Identification of hotspots of genotoxicological and faecal pollution along the Danube and Sava rivers – the whole river surveys

The level of genotoxic pollution was assessed along the Danube River and its most significant tributary Sava River by measuring the level of DNA damage in aquatic organisms collected from the selected sites. The Danube River survey was conducted within the Joint Danube Survey 3 project in 2013 on 34 sites along the 2285 rkm using mussels (Unio sp.) and fish (Alburnus alburnus) as bioindicators. The Sava River survey was conducted within the Globaqua project in 2015 at 12 sites along 900 rkm using fish (A. alburnus/Alburnoides bipunctatus) as bioindicators. The level of DNA damage was evaluated by the comet assay in haemocytes of mussels and blood cells of fish. The level of faecal pollution along the rivers was studied in parallel with genotoxicological surveys by using the standard indicators, total coliforms, Escherichia coli and Enterococci. Quantification was performed with Colilert/Enterolert Quanti-Tray 2000 and MPN approach. Quantitative PCR (qPCR)-based assays for analysis of human- or animal-associated genetic Bacteroidetes faecal markers have been used for tracking the source of pollution (microbial source tracking -MST). The human-associated BacHum and HF183II, the ruminantassociated BacR and the pig-associated Pig2Bac fecal markers were selected. The hotspots of faecal pollution were detected at both rivers. Presence of pollution was especially evident in the countries in which the legislation related to wastewater treatment and management is not fully implemented. In the case of the Danube River the most critical section of the river was the Pannonian plain (sector VI) while in the case of the Sava River the most affected section was the lower stretch of the river. The results of MST revealed the presence of human-associated fecal markers BacHum and HF183II in the majority of the analyzed samples. High correlation was observed between the standard fecal indicators and human associated faecal markers. Within the Danube survey, the highest levels of DNA damage were recorded in organisms from the section VI, which is under the impact of untreated wastewater discharges. In 2013 the Sava River was characterized with a lower level of both faecal and genotoxic pollution in comparison with the Danube. Similar observations were found within the Sava River survey in 2015 where the level of DNA damage in fish specimens from Sava was lower in comparison with the samples from the Danube. At both rivers detected genotoxic potential was traceable to the deterioration of quality by communal and industrial wastewaters. Acknowledgements: International Commission for the Protection of the Danube River, EU Seventh Framework Program GLOBAQUA (no. 603629-ENV-2013-6.2.1). Ministry of Education, Science and Technological Development of the Republic of Serbia projects no. 173045 and 173025, the bilateral project Serbia and Austria: SER Ev. No. 451-03-01039/2015-09/33

Evaluation of genotoxic potential of tert-butylquinone and its derivatives in prokaryotic and eukaryotic test models

Tert-butylquinone (TBQ) and its alkylamino and aralkylamino derivatives are of high interest as a potential antitumor agent. Therefore, it was necessary to investigate if the compounds exert undesirable activities such as interaction with DNA molecule which could result in negative side effects in the case of their use in the diseases treatment. The major aim of this study was to investigate genotoxic potential of TBQ and selected derivatives in an acellular model by using plasmid DNA, in the prokaryotic model by the SOS/umuC assay in Salmonella typhimurium TA1535/pSK1002 and in eukaryotic models by using comet assay in human fetal lung cell line (MRC-5) and human liver cancer cell line (HepG2). Results indicated that in the acellular model TBQ and its derivatives do not interact with plasmid pUC19. In the prokaryotic model, only TBQ exerted weak genotoxic potential and only at highly cytotoxic concentrations. In eukaryotic models, genotoxic potential was detected mainly at the highest concentrations of the tested substances but the effect was lower in both cell lines in comparison with benzo[a]pyrene and etoposide which were used as positive controls. Weak genotoxic potential of tested compounds recommends them as good candidates for further testing in development of new antitumor agents. © 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group

Effect of gestational diabetes mellitus and pregnancy-induced hypertension on human umbilical vein smooth muscle KATP channels

Gestational diabetes mellitus (GDM) and pregnancy-induced hypertension (PIH) can jeopardize mother and/or fetus. Vascular ATP-sensitive potassium (KATP) channels most likely participate in the processes of diabetes and hypertension. The aim of this research was to examine whether GDM and PIH cause changes in the expression and function of KATP channels in vascular smooth muscle of human umbilical vein (HUV). Western blot and immunohistochemistry detected significantly decreased expression of Kir6.1 subunit of KATP channels in GDM and PIH, while the expression of SUR2B was unchanged. In GDM, a K+ channel opener, pinacidil caused reduced relaxation of the endothelium-denuded HUVs compared to normal pregnancy. However, its effects in HUVs from PIH subjects were similar to normal pregnancy. In all groups KATP channel blocker glibenclamide antagonized the relaxation of HUV induced by pinacidil without change in the maximal relaxations indicating additional KATP channel-independent mechanisms of pinacidil action. Iberiotoxin, a selective antagonist of large-conductance calcium-activated potassium channels, inhibited the relaxant effect of pinacidil in PIH, but not in normal pregnancy and GDM. Experiments performed in K+-rich solution confirmed the existence of K+-independent effects of pinacidil, which also appear to be impaired in GDM and PIH. Thus, the expression of KATP channels is decreased in GDM and PIH. In GDM, vasorelaxant response of HUV to pinacidil is reduced, while in PIH it remains unchanged. It is very likely that KATP channels modulation and more detailed insight in KATP channel-independent actions of pinacidil may be precious in the therapy of pathological pregnancies. © 2019 Elsevier Inc