parameters for Evaluating the Toxic Potency of Petroleum Ether Extract of Wattakaka volubilis in Wistar Female Rats.

OBJECTIVES: The present study investigated the toxic properties of petroleum ether extract of Wattakaka (W.) volubilis in Wistar female rats. METHODS: An in vitro brine shrimp lethality bioassay was studied in A. Salina nauplii, and the lethality concentrations were assessed for petroleum ether extract of W. volubilis. A water soluble portion of the test extract was used in different concentrations from 100-1000 µg/mL of 1 mg/mL stock solution. A 24-hours incubation with a 1-mL aliquot in 50 mL of aerated sea water was considered to calculate the percentage rate of dead nauplii with test extract administration against a potassium-dichromate positive control. The acute and the sub-acute toxicities of petroleum ether extract of W. volubilis were evaluated orally by using gavage in female Wistar rats. Food and water intake, body weight, general behavioral changes and mortality of animals were noted. Toxicity or death was evaluated following the administration of petroleum ether extract for 28 consecutive days in the female rats. Serum biochemical parameters, such as alanine aminotransferase (ALT), alkaline phosphatase (ALP), bilirubin, total cholesterol, triglyceride, total protein, glucose, urea, creatinine, sodium, potassium and α-amylase levels, were measured in the toxicity evaluations. Pathological changes in isolated organs, such as the liver, kidneys, and pancreas, were also examined using hematoxylin and eosin dye fixation after the end of the test extract's administration. RESULTS: The results of the brine-shrimp assay indicate that the evaluated concentrations of petroleum ether extract of W. volubilis were found to be non-toxic. In the acute and the sub-acute toxicity evaluations, no significant differences were observed between the control animals and the animals treated with extract of W. volubilis. No abnormal histological changes were observed in any of the animal groups treated with petroleum ether extract of W. volubilis. CONCLUSION: These results suggest that petroleum ether extract of W. volubilis has a non-toxic effect in Wistar female rats.

An inside to the better understanding of the ethnobotanical route to drug discovery--the need of the hour.

For pharmaceuticals ranging from Digitalis to vincristine, the ethnobotanical approach to drug discovery has proven successful. The value of ethnobotanical information in drug development is based on several factors, which are discussed. Published ethnomedical information has many strengths and weaknesses relative to the ability to establish a corresponding biological effect in the laboratory. The ability to correlate ethnomedical reports with corresponding scientific studies could lead to improved selection of plants for further scientific studies. The application of NAPRALERT database in this regard is also discussed. An elaborate plant to drug pathway has been traced out for young researchers to make the drug discovery pathway more approachable. Various cautions related to possible errors during the ethnobotanical approach have also been highlighted.