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Numerous risk factors have been associated with breast cancer (BC), exposure to metalloestrogen, like lead, being such. Since lead involvement in BC is still equivocal, we focused on lead levels in three compartments of BC patients, blood, healthy, and malignant tissues. Also, as the cholesterol role in cancer development was recognized at the beginning of the twentieth century and led to involvement in lipid profile impairment, we further extend our research on lipid profile and enzymes responsible for maintaining lipid balance in BC patients. Fifty-five women diagnosed with BC were enrolled in the study. Forty-one healthy women represented the control group. Lead levels in blood, healthy surrounding and malignant tissue, and lipid profile parameters in serum, were determined. Higher lead levels were obtained in surrounding healthy tissue samples compared to cancerous tissue samples, while blood lead levels of BC women did not differ significantly from the control group. The altered lipid profile scheme in women diagnosed with breast cancer contained significantly higher triglycerides levels (P < 0.001). Moreover, logistic regression analysis revealed triglycerides as a significant predictor of BC (OR = 2.6; P < 0.01). Although statistical significance was missing for lower paraoxonase-1 (PON-1) activities observed in BC women, multivariate logistic regression singled out PON-1 activities as significant BC predictors. The result of the present study further indicated oxidative status imbalance and tissue levels bioelements perturbation. Obtained results in the present study propose possible lead involvement in BC onset accompanied with bioelements redistribution and oxidative stress occurrence.

Mercury (Hg) is one of the most important environmental pollutants with endocrine- disrupting properties. There is little data from epidemiological studies describing the dose- response relationship between toxic metal levels and hormone levels. The aim of this study was to use the nearest neighbor matching analysis to determine the difference in Hg concentration in healthy/sick subjects with thyroid disease and to use Benchmark modeling to determine the dose- response relationship between Hg levels in the blood and thyroid-stimulating hormone (TSH) and thyroid hormones in serum. Blood samples were collected and used for Hg measurement using the ICP-MS method, and separated serum was used for hormone analysis. The study showed the existence of a statistically significant difference in Hg levels measured in healthy and sick subjects and the existence of a dose-response relationship between Hg and all measured hormones, with a narrow interval obtained for the Hg-TSH pair. The results of this research support the use of the Benchmark dose approach for the purpose of analyzing data from human studies, and our further research will be focused on examining the impact of low doses on animal models in order to determine more precise effects of low doses on the organism. Živa (Hg) je jedan od najznačajnijih zagađivača životne sredine sa osobinama endokrinog ometača. Malo je podataka iz epidemioloških studija koji opisuju odnos doza-odgovor između nivoa toksičnih metala i nivoa hormona. Cilj ovog rada bio je da primenom nearest neighbor matching analize utvrdi razliku u koncentraciji Hg kod zdravih/obolelih ispitanika od bolesti štitaste žlezde i da primenom Benchmark modelovanja utvrdi odnos doza-odgovor između nivoa Hg u krvi i tireostimulišućeg hormona (TSH) i tiroidnih hormona u serumu. Uzorci krvi su sakupljeni i korišćeni za merenje Hg uz pomoć ICP-MS metode, a izdvojeni serum korišćen je za analizu hormona. Studija je pokazala postojanje statistički značajne razlike u nivoima Hg koji su izmereni kod zdravih i bolesnih ispitanika i postojanje odnosa doza-odgovor između Hg i svih merenih hormona, pri čemu je uzak interval dobijen za Hg-TSH par. Rezultati ovog istraživanja podržavaju upotrebu Benchmark dose pristupa u svrhu analize podataka iz humanih studija, a naša dalja istraživanja će biti usmerena na ispitivanje uticaja niskih doza na životinjskim modelima, u cilju utvrđivanja preciznijih efekata niskih doza na organizam.

The present study investigated the effects of PCBs on the rat kidneys with attention given to the determination critical effect dose (CED) using the Benchmark dose (BMD) approach. Male albino Wistar rats (7 animals per group) were given by oral gavage Aroclor 1254 dissolved in corn oil at doses of 0.0, 0.5, 1, 2, 4, 8, or 16 mg/kg b.w./day for 28 days. The PCB nephrotoxicity was manifested by a dose-dependent changes in serum urea levels. The study has also revealed PCB-induced oxidative stress induction in kidneys. The observed nephrotoxic effects can be partly explained by oxidative damage of lipids and proteins in the kidneys due to observed reduced CuZnSOD activity and disturbances in antioxidant protection. Аll the renal oxidative stress parameters showed dependence on PCB oral doses as well as internal, measure kidney PCB levels. Calculated BMDL values were lower than estimated no observed adverse effect levels (NOAEL) based on the study, suggesting the importance of BMD approach use in future risk assessment.

Connections between the mixture containing bis(2- ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP) and bisphenol A (BPA) and liver injury were explored through in silico investigation and 2 in vivo models. Comparative Toxicogenomics Database (CTD), ShinyGO, ToppCluster and Cytoscape were used for bioinformatic analysis. In vivo subacute study was performed on rats - five groups (n = 6): (1) Control: corn oil, (2) DEHP: 50 mg/kg b.w./day, (3) DBP: 50 mg/kg b.w./day, (4) BPA: 25 mg/kg b.w./day, (5) MIX: DEHP + DBP + BPA. Zebrafish embryos were exposed to the investigated substances in different doses, singularly and combined (binary and ternary mixtures). Liver injury was linked to 75 DEHP, DBP, and BPA genes, mostly connected to inflammation/oxidative stress. In rats, significant alterations in redox status/bioelements and pathohistology were most notable or exclusively present in MIX (probable additive effects). BPA decreased liver area (LA) index in dose-dependent manner. DEHP (< 2 µg/mL) and DBP (≤ 5 µg/mL) reduced LA values, while their higher doses increased LA index. The effect of DBP in binary mixtures led to a lethal outcome at the two highest concentrations, while the hepatotoxicity of DEHP/DBP/BPA mixture was dictated by BPA (confirmed by the benchmark dose analysis).

Sulforaphane (SFN) is a naturally occurring molecule present in plants from Brassica family. It becomes bioactive after hydrolytic reaction mediated by myrosinase or human gastrointestinal microbiota. Sulforaphane gained scientific popularity due to its antioxidant and anti-cancer properties. However, its toxicity profile and potential to cause adverse effects remain largely unidentified. Thus, this study aimed to generate SFN-triggered adverse outcome pathway (AOP) by looking at the relationship between SFN-chemical structure and its toxicity, as well as SFN-gene interactions. Quantitative structure-activity relationship (QSAR) analysis identified 2 toxophores (Derek Nexus software) that have the potential to cause chromosomal damage and skin sensitization in mammals or mutagenicity in bacteria. Data extracted from Comparative Toxicogenomics Database (CTD) linked SFN with previously proposed outcomes via gene interactions. The total of 11 and 146 genes connected SFN with chromosomal damage and skin diseases, respectively. However, network analysis (NetworkAnalyst tool) revealed that these genes function in wider networks containing 490 and 1986 nodes, respectively. The over-representation analysis (ExpressAnalyst tool) pointed out crucial biological pathways regulated by SFN-interfering genes. These pathways are uploaded to AOP-helpFinder tool which found the 2321 connections between 19 enriched pathways and SFN which were further considered as key events. Two major, interconnected AOPs were generated: first starting from disruption of biological pathways involved in cell cycle and cell proliferation leading to increased apoptosis, and the second one connecting activated immune system signaling pathways to inflammation and apoptosis. In both cases, chromosomal damage and/or skin diseases such as dermatitis or psoriasis appear as adverse outcomes.

Cadmium (Cd) is a toxic metal, present in all matrices of the environment and a common food contaminant. Human exposure to it may elicit many diverse health impairments. The aim of this study was to assess the dietary exposure to Cd for the adult population and preschool children in Serbia using probabilistic methodology. We measured Cd in 11,227 food samples belonging to 50 food items on the Serbian market. Cd was detected in 90% of the tested food items, and in 30.8% of the overall tested samples. The food item that contributed the most to total dietary Cd intake was potatoes (median Cd concentration of 7 ng/g) in adults, and fruit and vegetable juices in children (median Cd concentration of 19 ng/g). Weekly Cd intake shown as 50th and 95th percentiles were 2.54 and 4.74 µg/kg bw in the adult population, and 3.29 and 4.93 µg/kg bw in children. The results of this study are rather preliminary and should be considered as an indication of the need for further, more refined research, which would contribute to a more realistic risk assessment as a high-priority approach, especially in the case of vulnerable subpopulations such as children.

Testis cancer (TC) is the most common malignancy of young men. Current evidence from studies, alongside genetics and hormonal status, suggests a significant role of toxic metals, cadmium (Cd) and lead (Pb), in the origin and development of TC. Besides oxidative stress and endocrine disruption, interaction with bioelements is one of the critical mechanisms of Cd and Pb toxicity and malign transformation. This study aimed to investigate metal levels in blood, healthy, and tumor testis tissue and to reveal hormone, oxidative status, and bioelements levels in patients with TC. The study enrolled 52 patients with TC and 61 healthy volunteers. Toxic metals and bioelements levels were analyzed by atomic absorption spectrophotometry (AAS) while electrochemiluminescence immunoassay (ECLIA) and spectrophotometry methods were used for hormone and oxidative parameters evaluation. Significantly higher blood Cd levels were depicted in TC cohort. Furthermore, blood Cd elevation was associated with a 1.98 higher probability of TC developing. However, a metal concentration between healthy and tumor testis tissue did not differ significantly. Lower levels of estradiol and testosterone, established in a cohort of TC patients, followed the significant role of hormones in TC development. At the same time, ischemia-modified albumin (IMA) has been recognized as a parameter with very good accuracy as a potential diagnostic marker for TC. The study revealed different distribution patterns of copper (Cu) and zinc (Zn) in the three compartments of the patients, as well significant correlation between essential metals Cu/Zn and toxic metals Cd/Pb indicating metal-metal interactions as pivotal mechanisms of metals toxicity.

Toxic metals (cadmium (Cd), lead (Pb), mercury (Hg) and arsenic (As)) and plastificators (bis (2 – ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP)) and bisphenol A (BPA)) have been suggested to aid in colorectal carcinoma (CRC) advancement. Sulforaphane (SFN), isothiocyanate from cruciferous vegetables, diminishes chemical carcinogenesis susceptibility, but has been shown to act as a friend or a foe depending on various factors. By conducting the mechanistic toxicogenomic data mining approach, this research aimed to determine if SFN can alleviate toxic-metal and/or phthalate/BPA mixture-induced CRC at the gene level. Comparative Toxicogenomics Database, ToppGene Suite portal, Cytoscape software, InteractiVenn and Gene Expression Omnibus (GEO) database (GEO2R tool) was used. Among the mutual genes for all the investigated substances, SFN had a protective impact only through PTGS2. Other proposed protective SFN-targets included ABCA1, ALDH2, BMP2, DPYD, MYC, SLCO2A1, and SOD2, only in the case of phthalates/BPA exposure. The only additional gene relevant for SFN protection against the toxic metal mixture-induced CRC was ABCB1. Additionally, the majority of the top 15 molecular pathways extracted for SFN impact on phthalate and BPA mixture-linked CRC development were directly linked with cancer development, which was not the case with the toxic metal mixture. The current research has indicated that SFN is a more effective chemoprotective agent against CRC induced by phthalates/BPA mixture than by toxic-metal mixture. It has also presented the value of computational methods as a simple tool for directing further research, selecting appropriate biomarkers and exploring the mechanisms of toxicity.

Exposure to low levels of a toxic metal lead (Pb) affects human health, and its effect as an endocrine disruptor has been reported. However, the precise role of Pb in endocrine health is still unclear because no dose-response relationship has been established for such an effect. The present study aimed to examine blood Pb levels (BLLs) in relation to serum levels of free triiodothyronine (fT3), free thyroxine (fT4), thyroid stimulating hormone (TSH), and insulin in 435 nonoccupationally exposed Serbian subjects (218 women, 217 men, 18–94 years of age, mean age 48). In addition, benchmark dose (BMD) values were calculated for these endocrine endpoints using the PROAST 70.1 software. An explicit dose-response dependency between BLL and TSH, fT3, fT4, testosterone, and insulin serum levels was evident from BMD modelling. The results support the positive association between BLLs and serum insulin levels, with observed dose-response and calculated BMD values of 1.49 and 0.74 μg Pb/dL in males and females, respectively. Collectively, our findings reported potential endocrine-disrupting effects of Pb at the environmental exposure levels experienced by current Serbian population. They also strengthen the notion that the blood Pb threshold level for an endocrine effect is low.

Most Pb and Cd neurotoxicity studies investigate exposure to either of the toxic metals alone, while data on co-exposure are scarce. The aim of our study was to fill that gap by investigating acute combined effects of Pb and Cd on redox and essential metal status in the brain of Wistar rats. Animals were randomised in four groups of six to eight rats, which received 15 or 30 mg/kg of Cd, 150 mg/kg of Pb, or 150 mg/kg of Pb + 15 mg/kg of Cd by gavage. The fifth, control, group received distilled water only. Co-treatment with Pb and Cd induced significant increase in malondialdehyde (MDA) and thiobarbituric acid-reactive substances (TBARS) compared to control and groups receiving either metal alone. This is of special importance, as MDA presence in the brain has been implicated in many neurodegenerative disorders. The groups did not significantly differ in Zn, Cu, Mn, and Fe brain levels. Our findings highlight the importance of metal mixture studies. Neurotoxicity assessments of single chemicals do not provide a real insight into exposure to mixtures in real life. Further research should look into interactions between these metals to reveal complex molecular mechanisms of their neurotoxicity., Dosadašnji podatci o neurotoksičnosti olova (Pb) i kadmija (Cd) uglavnom su opisani nakon izloženosti pojedinačnim metalima, a podatci o neurotoksičnom djelovanju smjese tih dvaju metala prilično su oskudni. Cilj ovoga rada bio je ispitati učinak akutnoga izlaganja smjesi olova i kadmija na parametre oksidacijskoga stresa i status bioelemenata u mozgu štakora. Životinje su bile podijeljene u pet skupina: Cd15 (15 mg/kg), Cd30 (30 mg/kg), Pb150 (150 mg/kg), Pb150+Cd15 i kontrolna, netretirana skupina. Smjesa olova i kadmija dovela je do značajno viših vrijednosti malondialdehida (MDA) i drugih produkata u mozgu štakora u usporedbi s kontrolnom skupinom i obama pojedinačnim metalima. To je iznimno važno, imajući u vidu da je prisutnost MDA-a u mozgu povezana s mnogim neurodegenerativnim poremećajima. Nije dobivena statistički značajna razlika između ispitivanih skupina u razinama cinka (Zn), bakra (Cu), mangana (Mn) I željeza (Fe). Rezultati ovoga istraživanja važan su doprinos budućim istraživanjima smjesa i upućuju na to da istraživanja toksičnosti u kojima se procjenjuje neurotoksičnost pojedinačnih kemikalija ne pružaju stvarni uvid u neurotoksičnost njihovih smjesa kojima smo izloženi u stvarnom životu. Dobiveni rezultati otvaraju daljnja pitanja o interakciji i mehanizmima toksičnosti smjese tih metala.

Cadmium (Cd), one of the most important environmental pollutants, can cause a number of toxic effects. These effects are the result of more than one mechanisms of toxicity, all interrelated in their complexity. Thus, it is difficult to identify a fine line between these mechanisms of Cd toxicity, making their understanding highly complicated. The most important mechanisms by which Cd manifests its toxic effects include changes in gene expression and inhibition of damaged DNA repair, interference of apoptosis and autophagy, oxidative stress, and interaction with bioelements. In this review, we will give a brief overview of the recent developments and findings on the most relevant general and specific mechanisms and molecular pathways of Cd toxicity.

Cadmium (Cd) is a toxic metal, present in all matrices of the environment. Cadmium is a common food contaminant and human exposure to it may elicit many diverse health impairments.The aim of this study was to assess the dietary exposure to Cd for the adult population and preschool children in Serbia using the probabilistic methodology. We have measured Cd content in 11,227 food samples belonging to 50 food groups available on the Serbian market. Cadmium was detected in 90% of the tested food groups, and in 31% of the total samples. Food groups that contributed the most to total dietary Cd intake were potatoes in the adult population, and fruit and vegetable juices in children. Consumption data were taken from the GEMS/Food Consumption Cluster Diets database Calculated HI values showed that 54.4% of the adult population and 84.4% of the population of preschool children were under the unacceptable risk of Cd exposure. The results of this study are based on a worst-case scenario. Thus, they are rather preliminary and should be considered as an indication of the need for further, more refined input data, particularly in terms of consumption database, which would altogether contribute to the more realistic risk assessment as a high priority approach, especially in the case of the vulnerable subpopulations such as children.

The objectives of the study were to simulate low-level Pb exposure scenario in an animal model and to examine reproductive adverse effects. Based on obtained data, we have performed Benchmark dose (BMD)-response modelling. Male Wistar rats were randomized in seven groups (n = 6): one control and six treated with: 0.1, 0.5, 1, 3, 7, and 15 mg Pb/kg body weight, daily for 28 days by oral gavage. The rats were sacrificed and the blood and testes were used for further analysis of testosterone levels in serum, testicular essential metal levels and histological analysis. The Pb treatment led to a dose-dependent decrease of serum testosterone levels with a negative trend (BMDI 0.17–6.13 mg Pb/kg). Increase of Zn (dose-dependent, BMDI 0.004–19.7 mg Pb/kg) and Cu and a decrease of Mn testicular levels were also detected with unscathed histology of the testes. The presented results might be used in further evaluation of the point of departure in human health risk assessment for Pb.

Lead (Pb) is a toxic metal that affects almost all human’s system and organs, with the nervous system as the most sensitive. Better understanding of the Pb neurobehavioral effects and neurotoxicity requires realistic study scenarios based on low level exposure. The aim of this study was to determine neurotoxic effects and mechanisms of Pb in six low doses and to establish dose-response relationship for these effects and related Benchmark dose (BMD). Forty-two, male albino Wistar rats were randomized into seven groups, control and Pb-exposed: 0.1, 0.5, 1, 3, 7 and 15 mg Pb/kg body weight/day (oral gavage) for 28 days. Behavioural tests (Elevated plus maze test, Spontaneous locomotor activity test and Novel object recognition test) were conducted in the last week of experiment, in the control, lower (0.5 mg Pb/kg), middle (3 mg Pb/kg) and higher (15 mg Pb/kg) dose groups. The acetylcholinesterase activity, oxidative status and essential elements levels (Cu, Zn, Mn and Fe) were measured in brain tissue along with histological analyses. External and internal dose-response analyses were performed using PROASTweb 70.1 software. The results have shown that subacute exposure to very low doses of Pb resulted in memory deficits in rats that was accompanied with acetylcholinesterase enzyme activity decrease. The observed hyperactive behaviour was accompanied by dose-dependent induction of brain oxidative stress and Zn elevation. The histological alterations in Purkinje cells were only detected in the group treated with the highest Pb dose. The lowest BMD considering entire oxidative status was calculated based on total oxidative status (4.5e-06 mg Pb/kg b.w./day). The findings reported in our study may be beneficial in further evaluating the health consequences and human health risk assessment of low-level Pb exposure.

Considering that some researchers point to a possible influence of air pollution on COVID-19 transmission, severity, and death rate, the aim of our in silico study was to determine the relationship between the key air pollutants [sulphur dioxide (SO), carbon monoxide (CO), 2particulate matter (PMx), nitrogen dioxide (NO2), and ozone (O3)] and COVID-19 complications using the publicly available toxicogenomic analytical and prediction tools: (i) Comparative Toxicogenomic Database (CTD) to identify genes common to air pollutants and COVID-19 complications; (ii) GeneMANIA to construct a network of these common and related genes; (iii) ToppGene Suite to extract the most important biological processes and molecular pathways; and (iv) DisGeNET to search for the top gene-disease pairs. SO2, CO, PMx, NO2, and O3 interacted with 6, 6, 18, 9, and 12 COVID-19-related genes, respectively. Four of these are common for all pollutants (IL10, IL6, IL1B, and TNF) and participate in most (77.64 %) physical interactions. Further analysis pointed to cytokine binding and cytokine-mediated signalling pathway as the most important molecular function and biological process, respectively. Other molecular functions and biological processes are mostly related to cytokine activity and inflammation, which might be connected to the cytokine storm and resulting COVID-19 complications. The final step singled out the link between the CEBPA gene and acute myelocytic leukaemia and between TNFRSF1A and TNF receptor-associated periodic fever syndrome. This indicates possible complications in COVID-19 patients suffering from these diseases, especially those living in urban areas with poor air quality.

This study aimed to investigate the effect of 150 mg/L sodium fluoride (NaF) on redox status parameters and essential metals [copper (Cu), iron (Fe), and zinc (Zn)] in the blood, liver, kidney, brain, and spleen of Wistar rats and to determine the protective potential of selenium (Se) against fluoride (F-) toxicity. Male Wistar rats were randomly distributed in groups of five (n=5) receiving tap water (control) or water with NaF 150 mg/L, NaF 150 mg/L + Se 1.5 mg/L, and Se 1.5 mg/L solutions ad libitum for 28 days. Fluorides caused an imbalance in the redox and biometal (Cu, Fe, and Zn) status, leading to high superoxide anion (O2.-) and malondialdehyde (MDA) levels in the blood and brain and a drop in superoxide dismutase (SOD1) activity in the liver and its increase in the brain and kidneys. Se givenwith NaF improved MDA, SOD1, and O2.- in the blood, brain, and kidneys, while alone it decreased SH group levels in the liver and kidney. Biometals both reduced and increased F- toxicity. Further research is needed before Se should be considered as a promising strategy for mitigating F- toxicity., Cilj ovog istraživanja bio je utvrditi djelovanje 150 mg/L natrijevog fluorida (NaF) na redoks-status i koncentracije esencijalnih elemenata [bakar (Cu), željezo (Fe) i cink (Zn)] u krvi, jetri, bubrezima, mozgu i slezeni Wistar štakora te mogući zaštitni učinak selena (Se) od toksičnosti prouzročene fluoridom (F-). Mužjaci Wistar štakora nasumično su razvrstani u četiri skupine (n=5), nakon čega su 28 dana konzumirali običnu vodu ili vodu s otopinom NaF 150 mg/L, NaF 150 mg/L + Se 1,5 mg/L ili Se 1,5 mg/L. Izloženost fluoridu dovela je do poremećaja redoks-parametara i koncentracija istraživanih biometala. Utvrđene su povišene razine superoksid aniona (O2.-) i malondialdehida (MDA) u krvi i mozgu, smanjena aktivnost superoksid dismutaze (SOD1) u jetri te njezin porast u mozgu i bubrezima. Nadomjesni Se u kombinaciji s NaF pozitivno je utjecao na razine MDA, SOD1 i O2.- u krvi, mozgu i bubrezima, a sâm Se smanjio je razine SH skupina u jetri i bubrezima. Izloženost fluoridu uzrokovala je sniženje, ali i porast koncentracija biometala. Nužna su dodatna istraživanja kako bi se ispitali antioksidacijski učinci Se na toksičnost izazvanu F-.

Persistent organic pollutants (POPs) are considered as potential obesogens that may affect adipose tissue development and functioning, thus promoting obesity. However, various POPs may have different mechanisms of action. The objective of the present review is to discuss the key mechanisms linking exposure to POPs to adipose tissue dysfunction and obesity. Laboratory data clearly demonstrate that the mechanisms associated with the interference of exposure to POPs with obesity include: (a) dysregulation of adipogenesis regulators (PPARγ and C/EBPα); (b) affinity and binding to nuclear receptors; (c) epigenetic effects; and/or (d) proinflammatory activity. Although in vivo data are generally corroborative of the in vitro results, studies in living organisms have shown that the impact of POPs on adipogenesis is affected by biological factors such as sex, age, and period of exposure. Epidemiological data demonstrate a significant association between exposure to POPs and obesity and obesity-associated metabolic disturbances (e.g., type 2 diabetes mellitus and metabolic syndrome), although the existing data are considered insufficient. In conclusion, both laboratory and epidemiological data underline the significant role of POPs as environmental obesogens. However, further studies are required to better characterize both the mechanisms and the dose/concentration-response effects of exposure to POPs in the development of obesity and other metabolic diseases.

Exposure to toxic metals, including lead (Pb), were found as important risk factor for cardiovascular diseases. The aim of the study was to simulate low-level subacute Pb exposure scenario and to determine redox status, redox scores (OXY-score, damage score and protective score) and copper (Cu), zinc (Zn), iron (Fe) and manganese (Mn) levels in cardiac tissue of Wistar rats. Based on the obtained results we have established dose-toxic response relationship and derived Benchmark dose. The male Wistar rats were divided in seven groups (n = 6), six threated groups that received 0.1; 0.5; 1; 3; 7; 15 mg Pb/kg body weight/day for 28 days, by oral gavage and control group. The results of the presented study demonstrated that Pb affect cardiac tissue by inducing production of superoxide anion radical (O2.-) and consequently raising malondialdehyde (MDA) levels. The positive trend in OXY-score and damage score were determined. Effect size analysis showed that the main toxic effects were oxidative damage and elevation of MDA. The lowest BMD was calculated for MDA (2.2e-0.6 mg Pb/kg b.w./day). Obtained BMD may be useful in further assessing point of departure in the human health risks assessment of low-level Pb exposure scenario.

The major goal of this study was to estimate the correlations and dose-response pattern between the measured blood toxic metals (cadmium (Cd), mercury (Hg), chromium (Cr), nickel (Ni))/metalloid (arsenic (As)) and serum insulin level by conducting Benchmark dose (BMD) analysis of human data. The study involved 435 non-occupationally exposed individuals (217 men and 218 women). The samples were collected at health care institutions in Belgrade, Serbia, from January 2019 to May 2021. Blood sample preparation was conducted by microwave digestion. Cd was measured by graphite furnace atomic absorption spectrophotometry (GF-AAS), while inductively coupled plasma-mass spectrometry (ICP-MS) was used to measure Hg, Ni, Cr and As. BMD analysis of insulin levels represented as quantal data was done using the PROAST software version 70.1 (model averaging methodology, BMD response: 10%). In the male population, there was no correlation between toxic metal/metalloid concentrations and insulin level. However, in the female population/whole population, a high positive correlation for As and Hg, and a strong negative correlation for Ni and measured serum insulin level was established. BMD modelling revealed quantitative associations between blood toxic metal/metalloid concentrations and serum insulin levels. All the estimated BMD intervals were wide except the one for As, reflecting a high degree of confidence in the estimations and possible role of As as a metabolic disruptor. These results indicate that, in the case of As blood concentrations, even values higher than BMD (BMDL): 3.27 (1.26) (male population), 2.79 (0.771) (female population), or 1.18 (2.96) μg/L (whole population) might contribute to a 10% higher risk of insulin level alterations, meaning 10% higher risk of blood insulin increasing from within reference range to above reference range. The obtained results contribute to the current body of knowledge on the use of BMD modelling for analysing human data.

Colorectal cancer (CRC) is a significant global health burden that ranks as the third most diagnosed and second most common cause of cancer related deaths worldwide. New therapeutic strategies include chemoprevention and use of molecules which could prevent, suppress or reverse CRC progression such as sulforaphane (SFN). However, evidences about its safety in CRC patients are still lacking. The aim of this in silico investigation was to predict SFN-induced adverse effects in CRC patients by computational analysis. The study showed that 334 genes were consistently dysregulated in CRC (223 downregulated and 111 upregulated), while 38 were recognized as significant and might be used as predictive biomarkers for overall survival and metastasis (TCGA, GEO, R studio). Among them, SFN interacted with 86 genes, out of which 11 were marked as significant (correlate with overall prognosis and metastasis). Sulforaphane potentiates the overexpression of TIMP1, AURKA, and CEP55, and promotes inhibition of CRYAB, PLCE1, and MMP28, that might lead to the progression of CRC (CTD). Pathway enrichment analysis revealed that SFN stimulated Transcriptional activation of RUNX2, AURKA activation by TPX2, IL-10 signaling, while inhibited Differentiation of White and Brown Adipocyte process, an underlying pathway which inactivation led to obesity (Cytoscape ClueGo + CluePedia, DAVID). Thus, genome signature of CRC patients could serve as important factor when addressing the risk-to-benefit profile of SFN. Patients with colon cancer and increased expression of TIMP1, CCL20, SPP1, AURKA, CEP55, NEK2, SOX9 and CDK1, or downregulation of CRYAB, PLCE1, MMP28, BMP2 and PLAC8 may not be ideal candidates for SFN chemoprevention.

This paper aims to present the importance of the benchmark dose (BMD) as a point of departure (the lowest dose or concentration in the experiment that deviates from the response that differs from the normal response) in toxicological risk assessment, as well as to present commonly used software for its calculation (BMDS and PROAST). Benchmark dose is defined as a statistical lower confidence limit of a dose that results in a small change in effect (5-10%) in comparison with the control value. The BMD approach is considered a substitution for the NOAEL approach, which uses the highest observed no-effect level (NOAEL) to obtain the reference dose. The BMD approach is a methodically more forward-thinking technique than the NOAEL approach because it has statistical power and provides a wide range of dose-response relationships and allows the determination of their uncertainty and variability. Moreover, the BMD approach contributes to the reduction of experimental animals in toxicity studies. Therefore, the European Food Safety Authority (EFSA) recommends the use of BMDL10values for quantal and BMDL05for continuous data. Cilj ovog rada je da predstavi značaj granične benchmark doze (engl. benchmark dose, BMD) kao polaznog doznog nivoa (najniže doze ili koncentracije u eksperimentu koja odstupa od normalnog odgovora) u toksikološkoj proceni rizika, kao i da prikaže najčešće korišćene softvere za njeno izračunavanje (BMDS i PROAST). Benchmark doza predstavlja statističku donju granicu pouzdanosti doze koja dovodi do malog povećanja efekta (5-10%) u odnosu na kontrolnu vrednost. Benchmark pristup predstavlja alternativu NOAEL (engl. no observed adverse effects level, NOAEL) pristupu, u kome se u svrhu dobijanja referentnih vrednosti koristi najviša doza koja ne izaziva štetan efekat. Benchmark pristup naučno je napredniji metod od tradicionalnog NOAEL pristupa, jer je statistički utemeljen, daje širok opseg podataka o odnosu doza-odgovor i omogućava kvantifikaciju njihove nesigurnosti i varijabilnosti. Takođe, BMD pristup doprinosi smanjenju broja eksperimentalnih životinja u toksikološkim studijama. Samim tim, Evropska agencija za bezbednost hrane (EFSA) preporučuje primenu doza BMDL10 za kvantalne i BMDL05 za kontinuirane podatke.

Although profoundly studied, etiology of pancreatic cancer (PC) is still rather scarce. Some of established risk factors of PC are connected to an increased cadmium (Cd) body burden. Hence, the aim of this study was to investigate the role of this environmental pollutant in PC development by conducting human observational, experimental and in vitro studies.The case-control study included 31 patients with a histologically based diagnosis of exocrine PC subjected to radical surgical intervention as cases and 29 accidental fatalities or subjects who died of a nonmalignant illness as controls. Animal study included two treated groups of Wistar rats (15 and 30 mg Cd/kg b.w) and untreated control group, sacrificed 24 h after single oral exposure. In in vitro study pancreas hTERT-HPNE and AsPC-1 cells were exposed to different Cd concentrations corresponding to levels measured in human cancerous pancreatic tissue.Cd content in cancer tissue significantly differed from the content in healthy controls. Odds ratio levels for PC development were 2.79 (95% CI 0.91–8.50) and 3.44 (95% CI 1.19–9.95) in the third and fourth quartiles of Cd distribution, respectively. Animal study confirmed Cd deposition in pancreatic tissue. In vitro studies revealed that Cd produces disturbances in intrinsic pathway of apoptotic activity and the elevation in oxidative stress in pancreatic cells.This study presents three different lines of evidence pointing towards Cd as an agent responsible for the development of PC. Keywords: Pancreatic cancer, Cadmium, Carcinogenesis, Risk factors

This study aimed to investigate the potential hepatotoxicity, nephrotoxic, and hematotoxic effects of simultaneous occupational low-level exposure of shoe workers to a mixture of organic solvents. The study included 16 male and 55 female workers and non-exposed subjects (

Cadmium (Cd), one of the most abundant environmental pollutants, is considered to have endocrine disrupting properties. However, data on the dose-response relationship between Cd dose and levels of hormones have been insufficiently studied, especially in human data sets. Thus, the aim of this study was to determine the possibility of analyzing data obtained from a case- control study in female patients with benign/malignant breast tumors, using the Benchmark dose (BMD) concept. The collected data on Cd levels in breast tissue and estrogen serum levels were processed in PROAST software using different variables. The dose-response relationship between the internal dose of Cd and estradiol levels in the serum was investigated and BMD intervals were calculated. The dose-response relationship between the Cd concentration in breast tissue and the estradiol serum level was shown, indicating lower estradiol serum levels as a consequence of higher Cd concentrations in breast tissue. As one of the few studies analyzing human data using the BMD approach, these findings could have a pivotal role in dose response analysis of data collected from human studies. Kadmijum (Cd), jedan od najzastupljenijih zagađivača životne sredine, dokazan je endokrini ometač. Međutim, podaci o postojanju odnosa između doze Cd i odgovora-nivoa hormona nisu dovoljno istraženi, posebno podaci sakupljeni iz studija na ljudima. Stoga je cilj ove studije bio da se utvrdi mogućnost analize podataka dobijenih iz studije slučaja-kontrole kod pacijentkinja sa benignim/malignim tumorom dojke, primenom koncepta Benčmark doze (BMD). Prikupljeni podaci o nivoima Cd u tkivu dojke i serumskim nivoima estrogena obrađeni su u PROAST softveru uz korišćenje različitih varijabli. Ispitivan je odnos doza-odgovor između unutrašnje doze Cd (koncentracije u tkivu dojke) i estradiola u serumu i izračunati BMD intervali. Utvrđeno je postojanje odnosa između koncentracije Cd u tkivu dojke i nivoa estradiola u serumu koje ukazuje na niže nivoe estradiola u serumu kao posledica veće koncentracije Cd u tkivu dojke. Kao jedno od retkih istraživanja ovog tipa, dobijeni rezultati mogli bi predstavljati početak otkrivanja mogućnosti analize podataka prikupljenih u studijama na ljudima primenom BMD pristupa.

Linkage between bis(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), and bisphenol A (BPA) co-exposure and type 2 diabetes mellitus (T2DM), as well as ability of multi-strained probiotic to reduce DEHP, DBP and BPA mixture-induced oxidative damage in rat pancreas were investigated. The Comparative Toxicogenomics Database, Cytoscape software and ToppGene Suite were used for data-mining. Animals were sorted into seven groups (n = 6): (1) Control group: corn oil, (2) P: probiotic: Saccharomyces boulardii + Lactobacillus rhamnosus + Lactobacillus plantarum LP 6595 + Lactobacillus plantarum HEAL9; (3) DEHP: 50 mg/kg b.w./day, (4) DBP: 50 mg/kg b.w./day, (5) BPA: 25 mg/kg b.w./day, and (6) MIX: 50 mg/kg b.w./day DEHP + 50 mg/kg b.w/day DBP + 25 mg/kg b.w./day BPA; (7) MIX + P. Rats were sacrificed after 28 days of oral exposure. In silico investigation highlighted 44 DEHP, DBP and BPA mutual genes linked to the T2DM, while apoptosis and oxidative stress were highlighted as the main mechanisms of DEHP, DBP and BPA mixture-linked T2DM. In vivo experiment confirmed the presence of significant changes in redox status parameters (TOS, SOD and SH groups) only in the MIX group, indicating possible additive effects, while probiotic ameliorated mixture-induced redox status changes in rat pancreatic tissue.

Exposure to lead (Pb) is still rising concern worldwide, having in mind that even low-dose exposure can induce various harmful effects. Thus, in-depth knowledge of the targets of Pb toxicity and corresponding mechanisms is essential. In the presented study, the six groups (male Wistar rats, n = 6) received 0.1; 0.5; 1; 3; 7; 15 mg Pb/kg body weight/day for 28 days, each day by oral gavage, while the control group received distilled water only. All animals were sacrificed 24 h after the treatment, and blood was collected for the analysis of hematological, biochemical, oxidative status and essential elements levels. An external and internal dose-response relationship was performed using PROASTweb 70.1 software. The results showed that low doses of Pb affect hematological parameters and lipid profile after 28 days. The possible mechanisms at examined Pb dose levels were a decrease in SOD, O2•− and Cu and an increase in Zn levels. The dose-dependent nature of changes in cholesterol, HDL cholesterol, O2.-, SOD, AOPP in serum and hemoglobin, Fe, Zn, Cu in blood were obtained in this study. The most sensitive parameters that were alerted are Cu blood levels (BMDL5: 1.4 ng/kg b.w./day) and SOD activity (BMDL5: 0.5 μg/kg b.w./day). The presented results provide information that may be useful in further assessing the health risks of low-level Pb exposure.

While experimental animal investigation has historically been the most conventional approach conducted to assess drug safety and is currently considered the main method for determining drug toxicity, these studies are constricted by cost, time, and ethical approvals. Over the last 20 years, there have been significant advances in computational sciences and computer data processing, while knowledge of alternative techniques and their application has developed into a valuable skill in toxicology. Thus, the application of in silico methods in drug safety assessment is constantly increasing. They are very complex and are grounded on accumulated knowledge from toxicology, bioinformatics, biochemistry, statistics, mathematics, as well as molecular biology. This review will summarize current state-of-the-art scientific data on the use of in silico methods in toxicity testing, taking into account their shortcomings, and highlighting the strategies that should deliver consistent results, while covering the applications of in silico methods in preclinical trials and drug impurities toxicity testing. Ispitivanja na eksperimentalnim životinjama ne samo da su u prošlosti bila smatrana najkonvencionalnijim pristupom za procenu bezbednosti lekova, već su i trenutno osnovna metoda za utvrđivanje njihove toksičnosti. Međutim, ova ispitivanja su skupa, vremenski zahtevna i za njihovo sprovođenje neophodne su etičke dozvole. Tokom poslednjih 20 godina došlo je do napretka u računarskoj nauci i kompjuterskoj obradi podataka, dok se znanje o alternativnim tehnikama i njihovoj primeni razvilo u dragocenu veštinu u toksikologiji. Stoga, primena in silico metoda u proceni bezbednosti lekova neprestano raste. Ove metode su veoma složene i zasnivaju se na saznanjima iz toksikologije, bioinformatike, biohemije, statistike, matematike i molekularne biologije. Ovaj pregledni rad će rezimirati trenutna naučna saznanja koja se tiču upotrebe in silico metoda u ispitivanju toksičnosti lekova, uzimajući u obzir njihova ograničenja i ističući strategije pomoću kojih se mogu dobiti konzistentni rezultati, sa posebnim osvrtom na primenu in silico metoda u pretkliničkim ispitivanjima i ispitivanjima toksičnosti nečistoća u lekovima.

The aims of this study were to: (i) examine the toxic effects of sodium fluoride (NaF) in blood, liver, spleen, and brain cells of Wistar rats after the subacute exposure; (ii) explore the potential protective properties of selenium (Se) against fluoride toxicity after the simultaneous administration. Twenty male Wistar rats, eight weeks old, weighing approximately 140–190 g, were divided into four experimental groups (n = 5) as follows: I control-tap water; II NaF 150 ppm; III NaF 150 ppm and Se 1.5 mg/L; IV Se 1.5 mg/L, and had available water with solutions ad libitum for 28 days. DNA damage detected by comet assay was confirmed in the liver, spleen, and brain cells, but not in blood. Selenium supplementation together with NaF decreased DNA damage in liver and spleen cells. According to the histological findings, no changes were observed in spleen and brain tissues after NaF administration. Unlike the observed Se protective effect on the DNA level, no significant reduction of liver tissue injury was observed after the NaF and Se treatment, resulting in mild inflammation. Data of this study suggest that DNA damage after NaF subacute exposure at moderately high concentration was reduced in liver and spleen cells due to Se supplementation, but a similar change was not seen in the brain.

Recent research has helped clarify the role of cadmium (Cd) in various pathological states. We have demonstrated Cd involvement in pancreatic cancer, as well as the bioaccumulation of Cd in the pancreas. Bioaccumulation and increased toxicity suggest that Cd may also be involved in other pancreas-mediated diseases, like diabetes. Cd falls into the category of “hyperglycemic” metals, i.e., metals that increase blood glucose levels, which could be due to increased gluconeogenesis, damage to β-cells leading to reduced insulin production, or insulin resistance at target tissue resulting in a lack of glucose uptake. This review addresses the current evidence for the role of Cd, leading to insulin resistance from human, animal, and in vitro studies. Available data have shown that Cd may affect normal insulin function through multiple pathways. There is evidence that Cd exposure results in the perturbation of the enzymes and modulatory proteins involved in insulin signal transduction at the target tissue and mutations of the insulin receptor. Cd, through well-described mechanisms of oxidative stress, inflammation, and mitochondrial damage, may also alter insulin production in β-cells. More work is necessary to elucidate the mechanisms associated with Cd-mediated insulin resistance.

On 11th March 2020, the pandemic of the new coronavirus was declared by the World Health Organization. At the moment, there are no new registered medicines that can effectively treat the coronavirus infection. However, a number of ongoing clinical trials are investigating the efficacy and safety of the medicines which have already been registered and used for the treatment of other diseases, in the treatment of the coronavirus infection. The proposed combinations of these medicines could potentially present a safety risk, since most of these medicines have the potential to cause numerous side or toxic effects, even when used in monotherapy. Thus, the aim of this study was to review and evaluate the literature data on the toxicity of the selected individual drugs (ritonavir, lopinavir, remdesivir, chloroquine, and umifenovir) and the available clinical data concerning the possible adverse effects of the selected drug combinations (lopinavir/ritonavir+umifenovir, lopinavir/ritonavir+interferon β, chloroquine+remdesivir, and chloroquine+azithromycin). The most often reported toxic effects of these medicines such as hepatotoxicity, retinal damage, nephrotoxicity, and cardiotoxicity, together with the fact that the health status of the patients with COVID-19 disease is often complicated by co-existing illnesses and therapy implicate that the decision on the therapeutic strategy should be made with caution., Graphical abstract Image 1, Highlights • Combinations of medications in COVID-19 treatment could present a safety risk • Remdesivir can cause reversible increase in ALT and AST levels • Azithromycin and hydroxychloroquine constitute low risk of a prolonged QT interval • Screening for retinotoxicity in patients taking (hydroxy)chloroquine is recommended • The most reported toxic effects are in liver, kidney, heart, and retina