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PubMed1998

Antiinflammatory activity of Anthurium cerrocampanense Croat in rats and mice.

Aqueous (AE), ethanol (EE) and dichloromethane (DE) extracts from the whole plant of Anthurium cerrocampanense Croat, endemic to Panama, were assayed for antiinflammatory activity by carrageenan-induced rat paw edema and croton oil-induced mouse ear edema tests. The extracts were administered i.p. and topically, respectively. The best antiinflammatory activity in the carrageenan-induced rat paw edema test, was shown by DE (31% inhibition), which did not show any irritant effect in the peritoneal examination 4 h after administration of the extracts. Furthermore, the highest activity in the croton oil-induced mouse ear edema test was also exhibited by DE (93% inhibition). Since DE was the most effective of the extracts in both tests, it's activity was assessed in various inflammation models in rats. At 100 mg/kg, DE markedly inhibited inflammation produced by dextran (66.6% inhibition) and decreased weakly the edema induced by zymosan A, carrageenan and C16-platelet activation factor (C16-PAF) (33.2, 31.6 and 23.8%, respectively). At 50 mg/kg, DE only significantly reduced the swelling caused by dextran (36.2%). No effect was observed at the same doses in arachidonic acid-induced edema. A clear dose-related antiinflammatory activity of DE was seen in the croton oil-induced mouse ear edema test, and ED50 calculated was found to be 25.5 microg/ear. which was much lower than ED50 obtained for indomethacin (56.1 microg/ear).

Animals↗
PubMed2001

Biological screening of rain forest plot trees from Palawan Island (Philippines).

Study plots totaling 0.2 Ha were established in primary forest in the highlands of central Palawan Island, Philippines. Samples of various anatomical parts [typically leaf + twig (If/tw), stem bark (sb), and root (rt)] were collected from all tree species represented within the plots by individuals having a diameter at breast height > or = 10 cm. In all, 211 distinct samples were obtained from 68 tree species, representing 35 families (not including samples from 4 indeterminate species). Methanol extracts of these samples were tested in in vitro antiplasmodial, brine shrimp toxicity, and cytotoxicity assays. The following samples showed an IC50 < or = 10 microg/mL against either chloroquine-sensitive or chloroquine-resistant clones of Plasmodium falciparum: Acronychia laurifolia (sb), Agathis celebica (lf/tw), Aglaia sp. 1 (sb), Aglaia sp. 2 (lf/tw, rt), Bhesa sp. 1 (rt), Cinnamomum griffithii (lf/tw), Croton leiophyllus (rt), Dysoxylum cauliflorum (rt), Garcinia macgregorii (sb), Lithocarpus sp. 1 (rt, sb), Meliosma pinnata ssp. macrophylla (lf/tw, rt), Myristica guatteriifolia (lf/tw), Ochrosia glomerata (rt, sb), Swintonia foxworthyi (lf/tw), Syzygium sp. 1 (rt), Turpinia pomifera (rt), and Xanthophyllum flavescens (sb). Secondly, those samples which displayed > or = 50% immobilization of brine shrimp at 100 microg/mL were: Acronychia laurifolia (lf/tw/fruit, rt, sb), Agathis celebica (lf/tw, sb), Aglaia sp. 1 (lf/tw), Alphonsea sp. 1 (rt), Ardisia iwahigensis (lf/tw), Arthrophyllum ahernianum (lf/tw, rt, sb), Castanopsis cf. evansii (rt), Cinnamomum griffithii (lf/tw, rt), Croton argyratus (lf/tw), C. leiophyllus (lf/tw, rt), Dysoxylum cauliflorum (fruit, lf/tw, rt), Euonymus javanicus (rt), Glochidion sp. 1 (rt), Polyosma sp. 1 (rt), Symplocos polyandra (rt), Timonius gammillii (sb), and Xanthophyllum flavescens (rt). Lastly, samples which exhibited an IC50 < or = 20 microg/mL against one or more of the cancer cell lines employed (LU1, KB, KB-V1, P-388, LNCaP, or ZR-75-1) include: Acronychia laurifolia (lf/tw/fruit, rt, sb), Aglaia sp. 1 (sb), Aglaia sp. 2 (rt), Alphonsea sp. 1 (rt), Ardisia iwahigensis (lf/tw, rt, sb), Astronia cumingiana (sb), Croton argyratus (lf/tw, rt, sb), C. leiophyllus (lf/tw, rt), Dimorphocalyx murina (lf/tw, rt, sb), Lithocarpus caudatifolius (rt, sb), Litsea cf. sibuyanensis (rt), Syzygium cf. attenuatum (rt, sb), S. confertum (sb), Ternstroemia gitingensis (rt), and Ternstroemia sp. 1 (rt, sb).

Animals↗
PubMed1999

Characterization of the anaerobic propionate-degrading syntrophs Smithella propionica gen. nov., sp. nov. and Syntrophobacter wolinii.

A strain of anaerobic, syntrophic, propionate-oxidizing bacteria, strain LYPT (= OCM 661T; T = type strain), was isolated and proposed as representative of a new genus and new species, Smithella propionica gen. nov., sp. nov. The strain was enriched from an anaerobic digestor and isolated. Initial isolation was as a monoxenic propionate-degrading co-culture containing Methanospirillum hungateii JF-1T as an H2- and formate-using partner. Later, an axenic culture was obtained by using crotonate as the catabolic substrate. The previously described propionate-degrading syntrophs of the genus Syntrophobacter also grow in co-culture with methanogens such as Methanospirillum hungateii, forming acetate, CO2 and methane from propionate. However, Smithella propionica differs by producing less methane and more acetate; in addition, it forms small amounts of butyrate. Smithella propionica and Syntrophobacter wolinii grew within similar ranges of pH, temperature and salinity, but they differed significantly in substrate ranges and catabolic products. Unlike Syntrophobacter wolinii, Smithella propionica grew axenically on crotonate, although very slowly. Co-cultures of Smithella propionica grew on propionate, and grew slowly on crotonate or butyrate. Syntrophobacter wolinii and Syntrophobacter pfennigii grow on propionate plus sulfate, whereas Smithella propionica did not. Comparisons of 16S rDNA genes indicated that Smithella propionica is most closely related to Syntrophus, and is more distantly related to Syntrophobacter.

Acetates↗
PubMed1999

Sporobacterium olearium gen. nov., sp. nov., a new methanethiol-producing bacterium that degrades aromatic compounds, isolated from an olive mill wastewater treatment digester.

A strictly chemo-organotrophic, anaerobic bacterium was isolated from an olive mill wastewater treatment digester on syringate and designated strain SR1T. The cells were slightly curved rods, stained Gram-positive and possessed terminal spores. Strain SR1T utilized crotonate, methanol and a wide range of aromatic compounds including 3,4,5-trimethoxybenzoate (TMB), 3,4,5-trimethoxycinnamate (TMC), syringate, 3,4,5-trimethoxyphenylacetate (TMPA), 3,4,5-trimethoxyphenylpropionate (TMPP), ferulate, sinapate, vanillate, 3,4-dimethoxybenzoate, 2,3-dimethoxybenzoate, gallate, 2,4,6-trihydroxybenzoate (THB), pyrogallol, phloroglucinol and quercetin as carbon and energy sources. Acetate and butyrate were produced from aromatic compounds, methanol and crotonate whereas methanethiol (MT) was produced from methoxylated aromatic compounds and methanol. Strain SR1T had a G + C content of 38 mol% and grew optimally between 37 and 40 degrees C at pH 7.2 on a crotonate-containing medium. Phylogenetically, strain SR1T was a member of cluster XIVa of the Clostridiales group and shared a sequence similarity of 90% with Clostridum aminovalericum and Eubacterium fissicatena. Consequently, its precise neighbourliness to any one of them depended on the selection of strains of the cluster. On the basis of the phylogenetic and phenotypic evidence presented in this paper, the designation of strain SR1T as Sporobacterium olearium gen. nov., sp. nov. is proposed. The type strain is SR1T (= DSM 12504T).

Acetates↗
PubMed2004

Syntrophomonas curvata sp. nov., an anaerobe that degrades fatty acids in co-culture with methanogens.

A strict anaerobe (strain GB8-1(T)) that degraded straight-chain fatty acids with C(4)-C(18) in syntrophic association with methanogens was isolated from an up-flow anaerobic sludge blanket reactor treating beer wastewater. Strain GB8-1(T) degraded 1 mol butyrate into about 2 mol acetate and 1 mol (presumably) H(2) in co-culture with a methanogen. Neither branched-chain fatty acids nor benzoate could be degraded. Strain GB8-1(T) could grow on crotonate in pure culture and converted 1 mol crotonate to 0.5 mol butyrate and 1 mol acetate. Generation time was about 11 h when grown on crotonate at 37 degrees C. Fumarate, sulfate, thiosulfate, sulfur and nitrate could not serve as electron acceptors for strain GB8-1(T) to degrade butyrate. Cells of strain GB8-1(T) were curved rods with Gram-negative cell walls; no spores were observed. The DNA G+C content was 46.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain GB8-1(T) was related most closely to the fatty acid-oxidizing, syntrophic bacterium Syntrophomonas sapovorans DSM 3441(T); however, the relationship was not very close (95.4 % sequence similarity). Some phenotypic features also differentiated strain GB8-1(T) from Syntrophomonas sapovorans DSM 3441(T). Therefore, a novel species, Syntrophomonas curvata sp. nov., is proposed. The type strain is GB8-1(T) (=CGMCC 1.5010(T)=DSM 15682(T)).

Bacteria, Anaerobic↗
PubMed1987

Different cellular reaction patterns of epidermal Langerhans cells after application of contact sensitizing, toxic, and tolerogenic compounds. A comparative ultrastructural and morphometric time-course analysis.

BALB/c mice were treated with the irritants croton oil (0.5%, 20%), sodium lauryl sulfate (15%), and benzalkonium chloride (25%), the contact sensitizers 2,4-dinitrofluorobenzene (DNFB, 0.3%) and picryl chloride (PCl, 1%), and the tolerogen 2,4-dinitrothiocyanatebenzene (DNTB, 2%). All irritants used produced degenerative alterations of Langerhans cells (LCs). After application of 0.5% croton oil, however, this degeneration was preceded by an activation of the cells with increased number of mitochondria and enlargement of nuclei. The DNFB and PCl application in sensitizing doses to nonsensitized animals resulted in a cellular activation similar to that observed for 0.5% croton oil. In addition, these LCs showed enhanced adsorptive endocytosis as demonstrated by increased numbers of Birbeck granules and coated vesicles. The endocytotic activity was more pronounced in DNFB-sensitized animals. The DNTB at a concentration that induced tolerance to DNFB did not cause either cellular or endocytotic activation of LCs. These results demonstrate that the contact sensitizers DNFB and PCl induce characteristic cellular reaction patterns of LCs, which may be related to their sensitizing property.

Animals↗
PubMed1992

Induction of inflammatory cytokines in murine keratinocytes upon in vivo stimulation with contact sensitizers and tolerizing analogues.

In order to elucidate the role of keratinocytes (KCs) in the induction of contact sensitivity, we applied various contact sensitizers [2,4-dinitrofluorobenzene (DNFB), urushiol, 3-n-pentadecylcatechol (PDC), 4-ethoxymethylene-2-phenyloxazol-5-one (oxazolone)] and tolerizing compounds [2,4-dinitrothiocyanobenzene (DNTB), 5-methyl-3-n-pentadecyl-catechol (5-Me-PDC)] onto the earskin of non-sensitized Balb/c mice. In addition, we applied croton oil as a non-sensitizing, but stimulatory agent. Cytokine production was demonstrated by Northern blot hybridization of the total cellular RNA extracted from epidermal cells depleted by Langerhans cells and Thy 1+ dendritic cells using radiolabeled DNA probes encoding for the murine cytokines IL-1 alpha, -2, -3, -4, TNF alpha, IFN tau, GM-CSF and G-CSF. From all cytokines tested, TNF alpha and IL-1 alpha were markedly increased upon in vivo stimulation with contact sensitizers and also after application of croton oil. Both light and electron microscopic immunostaining with a polyclonal and monoclonal antibody demonstrated the presence of TNF alpha in the epidermis. This staining was most pronounced in KCs of the suprabasal epidermis upon application of contact sensitizers or croton oil, but not with tolerizing analogues. Using a functional assay significantly more TNF alpha was found in the supernatants of KCs treated in vitro with DNFB or LPS than with DNTB. GM-CSF was found in untreated epidermis as well as in stimulated cells. The results suggest that the sensitizing properties of contact sensitizers may partly be dependent on their ability to induce proinflammatory mediators. The induction and release of TNF alpha and IL-1 alpha in KCs by contact sensitizers may play an important role in the early response to immunogenic or inflammatory signals in vivo, whereby tolerance induction seems to be less dependent on these cytokines.

Animals↗
PubMed1987

Anti-inflammatory activity of a polysaccharidic fraction of Echinacea angustifolia.

The anti-inflammatory activity of a polysaccharidic fraction (EPF) obtained from Echinacea angustifolia roots has been examined using the carrageenan paw oedema and the croton oil ear test. EPF (0.5 mg kg-1 i.v.) almost inhibited the carrageenan-induced oedema over 8 h and furthermore, EPF, topically applied, inhibited mouse ear oedema induced by croton oil. EPF also reduced the leukocytic infiltration of the croton oil dermatitis, evaluated both as peroxidase activity and histologically. After topical application EPF appears to be slightly inferior in potency to indomethacin. The results suggest that the anti-inflammatory activity of E. angustifolia resides in its polysaccharidic content.

Administration, Topical↗
PubMed1989

Effects of Organic Acid Anions on the Growth and Metabolism of Syntrophomonas wolfei in Pure Culture and in Defined Consortia.

The effects of organic acid anions on the growth of Syntrophomonas wolfei was determined by varying the initial concentration of the acid anion in the medium. The addition of 15 mM acetate decreased the growth rate of a butyrate-catabolizing coculture containing Methanospirillum hungatei from 0.0085 to 0.0029 per hour. Higher initial acetate concentrations decreased the butyrate degradation rate and the yield of cells of S. wolfei per butyrate degraded. Inhibition was not due to the counter ion or the effect of acetate on the methanogen. Initial acetate concentrations above 25 mM inhibited crotonate-using pure cultures and cocultures of S. wolfei. Benzoate and lactate inhibited the growth of S. wolfei on crotonate in pure culture and coculture. Lactate was an effective inhibitor of S. wolfei cultures at concentrations greater than 10 mM. High concentrations of acetate and lactate altered the electron flow in crotonate-catabolizing cocultures, resulting in the formation of less methane and more butyrate and caproate. The inclusion of the acetate-using methanogen, Methanosarcina barkeri, in a methanogenic butyrate-catabolizing coculture increased both the yield of S. wolfei cells per butyrate degraded and the efficacy of butyrate degradation. Butyrate degradation by acetate-inhibited cocultures occurred only after the addition of Methanosarcina barkeri. These results showed that the metabolism of S. wolfei was inhibited by high levels of organic acid anions. The activity of acetate-using methanogens is important for the syntrophic degradation of fatty acids when high levels of acetate are present.

Journal Article↗
PubMed1987

Evaluation of premalignant and malignant lesions during the induction of mouse melanomas.

The objective of the present study was to evaluate the malignant and premalignant lesions that arise in C57BL/6 mice after treatment with 7,12-dimethylbenz(a)anthracene and croton oil. Tissues from 70 treated mice were evaluated by histological and transplantation techniques, and 17 (24%) were found to have malignant tumors. Eleven of the tumors were diagnosed as malignant melanomas, three as spindle cell sarcomas, and three as squamous cell carcinomas. The incidence of malignant melanomas (15.7%) in this group of mice was similar to that in our initial study on the induction of melanomas with 7,12-dimethylbenz(a)-anthracene and croton oil, in which two of 20 mice developed malignant melanomas. Mice that developed melanomas had been treated with croton oil for an average of 7 mo, and the mean latent period for tumor development was 11 mo. Seven of eight melanomas grew rapidly after transplantation to syngeneic C57BL/6 mice. Pigmented nevi and/or draining lymph nodes from nine of 11 mice with melanomas grew progressively after transplantation to athymic nude mice. Pooled nevi from one mouse with no apparent tumors grew into a histologically malignant melanoma after transplantation to a nude mouse. Nevi from three mice with sarcomas, one mouse with a carcinoma, and 42 tumor-free treated mice failed to grow in nude transplant recipients. Thus, only nevi from mice with either apparent or occult malignant melanomas exhibited progressive growth in nude mice. These results confirm that malignant melanomas can be induced in C57BL/6 mice at a regular, predictable rate and further indicate that this is an excellent system in which to study melanoma induction, progression, and therapy.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1984

[Quantitative determination of the irritating effect on human skin of butanol, octanol, acetaldehyde and crotonaldehyde].

A method was elaborated for quantitative assessment of the irritating effect of the solvents after a 24-hour contact with healthy subjects. The irritating effect of octanol is weaker, with statistical significance, than that of butanol. Croton aldehyde proved to be the strongest irritator. The threshold skin irritating concentrations are 12% octanol, 7.8% butanol, 1.2% acetaldehyde and 0.12% croton aldehyde in plant oil. The following allergic concentrations in plant oil are recommended for epicutaneous testing of subjects with occupational or every day home contact allergy versus paints, varnishes, glues, cleaning and defatting agents and anticorrosive preparations: 6% octanol, 4% butanol, 0.6% acetaldehyde and 0.06% croton aldehyde.

Acetaldehyde↗
PubMed1983

Strain-specific tumorigenesis in mouse skin induced by the carcinogen, 15,16-dihydro-11-methylcyclopenta[a]phenanthren-17-one, and its relation to DNA adduct formation and persistence.

The incidence of skin tumors has been studied in three strains of mice, namely, TO, C57BL, and DBA/2, after treatment with the carcinogen 15,16-dihydro-11-methylcyclopenta[a]phenanthren-17-one. After either a single dose followed by croton oil promotion or a continual dose of the carcinogen, tumors were observed in the TO and C57BL strains, with the TO mice having the shorter mean latent period. The DBA/2 mice, however, appeared to be resistant to tumor formation by either treatment. To understand the mechanism of resistance, several criteria have been investigated. Metabolism of the carcinogen was assessed in terms of the total DNA adduct formation and the pattern of individual adducts after separation by high-pressure liquid chromatography, and no major differences between the three strains was found. Similarly, the rates of disappearance of the individual adducts when measured over 14 days posttreatment were not strain specific. Persistent binding of the carcinogen after 2 months was found in all three strains and could be reduced markedly if croton oil was administered throughout this period. The ability of the phorbol esters to cause biochemical changes in both sensitive and resistant strains was indicated by the induction of ornithine decarboxylase in each of the three strains after treatment with either croton oil or its active component, 12-O-tetradecanoylphorbol-13-acetate.

Animals↗
PubMed1979

Dissociation of alpha-macrofetoprotein and alpha-fetoprotein production during experimental injury.

The concentrations of two major fetal serum proteins of the rat, alpha-macrofetoprotein (AMF) and alpha-fetoprotein (AFP) are measured following administration of croton oil, carbon tetrachloride, galactosamine or ethionine, and after partial hepatectomy. Greatly elevated serum concentrations of AMF are found after croton oil injection, following oral administration of CCl4, and after partial hepatectomy, but not after ethionine or galactosamine. Elevations of AFP occur after administration of hepatotoxic agents during the stage of restitutive proliferation and after exposure to the hepatocarcinogen ethionine, but not after croton oil. Therefore, elevations of AMF and AFP are clearly dissociated under certain conditions. In situations such as partial hepatectomy, after which elevations in both AMF and AFP occur, AMF appears before AFP. Therefore, the production of AMF and AFP appear to be under completely independent regulation in the adult.

Animals↗
PubMed1975

Susceptibility to primary irritants: age dependence and relation to contact allergic reactions.

Patch tests with three primary irritants were performed in 600 persons with eczema and in 33 healthy controls, The irritants assayed were: croton oil (20%) in mineral oil, thymoquinone (1%) in ethanol and crotonaldehyde (7.5%) plus sodium lauryl sulphate (4%) in aqua dest. The number of positive reactions to croton oil was found to decrease with age, while for thymoquinone and crotonaldehyde and for the total irritant score no age dependence was observed. No significant correlation was found between sensitization to common contact allergens and susceptibility to irritants. The incidence of positive reactions to common allergens proved to increase with age.

Adolescent↗
PubMed2000

Anticarcinogenicity potential of spinasterol isolated from squash flowers.

Spinasterol, an antimutagen, was isolated from squash flowers by solvent partitioning and repeated vacuum liquid chromatography. Spinasterol was then tested for its anticarcinogenic potential by using the mouse skin tumor assay. There was a 90% skin tumor incidence for the positive control group (DMBA + croton oil + acetone). At a concentration of 15.0 microg/0.2 ml acetone, spinasterol decreased the incidence of skin tumors by 55.6% and decreased the number of tumors by 65.0% when applied immediately after croton oil. Hence, spinasterol showed antitumorigenic potential. It is not a co-carcinogen nor a co-tumor promoter as there was no increase in the incidence of skin tumors after spinasterol application. Teratogenesis Carcinog. Mutagen. 20:99-105, 2000.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1975

The effect of radial radiotherapy on delayed hypersensitivity and the inflammatory response.

Delayed hypersensitivity to DNCB and the inflammatory response to croton oil wereevaluated in 144 and 121 patients respectively, prior ro and 3 to 6 months following curative radiotherapy. Eighty-one patients had in vitri lymphocyte transformation by PHA;59 (41%) were nonreactors to DNCB and 27 (22%) to croton oil; 29 of 59 (49%) initiallyreactive became anergic. Similiar improvement of the inflammatory response was obtained. Patients who became DNCB-reactive following radiotherapy had the same favorable prognosis as those who were initially reactive. Radiotherapy did not adversely affect either delayed hypersensitivity or the inflammatory response. There was a 50% decrease in PHA stimulation and lymphocyte count after treatment. No correlation was found between DNCB reactivity and lymphocyte transfermation prior to or following radiotherapy. The evaluation of the effect of radiotherapy on cell-mediated immunity depends on the tests used.

Animals↗
PubMed1985

Nuclear enlargement--an early change produced in mouse epidermis by carcinogenic chemicals applied topically in the presence of a promoter.

A series of 27 compounds, including 11 polycyclic hydrocarbons, 8 proximate carcinogens and 8 other compounds, were tested for their ability to induce epidermal nuclear enlargement in mouse skin. The materials were applied topically in methyl ethyl ketone containing 0.1% croton oil, repetitively for 3 days. Nuclear enlargement present on the fourth day was determined with the aid of a Quantiment image-analysing computer. The results obtained indicated a close correlation between the topical carcinogenicity of the test compounds and their ability to induce epidermal nuclear enlargement in the presence of croton oil.

Administration, Topical↗
PubMed1994

Novel fluorinated antiinflammatory steroid with reduced side effects: methyl 9 alpha-fluoroprednisolone-16-carboxylate.

In an effort to test the hypothesis that 9 alpha-fluorination of a steroidal antedrug would enhance receptor binding affinity and local antiinflammatory activity, without concomitantly increasing adverse systemic effects, a fluorinated analog, 10, of methyl 11 beta, 21-dihydroxy- 3,20-dioxo-1,4-pregnadiene-16 alpha-carboxylate (DP16CM, 1) was synthesized and evaluated. In the acute rat croton oil-induced ear edema bioassay, 10 was found to be twice as potent as 1. This increase in topical potency was consistent with enhanced binding affinity of 10, relative to 1. The IC50 values for displacement of [3H]dexamethasone from glucocorticoid receptors of rat hepatoma tissue culture cells were 0.16, 1.2, and 0.03 microM for 10, 1, and prednisolone, respectively. Following multiple topical ID50 applications of predniosolone, 1, and its new fluorinated analog, 10, in the rat subacute croton oil-induced ear edema bioassay, only prednisolone exhibited significant untoward effects, such as reduction in relative thymus and adrenal weights, plasma corticosterone levels, and normal body weight gain. Thus, while fluroination of 1 enhanced its topical potency, there was not a concomitant increase in untoward systemic effects. This lack of adverse systemic effects is ostensibly due to the presence of the metabolically labile 16-carboxylate ester moiety.

Administration, Topical↗