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Kamil Kuca,1,2 Jana Zdarova Karasova,2,3 Ondrej Soukup,2 Jiri Kassa,3 Eva Novotna,2 Vendula Sepsova,2,3 Anna Horova,2 Jaroslav Pejchal,3 Martina Hrabinova,2,3 Eva Vodakova,2 Daniel Jun,2,3 Eugenie Nepovimova,1,2 Martin Valis,4 Kamil Musilek1,2 1Department of Chemistry, Faculty of Science, University of Hradec Kralove, 2Biomedical Research Center, University Hospital Hradec Kralove, 3Department of Toxicology and Military Pharmacy, Faculty of Military Health Sciences, University of Defence, 4Department of Neurology, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic Background: Intoxication by nerve agents could be prevented by using small acetylcholinesterase inhibitors (eg, pyridostigmine) for potentially exposed personnel. However, the serious side effects of currently used drugs led to research of novel potent molecules for prophylaxis of organophosphorus intoxication. Methods: The molecular design, molecular docking, chemical synthesis, in vitro methods (enzyme inhibition, cytotoxicity, and nicotinic receptors modulation), and in vivo methods (acute toxicity and prophylactic effect) were used to study bispyridinium, bisquinolinium, bisisoquinolinium, and pyridinium-quinolinium/isoquinolinium molecules presented in this study. Results: The studied molecules showed non-competitive inhibitory ability towards human acetylcholinesterase in vitro that was further confirmed by molecular modelling studies. Several compounds were selected for further studies. First, their cytotoxicity, nicotinic receptors modulation, and acute toxicity (lethal dose for 50% of laboratory animals [LD50]; mice and rats) were tested to evaluate their safety with promising results. Furthermore, their blood levels were measured to select the appropriate time for prophylactic administration. Finally, the protective ratio of selected compounds against soman-induced toxicity was determined when selected compounds were found similarly potent or only slightly better to standard pyridostigmine. Conclusion: The presented small bisquaternary molecules did not show overall benefit in prophylaxis of soman-induced in vivo toxicity. Keywords: AChE inhibitors, prophylaxis, pre-treatment, nerve agents, toxicity, soman

Protein phosphorylation is a key regulator in many biological processes, such as homeostasis, cellular signaling and communication, transcriptional and translational regulation, and apoptosis. The defects in this tightly controlled reversible post-translational modification have been described to contribute to genesis and progression of various diseases, emphasizing the importance of a systematic research of this phenomenon. Although considerable effort has been devoted to improving the analysis of phosphorylation by mass spectrometry, which is currently the method of choice to study protein phosphorylation, the detection and identification of phosphorylation sites remains challenging because of the low abundance and low ionization efficacy of phosphoproteins in comparison with nonphosphorylated proteins. To overcome this obstacle, different enrichment strategies for phosphorylated peptides/proteins have been established and optimized for subsequent mass spectrometry analysis. In this review, we will give an overview of the methods currently available for the enrichment of phosphorylated proteins and peptides including immunoprecipitation, chemical derivatization and affinity enrichment techniques.

Background: Amplification of HER2, a receptor tyrosine kinase and a breast cancer-linked oncogene, is associated with aggressive disease. HER2 protein is localised mostly at the cell membrane, but a fraction translocates to mitochondria. Whether and how mitochondrial HER2 contributes to tumorigenicity is currently unknown., Methods: We enriched the mitochondrial (mt-)HER2 fraction in breast cancer cells using an N-terminal mitochondrial targeting sequence and analysed how this manipulation impacts bioenergetics and tumorigenic properties. The role of the tyrosine kinase activity of mt-HER2 was assessed in wild type, kinase-dead (K753M) and kinase-enhanced (V659E) mtHER2 constructs., Results: We document that mt-HER2 associates with the oxidative phosphorylation system, stimulates bioenergetics and promotes larger respiratory supercomplexes. mt-HER2 enhances proliferation and invasiveness in vitro and tumour growth and metastatic potential in vivo, in a kinase activity-dependent manner. On the other hand, constitutively active mt-HER2 provokes excessive mitochondria ROS generation, sensitises to cell death, and restricts growth of primary tumours, suggesting that regulation of HER2 activity in mitochondria is required for the maximal pro-tumorigenic effect., Conclusions: mt-HER2 promotes tumorigenicity by supporting bioenergetics and optimal redox balance., (© 2024 The Authors. European Journal of Clinical Investigation published by John Wiley & Sons Ltd on behalf of Stichting European Society for Clinical Investigation Journal Foundation.)

Objectives: To describe how subclinical hypothyroidism (SubHypo) influences the quality of life (QoL) during pregnancy., Methods: In primary data collection (NCT04167423), thyroid stimulating hormone (TSH), free thyroxine (FT4), thyroid peroxidase antibodies, generic quality of life (QoL; 5-level version of EQ-5D [EQ-5D-5L]), and disease-specific QoL (ThyPRO-39) were measured among pregnant women. SubHypo during each trimester was defined according to the 2014 European Thyroid Association guidelines (TSH > 2.5, 3.0, and 3.5 IU/L, respectively; with normal FT4). Path analysis described relationships and tested mediation. Linear ordinary least squares, beta, tobit, and two-part regressions were used to map ThyPRO-39 and EQ-5D-5L. Alternative SubHypo definition was tested in sensitivity analysis., Results: A total of 253 women at 14 sites (31 ± 5 years old, 15 ± 6 weeks pregnant) completed the questionnaires. Sixty-one (26%) had SubHypo and differed from 174 (74%) euthyroid women in smoking history (61% vs 41%), primiparity (62% vs 43%) and TSH level (4.1 ± 1.4 vs 1.5 ± 0.7 mIU/L, P < .001). EQ-5D-5L utility in SubHypo (0.89 ± 0.12) was lower than that in euthyroid (0.92 ± 0.11; P = .028) even after adjustment (difference -0.04, P = .033), whereas ocular (P = .001, ThyPRO-39), cognitive symptoms (P = .043), anxiety (P < .0001), and the composite score were higher. The impact of SubHypo on utility was mediated by anxiety. Results were confirmed by sensitivity analysis. Final mapping equation (ordinary least squares) includes goiter symptoms, anxiety, upset stomach, composite score (ThyPRO-39), FT4 levels, and week of pregnancy (determination coefficient 0.36)., Conclusion: This is the first QoL mapping of SubHypo during pregnancy and the first evidence that SubHypo is associated with a negative impact on QoL. The effect is mediated by anxiety. EQ-5D-5L utilities can be generated based on ThyPRO-39 scores collected in pregnant euthyroid and patients with SubHypo., (Copyright © 2023. Published by Elsevier Inc.)

Mitochondrial oxidative phosphorylation (OXPHOS) generates ATP, but OXPHOS also supports biosynthesis during proliferation. In contrast, the role of OXPHOS during quiescence, beyond ATP production, is not well understood. Using mouse models of inducible OXPHOS deficiency in all cell types or specifically in the vascular endothelium that negligibly relies on OXPHOS-derived ATP, we show that selectively during quiescence OXPHOS provides oxidative stress resistance by supporting macroautophagy/autophagy. Mechanistically, OXPHOS constitutively generates low levels of endogenous ROS that induce autophagy via attenuation of ATG4B activity, which provides protection from ROS insult. Physiologically, the OXPHOS-autophagy system (i) protects healthy tissue from toxicity of ROS-based anticancer therapy, and (ii) provides ROS resistance in the endothelium, ameliorating systemic LPS-induced inflammation as well as inflammatory bowel disease. Hence, cells acquired mitochondria during evolution to profit from oxidative metabolism, but also built in an autophagy-based ROS-induced protective mechanism to guard against oxidative stress associated with OXPHOS function during quiescence. Abbreviations : AMPK: AMP-activated protein kinase; AOX: alternative oxidase; Baf A: bafilomycin A 1 ; CI, respiratory complexes I; DCF-DA: 2',7'-dichlordihydrofluorescein diacetate; DHE: dihydroethidium; DSS: dextran sodium sulfate; ΔΨmi: mitochondrial inner membrane potential; EdU: 5-ethynyl-2'-deoxyuridine; ETC: electron transport chain; FA: formaldehyde; HUVEC; human umbilical cord endothelial cells; IBD: inflammatory bowel disease; LC3B: microtubule associated protein 1 light chain 3 beta; LPS: lipopolysaccharide; MEFs: mouse embryonic fibroblasts; MTORC1: mechanistic target of rapamycin kinase complex 1; mtDNA: mitochondrial DNA; NAC: N-acetyl cysteine; OXPHOS: oxidative phosphorylation; PCs: proliferating cells; PE: phosphatidylethanolamine; PEITC: phenethyl isothiocyanate; QCs: quiescent cells; ROS: reactive oxygen species; PLA2: phospholipase A2, WB: western blot.

Alisertib (MLN8237), a novel Aurora A kinase inhibitor, is currently being clinically tested in late-phase trials for the therapy of various malignancies. In the present work, we describe alisertib's potential to perpetrate pharmacokinetic drug-drug interactions (DDIs) and/or to act as an antagonist of multidrug resistance (MDR). In accumulation assays, alisertib potently inhibited ABCC1 transporter, but not ABCB1 or ABCG2. The results of molecular modeling suggested a bifunctional mechanism for interaction on ABCC1. In addition, alisertib was characterized as a low- to moderate-affinity inhibitor of recombinant CYP3A4, CYP2C8, CYP2C9, CYP2C19, and CYP2D6 isoenzymes, but without potential clinical relevance. Drug combination studies revealed the capability of alisertib to synergistically antagonize ABCC1-mediated resistance to daunorubicin. Although alisertib exhibited substrate characteristics toward ABCB1 transporter in monolayer transport assays, comparative proliferation studies showed lack of its MDR-victim behavior in cells overexpressing ABCB1 as well as ABCG2 and ABCC1. Lastly, alisertib did not affect the expression of ABCC1, ABCG2, ABCB1 transporters and CYP1A2, CYP3A4, CYP2B6 isozymes on mRNA level in various systemic and tumoral models. In conclusion, our study suggests that alisertib is a drug candidate with negligible potential for perpetrating systemic pharmacokinetic DDIs on ABCB1, ABCG2 and cytochromes P450. In addition, we introduce alisertib as an effective dual-activity chemosensitizer whose MDR-antagonistic capacities are not impaired by efflux or effect on MDR phenotype. Our in vitro findings provide important pieces of information for clinicians when introducing alisertib into the clinical area., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Entrectinib is a new tyrosine kinase inhibitor that was recently approved for the treatment of ROS1-positive metastatic non-small cell lung cancer (NSCLC). In this study, we aimed to characterize its potential to act as a modulator of pharmacokinetic cytostatic resistance and perpetrator of drug interactions. In accumulation studies, entrectinib exhibited potent inhibition of ABCB1, while only moderate interaction was recorded for ABCG2 and ABCC1 efflux transporters. Furthermore, incubation assays revealed the potential of this drug to inhibit various recombinant cytochrome P450 enzymes, which can be ranked according to inhibitory affinities as follows: CYP2C8 ≈ CYP3A4 > CYP2C9 > CYP2C19 ≈ CYP3A5 > CYP2D6 > CYP2B6 > CYP1A2. Additionally, in silico docking analysis confirmed entrectinib's interactions with ABCB1 and CYP3A4 and resolved their possible molecular background. In subsequent drug combination experiments, we demonstrated the ability of entrectinib to synergize with daunorubicin in various ABCB1-expressing cellular models. Moreover, the comparative proliferation study results suggested that the anticancer efficacy of entrectinib is not affected by the functional presence of tested ABC transporters. In contrast to ABCB1-related data, no resistance reversal effect was recorded for the combination with docetaxel in HepG2-CYP3A4 cells. In the final experimental set, we observed no significant changes in ABCB1, ABCG2, ABCC1 or CYP3A4 gene expression in NSCLC cells exposed to entrectinib. In summary, our work indicates that entrectinib may be a perpetrator of clinically relevant pharmacokinetic drug interactions and modulator of ABCB1-mediated resistance. Our in vitro results might provide a valuable foundation for future clinical investigations., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Pharmacotherapy of acute myeloid leukemia (AML) remains challenging, and the disease has one of the lowest curability rates among hematological malignancies. The therapy outcomes are often compromised by the existence of a resistant AML phenotype associated with overexpression of ABCB1 and ABCG2 transporters. Because AML induction therapy frequently consists of anthracycline-like drugs, their efficiency may also be diminished by drug biotransformation via carbonyl reducing enzymes (CRE). In this study, we investigated the modulatory potential of the CDK4/6 inhibitors abemaciclib, palbociclib, and ribociclib on AML resistance using peripheral blood mononuclear cells (PBMC) isolated from patients with de novo diagnosed AML. We first confirmed inhibitory effect of the tested drugs on ABCB1 and ABCG2 in ABC transporter-expressing resistant HL-60 cells while also showing the ability to sensitize the cells to cytotoxic drugs even as no effect on AML-relevant CRE isoforms was observed. All tested CDK4/6 inhibitors elevated mitoxantrone accumulations in CD34 + PBMC and enhanced accumulation of mitoxantrone was found with abemaciclib and ribociclib in PBMC of FLT3-ITD - patients. Importantly, the accumulation rate in the presence of CDK4/6 inhibitors positively correlated with ABCB1 expression in CD34 + patients and led to enhanced apoptosis of PBMC in contrast to CD34 - samples. In summary, combination therapy involving CDK4/6 inhibitors could favorably target multidrug resistance, especially when personalized based on CD34- and ABCB1-related markers.

Ensartinib (X-396) is a promising tyrosine kinase inhibitor currently undergoing advanced clinical evaluation for the treatment of non-small cell lung cancer. In this work, we investigate possible interactions of this promising drug candidate with ATP-binding cassette (ABC) drug efflux transporters and cytochrome P450 biotransformation enzymes (CYPs), which play major roles in multidrug resistance (MDR) and pharmacokinetic drug-drug interactions (DDIs). Accumulation studies showed that ensartinib is a potent inhibitor of ABCB1 and ABCG2 transporters. Additionally, incubation experiments with recombinant CYPs showed that ensartinib significantly inhibits CYP3A4 and CYP2C9. Subsequent molecular docking studies confirmed these findings. Drug combination experiments demonstrated that ensartinib synergistically potentiates the antiproliferative effects of daunorubicin, mitoxantrone, and docetaxel in ABCB1, ABCG2, and CYP3A4-overexpressing cellular models, respectively. Advantageously, ensartinib's antitumor efficiency was not compromised by the presence of MDR-associated ABC transporters, although it acted as a substrate of ABCB1 in Madin-Darby Canine Kidney II (MDCKII) monolayer transport assays. Finally, we demonstrated that ensartinib had no significant effect on the mRNA-level expression of examined transporters and enzymes in physiological and lung tumor cellular models. In conclusion, ensartinib may perpetrate clinically relevant pharmacokinetic DDIs and modulate ABCB1-, ABCG2-, and CYP3A4-mediated MDR. The in vitro findings presented here will provide a valuable foundation for future in vivo investigations., Competing Interests: The authors declare no conflict of interest.

Alectinib is a tyrosine kinase inhibitor currently used as a first-line treatment of anaplastic lymphoma kinase-positive metastatic nonsmall cell lung cancer (NSCLC). In the present work, we investigated possible interactions of this novel drug with ATP-binding cassette (ABC) drug efflux transporters and cytochrome P450 (P450) biotransformation enzymes that play significant roles in the phenomenon of multidrug resistance (MDR) of cancer cells as well as in pharmacokinetic drug-drug interactions. Using accumulation studies in Madin-Darby canine kidney subtype 2 (MDCKII) cells alectinib was identified as an inhibitor of ABCB1 and ABCG2 but not of ABCC1. In subsequent drug combination studies, we demonstrated the ability for alectinib to effectively overcome MDR in ABCB1- and ABCG2-overexpressing MDCKII and A431 cells. To describe the pharmacokinetic interaction profile of alectinib in a complete fashion, its possible inhibitory properties toward clinically relevant P450 enzymes (i.e., CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP3A4, or CYP3A5) were evaluated using human P450-expressing insect microsomes, revealing alectinib as a poor interactor. Advantageously for its use in pharmacotherapy, alectinib further exhibited negligible potential to cause any changes in expression of ABCB1 , ABCG2 , ABCC1 , CYP1A2 , CYP3A4 , and CYP2B6 in intestine, liver, and NSCLC models. Our in vitro observations might serve as a valuable foundation for future in vivo studies that could support the rationale for our conclusions and possibly enable providing more efficient and safer therapy to many oncological patients., (Copyright © 2019 by The American Society for Pharmacology and Experimental Therapeutics.)

Daunorubicin (DAUN) has served as an anticancer drug in chemotherapy regimens for decades and is still irreplaceable in treatment of acute leukemias. The therapeutic outcome of DAUN-based therapy is compromised by its cardiotoxicity and emergence of drug resistance. This phenomenon is often caused by pharmacokinetic mechanisms such as efflux of DAUN from cancer cells through ATP-binding cassette (ABC) transporters and its conversion to less cytostatic but more cardiotoxic daunorubicinol (DAUN-OL) by carbonyl reducing enzymes (CREs). Here we aimed to investigate, whether two cyclin-dependent kinase inhibitors, AZD5438 and R547, can interact with these pharmacokinetic mechanisms and reverse DAUN resistance. Using accumulation assays, we revealed AZD5438 as potent inhibitor of ABCC1 showing also weaker inhibitory effect to ABCB1 and ABCG2. Combination index analysis, however, shown that inhibition of ABCC1 does not significantly contribute to synergism between AZD5438 and DAUN in MDCKII-ABCC1 cells, suggesting predominant role of other mechanism. Using pure recombinant enzymes, we found both tested drugs to inhibit CREs with aldo-keto reductase 1C3 (AKR1C3). This interaction was further confirmed in transfected HCT-116 cells. Moreover, these cells were sensitized to DAUN by both compounds as Chou-Talalay combination index analysis showed synergism in AKR1C3 transfected HCT-116, but not in empty vector transfected control cell line. In conclusion, we propose AZD5438 and R547 as modulators of DAUN resistance that can prevent AKR1C3-mediated DAUN biotransformation to DAUN-OL. This interaction could be beneficially exploited to prevent failure of DAUN-based therapy as well as the undesirable cardiotoxic effect of DAUN-OL., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Buparlisib is a pan-class I phosphoinositide 3-kinase (PI3K) inhibitor and is currently under clinical evaluation for the treatment of different cancers. Because PI3K signalling is related to cell proliferation and resistance to chemotherapy, new therapeutic approaches are focused on combining PI3K inhibitors with other anti-cancer therapeutics. Carbonyl-reducing enzymes catalyse metabolic detoxification of anthracyclines and reduce their cytotoxicity. In the present work, the effects of buparlisib were tested on six human recombinant carbonyl-reducing enzymes: AKR1A1, AKR1B1, AKR1B10, AKR1C3, and AKR7A2 from the aldo-keto reductase superfamily and CBR1 from the short-chain dehydrogenase/reductase superfamily, all of which participate in the metabolism of daunorubicin. Buparlisib exhibited the strongest inhibitory effect on recombinant AKR1C3, with a half-maximal inhibitory concentration (IC 50 ) of 9.5 μM. Its inhibition constant K i was found to be 14.0 μM, and the inhibition data best fitted a mixed-type mode with α = 0.6. The same extent of inhibition was observed at the cellular level in the human colorectal carcinoma HCT 116 cell line transfected with a plasmid encoding the AKR1C3 transcript (IC 50  = 7.9 μM). Furthermore, we performed an analysis of flexible docking between buparlisib and AKR1C3 and found that buparlisib probably occupies a part of the binding site for a cofactor most likely via the trifluoromethyl group of buparlisib interacting with catalytic residue Tyr55. In conclusion, our results show a novel PI3K-independent effect of buparlisib that may improve therapeutic efficacy and safety of daunorubicin by preventing its metabolism by AKR1C3., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Mitochondrial electron transport chain (ETC) targeting shows a great promise in cancer therapy. It is particularly effective in tumors with high ETC activity where ETC-derived reactive oxygen species (ROS) are efficiently induced. Why modern ETC-targeted compounds are tolerated on the organismal level remains unclear. As most somatic cells are in non-proliferative state, the features associated with the ETC in quiescence could account for some of the specificity observed. Here we report that quiescent cells, despite increased utilization of the ETC and enhanced supercomplex assembly, are less susceptible to cell death induced by ETC disruption when glucose is not limiting. Mechanistically, this is mediated by the increased detoxification of ETC-derived ROS by mitochondrial antioxidant defense, principally by the superoxide dismutase 2 - thioredoxin axis. In contrast, under conditions of glucose limitation, cell death is induced preferentially in quiescent cells and is correlated with intracellular ATP depletion but not with ROS. This is related to the inability of quiescent cells to compensate for the lost mitochondrial ATP production by the upregulation of glucose uptake. Hence, elevated ROS, not the loss of mitochondrially-generated ATP, are responsible for cell death induction by ETC disruption in ample nutrients condition, e.g. in well perfused healthy tissues, where antioxidant defense imparts specificity. However, in conditions of limited glucose, e.g. in poorly perfused tumors, ETC disruption causes rapid depletion of cellular ATP, optimizing impact towards tumor-associated dormant cells. In summary, we propose that antioxidant defense in quiescent cells is aided by local glucose limitations to ensure selectivity of ETC inhibition-induced cell death., (Copyright © 2017 Elsevier Inc. All rights reserved.)

AKR1B10 is an NADPH-dependent reductase that plays an important function in several physiological reactions such as the conversion of retinal to retinol, reduction of isoprenyl aldehydes, and biotransformation of procarcinogens and drugs. A growing body of evidence points to the important role of the enzyme in the development of several types of cancer (e.g., breast, hepatocellular), in which it is highly overexpressed. AKR1B10 is regarded as a therapeutic target for the treatment of these diseases, and potent and specific inhibitors may be promising therapeutic agents. Several inhibitors of AKR1B10 have been described, but the area of natural plant products has been investigated sparingly. In the present study almost 40 diverse phenolic compounds and alkaloids were examined for their ability to inhibit the recombinant AKR1B10 enzyme. The most potent inhibitors-apigenin, luteolin, and 7-hydroxyflavone-were further characterized in terms of IC50, selectivity, and mode of action. Molecular docking studies were also conducted, which identified putative binding residues important for the interaction. In addition, cellular studies demonstrated a significant inhibition of the AKR1B10-mediated reduction of daunorubicin in intact cells by these inhibitors without a considerable cytotoxic effect. Although these compounds are moderately potent and selective inhibitors of AKR1B10, they constitute a new structural type of AKR1B10 inhibitor and may serve as a template for the development of better inhibitors.

Pharmacokinetic drug resistance is a serious obstacle that emerges during cancer chemotherapy. In this study, we investigated the possible role of aldo-keto reductase 1C3 (AKR1C3) in the resistance of cancer cells to anthracyclines. First, the reducing activity of AKR1C3 toward anthracyclines was tested using incubations with a purified recombinant enzyme. Furthermore, the intracellular reduction of daunorubicin and idarubicin was examined by employing the transfection of A549, HeLa, MCF7 and HCT 116 cancer cells with an AKR1C3 encoding vector. To investigate the participation of AKR1C3 in anthracycline resistance, we conducted MTT cytotoxicity assays with these cells, and observed that AKR1C3 significantly contributes to the resistance of cancer cells to daunorubicin and idarubicin, whereas this resistance was reversible by the simultaneous administration of 2'-hydroxyflavanone, a specific AKR1C3 inhibitor. In the final part of our work, we tracked the changes in AKR1C3 expression after anthracycline exposure. Interestingly, a reciprocal correlation between the extent of induction and endogenous levels of AKR1C3 was recorded in particular cell lines. Therefore, we suggest that the induction of AKR1C3 following exposure to daunorubicin and idarubicin, which seems to be dependent on endogenous AKR1C3 expression, eventually might potentiate an intrinsic resistance given by the normal expression of AKR1C3. In conclusion, our data suggest a substantial impact of AKR1C3 on the metabolism of daunorubicin and idarubicin, which affects their pharmacokinetic and pharmacodynamic behavior. In addition, we demonstrate that the reduction of daunorubicin and idarubicin, which is catalyzed by AKR1C3, contributes to the resistance of cancer cells to anthracycline treatment., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Ochratoxin A (OTA) is nephrotoxic, hepatotoxic, reprotoxic, embryotoxic, teratogenic, neurotoxic, immunotoxic, and carcinogenic for laboratory and farm animals. Male and female reproductive health has deteriorated in many countries during the last few decades. A number of toxins in environment are suspected to affect reproductive system in male and female. OTA is one of them. OTA has been found to be teratogenic in several animal models including rat, mouse, hamster, quail, and chick, with reduced birth weight and craniofacial abnormalities being the most common signs. The presence of OTA also results in congenital defects in the fetus. Neither the potential of OTA to cause malformations in human nor its teratogenic mode of action is known. Exposure to OTA leads to increased embryo lethality manifested as resorptions or dead fetuses. The mechanism of OTA transfer across human placenta (e.g., which transporters are involved in the transfer mechanism) is not fully understood. Some of the toxic effects of OTA are potentiated by other mycotoxins or other contaminants. Therefore, OTA exposure of pregnant women should be minimized. OTA has been shown to be an endocrine disruptor and a reproductive toxicant, with abilities of altering sperm quality. Other studies have shown that OTA is a testicular toxin in animals. Thus, OTA is a biologically plausible cause of testicular cancer in man., (© 2014 Wiley Periodicals, Inc.)

Background: The mechanism of IgA nephropathy (IgAN) progression remains ill-defined. In this prospective study, the prognostic role of clinical, histological and molecular markers over a 2-year follow-up was evaluated., Methods: Fifty-one patients with biopsy-proven IgAN were followed for 24 months. Besides routine histology, the intrarenal gene expressions of cytokines and chemokines were quantified by reverse transcription quantitative real-time polymerase chain reaction, and the presence of lymphocytes and macrophages were immunohistochemically examined., Results: Higher transforming growth factor-β1 and severe chronic vasculopathy (but not glomerulosclerosis, interstitial fibrosis or lymphocyte infiltrate) were associated with the IgAN progression 24 months after biopsy. The gene expression of chemokine (C-C motif) ligands 2 and 5, hepatocyte growth factor, bone morphogenic protein-7 and transforming growth factor-β1 and the interstitial infiltrate of T and B lymphocytes and macrophages were significantly associated with serum creatinine and glomerular filtration rate at the time of biopsy. The intrarenal chemokine (C-C motif) ligand 2 and hepatocyte growth factor gene expression were associated with the proteinuria., Conclusions: Besides the known risk factors for chronic kidney disease, advanced vasculopathy and molecular signatures of fibrogenesis were associated with the IgAN progression.

Background: Bioavailability of tacrolimus (Tac) and cyclosporine is determined by cytochrome P450IIIA and by P-glycoprotein encoded by the CYP3A4/CYP3A5 and ABCB1 genes. Polymorphisms in these genes have been suggested to influence acute rejection and pharmacokinetics in renal transplantation. We aimed to validate these findings in a haplotype analysis., Methods: A total of 832 renal transplant recipients were genotyped for the CYP3A4 -288A>G, CYP3A5 +6986G>A, ABCB1 +1236C>T, +2677G>T>A, and +3435C>T polymorphisms. Their association with acute rejection and with pharmacokinetic parameters was analyzed in haplotype models., Results: Apart from human leukocyte antigen-DR mismatches, delayed graft function and age at renal transplantation, acute rejection was also predicted by the [ABCB1 +1236C; +2677G; +3435T] haplotype. Allograft survival was determined by donor age, age at renal transplantation, delayed graft function, cold ischemia, and history of more than two acute rejections. Homozygotes for the [CYP3A4 -288A; CYP3A5 +6986G] haplotype achieved earlier therapeutic concentrations of Tac and a higher concentration to dose ratio at week 1. ABCB1 haplotypes did not influence pharmacokinetic parameters., Conclusions: ABCB1 haplotypes modify the risk of acute rejection, suggesting that ABCB1 allelic arrangement is a stronger regulator of P-glycoprotein activity than single polymorphisms. The risk of acute rejection determined by ABCB1 is independent of pharmacokinetic parameters. CYP3A haplotypes control the bioavailability of Tac, but do not modify the risk of acute rejection.

Introduction: The early phase of essential hypertension has been associated with changes in cardiovascular regulation caused by imbalance in some parts of autonomic nervous system. Autonomic effect of various stimuli on haemodynamic variables is usually tested by changes in blood pressure (BP) and/or heart rate (HR). It is known that increased sympathetic drive of ventricles can interfere with repolarization process., The Aim: This study was focused on reactive changes of maximal spatial T vector (sTmax) and R-R intervals, in relation to BP changes in 79 boys and men, averaged age 17 +/- 2 yrs. 36 from them where adolescents with elevated BP (high normal or hypertension I according to WHO/ISH1999) (EBP), 19 normotensives (NBP), and 24 normotensive sportsmen. R-R intervals and maximal spatial T vector were recorded by a PC (Cardiag METE, Prague) with Frank lead system while sitting in mid-respiratory position, during mental arithmetic (MA) and during passive head-up tilting to 60 degrees. BP was measured simultaneously by a cuff sphygmomanometer, using phases 1 and 5 of Korotkoff sounds., Results: MA resulted in significant BP increase in all subgroups, however the reactive changes of systolic BP as well as magnitude of R-R shortening, and sTmax decline were about two times higher in sportsmen. Head-up tilting evoked in all subgroups a significant increase of diastolic BP that was again higher in sportsmen vs. EBP and NBP. R-R interval became significantly (p < 0.02) and more often shortened in sportsmen than in EBP and NBP. Relatively more evident decline of sTmax (more than 20%) in EBP was the highest change from all observed parameters to both tested stimuli., Conclusion: Our results indicate that for analysis of the effect of stimuli, which modulate balance in autonomic nervous system, it is helpful to pay attention also to the parameters of repolarization process that may represent a sensitive indicator of sympathetic tonization in myocardial ventricles. (Tab. 4, Fig. 2, Ref. 27.)

The exercise load in karate is prevailingly of anaerobic character, the fact of which is evident by the increase in heart frequency and the levels of blood lactate. During competition, the heart frequency achieved the values of 180-199 beats per minute and the level of blood lactate following the competition was 4.5-6.5 mmol/l. The values of lactate were substantially higher during the training unit (at the time of chronometric measurement) when exercise was more intensive 5.8-12.5 mmo/l at the heart frequency of 180-200 or even more beats per minute, than during competition. The aim of this work was to find out the basic morphologic and functional profiles in the representatives of the National Karate Team on the basis of laboratory methods.