Rodrigo Juliano Oliveira

Effects of the polysaccharide β-glucan on clastogenicity and teratogenicity caused by acute exposure to cyclophosphamide in mice.

Alterations that could lead to the cancer development may also be related to an adverse development of offspring in experimental animals. Some functional foods, which contain the polysaccharide beta-glucan, have been described as being effective in the prevention of clastogenic damage. Based on that finding, the aim of the present study was to determine the efficacy of this sugar polymer in the mutagenic and teratogenic damage control. Two sets of females, pregnant and non-pregnant, were evaluated. The results indicated that beta-glucan was effective in preventing clastogenic damage in pregnant as well as non-pregnant females. In addition, pregnant females were more susceptible to mutagenic damage. However, teratogenic effects were not prevented effectively, although there was a trend toward a reduction in level of malformations. Despite beta-glucan did not prevent malformations, it increased fetal viability and reduced number of post-implantation losses and resorption, thereby enhancing reproductive performance in females.

Activity of selenium on cell proliferation, cytotoxicity, and apoptosis and on the expression of CASP9, BCL-XL and APC in intestinal adenocarcinoma cells

Intestinal cancers are correlated with diet. Thus, determining and understanding nutrient-genome interactions is important. The present work assessed the action of the oligoelement selenium on cell proliferation, cytotoxicity, and in situ apoptosis induction and on the expression CASP9, BCL-XL and APC genes in intestinal adenocarcinoma cells (HT29). HT29 cells were cultured and treated with selenium at concentrations of 5, 50 and 500ng/mL with or without the damage-inducing agent doxorubicin. These cells were then evaluated for cytotoxicity (MTT), cell proliferation and in situ apoptosis induction. To evaluate gene expression, only the cells treated with 500ng/mL of selenium were used. RNA was extracted from these cells, and the expressions of CASP9, BCL-XL and APC were analyzed by the RT-PCR method. The GAPDH gene was used as a reference gene. The MTT assay showed that selenium was not cytotoxic at any of the concentrations tested. The cell proliferation assay showed that selenium did not interfere with cell proliferation at the three concentrations tested. In contrast, when the three concentrations were combined with doxorubicin, a significant decrease in the proliferation rate was observed. The apoptosis rate was significantly increased in the selenium (500ng/mL) and doxorubicin group. CASP9 expression was increased and BCL-XL expression decreased in the selenium (500ng/mL) and doxorubicin group. APC was significantly increased in the selenium group alone. These results show that selenium increases apoptosis, especially when it is associated with a damage-inducing agent. Also, selenium has an important role in the expression of the APC gene, which is related to cell cycle regulation.

Antigenotoxic and antimutagenic effects of Schinus terebinthifolius Raddi in Allium cepa and Swiss mice: a comparative study.

It is estimated that 60% of anticancer drugs are derived directly or indirectly from medicinal plants. Schinus terebinthifolius Raddi (Anacardiaceae) is traditionally used in Brazilian medicine to treat inflammation, ulcers, and tumors. Because of the need to identify new antimutagenic agents and to determine their mechanism of action, this study evaluated the chemopreventive activity of the methanolic extract from leaves of S. terebinthifolius (MEST) in Allium cepa cells and in Swiss mice analyzing different protocols of MEST in association with DNA-damaging agents. The antigenotoxic and antimutagenic aspects in peripheral blood were evaluated using the comet and micronucleus assays, respectively. The percentage of damage reduction was used to compare the A. cepa and mice results. Our results showed for the first time that MEST can act as a chemopreventive compound that promotes cellular genome integrity by desmutagenic and bioantimutagenic activities in vegetal and animal models. This finding may therefore have therapeutic applications that can indirectly correlate to the prevention and/or treatment of the degenerative diseases such as cancer.

Evaluation of the antimutagenic and anticarcinogenic effects of inulin in vivo

The incidence of colorectal cancer is growing worldwide. The characterization of compounds present in the human diet that can prevent the occurrence of colorectal tumors is vital. The oligosaccharide inulin is such a compound. The aim of this study was to evaluate the antigenotoxic, antimutagenic and anticarcinogenic effects of inulin in vivo. Our study is based on 3 assays that are widely used to evaluate chemoprevention (comet assay, micronucleus assay, and aberrant crypt focus assay) and tests 4 protocols of treatment with inulin (pre-treatment, simultaneous, post-treatment, and pre + continuous). Experiments were carried out in Swiss male mice of reproductive age. In order to induce DNA damage, we used the pro-carcinogenic agent 1,2-dimethylhydrazine. Inulin was administered orally at a concentration of 50 mg/kg body weight following the protocols mentioned above. Inulin was not administered to the control groups. Our data from the micronucleus assay reveal antimutagenic effects of inulin in all protocols. The percentage of inulin-induced damage reduction ranged from 47.25 to 141.75% across protocols. These data suggest that inulin could act through desmutagenic and bio-antimutagenic mechanisms. The anticarcinogenic activity (aberrant crypt focus assay) of inulin was observed in all protocols and the percentages of damage reduction ranged from 55.78 to 87.56% across protocols. Further tests, including human trials, will be necessary before this functional food can be proven to be effective in the prevention and treatment of colon cancer.

Evaluation of the antimutagenic activity and mode of action of the fructooligosaccharide inulin in the meristematic cells of Allium cepa culture.

This study evaluated the mutagenicity and antimutagenicity of inulin in a chromosomal aberration assay in cultures of the meristematic cells of Allium cepa. The treatments evaluated were as follows: negative control--seed germination in distilled water; positive control--aqueous solution of methyl methanesulfonate (10 μg/mL MMS); mutagenicity--aqueous solutions of inulin (0.015, 0.15, and 1.50 μg/mL); and antimutagenicity--associations between MMS and the different inulin concentrations. The antimutagenicity protocols established were pre-treatment, simultaneous simple, simultaneous with pre-incubation, and post-treatment. The damage reduction percentage (DR%) was 43.56, 27.77, and 55.92% for the pre-treatment; -31.11, 18.51, and 7.03% for the simultaneous simple; 30.43, 19.12, and 21.11% for the simultaneous with pre-incubation; and 64.07, 42.96, and 53.70% for the post-treatment. The results indicated that the most effective treatment for inhibiting damages caused by MMS was the post-treatment, which was followed by the pre-treatment, suggesting activity by bioantimutagenesis and desmutagenesis. The Allium cepa assay was demonstrated to be a good screening test for this type of activity because it is easy to perform, has a low cost, and shows DR% that is comparable to that reported studies that evaluated the prevention of DNA damage in mammals by inulin.

A new synthetic resorcinolic lipid 3-Heptyl-3,4,6-trimethoxy-3H-isobenzofuran-1-one: Evaluation of toxicology and ability to potentiate the mutagenic and apoptotic effects of cyclophosphamide

Resorcinolic lipids have important biological actions, including anti-carcinogenic activity. Therefore, we evaluated the mutagenic, genotoxic, immunomodulatory and apoptotic potential and the biochemical and histopathological changes caused by the synthetic resorcinolic lipid 3-Heptyl-3,4,6-trimethoxy-3H-isobenzofuran-1-one, (AMS35AA; 10, 20 and 40 mg/kg) alone or in combination with cyclophosphamide (100 mg/kg) in Swiss mice. The results indicated that AMS35AA is not genotoxic or mutagenic and does not alter liver or kidney histology. However, the compound does cause an increase (p < 0.05) in the levels of glutamic-oxaloacetic transaminase and creatinine and in splenic phagocytosis and liver and kidney apoptosis. When combined with cyclophosphamide, AMS35AA caused increased (p < 0.05) mutagenic damage (although the compound had anti-genotoxic activity), splenic phagocytosis, neutropenia and glutamic-oxaloacetic transaminase and creatinine levels (even in the absence of histological damage) and induced liver and kidney apoptosis. We conclude that this resorcinolic lipid may be an important chemotherapy adjuvant that can potentiate mutagenic damage and increase apoptosis caused by cyclophosphamide without causing adverse effects. In addition, the immunomodulatory activity of the compound should be noted, which counters reductions in lymphocyte number, a primary side effect of cyclophosphamide in cancer therapy.

Diaryl sulfide analogs of combretastatin A-4: Toxicogenetic, immunomodulatory and apoptotic evaluations and prospects for use as a new chemotherapeutic drug.

Combretastatin A-4 exhibits efficient anti-cancer potential in human tumors, including multidrug-resistant tumors. We evaluated the mutagenic, apoptotic and immunomodulatory potential of two diaryl sulfide analogs of combretastatin A-4, 1,2,3-trimethoxy-5-([4-methoxy-3-nitrophenyl]thio)benzene (analog 1) and 1,2,3-trimethoxy-5-([3-amino-4-methoxyphenyl]thio)benzene (analog 2), as well as their association with the anti-tumor agent cyclophosphamide, in Swiss mice. Such evaluation was achieved using the comet assay, peripheral blood micronucleus test, splenic phagocytosis assay, and apoptosis assay. Both analogs were found to be genotoxic, mutagenic and to induce apoptosis. They also increased splenic phagocytosis, although this increase was more pronounced for analog 2. When combined with cyclophosphamide, analog 1 enhanced the mutagenic and apoptotic effects of this anti-tumor agent. In contrast, analog 2 did not enhance the effects of cyclophosphamide and prevented apoptosis at lower doses. These data suggest that analog 1 could be an adjuvant chemotherapeutic agent and possibly improve the anti-neoplastic effect of cyclophosphamide. Additionally, this compound could be a candidate chemotherapeutic agent and/or an adjuvant for use in combined anti-cancer therapy.

Gestational exposure to Byrsonima verbascifolia: teratogenicity, mutagenicity and immunomodulation evaluation in female Swiss mice.

ETHNOPHARMACOLOGICAL RELEVANCE Byrsonima verbascifolia is used in folk medicine to treat diarrhea, intestinal infections, chronic wounds, Chagas disease, inflammation and as a diuretic. However there is no investigation regarding the Byrsonima verbascifolia hydrometanolic extract (BVHME) used during gestation. MATERIALS AND METHODS The pregnant females were randomly divided into 5 groups. Control group received saline plus DMSO (1%) in a volume of 0.1 mL/10 g (b.w.), via gavage, for at least 15 days prior to mating and throughout the gestational period. The Pre-treatment group received the BVHME, via gavage, at a dose of 50 mg/kg (b.w.) for at least 15 days prior to mating and up to the appearance of the vaginal plug. The Organogenesis group received the BVHME at a dose of 50 mg/kg (b.w.), via gavage, on the 5-15th gestational day. The Gestational group received the BVHME at a dose of 50 mg/kg (b.w.), via gavage, throughout the gestational period (from the 1st to the 18th day of pregnancy). The Pre+Gestational group received the BVHME at a dose of 50mg/kg (b.w.), via gavage, for at least 15 days prior to mating and up to throughout the gestational period. The clinical signals of maternal and fetuses toxicity were evaluated, as the mutagenicity and immunomodulation tests were performed. RESULTS AND CONCLUSIONS The present investigation shows, for the first time, that the use of Byrsonima verbascifolia extract in pregnant Swiss mice, did not alter the female reproductive function, mutagenicity or immunostimulation as well as not interfere with embryofetal development at least in our experimental conditions.

Effects of β-glucan polysaccharide revealed by the dominant lethal assay and micronucleus assays, and reproductive performance of male mice exposed to cyclophosphamide.

β-glucan is a well-known polysaccharide for its chemopreventive effect. This study aimed to evaluate the chemopreventive ability of β-glucan in somatic and germ cells through the dominant lethal and micronucleus assays, and its influence on the reproductive performance of male mice exposed to cyclophosphamide. The results indicate that β-glucan is capable of preventing changes in DNA in both germ cells and somatic ones. Changes in germ cells were evaluated by the dominant lethal assay and showed damage reduction percentages of 46.46% and 43.79% for the doses of 100 and 150 mg/kg. For the somatic changes, evaluated by micronucleus assay in peripheral blood cells in the first week of treatment, damage reduction percentages from 80.63–116.32% were found. In the fifth and sixth weeks, the percentage ranged from 10.20–52.54% and −0.95–62.35%, respectively. Besides the chemopreventive efficiency it appears that the β-glucan, when combined with cyclophosphamide, is able to improve the reproductive performance of males verified by the significant reduction in rates of post-implantation losses and reabsorption in the mating of nulliparous females with males treated with cyclophosphamide.

Gochnatia polymorpha ssp. floccosa: bioprospecting of an anti-inflammatory phytotherapy for use during pregnancy.

ETHNOPHARMACOLOGICAL RELEVANCE Gochnatia polymorpha ssp. floccosa is used in folk medicine to treat inflammation and infections. Non-steroidal anti-inflammatory drugs (NSAIDs) are the most commonly consumed medications during pregnancy in women with inflammatory diseases. However, the relationship between the use of NSAIDs and the risk of miscarriage and birth defects and/or benefits is not fully understood. Thus, an investigation regarding the use of Gochnatia polymorpha during gestation is of relevance for developing safe anti-inflammatory drugs for use during pregnancy. MATERIALS AND METHODS The pregnant females were randomly divided into 5 groups. Control group received a hydroalcoholic solution (1.2%), via gavage, for at least 15 days prior to mating and throughout the gestational period. The pre-treatment group received Gochnatia polymorpha ethanol extract (GPEE), via gavage, at a dose of 100mg/kg body weight (b.w.) for at least 15 days prior to mating and up to the appearance of the vaginal plug. The organogenesis group received GPEE at a dose of 100mg/kg (b.w.), via gavage, on the 5-15th gestacional day. The pregnancy group received GPEE at a dose of 100mg/kg (b.w.), via gavage, throughout the gestational period (from the 1st to the 18th day of pregnancy). The pre+pregnancy group received GPEE at a dose of 100mg/kg (b.w.), via gavage, for at least 15 days prior to mating and throughout the entire gestational period. The clinical signals of maternal toxicity and teratogenesis were evaluated. Additional assays to evaluate chronic inflammation, antigenotoxicity and immunomodolatory activity were performed. RESULTS AND CONCLUSIONS The results indicated that GPEE does not interfere with reproductive performance or embryo-fetal development but does correlate with reduced weight and fetal length. The extract was not teratogenic or mutagenic or an immunomodulator. However, GPEE did exhibit effective anti-inflammatory activity. Based on this study, it can be inferred that GPEE is an important, safe anti-inflammatory agent for use during pregnancy according to the experimental design we utilized, which opens up possibilities for the bioprospecting of a new anti-inflammatory phytotherapy for use during pregnancy.