Schistosomiasis is a serious health issue in tropical regions, and natural compounds have gained popularity in medical science. This study investigated the potential effects of pumpkin seed oil (PSO) on Biomphalaria [B.] alexandrina snails (Ehrenberg, 1831), Schistosoma [S.] mansoni (Sambon, 1907) miracidium, and cercariae. The chemical composition of PSO was determined using gas chromatography/mass spectrometry. A bioassay was performed to evaluate the effects of PSO on snails, miracidia, and cercariae. The results showed no significant mortality of B. alexandrina snails after exposure to PSO, but it caused morphological changes in their hemocytes at 1.0 mg/ml for 24 hours. PSO exhibited larvicidal activity against miracidia after 2 hours of exposure at a LC50 of 618.4 ppm. A significant increase in the mortality rate of miracidia was observed in a dose- and time-dependent manner, reaching a 100% death rate after 10 minutes at LC90 and 15 minutes at LC50 concentration. PSO also showed effective cercaricidal activity after 2 hours of exposure at a LC50 of 290.5 ppm. Histological examination revealed multiple pathological changes in the digestive and hermaphrodite glands. The PSO had genotoxic effects on snails, which exhibited a significant increase [p≤0.05] in comet parameters compared to the control. The findings suggest that PSO has potential as a molluscicide, miracidicide, and cercaricide, making it a possible alternative to traditional molluscicides in controlling schistosomiasis.

Epidemiological evidence shows that regular consumption of Brassicaceae is associated with a reduced risk of cancer and heart disease. Cruciferous species are usually processed before eating and the real impact of cooking practices on their bioactive properties is not fully understood. We have evaluated the effect of common cooking practices (boiling, microwaving, and steaming) on the biological activities of broccoli, cauliflower and Brussels sprouts. Anti-proliferative and chemoprotective effects towards DNA oxidative damage of fresh and cooked vegetable extracts were evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium and Comet assays on HT-29 human colon carcinoma cells. The fresh vegetable extracts showed the highest anti-proliferative and antioxidant activities on HT-29 cells (broccoli>cauliflower = Brussels sprouts). No genotoxic activity was detected in any of the samples tested. The cooking methods that were applied influenced the anti-proliferative activity of Brassica extracts but did not alter considerably the antioxidant activity presented by the raw vegetables. Raw, microwaved, boiled (except broccoli) and steamed vegetable extracts, at different concentrations, presented a protective antioxidative action comparable with vitamin C (1 mm). These data provide new insight into the influence of domestic treatment on the quality of food, which could support the recent epidemiological studies suggesting that consumption of cruciferous vegetables, mainly cooked, may be related to a reduced risk of developing cancer.

Green tea is rich in polyphenolic antioxidants and has widely reported but largely unsubstantiated health benefits. In the present study, genoprotective effects of two types of green tea were studied both in an in vitro and in a human supplementation trial. For the in vitro study, human lymphocytes were pre-incubated in tea (0·005–0·1 %, w/v), washed and subjected to oxidant challenge induced by H2O2. In a placebo-controlled, cross-over supplementation study, eighteen healthy volunteers took 2 × 150 ml/d of 1 % (w/v) green tea (‘Longjing’ green tea or ‘screw-shaped’ green tea) or water (control) for 4 weeks (n 6). Subjects took all the three treatments in a random order, with 6 weeks' washout between each treatment. Fasting blood and urine were collected before and after each treatment. The comet assay was used to measure the resistance of lymphocytic DNA to H2O2-induced challenge. Basal oxidation-induced DNA damage was measured using the formamidopyrimidine glycosylase (Fpg) enzyme-assisted comet assay. Urine 7,8-dihydro-2-deoxyguanosine (8-oxodG, mol/mmol creatinine), a biomarker of whole-body oxidative stress, was measured by liquid chromatography with tandem MS. In vitro testing results of tea-treated cells showed increased (P < 0·05) resistance of DNA to the challenge. In the supplementation trial, a significant (P < 0·05) increase in resistance was also observed. Furthermore, the FPg comet data showed >20 % decrease in DNA damage with tea supplementation: mean and standard deviation changes in %DNA in comet tail in the Fpg-assisted comet assay were: − 5·96 (sd 3·83) % after Longjing tea; − 6·22 (sd 3·34) % after screw-shaped tea; +0·91 (sd 5·79) % after water (P < 0·05). No significant changes in urine 8-oxodG were seen. The results indicate that green tea has significant genoprotective effects and provide evidence for green tea as a ‘functional food’.

Polycyclic aromatic hydrocarbons (PAH) are procarcinogens that can be commonly found in our food and environment. Upon biotransformation in our body system, they can cause DNA damage through the generation of genotoxic species and oxidative stress. Phase I and II enzymes are pivotal in the process of proximate carcinogen formation and elimination. Some dietary phytochemicals are strong inhibitors to the phase I enzymes. In the present study, we investigated the effect of the red wine compound resveratrol on DNA damage induced by PAH in a non-tumorigenic breast cell line MCF-10A. Resveratrol ranging from 1 to 5 μm could significantly suppress the expressions of cytochrome P450 (CYP) 1A1, CYP1B1 and UDP-glucuronosyltransferase (UGT) 1A1 induced by 7,12-dimethylbenz[a]anthracene (DMBA). The comet assay indicated that DMBA introduced DNA damage to these cells, and co-treatment of resveratrol at 5 or 10 μm could alleviate the damage. Further investigation illustrated that resveratrol reduced the binding of DMBA metabolites to DNA with no effect on DMBA-induced oxidative DNA damage. Since the phase II enzyme UGT1A1 was suppressed, the elimination of DMBA metabolites would not have contributed to the reduction in the DMBA metabolite–DNA binding. In summary, resveratrol might protect breast cells against PAH-induced DNA damage. The underlying mechanism was mediated by phase I enzyme suppression rather than phase II enzyme induction or oxidative DNA repair.

The effect of different activation protocols on DNA integrity of porcine oocytes matured in vitro was analysed using the comet assay. The oocytes from ovaries of slaughtered gilts were cultured for 48 h in modified M199 medium. They were then freed of cumulus cells and treated continuously or intermittently with a nitric oxide (NO) donor for 6 h. Standard activation with calcium ions (Ca2+) and culture without any treatment served as positive and negative controls, respectively. The activation was assessed according to the formation of pronuclei. Exposure of oocytes to Ca2+ was associated with high activation efficiency, but decreased DNA integrity. The opposite, i.e. low activation efficiency but high DNA integrity was observed after continuous exposure to NO. Intermittent action of NO increased the activation rate, while the values of DNA damage remained at low levels. Our data suggest that an increased DNA instability could be the main reason compromising the further embryonic development of oocytes activated by the standard protocol. The intermittent treatment with NO thus represents a promising step to optimization of parthenogenetic activation of pig oocytes.

Berry seeds are a tocopherol-rich by-product of fruit processing without specific commercial value. In a human intervention study, the physiological impact of blackcurrant seed press residue (PR) was tested. Thirty-six women (aged 24 ± 3 years; twenty non-smokers, sixteen smokers) consumed 250 g bread/d containing 8 % PR for a period of 4 weeks (period 3). Comparatively, a control bread without PR (250 g/d) was tested (period 2) and baseline data were obtained (period 1). Blood, stool and 24 h urine were collected during a 5 d standardised diet within each period. Tocopherol and Fe intakes were calculated from food intake. In serum, tocopherol concentration and Fe parameters were determined. In urine, oxidative stress markers 8-oxo-2′-deoxyguanosine, 8-iso-PGF2α and inflammatory response marker 15-keto-dihydro-PGF2α were analysed. Stool tocopherol concentration, genotoxicity of faecal water (comet assay) and antioxidant capacity of stool (aromatic hydroxylation of salicylic acid) were determined. Fe and total tocopherol intake, total tocopherol concentrations in serum and stool, and genotoxicity of faecal water increased with PR bread consumption (P < 0·05). The antioxidant capacity of stool decreased between baseline and intervention, expressed by increased formation of 2,3- and 2,5-dihydroxybenzoic acid in vitro (P < 0·05). In smokers, 8-oxo-2′-deoxyguanosine increased with PR consumption (P < 0·05). Prostane concentrations were unaffected by PR bread consumption. In summary, the intake of bread containing blackcurrant PR for 4 weeks increased serum and stool total tocopherol concentrations. However, various biomarkers indicated increased oxidative stress, suggesting that consumption of ground berry seed may not be of advantage.

Anthocyanins are a class of flavonoids, widely spread throughout the plant kingdom, exhibiting important antioxidant and anti-inflammatory actions as well as chemotherapeutic effects; nonetheless, little is known about the molecular mechanisms by which these activities are exerted. The present study is aimed at investigating molecular mechanisms involved in the chemotherapeutic effects induced by both cyanidin-3-O-β glucopyranoside (CY3G) and its aglycon form, cyanidin chloride (CY), in human colon cancer cells (CaCo2). The effect on cell growth, reactive oxygen species (ROS) formation and cell cycle/stress proteins modification, including ataxia teleangectasia mutated protein (ATM), p53, p21, 8-oxoguanine DNA glycosylase (OGG1), 70 kDa heat shock protein (HSP70) and topoisomerase IIβ, as well as on DNA fragmentation, was determined. CY and CY3G treatment affect cell growth and cell proliferation, this latter in a moderately dose-dependent way. Interestingly, ROS level is decreased by any concentration of CY and, only at the lowest concentration, by CY3G. Moreover, the two molecules exert their activities increasing ATM, topoisomerase II, HSP70 and p53 expression. The analysis of DNA fragmentation by Comet assay evidences: (1) a dose-dependent increase in DNA damage only after treatment with CY3G; (2) a more evident trend in the DNA fragmentation when the treatment is performed on agarose embedded cells (cellular atypical Comet); (3) a highly dose-dependent DNA fragmentation induced by CY when the treatment is carried out on agarose embedded naked DNA (acellular atypical Comet). The present findings substantiate a possible chemotherapeutic role of anthocyanins and suggest that CY and CY3G act on CaCo2 by different mechanisms, respectively, ROS-dependent and ROS-independent.

Polycyclic aromatic hydrocarbons (PAH) are established cancer initiators that can be found in our food and environment. Some dietary phytochemicals are strong inhibitors of PAH-induced mutagenesis. The soya isoflavone genistein has been shown previously in our laboratory to be an inhibitor of PAH metabolite binding to DNA. In the present study, we investigated the effect of genistein on oxidative DNA damage induced by PAH in the non-tumorigenic breast cell line MCF10A. 7,12-Dimethyl-benz[a]anthracene (DMBA) can induce expressions of CYP1A1 and CYP1B1 which are known to be responsive to PAH. These enzymes, in turn, will metabolise the PAH into their ultimate carcinogenic forms. Genistein can significantly suppress the expressions within 5 μm. The comet assay indicated that DMBA introduced DNA damage to these cells, and co-treatment with genistein at 5 or 10 μm could alleviate the damage. In addition to the chelation of DMBA metabolites to DNA, flow cytometry results revealed that oxidation was also a factor of DNA damage. The oxidative DNA damage could be removed by co-treating with 10 μm-genistein. Because no increased oxidative DNA repair was observed, suppression on the cytochrome enzymes appeared to be the underlying mechanism.

We previously developed an in vitro-production system for porcine embryos and reported that the addition of glutamine (Gln) and hypotaurine (HT) during in vitro culture improved embryo development. This study examined the effects of Gln and HT on in vitro development, intracellular oxidative status and DNA damage of porcine preimplantation embryos. Porcine zygotes produced by in vitro maturation (IVM) and in vitro fertilization (IVF) were cultured until day 2 (day 0 = day of IVF) in porcine zygote medium (PZM) including 2 mM Gln and 5 mM HT, namely PZM-5. On day 2, the cleaved embryos were selected and cultured for 24 h in PZM-5 to which one of the following substances was added: (1) none (control); (2) Gln; (3) HT; or (4) Gln + HT. After 24 h of culture in each medium, the embryos were then returned to PZM-5 and cultured until day 5. Day-5 blastocyst yield was significantly higher in the Gln and Gln + HT groups (p < 0.05) than in the control and HT groups. In addition, Gln + HT significantly increased the total number of cells in blastocysts (p < 0.05) compared with the control. Although the number of cells and the intracellular GSH levels in day-3 cleaved embryos did not differ among treatments, addition of Gln, HT or Gln + HT significantly (p < 0.05) reduced the intracellular H2O2 content and the extent of DNA damage compared with the control. These results indicate that the presence of Gln and HT in PZM-5 from day 2 to day 3 promotes the development of porcine embryos by improvement of intracellular oxidative status.

Experimental evidence suggests that most herbs and spices possess a wide range of biological and pharmacological activities that may protect tissues against O2-induced damage. The objectives of the present study were: first, to determine the effects of plant extracts on the viability, membrane integrity, antioxidant status and DNA integrity of Caco-2 cells and second, to investigate the cytoprotective and genoprotective effects of these plant extracts against oxidative stress in Caco-2 cells. The plant extracts examined were rosemary (Rosmarinus officinalis L.), oregano (Origanum vulgare L.), sage (Salvia officinalis L.) and echinacea (Echinacea purpurea L.). Cell membrane integrity was assessed by the lactate dehydrogenase release assay. Viability was determined by the neutral red uptake assay (NRUA) and the concentration of compound that resulted in 50 % cell death (IC50) was calculated. Antioxidant status of the cells was assessed by measuring GSH content, catalase activity and superoxide dismutase activity. To examine their cytoprotective and genoprotective effects, Caco-2 cells were pre-treated with each plant extract for 24 h followed by exposure to H2O2. DNA damage was assessed by the comet assay and cell injury was determined by the NRUA. Rosemary was the most toxic (IC50 123 μg/ml) and echinacea the least toxic (IC50 1421 μg/ml). Sage was the only plant extract to affect the antioxidant status of the cells by increasing GSH content. Sage, oregano and rosemary protected against H2O2-induced DNA damage (olive tail moment and percentage tail DNA), whereas protection against H2O2-induced cytotoxicity was afforded by sage only.

The transfer of polycyclic aromatic hydrocarbons (PAHs) from bivalves, through the food chain to vertebrates was of concern. Our research aimed at estimating potential effects for consumers resulting from the ingestion of seafood contaminated by oil spill pollutants.After the “Erika” wreck, mussels (Mytilus sp.) were collected from sites of the Atlantic coast impacted to various degrees by the oil slick and constituted contaminated food for rats during 2 and 4 weeks. Genotoxic damage were studied in rats by means of COMET assay carried out in liver, bone marrow and peripheral blood. Biochemical and genomic effects such as the induction of CYP 1A1 and the expression of cytochrome genes were measured in rat livers. The most sensitive biological parameter reflecting the transfer of contaminants via the food appeared to be DNA breaks studied by means of the COMET assay. Genotoxic damage, observed mainly in the liver, were rather moderate and remained not persistent. This study underlined the bioavailability of pollutants in fuel oil contaminated mussels for consumers, and the complexity of the contamination consecutive to the oil spill. The occurrence of related PAH compounds in addition to non-substituted PAHs in fuel oils and mussels raised the question of their implication in the registered effects.

Probiotics reduce the risk of colon cancer by inhibiting carcinogen-induced DNA damage in animals, but there are no analogous data in human subjects. To enhance knowledge of the effects of probiotics in human subjects, we have investigated the genotoxicity of faecal water after dietary intervention with standard yoghurt or with probiotic yoghurt, which included the strains Lactobacillus acidophilus 145 and Bifidobacterium longum 913. Faeces were collected from nine healthy volunteers after intervention with probiotic yoghurt or standard yoghurt. Faecal water was isolated and incubated with human colon tumour cells HT29clone19A. DNA strand breaks, oxidised DNA bases and damage after challenge with H2O2 were determined by micro-gel-electrophoresis. Faecal water was genotoxic in comparison with NaCl, but protected against H2O2-induced DNA strand breaks. The intervention with probiotic yoghurt significantly lowered faecal water genotoxicity compared with standard yoghurt. However, probiotic intervention also increased oxidative damage; this either reflected prooxidative activity or stimulation of endogenous defence systems. Altogether, the balance of effects favoured protection, since faecal water from the probiotic group reduced overall genetic damage. Thus, there was a reduction of strand break-inducing compounds in human faeces after dietary intervention with probiotic bacteria. This protection reflected results from previous studies in carcinogen-exposed animals where probiotics reduced DNA damage in colon cells.

This study examines the effects of Taenia crassiceps cysticerci on the viability of a human T lymphocyte cell line (Jurkat). Both budding and non-budding T. crassiceps metacestodes were cultured over 24 and 48 h in the presence of Jurkat cells. Cell viability decreased with increasing numbers of cysticerci, particularly budding cysticerci. Single cell gel electrophoresis (comet) analysis, which grades DNA damage, showed a significant increase in apoptosis at 24 and 48 h. The morphology of treated cells was determined using acridine orange with the classical morphology of apoptotic bodies seen to increase with increasing cysticerci numbers over time. These results indicate that parasite-induced apoptosis occurs during murine cysticercosis. Such a mechanism may be important in survival of other metacestode infections of medical or veterinary importance.