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At least 811 records · Page 45Linked to original sources
PubMed2004

Effect of ethanol extracts of three Chinese medicinal plants with laxative properties on ion transport of the rat intestinal epithelia.

The effects of ethanol extracts of three Chinese medicinal plants Dahuang (Rheum palmatum L.), Badou (Croton tiglium L.), and Huomaren (Cannabis sativa L.), on ion transport of the rat intestinal epithelia were studied. Rat intestinal epithelia mounted in an Ussing chamber attached with voltage/current clamp were used for measuring changes of the short-circuit current across the epithelia. The intestinal epithelia were activated with current raised by serosal administration of forskolin 5 microM. Ethanol extracts of the three plants all augmented the current additively when each was added after forskolin. In subsequent experiments, ouabain and bumetanide were added prior to ethanol extracts of these medicinal plants to determine their effect on Na(+) and Cl(-) movement. The results suggest that ethanol extracts of the three medicinal plants may affect the Cl(-) movement more directly than Na(+) movement in the intestinal epithelial cells. The results provide evidence for the pharmacologic mechanism of the three Chinese medicinal plants on the intestinal tract.

Animals↗
PubMed2006

Anti-inflammatory activity of crude extract and fractions of Nectandra falcifolia leaves.

The present study evaluated the effect of the crude extract of the leaves of Nectandra falcifolia (NEES) Castiglioni and its fractions in different experimental models of inflammation (paw edema, pleurisy, and ear edema). Carrageenan-induced edema of the paw and pleurisy were evaluated in Wistar rats (180-220 g), which were treated with different doses of the total extract (250, 500 mg.kg-1). Edema of the ear, induced by croton oil, and determination of myeloperoxidase activity were evaluated in Swiss mice (25-35 g). In this experiment, the crude extract of Nectandra falcifolia (Nf) (1.25, 2.5, 5.0, 7.5 mg) and the hexane, chloroform, ethyl-acetate and hydromethanol fractions (5.0 mg) were applied topically, immediately after application of the oil. The crude extract of Nf (500 mg.kg-1) significantly reduced edema of the paw compared to the control group. Similarly, at doses of 250 and 500 mg.kg-1 it significantly reduced the volume of pleural inflammatory exudate compared to the control animals. However, it did not change the number of migrated cells. At doses of 2.5, 5.0 and 7.5 mg, the crude extract significantly inhibited edema of the ear and the influx of neutrophils. The fractions from Nectandra falcifolia (hexane, chloroform, ethyl acetate and hydromethanol) also inhibited edema of the ear. Taken together, the results demonstrated that the crude extract and its fractions administered to animals orally or topically showed an anti-inflammatory effect.

Administration, Oral↗
PubMed2004

[Inhibitory effects of some traditional medicines on proliferation of HIV-1 and its protease].

In attempts to discover anti-HIV agents from natural sources, various traditional medicine extracts were tested for their inhibitory effects on HIV-1 proliferation and its protease. An extract of the seeds of Croton tiglium showed potent inhibitory effects on the proliferation of HIV-1. The active principle was determined to be phorbol esters. Several derivatives of phorbol ester were evaluated for inhibition of proliferation as well as activation of protein kinase C (PKC). Of these compounds, 12-O-acetylphorbol 13-decanoate (6) showed the most potent inhibition of proliferation without activating PKC. Some triterpenes from the stems of Cynomorium songaricum and the woody part of Xanthoceras sorbifolia showed inhibitory activity against HIV-1 protease. Various derivatives of oleanolic acid were synthesized and evaluated for their inhibitory activity against HIV-1 protease. Their inhibitory mechanism was also investigated.

Croton↗
PubMed1998

Local anti-inflammatory activity and systemic side effects of NM-135, a new prodrug glucocorticoid, in an experimental inflammatory rat model.

The local anti-inflammatory activity and systemic side effects of NM-135 (6alpha,9-difluoro-11beta-hydroxy-16alpha-methyl-21[[2 ,3,4,6-tetrakis-O-(4-methylbenzoyl)-beta-D-glucopyranosyl]oxy]-pregna-1, 4-diene-3,20-dione) in croton oil-induced granuloma pouches and ear edema in rats were studied. The local anti-inflammatory activity of NM-135 was stronger than that of betamethasone 17-valerate (BV). As to systemic side effects, BV and diflucortolon valerate (DFV) caused thymolysis at the doses required for the anti-inflammatory activity. In contrast, no clear systemic side effect was observed in rats administered NM-135 at the dose producing the anti-inflammatory activity. These results suggest that NM-135 is a drug exhibiting a high degree of dissociation between the local anti-inflammatory activity and systemic side effects.

Animals↗
PubMed2003

Characteristics of an anaerobic, syntrophic, butyrate-degrading bacterium in paddy field soil.

The number of syntrophic butyrate-degrading bacteria in a flooded paddy field soil was 1.7 x 10(3) MPN/g dry soil. Butyrate was degraded to acetate and methane when paddy soils were incubated anaerobically with the addition of butyrate. However, butyrate degradation was completely suppressed by the addition of the specific inhibitor of methanogenesis, 2-bromoethanesulfonate (BES) to the soil. A hydrogen-using methanogen, strain TM-8, was isolated from flooded paddy field soil. Strain TM-8 was identified as Methanobacterium formicicum based on its physiology and phylogeny. Syntrophic butyrate-degrading bacteria were enumerated and isolated using strain TM-8. A syntrophic butyrate-degrading bacterium, strain TB-6, was isolated in coculture with strain TM-8 from paddy soil. The strain was Gram-negative, had curved rods, and grew on crotonate. Sulfate was not used as an electron acceptor. Strain TB-6 was closely related to S. wolfei subsp. wolfei. The relation between strain TB-6 and the members of Syntrophomonas are discussed.

Bacteria, Anaerobic↗
PubMed2003

Host plant use among closely related Anaea butterfly species (Lepidoptera, Nymphalidae, Charaxinae).

There is a great number of Charaxinae (Lepidoptera: Nymphalidae) species in the tropics whose larvae feed on several plant families. However the genus Anaea is almost always associated with Croton species (Euphorbiaceae). This work describes patterns of host plant use by immature and adult abundance on different vertical strata of sympatric Anaea species in a forest of Southeastern Brazil. Quantitative samples of leaves were taken in April/1999 and May/2000 to collect eggs and larvae of four Anaea species on C. alchorneicarpus, C. floribundus and C. salutaris in a semideciduous forest. Sampled leaves were divided into three classes of plant phenological stage: saplings, shrubs and trees. The results showed that the butterfly species are segregating in host plant use on two scales: host plant species and plant phenological stages. C. alchorneicarpus was used by only one Anaea species, whereas C. floribundus was used by three species and C. salutaris by four Anaea species. There was one Anaea species concentrated on sapling, another on sapling/shrub and two others on shrub/tree leaves. Adults of Anaea were more frequent at canopy traps but there were no differences among species caught in traps at different vertical positions. This work supplements early studies on host plant use among Charaxinae species and it describes how a guild of closely related butterfly species may be organized in a complex tropical habitat.

Animals↗
PubMed2006

Medicinal plants from Peru: a review of plants as potential agents against cancer.

Natural products have played a significant role in drug discovery and development especially for agents against cancer and infectious disease. An analysis of new and approved drugs for cancer by the United States Food and Drug Administration over the period of 1981-2002 showed that 62% of these cancer drugs were of natural origin. Natural compounds possess highly diverse and complex molecular structures compared to small molecule synthetic drugs and often provide highly specific biological activities likely derived from the rigidity and high number of chiral centers. Ethnotraditional use of plant-derived natural products has been a major source for discovery of potential medicinal agents. A number of native Andean and Amazonian medicines of plant origin are used as traditional medicine in Peru to treat different diseases. Of particular interest in this mini-review are three plant materials endemic to Peru with the common names of Cat's claw (Uncaria tomentosa), Maca (Lepidium meyenii), and Dragon's blood (Croton lechleri) each having been scientifically investigated for a wide range of therapeutic uses including as specific anti-cancer agents as originally discovered from the long history of traditional usage and anecdotal information by local population groups in South America. Against this background, we present an evidence-based analysis of the chemistry, biological properties, and anti-tumor activities for these three plant materials. In addition, this review will discuss areas requiring future study and the inherent limitations in their experimental use as anti-cancer agents.

Animals↗
PubMed1975

Initiation-promotion skin carcinogenesis and immunological competence.

The immune competence of mice during initiation-promotion skin carcinogenesis was determined by skin allograft rejection and lymphocyte mitogenesis. The carcinogen 7, 12-dimethylbenzanthracene inhibited the cellular immune competence of mice while lymphocytes from croton oil treated mice had enhanced PWM response. Chlorphenesin, a stimulator of cellular immunity, was found to inhibit tumorigenesis in initiation-promotion skin carcinogenesis when injected during promotion.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed2001

Neutral endopeptidase terminates substance P-induced inflammation in allergic contact dermatitis.

Sensory nerve-derived neuropeptides such as substance P demonstrate a number of proinflammatory bioactivities, but less is known about their role in inflammatory skin disease. The cell surface metalloprotease neutral endopeptidase (NEP) is the principal proteolytic substance P-degrading enzyme. This study tests the hypothesis that the absence of NEP results in dysregulated inflammatory skin responses. The effector phase of allergic contact dermatitis (ACD) responses was examined in NEP(-/-) knockout and NEP(+/+) wild-type mice and compared with the irritant contact dermatitis response in these animals. NEP was found to be normally immunolocalized in epidermal keratinocytes and dermal blood vessels. The ACD ear swelling response was 2.5-fold higher in animals lacking NEP and was accompanied by a significant increase in plasma extravasation and infiltration of inflammatory leukocytes. The augmented ACD response in NEP(-/-) animals was abrogated by either administration of a neurokinin receptor 1 antagonist or by repeated pretreatment with topical capsaicin. Similar to NEP(-/-) mice, the acute inhibition of NEP in NEP(+/+) animals resulted in an augmented ACD response. In contrast to the ACD responses, little differences were observed in the irritant contact dermatitis response of NEP(-/-) compared with NEP(+/+) animals after epicutaneous application of the skin irritants croton oil or SDS. Thus, these results indicate that NEP and cutaneous neuropeptides have a significant role in the pathogenesis of ACD.

Administration, Cutaneous↗
PubMed2002

An aspirin-triggered lipoxin A4 stable analog displays a unique topical anti-inflammatory profile.

Lipoxins and 15-epi-lipoxins are counter-regulatory lipid mediators that modulate leukocyte trafficking and promote the resolution of inflammation. To assess the potential of lipoxins as novel anti-inflammatory agents, a stable 15-epi-lipoxin A(4) analog, 15-epi-16-p-fluorophenoxy-lipoxin A(4) methyl ester (ATLa), was synthesized by total organic synthesis and examined for efficacy relative to a potent leukotriene B(4) (LTB(4)) receptor antagonist (LTB(4)R-Ant) and the clinically used topical glucocorticoid methylprednisolone aceponate. In vitro, ATLa was 100-fold more potent than LTB(4)R-Ant for inhibiting neutrophil chemotaxis and trans-epithelial cell migration induced by fMLP, but was approximately 10-fold less potent than the LTB(4)R-Ant in blocking responses to LTB(4). A broad panel of cutaneous inflammation models that display pathological aspects of psoriasis, atopic dermatitis, and allergic contact dermatitis was used to directly compare the topical efficacy of ATLa with that of LTB(4)R-Ant and methylprednisolone aceponate. ATLa was efficacious in all models tested: LTB(4)/Iloprost-, calcium ionophore-, croton oil-, and mezerein-induced inflammation and trimellitic anhydride-induced allergic delayed-type hypersensitivity. ATLa was efficacious in mouse and guinea pig skin inflammation models, exhibiting dose-dependent effects on edema, neutrophil or eosinophil infiltration, and epidermal hyperproliferation. We conclude that the LXA(4) and aspirin-triggered LXA(4) pathways play key anti-inflammatory roles in vivo. Moreover, these results suggest that ATLa and related LXA(4) analogs may have broad therapeutic potential in inflammatory disorders and could provide an alternative to corticosteroids in certain clinical settings.

Administration, Cutaneous↗
PubMed2003

Modulation of cutaneous inflammation by angiotensin-converting enzyme.

Cutaneous neurogenic inflammation is a complex biological response of the host immune system to noxious stimuli. Present evidence suggests that zinc metalloproteases may play an important role in the regulation of neurogenic inflammation by controlling the local availability of neuropeptides, such as substance P (SP), that are capable of initiating or amplifying cutaneous inflammation after release from sensory nerves. To address the hypothesis that the dipeptidyl carboxypeptidase angiotensin-converting enzyme (ACE) is capable of modulating skin inflammation, we have analyzed murine allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD) using wild-type C57BL/6J (ACE(+/+)) or genetically engineered mice with a heterozygous deletion of somatic ACE (ACE(+/-)). In 2,4-dinitro-1-fluorobenzene-sensitized ACE(+/-) mice, ACD was significantly augmented in comparison to ACE(+/+) controls as determined by the degree of ear swelling after exposure to hapten. Likewise, systemic treatment of ACE(+/+) mice with the ACE inhibitor captopril before sensitization or elicitation of ACD significantly augmented the ACD response. In contrast, local damage and neuropeptide depletion of sensory nerves following capsaicin, injection of a bradykinin B(2), or a SP receptor antagonist before sensitization significantly inhibited the augmented effector phase of ACD in mice with functionally absent ACE. However, in contrast to ACD, the response to the irritant croton oil was not significantly altered in ACE(+/-) compared with ACE(+/+) mice. Thus, ACE by degrading bradykinin and SP significantly controls cutaneous inflammatory responses to allergens but not to irritants, which may explain the frequently observed exacerbation of inflammatory skin disease in patients under medication with ACE inhibitors.

Administration, Cutaneous↗
PubMed1978

A32390A, a new biologically active metabolite. I. Discovery and fermentation studies.

A32390A is an isonitrile-containing derivative of diacyl D-mannitol. The compound is produced in fermentation as the major component of a metabolic complex known as A32390. A32390A inhibits dopamine-beta-hydroxylase reduces heart and adrenal norepinephrine levels, lowers blood pressure in hypertensive rats, and possesses antibiotic activity vs. Gram-positive bacteria and fungi, including Candida albicans. A32390 is produced in submerged culture by a mold, a species of Pyrenochaeta, NRRL-5786. Glucose and sucrose are among the best carbon sources for the biosynthesis of A32390. Mannitol, although a substituent of the A32390A molecule, supports little or no biosynthesis of the compound when employed as the major carbon source for the fermentation. The addition of crotonic acid derivatives. ethanol, or L-histidine to the fermentation medium enhances the level of A32390 produced.

Alcohols↗
PubMed1989

Processed Aloe vera administered topically inhibits inflammation.

Aloe vera preparations were evaluated for topical anti-inflammatory activity using the croton oil-induced edema assay. The results show that small amounts of A. vera given topically will inhibit inflammation induced by a moderate amount of irritant. In general, the decolorized Aloe was more effective than the colorized Aloe (with anthraquinone). A 47.1% inhibition of inflammation was obtained by 5% decolorized irradiated Aloe. These results may be used as a baseline to assess the biologic activity of A. vera in the treatment of inflammation by podiatric physicians.

Administration, Topical↗
PubMed1994

Aloe vera, hydrocortisone, and sterol influence on wound tensile strength and anti-inflammation.

Aloe vera at doses of 100 and 300 mg/kg daily for 4 days blocked the wound healing suppression of hydrocortisone acetate up to 100% using the wound tensile strength assay. This response was because of the growth factors present in A. vera masking the wound healing inhibitors such as sterols and certain amino acids. The sterols showed good anti-inflammatory activity (-36%) in reducing the croton oil-induced ear swelling. This activity displayed a dose-response relationship.

Aloe↗
PubMed1978

Effect of deoxycholic acid on 7,12-dimethylbenz(a)anthracene-induced, two-stage mouse skin carcinogenesis.

The effect of deoxycholic acid on 7,12-dimethylbenz(a)anthracenecroton oil carcinogenesis in mouse skin was tested. Painting deoxycholic acid in addition to croton oil during promotion resulted in the earlier appearance of tumors, a greater tumor incidence, and a larger number of tumors per animal. DMBA initiation followed by either deoxycholic acid or solvents during the promotion period produced no tumors. Animals receiving deoxycholic acid or solvents alone developed no tumors.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1999

Primary immune response in skin and skin-associated lymphoid tissue of interleukin-4 transgenic mice.

The interleukin-4 transgenic mice investigated here exhibit a ubiquitous expression of interleukin-4 in all organs, including the skin. In this study, the induction phase of oxazolone-induced local primary contact hypersensitivity and croton oil-induced irritant contact dermatitis in transgenic and wild-type mice was analysed. Compared to wild-type mice, the transgenic mice showed a decreased activation of the skin-draining lymph nodes but a strong hyperreactivity in the skin after topical sensitisation. In contrast to this, both the transgenic and the wild-type mice developed a strong and comparable inflammatory skin reaction after topical irritation. A striking increased expression level of tumour necrosis factor-alpha and macrophage inflammatory protein-2 genes were found in the skin of the transgenic mice during primary local contact hypersensitivity, while both the transgenic and the wild-type mice developed comparable expression levels of these cytokines during irritant contact dermatitis. Compared to wild-type mice, a strongly enhanced expression level of interleukin-6 transcripts derived from epidermal antigen presenting cells were detected in the skin of IL-4 transgenic mice, whereas in the skin-draining lymph nodes of transgenic mice significantly lower levels were detected. We conclude that the migration of epidermal antigen-presenting cells towards the skin-draining lymph nodes is reduced in transgenic mice, which could be due to the different cytokine balance in these mice strains. The atypical irritant-like reaction observed in transgenic mice after topical sensitisation is a phenomenon comparable to atopic diseases and therefore this transgenic strain might be a helpful model for investigating the immunopathophysiological features of these diseases.

Animals↗
PubMed1999

Localization of GABA receptor rho 2 and rho 3 subunits in rat brain and functional expression of homooligomeric rho 3 receptors and heterooligomeric rho 2 rho 3 receptors.

Ionotropic GABA receptors that are composed of rho subunits act to gate bicuculline-insensitive Cl- currents. Reverse transcription-polymerase chain reaction analysis revealed that the expression of rho 2 mRNA in adult rat brain was approximately eight times higher than mRNA in the rat brain at embryonic day 16, while that of rho 3 in the embryonic brain was approximately six times higher than in the adult brain. In the adult rat brain the rho 3 mRNA was present in the mesencephalon, hippocampus, cerebellum, thalamus and basal ganglia. In situ hybridization has been used to demonstrate the presence of rho 2 mRNA in the hippocampal CA1 region of the 8-day-old rat, and in the CAl region of the hippocampus, lateral geniculate nucleus, superficial gray layer of the superior colliculus and the pars compacta of the substantia nigra of the adult rat. When the homooligomeric rho 3 receptors were expressed in Xenopus oocytes, applications of agonists induced ionic currents. The order of potency of the agonists was muscimol > GABA = trans-4-amino-crotonic acid > cis-4-aminocrotonic acid. The ionic currents induced by GABA were blocked by picrotoxinin and Zn2+ in dose-dependent manner. In heterooligomeric rho 2 rho 3 receptors, picrotoxinin sensitivity was significantly reduced.

Amino Acid Sequence↗
PubMed1997

[The anti-inflammatory effects of superoxide dismutase].

This paper reports the anti-inflammatory effects of superoxide dismutase (SOD) from pig blood on inflammatory animal models. The experimental results have shown that SOD has significant anti-inflammatory effects. It inhibited carrageenin-induced foot-edema and croton oil induced granulation tissue edema of rats. It also inhibited arthritis induced by egg serum and Freund's adjuvant in rats. The effects were significantly dose-dependent.

Animals↗