Mouse Ear Edema Test Research Articles

Inhibition of phospholipase A2 activities and some inflammatory responses by the marine product ircinin.

The marine product ircinin has been tested for its effects on secretory and cytosolic phospholipase A2 (PLA2) activities in vitro as well as for inhibition of cellular functions in human neutrophils and inflammatory responses in mice. Ircinin inhibited Naja naja venom, human synovial recombinant, bee venom and zymosan-injected rat air pouch PLA2 with IC50 values in the microM range, similar to those of the known inhibitor scalaradial. On the other hand, ircinin was less active on cytosolic PLA2 from human monocytes and decreased potently the release of LTB4 in human neutrophils. This marine product affected weakly human neutrophil functions like superoxide generation and degranulation. In the zymosan-injected rat air pouch ircinin inhibited in vivo the activity of PLA2 present in exudates and reduced dose-dependently myeloperoxidase levels, whereas cell migration was inhibited only at the highest dose tested. This compound exerted a potent anti-oedematous effect after topical application in the mouse ear oedema test. Ircinin is a new inhibitor of PLA2 activity and our results suggest a potential role for this marine product as an inhibitor of inflammatory processes.

Anti-inflammatory action of Pluchea sagittalis: involvement of an antioxidant mechanism.

Pluchea sagittalis, (Lam.) Cabr., a popular medicinal herb grown in South America, was studied for anti-inflammatory and antioxidant activities. The anti-edema action of P. sagittalis aqueous extract was assayed in different models of inflammation: 1) the mouse ear edema test induced by arachidonic acid and croton oil; 2) the rat hind-paw edema test produced by several inflammatory inductors: carrageenan, dextran, zymosan, platelet-activating factor (PAF) and arachidonic acid; 3) a subacute model based on the rat carrageenan air-pouch granuloma test. Blood leukocyte free radical production was measured by flow cytometry with 2',7'-dichlorofluorescin diacetate (DCFH-DA) in vivo, in rats with induced air-pouch granuloma, and in a model in vitro. stimulating leukocytes with hydrogen peroxide. The aqueous extract of P. sagittalis showed a marked anti-inflammatory effect in both ear edema tests, dextran and carrageenan hind-paw edemas and carrageenan air-pouch model. It also had a potent antioxidant activity in blood leukocytes, both in vivo and in vitro. Our results correlate the reduction of free radical production with the anti-inflammatory effect of this plant.

The antiinflammatory effect of some species from South America

Extracts (aqueous, methanol and dichloromethane) from Ambrosia tenuifolia, Aristolochia triangularis, Baccharis tucumanensis, Campyloneuron phyllitidis and Eupatorium christieanum were screened for antiinflammatory activity. On the croton oil induced mouse ear oedema test, the highest activities were exhibited by dichloromethane extracts assayed, especially those of Baccharis tucumanensis and Campyloneuron phyllitidis. On the carrageenan mouse paw oedema test, Baccharis tucumanensis and Campyloneuron phyllitidis showed the highest activity.

Antiinflammatory activity of isoflavonoids fromPueraria radix and biochanin A derivatives

For comparing with flavones/flavonols, isoflavonoids isolated fromPueraria radix and chemically synthesized from biochanin A were evaluated for the antiinflammatory activity using mouse ear edema test. Isoflavonoids such as daidzein and puerarin showed the significant antiinflammatory activity at a dose of 2 mg/mouse, although their activity was generally less than that of flavones/flavonols. 7-O-Substitution of biochanin A was not favorable for the antiinflammatory activity.

Effect of liposomes on percutaneous penetration of lipophilic materials

Liposomes were prepared of two lipophilic drugs, dl-α-tocopherol nicotinate (TN) and the anti-inflammatory substance, L440. In the case of dl-α-tocopherol nicotinate liposomes, oleoyl-hydrolyzed animal protein (OHAP) was added in order to control the vesicle size. The skin penetration ability of both drugs from liposomal gels into human stratum corneum was determined in vivo by a stripping method and compared with conventional galenical formulations. The anti-inflammatory effect of the released L440 was examined in the ear edema model in mice. The penetration tests showed significantly higher absorption rates for both drugs after application of the liposomal preparations in comparison to other topical formulations. However, only a slight dependence of the extent of drug permeation into the stratum corneum on liposome diameter was observed. The pharmacological effect of L440 was investigated in the mouse ear edema test (Young et al., J. Invest. Dermatol., 80 (1982) 48–52; and J. Invest. Dermatol., 82 (1984) 367–371). No difference was found between the liposome preparation and an o/w base, whereas a w/o base yielded only a 50% reduction in edema.