Anticonvulsant and reproductive toxicological studies of the imidazole-based histamine H3R antagonist 2-18 in mice

The imidazole-based H3R antagonist 2-18 with high in vitro H3R antagonist affinity, excellent in vitro selectivity profile, and high in vivo H3R antagonist potency was tested for its anticonvulsant effect in maximal electroshock (MES)-induced convulsions in mice having valproic acid (VPA) as a reference antiepileptic drug (AED). Additionally, H3R antagonist 2-18 was evaluated for its reproductive toxicity in the same animal species. The results show that acute systemic administration (intraperitoneal; i.p.) of H3R antagonist 2-18 (7.5, 15, 30, and 60 mg/kg, i.p.) significantly and dose dependently protected male as well as female mice against MES-induced convulsion. The protective action observed for H3R antagonist 2-18 in both mice sexes was comparable to that of VPA and was reversed when mice were pretreated with the selective H3R agonist (R)-alpha-methylhistamine (RAMH, 10 mg/kg, i.p.). Moreover, the results show that acute systemic administration of single (7.5, 15, 30, or 60 mg/kg, i.p.) or multiple doses (15×3 mg/kg, i.p.) of H3R antagonist 2-18 on gestation day (GD) 8 or 13 did not affect the maternal body weight of mice when compared with the control group. Furthermore, no significant differences were observed in the average number of implantations and resorptions between the control and H3R antagonist 2-18-treated group at the early stages of gestation and the organogenesis period. However, oral treatment with H3R antagonist 2-18 (15 mg/kg) on GD 8 induced a reduced number of live embryos when compared with the i.p.-treated mice. In addition, no significant changes in the fetal body and placental weights were observed after injection of H3R antagonist 2-18 with all selected doses. However, three dose groups of i.p. and oral 15 mg/kg on GD 13 significantly affected the placental weight when compared with control group. Notably, the treatment of pregnant female with the H3R antagonist 2-18 did not produce significant malformation in the fetus in both groups. In conclusion, the novel H3R antagonist 2-18 proves to be a very safe compound and displays a low incidence of malformations, demonstrating that H3R antagonist 2-18 may have a potential future therapeutic value in epilepsy

Aryl-1,3,5-triazine ligands of histamine H4H_{4} receptor attenuate inflammatory and nociceptive response to carrageen, zymosan and lipopolysaccharide

Objective and design Histamine $H_{4}$ receptor ($H_{4}R$) offers a great potential for new therapeutic strategies for the treatment of inflammation-based diseases. The aim of this study is to present the pharmacological profile of two recently synthesized ligands of $H_{4}R$ with particular reference to their anti-inflammatory and analgesic activity. Materials and subjects We used mice and rats in the in vivo tests. We also used murine RAW 264.7 cells and isolated guinea-pig ileum in in vitro test. Treatments In the in vivo tests, animals were pre-treated with the increasing doses of investigated compounds (12.5, 25 and 50 mg/kg) and reference compounds: JNJ7777120 (25 mg/kg), indomethacin (10 mg/kg). Macrophages were pre-treated with two concentrations of tested compounds 100 and 10 $\mu$M. Methods We examined anti-inflammatory and analgesic effects of the new $H_{4}R$ antagonists in the in vivo models of inflammation induced by carrageenan or zymosan. We assessed the level of cAMP and release of cytokines, ROS and NO in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Moreover, we assessed the affinity of the investigated compounds for histamine $H_{1}$ receptor in functional studies. Results Both investigated compounds reduced paw edema, mechanical and thermal hyperalgesia in the carrageenaninduced acute inflammation. Moreover, administration of the investigated compounds resulted in decreased granulocyte influx and attenuated nociceptive reaction in the zymosan-induced peritonitis model. In the same model of inflammation, the investigated compounds reduced vascular permeability; however, this effect was observed only after the highest applied dose. Furthermore, the test compounds had no impact on cell viability in the experiments on RAW 264.7 macrophages. In these cells, stimulated with LPS, the test compounds decreased reactive oxygen species (ROS) production. They increased the cellular concentration of cAMP and attenuated the production of inflammatory cytokines such as $TNF\alpha$ and $IL-1\beta$. All results were comparable to those obtained for the reference compound JNJ7777120 with the exception of the impact on NO production. Nevertheless, this effect was similar to that obtained for the other reference compound rolipram, which is a phosphodiesterase 4 (PDE 4) inhibitor. Further experiments revealed that both of the investigated compounds possessed relatively low affinity for histamine H$_{1}$ receptor and do not inhibit the activity of the PDE 4B1 enzyme. In addition, all the effects of the investigated compounds in in vivo experiments were observed at doses that did not cause neurologic deficits in rotarod test and did not reduce spontaneous locomotor activity. Conclusions Our results demonstrate the anti-inflammatory and analgesic activity of the new aryl-1,3,5-triazine derivatives, which are primarily $H_{4}R$-dependent

Drug-induced liver injury (DILI) - mechanisms and diagnostic

The drug-induced liver injury (DILI) is one of the leading causes of the liver disease in developed countries. These injuries may be the result of constant drug hepatotoxicity or idiosyncrasy associated with the drug or its metabolite. The constant hepatotoxicity of a drug is related to its mechanism of action, so it is predictable and dose-dependent (the classic example that causes the greatest amount of the liver damage in Western countries is paracetamol). Idiosyncratic reactions are difficult to predict and occur rarely, which makes them very harmful. As the liver is not only an important gland in the digestive system, but also one of the most important organs for the body, its damage causes a large number of complications with often very serious consequences. The diagnosis of the drug-induced liver injury is independent of the cause of the liver injury and is based on a relatively small number of available laboratory tests. Currently, the "gold standard" in predicting severe drug-induced liver injury is Hy's law, that is, comparing ALT activity and bilirubin concentration in the presence of a jaundice. Improving the detection efficiency of DILI is necessary both for the safety of patients at a risk of the liver injury and for the development of methods for assessing potential hepatotoxicity of drugs during the research phase. Among the new potential DILI biomarkers we can distinguish glutamate dehydrogenase, HMGB1 protein (High-Mobility Group Box-1) as well as keratin-18 (K18) and microRNA-122 (miR-122). Despite the growing awareness of the toxicity of certain drugs, the drug-induced liver injury is still a very serious problem in the Western world. This demonstrates the need to continuously educate people about the possible side effects of their medications and dietary supplements. An accurate diagnosis of DILI requires establishing a causal relationship with the suspected factor and excluding other possible causes of the liver damage. Administration of drugs causing idiosyncratic liver damage should take place under the strict control of the liver markers so as to react as quickly as possible in the event of an idiosyncratic reaction. Further research on new biomarkers is needed, so that their potential introduction as the DILI diagnostic standard is supported by the best scientific evidence and allows for a reliable diagnosis

Virulence factors of Enterococcus strains isolated from patients with inflammatory bowel disease

AIM: To determine the features of Enterococcus that contribute to the development and maintenance of the inflammatory process in patients with inflammatory bowel disease (IBD). METHODS: Multiplex polymerase chain reaction (PCR) was applied to assess the presence of genes that encode virulence factors [surface aggregating protein (asa1), gelatinase (gelE), cytolysin (cylA), extracellular surface protein (esp) and hyaluronidase (hyl)] in the genomic DNA of 28 strains of Enterococcus isolated from the intestinal tissues of children with IBD (n = 16) and of children without IBD (controls; n = 12). Additionally, strains with confirmed presence of the gelE gene were tested by PCR for the presence of quorum sensing genes (fsrA, fsrB, fsrC) that control the gelatinase production. Gelatinase activity was tested on agar plates containing 1.6% gelatin. We also analysed the ability of Enterococcus strains to release and decompose hydrogen peroxide (using Analytical Merckoquant peroxide test strips) and tested their ability to adhere to Caco-2 human gut epithelium cells and form biofilms in vitro. RESULTS: A comparison of the genomes of Enterococcus strains isolated from the inflamed mucosa of patients with IBD with those of the control group showed statistically significant differences in the frequency of the asa1 gene and the gelE gene. Furthermore, the cumulative occurrence of different virulence genes in the genome of a single strain of Enterococcus isolated from the IBD patient group is greater than in a strain from the control group, although no significant difference was found. Statistically significant differences in the decomposition of hydrogen peroxide and adherence to the Caco-2 epithelial cell line between the strains from the patient group and control group were demonstrated. The results also showed that profuse biofilm production was more frequent among Enterococcus strains isolated from children with IBD than in control strains. CONCLUSION: Enterococcus strains that adhere strongly to the intestinal epithelium, form biofilms and possess antioxidant defence mechanisms seem to have the greatest influence on the inflammatory process

Secondary prevention of stroke in elderly people in Poland—Results of PolSenior study

Background and purpose The purpose of the study was to evaluate the frequency of use of oral antiplatelet (OAP) and anticoagulant (OAC) drugs as secondary stroke prevention among older people in Poland and its association with sociodemographic factors, place of residence, and concomitant cardiovascular risk factors. Material and methods The study group consisted of 426 subjects with a history of a previous stroke (mean age of 81.5±8.2 years), participants of multicentre, population-based PolSenior study. Results Among the study group, 261 people (61.3%) used at least one drug as a secondary prevention. OAPs were regularly used by 237 people (55.6%), and OACs—by 25 people (5.9%). The most often used drug was acetylsalicylic acid. Ticlopidine was more frequently used than clopidogrel, and acenocoumarol was used more often than warfarin. Among all of the concomitant cardiovascular risk factors, congestive heart failure was mostly associated with OAP treatment, and a history of atrial fibrillation—with OAC treatment. Use of drugs did not depend on age, sex, place of residence (rural or urban), level of education and personal income, but it was associated with the region where the respondents lived. Conclusions Secondary cardiovascular preventive therapy in Poland is used too rarely in older people after stroke, and it especially concerns anticoagulant therapy in those with a history of atrial fibrillation. Structured educational programmes should be developed in Poland to improve usage of secondary preventive therapy in the elderly

The 1,3,5-triazine derivatives as innovative chemical family of 5-HT6 serotonin receptor agents with therapeutic perspectives for cognitive impairment

Among serotonin receptors, the 5-HT6 subtype is the most controversial and the least known in the field of molecular mechanisms. The 5-HT6R ligands can be pivotal for innovative treatment of cognitive impairment, but none has reached pharmacological market, predominantly, due to insufficient “druglikeness” properties. Recently, 1,3,5-triazine-piperazine derivatives were identified as a new chemical family of potent 5-HT6R ligands. For the most active triazine 5-HT6R agents found (1-4), a wider binding profile and comprehensive in vitro evaluation of their drug-like parameters as well as behavioral studies and an influence on body mass in vivo were investigated within this work. Results indicated the most promising pharmacological/druglikeness profiles for 4-((1H-indol-3-yl)methyl)-6-(4-methylpiperazin-1-yl)-1,3,5-triazin-2-amine (3) and 4-((2-isopropyl-5-methylphenoxy)methyl)-6-(4-methylpiperazin-1-yl)-1,3,5-triazin-2-amine (4), which displayed a significant procognitive action and specific anxiolytic-like effects in the behavioral tests in vivo together with satisfied pharmaceutical and safety profiles in vitro. The thymol derivative (4) seems to be of higher importance as a new lead candidate, due to the innovative, non-indole and non-sulfone structure with the best 5-HT6R binding properties

Pharmacological stroke prevention in the elderly with atrial fibrillation in Poland : results of PolSenior study

Introduction: Atrial fibrillation (AF) is the most frequent clinically significant arrhythmia, especially common in the elderly. As it is known, AF is associated with increased risk of stroke. Little is known about pharmacological cardiovascular prevention in the elderly with AF in Poland. Objectives: The purpose of the study was to evaluate the frequency of pharmacological stroke prevention among the elderly with AF in Poland and its association with clinical characteristics and concomitant cardiovascular risk factors. Patients and methods: The analysis included elderly (≥65 years) participants of the PolSenior study performed in years 2008-2012. Results: The study group consisted of 4979 people (mean age: 79.3 8.7 years). Among them, there were 875 patients (18.7%) with documented history of AF. Pharmacological prevention with the use of vitamin K antagonists (VKA) was applied by 117 (13.4%) of the elderly with AF, including 15 (1.7%) on dual therapy. Additionally, 386 (45.3%) subjects with AF were using oral antiplatelet therapy (OAPs), mostly aspirin. Acenocoumarol was much more often used than warfarin. New oral anticoagulant drugs (NOACs) were not used at all. Only personal income was associated with the use of VKA. No significant correlation was found for the age, sex, place of residence and level of education