Effects of lutein and chlorophyll b on GSH depletion and DNA damage induced by cisplatin in vivo

Recent studies have proposed the use of low concentrations of phytochemicals and combinations of phytochemicals in chemoprevention to reduce cytotoxicity and simulate normal ingestion through diet. The purpose of the present study was to evaluate whether the DNA damage, chromosome instability, and oxidative stress induced by cisplatin (cDDP) are modulated by a combination of the natural pigments lutein (LT) and chlorophyll b (CLb). The protective effects observed for synergism between phytochemicals have not been completely investigated. The comet assay and micronucleus test were performed and the catalase activities and glutathione (GSH) concentrations were measured in the peripheral blood, bone marrow, liver, and kidney cells of mice. The comet assay and micronucleus test results revealed that the pigments LT and CLb were not genotoxic or mutagenic and that the pigments presented antigenotoxic and antimutagenic effects in the different cell types evaluated. This protective effect is likely related to antioxidant properties in peripheral blood cells through the prevention of cDDP-induced GSH depletion. Altogether our results show that the combination of LT and CLb, which are both usually present in the same foods, such as leafy green vegetables, can be used safely.32882883

The effects of oral glutamine on cisplatin-induced nephrotoxicity in rats

The antioxidant activity of the amino acid glutamine was investigated to obtain protection against peroxidative damage in rat kidney and nephrotoxicity induced by the treatment with a single dose of the antitumoral cisplatin (5 mg kg(-1) body weight). The animals were divided into four treatment and control groups of six rats each (n = 6). Cisplatin was injected i.p. and glutamine (300 mg kg(-1) body weight) was given by gavage 24 h before the cisplatin injection. After 24 h and 7 days of cisplatin administration, the rats were sacrificed. A single dose of cisplatin resulted in significant reduction in body weight and creatinine clearance, and higher urinary volumes were observed in all groups treated with this antitumor drug (P < 0.05). Renal tissue from cisplatin-treated rats showed an increase in malondialdehyde production and increase in glutathione contents 24 h and 7 days after cisplatin administration. Pretreatment of rats with glutamine substantially inhibited the increase in the levels of renal glutathione induced by cisplatin 24 h after the i.p. injection. The malondialdehyde, in the renal tissues was significantly reduced 7 days after cisplatin treatment. However, the reduction in the peroxidative damage did not reach the value of the control group. The protective effects obtained by glutamine pretreatment in peroxidative alterations were not observed in the other parameters studied. These results suggest that glutamine partially protect against cisplatin-induced lipid peroxidation damage, but it was not enough to inhibit cisplatin-induced nephrotoxicity in rats. (C) 2003 Elsevier B.V. Ltd. All rights reserved

The effects of oral glutamine on cisplatin-induced genotoxicity in Wistar rat bone marrow cells

Several studies have suggested that dietary supplementation with antioxidants can influence the response to chemotherapy as well as the development of adverse side effects that result from treatment with antineoplastic agents. The emphasis of the present study was to investigate whether the administration of a single dose of oral glutamine had any protective effect against cisplatin-induced clastogenicity. Cisplatin was administered to Wistar rats either alone or after treatment with glutamine. The rats were treated with glutamine (300 mg/kg b.w.) by gavage 24 h before the administration of cisplatin (5 mg/kg b.w., i.p.) and then sacrificed 24h after treatment with cisplatin. Glutamine significantly reduced (by about 48%) the clastogenicity of cisplatin in rat bone marrow cells. The antioxidant action of glutamine presumably modulates the clastogenic action of cisplatin. (C) 2002 Elsevier B.V. B.V. All rights reserved

In Vivo Genotoxicity and Oxidative Stress Evaluation of an Ethanolic Extract from Piquia (Caryocar villosum) Pulp

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)In this study, the ethanolic extract obtained from piquia pulp was assessed for genotoxicity and oxidative stress by employing the micronucleus test in bone marrow and peripheral blood cells in addition to comet, thiobarbituric-acid-reactive substances (TBARS), and reduced glutathione assays in the liver, kidney, and heart. Additionally, phytochemical analyses were performed to identify and quantify the chemical constituents of the piquia extract. Wistar rats were treated by gavage with an ethanolic extract from piquia pulp (75 mg/kg body weight) for 14 days, and 24 h prior to euthanasia, they received an injection of saline or doxorubicin (15 mg/kg body weight, intraperoneally). The results demonstrated that piquia extract at the tested dose was genotoxic but not mutagenic, and it increased the TBARS levels in the heart. Further studies are required to fully elucidate how the properties of ethanolic extract of piquia pulp can affect human health.o TEXTO COMPLETO DESTE ARTIGO, ESTARÁ DISPONÍVEL À PARTIR DE AGOSTO DE 2015.163268271Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [2009/15692-0, 2005/59552-6

Transcriptome and DNA methylation changes modulated by sulforaphane induce cell cycle arrest, apoptosis, DNA damage, and suppression of proliferation in human liver cancer cells

Abnormal epigenetic alterations are one of the keystones of cancer development. Epigenetic targeting drugs have become a promising and effective cancer therapy strategy. However, due to the high toxicity and unclear mechanisms of action of these drugs, natural compounds that cause epigenetic modulation have also been studied. Sulforaphane (SFN) is a promising bioactive compound for epigenetic targeting therapy. In this study, we investigate the effects of SFN on gene expression and DNA methylation in human hepatocellular carcinoma cells (HepG2). Using high throughput technologies in combination with cell-based assays, we find SFN is a potent anticancer agent, as it induces DNA damage, mitotic spindle abnormalities followed by apoptosis and proliferation inhibition in HepG2 cells. Our results show the upregulation of DNA damage response and cell cycle checkpoint genes. Also, we find the downregulation of cellular pathways frequently overexpressed in human cancer. As expected, SFN exerts epigenetic modulation effects by inhibiting histone deacetylases (HDACs). SFN might affect the activity of oncogenic transcription factors through methylation of its binding sites motifs. Our findings offer insights into SFN chemopreventive molecular effects in HepG2 cells and highlight SFN as a valuable natural approach to cancer therapy for future investigatio

Effects of sulforaphane on the oxidative response, apoptosis, and the transcriptional profile of human stomach mucosa cells in vitro

Oxidative stress is a critical factor in the pathogenesis of several gastrointestinal diseases. Sulforaphane (SFN), a bioactive compound found in cruciferous vegetables, activates the redox-sensitive nuclear erythroid 2-related factor 2 (NRF2). In addition to its protective role, SFN exerts cytotoxic effects on cancer cells. However, there is a lack of information concerning the toxicity of SFN in normal cells. We investigated the effects of SFN on cell viability, antioxidant defenses, and gene expression in human stomach mucosa cells (MNP01). SFN reduced ROS formation and protected the cells against induced oxidative stress but high concentrations increased apoptosis. An intermediate SFN concentration (8 μM) was chosen for RNA sequencing studies. We observed upregulation of genes of the NRF2 (antioxidant) pathway, the DNA damage response, and apoptosis signaling; whereas SFN downregulated cell cycle and DNA repair pathway genes. SFN may be cytoprotective at low concentrations and cytotoxic at high concentrations