Fernando Alzate

Pentacyclic triterpenes from Cecropia telenitida with immunomodulatory activity on dendritic cells

Pentacyclic triterpene Natural product Cytokine modulation Anti-inflammatory activity Dendritic cells Pentacyclic triterpenes are a large family of plant metabolites that exhibit a wide array of biological activities. The genus Cecropia,which encompasses many plant species, has been used as traditional medicine for the treatment of inflammatory diseases and is known to produce many active pentacyclic triterpenes. In this study we investigated the chemical composition of a pentacyclic triterpene fraction from the roots of Cecropia telenitidaCuatrec., Urticaceae. A novel compound, which we termed yarumic acid, and four known molecules (serjanic acid, spergulagenic acid A, 20-hydroxy-ursolic acid and goreishic acid I) were isolated and characterised. In a dendritic cell (DC)based assay, we demonstrated that non-toxic doses of these pentacyclic triterpenes inhibited the secretion of at least one of the proinflammatory cytokines tested (IL-1β, IL-12p40, IL-12p70, TNF-α). Spergulagenic acid A also inhibited nitric oxide production in lipopolysaccharide-stimulated dendritic cell. Serjanic acid and spergulagenic acid A, which were the most potent abundant compounds in the pentacyclic triterpene fraction, showed the most activity in the dendritic cell-based assay. These results show that all pentacyclic triterpenes might contribute to the anti-inflammatory activities of C. telenitida. Moreover, yarumic acid as well as the four known pentacyclic triterpenes, can be exploited as potential immunomodulatory/anti-inflammatory agents.

Antileishmanial Effect of 5,3′-Hydroxy-7,4′-dimethoxyflavanone of Picramnia gracilis Tul. (Picramniaceae) Fruit: In Vitro and In Vivo Studies

Species of Picramnia genus are used in folk medicine to treat or prevent skin disorders, but only few species have been studied for biological activity and chemical composition. P. gracilis Tul. is a native species from Central and South America and although its fruits are edible, phytochemical analysis or medicinal uses of this species are not known. In the search of candidates to antileishmanial drugs, this work aimed to evaluate the antileishmanial activity of P. gracilis Tul. in in vitro and in vivo studies. Only ethanolic extract of fruits showed leishmanicidal activity. The majoritarian metabolite was 5,3′-hydroxy-7,4′-dimethoxyflavanone ether that exhibited high activity against L. (V.) panamensis (EC50 17.0 + 2.8 mg/mL, 53.7 μM) and low toxicity on mammalian U-937 cells, with an index of selectivity >11.8. In vivo studies showed that the flavanone administered in solution (2 mg/kg/day) or cream (2%) induces clinical improvement and no toxicity in hamsters with CL. In conclusion, this is the first report about isolation of 5,3′-hydroxy-7,4′-dimethoxyflavanone of P. gracilis Tul. The leishmanicidal activity attributed to this flavanone is also reported for the first time. Finally, the in vitro and in vivo leishmanicidal activity reported here for 5,3′-hydroxy-7,4′-dimethoxyflavanone offers a greater prospect towards antileishmanial drug discovery and development.

EL CARIOTIPO DE BOMAREA PATINII BAKER SUBSP. PATINII (ALSTROEMERIACEAE)

The karyotype oi Bomarea patinii Baker subsp. patinii from Colombia was examined. The species has a karyotype 2n = 2x= 18, with a haploid formula 2m + lsm+ 5st+ lt-sat. The reported karyotype is asymmetric (Asl %= 75.51). The most of the chromosomes are acrocentric. This results are compared with other species oiBomarea from South America.

Leishmanicidal and cytotoxic activity of extracts and saponins from Ilex laurina (Aquifoliaceae)

Purpose: To evaluate the leishmanicidal and cytotoxic activity of alcohol and non-alcohol extracts and saponins from Ilex laurina . Methods: Extracts were obtained by percolation with solvents of different polarities: hexane, dichloromethane, ethyl acetate and ethanol. The ethyl acetate extract was subjected to silica gel column chromatography eluting with a step gradient of dichloromethane-methanol. All products were evaluated in vitro for leishmanicidal activity against amastigotes of leishmania panamensis and cytotoxicity on U-937 cells. Results: Two saponins were isolated from the ethyl acetate extract. The ethyl acetate extract showed high leishmanicidal activity against intracellular amastigotes of L. panamensis (EC 50 , 7.5 ± 1.5 μg/mL) and low activity against axenic amastigotes (EC 50 , 52.8 ±1.6 μg/mL); this extract showed also high cytotoxicity (LC 50 , 57.7 ± 12.1 μg/mL). Saponin 2 exhibited high activity against intracellular amastigotes (EC 50 , 5.9 ± 0.5 μg/mL) but also showed high cytotoxicity on U-937 cells (EC 50 , 25.7 ± 6.1 μg/mL). This compound showed similar leishmanicidal activity and cytotoxicity to meglumine antimoniate and amphotericin B, respectively, drugs currently used for the treatment of leishmaniasis. Conclusions: Based on these results, Ilex laurina is a potential source of compounds that can lead to the development of new therapeutic alternatives against leishmaniasis. Keywords: Leishmaniasis, Antiprotozoal, Saponin, Ilex laurina , Aquifoliaceae

Resección de fibroelastoma papilar mitral mediante cirugía mínimamente invasiva en paciente con accidente cerebrovascular

Paciente quien consulto con sintomas neurologicos y se realizo diagnostico de accidente cerebrovascular embolico cuya etiologia consistio en un tumor cardiaco de la valvula mitral (fi broelastoma) con confi rmacion histologica. Fue intervenido quirurgicamente mediante tecnica minimamente invasiva a traves del torax, con excelente evolucion, sin infeccion ni requerimientos sanguineos; no presento secuelas valvulares ni neurologicas. Se reporto reincorporacion temprana a la vida laboral.

Antiprotozoal Activity of Ethanol Extracts of Some Bomarea Species

Abstract The antiprotozoal activity of 26 ethanol extracts derived from 13 species of the genus Bomarea (Alstroemeriaceae) were evaluated against the promastigote forms of three Leishmania species (L. amazonensis L., L. braziliensis Vianna, and L. donovani Laveran & Mesnil) and the epimastigote form of Trypanosoma cruzi Chagas. IC50 values for leishmanicidal activities were between 4.9 and 98.6 μ g/mL, B. setacea extracts being the most active against the three species of Leishmania. Amphotericin B (IC50 = 0.2 μ g/mL) and pentamidine (IC50 = 10 μ g/mL) were used as control in this assay. IC50 values for antitrypanosomal activities were between 65.2 and 92.7 μ g/mL, whereas the control benznidazole had an IC50 value of 2 μ g/mL.