Selenium nanoparticles (SeNPs) are worthy of attention and development for nutritional supplementation due to their health benefits in both animals and humans with low toxicity, improved bioavailability, and controlled release, being greater than the Se inorganic and organic forms. Our previous study reported that Anoectochilus burmannicus extract (ABE)-synthesized SeNPs (ABE-SeNPs) exerted antioxidant and anti-inflammatory activities. Furthermore, ABE could stabilize and preserve the biological activities of SeNPs. To promote the ABE-SeNPs as supplementary and functional foods, it was necessary to carry out a safety assessment. Cytotoxicity testing showed that SeNPs and ABE-SeNPs were harmless with no killing effect on Caco2 (intestinal epithelial cells), MRC-5 (lung fibroblasts), HEK293 (kidney cells), LX-2 (hepatic stellate cells), and 3T3-L1 (adipocytes), and were not toxic to isolated human PBMCs and RBCs. Genotoxicity assessments found that SeNPs and ABE-SeNPs did not induce mutations in Salmonella typhimurium TA98 and TA100 (Ames test) as well as in Drosophila melanogaster (somatic mutation and recombination test). Noticeably, ABE-SeNPs inhibited mutation in TA98 and TA100 induced by AF-2, and in Drosophila induced by urethane, ethyl methanesulfonate, and mitomycin c, suggesting their anti-mutagenicity ability. This study provides data that support the safety and anti-genotoxicity properties of ABE-SeNPs for the further development of SeNPs-based food supplements.

Zearalenone (ZEN) is a non-steroidal mycoestrogen produced by the Fusarium genus. ZEN and its metabolites compete with 17-beta estradiol for cytosolic estrogen receptors, causing reproductive alterations in vertebrates. ZEN has also been associated with toxic and genotoxic effects, as well as an increased risk for endometrial adenocarcinomas or hyperplasia, breast cancer, and oxidative damage, although the underlying mechanisms remain unclear. Previous studies have monitored cellular processes through levels of transcripts associated with Phase I Xenobiotic Metabolism (Cyp6g1 and Cyp6a2), oxidative stress (hsp60 and hsp70), apoptosis (hid, grim, and reaper), and DNA damage genes (Dmp53). In this study, we evaluated the survival and genotoxicity of ZEN, as well as its effects on emergence rate and fecundity in Drosophila melanogaster. Additionally, we determined levels of reactive oxygen species (ROS) using the D. melanogaster flare and Oregon R(R)-flare strains, which differ in levels of Cyp450 gene expression. Our results showed that ZEN toxicity did not increase mortality by more than 30%. We tested three ZEN concentrations (100, 200, and 400 μM) and found that none of the concentrations were genotoxic but were cytotoxic. Taking into account that it has previously been demonstrated that ZEN administration increased hsp60 expression levels and apoptosis gene transcripts in both strains, the data agree with an increase in ROS and development and fecundity alterations. Since Drosophila lacks homologous genes for mammalian estrogen receptors alpha and beta, the effects of this mycotoxin can be explained by a mechanism different from estrogenic activity.

The consumption of a nutritious diet including phytochemicals can minimize mutations as the primary cause of carcinogenesis. Bean consumption supplies calories, minerals and phytochemicals but their anti-mutagenic properties in vivo remain little understood. Hence, the present study aimed to study the mutagenicity and anti-mutagenic properties of five bean milks using the somatic mutation and recombination test (SMART) involving Drosophila with high bioactivation. Milk derived from five bean varieties, namely black bean (Phaseolus vulgaris), red kidney bean (Phaseolus vulgaris), mung bean (Phaseolus aureus), peanut (Arachis hypogaea) and soybean (Glycine max) did not induce DNA mutations in Drosophila with high bioactivation, indicating their genome-safe properties. All bean milks showed anti-mutagenicity against the food-derived mutagen, urethane, in vivo with different degrees of inhibition. In the co-administration study, larvae were treated with each bean milk together with urethane. Soybean milk showed the highest anti-mutagenicity at 27.75%; peanut milk exhibited the lowest at 7.51%. In the pre-feeding study, the larvae received each bean milk followed by urethane. Soybean milk exhibited the highest anti-mutagenic potential, followed by red kidney bean and black bean milks. Total phenolic and antioxidant data revealed that the anti-mutagenicity of both red kidney bean milk and black bean milk might be derived from their phenolic or antioxidant properties; other phytochemicals may contribute to the high anti-mutagenicity observed in soybean milk. Further investigations on the anti-mutagenicity of bean milks against other dietary mutagens are required to develop bean-based products with potent anti-mutagenic properties.

Genomic instability, one of cancer\'s hallmarks, is induced by genotoxins from endogenous and exogenous sources, including reactive oxygen species (ROS), diet, and environmental pollutants. A sensitive in vivo genotoxicity test is required for the identification of human hazards to reduce the potential health risk. The somatic mutation and recombination test (SMART) or wing spot test is a genotoxicity assay involving Drosophila melanogaster (fruit fly) as a classical, alternative human model. This review describes the principle of the SMART assay in conjunction with its advantages and disadvantages and discusses applications of the assay covering all segments of health-related industries, including food, dietary supplements, drug industries, pesticides, and herbicides, as well as nanoparticles. Chemopreventive strategies are outlined as a global health trend for the anti-genotoxicity of interesting herbal extract compounds determined by SMART assay. The successful application of Drosophila for high-throughput screening of mutagens is also discussed as a future perspective.

Thallium (Tl) is a heavy and toxic metal and a byproduct of several human activities, such as cement production, mining, and coal combustion. Thallium is found in fruits, vegetables, and animal fodder with high Tl contamination; therefore, it is an environmental pollution issue and a toxicological contamination problem for human beings and other organisms when exposed to it. The mutagenic potential of Tl and its compounds is controversial, and there are few in vivo studies on its effects. We conducted the animal bioassay Drosophila wing somatic mutation and recombination test (SMART) to test for genotoxicity and assessed the genotoxic effects of Tl acetate (TlCH3COO) and Tl sulfate (Tl2SO4) on Drosophila melanogaster. Third instar larvae from the SMART standard cross (ST) were fed Tl acetate [0.2, 2, 20, 200, 600 and 1200 μM] and Tl sulfate [0.2, 2, 20, 200, and 600 μM]. Hexavalent chromium [CrO3, 500 μM] served as the positive control, and Milli-Q water served as the negative control. Only the high Tl2SO4 [600 μM] concentration resulted in genotoxicity with 87.6% somatic recombination, and both salts disrupted cell division of wing imaginal disc cells, showing the expected cytotoxic effects. Genotoxic risks due to high metal levels by bioaccumulation of Tl+1 or its compounds require further evaluation with other in vivo and in vitro assays.

This study investigates Bisphenol A (BPA) induced oxidative stress that mediates the genotoxicity in in vivo model Drosophila melanogaster. The calculated LC50 for BPA was 12.35 μg/mL. The strains of D. melanogaster were reared in 0.1, 1.0, 2.5 and 5.0 μg/mL BPA treated food media from the embryonic stage (egg); oxidative stress and genotoxicity parameters were analyzed. Food intake analysis confirmed that BPA is not an anti feedant for Drosophila larvae and it consumed BPA containing food. Increased reactive oxygen species (ROS) and lipid peroxidation (LPO) and depletion of superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and glutathione-s-transferase (GST) antioxidant activities were observed in BPA treated groups compared to control. Positive single spots/wing frequencies were observed in standard (ST) and high bioactivation (HB) crosses of marker heterozygous (MH; mwh/flr3) and balancer heterozygous (BH; mwh/TM3) genotype flies indicating BPA is mutagenic and not recombinogenic. A significant increase in tail length and % tail DNA in Comet assay after BPA treatment reveals that BPA has a potential to induce the genotoxicity. Present study suggests that BPA exposure induces oxidative stress, which could be one of the possible mechanisms for induction of genotoxicity.

The mechanism of lead (Pb) modulated heme synthesis pathway induced oxidative stress mediated genotoxicity using standard (ST) and high bioactivation (HB) crosses of Drosophila melanogaster was addressed in the present study. Third instar larvae derived from the ST or HB crosses were reared in sub lethal concentrations of lead acetate (PbAc) treated food media and showed that Pb was readily taken up and accumulated in the said crosses. Pb modulated heme synthesis was evident by significant reductions of δ-aminolevulinic acid dehydratase (δ-ALA-D) and cytochrome P450 (CYP450) and increased accumulation of δ-aminolevulinic acid (δ-ALA). The results have also demonstrated that Pb induced oxidative stress by overproducing reactive oxygen species (ROS) and lipid peroxidation (LPO) and depletion of the antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and glutathione-s-transferase (GST). Wing somatic mutation and recombination test (SMART) using ST and HB crosses revealed that Pb is mutagenic and weakly recombinogenic. By employing larval hemocytes, there was an increase in percent of tail DNA in alkaline comet compared to that of neutral comet revealing the DNA single strand breaks were the products of Pb modulated heme synthesis pathway induced oxidative free radicals. Based on these findings, it can be concluded that Pb modulated heme synthesis pathway induces oxidative stress that mediates the genotoxicity in D. melanogaster.

Several epidemiological studies have reported the relation between chromium exposure (used in different industrial processes) and cancer risk. Evidence indicates that the hexavalent form is mutagenic and carcinogenic. Chemoprevention has emerged as a good strategy for reducing the risk from exposure to heavy metals. There is evidence that some tetrapyrrols such as protoporphyrin IX (PP-IX), a porphyrin without a metal center and which is a precursor of hemoglobin and cytochrome, acts as an antioxidant modulating the induction of antioxidant enzymes. The present study was performed to evaluate their antimutagenic potential of PP-IX against genetic damage induced by chromium trioxide (CrO3). The wing spot test was used. Groups of 48 h-old larvae were pretreated for 24 h with 0, 0.69, 6.9, or 69 mM of PP-IX, after which groups of larvae were fed 0.025-2.5 mM CrO3 solution in Drosophila instant medium. The results indicated that the lower PP-IX concentration (0.69 mM) significantly reduced the genetic damage induced by all CrO3 concentrations tested. In contrast, 6.9 and 69 mM only inhibited the damage induced by CrO3 2.5 mM. Absence of an inhibitor effect of PP-IX against 20 Gy gamma rays suggested that this porphyrin acted primarily by forming complexes with chromium at low doses, inactivating its genotoxic action rather than capturing or inactivating the reactive oxygen species generated by the chromium.

4-nitroquinoline-1-oxide (4-NQO) is a pro-oxidant carcinogen bioactivated by xenobiotic metabolism (XM). We investigated if antioxidants lycopene [0.45, 0.9, 1.8 μM], resveratrol [11, 43, 172 μM], and vitamin C [5.6 mM] added or not with FeSO4 [0.06 mM], modulate the genotoxicity of 4-NQO [2 mM] with the Drosophila wing spot test standard (ST) and high bioactivation (HB) crosses, with inducible and high levels of cytochromes P450, respectively. The genotoxicity of 4-NQO was higher when dissolved in an ethanol - acetone mixture. The antioxidants did not protect against 4-NQO in any of both crosses. In the ST cross, resveratrol [11 μM], vitamin C and FeSO4 resulted in genotoxicity; the three antioxidants and FeSO4 increased the damage of 4-NQO. In the HB cross, none of the antioxidants, neither FeSO4, were genotoxic. Only resveratrol [172 μM] + 4-NQO increased the genotoxic activity in both crosses. We concluded that the effects of the antioxidants, FeSO4 and the modulation of 4-NQO were the result of the difference of Cyp450s levels, between the ST and HB crosses. We propose that the basal levels of the XM\'s enzymes in the ST cross interacted with a putative pro-oxidant activity of the compounds added to the pro-oxidant effects of 4-NQO.

Bupivacaine and levobupivacaine are amino amide local anesthetics commonly used in medical practice. Although bupivacaine consists of a racemic mixture of S (-)-bupivacaine and R (+)-bupivacaine enantiomers, levobupivacaine is comprised of pure S (-)-bupivacaine. It has been known that levobupivacaine is preferable to bupivacaine since it may cause cardiovascular and nervous system toxicity. For determining genotoxicity of these anesthetics, we used the wing somatic mutation and recombination test in Drosophila melanogaster. Three-day-old trans-heterozygous larvae were treated with bupivacaine and levobupivacaine. Analysis of the standard crosses indicated that bupivacaine and levobupivacaine did not exhibit mutagenic or recombinogenic activity until toxic doses have been reached at the larval stage. When we examined bupivacaine and levobupivacaine in the HB cross, bupivacaine did not exhibit any genotoxicity at high concentrations (500 µg/mL), but levobupivacaine did exert genotoxicity at high concentrations (1000 µg/mL)-depending on the substantial recombinogenic effect.