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At least 973 records · Page 54Linked to original sources
PubMed2000

Novel steroid spiro enones: condensation of prednisolone derivatives with diethyl oxalate.

In a continuing effort to discover potent anti-inflammatory steroids without systemic side effects, diethyl oxalate was condensed with the 17beta-ketol side chain of prednisolone derivatives. Prednisolone gave the most interesting result in forming a novel spiro enone with alpha-hydroxy and beta-carboxylic ester substitutions, and a facile one-pot procedure has been established for the synthesis of this highly functionalized spiro enone structure. The spiro products were tested for their binding potency to the RAW 264.7 macrophage glucocorticoid receptor, for their effect on LPS-induced nitric oxide generation in RAW 264.7 cells, and for their inhibition of rats ear edema induced by croton oil. The new compounds showed weak activities in all of the bioassays. Because the corresponding acid metabolites of two representative spiro enone esters gave no activity in either the binding assay or the nitric oxide generation test, the novel steroids are probably antedrugs. The reduced potency as compared to their parent compounds suggests that the rigid spiro structure is unfavorable to anti-inflammatory activities. Molecular modeling studies confirm that the spiro enones adopt a rigid planar geometry with the ester group in the plane.

Animals↗
PubMed2000

Potential antitermite compounds from Juniperus procera extracts.

Thin layer chromatography (TLC) analysis revealed that destructive distillation of Juniperus procera tree gave ten major components, whereas Croton megalocarpus tree yielded five components. This was confirmed by gas chromatography (GC). The components were isolated by column chromatography and analysed using infrared, ultra-violet, visible and mass spectroscopy (MS) techniques. The whole extract was about 30.3% of the starting material (sawdust) and consisted of 77.5% water and 22.5% oily reddish-brown layer. The extracts had alcoholic and phenolic compounds together with acids. Cedrol, a tertiary tricyclic alcohol, was found to be in the greatest proportion in the oily layer. IR spectra with a peak beyond 3000 cm(-1), UV-VIS absorption maxima at 230 nm and mass spectra with m/e 204 suggested the presence of cedrene in the extract.

Animals↗
PubMed1998

Studies on the endothelin-1-induced contraction of rat granulation tissue pouch mediated by myofibroblasts.

A granulation tissue pouch, mostly composed of myofibroblasts, was prepared by injecting rats subcutaneously with croton oil. The contraction of the granulation tissue pouch caused by endothelin-1 (ET-1) and the effects of the ET receptor antagonists, BQ123 and BQ788 on it were thus examined. ET-1 produced contractions in a dose-dependent manner. Pretreatment with BQ123, an ETA receptor selective antagonist, shifted the dose-response curve to the right, whereas pretreatment with BQ788, an ETB receptor selective antagonist, showed little effect. IRL1620, an ETB receptor selective agonist, did not cause any contraction in the granulation tissue pouch. The existence of both ETA and ETB receptors in the granulation tissue pouch and in cultured myofibroblasts was demonstrated by RT-PCR. Intracellular Ca2+ mobilization in Fura-2/acetyl-methoxy ester loaded cultured myofibroblasts isolated from the granulation tissue was also examined. ET-1 produced a transient increase in [Ca2+]i followed by a sustained elevation of [Ca2+]i, whereas IRL1620 caused only a transient peak. These results suggest that the ET-1 induced contraction of granulation tissue is mainly mediated through the mobilization of Ca2+ from the extracellular space caused by stimulation with ETA receptor.

Animals↗
PubMed1983

Photocarcinogenesis, skin cancer, and aging.

Nonmelanoma skin cancers, like most malignancies, increase in incidence with increasing age. However, in general they are not due to the aging process but are primarily due to solar radiation. Clinically, squamous cell carcinomas and basal cell epitheliomas are the most common cancers that occur in the Caucasian population in the United States. The role of radiation from the sun was suggested by a number of astute clinical observations reported around 1900 and subsequently has been established by epidemiologic and experimental studies. Action spectrum evaluations indicate that the ultraviolet B (UVB) rays are the most carcinogenic. However, recent studies indicate that the UVA rays can augment the cancer-producing effects of UVB rays. Other physical stimuli, including heat and wind, can also accelerate UVB carcinogenesis. Chemicals such as the polycyclic hydrocarbons, the nitrosoureas, and nitrogen mustard have an additive carcinogenic effect with UVB radiation. Also, some chemicals such as croton oil, the phorbol ester--TPA, and all-trans-retinoic (RA) acid can promote UVB-initiated carcinogenesis. RA can also inhibit UVB-induced cancer formation. The role of the immune status has received a great deal of attention. Both in experimental and clinical situations, nonspecific immune suppression results in increased cancer formation. Also, recent studies indicate that a specific T cell suppressor population can be induced in experimental animals with UVB which will inhibit rejection of tumors produced by UVB radiation. Finally, damage to DNA by UVB radiation is well established. Studies with the genetic disease xeroderma pigmentosum support the concept that such damage, if not repaired, will lead to cancer formation. It also has been suggested that unrepaired damage to deoxyribonucleic (DNA) and other macromolecules is at least in part responsible for the aging process in general.

Aging↗
PubMed1989

Topical all-trans-retinoic acid prevents corticosteroid-induced skin atrophy without abrogating the anti-inflammatory effect.

We tested the ability of all-trans-retinoic acid to prevent corticosteroid-induced skin atrophy without lessening the anti-inflammatory effect of the steroids. Histologic study and skin-fold thickness in hairless mice treated topically with various steroids, followed by topical all-trans-retinoic acid, were used to measure prevention of atrophy. By both assessments, all-trans-retinoic acid prevented atrophy. Noninterference with the anti-inflammatory property of steroids was tested in a phorbol ester-induced mouse ear edema model and by histologic assessment of croton oil-induced inflammation of mouse dermis. We found that all-trans-retinoic acid did not interfere with steroid suppression of either edema or dermal inflammation. Thus all-trans-retinoic acid was effective in preventing steroid-induced atrophy without affecting the steroid's anti-inflammatory property.

Administration, Topical↗
PubMed2003

Comparative cytotoxicity of dimethylamide-crotonin in the promyelocytic leukemia cell line (HL60) and human peripheral blood mononuclear cells.

Dehydrocrotonin (DHC) is a diterpene lactone obtained from Croton cajucara (Sacaca). Dimethylamide-crotonin (DCR), a DHC derivative, has a similar inhibitory effect on leukemic HL60 cells than its parent compound evaluated by different endpoints of cytotoxicity. No cytotoxicity or morphological alterations associated with apoptosis were detected in human peripheral blood mononuclear cells (PBMC) after treatment with up to 400 micro M DCR in presence of phytohemaglutinin (5 micro g/ml). Based on morphological changes and the pattern of DNA fragmentation, DHC and DCR were found to induce apoptosis and terminal differentiation (assessed by nitro blue tetrazolium reduction) in HL60 cells, but these compounds did not show any toxic effect in PBMC. Thus, DCR and DHC inhibit HL60 cell growth in vitro partly by inducing apoptosis and cell differentiation, but does not cause serious damage to immune cells according to our experimental conditions.

Antineoplastic Agents, Phytogenic↗
PubMed2003

Role of GABA A and GABA B receptors in GABA-induced inhibition of rat red nucleus neurons.

We investigated GABA receptor subtypes mediating GABA-induced inhibition of red nucleus (RN) neuronal firing recorded extracellularly from anaesthetized rats. GABA response was mimicked by the GABA(A) agonists muscimol and isoguvacine in all cases and was partially blocked by the GABA(A) antagonist bicuculline. The GABA(B) agonist baclofen induced a long-lasting inhibition in 84% of cells. Neurons responding to either GABA(A) or GABA(B) agonists were equally distributed within the RN. The GABA(C) receptor agonist cis-amino-crotonic acid (CACA) did not modify RN neuronal firing; at high doses CACA occasionally induced inhibition abolished by bicuculline and thus mediated by GABA(A) receptors. We conclude that the inhibitory effects of GABA in the RN are mediated by both GABA(A) and GABA(B) receptors, whereas GABA(C) receptors are not involved.

Action Potentials↗
PubMed2001

Topical anti-inflammatory activity of Salvia officinalis L. leaves: the relevance of ursolic acid.

Salvia officinalis L. leaves, obtained from four plant populations of different origin, were investigated for their topical anti-inflammatory properties. The n-hexane and the chloroform extracts dose-dependently inhibited the Croton oil-induced ear oedema in mice, the chloroform extracts being the most active. By contrast, the methanol extracts showed a very low effect and the essential oil was inactive. Chemical and pharmacological investigation of the most potent chloroform extract, issued from an autochthonous sage population grown in the submediterranean climatic region of Slovenia, revealed ursolic acid as the main component involved in its anti-inflammatory activity. The anti-inflammatory effect of ursolic acid (ID50 = 0.14 microMoles/cm2) was two fold more potent than that of indomethacin (ID50 = 0.26 microMoles/cm2), which was used as a reference non-steroidal anti-inflammatory drug (NSAID). The content of ursolic acid in sage and sage-based remedies for the topical treatment of inflammatory diseases is proposed as a parameter for quality control purposes.

Administration, Topical↗
PubMed2001

Effect of Withania somnifera on DMBA induced carcinogenesis.

Administration of an extract of Withania somnifera was found to reduce two stage skin carcinogenesis induced by DMBA (dimethyl benzanthracene) and croton oil. Withania somnifera was administered at a concentration of (20 mg/dose/animal i.p.) consecutively on 5 days prior to DMBA administration and continued twice weekly for 10 weeks. After the 180th day of carcinogen administration, all of the animals developed papilloma in the control group whereas only six out of 12 animals developed papilloma in the treated group. A total of 11 papillomas were found in the control group while only six developed them in the Withania somnifera treated group. Enzyme analysis of skin and liver showed significant enhancement in antioxidant enzymes such as GSH, GST, Glutathione peroxides and Catalases in Withania somnifera treated group when compared with the control. The elevated level of lipid peroxide in the control group was significantly inhibited by Withania somnifera administration. These studies indicate that Withania somnifera could reduce the papilloma induced alterations to the antioxidant defense systems.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed2002

Hepatoprotective activity of two plants belonging to the Apiaceae and the Euphorbiaceae family.

The different extracts of Apium graveolens Linn. (Apiaceae) and Croton oblongifolius Roxb. (Euphorbiaceae) were tested for their hepatoprotective activity against CCl(4) induced hepatotoxicity in albino rats. The degree of protection was measured by using biochemical parameters like serum transaminases (SGOT and SGPT), alkaline phosphatase, total protein and albumin. The methanolic extracts showed the most significant hepatoprotective activity comparable with standard drug silymarin. Other extracts namely petroleum ether and acetone also exhibited a potent activity.

Animals↗
PubMed2002

Assessment of the antihypertensive and vasodilator effects of ethanolic extracts of some Colombian medicinal plants.

The antihypertensive and vasodilator effects of ethanolic extracts prepared from Calea glomerata Klatt, Croton schiedeanus Schlecht, Curatella americana L., Lippia alba (Mill)n N.E.Br. and Lupinus amandus, which are medicinal plants used in Colombian folk medicine for the treatment of hypertension, were assayed both in SHR and Wistar rats and in rat isolated aortic rings. At a dose of 20 mg/kg, intravenous bolus administration of the ethanolic extracts, from C. schiedeanus, C. americana and L. amandus showed significant antihypertensive activity in SHR, C. schiedeanus being the most active. C. schiedeanus elicited dose-dependent decreases in mean arterial pressure and heart rate (5-100 mg/kg, i.v.) in SHR but 200 mg/kg administered orally did not show any significant effects, even after 3 h of observation. In intact rat aortic rings, ethanolic extracts from C. schiedeanus and Calea glomerata relaxed the contractions induced by KCl (80 mM) and phenylephrine (10(-6) M) in a concentration-dependent manner (10(-6)-3x10(-4) g/ml), with IC(50) of 6.5x10(-5) (7.3-5.8) g/ml and 7.1x10(-5) (7.9-6.4) g/ml, respectively. Bioguided phytochemical fractionation of the ethanolic extract from C. schiedeanus was started. More than one active principle seems to be present, flavonoids and terpenoids compounds were detected.

Animals↗
PubMed2002

Screening of the topical anti-inflammatory activity of some Central American plants.

Hexane, chloroform and methanol extracts of seven herbal drugs used in the folk medicine of Central America against skin disorders (Aristolochia trilobata leaves and bark, Bursera simaruba bark, Hamelia patens leaves, Piper amalago leaves, and Syngonium podophyllum leaves and bark) were evaluated for their topical anti-inflammatory activity against the Croton oil-induced ear oedema in mice. Most of the extracts induced a dose-dependent oedema reduction. The chloroform extract of almost all the drugs exhibited interesting activities with ID(50) values ranging between 108 and 498 micro g/cm(2), comparable to that of indomethacin (93 micro g/cm(2)). Therefore, the tested plants are promising sources of principles with high anti-inflammatory activity.

Administration, Topical↗
PubMed1997

Anti-oedematous activities of the main triterpendiol esters of marigold (Calendula officinalis L.).

Separation and isolation of the genuine faradiol esters (1, 2) from flower heads of Marigold (Calendula (officinalis L., Asteraceae) could be achieved by means of repeated column chromatography (CC) and HPLC for the first time. Structure elucidation of faradiol-3-myristic acid ester 1, faradiol-3-palmitic acid ester 2 and psi-taraxasterol 3 has been also performed, without any previous degradation by means of MS, 1H-NMR, 13C-NMR and 2D-NMR experiments. The anti-oedematous activities of these three compounds were tested by means of inhibition of Croton oil-induced oedema of the mouse ear. Both faradiol esters showed nearly the same dose dependent anti-oedematous activity and no significant synergism appeared with their mixture. The free monol, psi-taraxasterol, had a slightly lower effect. Furthermore, faradiol was more active than its esters and than psi-taraxasterol and showed the same effect as an equimolar dose of indomethacin.

Animals↗
PubMed1998

Oral anti-inflammatory and anti-ulcerogenic activities of a hydroalcoholic extract and partitioned fractions of Turnera ulmifolia (Turneraceae).

Anti-inflammatory studies were conducted on rats or mice using a crude hydroalcoholic extract of the aerial parts of Turnera ulmifolia and it's partitioned fractions, i.e. the aqueous, ethyl acetate and ethanolic fractions. The hydroalcoholic extract and it's fractions (aqueous and ethanolic) inhibited carrageenan-induced edema. However, only the ethanolic fraction was used in the other experiments due to it's yield. The extract also inhibited the cotton pellet granuloma and the increase of vascular permeability induced by histamine, 5-hydroxytryptamine and prostaglandin E2, but not that produced by bradykinin. The extract or the fraction did not present analgesic activity in the writhing test using acetic acid and did not reduce croton oil-induced ear edema in mice. When the ethanolic fraction and LPS were administered i.p. to Balb/C mice 72 h before blood or peritoneal fluid collection, no changes were observed in the white or total blood cell counts in the peripheral blood. On the other hand, changes were observed in both total and differential cell counts in the peritoneal exudate since all doses of the fraction reduced the number of total leukocytes (mainly lymphocytes) obtained from the peritoneal exudate. In contrast to nonsteroidal anti-inflammatory drugs, the administration of the hydroalcoholic extract or the ethanolic fraction alone did not potentiate gastric mucosal lesions induced by aspirin. The extract and the fraction inhibited the appearance of gastric lesions induced by indomethacin, ethanol and pylorus ligature, but not those induced by stress. As also observed with carbenoxolone, the ethanolic fraction increased the wall mucus in hypothermical-restraint stress-induced gastric lesions. The anti-ulcerogenic effect of the extract and of the ethanolic fraction may be related to an increase of mucosal defensive factors, such as prostaglandin and mucus. The anti-inflammatory actions of the extract and the fraction may be due to an inhibitory effect on histamine and cyclooxygenase II, but not on cyclooxygenase I, because the extract and it's fraction present both anti-inflammatory and anti-ulcerogenic effects. The major substances present in the ethanolic fraction are flavonoids which will be isolated and identified.

Administration, Oral↗
PubMed1999

In vitro inhibition of drug-resistant and drug-sensitive strains of Mycobacterium tuberculosis by ethnobotanically selected South African plants.

Twenty South African medicinal plants used to treat pulmonary diseases were screened for activity against drug-resistant and drug-sensitive strains of Mycobacterium tuberculosis. A preliminary screening of acetone and water plant extracts against a drug-sensitive strain of Mycobacterium tuberculosis, H37Rv, was done by the agar plate method. Fourteen of the 20 acetone extracts showed inhibitory activity at a concentration of 0.5 mg/ml against this strain. Acetone as well as water extracts of Cryptocarya latifolia, Euclea natalensis, Helichrysum melanacme, Nidorella anomala and Thymus vulgaris inhibited the growth of M. tuberculosis. Given the activity of 14 acetone extracts at 0.5 mg/ml against the drug-sensitive strain by the agar plate method, a further study was done employing a rapid radiometric method to confirm the inhibitory activity. These active acetone extracts were screened against the H37Rv strain as well as a strain resistant to the drugs isoniazid and rifampin. The minimal inhibitory concentration of Croton pseudopulchellus, Ekebergia capensis, Euclea natalensis, Nidorella anomala and Polygala myrtifolia was 0.1 mg/ml against the H37Rv strain by the radiometric method. Extracts of Chenopodium ambrosioides, Ekebergia capensis, Euclea natalensis, Helichrysum melanacme, Nidorella anomala and Polygala myrtifolia were active against the resistant strain at 0.1 mg/ml. Eight plants showed activity against both strains at a concentration of 1.0 mg/ml.

Acetone↗
PubMed1999

Inhibition of chemical carcinogenesis by Psoralea corylifolia seeds.

Psoralea corylifolia L. (Fabaceae) seeds are extensively used in Ayurvedic medicine. Topical application of 100 mg/kg body weight of the active fraction (AF) of P. corylifolia seeds inhibited the growth and delayed the onset of papilloma formation in mice, initiated with 7,12-dimethyl benz(a) anthracene and promoted using croton oil. The AF at the same dose, when administered orally, inhibited the growth of subcutaneously injected 20-methylcholanthrene (MCA)--induced soft tissue fibrosarcomas significantly. The AF has been shown by gas chromatography analysis to be composed of a mixture of glycerides of fatty acids.

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

Traditional healers and the treatment of sexually transmitted illnesses in rural Zambia.

Lately there has been increasing interest regarding the practice of traditional healers and their use of indigenous plants to treat illnesses. Twenty-three local healers (n'ganga) in Chiawa, rural Zambia, were interviewed about knowledge, practices, and their use of indigenous plants in the diagnosis and treatment of sexually transmitted illnesses (STIs) among male clients. They were also asked about their perceptions of modern medicine. The study revealed that all the n'ganga diagnosed and treated three main types of STIs. They named them as: songeya, doroba and bola-bola. They treated the illnesses with Strychnos cocculoides; Musa species; Solanum delegoense; Ximenia caffra; Diplorynchus condylocarpon; and Croton megalobotrys. Ten of the n'ganga perceived modern medicine to be effective against STIs and five of them sometimes referred some of the clients to the local health centre. It is being argued that a scheme to incorporate the n'ganga into STD control activities in which they can be utilised to refer clients to modern medical facilities can be beneficial. Given the necessary health information and support, the n'ganga may effectively execute this scheme.

Adult↗
PubMed2000

Studies on the anti-inflammatory and related pharmacological properties of the aqueous extract of Bridelia ferruginea stem bark.

The anti-inflammatory profile of the aqueous extract of Bridelia ferruginea stem bark was investigated using both in vivo and in vitro models. The extract exhibited strong topical anti-inflammatory effect shown as inhibition of croton oil-induced ear oedema in mice, and reduced hind-paw swelling and growth retardation in the adjuvant-induced arthritis model in rats, following oral administration at 10, 20, 40 or 80 mg/kg. The extract (10-80 mg/kg, p.o.) caused an inhibition of increase in vascular permeability in both cyclophosphamide-induced haemorrhagic cystitis and acetic acid-induced vascular permeability in rats and mice, respectively. B. ferruginea produced stabilization of erythrocytes exposed to heat and stress-induced lysis. Antipyretic and analgesic properties of the extract were also observed.

Acetic Acid↗