Effects of artichoke (Cynara scolymus) leaf and bloom head extracts on chemically induced DNA lesions in Drosophila melanogaster.

The genotoxicity of bloom head (BHE) and leaf (LE) extracts from artichoke (Cynara scolymus L.), and their ability to modulate the mutagenicity and recombinogenicity of two alkylating agents (ethyl methanesulfonate - EMS and mitomycin C - MMC) and the intercalating agent bleomycin (BLM), were examined using the somatic mutation and recombination test (SMART) in Drosophila melanogaster. Neither the mutagenicity nor the recombinogenicity of BLM or MMC was modified by co- or post-treatment with BHE or LE. In contrast, co-treatment with BHE significantly enhanced the EMS-induced genotoxicity involving mutagenic and/or recombinant events. Co-treatment with LE did not alter the genotoxicity of EMS whereas post-treatment with the highest dose of LE significantly increased this genotoxicity. This enhancement included a synergistic increase restricted to somatic recombination. These results show that artichoke extracts promote homologous recombination in proliferative cells of D. melanogaster.

Evaluation of the mutagenicity and genotoxicity of Arrabidaea chica Verlot (Bignoneaceae), an Amazon plant with medicinal properties.

Arrabidaea chica Verlot (Bignoniaceae) is an important folk medicine plant native to the Amazon region and used to treat anemia, hemorrhage, inflammation, intestinal colic, hepatitis, and skin affections. Although studies showed its therapeutic properties, little knowledge regarding genotoxic properties of this plant is available. The aim of this study was to determine the potential mutagenic and genotoxic/antigenotoxic effects of an A. chica chloroformic fraction (Ac-CF) obtained from leaves containing bioactive metabolites. The mutagenic effects were evaluated using the Salmonella mutagenicity assay, with TA98, TA97a, TA100, TA102, and TA1535 strains, with and without metabolic activation. In vivo mutagenic and genotoxic/antigenotoxic effects were investigated using the micronucleus (MN) test in bone marrow and alkaline comet assay in blood and liver after administration of 100, 500, or 1000 mg/kg Ac-CF in CF-1 mice by gavage (once a day for 3 d). In vitro antioxidant potential was evaluated using DPPH and xanthine/hypoxanthine assays. Ac-CF was not mutagenic in any of the Salmonella typhimurium strains tested and showed negative responses for mutagenicity and genotoxicity in mice. Further, Ac-CF displayed antigenotoxic effects by decreasing the oxidative DNA damage induced by hydrogen peroxide by greater than 50% in blood and liver. The antioxidant action detected in the in vitro assays demonstrated IC50 of 0.838 mg/ml in the xanthine/hypoxanthine assay and IC50 of 28.17 µg/ml in the DPPH assay. In conclusion, Ac-CF did not induce mutagenic and genotoxic effects and was able to protect DNA against oxidative damage in vivo, suggesting that this fraction may not pose genetic risks, although further toxicology assays are necessary.

Homologous recombination induced by doxazosin mesylate and saw palmetto in the Drosophila wing-spot test.

Benign prostatic hyperplasia (BPH) is the most common tumor in men over 40 years of age. Acute urinary retention (AUR) is regarded as the most serious hazard of untreated BPH. α-Blockers, such as doxazosin mesylate, and 5-α reductase inhibitors, such as finasteride, are frequently used because they decrease both AUR and the need for BPH-related surgery. An extract of the fruit from American saw palmetto plant has also been used as an alternative treatment for BPH. The paucity of information available concerning the genotoxic action of these compounds led us to assess their activity as inducers of different types of DNA lesions using the somatic mutation and recombination test in Drosophila melanogaster. Finasteride did not induce gene mutation, chromosomal mutation or mitotic recombination, which means it was nongenotoxic in our experimental conditions. On the other hand, doxazosin mesylate and saw palmetto induced significant increases in spot frequencies in trans-heterozygous flies. In order to establish the actual role played by mitotic recombination and by mutation in the genotoxicity observed, the balancer-heterozygous flies were also analyzed, showing no increment in the total spot frequencies in relation to the negative control, for both drugs. Doxazosin mesylate and saw palmetto were classified as specific inducers of homologous recombination in Drosophila proliferative cells, an event linked to the loss of heterozygosity.

Genotoxic and antigenotoxic activity of acerola (Malpighia glabra L.) extract in relation to the geographic origin.

Malpighia glabra L, popularly known as acerola, is considered a functional fruit and therefore is taken to prevent disease or as adjuvant to treatment strategies, since the fruit is an undeniable source of vitamin C, carotenoids, and flavonoids. Acerola is a natural source of vitamin C, flavonoids, and carotenoids. Its chemical composition is affected by genetic uniformity of the orchards and environmental factors. Considering the extensive growth of the culture of acerola in Brazil as well as its widespread use, this study evaluates the genotoxic and antigenotoxic activity of acerola in relation to geographical origin using the comet assay in mice blood cells in vitro. No acerola samples showed potential to induce DNA damage, independently of origin. Also, for antigenotoxicity activity, only the acerola sample from São Paulo reduced DNA damage induced by hydrogen peroxide (by about 56%). The sample from Ceará showed good antioxidant activity by the 2,2-diphenyl-1-picrylhydrazyl assay, in agreement with its higher rutin, quercetin, and vitamin C levels. Additional studies with other treatment regimens are necessary to better understand the impact of the complex mixture of acerola on genomic stability.

Treatment with aqueous extract from Croton cajucara Benth reduces hepatic oxidative stress in streptozotocin-diabetic rats.

Croton cajucara Benth is a plant found in Amazonia, Brazil and the bark and leaf infusion of this plant have been popularly used to treat diabetes and hepatic disorders. The present study was designed to evaluate the oxidative stress as well as the therapeutic effect of Croton cajucara Benth (1.5 mL of the C. cajucara extract i.g.) in rats with streptozotocin-induced diabetes. Croton cajucara Benth was tested as an aqueous extract for its phytochemical composition, and its antioxidant activity in vitro was also evaluated. Lipid peroxidation and superoxide dismutase, catalase, and glutathione reductase activities were measured in the hepatic tissue, as well as the presence activation of p65 (NF-κB), through western blot. Phytochemical screening of Croton cajucara Benth detected the presence of flavonoids, coumarins and alkaloids. The extract exhibited a significant antioxidant activity in the DPPH-scavenging and the hypoxanthine/xanthine oxidase assays. Liver lipid peroxidation increased in diabetic animals followed by a reduction in the Croton-cajucara-Benth-treated group. There was activation of p65 nuclear expression in the diabetic animals, which was attenuated in the animals receiving the Croton cajucara Benth aqueous extract. The liver tissue in diabetic rats showed oxidative alterations related to the streptozotocin treatment. In conclusion the Croton cajucara Benth aqueus extract treatment effectively reduced the oxidative stress and contributed to tissue recovery.

Antigenotoxicity and antioxidant activity of Acerola fruit (Malpighia glabra L.) at two stages of ripeness.

Genotoxic and antigenotoxic effects of acerola fruit at two stages of ripeness were investigated using mice blood cells. The results show that no ripeness stage of acerola extracts presented any genotoxic potential to damage DNA (Comet assay) or cytotoxicity (MTT assay). When antigenotoxic activity was analyzed, unripe fruit presented higher DNA protection than ripe fruit (red color) extract. The antioxidant capacity of substances also showed that unripe samples inhibit the free radical DPPH more significantly than the ripe ones. The results about determination of compounds made using HPLC showed that unripe acerola presents higher levels of vitamin C as compared to ripe acerola. Thus, vitamin C and the complex mixture of nutrients of Malpighia glabra L., and especially its ripeness stages, influenced the interaction of the fruit extract with the DNA. Acerola is usually consumed when ripe (red fruit), although it is the green fruit (unripe) that has higher potential as beneficial to DNA, protecting it against oxidative stress.

Pharmacological evaluation of Copaifera multijuga oil in rats.

CONTEXT: Copaiba oil is an oleoresin made up of resin acids and volatile compounds, and it is obtained by tapping the trunks of trees that are members of the Copaifera L. (Leguminoseae) genus and are found in tropical parts of Latin America. OBJECTIVE: This study analyzed the chemical composition of Copaifera multijuga Hayne oil and conducted preclinical trials to investigate anti-inflammatory effects and any action it may have on the central nervous system (CNS) of rats. MATERIALS AND METHODS: The chemical analysis was carried out using gas chromatography with mass spectroscopy. Anti-inflammatory activity was measured by leucocytes mobilization, by chemotaxis assay in Boyden's chamber, and by pleurisy model in rats. CNS effect was determined by plus maze and open-field assays. The statistical test applied was analysis of variance (ANOVA) followed by Tukey's test or ANOVA followed by Duncan's test. RESULTS: The oil was composed of sesquiterpenes with the predominance of ß-caryophyllene (36.0%), followed by α-copaene (18.8%), ß-bisabolene (8.5%), and α-trans-bergamotene (7.0%). Data demonstrated that at 100 and 200 mg/kg doses and at a concentration of 200 µl/ml copaiba essential oil presented anti-inflammatory effects both in vivo and in vitro based on reduced leukocyte migration to the rats' pleural cavity and to the chemotactic agent lipopolysaccharide solution, respectively. During the experiments investigating CNS effects, locomotive and exploratory activities were reduced and the animals' anxiety increased at 100 and 200 mg/kg. CONCLUSION: The results obtained suggest that copaiba oil has an interesting anti-inflammatory effect and important effect on the CNS.

Effect of Agaricus blazei Murill on the pulmonary tissue of animals with streptozotocin-induced diabetes.

The present study was designed to evaluate the oxidative stress as well as the therapeutic effect of Agaricus blazei Muril (A. Blazei) in rats with streptozotocin-induced diabetes. We used 25 Wistar rats, and DM was induced by injecting streptozotocin (70 mg/Kg i.p.). Agaricus blazei Muril was administered daily starting 40 days after disease onset. A. Blazei was tested as an aqueous extract for its phytochemical composition, and its antioxidant activity in vitro was also evaluated. Lipoperoxidation (LPO), and superoxide dismutase (SOD), catalase, and glutathione peroxidase activities were measured in the pulmonary tissue, as well as the presence of inducible nitric oxide synthase (iNOS), through immunohistochemistry. An anatomopathologic study was also performed. Phytochemical screening of A. Blazei detected the presence of alkaloids and saponins. The extract exhibited a significant antioxidant activity in the DPPH-scavenging and the hipoxanthine/xanthine oxidase assays. Pulmonary LPO increased in diabetic animals (0.43 +/- 0.09; P < .001) as compared to the control group (0.18 +/- 0.02), followed by a reduction in the A. Blazei-treated group (0.33 +/- 0.04; P < .05). iNOS was found increased in the lung in diabetic rats and reduced in the A. Blazei-treated group. The pulmonary tissue in diabetic rats showed oxidative alterations related to the streptozotocin treatment. The A. Blazei treatment effectively reduced the oxidative stress and contributed to tissue recovery.

Influência dos processos de secagem sobre o teor de flavonoides e na atividade antioxidante dos extratos de Baccharis articulata (Lam.) Pers., Asteraceae / The Influence of drying processes on flavonoid level and the antioxidant activity of Baccharis articulata (Lam.) extracts

O objetivo deste trabalho foi verificar o teor de quercetina obtido dos extratos de partes aéreas de Baccharis articulata (Lam.) Pers., Asteraceae, submetidas a diferentes técnicas de secagem, bem como a avaliação de sua atividade antioxidante in vitro. Foi verificada maior concentração deste flavonoide nas amostras secas em estufa, porém não houve diferença significativa na atividade farmacológica das amostras analisadas.

The objective of this work was to verify the influence of different drying processes on the levels of quercetin of the aerial parts of Baccharis articulata (Lam.) Pers., Asteraceae, as well as the evaluation of the in vitro antioxidant activity of these extracts. We demonstrated that the highest concentration of this flavonoid was detected in oven-dried samples, although there no significant difference in their pharmacological activity of all analyzed samples could be shown.

Protective effects of three extracts from Antarctic plants against ultraviolet radiation in several biological models.

The photoprotective effect of the methanolic extracts of three Antarctic plant species - Deschampsia antarctica Desv., Colobanthus quitensis (Kunth) Bartl., and Polytrichum juniperinum Hedw. against UV-induced DNA damage was investigated in hamster lung fibroblasts (V79 cells) and in a biomonitor organism Helix aspersas, using comet assay. The protective, mutagenic, and antimutagenic profiles of these extracts were also evaluated using haploid strains of the simple eukaryote Saccharomyces cerevisiae, and antioxidant activity were investigated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging assay, as well as the hypoxanthine/xanthine oxidase assay. At the concentration range employed, the extracts were not cytotoxic or mutagenic to S. cerevisiae. In addition, the treatment with these extracts enhanced survival, and decreased induced reverse, frameshift, and forward mutations in a dose-response manner in all UVC doses employed. The plants extracts did not generate DNA strand breaks in V79 cells, and the treatment significantly decreased DNA damage induced by UVC. Extracts significantly decreased UVC-induced lipid peroxidation in V79 cells, showing a clear antioxidant property. Moreover, results of comet assay in V79 cells, employing Fpg, Endo III, and Endo V enzymes, demonstrated significant reduction of UVC-induced DNA damage after pre-incubation with these extracts. The treatment with all tested extracts were much less efficient against UVC-induced cytotoxicity in the yeast strain defective in photolyase as compared to the wild type strain, suggesting that this DNA repair pathway is stimulated by substances present in the extracts. All extracts showed a significant inhibitory effect in the hypoxanthine/xanthine oxidase assay, and they had the ability to scavenge DPPH. In H. aspersas, the treatment was able to protect against UVC-induced damage. In conclusion, D. antarctica, C. quitensis, and P. juniperinum extracts present photoprotective properties, which can be attributed to molecules, such as flavonoids and carotenoids, which act as UV-absorbing molecules and as antioxidants, as well as stimulate DNA-repair processes.

Pressurized liquid extraction of vitamin E from Brazilian grape seed oil.

The goal of this paper is to optimize the pressurized liquid extraction (PLE) of vitamin E from grape seed oil from residues of the wine industry. For this purpose an experimental planning to optimize the extraction of Brazilian grape seed oil by means of PLE with hexane as solvent was applied and the results are compared with conventional methods (Soxhlet and mechanical press extraction). Vitamin E was separated and analyzed using HPLC with UV detection. This study demonstrates the ability of the PLE in extracting grape seed oil rich in vitamin E.

Antioxidant and antimutagenic properties of the monoterpene indole alkaloid psychollatine and the crude foliar extract of Psychotria umbellata Vell.

Psychollatine is a monoterpene indole alkaloid produced and accumulated by Psychotria umbellata Vell. (Rubiaceae) leaves in relatively high amounts (approximately 3% of the dry weight). The alkaloid has been shown to display opioid-like analgesic, anxiolytic, antidepressive and antipsychotic activities in rodents. In vitro assays suggested a protective role for this molecule in plant oxidative stress responses. This work reports antioxidant properties of psychollatine and the crude foliar extract from P. umbellata in strains of Saccharomyces cerevisiae proficient and deficient in antioxidant defenses exposed to H2O2 and paraquat. The antimutagenic activity of P. umbellata and its main alkaloid were assayed in S. cerevisiae N123 strain in presence of H2O2. Moreover, the antioxidant capacity of these substances on the hydroxyl radical (OH.) was investigated, using the hypoxanthine/xanthine oxidase assay. Psychollatine and the crude foliar extract of P. umbellata showed protective effect against oxidative stress in yeast, acting both as antioxidant and antimutagenic agents.

Protective effects of Hibiscus tiliaceus L. methanolic extract to V79 cells against cytotoxicity and genotoxicity induced by hydrogen peroxide and tert-butyl-hydroperoxide.

Plants of the genus Hibiscus thrives produce a diversity of molecules with bioactive properties. In a previous study of Hibiscus tiliaceus L. methanolic extract (HME) using bacteria and yeast, as test media, it has been shown that HME strongly inhibited the mutagenic action of H(2)O(2) or tert-butyl-hydroperoxide (t-BHP). Here, our interest is to evaluate the genotoxicity and the antigenotoxic/antimutagenic properties of HME using oxidative challenge with H(2)O(2) and t-BHP in V79 cells. We determined cytotoxicity using clonal survival assay; evaluated DNA damage using the comet assay and the micronucleus test in binucleated cells besides of the lipid peroxidation degree and the reduced glutathione content. We examined the ability of HME in quenching hydroxyl radical by means of a HPLC-based method utilizing the hypoxanthine/xanthine oxidase assay. At concentrations ranging from 0.001 to 0.1mg/mL, HME was not cytotoxic, genotoxic or mutagenic. Treatment with non-cytotoxic concentrations of HME increased cell survival after H(2)O(2) and t-BHP exposure and prevented DNA damage. The pre-treatment with HME also was able to decrease the mutagenic effect of these genotoxins, evaluated using the micronucleus test. HME prevented the increase in lipid peroxidation and decrease in GSH content in response to the oxidative challenge. Therefore, the ability in preventing against H(2)O(2)- and t-BHP-induced GSH depletion and lipid peroxidation was probably a major contribution to the cytoprotective effects. Moreover, HME acts as a hydroxyl radical scavenger. In summary, HME did not have a harmful or inhibitory effect on the growth of V79 cells and presented antioxidant activity, consequently, both antigenotoxic and antimutagenic effects against oxidative DNA damage.

Antioxidant properties of beta-carboline alkaloids are related to their antimutagenic and antigenotoxic activities.

The beta-carboline alkaloids found in medical plants and in a variety of foods, beverages and cigarette smoke have a range of action in various biological systems. In vitro studies have demonstrated that these alkaloids can act as scavengers of reactive oxygen species. In this paper, we report the in vivo antioxidative properties of the aromatic (harmane, harmine, harmol) and dihydro-beta-carbolines (harmaline and harmalol) studied by using Saccharomyces cerevisiae strains proficient and deficient in antioxidant defenses. Their antimutagenic activity was also assayed in S. cerevisiae and the antigenotoxicity was tested by the comet assay in V79 cell line, when both eukaryotic systems were exposed to H(2)O(2). We show that the alkaloids have a significant protective effect against H(2)O(2) and paraquat oxidative agents in yeast cells, and that their ability to scavenge hydroxyl radicals contributes to their antimutagenic and antigenotoxic effects.