Electrochemical Response of Saccharomyces cerevisiae Corresponds to Cell Viability upon Exposure to Dioclea reflexa Seed Extracts and Antifungal Drugs.

Dioclea reflexa bioactive compounds have been shown to contain antioxidant properties. The extracts from the same plant are used in traditional medical practices to treat various diseases with impressive outcomes. In this study, ionic mobility in Saccharomyces cerevisiae cells in the presence of D. reflexa seed extracts was monitored using electrochemical detection methods to link cell death to ionic imbalance. Cells treated with ethanol, methanol, and water extracts were studied using cyclic voltammetry and cell counting to correlate electrochemical behavior and cell viability, respectively. The results were compared with cells treated with pore-forming Amphotericin b (Amp b), as well as Fluconazole (Flu) and the antimicrobial drug Rifampicin (Rif). The D. reflexa seed water extract (SWE) revealed higher anodic peak current with 58% cell death. Seed methanol extract (SME) and seed ethanol extract (SEE) recorded 31% and 22% cell death, respectively. Among the three control drugs, Flu revealed the highest cell death of about 64%, whereas Amp b and Rif exhibited cell deaths of 35% and 16%, respectively, after 8 h of cell growth. It was observed that similar to SWE, there was an increase in the anodic peak current in the presence of different concentrations of Amp b, which also correlated with enhanced cell death. It was concluded from this observation that Amp b and SWE might follow similar mechanisms to inhibit cell growth. Thus, the individual bioactive compounds from the water extracts of D. reflexa seeds could further be purified and tested to validate their potential therapeutic application. The strategy to link electrochemical behavior to biochemical responses could be a simple, fast, and robust screening technique for new drug targets and to understand the mechanism of action of such drugs against disease models.

Dioclins A and B, new antioxidant flavonoids from Dioclea reflexa.

Dioclins A (1) and B (2), the new flavonoids, have been isolated from the ethyl acetate soluble fraction of the roots of Dioclea reflexa along with 3,5-dihydroxy-4 methoxybenzoic acid (3), lupeol (4) and the rare dipeptide, auratiamide acetate (5). Their structures have been elucidated by spectroscopic techniques. The compounds 1 and 2 showed a significant antioxidant activity in DPPH radical scavenging assay.

Purification, partial characterization and immobilization of a mannose-specific lectin from seeds of Dioclea lasiophylla mart.

Lectin from the seeds of Dioclea lasiophylla (DlyL) was purified in a single step by affinity chromatography on a Sephadex® G-50 column. DlyL strongly agglutinated rabbit erythrocytes and was inhibited by monosaccharides (D-mannose and α-methyl-D-mannoside) and glycoproteins (ovalbumin and fetuin). Similar to other Diocleinae lectins, DlyL has three chains, α, ß and γ, with mass of 25,569 ± 2, 12,998 ± 1 and 12,588 ± 1 Da, respectively, and has no disulfide bonds. The hemagglutinating activity of DlyL was optimal in pH 8.0, stable at a temperature of 70 °C and decreased in EDTA solution, indicating that lectin activity is dependent on divalent metals. DlyL exhibited low toxicity on Artemia sp. nauplii, but this effect was dependent on the concentration of lectin in solution. DlyL immobilized on cyanogen bromide-activated Sepharose® 4B bound 0.917 mg of ovalbumin per cycle, showing the ability to become a tool for glycoproteomics studies.

Central nervous system effects of Dioclea grandiflora pods on mice / Efectos en el sistema nervioso central de la vaina de Dioclea grandiflora en camundongos

Many plant substances are known for their interference with the central nervous system (CNS). Dioclea grandiflora Mart. Ex. Benth (Fabaceae) is a plant used in folk medicine to treat prostate disorders and kidney stones whose extracts from its seeds and root barks were reported to have a significant activity on the CNS and analgesic effect in rodents. In this study, the psychopharmacological activities of D. grandiflora were investigated, using the pods of this plant. Swiss mice were submitted to acute treatments with ethanol extract from the pods of D. grandiflora (EDgP) at doses of 75, 150 and 300 mg/kg by intraperitoneal administration followed by the evaluation of anxiety, depressant and anticonvulsant-related responses. The treatment with EDgP produced a depressant activity on the CNS and a sedative effect in mice. These findings suggest that EDgP has a central activity in mice, indicating an anxiogenic effect.

Varias sustancias de plantas son conocidas por su acción en el sistema nervioso central (SNC). La Dioclea grandiflora Mart. Ex. Benth (Fabaceae) es una planta utilizada en la medicina popular para tratar enfermedades en la próstata y piedras en los riñones, cuyos extractos de sus semillas y de las cáscaras de sus raíces presentan una actividad significativa sobre el SNC y efecto analgésico en roedores. En este estudio, las actividades psicofarmacológicas de D. grandiflora fueron investigadas, utilizando la vaina de la planta. Camudongos Swiss fueron sometidos a tratamientos agudos por la administración intraperitoneal del extracto etanólico de la vaina de D. grandiflora (EDgP) en dosis de 75, 150 y 300 mg/kg administrados intraperitonealmente seguida por la evaluación de respuestas relacionadas con la ansiedad, depresión y anticonvulsivo. El tratamiento con EDgP produjo una actividad depresora sobre el sistema nervioso central y un efecto sedante en camundongos. Estos resultados sugieren que EDgP tiene una actividad central en camundongos, indicando un efecto ansiogénico.

Pharmaceutical properties and toxicology of Dioclea grandiflora.

CONTEXT: Since the beginning of civilization, herbal medicines have been an important source for human beings to treat their ailments. Despite the large number of synthetic remedies available in the market, the use of plants is seen as a great challenge in the search for new substances endowed with therapeutic properties. One example is Dioclea grandiflora Mart. ex Benth. (Leguminosae) employed in traditional medicine to treat prostate disorders and kidney stones. OBJECTIVES: This work presents a brief overview of D. grandiflora, including a description of the plant, its chemical composition and pharmacological properties. METHODS: This review gathers information available in the scientific literature compiled from databases such as Science Direct, PubMed, Dr. Dukes Phytochemical and Ethnobotany, Missouri Botanical Garden and The International Plant Names Index. RESULTS: The information found in the literature showed that flavonoids are the major constituents of D. grandiflora that account for most of the pharmacological properties so far disclosed. Several studies have revealed that D. grandiflora possesses antinociceptive, cardiovascular, antioxidant and anti-inflammatory activities. CONCLUSION: Research shows that D. grandiflora is a potential source of compounds pertaining medicinal applications. It provides an interesting subject in the search for new drugs of natural origin.

Purification and partial characterization of a novel lectin from Dioclea lasiocarpa Mart seeds with vasodilator effects.

A lectin from seeds of Dioclea lasiocarpa (DLL) was purified in a single step by affinity chromatography in a Sephadex G-50 column. DLL haemagglutinated rabbit erythrocytes showing stability even after 1 h of exposure to a different pH values (optimal between pH 6.0 and 8.0) but was inhibited after incubation with D-mannose and D-glucose. The pure protein possessed a molecular weight of 25 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis and 25,410Da by mass spectrometry. The results analyzed by the software SELCON 3 indicate that ß-sheet secondary structures are predominant in DLL (approximately 40.2% antiparallel ß-sheet, 4.6% parallel ß-sheet, 7.2% α-helices, 17.3% turns, and 28.7% unordered structures). Mechanical activity of isolated aorta from rat measured by cumulative concentration curves of DLL, performed at the contraction plateau induced by phenylephrine in either endothelium-intact or denuded aorta. DLL (IC(50) = 34.12 ± 3.46 µg/ml) relaxed precontracted endothelized aortic rings by 34.61 ± 9.06%, 55.19 ± 11.9%, and 81.33 ± 14.35%, respectively, at 10 µg/ml (initial concentration), 30 µg/ml, and 100 µg/ml (maximum effect). All effects occurred via interaction with lectin domains and participation of nitric oxide.

Antinociceptive activity of the chloroform fraction of Dioclea virgata (Rich.) Amshoff (Fabaceae) in mice.

Acute treatment with the chloroform fraction of Dioclea virgata (Rich.) Amshoff (CFDv) in mice produced decreased ambulation and sedation in the behavioral pharmacological screening. Doses of 125 and 250 mg/kg CFDv decreased latency of sleep onset in the test of sleeping time potentiation. In the open field, animals treated with CFDv reduced ambulation and rearing (250 mg/kg), as well as defecation (125; 250 mg/kg). Regarding the antinociceptive activity, CFDv (125, 250, 500 mg/kg) increased latency to first writhing and decreased the number of writhings induced by acetic acid. In the formalin test, CFDv (250 mg/kg) decreased paw licking time in the first and second phases indicating antinociceptive activity that can be mediated both peripherally and at the central level. CFDv did not affect motor coordination until 120 minutes after treatment. CFDv shows psychopharmacological effects suggestive of CNS-depressant drugs with promising antinociceptive activity.

Antinociceptive and toxicological effects of Dioclea grandiflora seed pod in mice.

The acute treatment of mice with an ethanolic extract from the seed pod of Dioclea grandiflora (EDgP) at doses of 75, 150 and 300 mg/kg by intraperitoneal administration produced a significant antinociceptive effect as displayed by the acetic acid-induced writhing test and the formalin test. The antinociception was observed through the first (neurogenic pain) and second (inflammatory pain) phases in the formalin test. The hot plate test did not show an increase in the antinociceptive latency whereas the motor performance was affected by the administration at 300 mg/kg at the beginning (30 minutes) of the observation period but not at later periods (60 and 120 minutes). These results suggest that EDgP has a central antinociceptive action and a possible anti-inflammatory activity in mice.

Pharmacological analysis of the neutrophil migration induced by D. rostrata lectin: involvement of cytokines and nitric oxide.

In the present study, we investigated the involvement of resident cell and inflammatory mediators in the neutrophil migration induced by chemotactic activity of a glucose/mannose-specific lectin isolated from Dioclea rostrata seeds (DrosL). Rats were injected i.p. with DrosL (125-1000 microg/cavity), and at 2-96 h thereafter the leukocyte counts in peritoneal fluid were determined. DrosL-induced a dose-dependent neutrophil migration accumulation, which reached maximal response at 24 h after injection and declines thereafter. The carbohydrate ligand nearly abolished the neutrophil influx. Pre-treatment of peritoneal cavities with thioglycolate which increases peritoneal macrophage numbers, enhanced neutrophil migration induced by DrosL by 303%. However, the reduction of peritoneal mast cell numbers by treatment of the cavities with compound 48/80 did not modify DrosL-induced neutrophil migration. The injection into peritoneal cavities of supernatants from macrophage cultures stimulated with DrosL (125, 250 and 500 microg/ml) induced neutrophil migration. In addition, DrosL treatment induced cytokines (TNF-alpha, IL-1beta and CINC-1) and NO release into the peritoneal cavity of rats. Finally, neutrophil chemotaxis assay in vitro showed that the lectin (15 and 31 microg/ml) induced neutrophil chemotaxis by even 180%. In conclusion, neutrophil migration induced by D. rostrata lectin occurs by way of the release of NO and cytokines such as IL-1beta, TNF-alpha and CINC-1.