R. Della Loggia

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.

The Croton oil ear test revisited

Introduction Among the few tests available to detect the activity of topical antiinflammatory drugs, the Croton oil (CO) ear test is one of the most commonly used [1 3]. In this test the inflammatory response (IR) is usually quantified by measuring the increase in ear plug weight (EPW) at a single time-interval after CO application, when the IR is maximal. In this paper this experimental model of inflammation has been reevaluated in terms of time-course, contribution of granulocyte infiltration (GI) to the IR and response to both steroidal and non steroidal antiinflammatory drugs.

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.

Suitability of the MTT-based cytotoxicity assay to detect okadaic acid contamination of mussels

The suitability of a cytotoxicity assay based on the MTT colorimetric method has been evaluated for the detection of okadaic acid in mussels. On KB cells, okadaic acid exhibited a dose-dependent cytotoxic effect, the IC50 being inversely related to the exposure time (IC50 = 6.3 ng/ml, 4.0 ng/ml and 1.1 ng/ml after 24, 48 and 72 hr of contact, respectively). Using a contact time of 24 hr, the MTT cytotoxicity assay is suitable for revealing okadaic acid concentrations in mussel samples as low as 50 ng/g of digestive glands, with a sensitivity higher than that of the commercially available kits for enzyme-linked immunosorbent assay (ELISA). In the okadaic acid concentration range from 50 to 1500 ng/g of digestive glands the MTT cytotoxicity assay showed satisfactory accuracy and reproducibility. A high degree of correlation was found between the okadaic acid content of 16 naturally contaminated samples measured by the MTT cytotoxicity assay and by an ELISA.

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 (0ṁ5 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.

Screening of the topical anti-inflammatory activity of the bark of Acacia cornigera Willdenow, Byrsonima crassifolia Kunth, Sweetia panamensis Yakovlev and the leaves of Sphagneticola trilobata Hitchcock.

ETHNOPHARMACOLOGICAL RELEVANCE An investigation of topical anti-inflammatory activity was undertaken on plants used in Central America traditional medicine. AIM OF STUDY Four herbal drugs used in the folk medicine of Central America to treat inflammatory skin affections (Acacia cornigera bark, Byrsonima crassifolia bark, Sphagneticola trilobata leaves and Sweetia panamensis bark) were evaluated for their topical anti-inflammatory activity. MATERIALS AND METHODS Petroleum ether, chloroform and methanol extracts were obtained for herbal medicines and then extracts were tested on Croton oil-induced ear dermatitis model in mice. RESULTS Almost all the extracts reduced the Croton oil-induced ear dermatitis in mice and the chloroform ones showed the highest activity, with ID(50) (dose giving 50% oedema inhibition) values ranging from 112 microg/cm(2) (Byrsonima crassifolia) to 183 microg/cm(2) (Sphagneticola trilobata). As reference, ID(50) of the non-steroidal anti-inflammatory drug indomethacin was 93 microg/cm(2). CONCLUSIONS Lipophilic extracts from these species can be regarded as potential sources of anti-inflammatory principles.

An extract of Apium graveolens var. dulce leaves: structure of the major constituent, apiin, and its anti-inflammatory properties

Flavonoids, natural compounds widely distributed in the plant kingdom, are reported to affect the inflammatory process and to possess anti‐inflammatory as well as immunomodulatory activity in‐vitro and in‐vivo. Since nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) is one of the inflammatory mediators, the effects of the ethanol/water (1:1) extract of the leaves of Apium graveolens var. dulce (celery) on iNOS expression and NO production in the J774.A1 macrophage cell line stimulated for 24 h with Escherichia coli lipopolysaccharide (LPS) were evaluated. The extract of A. graveolens var. dulce contained apiin as the major constituent (1.12%, w/w, of the extract). The extract and apiin showed significant inhibitory activity on nitrite (NO) production in‐vitro (IC50 0.073 and 0.08 mg mL−1 for the extract and apiin, respectively) and iNOS expression (IC50 0.095 and 0.049 mg mL−1 for the extract and apiin, respectively) in LPS‐activated J774.A1 cells. The croton‐oil ear test on mice showed that the extract exerted anti‐inflammatory activity in‐vivo (ID50 730 μg cm−2), with a potency seven‐times lower than that of indometacin (ID50 93 μg cm−2), the non‐steroidal anti‐inflammatory drug used as reference. Our results clearly indicated the inhibitory activity of the extract and apiin in‐vitro on iNOS expression and nitrite production when added before LPS stimulation in the medium of J774.A1 cells. The anti‐inflammatory properties of the extract demonstrated in‐vivo might have been due to reduction of iNOS enzyme expression.

Anti-inflammatory activity of benzopyrones that are inhibitors of cyclo- and lipo-oxygenase.

The anti-inflammatory activity of three benzo-pyrones with prevalent lipooxigenase-inhibitory activity was studied using the Croton oil ear test in mice, in comparison with nordihydroguaieretic acid (NDGA) and indomethacin. Kaempferol, quercetin and NDGA possess a strong and prolonged anti-inflammatory effect, whereas the action of indomethacin appears relevant, but not long-lasting. In contrast the anti-inflammatory activity of esculetin is rather weak, but persistent.

Anti-inflammatory and peripheral analgesic activity of esculetin in vivo

Esculetin determined a reduction in oedema and granulocyte infiltration in the Croton oil ear test in vivo. The drug was able to inhibit Acethylcholine-writhing test and showed a LD50 of 1450 mg/kg i.p. and greater than 2000 mg/kg by mouth. In our experimental conditions, esculetin has an anti-inflammatory and analgesic effect.

Topical anti-inflammatory activity of Thymus willdenowii

The topical anti‐inflammatory activity of Thymus willdenowii Boiss (Labiatae) leaves, a herbal drug used in Moroccan folk medicine, has been studied using the croton oil ear test in mice. A bioassay‐oriented fractionation procedure showed that the activity concentrates in the chloroform extract, which has a potency similar to that of indometacin, the non‐steroidal anti‐inflammatory drug used as reference (ID50 (dose giving 50% oedema inhibition) = 83 μg cm−2 and 93 μg cm−2, respectively). The main compounds responsible for the anti‐inflammatory activity of T. willdenowii are ursolic acid and oleanolic acid. The flavonoids luteolin‐3′‐O‐glucuronide and eriodictyol‐7‐O‐glucoside were found for the first time in the genus Thymus.