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The skin secretion from toads of the Bufonidae family has great potential in the search for new active compounds to be used as drug candidates in treating some diseases, among them cancer. In this context, this study aimed to evaluate the cytotoxic and antimutagenic activity of the parotoid gland secretion extracts of Rhinella marina and Rhaebo guttatus, as well as biochemically analyze transaminases and serum creatinine for liver and renal damage, respectively. Cytotoxicity was performed by the colorimetric method based on MTT (3- [4, 5-dimethyl-2-thiazolyl]-2, 5-diphenyl-2H-tetrazolium bromide) with different concentrations of the extracts in Walker or splenic tumor cell cultures from rats and mice. The micronucleus test was performed with male Swiss mice treated orally with the extracts for 15 days, and then intraperitoneally with N-ethyl-N-nitrosurea (50 mg kg-1). Micronucleated polychromatic erythrocytes (MNPCE) were evaluated in bone marrow. The extracts showed cytotoxic activity in the evaluated cells. There was a significant reduction in the frequency of MNPCE (R. marina = 56% and R. guttatus = 75%, p < 0.001), indicating antimutagenic potential of the extracts. The groups treated only with extract showed an increase in MNPCE frequency, evidencing mutagenic potential. Biochemical analyzes showed no significant difference between treatments. Thus, under our experimental conditions, the extracts of R. marina and R. guttatus skin secretions presented chemopreventive potential for cancer. (AU)

A secreção cutânea de anuros da família Bufonidae tem grande potencial na busca de novos compostos ativos para utilização como fármacos candidatos no tratamento de algumas doenças, entre elas o câncer. Neste contexto, este estudo teve como objetivo avaliar a atividade citotóxica e antimutagênica dos extratos da secreção da glândula parótida de Rhinella marina e Rhaebo guttatus, bem como a análise bioquímica de transaminases e creatinina séricas, para avaliar dano hepático e renal, respectivamente. A avaliação de citotoxicidade foi realizada pelo método colorimétrico baseado no MTT (3-[4, 5-dimethyl-2-thiazolyl]-2, 5-diphenyl-2H-tetrazolium bromide), com diferentes concentrações dos extratos em culturas de células do Tumor de Walker ou células esplênicas de rato e camundongo. O teste do micronúcleo foi realizado com camundongos Swiss machos que receberam tratamento oral com os extratos durante 15 dias, seguido de tratamento intraperitoneal com N-etil-N-nitrosuréia (50 mg kg-1). A frequência de eritrócitos policromáticos micronucleados (PCEMN) foi determinada em medula óssea. Os extratos apresentaram ação citotóxica nas células avaliadas. Houve uma redução significativa na frequência de PCEMN (R. marina = 56% e R. guttatus = 75%, p < 0,001), observando-se um potencial antimutagênico dos extratos. Os grupos tratados somente com os extratos apresentaram um aumento na frequência de PCEMNs, evidenciando um potencial mutagênico. As análises bioquímicas não apresentaram diferença significativa entre os tratamentos. Assim, nas condições experimentais testadas, as secreções cutâneas de R. marina e R. guttatus apresentaram potencial quimiopreventivo para câncer.(AU)

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BACKGROUND: Camu-camu (Myrciaria dubia) is a typical Amazonian fruit and has high antioxidant capacity due to its high levels of vitamin C and phenolic compounds. This study aimed to determine the phytochemicals, antioxidant capacity and antimutagenic effects of camu-camu fruits with different maturity stages grown in dry (commercial cultivation) or flooded environments (native cultivation, Amazon). RESULTS: Total polyphenols, ascorbic acid and in vitro antioxidant capacity levels were higher in ripe fruits grown in a commercial cultivation. The extracts from ripe camu-camu grown in a commercial cultivation exerted antioxidant effects and high percentage of protection against doxorubicin and 1,2-dimethylhydrazine in all tested systems (liver, bone marrow and gut), for three camu-camu extract concentrations (17, 85 and 170 mg kg-1 body weight), as follows: bone marrow minocronucleus (37.91%, 41.75%, 43.95%); micronucleus gut test (61.01%, 64.40%, 50.28%); apoptosis index (60.26%, 62.44%, 58.22%); comet assay through the tail moment (71.64%, 72.31%, 70.70%), percent DNA in the tail (64.54%, 68.75%, 76.79%) and tail intensity (76.43%, 81.02%, 68.33%). CONCLUSION: The results of this study contribute to increasing the production of camu-camu fruits grown in dry environments and their use as a health-promoting food. © 2018 Society of Chemical Industry.

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In this work, we investigated the usefulness of the SOS Chromotest for screening plant antigenotoxic agents against ultraviolet radiation (UV). Fifty Colombian plant extracts obtained by supercritical fluid (CO2) extraction, twelve plant extract constituents (apigenin, carvacrol, ß-caryophyllene, 1,8-cineole, citral, p-cymene, geraniol, naringenin, pinocembrin, quercetin, squalene, and thymol) and five standard antioxidant and/or photoprotective agents (curcumin, epigallocatechin gallate, resveratrol, α-tocopherol, and Trolox®) were evaluated for their genotoxicity and antigenotoxicity against UV using the SOS Chromotest. None of the plant extracts, constituents or agents were genotoxic in the SOS Chromotest at tested concentrations. Based on the minimal extract concentration that significantly inhibited UV-genotoxicity (CIG), five plant extracts were antigenotoxic against UV as follows: Baccharis nítida (16 µg mL-1) = Solanum crotonifolium (16 µg mL-1) > Hyptis suaveolens (31 µg mL-1) = Persea caerulea (31 µg mL-1) > Lippia origanoides (62 µg mL-1). Based on CIG values, the flavonoid compounds showed the highest antigenotoxic potential as follows: apigenin (7 µM) > pinocembrin (15 µM) > quercetin (26 µM) > naringenin (38 µM) > epigallocatechin gallate (108 µM) > resveratrol (642 µM). UV-genotoxicity inhibition with epigallocatechin gallate, naringenin and resveratrol was related to its capability for inhibiting protein synthesis. A correlation analysis between compound antigenotoxicity estimates and antioxidant activity evaluated by the oxygen radical absorbance capacity (ORAC) assay showed that these activities were not related. The usefulness of the SOS Chromotest for bioprospecting of plant antigenotoxic agents against UV was discussed.

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Milk-derived bioactive peptides with a single activity (e.g., antioxidant, immunomodulatory, or antimicrobial) have been previously well documented; however, few studies describe multifunctional bioactive peptides, which may be preferred over single-activity peptides, as they can simultaneously trigger, modulate, or inhibit multiple physiological pathways. Hence, the aim of this study was to assess the anti-inflammatory, antihemolytic, antioxidant, antimutagenic, and antimicrobial activities of crude extracts (CE) and peptide fractions (<3 and 3-10 kDa) obtained from fermented milks with specific Lactobacillus plantarum strains. Overall, CE showed higher activity than both peptide fractions (<3 and 3-10 kDa) in most of the activities assessed. Furthermore, activity of <3 kDa was generally higher, or at least equal, to the 3 to 10 kDa peptide fractions. In particular, L. plantarum 55 crude extract or their fractions showed the higher anti-inflammatory (723.68-1,759.43µg/mL of diclofenac sodium equivalents), antihemolytic (36.65-74.45% of inhibition), and antioxidant activity [282.8-362.3µmol of Trolox (Sigma-Aldrich, St. Louis, MO) equivalents]. These results provide valuable evidence of multifunctional role of peptides derived of fermented milk by the action of specific L. plantarum strains. Thus, they may be considered for the development of biotechnological products to be used to reduce the risk of disease or to enhance a certain physiological function.

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ABSTRACT Tabernaemontana catharinensis A. DC (Apocynaceae) is used as a medicinal plant by the population. In order to contribute to the safe use of the plant as herbal medicine, this study aimed to morphoanatomically characterize the aereal vegetative organs of T. catharinensis and to evaluate the leaves’ mutagenic and antimutagenic activities. Histological blades of leaves and stem of T. catharinensis were performed; the methionine system (methG1) and Aspergillusnidulans conidia germination analysis were employed for mutagenic and antimutagenic evaluation. The morphoanatomic analysis did not show trichomes in the stem, petiole and leaf. Besides, it was observed both the presence of bi-collateral bundles - except in the foliar apex where the bundles were from the collateral type - as well as anamphistomatic leaf with paracyte stomata and sub-epidermal layer in the region of the leaf edges. The mutagenicity/antimutagenicity trial indicated a significant decrease of mutation frequency in comparison with the control group and showed that the T. catharinensis had antimutagenic activity within the type, time and form of treatment. Since the germination test showed that the conidia germination was accelerated from the bud phase, activities at the cell cycle level and polarized growth proved to be possible. The morphoanatomic analysis of the leaf and stem associated with the mutagenic and antimutagenic analyses contributes to the safe use of the plant by humans and also for the quality control of a possible phytotherapeutic drug.

RESUMO Tabernaemontana catharinensis A. DC (Apocynaceae) é utilizada como planta medicinal pela população. A fim de contribuir para o uso seguro da planta como medicinal, este trabalho teve como objetivo caracterizar morfoanatomicamente os órgãos vegetativos aéreos de T. catharinensis e avaliar a atividade mutagênica e antimutagênica de suas folhas. Foram realizados cortes histológicos da folha e do caule de T. catharinensis e, para a avaliação mutagênica e antimutagênica, foi utilizado o sistema metionina (methG1) e análise da germinação de conídios em Aspergillus nidulans. A análise morfoanatômica evidenciou a ausência de tricomas no caule, pecíolo e folha; presença de feixes bicolaterais, com exceção no ápice foliar cujos feixes são do tipo colateral; folha anfiestomática com estômatos paracíticos e camada subepidérmica na região do bordo foliar. O ensaio de mutagenicidade/antimutagenicidade mostrou uma diminuição significativa da frequência de mutação em relação ao controle, indicando que nesse tipo, tempo e forma de tratamento, T. catharinensis apresentou atividade antimutagênica. O ensaio de germinação evidenciou que houve aceleração da germinação dos conídios, a partir da fase de botão, indicando uma possível atuação em nível de ativação de ciclo celular e crescimento polarizado. A análise morfoanatômica da folha e do caule associados à análise mutagênica e antimutagênica, contribuem para o uso seguro da planta pela população e para o controle de qualidade de um possível fitoterápico.

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BACKGROUND: In various regions of Brazil, several species of the genus Byrsonima (Malpighiaceae) are widely used to treat gastrointestinal complications. This genus has about 150 species of shrubs and trees distributed over the entire Neotropical region. Various biological activities have been identified in these plants, especially antioxidant, antimicrobial and topical and systemic anti-inflammatory activities. The aim of this study was to investigate the mutagenicity and antimutagenicity of hydroalcoholic leaf extracts of six species of Byrsonima: B. verbascifolia, B. correifolia, B. coccolobifolia, B. ligustrifolia, B. fagifolia and B. intermedia by the Salmonella microsome assay (Ames test). METHODS: Mutagenic and antimutagenic activity was assessed by the Ames test, with the Salmonella typhimurium tester strains TA100, TA98, TA97a and TA102, with (+S9) and without (-S9) metabolization, by the preincubation method. RESULTS: Only B. coccolobifolia and B. ligustrifolia showed mutagenic activity. However, the extracts of B. verbascifolia, B. correifolia, B. fagifolia and B. intermedia were found to be strongly antimutagenic against at least one of the mutagens tested. CONCLUSIONS: These results contribute to valuable data on the safe use of medicinal plants and their potential chemopreventive effects. Considering the excellent antimutagenic activities extracted from B. verbascifolia, B. correifolia, B. fagifolia and B. intermedia, these extracts are good candidate sources of chemopreventive agents. However, B. coccolobifolia and B. ligustrifolia showed mutagenic activity, suggesting caution in their use.

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Benzo[alpha]pyrene (B[α]P) was used to test the possible antimutagenic effects of Arthrospira (Spirulina) maxima (SP) on male and female mice. SP was orally administered at 0, 200, 400, or 800 mg/kg of body weight to animals of both sexes for 2 weeks before starting the B[α]P (intraperitoneal injection) at 125 mg/kg of body weight for 5 consecutive days. For the male dominant lethal test, each male was caged with two untreated females per week for 3 weeks. For the female dominant lethal test, each female was caged for 1 week with one untreated male. All the females were evaluated 13-15 days after mating for incidence of pregnancy, total corpora lutea, total implants and pre- and postimplant losses. SP protected from B[α]P-induced pre- and postimplant losses in the male dominant lethal test, and from B[α]P-induced postimplantation losses in treated females. Moreover, SP treatment significantly reduced the detrimental effect of B[α]P on the quality of mouse semen. Our results illustrate the protective effects of SP in relation to B[α]P-induced genetic damage to germ cells. We conclude that SP, owing mainly to the presence of phycocyanin, could be of potential clinical interest in cancer treatment or prevention of relapse.

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A espécie Ocimum gratissimum L., popularmente conhecida como alfavaca, é uma planta muito usada na medicina tradicional brasileira, à qual são atribuídas diversas atividades terapêuticas quando usada na forma de infuso de suas folhas. Neste estudo foi realizada a caracterização fitoquímica, a avaliação da ação antioxidante e a investigação dos efeitos antimutagênico e antigenotóxico, além do efeito mutagênico e genotóxico potencial do extrato aquoso liofilizado a parir das folhas de O. gratissimum (EAOG). O conteúdo de polifenóis totais no extrato foi determinado pelo método Folin-Ciocalteu, sendo encontrado 11,3 µg EAG/mg de EAOG. A atividade antioxidante foi avaliada pelo teste do 1,1-difenil-2-picril hidrazil (DPPH•), apresentando IC50 de 83,0 µg/mL. A antimutagenicidade e mutagenicidade foram avaliadas em cepas de Salmonella typhimurium (TA98 e TA100) utilizando o teste Salmonella/microssoma (Salmonella typhimurium/microssomas) em diferentes concentrações. EAOG induziu a atividade antimutagênica para a cepa TA98. A mutagenicidade não foi observada para o extrato em ambas as linhagens. Adicionalmente, a ação antigenotoxica avaliada pelo teste de clivagem do DNA-plasmidial também foi observada para EAOG. Os resultados também demonstraram que o extrato não foi capaz de induzir a genotoxicidade pelo teste empregado. Este estudo relata, pela primeira vez, as propriedades antimutagênica e antigenotóxica do extrato aquoso de O. gratissimum.

The species Ocimum gratissimum L., popularly known as Clove Basil, is a plant widely used in traditional Brazilian medicine, and several therapeutic activities are attributed to it when used as infusion of its leaves. In this study, we carried out a phytochemical characterization and the assessment evaluation and investigation of the antioxidant action of the antimutagenic and antigenotoxic effects and the potential mutagenic and genotoxic effects of the freeze-dried aqueous extract of the O. gratissimum (EAOG) leaves. The total polyphenol content in the extract was determined by the Folin-Ciocalteu method, and we found 11.3 µg EAG/mg of EAOG. The antioxidant activity was assessed by the 1,1-diphenyl-2-picryl hidrazil (DPPH·), with IC50 of 83.0 µg/mL. Antimutagenicity and mutagenicity were assessed in Salmonella typhimurium (TA98 and TA100) strains using the Salmonella/microsome (Salmonella typhimurium/microsome) test in different concentrations. EAOG induced antimutagenic activity for strain TA98. Mutagenicity was not observed for the extract in both strains. Additionally, antigenotoxic action, assessed by cleavage of the DNA-damage, was also observed for EAOG. The results also show that the extract was not able to induce genotoxicity by the test used. This study reports for the first time the antimutagenic and antigenotoxic properties of the O. gratissimum aqueous extract.

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The effect of culinary-medicinal Royal Sun Agaricus (Agaricus brasiliensis) hot water extract on methyl methane sulfonate (MMS) induced mutagenicity/genotoxity in Drosophila melanogaster was studied using a quick and broadly applicable in vivo assay, i.e., the wing somatic mutation and recombination test. We used 2nd instar larvae, trans-heterozygous for the third chromosome recessive markers, i.e., multiple wing hairs (mvh) and flare-3 [flr (3)], and fed them for 24 h with the aqueous extract of A. brasiliensis. For antigenotoxicity studies a 24-h pretreatment with the extract was done, followed by a 48-h treatment of the then 3rd instar larvae with MMS. The frequency of mutations of the wing blade changes (i.e., of the number of wing spots of different sizes) induced in somatic cells was determined as a parameter of genetic changes of the wing imaginal discs. The results showed that A. brasiliensis extract did not cause any genotoxic or mutagenic effects. No antigenotoxic and/or protective effect against the induction of mutations by MMS was observed. Instead, a possible enhanced mitotic recombination frequency by MMS was seen after pretreatment of the larvae with A. brasiliensis extract. Possible mechanisms of action are discussed.

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A Tabebuia impetiginosa, conhecida popularmente como ipê-roxo, é uma planta nativa das florestas tropicais chuvosas da América do Sul e Central. Componentes químicos obtidos da casca têm mostrado efeito terapêutico, como antiinflamatório, antifúngico e antibacteriano. Porém, pela falta de dados na literatura, pouco se sabe sobre os efeitos do extrato das flores. Assim, o objetivo do presente trabalho foi avaliar o potencial mutagênico e antimutagênico do extrato obtido das flores da T. impetiginosa, em três diferentes concentrações (100, 300 e 500 mg kg-1 p.c.) pelo teste do micronúcleo. Para o teste de mutagenicidade, a doxorrubicina (DXR, 90 mg kg-1 p.c.) foi utilizada como indutor de danos no DNA e para o teste de antimutagenicidade, os tratamentos com o extrato foram realizados simultaneamente com este agente químico. O sangue periférico dos animais foi coletado 24 horas após os tratamentos. A comparação da frequência de eritrócitos policromáticos (PCEs) em 400 eritrócitos/animal entre os diferentes grupos não demonstrou qualquer citotoxicidade do extrato. Em relação às frequências de micronúcleos em PCEs (PCEMNs), não foram observadas diferenças significativas entre os grupos tratados com as diferentes concentrações de extrato e o controle negativo. Da mesma forma, todos os grupos de animais que receberam os tratamentos simultâneo do extrato (100, 300 ou 500 mg kg-1 p.c.) com a DXR, apresentaram valores de PCEMNs muito próximos quando comparados com os dados observados no grupo de animais que recebeu somente a DXR. Esses resultados apresentados indicam ausência de efeito mutagênico e antimutagênico do extrato obtido das flores da T. impetiginosa em sistema teste in vivo.

T. impetiginosa, known as "ipê-roxo", is a plant native to tropical rain forests of Central and South Americas. Chemical compounds obtained from its bark have shown anti-inflammatory, antifungal and antibacterial therapeutic effect. However, due to the lack of data in the literature, little is known about the effects of its flower extract. Thus, the aim of this study was to evaluate the mutagenic and antimutagenic potential of the extract obtained from T. impetiginosa flowers at three different concentrations (100, 300 and 500 mg kg-1 p.c.) by the micronucleus test. For the mutagenicity test, doxorubicin (DXR, 90 mg kg-1 p.c.) was used as DNA-damage inducer, while for the antimutagenicity test, treatments with the extract were performed simultaneously with this chemical agent. The peripheral blood of animals was collected 24 hours after the treatments. The frequency of polychromatic erythrocytes (PCEs) in 400 erythrocytes/animal was compared among the different groups and showed no extract cytotoxicity. As regards the frequency of micronuclei in PCEs (PCEMNs), there were no significant differences between the groups treated with different concentrations of extract and the negative control. Similarly, all groups of animals that received the simultaneous extract treatments (100, 300 or 500 mg kg-1 p.c.) with DXR showed very similar values of PCEMNs when compared with the data observed for the group of animals that received DXR alone. These results indicate no mutagenic and antimutagenic effect of the extract obtained from T. impetiginosa flowers in the testing system in vivo.

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