Salvador Máñez

An Update Review of Saffron and its Active Constituents

This paper reviews the literature on recent research on the chemical composition and pharmacological activities of saffron (Crocus sativus) and its active constituents, mainly as antitumoral, hypolipidemic and tissue oxygenation enhancement agents.

Assessment of the anti-inflammatory activity and free radical scavenger activity of tiliroside.

Three flavonoids, gnaphaliin, pinocembrin and tiliroside, isolated from Helichrysum italicum, were studied in vitro for their antioxidant and/or scavenger properties and in vivo in different models of inflammation. In vitro tests included lipid peroxidation in rat liver microsomes, superoxide radical generation in the xanthine/xanthine oxidase system and the reduction of the stable radical 1,1-diphenyl-2-pycryl-hydrazyl (DPPH). Acute inflammation was induced by application of 12-O-tetradecanoylphorbol 13-acetate (TPA) to the mouse ear or by subcutaneous injection of phospholipase A(2) or serotonin in the mouse paw. Eczema provoked on the mouse ear by repeated administration of TPA was selected as a model of chronic inflammation. The flavonoids were assayed against sheep red blood cell-induced mouse paw oedema as a model of delayed-type hypersensitivity reaction. The most active compound, both in vitro and in vivo, was tiliroside. It significantly inhibited enzymatic and non-enzymatic lipid peroxidation (IC(50)=12.6 and 28 microM, respectively). It had scavenger properties (IC(50)=21.3 microM) and very potent antioxidant activity in the DPPH test (IC(50)=6 microM). In vivo, tiliroside significantly inhibited the mouse paw oedema induced by phospholipase A(2)(ED(50)=35.6 mg/kg) and the mouse ear inflammation induced by TPA (ED(50)=357 microg/ear). Pinocembrin was the only flavonoid that exhibited anti-inflammatory activity in the sheep red blood cell-induced delayed-type hypersensitivity reaction. However, only tiliroside significantly reduced the oedema and leukocyte infiltration induced by TPA. As in the case of other flavonoids, the anti-inflammatory activity of tiliroside could be based on its antioxidant properties, although other mechanisms are probably involved.

Oleanonic acid, a 3-oxotriterpene from Pistacia, inhibits leukotriene synthesis and has anti-inflammatory activity

One of the best known bioactive triterpenoids is oleanolic acid, a widespread 3-hydroxy-17-carboxy oleanane-type compound. In order to determine whether further oxidation of carbon 3 affects anti-inflammatory activity in mice, different tests were carried out on oleanolic acid and its 3-oxo-analogue oleanonic acid, which was obtained from Pistacia terebinthus galls. The last one showed activity on the ear oedema induced by 12-deoxyphorbol-13-phenylacetate (DPP), the dermatitis induced by multiple applications of 12-O-tetradecanoyl-13-acetate (TPA) and the paw oedemas induced by bradykinin and phospholipase A2. The production of leukotriene B4 from rat peritoneal leukocytes was reduced by oleanonic acid with an IC50 of 17 microM. Negligible differences were observed in the response of both triterpenes to DPP, bradykinin, and phospholipase A2, while oleanonic acid was more active on the dermatitis by TPA and on the in vitro leukotriene formation. In conclusion, the presence of a ketone at C-3 implies an increase in the inhibitory effects on models related to 5-lipoxygenase activity and on associated in vivo inflammatory processes.

Anti‐inflammatory and antioxidant properties of Helichrysum italicum

The anti‐inflammatory and antioxidant activities of the aerial part of Helichrysum italicum extracts have been established in various in‐vivo and in‐vitro experimental models. The results obtained on the acute oedemas induced by 12‐O‐tetradecanoylphorbol 13‐acetate (TPA) and ethyl phenylpropiolate in the mouse ear, by serotonin and phospholipase A2 (PLA2) in the mouse paw, on chronic inflammation induced by repeated application of TPA in the mouse ear and on the delayed‐type hypersensitivity induced by sheep red blood cells suggest that said anti‐inflammatory activity is due to the effects of compounds expressed via a corticoid‐like mechanism. In addition, the antioxidant activity of the extracts seems to be implicated in this anti‐inflammatory activity, as the former inhibits enzymatic and non‐enzymatic lipid peroxidation and has free‐radical scavenger properties. We conclude that the anti‐inflammatory activity of Helichrysum italicum can be explained by multiple effects, including inflammatory enzyme inhibition, free‐radical scavenging activity and corticoid‐like effects.

Effect of selected triterpenoids on chronic dermal inflammation

The activity of four natural triterpenoids on a 12-O-tetradecanoylphorbol-13-acetate multiple-dose model of skin chronic inflammation was studied. Erythrodiol and ursolic acid were significantly effective. The most important features concerning structure-activity relationship and previous data on the effect of these triterpenoids on other inflammatory conditions are discussed.

Topical anti-inflammatory activity of some Asian medicinal plants used in dermatological disorders.

The topical anti-inflammatory activity of extracts from Cassia angustifolia, Rheum palmatum, Coptis chinensis, Phellodendron amurense and Scutellaria baicalensis, plants used in traditional East Asian medicine against different skin disorders, was studied. Though in different degree, all the extracts significantly inhibited the edema induced by 12-O-tetradecanoylphorbol-13-acetate (TPA), in both single or multiple application, oxazolone, and arachidonic acid (AA). None of the extracts inhibited in vitro the activity of phospholipase A(2) (PLA(2)) from Naja naja.

Influence of traditional Chinese anti-inflammatory medicinal plants on leukocyte and platelet functions.

The enzymes 5‐lipoxygenase and elastase are therapeutic targets in dermatological disorders such as psoriasis. Fifteen extracts from traditional Chinese medicinal plants used to treat topical inflammations were screened for their inhibitory effect on lipoxygenase, cyclooxygenase and elastase activity in intact leukocytes and platelets. Astragalus membranaceus, Forsythia suspensa and Poria cocos inhibited 5‐lipoxygenase, with IC50 values of 141, 80 and 141 μg mL−1, respectively. The latter two species, along with Angelica dahurica and Angelica pubescens, also inhibited elastase (IC50 values of 80, 123, 68 and 93 μg mL−1, respectively), while A. pubescens, Atractylodes macrocephala, Lentinus edodes, Rehmannia glutinosa and Paeonia lactiflora selectively inhibited 12‐(S)‐HHTrE production, a valid marker of cyclooxygenase activity. The inhibition of phospholipase A2 activity by P. cocos is discussed. Dehydrotumulosic and pachymic acids, which have been isolated from P. cocos, were shown to inhibit leukotriene B4 release. The results indicate that both P. cocos and F. suspensa are potentially valuable species in the management of skin pathologies involving chronic inflammation.

Anti-inflammatory effects of south american Tanacetum vulgare

In recent years the role of phenolic compounds and sesquiterpene lactones, particularly parthenolide, in the anti‐migraine and anti‐inflammatory effects of Tanacetum parthenium (Asteraceae) has attracted much attention. However, the closely‐related cosmopolitan species T. vulgare has remained outside the mainstream of research in this field.

On the anti-inflammatory and anti-phospholipase A2 activity of extracts from lanostane-rich species.

We have studied extracts from three species rich in lanostane triterpenes for their activity against different in vivo models of inflammation induced by TPA, EPP and PLA(2). The inhibitory effect against PLA(2) in vitro was also studied. When the Poria cocos extract was tested against PLA(2)-induced mouse paw edema, it was active by the oral and parenteral routes. Its effect was greater in both magnitude and duration than that of Pistacia terebinthus and Ganoderma lucidum extracts. P. terebinthus was effective against chronic and acute inflammation, and according to a preliminary chromatographic analysis, its seems to be a good source of lanostane anti-inflammatory agents. G. lucidum was the least effective of the three species studied and, unlike the other two, failed to inhibit the activity of PLA(2) in vitro.

In vivo activity of pseudoguaianolide sesquiterpene lactones in acute and chronic inflammation.

The pseudoguaianolide sesquiterpene lactones 4-alpha-O-acetyl-pseudoguaian-6beta-olide (1), hymenin (2), ambrosanolide (3), tetraneurin A (4), parthenin (5), hysterin (6) and confertdiolide (7) were evaluated for their ability to affect the inflammation responses induced by different agents. All the compounds showed activity against the 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced mouse ear edema. The ethyl phenylpropiolate (EPP)-induced mouse ear edema was inhibited by compounds 3, 5 and 7. However, when sesquiterpene-lactones were assayed on the arachidonic acid (AA)-induced mouse ear edema, none of them were active. The only sesquiterpene lactone orally active against the paw mouse edema induced by carrageenan was 7, which gave a 46% edema inhibition after 3 h. On the other hand, compounds 3, 5 and 7 reduced the serotonin-induced paw edema in mice, although compound 7 was inactive in presence of cycloheximide. In addition, the sesquiterpene lactones were assayed against the chronic inflammation induced by repeated application of TPA on mouse ear. Confertdiolide was the most active compound; it reduced the edema by 87% and had a more moderate effect against the leukocyte recruitment (36% reduction in myeloperoxidase (MPO) levels). A histological study of ear the samples treated with 7 presented no detectable morphological lesions such as those treated with dexamethasone. On the oxazolone-induced delayed type hypersensitivity (DTH) only compounds 4 and 5 were active 24 h after the challenge. Compound 5 affected polymorphonuclear leukocyte infiltration (69% reduction in MPO levels). The results suggest that the especial chemical structure and spatial conformation of confertdiolide may facilitate its anti-inflammatory effect.