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PubMed1985

Evidence from two classic irritation tests for an anti-inflammatory action of a natural extract, Echinacina B.

The roots of Echinacea angustifolia (fam. Compositae) were used to obtain an antiphlogistic, immunostimulating and skin repairing extract. On the basis of these potential actions, the extract is used in cosmetic preparations. The aim of this study was to evaluate the anti-inflammatory activity of the extract using different irritation tests. The irritation reaction was induced by application of 0.015 ml of 0.25% croton oil in water to the ears of mice. The raw extract (Echinacina B), topically applied, inhibited oedema both at the maximum (6 hr) and in the decreasing phase (18 hr), and this effect was directly proportional to the doses used. Echinacina B was found to be more potent than the positive control, benzidamine, a topical non-steroidal anti-inflammatory drug. In addition, the extract given iv 1 hr before injection of 0.05 ml of 1% carrageenan into the hind paws of rats inhibited oedema in the histaminic and in the later phases of the phlogistic process. These data show the qualitative value of irritation tests for studying the anti-inflammatory action of a natural plant extract.

Animals↗
PubMed1982

Carcinogenicity of some pyrrolic pyrrolizidine alkaloid metabolites and analogues.

Repeated topical doses of dehydromonocrotaline, a putative primary toxic metabolite of the pyrrolizidine alkaloid monocrotaline, followed by repeated treatments with croton oil, produced malignant tumours of the skin in LACA mice. A chemically similar alkylating agent, 2,3-bistrimethylace-toxymethyl-1-methylpyrrole, was carcinogenic without use of a promoter, confirming a preliminary report. Its high activity was due to the intact ester, not to its hydrolysis products. Dehydroretronecine (DHR), a less reactive secondary metabolite of monocrotaline, was also carcinogenic to LACA mouse skin, but it was less active than previously reported in experiments with another strain. Similar carcinogenicity was shown by the synthetic 2,3-bishydroxymethyl-1-methylpyrrole, but not by 2,3-bis-hydroxymethyl-5-methyl-1-phenylpyrrole, which has a high level of antimitotic activity.

Alkaloids↗
PubMed1983

Single dose carcinogenicity of procarbazine in rats.

Rats carrying a 2-day-old subcutaneous air pouch were treated with single doses of procarbazine. Local fibrosarcomas developed in the pouch after oral, intraperitoneal and local administration of 300 mg/kg, but no tumours were induced if the drug was injected into unstimulated subcutaneous tissue. Tumours only appeared in those animals in which growth of the granuloma tissue was stimulated with a dose of croton oil. The high dose of procarbazine (300 mg/kg) also induced an increase in total tumour incidence at other sites.

Adenoma↗
PubMed1991

Inhibitory effects of Ixora javanica extract on skin chemical carcinogenesis in mice and its antitumour activity.

Topical application of 100 mg/kg body weight of Ixora javanica flower extract inhibited the growth and delayed the onset of papilloma formation in mice initiated with 7,12-dimethylbenz[a]anthracene (DMBA) and promoted using croton oil. The extract at the same dose, when administered orally inhibited the growth of subcutaneously injected 20-methylcholanthrene (MCA)-induced soft tissue fibrosarcomas significantly. Oral administration of 200 mg/kg of the extract inhibited the growth of intraperitoneally transplanted sarcoma-180 and Ehrlich ascites carcinoma tumours besides showing an increase in the life span of the treated mice. Toxicity studies showed that the blood urea nitrogen levels were elevated post treatment. The active compounds responsible for the above inhibitory effects on tumour growth were identified as ferulic acid (4-hydroxy-3-methoxy cinnamic acid) and its regionmer 3-hydroxy-4-methoxy cinnamic acid.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1992

Promotion pattern and tumour types in two-stage rat skin carcinogenesis.

Carcinogenic studies were performed on the skin of inbred male Lister rats using 7,12-dimethylbenz[alpha]anthracene (DMBA) in low doses (2.5 mg and 5.0 mg), followed by promotion with croton oil (CO) in one half of the animals. The clinically observed tumour rate did not differ after the two carcinogen doses and was practically unaffected by promotion, only a marginal increase in effect being noted after DMBA 2.5 mg. Also the latency periods were alike. The total tumour crop was increased by promotion, but histologically the predominant clinical skin tumour was a sebaceous proliferation with or without associated papillomatous squamous cell hyperplasia. This lesion did not in microscopic structure or cellular characteristics fulfil the criteria of a neoplastic tumour. Basal cell carcinomas, adnexal tumours and pure squamous cell tumours were rare and were not promoted by CO. CO had a marked promotion effect, but only on the mixed sebaceous-papillomatous hyperplasias, which were more than doubled in number. In conclusion, carcinogenesis was weak after the low DMBA-doses, and promotion by CO of neoplastic tumours was not seen.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1992

Promoting action of cashew nut shell oil in DMBA-initiated mouse skin tumour model system.

The commercially available oil derived from the shell of cashew nut (Anacardium occidentale) was tested for its potency in promoting the DMBA-initiated cells into papillomas in a murine two-stage skin tumorigenesis model system. Male Swiss albino mice (9-10-weeks-old) were assorted into different groups and treated topically with single sub-carcinogenic doses of DMBA (50 micrograms in 0.1 ml acetone) followed by application of 1% and 2% shell oil in acetone three times a week. Animals were sacrificed after 20 weeks from the commencement of the experiment. The results imply a weak tumour promoting effect of cashew nut shell oil as the mean tumour incidences were found to be 1.1 and 2.5 in 1% and 2% oil treatment groups, respectively, while the corresponding figure vas 6.6 in the positive control group (DMBA and 1% croton oil in acetone). Few speculative mechanisms for the observed effect of cashew nut shell oil on initiated skin are discussed.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1993

Effect of asoka on the intracellular glutathione levels and skin tumour promotion in mice.

The bark of Saraka asoca (asoka) is commonly used to treat various diseases by the Indian system of medicine and in Sri Lanka. Further purification and chemical analysis of the active compound from the bark extract of asoka showed that (-)-epicatechin was responsible for the observed antitumour/anticarcinogenic activity. Papilloma formation in mice initiated with 7,12-dimethylbenz[a]anthracene (DMBA) and promoted using croton oil was inhibited by the topical application of 100 mg/kg body weight (b.w.) of (-)-epicatechin isolated from asoka bark extract. Oral administration of the same dose restricted the growth of s.c. injected 20 methylcholanthrene (MCA) induced soil tissue fibrosarcomas significantly in mice. Elevations of almost 2-4-fold in the intracellular reduced glutathione and related enzymes viz., glutathione reductase and glutathione S-transferase of sarcoma-180 tumour cells were noted in the presence of 1 microgram/ml of (-)-epicatechin, further highlighting its antiproliferative effect.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1996

Effect of free fatty acids on two-stage skin carcinogenesis in mice.

The effect of n-3 and n-6 free fatty acids on two stage skin carcinogenesis in mice was studied. Stearic, linoleic, arachidonic, and eicosapentaenoic acids inhibited both initiation and promotion stages of skin carcinogenesis. Although no direct correlation between lipid peroxidation and papilloma formation was observed, a trend towards an increase in the formation of lipid peroxides with the inhibitory effect of fatty acids on papilloma development was noted. In general, the fatty acids applied were incorporated mainly into the phospholipid and free fatty acid pools. All the fatty acids tested, except eicosapentaenoic and docosahexaenoic acids, inhibited the binding of benzo[a]pyrene (BP) to DNA. On the other hand, BP and croton oil-induced skin cell proliferation was not influenced by any of the fatty acids used. In conclusion, the results of the present study suggest that inhibition of papilloma formation by free fatty acids is complex and can be attributed to a limited extent only to their ability to inhibit BP binding to DNA, to block cell proliferation and enhance the lipid peroxidation process.

Animals↗
PubMed1995

Anti-inflammatory activities of flavonoids of Baphia nitida Lodd. (Leguminosae) on mice and rats.

Leaves of Baphia nitida are used in folk medicine for the treatment of inflamed and infected umbilical cords in Nigeria. Phytochemical analysis of the leaves detected tannins, flavonoids and saponin glycosides. Flavonoid rich fraction of the leaf, obtained by a chromatographic process, was formulated into an ointment and tested at 3 dose levels for anti-inflammatory activity against croton oil and heat induced inflammation on ears of mice and depilated backs of rats, respectively. Both provide evidence for the ability of this fraction to inhibit the inflammatory condition on the rodents. The activity was found to be dose related, and the mouse ear model was found to be the more sensitive of the two tests used. Hydrocortisyl cream used as a positive control reference was significantly active in both systems. These results provide a scientific basis for the traditional use of the leaves of Baphia nitida as an anti-inflammatory agent.

Animals↗
PubMed1991

Interleukin-1 beta: a possible mediator of lung inflammation and airway hyperreactivity.

Interleukin-1 (IL-1), a peptide released from monocytes/macrophages, plays an important role in the inflammatory and immune responses. Airway hyperreactivity and the underlying airway inflammation are common features in asthma pathology. We investigated and characterized the inflammatory alterations induced within the guinea-pig respiratory system by IL-1 beta. Injection of IL-1 beta (1-6 micrograms/animal) into the pleural space resulted in a dose-dependent inflammatory response, as shown by the formation of pleural exudate and leucocyte recruitment. A threshold dose of IL-1 beta (1 micrograms/animal) markedly potentiated the inflammatory reaction triggered by the classical proinflammatory agent croton oil, underlining the amplifying role of IL-1 beta in the inflammatory events. The inflammatory process induced by intrapleural injection of IL-1 beta (6 micrograms/animal) was associated with the development of a hyperreactive phenomenon which involved both the peripheral and large airways. In fact, increased contractile activity of histamine was evident in the tracheas and parenchymal strips isolated from guinea-pigs exposed to IL-1 beta. These results provide evidence for a possible role of IL-1 beta in the genesis of airway inflammation and bronchial hyperreactivity.

Animals↗
PubMed2005

Selective in vivo anti-inflammatory action of the galactolipid monogalactosyldiacylglycerol.

The thermophilic blue-green alga ETS-05 colonises the therapeutic thermal muds of Abano and Montegrotto, Italy. Following the isolation, purification and identification of monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), sulphoquinovosyldiacylglycerol (SQDG) and phosphatidylglycerol from ETS-05, we here examine their in vivo anti-inflammatory activities. MGDG, DGDG and SQDG inhibit croton-oil-induced ear oedema in the mouse in a dose-dependent manner. Inhibition by MGDG is greater than that of the reference drug, betamethasone 17,21-dipropionate, and is largely abrogated following acyl group saturation. SQDG is the least potent of these glycoglycerolipids, and shows an early transient effect. In the in vivo carrageenan-induced paw oedema model in the mouse, the inhibitory effects are again dose dependent, with an enhanced efficacy of MGDG over DGDG, SQDG and the reference drug, indomethacin. These compounds are all less toxic than indomethacin. The selective and enhanced inhibitory effects of MGDG over DGDG indicate the mechanisms behind these in vivo anti-inflammatory actions.

Animals↗
PubMed2005

Gaultherin, a natural salicylate derivative from Gaultheria yunnanensis: towards a better non-steroidal anti-inflammatory drug.

One of the major factors limiting the use of non-steroidal anti-inflammatory drugs is gastrointestinal toxicity. Gaultherin, 2-[(6-O-beta-D-Xylopyranosyl-beta-D-glucopyranosyl)oxy] benzoic acid methyl ester, a natural salicylate derivative extracted from Gaultheria yunnanensis, has been shown to have analgesic and anti-inflammatory effects and lack gastric ulcerogenic effect compared to aspirin in our primary study. The aim of this study was to investigate the mechanism of action of gaultherin, which may rely on its active metabolite, and the mechanism responsible for the non-ulcerogenic property. The results showed that gaultherin (200 mg/kg) significantly inhibited the abdominal contractions in the acetic acid-induced writhing test in mice. The anti-inflammatory effect of gaultherin was demonstrated in the croton oil-induced ear edema model in mice. The results showed that gaultherin and equimolar dose of aspirin produced comparable inhibitory effects. The study of the metabolism characters of gaultherin in mice and rats indicated that gaultherin could be metabolically converted to salicylate, which produced the pharmacological effects, and provided effective concentrations for an extended period. In vitro metabolism experiment showed that gaultherin was metabolized by beta-glycosidase produced by human intestinal bacteria and esterases in intestine, blood and liver successively to release salicylate finally. The study suggested gaultherin did not cause gastric ulcer for the reason that it released salicylate in intestine slowly, not in stomach and it left the cyclooxygenase-1 unaffected, which was the source of cytoprotective prostaglandins in gastric epithelium.

Abdominal Pain↗
PubMed2004

Anti-steroidogenic activity of the two Indian medicinal plants in mice.

The chloroform extract of Croton roxburghii bark (CECR, Euphorbiaceae) and ethyl acetate extract of Zizyphus jujuba bark (EAZJ, Rhamnaceae) were evaluated for anti-steroidogenic activity in the adult female mouse. This study was designed to assess the effects of CECR and EAZJ on ovarian steroidogenisis. Antifertility activity was evaluated by observing the estrus cycle, body weight, wet weight of ovaries, steroidogenic enzymes, and substrates. Blood profiles were estimated to find out the toxic manifestations of the extracts. CECR and EAZJ each arrested the normal estrus cycle of adult female mouse at diestrus stage and reduced the wet weight of ovaries significantly. Cholesterol and ascorbic acid content in ovaries of crude extract-treated mice were significantly elevated. The significant inhibition of delta(5)-3beta-hydroxysteroid dehydrogenase (delta(5)-3beta-HSD) and glucose-6-phosphate dehydrogenase (G-6-PDH), the two key enzymes involved in ovarian steroidogenisis, were also observed in mouse after 18 days of treatment. Hematological profiles, biochemical estimations of whole blood and serum remains unaltered in extract-treated mouse. Normal estrus cycle and ovarian steroidogenisis were restored after withdrawal of treatment with CECR and EAZJ on average 27 and 32 days, respectively. Antifertility activities of crude extracts were found to be reversible.

3-Hydroxysteroid Dehydrogenases↗
PubMed2006

Anti-inflammatory and anti-nociceptive activities of Pluchea quitoc (DC.) ethanolic extract.

Pluchea quitoc DC. (Asteraceae), a plant widely distributed throughout Brazil and popularly known as "quitoco", "madre-cravo" or "tabacarana", is used in traditional medicine for the treatment of inflammation, as well as of digestive and respiratory diseases. The anti-inflammatory and anti-nociceptive activities of the ethanolic extract (EE) from aerial parts of this plant were evaluated in mice and rats. Oral treatment with the EE (1-2g/kg, p.o.) decreased the paw oedema induced by carrageenan in rats, showed anti-nociceptive effects on the tail-flick test and on acid-induced writhing in mice, and inhibited both phases of pain (neurogenic and inflammatory) of the formalin test in rats. Topical application (EE 1.25, 2.5 and 5.0mg) inhibited the ear oedema induced by croton oil in mice. The results support the folkloric use of the plant in inflammatory processes.

Acetic Acid↗
PubMed2004

Effect of Onosma echioides on DMBA/croton oil mediated carcinogenic response, hyperproliferation and oxidative damage in murine skin.

The current study unveils the effect of O. echioides extract on two-stage skin carcinogenesis and on tumor promoter induced markers and oxidative stress in Swiss mice. Treatment of dorsal shaven cutaneous portions of the mice with single topical application of benzoyl peroxide (BPO) followed by exposure to ultraviolet B (UVB) radiation induced significant oxidative stress and elevated the marker parameters of tumor promotion. Similar effects were observed with 12-O-tetradecanoyl phorbol-13-acetate (TPA) treatment. Pretreatment of O. echioides extract (5 mg & 10 mg/Kg b.wt) in both the studies with BPO+UVB and TPA restored the levels of reduced glutathione (GSH) and cellular protective enzymes (p < 0.05). Concomitantly, malondialdehyde (MDA) formation and hydrogen peroxide (H2O2) content were also reduced significantly (p < 0.05) at both the doses. The promotion parameters tested (ornithine decarboxylase activity and DNA synthesis) were also significantly suppressed (p < 0.05). Thereafter, we proceeded with studies on mouse skin carcinogenesis. After ten days of 7,12-dimethylbenz(a)anthracene (DMBA) treatment, twice-weekly applications of croton oil for 20 weeks resulted in 100% incidence of tumors in the animals. However, O. echioides showed reduction in the number of tumors/ mouse and percentage of tumor bearing mice at the end of the study. The study was further histologically confirmed. The protective activity of the plant might be due to the two major constituents (alkannins and shikonins) present in the plant. O. echioides is thus, proposed to be helpful in prevention of experimental skin carcinogenesis.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed2005

Effects of methyl-eugenol administration on behavioral models related to depression and anxiety, in rats.

Croton zehntneri (Cz) is a popular plant in Brazilian folk medicine. Recently, the use of its essential oil showed depressive activity response in the central nervous system (CNS). Chemical studies show that the main compound of this oil is the methyl-eugenol (ME). This work seeks to evaluate the ME activity in behavioral models of depression and anxiety, in the rat. Male rats (60 days old) were divided into four groups (n = 10) and treated with doses of 1.0, 3.0 and 10.0 ml/100 g body wt., v.o., of ME (experimental) and saline (control). One hour after treatment, they were observed in the forced swimming test and 15 min later in the open-field test. A decrease was observed in the immobility time during the forced swimming test for all experimental groups, in comparison with control group (C = 168.8 +/- 27.3; 1.0 microl = 139.1 +/- 23.5; 3.0 microl = 137.2 +/- 18.7 and 10.0 microl = 139.8 +/- 23.6). The open-field results showed no differences in comparison to the control group. The same was observed for social interaction, plus-maze and holeboard tests, suggesting no alterations in anxiety behavior. These data suggest that ME administration induced antidepressive CNS alterations, expressed by the smallest immobility in the swimming model, and not of a level able to alter motor and exploratory activity in the open-field. The absence of effects observed in the open-field can be a result of the experimental contingency, taking low anxiety levels. These data are in contradiction to observations with Cz essential oil in these models.

Animals↗
PubMed2005

Extracts and constituents of Lavandula multifida with topical anti-inflammatory activity.

The topical anti-inflammatory activity of the ethanol and aqueous extracts from the aerial parts of Lavandula multifida L. (Lamiaceae), used in the Moroccan traditional medicine, was investigated by inhibition of the Croton oil-induced ear edema in mice. The biological assay revealed a dose-dependent anti-inflammatory activity for the ethanol extract, while the aqueous one was less active. Bioassay-guided fractionation of the ethanol extract led to identify four triterpenic acids of oleanane series, four pimarane and one iso-pimarane diterpenes, as well as the phenolic monoterpene carvacrol and its glucoside. Some of these compounds revealed an anti-inflammatory activity comparable to that of indomethacin.

Administration, Cutaneous↗
PubMed2005

Activity of taraxasteryl acetate on inflammation and heat shock protein synthesis.

Pluchea sagittalis whole plant dichloromethane extract showed inhibitory activity in several inflammatory models: rat hind paw-edema, mice ear edema, and air-pouch rat granuloma. The extract inhibited the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in stimulated human neutrophils. It also showed inhibitory effect on heat shock protein 72 (hsp72) synthesis in stimulated neutrophils, while it had opposite effects on unstimulated cells. The triterpene taraxasteryl acetate was obtained from the dichloromethane extract by bioassay directed isolation, being active against induced ROS and RNS production in human neutrophils. In mice ear edema (induced by phorbol-12-mirystate-13-acetate, croton oil and arachidonic acid), taraxasteryl acetate showed a topical anti-inflammatory activity similar to the extract, but at 1/20 of the dose. The same ratio was observed for the inhibition of hsp72 production in stimulated human neutrophils. In unstimulated monocytes and neutrophils, taraxasteryl acetate showed a higher stimulating activity of hsp72 production than the extract, involving different mechanisms in each cell type. To our knowledge, taraxasteryl acetate is the first natural product for which a dual effect on the hsp response is reported.

Animals↗