Leishmaniasis is a "neglected tropical disease" and serious public health issue in Brazil. While dogs are recognized as particularly important reservoirs, recent reports of domestic cats infected with Leishmania sp. in urban areas suggest their participation in the epidemiological chain of the parasite in endemic areas. The aim of this study was to screen domestic cats for Leishmania sp. infection in an area where human and canine visceral leishmaniasis are endemic, followed by the identification of the species circulating in cats. We collected peripheral blood, lymph-node aspirates and bone marrow from 100 adult animals, both male and female, and analyzed the samples using cytological and molecular (PCR) detection techniques. We detected Leishmania in 6% of animals, which were then analyzed by RFLP-PCR to identify the species. Leishmania infantum (synonym: L. chagasi), a species responsible for visceral leishmaniasis in humans and other animals, was identified from all six samples. Amastigotes were observed in the peripheral blood, bone marrow and lymph-node aspirates in 4 of the 6 PCR-positive animals. The presence of infected cats in endemic areas should not be neglected, because it demonstrates the potential role of these animals in the biological cycle of the pathogen.

This study is the first phytochemical investigation of Selaginella sellowii and demonstrates the antileishmanial activity of the hydroethanolic extract from this plant (SSHE), as well as of the biflavonoids amentoflavone and robustaflavone, isolated from this species. The effects of these substances were evaluated on intracellular amastigotes of Leishmania (Leishmania) amazonensis, an aetiological agent of American cutaneous leishmaniasis. SSHE was highly active against intracellular amastigotes [the half maximum inhibitory concentration (IC50) = 20.2 µg/mL]. Fractionation of the extract led to the isolation of the two bioflavonoids with the highest activity: amentoflavone, which was about 200 times more active (IC50 = 0.1 μg/mL) and less cytotoxic than SSHE (IC50 = 2.2 and 3 μg/mL, respectively on NIH/3T3 and J774.A1 cells), with a high selectivity index (SI) (22 and 30), robustaflavone, which was also active against L. amazonensis (IC50 = 2.8 µg/mL), but more cytotoxic, with IC50 = 25.5 µg/mL (SI = 9.1) on NIH/3T3 cells and IC50 = 3.1 µg/mL (SI = 1.1) on J774.A1 cells. The production of nitric oxide (NO) was lower in cells treated with amentoflavone (suggesting that NO does not contribute to the leishmanicidal mechanism in this case), while NO release was higher after treatment with robustaflavone. S. sellowii may be a potential source of biflavonoids that could provide promising compounds for the treatment of cutaneous leishmaniasis.

Da madeira e das cascas do caule de Terminalia fagifolia foram isolados dois 1,3-diarilpropanos, 1-(4'-hidróxi-2'-metóxifenil)-3-(3"-metóxi-4"-hidróxifenil)-propano e 1-(2'-hidróxi-4',6'dimetóxifenil)-3-(3"-metóxi-4"-hidróxifenil)-propano, sete flavanonas, naringenina, 5-hidróxi-4',7dimetóxiflavanona, sakuranetina, isosakuranetina, 7,4'-dimetóxiflavanona, 7-hidróxi-4'metóxiflavanona, 7-metóxi-4'-hidróxiflavanona, duas chalconas, 2',4'-diidroxi-4-metóxichalcona e 2'-4-diidroxi-4'-metóxichalcona, uma flavana, 7,4'-diidróxi-3'-metóxiflavana e nove triterpenos pentacíclicos, ácido arjúnico, arjunetina, arjungenina, arjunglucosídeo I, ácido arjunólico, arjunglucosídeo II, 23-galoilarjunglucosídeo (isolado como seus derivados mono-, die trimetilados após metilação com diazometano), ácido betulínico e acetato do ácido ursólico, além de ácido gálico e sitosterol. Os diarilpropanos representam os primeiros membros desta classe em Combretaceae e as flavanonas e chalconas estão sendo descritas pela primeira vez na família. As substâncias isoladas foram avaliadas quanto às atividades citotóxica in vitro (células Hep 2 e H 292 , carcinomas de laringe e mucoepidermóide de pulmão humanos, respectivamente) e antioxidante. As chalconas, o diarilpropano 1-(2'-hidróxi-4',6'-dimetóxifenil)-3-(3"-metóxi-4"-hidróxifenil)propano e os derivados die tri-metilados de 23-galoilarjunglucosídeo foram os mais ativos quanto à atividade citotóxica. Two 1,3-diarylpropanes, 1-(4'-hydroxy-2'-methoxyphenyl)-3-(3"-methoxy-4"hydroxyphenyl)-propane and 1-(2'-hydroxy-4',6'-dimethoxyphenyl)-3-(3"-methoxy-4"hydroxyphenyl)-propane, seven flavanones, naringenin, naringenin-4',7-dimethyl-ether, sakuranetin, isosakuranetin, liquiritigenin-4',7-dimethyl-ether, liquiritigenin-7-methyl-ether and liquiritigenin-4'-methyl-ether, two chalcones, isoliquiritigenin-4-methyl-ether and isoliquiritigenin-4'-methyl-ether, one flavan, 7,4'-dihydroxy-3'-methoxyflavan, nine triterpenes, arjunic acid, arjunetin, arjungenin, arjunglucoside I, arjunolic acid, arjunglucoside II, 23galloylarjunglucoside II (isolated as its mono-, di-and triO methyl derivatives after methylation with diazomethane), betulinic acid and ursolic acid acetate, along with gallic acid and sitosterol were isolated from the heartwood and trunk bark of of Terminalia fagifolia. The flavanones and chalcones obtained in the present work are new in the Combretaceae and this is the first report of the occurrence of 1,3-diarylpropanes in this family. The isolated compounds were evaluated for their in vitro cytotoxic activity against two human cancer cell lines (Hep 2 larynx carcinoma and H 292 lung mucoepidermoid carcinoma) and antioxidant properties. Isoliquiritigenin-4-methylether, isoliquiritigenin-4'-methyl-ether, 1-(2'-hydroxy-4',6'-dimethoxyphenyl)-3-(3"-methoxy-4"-hydroxyphenyl)-propane and the di-and triO methyl derivatives of 23-galloylarjunglucoside II were the most active in the cytotoxic assay.

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The bioactive ethyl acetate phase obtained from the latex of Croton urucurana Baillon afforded a novel orbitide (1), [1-9-NαC]-crourorb A1, that proved active against NCI-ADR/RES (ovary, multidrug-resistance phenotype) cells with the same potency as doxorubicin (positive control) and inactive up to the highest concentration tested against nontumor NIH/3T3 cells. The structure elucidation was based on 1D and 2D NMR spectroscopy, further supported by HRESIMS data and by application of Marfey's method for determination of the absolute configuration of its amino acid residues. This is the first orbitide obtained from C. urucurana.