Novel observations of genotypic and metabolic characteristics of three subspecies of Streptococcus gallolyticus.
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Animals↗
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Differential isolatoion of Pythium species from soil by means of selective media,temperature, and pH.
Pythium aphanidermatum, with an optimum temperature for growth at 35C, grew welland was readily isolated from soil on pimaricin-vancomycin medium (MPVM) when incubated for 24h at 38-40C. The pH of the medium affected recovery; maximum numbers developed above pH 6.0. Other Pythium spp. were recovered on MPVM at 20-25C, but were excluded by incubation at 38-40C. These Pythium spp. included P. ultimun, P. paroecandrum, P. irregular, P. mamillatum, and an unidentified Pythium sp. These species grew well and were readily siolated from soil on gallic acid medium (GAM) when incubated for 24-8h at 20 C.P. aphanidermatum and P. myriotylum grew from mycelium on GAM, but their oospores did not germinate nor could they be isolated from soilon this medium. P. myriotylum grew well on MPVM, but was only rarely isolated, evenfrom soils with known high potential for disease caused by P. myriotylum. Propagules of Pythium were enumerated by a plate-dilution frequency method or by a smearplateethod is valuable for studies on the ecology, survival, and inoculum potential in soils with mixed populations of P. aphanidermatum and other Pythium spp.
Culture Media↗
Hepatoprotective effect of Phyllanthus in Taiwan on acute liver damage induced by carbon tetrachloride.
The effect of oral administration of Phyllanthus methanolic extracts (PME) (i.e. P. acidus, P. emblica, P. myrtifolius, P. multiflorus, P. amarus, P. debilis, P. embergeri, P. hookeri, P. tenellus, P. urinaria L.s. nudicarpus, P. urinaria L.s. urinaria) or gallic acid (GA) on the progression of acute liver damage induced by CCl(4) in rats was examined by morphological and biochemical methods. P. acidus, P. urinaria L.s. urinaria, GA at a dose of 0.5 g/kg, and P. emblica, P. urinaria L.s. nudicarpus at a dose of 1.0 g/kg attenuated CCl(4)-induced increase in serum glutamate-oxalate-transaminase (GOT). P. acidus, P. urinaria L.s. nudicarpus, P. urinaria L.s. urinaria, GA at a dose of 0.5 g/kg, and P. emblica, P. amarus, P. hookeri, P. tenellus at a dose of 1.0 g/kg attenuated CCl(4)-induced increase in serum glutamate-pyruvate-transaminase (GPT). Concurrently, P. acidus, P. multiflorus, P. embergeri, P. hookeri, P. tenellus and P. urinaria L.s. urinaria elevated the activity of liver reduced glutathione peroxidase (GSH-Px). Since the protective effects of P. acidus, P. emblica, P. myrtifolius, P. embergeri, P. urinaria L.s. nudicarpus, P. urinaria L.s. urinaria and GA correlate with a reduction in liver infiltration and focal necrosis observed using histological methods, these data demonstrate that P. acidus and P. urinaria L.s. urinaria are hepatoprotective and antioxidant agents.
Animals↗
Norepinephrine-induced calcium signaling pathways in afferent arterioles of genetically hypertensive rats.
This study provides new information about the relative importance of calcium mobilization and entry in the renal vascular response to adrenoceptor activation in afferent arterioles isolated from 7- to 8-wk-old Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR). Intracellular free calcium concentration ([Ca(2+)](i)) was measured in microdissected arterioles utilizing ratiometric photometry of fura 2 fluorescence. There was no significant strain difference in baseline [Ca(2+)](i). Norepinephrine (NE; 10(-6) and 10(-7) M) elicited immediate, sustained increases in [Ca(2+)](i). The general temporal pattern of response to 10(-6) M NE consisted of an initial peak and a maintained plateau phase. The response to NE was partially blocked by nifedipine (10(-6) M) or 8-(N,N-diethylamino) octyl-3,4,5-trimetoxybenzoate (TMB-8; 10(-5) M). A calcium-free external solution abolished the sustained [Ca(2+)](i) plateau response to NE, with less influence on the peak response. In the absence of calcium entry, TMB-8 (10(-5) M) completely blocked the calcium response to NE in WKY but not SHR, suggesting strain differences in mobilization. A higher concentration of TMB-8 (10(-4) M), however, blocked all discernible mobilization in both strains. We conclude that there are differences in Ca(2+) handling in renal resistance vessels between young WKY and SHR with respect to mobilization stimulated by alpha-adrenoceptors. Afferent arterioles of young SHR appear to have a larger inositol-1,4,5-trisphosphate-sensitive pool or release from a site less accessible to TMB-8.
Adrenergic alpha-Agonists↗
Phase II study of pomegranate juice for men with rising prostate-specific antigen following surgery or radiation for prostate cancer.
PURPOSE: Phytochemicals in plants may have cancer preventive benefits through antioxidation and via gene-nutrient interactions. We sought to determine the effects of pomegranate juice (a major source of antioxidants) consumption on prostate-specific antigen (PSA) progression in men with a rising PSA following primary therapy. EXPERIMENTAL DESIGN: A phase II, Simon two-stage clinical trial for men with rising PSA after surgery or radiotherapy was conducted. Eligible patients had a detectable PSA > 0.2 and < 5 ng/mL and Gleason score < or = 7. Patients were treated with 8 ounces of pomegranate juice daily (Wonderful variety, 570 mg total polyphenol gallic acid equivalents) until disease progression. Clinical end points included safety and effect on serum PSA, serum-induced proliferation and apoptosis of LNCaP cells, serum lipid peroxidation, and serum nitric oxide levels. RESULTS: The study was fully accrued after efficacy criteria were met. There were no serious adverse events reported and the treatment was well tolerated. Mean PSA doubling time significantly increased with treatment from a mean of 15 months at baseline to 54 months posttreatment (P < 0.001). In vitro assays comparing pretreatment and posttreatment patient serum on the growth of LNCaP showed a 12% decrease in cell proliferation and a 17% increase in apoptosis (P = 0.0048 and 0.0004, respectively), a 23% increase in serum nitric oxide (P = 0.0085), and significant (P < 0.02) reductions in oxidative state and sensitivity to oxidation of serum lipids after versus before pomegranate juice consumption. CONCLUSIONS: We report the first clinical trial of pomegranate juice in patients with prostate cancer. The statistically significant prolongation of PSA doubling time, coupled with corresponding laboratory effects on prostate cancer in vitro cell proliferation and apoptosis as well as oxidative stress, warrant further testing in a placebo-controlled study.
Administration, Oral↗
Transdermal delivery of tea catechins by electrically assisted methods.
Tea polyphenols, including (+)-catechin, (-)-epicatechin, and (-)-epigallocatechin-3-gallate (EGCG), have been shown to possess potent antioxidant and chemopreventive activities. The aim of this study was to assess the effects of electroporation, iontophoresis, and their combination on the transdermal delivery of tea catechins across porcine skin. The permeation characteristics were investigated using various analogues of catechins, pH values, and modes of electroporation and iontophoresis. The mechanisms by which these catechins were transported via the skin were elucidated by examining the electric conductivity, transepidermal water loss (TEWL), and fusion of stratum corneum lipid liposomes (SCLL). The isomers, (+)-catechin and (-)-epicatechin, showed different behaviors of skin permeation and local skin deposition with the electrically assisted methods. The results suggest evidence of selective skin absorption of (-)-epicatechin over (+)-catechin. A synergistic effect was detected for (+)-catechin but not for (-)-epicatechin after application of electroporation followed by iontophoresis. The presence of a gallic acid ester in the structure of EGCG significantly increased the skin uptake of catechins. However, a negligible amount of or no EGCG molecules permeated across the skin. The mechanisms involved in the enhancement of electroporation may be the skin reservoir effect and an increase in skin permeability. The TEWL profiles suggest that in addition to the force of electrorepulsion, the skin hydration effect and structural alterations may also have contributed to the enhancement by iontophoresis. Electroporation did not influence the skin barrier function, although the skin permeability increased according to the SCLL fusion study.
Administration, Cutaneous↗
In vitro anti-HCV activities of Saxifraga melanocentra and its related polyphenolic compounds.
The aim of this study was to search for new natural anti-HCV agents from Chinese herbal medicine. Bioactivity-guided extraction and isolation methods were used. Active part and pure compounds were obtained from ethanolic extract of Saxifraga melanocentra Franch. and their in vitro inhibitory activities (IC50) against HCV NS3 serine protease were tested by enzyme-linked immunosorbent assay. Results showed that the polyphenolic ethyl acetate part of the herbal extract was the most active, and from this 18 polyphenols representing active compounds were isolated and identified. IC50 values of these compounds and five related ones were obtained. A broad-degree of anti-HCV activity was observed among them in the following order: gallated esters of D-glucose and rutin (0.68-4.86 microM)> flavonoids (33.11-370.37 microM)> gallic acid and its methyl and ethyl esters, Bergenin and others (over 1000 microM). The most active compound was 1,2,3,4,6-penta-O-galloyl-beta-D-glucoside (0.68 microM). In conclusion, polyphenols were responsible for the anti-HCV constitution of S. melanocentra, and multigallated esters of D-glucose possessed the strongest inhibition against HCV NS3 serine protease and little cytotoxic effect, suggesting the potential use of these compounds for designing and developing drugs for treatment of the viral infection.
Animals↗
Effect of apple extracts on NF-kappaB activation in human umbilical vein endothelial cells.
The mechanisms by which foods, such as fruit, are able to reduce the risk of chronic disease are still unclear. Several fruit products, including apples and apple juice, that are flavonoid-rich are reported to increase antioxidant levels in human subjects. This is supported by the finding from our previous studies that the chronic consumption of apple juice by human subjects reduced ex vivo low-density lipoprotein (LDL) oxidation; we hypothesized that this was due to the flavonoid in the apple juice, which, as we reported earlier, reduced in vitro LDL oxidation. To further explore whether the mixture of flavonoids and other phytochemicals in apples are biologically relevant antioxidants, we tested the effects of this flavonoid-rich apple extract (AE) on oxidant-related pathways in a model of the endothelium: human umbilical vascular endothelial cells (HU-VECs). The effects of AE on oxidant-responsive (i.e., tumor necrosis factor [TNF]-alpha-induced) nuclear factor (NF)- kappaB signaling in cell culture were assessed in transfected HUVECs by using a construct that expressed luciferase under the control of NF-kappaB. Incubation of HUVEC for 24 hrs with up to 10 mM (as gallic acid equivalents) of AE demonstrated no cytotoxicity, as determined by lactate dehydrogenase release, caspase 3 activation, and apoptosis marker-based FACS analysis. AE after a 24-hr incubation period at either 200 or 2000 nM showed a complex pattern of decreased basal and TNF-alpha-stimulated NF-kappaB signaling (63% maximal decrease) as assessed by luciferase activity in the transfected HUVECs, as well as by reduced levels of IkappaBalpha protein phosphorylation detected by Western blot analysis. We suggest that AE downregulates NF-kappaB signaling and that this is indicative of an antioxidant effect of the flavonoids present in AE.
Cell Line↗
Antioxidant and cytotoxic properties of lyophilized beer extracts on HL-60 cell line.
An impressive number of studies have suggested that red wine can be considered the protective beverage of choice against chronic and degenerative pathologies. Only few and controversial data are available on a potential, similar role for beer, which represents a more cost-effective, safe, and widely available beverage. Starting from the evidence that many antioxidant compounds present in red wine are also present at similar or even higher concentrations in beers, we first screened 48 commercially available beers and selected one (Mrt-HP) with very high polyphenol concentration and antioxidant activity estimated by ferric reducing antioxidant power. We demonstrated that a lyophilized preparation of Mrt-HP beer was cytotoxic with respect to a beer with low polyphenolic content (Trt-LP) when assayed on HL-60 human leukemia cell line. We measured a 60% decrease in cell viability at a polyphenol concentration of 250 microM quercetin equivalents. We also demonstrated that Mrt-HP cytotoxicity was not an artifact due to cell growth conditions because addition of Mrt-HP extracts to cell medium generated peroxide levels indistinguishable from controls. By means of cytofluorimetric analysis of pre-G1 population and caspase 3 activation, we demonstrated that Mrt-HP extracts activated apoptosis in HL-60 cell line. Finally, we found that the concentration of quercetin, resveratrol, and gallic acid in Mrt-HP was 10, 4.6, and 4.6-fold higher, respectively, than in Trt-LP, suggesting that the presence of these molecules might be responsible for the observed cytotoxicity. These data, together with the low in vivo beer toxicity reported in the literature, suggest a possible chemopreventive role for this beverage that requires further studies in animal models.
Anticarcinogenic Agents↗
Berry phenolics: antimicrobial properties and mechanisms of action against severe human pathogens.
Antimicrobial activity and mechanisms of phenolic extracts of 12 Nordic berries were studied against selected human pathogenic microbes. The most sensitive bacteria on berry phenolics were Helicobacter pylori and Bacillus cereus. Campylobacter jejuni and Candida albicans were inhibited only with phenolic extracts of cloudberry, raspberry, and strawberry, which all were rich in ellagitannins. Cloudberry extract gave strong microbicidic effects on the basis of plate count with all studied strains. However, fluorescence staining of liquid cultures of virulent Salmonella showed viable cells not detectable by plate count adhering to cloudberry extract, whereas Staphylococcus aureus cells adhered to berry extracts were dead on the basis of their fluorescence and plate count. Phenolic extracts of cloudberry and raspberry disintegrated the outer membrane of examined Salmonella strains as indicated by 1-N-phenylnaphthylamine (NPN) uptake increase and analysis of liberation of [14C]galactose- lipopolysaccharide. Gallic acid effectively permeabilized the tested Salmonella strains, and significant increase in the NPN uptake was recorded. The stability of berry phenolics and their antimicrobial activity in berries stored frozen for a year were examined using Escherichia coli and nonvirulent Salmonella enterica sv. Typhimurium. The amount of phenolic compounds decreased in all berries, but their antimicrobial activity was not influenced accordingly. Cloudberry, in particular, showed constantly strong antimicrobial activity during the storage.
1-Naphthylamine↗
Role of calcium in prolactin-stimulated c-myc gene expression and mitogenesis in Nb2 lymphoma cells.
Receptor-activated transmembrane calcium flux has been implicated as a mediator of the actions of many growth factors and hormones. We examined the effects of PRL, calcium ionophores, and calcium antagonists on 45Ca2+ flux, c-myc gene expression, and DNA synthesis in the PRL-dependent rat Nb2 lymphoma cell line. PRL had no detectable effects on 45Ca2+ uptake or efflux, and the mitogenic effects of PRL could not be reproduced by the calcium ionophore A23187 alone or in combination with the tumor-promoting phorbol ester 12-O-tetra-decanoyl-phorbol-13 acetate (TPA). PRL, but not A23187 or TPA, stimulated c-myc gene expression in quiescent Nb2 cells. Exposure to PRL for brief periods (15 min to 4 h), followed by extensive washing, resulted in a time- and dose-dependent activation of DNA synthesis measured 16 h later. This activation was not blocked by addition of excess anti-PRL antiserum after the wash steps, indicating that the observed stimulation was not due to residual PRL. Despite the marked increase in DNA synthesis, removal of PRL after 4 h prevented mitosis, suggesting that PRL may be required throughout the cell cycle for Nb2 cell proliferation. Although continuous incubation with calcium antagonists resulted in a dose-dependent inhibition of PRL-stimulated DNA synthesis, activation of DNA synthesis by brief exposure to PRL was not inhibited by the presence of EGTA, calcium channel blockers (nifedipine, cobalt chloride), or calmodulin inhibitors (trifluoperazine, N-6-aminohexyl-5-chloronaphthalene sulfonamide). PRL-stimulated c-myc expression was attenuated, but not blocked, by the calcium channel antagonists. However, the putative intracellular calcium antagonist TMB-8 inhibited both c-myc expression and DNA synthesis in a dose-dependent manner (IC50 = 16 microM). Nb2 cells were sensitive to TMB-8 throughout G1 of the cell cycle, but inhibition of DNA synthesis was greatest when TMB-8 was present during the first 3 h of mitogen presentation, indicating a block in the transition from G0 to G1 of the cell cycle. The effect of TMB-8 suggests that release of a small intracellular calcium pool may mediate the early actions of PRL in Nb2 cells.
Animals↗
An extract of Lannea microcarpa: composition, activity and evaluation of cutaneous irritation in cell cultures and reconstituted human epidermis.
Lannea microcarpa (Anacardiaceae) is a tropical tree used in African folk medicine and commercial dermopharmaceutical formulations. Fractionation and analysis of its polar extract allowed the identification of 4'-methoxy-myricetin 3-O-alpha-L-rhamnopyranoside, myricetin 3-O-alpha-L-rhamnopyranoside, myricetin 3-O-beta-D-glucopyranoside, vitexin, isovitexin, gallic acid and epi-catechin, as the major constituents. In-vivo assay (the croton oil ear test in mice) showed that the extract had significant anti-inflammatory effect (ID50 = 900 microg cm(-2)) but ten times lower than that of indometacin (ID50 = 93 microg cm(-2)), the non-steroidal anti-inflammatory drug used as reference. Cytotoxicity and cutaneous irritation of the extract and its constituents were investigated. The crude extract and its major components did not affect cell viability in-vitro either in three different cultures (J774. A1, WEHI-164 and HEK-293) of cells grown in monolayers or in the reconstituted human epidermis (RHE, 3D model), nor did they cause release of pro-inflammatory mediators (IL-1alpha) or histomorphological modification of RHE.
Anacardiaceae↗
TMB-8 inhibits respiration and cyclic GMP formation in Dictyostelium discoideum.
The putative inhibitor of intracellular calcium mobilization, TMB-8 was found to be a powerful inhibitor of respiration in amoebae of Dictyostelium discoideum. Consequently, the previously reported effects of this drug on cyclic GMP formation induced by chemoattractants were reassessed. It was found that TMB-8 abolished both folate and cyclic AMP-mediated accumulation of cyclic GMP in D. discoideum amoebae and that addition of Ca2+ completely restored this response. The Ca2+ chelating agent EGTA did not mimic the effect of TMB-8. The effect on cyclic GMP formation, however, occurred only at a concentration of TMB-8 that was ten times that causing maximal inhibition of respiration, and inhibition of cyclic GMP formation was completely restored by addition of excess Ca2+, whereas inhibition of respiration was only partially restored. The data suggest that TMB-8 has more than one inhibitory action, and because of the differential sensitivity of respiration and cyclic GMP formation to this drug, and the differential antagonism of excess Ca2+, we conclude that the effect of TMB-8 on the cyclic GMP response is probably due to its effect on Ca2+ mobilization, rather than indirectly via its effects on respiration. However, we advise caution in interpretation of data using this inhibitor where the responses measured are prolonged, are energy-requiring or are not freely reversible by excess Ca2+.
Calcium Channel Blockers↗
Carbonic anhydrase inhibitors from the pericarps of Punica granatum L.
Seven highly active inhibitors against carbonic anhydrase (CA, EC 4.2.1.1), punicalin (2), punicalagin (3), granatin B (5), gallagyldilactone (7), casuarinin (8), pedunculagin (9) and tellimagrandin I (10), and four weakly active inhibitors, gallic acid (1), granatin A (4), corilagin (6) and ellagic acid (11), were isolated from the pericarps of Punica granatum L. (Punicaceae). They are ellagitannins. The type of inhibition by 3 and 7 using p-nitrophenyl acetate as a substrate, is noncompetitive. The structure-activity relationship of inhibitory effects on CA is discussed.
Animals↗
Kinetic studies on a sulfotransferase from Klebsiella K-36, a rat intestinal bacterium.
Sulfotransferase purified from Klebsiella K-36, a rat intestinal bacterium, stoichiometrically catalyzed the transfer of a sulfate group of phenylsulfate esters to phenolic compounds. One of the reaction products, p-nitrophenol (PNP), non-competitively inhibited the enzyme as to p-nitrophenylsulfate (PNS), a donor substrate, but competitively inhibited the enzyme as to an acceptor substrate, alpha-naphthol. The other reaction product, alpha-naphthol-O-sulfate, non-competitively inhibited the enzyme with regard to both these substrates. These kinetic data suggest that the sulfotransferase reaction proceeds according to an ordered bi bi reaction mechanism. The natural phenolic substances, gallic acid, quercetin, tannic acid, and serotonin were good substrates of K-36 sulfotransferase.
Animals↗
Inhibitory activities of (-)-epigallocatechin-3-O-gallate against topoisomerases I and II.
The substitution of gallic acid at the 3 position of (-)-epigallocatechin-3-O-gallate (EGCG) increased the inhibition against topoisomerase I from calf thymus gland and topoisomerase II from human placenta, and the substitution of a hydroxyl group at the 3' position increased the inhibition against the topoisomerase I. These results suggested that the 3 and 3' positions of the EGCG molecule play important roles in the process of inhibition of topoisomerases I and II. EGCG showed strong inhibition against topoisomerases I from wheat germ, calf thymus gland and Vero cells, and showed weak or no inhibition against topoisomerases I from carcinoma cells such as A549, HeLa and COLO 201 cells. EGCG differentially inhibited the topoisomerases I from different sources.
Animals↗
Evaluation of in vitro antimicrobial and in vivo cytotoxic properties of some novel titanium-based coordination complexes.
The aim of the present study was to determine the antimicrobial and cytotoxic activities of eight novel titanium(III) based coordination complexes [Ti(Pht)(2)(DL-serine)(2), S(1)], [Ti(Pht)(2)(glycine)(2), S(2))], [Ti(Pht)(2)(cystine)(2), S(3)], [Ti(Pht)(2)(DL-leucine)(2), S(4)], [Ti(Suc)(2)(L-leucine)(2), S(5)], [Ti(Suc)(2)(cystine)(2), S(6)], [Ti(Suc)(2)(cystein)(2), S(7)] and [Ti(Suc)(2)(DL-serine)(2), S(8)] against several gram-positive and -negative bacteria, fungi and brine shrimp nauplii. The investigation showed that almost all of the complexes were moderately active against tested bacteria and fungi at high concentration (200 microg/disc) compared with the standard antibiotic, amoxicillin and the antifungal agent, nystatin. In vivo lethality bioassay experiment showed that only S(7) and S(8) among the complexes had better cytotoxic effect than standard gallic acid. The LC(50) values of these two complexes were found to be 1.00 and 1.21 microg/ml, respectively. Thus the results suggest that only two complexes (S(7), S(8)) among the titanium(III) based coordination complexes show the anticancer properties comparable to the standard cytotoxic agent, and further studies of these two complexes may be helpful for their clinical implication.
Animals↗
Enzymatic sulfation of polyphenols related to tannins by arylsulfotransferase.
This report discusses a novel type of arylsulfotransferase (AST) which was derived from human intestinal bacterium sulfated polyphenolic compounds when p-nitrophenyl sulfate (PNS) was taken as a donor substrate. (+)-Catechin, (+/-)-catechin, (-)-epicatechin and (-)-epicatechin gallate were better substrates than tyramine. (-)-Epigallocatechin and (-)-epigallocatechin gallate were slightly worse substrates than tyramine. Although gallic acid was a bad substrate, alkyl gallate esters were better substrates than tyramine. The degree of acceptor specificity increased in proportion to the length of the alkyl group up to the carbon number of five. Pedunculagin, geraniin and corilagin were less effective than tyramine. Rosmarinic acid and penta-O-galloyl-beta-D-glucose were similarly well sulfated. Two products, 4'-monosulfate and 4',5-disulfate of (+)-catechin, were detected at a two-fold molar excess of PNS over (+)-catechin. When (+)-catechin-4'-monosulfate as an acceptor was enzymatically sulfated with PNS as a donor, only the 4',5-disulfate was produced. Thus, arylsulfotransferase was useful for the convenient preparation of sulfate esters of polyphenols at their specific hydroxyl groups.
Arylsulfotransferase↗