Inhibition of NF-kappaB activation and iNOS induction by ent-kaurane diterpenoids in LPS-stimulated RAW264.7 murine macrophages.

Xerophilusin A (1), xerophilusin B (2), longikaurin B (3), and xerophilusin F (4) from Isodon xerophylus inhibit LPS-induced NO production in RAW 264.7 macrophages, with IC(50) values of 0.60, 0.23, 0.44, and 0.67 muM, respectively, and they all inhibited mRNA production in these same cells. They decreased the luciferase activity in RAW 264.7 cells transiently transfected with the NF-kappaB-dependent luciferase reporter, with IC(50) values of 1.8, 0.7, 1.2, and 1.6 muM, respectively. Compounds 1-3 reduced NF-kappaB activation, with compound 4 showing no effect, but p65 translocation from the cytoplasm to the nucleus and the LPS-induced degradation of IkappaB were inhibited by all four test compounds. These findings indicate that ent-kauranes are potential anti-inflammatory agents, with a specific mechanism in which both the inhibition of NF-kappaB translocation and the consequent decrease of pro-inflammatory mediators are implicated.

Anti-inflammatory activity of berenjenol and related compounds.

Berenjenol (1), isolated from Oxandra cf. xylopioides (Annonaceae), was tested on two different experimental models of inflammation. The compound showed anti-inflammatory activity in the test of acute mouse ear edema induced by TPA (54% inhibition, 1 micromol/ear) as well as in the test of subchronic inflammation induced by repeated application of TPA (57% inhibition, 7x1 micromol/ear). Moreover, while it reduced the expression of both COX-2 (65% inhibition at 50 microM) and iNOS (80% inhibition at 50 microM), it was not active against TNF-alpha and IL-1 beta in murine macrophages (RAW 264.7) stimulated with LPS. Structural modification of 1 gave two derivatives, berenjenol acetate (2) and 3-oxo-berenjenol (3). Of these, the latter had a high degree of activity in the acute test (66% inhibition, 1.1 micromol/ear), whereas the former showed no enhanced pharmacological properties. Interestingly, the original compound exhibited higher activity than either of its derivatives in the subchronic model. We thus concluded that whereas 3-oxidation of 1 (compound 3), but not 3-acetylation (2), increases the activity in the acute model of inflammation, structural modification of 1 does not enhance the compound's effects in the subchronic model.

Anti-inflammatory activity of flavonoids from Cayaponia tayuya roots.

ETHNOPHARMACOLOGICAL RELEVANCE: Taiuiá or tayuya (Cayaponia tayuya, Cucurbitaceae) is a climbing, lignified plant with a large swollen root that has traditionally been used as an anti-inflammatory and anti-rheumatic agent in the folk medicine of Brazil, Peru, and Colombia. THE AIM OF THE STUDY: We have assayed the pharmacological properties of a flavonoid fraction obtained from the butanol extract of Cayaponia tayuya roots using two models of topical mouse ear oedema, paying special attention to its influence on the induction on pro-inflammatory enzymes and peptidic mediators. MATERIAL AND METHODS: The in vivo experiments involved both the acute oedema induced by a single application of TPA and the subchronic inflammation brought on by repeated applications of TPA. The effects on the induction of pro-inflammatory enzymes and peptidic mediators in RAW 264.7 macrophages were analyzed with the aid of Western blot analysis. RESULTS: The extract was identified as a mixture of flavonoids in which vicenin-2, spinosin, isovitexin, and a mixture of swertisin and isoswertisin were found. In acute TPA-induced oedema in mouse ears, the flavonoid-enriched fraction (at a dose of 0.5mg/ear) inhibited the oedema by 66% (4.2+/-0.6 mg vs. 12.3+/-1.4 mg, P<0.01) while in the subchronic model, the inhibition reached 37% at a dose of 0.5mg/ear x 7 applications (7.5+/-0.6 mg vs. 11.9+/-1.3mg, P<0.05). When assayed in vitro, the flavonoid showed no toxicity at 33.45 microg/mL on RAW 264.7 macrophages. Although the nitric oxide production in these cells was moderately reduced (42%) at 33.45 microg/mL, the flavonoid-enriched fraction had no effect on TNF-alpha production. In addition, at 22.30 microg/mL, the test sample inhibited both iNOS and COX-2 expression by 98% and 49%, respectively. CONCLUSION: These results indicate that the anti-inflammatory activity of flavonoids from tayuya roots most likely stems from their inhibition of the induction of the enzymes COX-2 and iNOS.

Anti-inflammatory and apoptotic activities of pomolic acid isolated from Cecropia pachystachya.

The dichloromethane extract and pomolic acid ( 5) obtained from leaves of Cecropia pachystachya both reduced carrageenan-induced paw oedema in mice. Interestingly, while the triterpenoid inhibited the in vivo production of interleukin-1beta by 39 %, it had no effect on tumour necrosis factor-alpha production. We also demonstrated that both the dichloromethane extract and 5 inhibited the viability of human polymorphonuclear (PMN) cells in a time- and dose-dependent fashion. The PMN membrane integrity was determined with the aid of flow cytometry by means of the exclusion of propidium iodide as assay. Although the cell membrane integrity was altered, neither the extract nor 5 produced cellular necrosis. Moreover, the development of hypodiploid nuclei and DNA fragmentation in the PMN cells were both dependent on dose and time. Finally, in the annexin V-FITC binding assay, compound 5 increased the total of apoptotic cells by 42 % at 100 microM and by 71 % at 200 microM with respect to the control group. In conclusion, both the dichloromethane extract of ambay and isolated compound 5 inhibit the viability of PMN cells through apoptosis. Since they can regulate human neutrophil functions in this way, it is likely that these substances can also limit inflammation.

Virus y linfoma: leucemia / Virus and lymphoma: leukemia

El virus HTLV-I fue encontrado promotor de la Leucemia T del adulto y de la paraparesia espástica tropical. No es el único virus inculpado con la producción de neoplasias en el hombre. Se trata de un virus muy similar al HTLV-II o HIV, que se propaga en forma muy similar a éste. Tiene como diferencia fundamental, al producción de atipías linfoides y su muy largo período de incubación. Se lo encuentra en casi todo el mundo, pero su origen es el sur del Japón, si bien es endémico en la costa Americana del Pacífico, donde produce el cuadro neurológico mencionado anteriormente (AU)

Virus y linfoma: leucemia / Virus and lymphoma: leukemia

El virus HTLV-I fue encontrado promotor de la Leucemia T del adulto y de la paraparesia espástica tropical. No es el único virus inculpado con la producción de neoplasias en el hombre. Se trata de un virus muy similar al HTLV-II o HIV, que se propaga en forma muy similar a éste. Tiene como diferencia fundamental, al producción de atipías linfoides y su muy largo período de incubación. Se lo encuentra en casi todo el mundo, pero su origen es el sur del Japón, si bien es endémico en la costa Americana del Pacífico, donde produce el cuadro neurológico mencionado anteriormente