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Erratum in - Corrigendum: Vitamin D3 as adjuvant in the treatment of type 2 diabetes mellitus: modulation of genomic and biochemical instability. Fagundes GE, Macan TP, Rohr P, Damiani AP, Da Rocha FR, Pereira M, Longaretti LM, Vilela TC, Ceretta LB, Mendes C, Silveira PCL, Teixeira JPF, de Andrade VM. Mutagenesis. 2019 May 29;34(2):215. doi: 10.1093/mutage/gez006. Type 2 diabetes mellitus has undergone a worldwide growth in incidence in the world and has now acquired epidemic status. There is a strong link between type 2 diabetes and vitamin D deficiency. Because vitamin D has beneficial effects on glucose homeostasis, the aim of this study was to evaluate the influence of vitamin D3 supplementation on the modulation of glycaemic control and other metabolic effects, as well as modulation of genomic instability in patients with type 2 diabetes. We evaluated 75 patients with type 2 diabetes, registered in the Integrated Clinics of the University of Southern Santa Catarina. Participants received 4000 IU of vitamin D3 (25(OH)D) supplementation daily for 8 weeks. Blood samples were collected at the beginning and at the end of the supplementation, and 4 weeks after the end of supplementation. The glycidic and lipid profiles [total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein and triglycerides], oxidative stress, DNA damage and 25(OH)D levels were evaluated. Vitamin D3 supplementation for 8 weeks showed enough to significantly increase blood levels of 25(OH)D. A significant difference in lipid profile was observed only in non-HDL cholesterol. Significant changes were observed in glucose homeostasis (fasting glucose and serum insulin) and, in addition, a reduction in the parameters of oxidative stress and DNA damage. There was a significant reduction in the values of 25(OH)D 4 weeks after the end of the supplementation, but levels still remained above baseline. Use of vitamin D supplementation can be an ally in the health modulation of patients with type 2 diabetes mellitus This work was supported by grants from Conselho Nacional de Pesquisa e Desenvolvimento (CNPq), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Fundação de Amparo à Pesquisa e Inovação do Estado de Santa Catarina (FAPESC) and Programa de Pós-Graduação em Ciências da Saúde/ Universidade do Extremo Sul Catarinense. info:eu-repo/semantics/publishedVersion

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.

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.

Mutations in the tyrosine aminotransferase gene have been identified to cause tyrosinemia type II which is inherited in an autosomal recessive manner. Studies have demonstrated that an excessive production of ROS can lead to reactions with macromolecules, such as DNA, lipids, and proteins. Considering that the L-tyrosine may promote oxidative stress, the main objective of this study was to investigate the in vivo effects of L-tyrosine on DNA damage determined by the alkaline comet assay, in brain and blood of rats. In our acute protocol, Wistar rats (30 days old) were killed 1 h after a single intraperitoneal L-tyrosine injection (500 mg/kg) or saline. For chronic administration, the animals received two subcutaneous injections of L-tyrosine (500 mg/kg, 12-h intervals) or saline administered for 24 days starting at postnatal day (PD) 7 (last injection at PD 31), 12 h after the last injection, the animals were killed by decapitation. We observed that acute administration of L-tyrosine increased DNA damage frequency and damage index in cerebral cortex and blood when compared to control group. Moreover, we observed that chronic administration of L-tyrosine increased DNA damage frequency and damage index in hippocampus, striatum, cerebral cortex and blood when compared to control group. In conclusion, the present work demonstrated that DNA damage can be encountered in brain from animal models of hypertyrosinemia, DNA alterations may represent a further means to explain neurological dysfunction in this inherited metabolic disorder and to reinforce the role of oxidative stress in the pathophysiology of tyrosinemia type II.

Silver nanoparticles (Ag-NPs) are the most prominent nanoproducts. Due to their antimicrobial activity, they have been incorporated in different materials, such as catheters, clothes, electric home appliance, and many others. The genotoxicity of Ag-NPs (5–45 nm), in different concentrations and times of exposure, was evaluated by the comet assay in in vitro and in vivo conditions, respectively, using human peripheral blood and Swiss mice. The results showed the genotoxic effect of Ag-NPs in vitro, in all the doses tested in the initial hour of exposure, possibly through the reactive oxygen species generation. Nevertheless, the values for this damage decrease with time, indicating that the DNA may have been restored by the repair system. In the in vivo conditions, we found no genotoxicity of Ag-NPs in any hour of exposure and any dose investigated, which can be attributed to the activation of a cellular antioxidant network and the hydrophobic nature of Ag-NPs. Now, it is absolutely necessary to investigate the role of Ag-NPs in different cell lines in vivo.