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Objective: To explore antioxidant potential, anti-cancer activity, and phytochemicals of Commelina benghalensis L. Methods: The roots of Commelina benghalensis were extracted in different solvents (methanol, ethanol, benzene, chloroform, n-hexane) with a range of polarity. Antioxidant activity was evaluated by reducing power assay, DPPH radical scavenging activity and phosphomolybdenum method, cytotoxicity by MTT assay, apoptotic and cell cycle analysis by flow cytometry, migratory and invasive potential by wound scratch assay and invasion assay, respectively, functional groups analysis by FT-IR spectroscopy and phytochemicals by aluminum chloride colorimetric and Folin-Ciocalteu methods. Results: The extracts showed worthy antioxidant potential. The chloroform extract demonstrated the most significant cytotoxic effect on MDA-MB-231 (breast cancer) cell line, induced apoptosis and reduced migratory and invasive potential of MDA-MB-231 cells. Methanol and ethanol extracts presented good yield of total phenolic and total flavonoid contents. The FTIR spectroscopic studies revealed different characteristic peak values with various functional compounds such as alkenes, alkanes, aliphatic amines, aromatics, alkyl halides, carboxylic acid, alcohols, ester, aldehydes and ketones. Conclusions: The results demonstrate the potential use of Commelina benghalensis as a good antioxidant with significant anti-cancer effect.

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Objective: To investigate the inhibitory effects against dengue virus serotype 2 (DENV-2) by five different fractions (extracted by methanol, ethanol, benzene, chloroform and n-hexane) of Rumex dentatus, Commelina benghalensis, Ajuga bracteosa and Ziziphus mauritiana, as well as their constituents (gallic acid, emodin, and isovanillic acid). Methods: All the samples were tested for cytotoxicity on baby hamster kidney cells by MTT assay and for anti-DENV-2 activity by plaque reduction neutralization assay using two DENV-2 doses (45 and 90 plaque- forming units or PFU). Results: All the samples except isovanillic acid exhibited significant prophylactic effects against DENV-2 infectivity (without cytotoxicity) when administered to cells before infection, but were not effective when given 6 h post-infection. The methanol extract of Rumex dentatus demonstrated the highest antiviral efficacy by inhibiting DENV-2 replication, with IC

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The chloroform and hexane fractions and their sub-fractions of Polygonum bistorta (Polygonaceae) were evaluated for their cytotoxic activity against P338 (Murine lymphocytic leukaemia), HepG2 (Hepatocellular carcinoma), J82 (Bladder transitional carcinoma), HL60 (Human leukaemia), MCF7 (Human breast cancer) and LL2 (Lewis lung carcinoma) cancer cell lines in culture. Both the chloroform and hexane fractions and a few of their sub-fractions showed moderate to very good activity against P388, HL60 and LL2 cancer cell lines. Both active and non-active fractions were further investigated for their chemical constituents. A total of nine compounds, viz. 24(E)-ethylidenecycloartanone (1), 24(E)-ethylidenecycloartan-3alpha-ol (2), cycloartane-3,24-dione (3), 24-methylenecycloartanone (4), friedelin (5), 3beta-friedelinol (6), beta-sitosterol (7), gamma-sitosterol (8) and beta-sitosterone (9) were isolated. One of the pure compounds, 24(E)-ethylidenecycloartanone 1, which was obtained in sufficient quantity, was tested for its cytotoxicity against P388, LL2, HL60 and WEHI164 (Murine fibrosarcoma) cancer cell lines but was found to have no activity even at a concentration of 100 microg/mL.

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Developing atherosclerotic lesions in hypercholesterolemic rabbits are depleted in zinc, while iron accumulates. This study examined the influence of zinc supplementation on the development of atherosclerosis and used isotope dilution gas chromatography-mass spectrometry techniques to measure biomarkers of oxidative lipid damage in atherosclerotic rabbit aorta. Our previous method for F(2)-isoprostane measurement was adapted to include the quantitation of cholesterol oxidation products in the same sample. Two groups of New Zealand white rabbits were fed a high cholesterol (1% w/w) diet and one group was also supplemented with zinc (1 g/kg) for 8 weeks. Controls were fed a normal diet. Zinc supplementation did not significantly alter the increase in total plasma cholesterol levels observed in animals fed high cholesterol. However, in cholesterol-fed animals zinc supplementation significantly reduced the accumulation of total cholesterol levels in aorta which was accompanied by a significant reduction in average aortic lesion cross-sectional areas of the animals. Elevated levels of cholesterol oxidation products (5,6-alpha and beta cholesterol epoxides, 7beta-hydroxycholesterol, 7-ketocholesterol) in aorta and total F(2)-isoprostanes in plasma and aorta of rabbits fed a cholesterol diet were significantly decreased by zinc supplementation. Our data indicate that zinc has an antiatherogenic effect, possibly due to a reduction in iron-catalyzed free radical reactions.

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A new pentacyclic triterpenoid, 2alpha,3beta-dihydroxylup-12-en-28-oic acid (1) and a rarely encountered pentacyclic triterpenoid, 3beta-hydroxylup-12-en-28-oic acid (2), together with five known compounds, friedelin (3), 3beta-friedelinol (4), betulinic acid (5), oleanolic acid (6) and beta-sitosterol (7) were isolated from the chloroform extract of stem bark of Eugenia grandis (Syn: Syzygium grande). The structure and stereochemistry of the new compound (1) and the rarely encountered compound (2) were established by 1D and 2D NMR spectroscopic techniques. All the above isolated compounds from this plant are reported for the first time.

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Two new compounds, 24(E)-ethylidenecycloartanone (1) and 24(E)-ethylidenecycloartan-3alpha-ol (2) were isolated from the rhizomes of Polygonum bistorta, together with seven known compounds viz., cycloartane-3,24-dione (3), 24-methylenecycloartanone (4), gamma-sitosterol (5), beta-sitosterol (6), beta-sitosterone (7), friedelin (8) and 3beta-friedelinol (9). All the cycloartane type triterpenoids, compounds 7 and 8 are reported for the first time from this plant. A combination of 1D and 2D NMR spectroscopy and MS were mainly used to elucidate the structures of the new compounds 1 and 2.

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This investigation is aimed to determine whether the biosynthesis of H(2)S, an endogenous vasodilator gas, is altered in the streptozotocin-diabetic rat. Plasma H(2)S concentration as well as the activity, and expression, of H(2)S synthesizing enzymes (namely cystathionine-gamma-lyase (CSE) and cystathionine-beta-synthetase (CBS)) were measured in various tissues of non-diabetic, streptozotocin-diabetic and insulin-treated diabetic rats. H(2)S formation in pancreas and liver was increased in diabetic rats. Both CSE and CBS mRNAs were increased in liver of diabetic animals. Similarly, CBS mRNA was increased in pancreas. Insulin treatment restored the changes in H(2)S metabolism seen. The findings of this study suggest that the metabolism of H(2)S in pancreas and liver is altered in the streptozotocin-diabetic rat. This is the first study in which a derangement in H(2)S biosynthesis in diabetes has been demonstrated. H(2)S may play a part in the aetiology or development of diabetes in this animal model.

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alpha-Hederin, a pentacyclic triterpene saponin isolated from the seeds of Nigella sativa, was recently reported to have potent in vivo antitumor activity against LL/2 (Lewis Lung carcinoma) in BDF1 mice. In this study we observed that alpha-hederin caused a dose- and time-dependent increase in apoptosis of murine leukemia P388 cells. In order to evaluate the possible mechanisms for apoptosis, the effects of alpha-hederin on intracellular thiol concentration, including reduced glutathione (GSH), and protein thiols, and the effects of pretreatment with N-acetlycysteine (NAC), a precursor of intracellular GSH synthesis, or buthionine sulfoxime (BSO), a specific inhibitor of intracellular GSH synthesis, on alpha-hederin-induced apoptosis were investigated. It was found that alpha-hederin rapidly depleted intracellular GSH and protein thiols prior to the occurrence of apoptosis. NAC significantly alleviated alpha-hederin-induced apoptosis, while BSO augmented alpha-hederin-induced apoptosis significantly. The depletion of cellular thiols observed after alpha-hederin treatment caused disruption of mitochondrial membrane potential (deltapsi(m)) and subsequently increased the production of reactive oxygen species (ROS) in P388 cells at an early time point. Bongkrekic acid (BA), a ligand of the mitochondrial adenine nucleotide translocator, and cyclosporin (CsA) attenuated the alpha-hederin-induced loss of deltapsi(m), and ROS production. Thus, oxidative stress after alpha-hederin treatment is an important event in alpha-hederin-induced apoptosis. As observed in this study, permeability transition of mitochondrial membrane occurs after depletion of GSH and precedes a state of reactive oxygen species (ROS) generation. Further, we observed that alpha-hederin caused the release of cytochrome c from the mitochondria to cytosol, leading to caspase-3 activation. Our findings thus demonstrate that changes in intracellular thiols and redox status leading to perturbance of mitochondrial functions are important components in the mechanism of alpha-hederin-induced cell death.

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Several studies have indicated a relationship between body iron content and cardiovascular disease, although other studies have not. There are also suggestions that zinc has an antioxidant and antiatherosclerotic effect. We have used Nuclear Microscopy, using the combination of Scanning Transmission Ion Microscopy (STIM), Rutherford Backscattering Spectrometry (RBS), and Proton Induced X-ray Emission (PIXE) to map and quantify iron and zinc levels in newly formed atherosclerotic lesions. Sixteen New Zealand White rabbits fed on a high cholesterol diet were divided into four groups of 4 rabbits each. Six weeks into the high cholesterol diet, two groups were treated with the iron chelating agent desferrioxamine, for 2 weeks and 4 weeks, respectively, by surgically implanting with Alzet osmotic pumps (Alza Corporation, Palo Alto, CA, USA) containing desferal (0.5 g/ml). The other two groups served as controls, and were surgically implanted with osmotic pumps containing saline. Tissue sections were taken from the aortic arch, flash frozen, and air-dried. Analysis of atherosclerotic lesions indicated a trend (p =.07) to a reduction in the progression of the lesion after 4 weeks of desferrioxamine treatment. For each of the control and desferrioxamine-treated animals however, the more extensive lesions contained a higher concentration of iron and a lower concentration of zinc. Our results are consistent with the view that early lesion formation may be accelerated by free radical production caused by increased iron levels, that zinc might antagonize such effects, and that more prolonged desferal treatment might have an antiatherosclerotic effect.

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