Human exposure to pollutants has been on the rise. Thus, researchers have been focused on understanding the effect of these compounds on human health, especially on the genetic information by using various tests, among them the somatic mutation and recombination tests (SMARTs). It is a sensitive and accurate method applicable to genotoxicity analysis. Here, a comprehensive bibliometric analysis of SMART assays in genotoxicity studies was performed to assess publication trends of this field. Data were extracted from the Web of Science database and analyzed by the bibliometric tools HistCite, Biblioshiny (RStudio), VOSViewer, and CiteSpace. Results have shown an increase in the last 10 years in terms of publication. A total of 392 records were published in 96 sources mainly from Brazil, Spain, and Turkey. Research collaboration networks between countries and authors were performed. Based on document co-citation, five large research clusters were identified and analyzed. The youngest research frontier emphasized on nanoparticles. With this study, how research trends evolve over years was demonstrated. Thus, international collaboration could be enhanced, and a promising field could be developed.

Hydroxyapatite (HAP) occurs naturally in sedimentary and metamorphic rocks and constitutes the hard structures in many organisms. Since synthetic nano-sized HAP (HAP-NPs) are used in orthopedic applications and for heavy metal remediation in aquatic and terrestrial media, both environment and humans are exposed to them. Due to the concerns about their potential hazards, the genotoxic effects that round/rod forms of HAP-NPs were investigated in Drosophila using the wing-spot and the comet assays. Furthermore, caspase activities were evaluated to examine the activation of cell death pathways. As a novelty, the expression of 36 genes involved in DNA repair was investigated, as a tool to indirectly determine DNA damage induction. Obtained sizes were 35-60 nm (roundHAP-NPs) and 45-90 nm (rodHAP-NPs) with a low Zeta-potential (-1.65 and 0.37 mV, respectively). Genotoxicity was detected in the wing-spot (round form), and in the comet assay (round and rod-like HA-NPs). In addition, increased expression of Caspases 3/7, 8, and 9 activities were observed. For both HAP forms, increased changes in the expression were observed for mismatch repair genes, while decreased expression was observed for genes involved in ATM, ATR, and cell cycle pathways. The observed changes in the repair pathways would reinforce the view that HAP-NPs have genotoxic potential, although more markedly in the round form. Thus, the environmental presence of engineered nanoparticles, including HAPs, raises concerns about potential effects on human health. It is essential that the effects of their use are carefully assessed and monitored to ensure safety and to mitigate any potential adverse effects.

Phytoestrogens are xenoestrogens found in plants with a myriad of health benefits. However, various studies reported the genotoxic effects of these substances. Thus, we reviewed in vitro and in vivo studies published in PubMed, Scopus, and Web of Science to evaluate the genotoxic and the genoprotective potential of phytoestrogens. Only studies written in English and intended to study commercially available phytoestrogens were included. The screening was performed manually. Moreover, the underlying mechanism of action of phytoestrogens was described. Around half of those studies (43%) reported genoprotective results. However, several studies revealed positive results for genotoxicity with specific model organisms and with dose/concentration dependence. The assessment of the selected articles showed substantial differences in the used concentrations and a biphasic response was recorded in some phytoestrogens. As far as we know, this is the first study to assess the genotoxic and genoprotective effects of phytoestrogens systematically.

Research background. Kombucha is a fermented beverage with several health benefits; however, to improve its antioxidant activity, new raw materials such as hop, madimak and hawthorn were included in the present study. Experimental approach. The somatic mutation and recombination test (SMART) was performed on the fruit fly (Drosophila melanogaster) to evaluate the antigenotoxic potential of black tea-flavoured kombucha and three other flavours of kombuchas (hop, madimak and hawthorn) against H2O2- and K2Cr2O7-induced genotoxicity. Furthermore, a lifespan assay was performed to assess the effects of kombuchas on the longevity of the fruit fly. Results and conclusions. According to the results obtained from the SMART assay, hop-flavoured kombucha attenuated genotoxicity induced by H2O2, and madimak-flavoured kombucha reduced genotoxicity induced by H2O2 and K2Cr2O7. Black tea- and hop-flavoured kombucha prolonged the lifespan of the fruit fly (Drosophila melanogaster) after the treatment with H2O2 and K2Cr2O7. Novelty and scientific contribution. Hop-flavoured kombucha is a promising antioxidant that protects the genome and extends the lifespan of the fruit fly. This study sheds light on novel beverages that can combat ageing and protect against genotoxicity.

Biomaterials are engineered products that are widely used in many areas of medicine fields such as orthopaedic applications, facial and maxillofacial surgery, artificial heart parts, metal parts, and implantable devices. These materials are widely used in medicine because they are biocompatible with the organism, non-allergic, and are resistant to physical and chemical factors. Hydroxyapatites are bioactive calcium phosphate ceramics that are compatible with tissues. Nano-sized hydroxyapatite has been produced to increase their bioactivity. Although there are advantages to the use of nanoparticles in medicine and therapy, the potential toxicity of these compounds on the ecosystem and human health are of concern. One of the key issues to be investigated is whether the different forms of the same nanoparticle will cause differences in genotoxicity. Herein, the potential genotoxic effects of rod and round forms of nano-sized hydroxyapatites (nHAs) were evaluated using the Allium cepa Single Cell Gel Electrophoresis (SCGE) method. Results had shown that the round form of nHA in the A. cepa meristem root tip cells caused statistically significant genotoxicity at 25 µg/mL concentration in terms of tail intensity and tail moment. This study indicated small-sized-nanohydroxyapatite-induced genotoxicity and cell death in A. cepa. This study has shown that the physical properties of nanoparticles affect potential toxicity mechanisms.