Cytotoxic effects of Euterpe oleraceae fruit oil (açaí) in rat liver and thyroid tissues

Abstract Euterpe oleracea Mart., Arecaceae, fruit (açaí) presents considerable potential for the development of new medicines due to its phytochemical composition and antioxidant activity. More recently, special attention has been given to the pharmacological potential of the fruit's oil. This study analysed the histological and histochemical effects of different dosages of açaí oil on rat's liver and thyroid cells, in order to evaluate its cytotoxic potential after administration for consecutive days. Male Wistar rats were treated with the açaí oil by gavage at doses of 30, 100 and 300 mg/kg, for 14 days, within a 24 h interval. Liver and thyroid fragments were collected for histology (hematoxylin and eosin) and histochemistry analysis (blue of Nilo (lipids), Baker (lipids), bromophenol blue (protein), PAS (polysaccharides)). The results showed that animals exposed to açaí oil presented alterations in the liver cells, where the integrity of the liver tissue was increasingly lost as the açaí oil doses increased. Nuclear pyknosis was observed in several hepatocytes, evidencing the occurrence of cell death. Alteration in the amount of lipids, polysaccharides, vacuoles in the cytoplasm, and proliferation of Kupffer cells were observed in histochemical analyzes. As for the thyroid of the treated rats, alterations were observed in the size of the follicular lumen and also in the connective tissue found between the follicles. Under the experimental conditions employed in the present study, the cytotoxicity observed in this work is worrying, specially considering the liver, when frequent or continuous damage could lead pathological disorders in this organ.

Effect of Artemisia annua L. leaves essential oil and ethanol extract on behavioral assays / Efeito do extrato etanólico bruto e óleo essencial das folhas de Artemisia annua em modelos comportamentais

Artemisia annua has been used as a traditional plant for the treatment of malaria and fever in China because of the presence of its active compound, artemisinin. The present study evaluated the central activity of the essential oil and the crude ethanol extract of A. annua L. in animals as a part of a psychopharmacological screening of this plant. The extract was prepared in ethanol (AEE) and the essential oil (AEO) obtained by hydrodistillation, both with fresh leaves. Induced immobility, the forced swimming test (FST) and the open-field test (OFT) are well-known animal models to study drug-induced depression. The administration of A. annua essential oil or crude ethanol extract increased the immobility time in the FST and decreased other activities (ambulation, exploration, rearing and grooming) in the OFT in animals. Both AEO and AEE prolonged pentobarbital-induced sleep as well, but the essential oil had a marked effect. Observing these results, it is possible to suggest that A. annua crude ethanol extract and essential oil could act as depressors on the Central Nervous System (CNS).

Artemisia annua tem sido utilizada tradicionalmente para o tratamento de malária e febre na China devido à presença do princípio ativo, artemisinina. O presente trabalho avaliou a atividade central de do óleo essencial obtido por hidrodestilação e do extrato etanólico bruto de folhas frescas de A. annua em modelo in vivo como parte de um screening farmacológico dessa espécie. Sono induzido por pentobarbital, nado forçado e o ensaio de campo aberto são modelos de estudo conhecidos para o estudo de fármacos sobre depressão induzida. A administração do óleo essencial ou extrato bruto etanólico de A. annua aumentaram o tempo de imobilidade no teste do nado forçado. Por outro lado, diminuíram outros parâmetros no campo aberto, como ambulação, exploração, o ato de lamber as patas ou se lamber. Ambos produtos aumentaram o tempo de sono induzido por pentobarbital, com o óleo essencial apresentando um efeito superior ao do extrato. Pela análise dos resultados, é possível sugerir que tanto o extrato bem como o óleo essencial podem atuar como depressores do Sistema Nervoso Central (SNC).

Evaluation of the in vivo mutagenic potential of hydroalcoholic extracts of the northern highbush blueberry (Vaccinium corymbosum L. Ericales, Ericaceae) on peripheral blood cells of Swiss mice (Mus musculus Rodentia, Muridae)

The northern highbush blueberry (Vaccinium corymbosum L. Ericales, Ericaceae) is very rich in anthocyanins, natural pigments which have strong antioxidant properties and potential health benefits, resulting in the worldwide use the blueberry as a medicinal plant. We investigated the mutagenic potential of simple hydroalcoholic extracts of V. corymbosum acutely administrated by gavage to Swiss mice at doses of 1 g kg-1, 1.5 g kg-1 and 2 g kg-1. Peripheral blood cells were collected 4 h and 24 h post-gavage and assessed by the alkaline comet assay, with further blood samples being collected at 48 h and 72 h for assessment using the micronucleus (MN) assay. Our results show that the V. corymbosum extracts did not induce any statistically significant increase in the average amount of DNA damage in peripheral blood leukocytes. However, we did record a significant increase in the frequency of micronucleated polychromatic erythrocytes at the three doses tested.

Clastogenicity of Piper cubeba (Piperaceae) seed extract in an in vivo mammalian cell system

The plant Piper cubeba is widely distributed in tropical and subtropical regions and is used medically for various purposes but has not yet been evaluated for genotoxicity. We used male and female Swiss mice and Wistar rats and the comet assay and micronucleus test to investigate the mutagenic potential of a crude extract of P. cubeba seeds. The rodents were administered 0.5 g kg-1, 1.0 g kg-1 and 1.5 g kg-1 of the extract by gavage. For the Swiss mice, peripheral blood was collected 24 h after treatment for the comet assay, and at 48 and 72 h for the micronucleus test. For the Wistar rats, peripheral blood and hepatic cells were collected for the comet assay and bone marrow cells were collected for the micronucleus test 24 h after treatment. At 1.5 g kg-1, the highest dose tested, the extract induced a statistically significant increase in both the mean number of micronucleated polychromatic erythrocytes and the level of DNA damage in the rodent cell types analyzed. Under our experimental conditions, the P. cubeba seed extract was genotoxic in vivo when administered orally to mice and rats.

Cytogenetic divergence between two sympatric species of Characidium (Teleostei, Characiformes, Crenuchidae) from the Machado River, Minas Gerais, Brazil

Cytogenetic studies were performed on two sympatric species of Characidium, C. gomesi and C. cf. zebra, from the Grande River basin, Minas Gerais State, Brazil. Although both species had a chromosome number of 50 with a karyotype exclusively consisting of meta- and submetacentric chromosomes, interspecific diversity was detected concerning the size of the two first chromosome pairs of the karyotypes. Active nucleolus organizer regions (NORs) were located at the terminal position on the long arm of the 17th pair of C. gomesi and at subterminal position on the long arm of the 23rd pair of C. cf. zebra. For both species the fluorochrome CMA3 stained only the NOR-bearing pair of chromosomes. The heterochromatin pattern also showed some differentiation between these species restricted to the centromeric or pericentromeric region of C. cf. zebra and practically absent in C. gomesi. These data are discussed concerning chromosome diversification in this fish group.

No clastogenic activity of Caesalpinia ferrea Mart. (Leguminosae) extract on bone marrow cells of Wistar rats

Extracts of the fruits of Caesalpinia ferrea Mart. (Leguminosae) are widely consumed in folkloric medicine in Brazil and several other countries without any genetic toxicity evaluation. In this study we investigated, the clastogenic and cytotoxic potential of the crude aqueous extract of the fruits of C. ferrea in Wistar rat bone marrow cells using the micronucleus and chromosomal aberration test systems. The animals were treated by gavage with 3 concentrations of the extract, 500, 1000 and 1500 mg/kg, and cyclophosphamide 30 mg/kg. Bone marrow cells were collected 24 h after the treatment. There was no statistically significant difference in the mean of micronucleated polychromatic erythrocytes (MNPCE), mean number of chromosomal aberrations or mitotic index (MI) for the 3 concentrations compared with negative control suggesting that the crude aqueous extract from the fruits of the C. ferrea has no clastogenic and cytotoxic effect in Wistar rat bone marrow cells.

In vivo evaluation of the mutagenic potential and phytochemical characterization of oleoresin from Copaifera duckei Dwyer

We characterized the chemical constituents of Copaifera duckei oleoresin and used dermal application to Wistar rats to evaluated its possible mutagenic and cytotoxic activities on peripheral blood reticulocytes and bone marrow cells. Chemical characterization of the oleoresin revealed the presence of sesquiterpene hydrocarbons, an unidentified neutral diterpene and diterpene acids. To evaluate mutagenicity evaluation the rats were treated with 10, 25 and 50% of the LD50 dose of the oleoresin for three consecutive days and peripheral blood collected after 0, 24, 48 and 72 h for micronucleus analysis. The rats were humanly sacrificed 24 hours after the last treatment and chromosome preparations made using standard techniques. At the three concentrations and the three time intervals tested we found that there were no statistically significant differences in either the mean number of micronucleated reticulocytes (MNRETs) or the number of chromosomal aberrations as to the negative control. However, at 25 and 50% of the LD50 dose of the oleoresin there was a significant decrease in the mitotic index (MI) as compared to the negative control. Under our experimental conditions, C. duckei V11 oleoresin produced no mutagenic effects on bone marrow cells or in peripheral reticulocytes as assessed by chromosome aberrations and the micronucleus test respectively, but showed cytotoxic activity at high doses

Evaluation of the genotoxic potential of the Hypericum brasiliense (Guttiferae) extract in mammalian cell system in vivo

Plants of the genus Hypericum, long used in folk medicine, contain active compounds which present, anti-septic, diuretic, digestive, expectorant, vermifugal, anti-depressive and other properties. The possible clastogenic effect of a H. brasiliense extract was tested in vivo on the bone marrow cells of Wistar rats. The extract was administered by gavage at doses of 50, 150 and 300 mg/kg body weight. Experimental and control animals were submitted to euthanasia 24 h after the treatment for micronucleus (MN) and chromosome preparations. H. brasiliense extract did not induce statistically significant increases in the average numbers of MN or chromosome aberrations in the test systems employed.

R- and G-band patterns in Astyanax scabripinnis paranae (Pisces, Characiformes, Characidae)

The absence of longitudinal bands in fish chromosomes has been associated with technical problems in chromosome preparations or the absence of a structural compartmentalization in the fish genome. In the present study, a R-banding pattern was obtained using a replication banding technique by in vivo treatment with 5-bromodeoxyuridine (5-BrdU). G-banding patterns were obtained after trypsin treatment and also after chromosome cleavage by in situ treatment with the restriction endonuclease BamHI. A similar G-banding pattern was also obtained after cleavage with the endonuclease HinfI. Presence of a resolute R- and G-banding patterns shows that Astyanax scabripinnis paranae chromosomes could present an isochore-like structure similar to that found in other vertebrates.