Igor Vivian de Almeida

Antimutagenic Effect of Medicinal Plants Achillea millefolium and Bauhinia forficata In Vivo

The investigation of traditionally used medicinal plants is valuable both as a source of potential chemotherapeutic drugs and as a measure of safety for the continued use of these medicinal plants. Achillea millefolium L. (AM) is an ancient remedial herb native to Europe that is used to treat wounds, gastrointestinal and hepatobiliary disorders, inflammation, headaches, and pain. Bauhinia forficata Link (BF), an Asiatic plant, is one of the most commonly used plants in folk medicine against diabetes. The aim of this study was to evaluate the cytotoxic and antimutagenic potential of aqueous extracts of AM and BF on bone marrow cells of Wistar rats treated in vivo. These plant extracts possess considerable antioxidant activity due to the presence of flavonoids and phenolic compounds. These compounds were determinants to noncytotoxic and antimutagenic/protective action of these plants, that reduced statistically the percentage of chromosomal alterations induced by the chemotherapeutic agent cyclophosphamide in simultaneous (AM, 68%; BF, 91%), pre- (AM, 68%; BF, 71%), and post-treatment (AM, 67%; BF, 95%). Therefore, the results of this study indicate that extracts of A. millefolium and B. forficata have antimutagenic potential and that their consumption can benefit the health of those using them as an alternative therapy.

Evaluation of the cytotoxicity, mutagenicity and antimutagenicity of a natural antidepressant, Hypericum perforatum L. (St. John's wort), on vegetal and animal test systems.

BackgroundSt. John’s wort (Hypericum perforatum L.) is an herbaceous plant that is native to Europe, West Asia and North Africa and that is recognized and used worldwide for the treatment of mild and moderate depression. It also has been shown to be therapeutic for the treatment of burns, bruises and swelling and can be used for its wound healing, antiviral, antimicrobial, antioxidant, analgesic, hepato-protective and anxiolytic properties. The aim of this study was to evaluate the potential cytotoxic, mutagenic and antimutagenic action of H. Perforatum.MethodsMeristematic cells were used as the test system for Allium cepa L., and bone marrow cells from Rattus norvegicus, ex vivo, were used to calculate the mitotic index and the percentage of chromosomal aberration. Statistical analysis was performed using the chi-square test.ResultsThis medicinal plant had no cytotoxic potential in the vegetal test system evaluated. In the animal test system, none of the acute treatments, including intraperitoneal gavage and subchronic gavage, were cytotoxic or mutagenic. Moreover, this plant presented antimutagenic activity against the clastogenic action of cyclophosphamide, as confirmed in pre-treatment (76% reduction in damage), simultaneous treatment (95%) and post-treatment (97%).ConclusionsThus, the results of this study suggest that the administration of H. perforatum, especially by gavage similar to oral consumption used by humans, is safe and with beneficial antimutagenic potential.

β-(1→3,1→6)-d-glucans produced by Diaporthe sp. endophytes: Purification, chemical characterization and antiproliferative activity against MCF-7 and HepG2-C3A cells.

This study reports the characterization and antiproliferative activity of exopolysaccharides (EPS) produced by submerged cultures of the endophytes Diaporthe sp. JF766998 and Diaporthe sp. JF767007 isolated from the medicinal plant Piper hispidum Sw. Both strains secreted a crude EPS that, upon size exclusion chromatography, showed to contain a heteropolysaccharide (galactose, glucose and mannose) and a high-molecular weight glucan. Data from methylation analysis, FTIR and NMR spectroscopy (1H, COSY, TOCSY and HSQC-DEPT) indicated that the purified glucan consisted of a main chain of glucopyranosyl β-(1→3) linkages substituted at O-6 by glucosyl residues. According to MTT assay, some treatments of both β-glucans have antiproliferative activity against human breast carcinoma (MCF-7) and hepatocellular carcinoma (HepG2-C3A) cells after 24 and 48h of treatment, exhibiting a degree of inhibition ratio that reached the highest values at 400μg/mL: 58.0% (24h) and 74.6% (48h) for MCF-7 cells, and 61.0% (24h) and 83.3% (48h) for HepG2-C3A cells. These results represent the first reports on the characterization and antiproliferative effect of β-glucans from Diaporthe species and also expand the knowledge about bioactive polysaccharides from endophytic sources.

Effect of Processing, Post-Harvest Irradiation, and Production System on the Cytotoxicity and Mutagenicity of Vitis labrusca L. Juices in HTC Cells

The juices of grapes (Vitis labrusca L.) are similar to the fruit itself because the main constituents of the fruit are present in the juice. However, their quality characteristics may be modified by the harsh technological processes used for the production of integral food, such as production systems of raw materials and post-harvest treatment of grapes with ultraviolet (UV) irradiation. Therefore, the present study analyzed juices produced naturally (by liquefying the fruit) or by the technological process of extraction by steam distillation (90°C) of grapes from organic and conventional production systems that were untreated or treated with UV type C (65.6 J/m2 for 10 minutes). Using cultures of Rattus norvegicus hepatoma cells (HTC) in vitro, cytotoxic effects were assayed by the MTT test and by calculating the cytokinesis blocked proliferation index (CBPI), and mutagenic effects were measured by the cytokinesis block micronucleus assay. The results of the MTT assay and the CBPIs indicated that none of the juices were cytotoxic, including those that induced cell proliferation. The results of the micronucleus assay showed that none of the juices were mutagenic. However, the average number of micronuclei was lower in the juices produced from organic grapes, and cell proliferation, soluble acids and phenolic compounds were significantly higher. Compared with the natural juices, the integral juices of conventional grapes showed a higher average number of micronuclei as well as lower stimulation of cell proliferation and lower levels of bioactive compounds. The results demonstrate a beneficial effect of UV-C irradiation of post-harvest grapes in stimulating the synthesis of nutraceutical compounds without generating cytotoxic or mutagenic substances. Taken together, our findings support the consumption of grape juice and the application of food production techniques that enhance its nutritional value and promote its production, marketing and consumption.

Cytotoxicity, mutagenicity, and antimutagenicity of the gentisic acid on HTC cells.

Abstract Gentisic acid (GA) exhibits antioxidant, anti-inflammatory, and antibiotic activities. This substance can be found in citrus fruits, grapes, olive oil, and peas. Considering that there are few studies in the literature on the toxicity of GA, the present work aimed to investigate its cytotoxic, mutagenic, and antimutagenic activities on HTC cells. GA was diluted in culture medium at the final concentration of 0.08, 0.16, 0.8, 1.6, and 8 μg/mL. The cytotoxicity was determined by the MTT assay and Trypan Blue exclusion method, with methyl methanesulfonate and doxorubicin as positive controls, respectively. The cytokinesis-block micronucleus assay determined the mutagenic/antimutagenic activity with benzo[a]pyrene as positive control. Negative control received culture medium only. GA (0.08–8 μg/mL) was not cytotoxic to HTC cells by the MTT assay nor the Trypan Blue exclusion method as no statistical difference was observed when compared to the control. Concentration of 0.08 and 0.8 μg/mL showed no mutagenic or clastogenic effects, as no significant micronuclei inductions were observed, different from 8 μg/mL, that was mutagenic. Furthermore, none of the concentrations presented an antiproliferative activity. The antimutagenic activity of GA (0.08 μg/mL) was observed at the simultaneous treatment, as it reduced the frequency of micronuclei by 76% (24 h) and 79% (48 h). Although pre- and post-treatments were not statistically different from the mutagen, they reduced the induced-damage by 11% and 21%, respectively. The present study indicated the absence of cytotoxicity and antiproliferative activities of GA, in addition to their antimutagenic/protective effects that may contribute to human health.

Evaluation of the Anticancer Activities of the Plant Alkaloids Sanguinarine and Chelerythrine in Human Breast Adenocarcinoma Cells

BACKGROUND Breast cancer is associated with a high mortality rate around the world due to its aggressiveness and high resistance to conventional therapies. Sanguinarine (SAN) and Chelerythrine (CHE) are plant alkaloids extracted from Sanguinaria canadensis and Macleaya cordata, which have been studied for their bioactivities. OBJECTIVE To determine the anticancer activities of Sanguinarine (SAN) and Chelerythrine (CHE) plant alkaloids. METHOD The MTT assay, the alkaline comet assay and cell cycle analyses by flow cytometry were performed. RESULTS It was observed that SAN was cytotoxic to human breast adenocarcinoma cells (MCF-7) at concentrations of 7.5 µM (24 and 48 hours), effectively reducing cell viability from the concentration of 10 µM for 24 hours and 7.5 µM for 48 hours, by the MTT test. CHE, in turn, was cytotoxic at concentrations of 10 and 20 µM (48 hours), but did not compromise the cellular viability. The comet assay indicated that SAN was genotoxic to the MCF-7 cells, with a significant increment of damage at 10 µM, while none of the tested concentrations of CHE showed a genotoxic effect. The flow cytometry analysis indicated that no cell cycle arrest was caused by both alkaloids, but SAN 10 µM induced a sub-G1 cell population. CONCLUSION The results of cytotoxicity, genotoxicity and cell cycle monitoring that are presented in this paper have suggested that SAN has more of a chemotherapeutic activity, as well as having the potential for the development of new therapies for breast cancer, when compared to CHE.

Evaluation of cytotoxicity and mutagenicity of the benzodiazepine flunitrazepam in vitro and in vivo

Flunitrazepam (FNZ) e um sedativo benzodiazepinico prescrito para o tratamento da insonia em curto prazo. Entretanto, existe a preocupacao com relacao aos possiveis efeitos carcinogenicos ou genotoxicos causados por este farmaco. Entao, o objetivo deste estudo foi avaliar os efeitos citotoxicos, clastogenicos e aneugenicos do FNZ em celulas de hepatoma de Rattus norvegicus (HTC) in vitro e em celulas de medula ossea de ratos Wistar in vivo. Foram testadas as concentracoes de 0,2, 1,0 e 10 μg/mL de FNZ pelo teste do micronucleo com bloqueio de citocinese in vitro e 7, 15 e 30 μg/mL/kg de peso corporeo para o teste de aberracao cromossomica in vivo. Os resultados mostraram que as concentracoes do benzodiazepinico testadas nao foram citotoxicas, aneugenicas ou clastogenicas. Entretanto, considerando os efeitos adversos do uso deste benzodiazepinico, mais estudos sao necessarios.