Effect of green juice and their bioactive compounds on genotoxicity induced by alkylating agents in mice.

Kale juice (Brassica oleracea L. var. acephala D.C.) is a reliable source of dietary carotenoids and typically contains the highest concentrations of lutein (LT) and beta-carotene (BC) among green leafy vegetables. As a result of their antioxidant properties, dietary carotenoids are postulated to decrease the risk of disease occurrence, particularly certain cancers. The present study aimed to (1) examine the genotoxic and antigenotoxic activity of natural and commercially available juices derived from Brassica oleracea and (2) assess influence of LT or BC against DNA damage induced by alkylating agents such as methyl methanesulfonate (MS) or cyclophosphamide (CP) in vivo in mice. Male Swiss mice were divided into groups of 6 animals, which were treated with water, natural, or commercial Brassica oleraceae juices (kale), LT, BC, MMS, or CP. After treatment, DNA damage was determined in peripheral blood lymphocytes using the comet assay. Results demonstrated that none of the Brassica oleraceae juices or carotenoids produced genotoxic effects. In all examined cell types, kale juices or carotenoids inhibited DNA damage induced by MMS or CP administered either pre- or posttreatment by 50 and 20%, respectively. Under our experimental conditions, kale leaf juices alone exerted no marked genotoxic or clastogenic effects. However, a significant decrease in DNA damage induced by MMS or CP was noted. This effect was most pronounced in groups that received juices, rather than carotenoids, suggesting that the synergy among constituents present in the food matrix may be more beneficial than the action of single compounds. Data suggest that the antigenotoxic properties of kale juices may be of therapeutic importance.

Anesthetic Ketamine-Induced DNA Damage in Different Cell Types In Vivo.

The use of a combination of ketamine and xylazine is broadly used either for anesthesia or euthanasia in rodent animal models in research. However, the genotoxicity and mutagenic effects of these drugs are unknown. Therefore, the aim of this study was to evaluate these effects to help the understanding of elevated values in negative controls in genotoxic/mutagenic assays. Sixty CF-1 mice were divided into ten groups of six mice per group: negative control (saline), positive control (doxorubicin, 40 mg/kg), ketamine at 80 mg/kg and xylazine at 10 mg/kg, ketamine at 100 mg/kg and xylazine at 10 mg/kg, ketamine at 140 mg/kg and xylazine at 8 mg/kg, ketamine at 80 mg/kg, ketamine at 100 mg/kg, ketamine at 140 mg/kg, xylazine at 8 mg/kg, and xylazine at 10 mg/kg. After drug induction, the blood cells were analyzed at 1, 12, and 24 h by the comet assay, while the brain cortex, liver, and kidney cells were verified just at 24 h by the comet assay and bone marrow was tested at 24 h by micronucleus test. The positive control was significantly different in relation to the negative control in all times and tissue analyzed. The dose of ketamine at 140 mg/kg plus xylazine at 8 mg/kg and only ketamine at 140 mg/kg exhibited a genotoxic effect in blood and brain cells at all the times analyzed. The doses of ketamine at 80 and 100 mg/kg in association or not with xylazine showed increased DNA damage at 1 and 12 h, but this effect was reversed after 24 h of drug administration. The liver, kidney, and bone marrow cells of animals treated with ketamine or xylazine isolated or combined did not differ when compared with the negative control. Then, our findings emphasize the necessity of more studies that prove safety of the ketamine use, since that anesthetic can be able to induce false-negative results in genotoxic experimental studies.