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Introduction: Although pharmacogenetics and pharmacogenomics have been at the forefront of research aimed at finding novel personalized therapies, the focus of research has recently extended to the potential of intestinal microbiota to affect drug efficacy. Complex interplay of gut microbiota with bile acids may have significant repercussions on drug pharmacokinetics. However, far too little attention has been paid to the potential implication of gut microbiota and bile acids in simvastatin response which is characterized by large interindividual variations.The Aim: In order to gain more insight into the underlying mechanism and its contribution in assessing the clinical outcome, the aim of our study was to examine simvastatin bioaccumulation and biotransformation in probiotic bacteria and the effect of bile acids on simvastatin bioaccumulation in in vitro conditions.Materials and methods: Samples with simvastatin, probiotic bacteria and three different bile acids were incubated at anaerobic conditions at 37°C for 24 h. Extracellular and intracellular medium samples were collected and prepared for the LC-MS analysis at predetermined time points (0 min, 15 min, 1 h, 2 h, 4 h, 6 h, 24 h). The concentrations of simvastatin were analyzed by LC-MS/MS. Potential biotransformation pathways were analyzed using a bioinformatics approach in correlation with experimental assay.Results: During the incubation, simvastatin was transported into bacteria cells leading to a drug bioaccumulation over the time, which was augmented upon addition of bile acids after 24 h. A decrease of total drug level during the incubation indicates that the drug is partly biotransformed by bacterial enzymes. According to the results of bioinformatics analysis, the lactone ring is the most susceptible to metabolic changes and the most likely reactions include ester hydrolysis followed by hydroxylation.Conclusion: Results of our study reveal that bioaccumulation and biotransformation of simvastatin by intestinal bacteria might be the underlying mechanisms of altered simvastatin bioavailability and therapeutic effect. Since this study is based only on selected bacterial strains in vitro, further more in-depth research is needed in order to elicit completely the contribution of complex drug-microbiota-bile acids interactions to overall clinical response of simvastatin which could ultimately lead to novel approaches for the personalized lipid-lowering therapy.

Despite a relatively low prevalence of primary brain tumors, they continuously attract scientific interest because of the complexity of their treatment due to their location behind the blood-brain barrier. The main challenge in treatment of brain tumors is not the efficacy of the drugs, per se, but the low efficiency of drug delivery to malignant cells. At the core of the problem is the complex structure of the blood-brain barrier. Nowadays, there is evidence supporting the claim that bile acids have the ability to cross the blood-brain barrier. That ability can be exploited by taking a part in novel drug carrier designs. Bile acids represent a drug carrier system as a part of a mixed micelle composition, bilosomes and conjugates with various drugs. This review discusses the current knowledge related to bile acid molecules as drug penetration modifying agents, with the focus on central nervous system antitumor drug delivery.

Since its discovery in 1945, methotrexate has become a standard therapy for number of diseases, including oncological, inflammatory and pulmonary ones. Major physiological interactions of methotrexate include folate pathway, adenosine, prostaglandins, leukotrienes and cytokines. Methotrexate is used in treatment of pulmonary sarcoidosis as a second line therapy and is drug of choice in patients who are not candidates for corticosteroid therapy, with recommended starting weekly dose of 5-15 mg. Number of studies dealt with methotrexate use in rheumatoid arthritis and oncological patients. Authors are conducting research on oral methotrexate use and pharmacokinetics in chronic sarcoidosis patients and have performed literature research to better understand molecular mechanisms of methotrexate action as well as high level pharmacokinetic considerations. Polyglutamation of methotrexate affects its pharmacokinetic and pharmacodynamic properties and prolongs its effect. Bile excretion plays significant role due to extensive enterohepatic recirculation, although majority of methotrexate is excreted through urine. Better understanding of its pharmacokinetic properties in sarcoidosis patients warrant optimizing therapy when corticosteroids are contraindicated in these patients.

High-dose methotrexate (HD-MTX) is the mainstream therapy of current acute lymphoblastic leukemia (ALL) regimens, but frequent intra- and interindividual differences in the clinical response to HD-MTX lead to chemotherapeutic interruption or discontinuation. The exact mechanism of transport across the cell membrane and the disposition of active methotrexate metabolites—methotrexate polyglutamates (MTXPGs)—are not well described in the literature. The aim of this study was to gain more insight into the plasma distribution of methotrexate and MTXPGs in pediatric patients with ALL and to clarify the obscure pathways of MTXPGs. We prospectively measured the concentrations of MTXPG1–7 in plasma samples from three male pediatric patients treated with HD-MTX and leucovorin rescue according to the IC-BFM 2009 protocol using liquid chromatography–mass spectrometry (LC-MS). Blood samples were obtained at 24, 36, 42, and 48 h after the start of HD-MTX treatment. Noticeable plasma concentrations of MTXPGs with a 2.2-fold interpatient variability were detected. The highest interindividual variability in total plasma MTXPG concentration was observed at 36 h, and ranged from 13.78 to 30.82 μmol/L. Among all patients, the predominant polyglutamate types in relation to the total plasma MTXPG concentration at each time point were MTXPG3 (16.71–30.02%) and MTXPG5 (26.23–38.60%), while MTXPG7 was the least abundant MTXPG (3.22–5.02%). The presence of MTXPGs in plasma of patients with ALL could be related to the action of ABC efflux transporters on blood cells and hepatocytes resulting from the administration of high doses of methotrexate. This study may not draw definitive conclusions, but it does reduce uncertainty about the dynamics of methotrexate and its active metabolites, which may be of vital importance for achieving a clinical response.

Gliclazide is a drug commonly used in type 2 diabetes mellitus. Recently, gliclazide has shown desirable pharmacological effects such as immunoregulatory and anti-clotting effects, which suggests potential applications in type 1 diabetes mellitus (T1DM). Gliclazide has variable absorption after oral administration, and thus using targeted-delivery techniques, such as microencapsulation, may optimise gliclazide absorption and potential applications in T1DM. Bile acids such as cholic acid have shown microcapsule-stabilising and controlled-release effects, and thus their incorporation into gliclazide microcapsules may further optimise gliclazide release, absorption and antidiabetic effects. Accordingly, this study aimed to examine the hypoglycaemic effects of gliclazide microcapsules with and without cholic acid, in a rat model of T1DM. Thirty-five alloxan-induced T1DM rats were randomly divided into five equal groups and gavaged a single dose of empty microcapsules, gliclazide, gliclazide microcapsules, gliclazide-cholic acid or gliclazide-cholic acid microcapsules. Blood samples were collected over 10 h post-dose and analysed for blood glucose and gliclazide serum concentrations. Gliclazide microcapsules exerted a hypoglycaemic effect in the diabetic rats, and cholic acid incorporation diminished the hypoglycaemic effects, which suggests the lack of synergistic effects between gliclazide and cholic acid. In addition, neither microencapsulation nor cholic acid incorporation optimised gliclazide absorption which suggests that hypoglycaemic effects of gliclazide are independent of its absorption and serum concentrations. This also suggests that hypoglycaemic effects of gliclazide may be associated with gut-metabolic activation rather than gut-targeted delivery and systemic absorption. Gliclazide microcapsules exerted hypoglycaemic effects in T1DM rats independent of insulin and thus may have potentials in treatment of T1DM.

Background/Aim: Gliclazide is one of the most commonly prescribed oral anti-hyperglycaemic therapies in type 2 diabetes mellitus (T2D). Recently reported additional beneficial pharmacological properties of gliclazide, including immunomodulatory and anticoagulant activities, suggested its potential application in treatment of type 1 diabetes mellitus (T1D). However, following oral administration, gliclazide was shown to have poor and variable absorption directing research into development of novel pharmaceutical delivery systems of gliclazide suitable for T1D. Since bile acids have previously demonstrated stabilising and controlled-release effects on microcapsules, their use for preparation of microcapsules of gliclazide may lead to improvements in gliclazide release, absorption and antidiabetic effects. This investigation was aimed to evaluate drug absorption profiles and hypoglycaemic effects of alginate-based microcapsules of gliclazide, prepared together with or without cholic acid, in healthy rats. Methods: Thirty healthy Wistar rats with confirmed normal glucose blood concentration were allocated into five groups and administered with a single dose of either vehicle microcapsules, gliclazide in suspension, gliclazide microcapsules, gliclazide in suspension together with cholic acid or microencapsulated gliclazide in combination with cholic acid. Following respective gliclazide dose, blood was sampled over next 10 hours and blood glucose levels and gliclazide serum concentrations were measured. Results: This analysis demonstrated altered effects of different gliclazide formulations in healthy rats with the highest gliclazide absorption mirrored by the most profound hypoglycaemic effect being achieved after its oral administration as a suspension (p

Introduction: Inter-individual differences in gut microflora composition may affect drug metabolism and overall therapeutic response. Gliclazide is a drug characterized by large inter-individual differences in therapeutic response; however, the causes of these differences are not fully explained and may be the outcome of microbial biotransformation. Recently, great attention has been paid to studies on bile acid (BA) interactions with gut microflora and the role of BAs in the modification of drug transport through biological membranes. The Aim: Considering the assumption of gliclazide-probiotic-BAs interactions, the aim of the study was to investigate the transport and biotransformation of gliclazide in probiotic bacteria, as well as the effects of deoxycholic acid (DCA) on gliclazide transport into bacterial cells. Materials and Methods: Probiotics were incubated with gliclazide with or without DCA for 24 h at 37°C. The intracellular and extracellular concentrations of gliclazide were determined at seven time points by high-performance liquid chromatography. Gliclazide biotransformation by the enzymatic activity of probiotic bacteria was examined using appropriate software packages. Results: During the 24 h incubation with probiotic bacteria, significantly lower extracellular concentrations of gliclazide were observed at all time points compared to controls, while in the group with DCA, the decrease in concentration was noticed only at 24 h. The total concentration of gliclazide throughout the whole period was significantly lower compared to control. Proposed pathways of gliclazide biotransformation by probiotic bacteria involve reactions of hydrolysis and hydroxylation. Conclusion: Based on the results obtained, it can be concluded that there are interactions of gliclazide-probiotics-DCA, at both the level of active and passive transport into the cells, and at the level of drug biotransformation by enzymatic activity of probiotic bacteria. The effect of these interactions on the final therapeutic response of gliclazide should be further studied and confirmed in in vivo conditions.

Introduction: Rosemary essential oil can be used for treating dyspepsia, mild spasmodic disorders of thegastrointestinal tract, externally as analgetic in muscular and articular pain and minor peripheral circulatory disorders.It is important to explore its analgesic potential and its influence on the pharmacodynamic and pharmacokineticproperties of paracetamol. Methodology: Rosemary essential oil was applied to mice orally (doses: 10 and 20 mg/kgb.w.) for pharmacodynamic tests for seven days. Rats treated with rosemary essential oil for seven days orally (5 and10 mg/kg b.w.) were used for the examination of the influence of essential oil on the pharmacokinetic properties ofparacetamol (applied on the 7th day p.o. or i.v.). Pharmacokinetic parameters were analyzed in blood samples obtainedfrom rats' tail veins, with the HPLC method. Results: The essential oil of rosemary shows analgetic properties. Therosemary essential oil increases pharmacological effects of paracetamol and does not change paracetamolbioavailability. Conclusion: The herbal drugs could change the pharmacodynamic and the pharmacokinetic propertiesof classical drugs and they could also change the safety of classical drugs use in human population.

Aniseed (Pimpinella anisum L., Apiaceae) and its essential oil (EO) have been widely used. Because there are some data about the impact of aniseed EO on drug effects, this survey aimed to assess the potential of pharmacokinetic herb-drug interaction between aniseed EO and acetaminophen and caffeine in mice. The chemical analysis (gas chromatography-mass spectrometry) of aniseed EO has confirmed trans-anethole (87.96%) as the main component. The pharmacokinetic studies of intraperitoneally (i.p.) and orally applied acetaminophen (200 mg/kg) and caffeine (20 mg/kg) were performed in mice after 5 days of oral treatment with human equivalent dose of aniseed EO (0.3 mg/kg/day). The analysis of pharmacokinetic data showed that in the group treated by aniseed EO, the significant decrease in the peak plasma concentration of acetaminophen after oral application (p = 0.024) was revealed when compared with control group and the reduction of systemic exposure to the drug after oral application (74 ± 32% vs. 85 ± 35% in the control) was noted. The bioavailability of orally applied caffeine was also significantly decreased (p = 0.022) after the EO treatment in comparison with the control (57 ± 24% vs. 101 ± 29%). Therefore, the compromised therapeutic efficacy of acetaminophen and caffeine during the usage of aniseed EO preparations should be considered.

The aim is to evaluate the role of diazepam concentrations in development of low-concentration-methadone-associated QTc prolongation in patients with opioid use disorder during methadone maintenance treatment (MMT) induction.Individuals with addiction disorder on MMT were studied before the beginning of MMT and after one and six months of MMT. Serum concentrations of methadone, diazepam, electrolytes and ECG were analyzed.Thirty patients were enrolled. The mean methadone concentration at time points was 177 ± 119 ng/ml and 343 ± 182 ng/ml, while the mean diazepam concentration was 561 ± 437 ng/ml and 1045 ± 933 ng/ml. The QTc interval before the introduction of MMT, after 1 and 6 months of MMT were 412 ± 27 ms, 425 ± 18 ms and 424 ± 15 ms, respectively, showing statistically significant increase in the length of QTc interval after 1 and 6 months of MMT. Statistically significant correlation between the concentration of methadone and QTc interval length at observed time points (RThe prolongation of QTc below the risk threshold in low methadone therapeutic doses has been recorded and concomitant use of diazepam could be a co-factor in such issue.

Herb-drug interactions are an important safety concern and this study was conducted regarding the interaction between the natural top-selling antidepressant remedy Hypericum perforatum (Hypericaceae) and conventional drugs. This study examined the influence of acute pretreatment with different extracts of Hypericum perforatum from Serbia on pentobarbital-induced sleeping time, impairment of motor coordination caused by diazepam and paracetamol pharmacokinetics in mice. Ethanolic extract, aqueous extract, infusion, tablet and capsule of Hypericum perforatum were used in this experiment. The profile of Hypericum perforatum extracts as well as paracetamol plasma concentration was determined using RP-HPLC analysis. By quantitative HPLC analysis of active principles, it has been proven that Hypericum perforatum ethanolic extract has the largest content of naphtodianthrones: hypericin (57.77 µg/mL) and pseudohypericin (155.38 µg/mL). Pretreatment with ethanolic extract of Hypericum perforatum potentiated the hypnotic effect of pentobarbital and impairment of motor coordination caused by diazepam to the greatest extent and also increased paracetamol plasma concentration in comparison to the control group. These results were in correlation with naphtodianthrone concentrations. The obtained results have shown a considerable influence of Hypericum perforatum on pentobarbital and diazepam pharmacodynamics and paracetamol pharmacokinetics.

Background/Aim. It is known that bile acids improve the absorption, bioavailability and pharmacodynamic characteristics of some drugs. Morphine analgesia is produced by activation of opioid receptors within the central nervous system (CNS) at both spinal and supraspinal levels. Since a morphine molecule contains 3 polar groups and therefore hard to transfer through the blood-brain barrier, the aim of the study was to examine the potential influence of bile acids derivates, namely sodium salt of monoketocholic acid (MKH-Na) and methyl ester of monoketocholic acid (MKH-Me), on analgesic effect of morphine. Methods. White male mice of NMRI-Haan strain, with body weight of 20-24 g, were used in this study. The analgesic effect of morphine (administered by subcutaneous and intramuscular route in a dose of 2 mg/kg), with and without pretreatment with MKH-Na (4 mg/kg) and MKH-Me (4 mg/kg) was estimated by the hot plate method. Results. Administration of MKH-Me prior to subcutaneous administration of morphine increased the morphine analgesic effect but the increase was not statistically significant. At the same time administration of MKH-Na did not affect morphine analgesic effect. The analgesic effect of morphine increased when administered intramuscularly 20 min after MKH-Me administration. When compared with the group of animals treated only with morphine, a statistically significant increase in analgesic effect was detected 10, 30, 40 and 50 min after morphine administration (p < 0.05). Pretreatment with MKH-Na did not affect morphine analgesic effect. Conclusion. According to the results of this study it can be presumed that after intramuscular morphine administration methyl ester of monoketocholic acid increases morphine transport into the central nervous system and consequently the analgesic effect, as well. Further research on bile acids-morphine interaction both in vitro and in vivo is necessary to completely elucidate the mechanism of this interaction and increase in the morphine analgesic effect. [Projekat Ministarstva nauke Republike Srbije, br. 41012: Interactions of xenobiotics and the impact on biomedical system i br. 172050: Development and application of advanced chromatographic and spectroscopic techniques in analysing xenobiotics and the mechanisms of their decomposition in biotic and abiotic samples]

Aim: The aim of this study is to investigate the influence of bile salts, sodium cholate, sodium 12-ketocholate and sodium dehydrocholate, as excipients in ranitidine, aminophylline and phenobarbital tablets on dissolution rate. Methods: Four groups of tablets (control without bile salts and three investigational groups containing different bile salts) were prepared for three different drug substances: ranitidine, aminophylline and phenobarbital. Dissolution rate was measured. Results: Dissolution rate is increased significantly in all investigational groups comparing to the control group in all three drug substances. Discussion: Presented results are very favourable and encouraging in case of dissolution enhancing and should be further investigated, especially in drug substances that are classified in class II and IV as per Biopharmaceutical Classification System (BCS) classification. Conclusion: Bile acid salts are very promising excipients, proven to act as surfactants and as lubricants. Running title: Bile salts as excipients in ranitidine, aminophylline and phenobarbital tablets.

Diabetes mellitus is a chronic disease characterized by abnormal carbohydrate, lipid and protein metabolism due to a lack of insulin or reduced target cell sensitivity to insulin. Stevia rebaudiana is an important source of biochemically active substances with proven anti-diabetic effect. The aim of this study was to determine anti-diabetic effects of the low dose of stevioside in NMRI Haan mice. Aqueous stevioside solution (20mg/kg body weight) was administered by oral route of administration. Anti-diabetic effect of stevioside was estimated by oral glucose tolerance test, adrenaline test after a 10day stevioside treatment, and alloxan induced hyperglycaemia in mice (two experimental groups, 10day stevioside treatment before and after alloxan administration). Aqueous stevioside solution prevented significant increase in glycaemia in oral glucose tolerance test (9.22±1.13 to 9.85±1.32mmol/l, P

Purpose: Animal tests have been often used in toxicology to determine parameters describing toxicity of a particular substance. However, in vivo tests must fulfill ethical requirements, and are both time and money consuming. Therefore, computational methods are considered to be very useful in toxicity prediction. Methods: Retention parameters were acquired by normal-phase TLC. Lipophilicity was used as a key parameter for predicting toxic potential. The correlation coefficients between calculated log P values obtained by five different software and experimentally determined hydrophobicity parameters ((tol/et), (tol/but), b(tol/et) and b(tol/but)) were calculated. Results: Correlation analysis provided reliable information (r2 > 0,8) for aquatic species – minnow, medaka, daphnia, and algae. In addition valuable data regarding rodents and AMES test were obtained. Conclusions: Tested bile acids show relatively good toxicological properties. Less toxic effects are noticed in compounds with higher pola...

Aims The current treatment of Alzheimer's disease is purely symptomatic. Scientists are looking for new treatment options which could alter the course of the disease and improve the quality of life in patients with Alzheimer's disease. In this paper 14 novel s-triazine molecules have been evaluated for their lipophilicity. In addition docking study was carried out to evaluate acetylcholinesterase activity of these compounds. Main methods Lipophilicity was evaluated by RP HPTLC using 5 different mobile phases and obtained results were used in calculations of pharmacokinetic parameters - logBB, Ka and Pej. Multiple linear regression analysis was refined, taking account of molecular polarity (total polar surface area, TPSA) and molecular weight (Mw) descriptors. Appropriate QSAR models were developed. Docking studies were carried out using the Vina docking. Key findings Five out of fourteen compounds evaluated [5-10] are selected as the most promising compounds with satisfactory pharmacokinetic properties and good docking scores. Significance Compound 10 possesses the best combination of favourable pharmacokinetic characteristics (brain penetration, intestinal absorption) and capacity for acetylcholinesterase inhibition. Consequently this molecule should be further evaluated for potential therapeutic use in Alzheimer's disease.

Silymarin is a complex of five major compounds, and silibinin is the most biologically active component of the complex. The aim of this study was to investigate, evaluate and confirm the potential cardioprotective and hepatoprotective effects of administration of silymarin, rich in silibinin, at a dose of 60 mg/kg orally for a time-span of 12 days on doxorubicin induced toxicity in male Wistar rats. The in vivo model was used to explore whether silymarin could prevent damage of liver and heart tissue induced by doxorubicin administered every other day at dose of 1.66 mg/kg intraperitoneally for twelve days. In the study the change of body weight, ECG changes, biochemical parameters of oxidative stress, serum activity of alanine and aspartate transaminase, lactate dehydrogenase, creatine kinase and histological preparations of heart and liver samples of treated animals were examined. According to physiological, pharmacological, microscopic and biochemical results, we confirmed that at the examined dose, silymarin exhibits a protective influence on the heart and liver tissue against toxicity induced by doxorubicin.

The pharmacodynamic effect of a 7-day oral treatment with a suspension of Coprinus comatus at doses of 0.835 and 1.670 g/kg in rats was studied. Changes in body weight, bile secretion and hypoglycaemic action were examined together with antipyretic activity and paw oedema tests. Such treatments resulted in a significantly lower increase in the body weight of tested animals (15.73 ± 8.36 g/rat in the untreated group, 8.44 ± 8.23 g/rat (p < 0.05) and 3.18 ± 7.93 g/rat (p < 0.05), for C. comatus 0.835 and 1.67 g/kg, respectively). Hypoglycaemic action was evident only in the glucose load test (6.79 ± 0.61 to 9.70 ± 1.16 (p < 0.05) in the untreated group and 6.47 ± 0.35 to 7.27 ± 0.76 for C. comatus 1.67 g/kg). Histological examination of pancreas cross-sections suggested certain protective functions of the mushroom suspension in alloxan poisoning. In the antipyretic test, a significantly lower increase in body temperature was observed in the mushroom-pretreated rats. In the paw oedema test, no decrease in oedema induced by formalin injection was observed following treatment with C. comatus.

Introduction: Distribution coefficient (D) is useful parameter for evaluating drugs permeability properties across biological membranes, which are of importance for drugs bioavailability. Given that bile acids are intensively studied as drug permeation-modifying and -solubilizing agents, the aim of this study was to estimate the influence of sodium salts of cholic (CA), deoxycholic (DCA) and 12-monoketocholic acids (MKC) on distribution coefficient of simvastatin (SV) (lactone [SVL] and acid form [SVA]) which is a highly lipophilic compound with extremely low water solubility and bioavailability.Methods: LogD values of SVA and SVL with or without bile salts were measured by liquid-liquid extraction in n-octanol/buffer systems at pH 5 and 7.4. SV concentrations in aqueous phase were determined by HPLC-DAD. Chem3D Ultra program was applied for computation of physico-chemical properties of analyzed compounds and their complexes.Results: Statistically significant decrease in both SVA and SVL logD was observed for all three studied bile salts at both selected pH. MKC exerted the most pronounced effect in the case of SVA while there were no statistically significant differences between observed bile salts for SVL. The calculated physico-chemical properties of analyzed compounds and their complexes supported experimental results.Conclusions: Our data indicate that the addition of bile salts into the n-octanol/buffer system decreases the values of SV distribution coefficient at both studied pH values. This may be the result of the formation of hydrophilic complexes increasing the solubility of SV that could consequently impact the pharmacokinetic parameters of SV and the final drug response in patients.

The interaction of aqueous solutions of stevioside and bile acids with cardioactive drugs was studied in rats by registering changes in their electrocardiograms (ECG). Wistar rats of both sexes received daily doses of 20 mg/kg (i.p.) of an aqueous solution of stevioside or physiological solution (controls), then were narcotized with urethane and connected to the ECG apparatus for the first recording. The jugular vein was prepared and connected to an infusion pump to administer one of the drugs: adrenaline (0.1 mg/ml), verapamil (2.5 mg/ml) or metoprolol (1 mg/ml) to rats in both groups, while recording their ECGs. In the second part of the study, the animals were treated in the same way but instead of the stevioside solution received a single dose of 4 mg/kg of monoketocholic acid methyl ester (ME) or sodium salt of the same bile acid (MKHNa), 30 minutes before cardioactive drug infusion. The infusion rate of cardioactive drugs was 0.2 ml/min, except for verapamil (0.1 ml/min). The events observed on ECG recordings were the first myocardial reaction to drug infusion, the second longer-lasting reaction (observed as more extended extrasystoles, decrease in intensity of the QRS complex, or changes in heart rate frequency), and toxicity effect. In the control animals, adrenaline induced a decrease in heart rate frequency at a dose of 0.094 mg/kg, while with stevioside-pretreated rats this effect appeared significantly earlier (at a dose of 0.018 mg/kg). No toxic effect of adrenaline was observed, either in control or stevioside-pretreated group. Bile acids caused no changes in myocardial reaction to adrenaline. Only in the group of animals that received MKHNa, a significant decrease in the QRS complex was observed. Finally, the infusion of stevioside to intact animals at doses of 45 and 55 mg/kg caused no significant changes in the ECG patterns. The myocardial reaction to metoprolol remained unchanged in rats of all groups when compared with controls except for a mild decrease in heart rate frequency. Stevioside induced/produced a significant increase in myocardial sensitivity to verapamil, but no toxic effect was observed in any of the cases. A similar conclusion also holds for the interaction with MKHNa, whereas ME caused an increase in the toxicity of verapamil.

Influence of two newly synthesized bile acids derivates, namely sodium salt of monoketocholic acid MKH-Na and methyl ester of monoketocholic acid MKH-Me on tramadol (12.5 mg/kg oral and intramuscular) analgesic effect was examined in this research. Analgesic effect was measured by antinociceptive hot plate method. Interaction was estimated by detection of changes in analgesic effect of tramadol combined with bile acids (subcutaneous administration of 4 mg/kg 20 min before tramadol) compared to analgesic effect of the same dose of tramadol given alone. Hydrosoluble sodium salt of monoketocholic acid did not show interaction with tramadol, regardless of the route of administration of tramadol. However, methyl ester of monoketocholic acid increased the analgesic effect of tramadol when it was given intramuscularly. After oral administration of tramadol, methyl ester of monoketocholic acid decreased the analgesic effect of tramadol. According to the time point when interaction reached statistically significant difference, it can be presumed that after intramuscular administration of tramadol, methyl ester of monoketocholic acid increases tramadol absorption and transport to brain and in that way increases its analgesic effect. The analgesic effect of tramadol after oral administration was decreased, which could be explained by the induction of tramadol metabolism in the liver, but should be examined in more details.

Purpose The aim of this study was to measure the consumption of serum lipid reducing drugs in Serbia from 2004 to 2008, to compare this data with that from Scandinavian countries, and to compare the consumption of lipid lowering drugs and the rate of mortality from cardiovascular diseases in these countries. Methods A population-based study was undertaken to analyse lipid lowering drug consumption using the Anatomical Therapeutic Chemical/Defined Daily Dose methodology. Cause-specific mortality rates were obtained from the WHOSIS annual report for the year 2009. Results In 2008, a total of 1207.44 DDD/1000 inh/day of all drugs, was used in Serbia, of which 38.89% belonged to drugs for cardiovascular diseases. While in Scandinavian countries 17.03–24.80% of drugs for cardiovascular diseases belonged to lipid-lowering drugs, in Serbia it was substantially lower (3%). In 2004 in Serbia, 1.50 DDD/1000 inh/day of statins were used. In 2008, this value was 14.24 DDD/1000 inh/day. In every investigated country, simvastatin made up more than 50% of the consumption of statins. After simvastatin, the next most frequently used statin was atorvastatin, with 5.52, 11.00, 11.17 and 24.82 DDD/1000 inh/day, in Serbia, Denmark, Finland and Norway, respectively. In 2004 Serbia has the highest mortality rate for cardiovascular diseases among investigated countries with 762/100.000 inhabitants and Norway has the lowest rate with 158/100.000 inhabitants. Conclusion The use of lipid lowering drugs is 6–8 times lower in Serbia than in Scandinavian countries but there is an evident rise in lipid lowering drugs consumption in Serbia during years. Copyright © 2010 John Wiley & Sons, Ltd.

Role of BeNzodiazepiNeS iN CaRdiaC SafeTy of low MeThadoNe doSeS iN paTieNTS duRiNg MeThadoNe MaiNTeNaNCe TReaTMeNT S. Petkovic ; V. Mijatovic ; I. Samojlik; S. Vukmirovic ; A. Dickov; and T. Popov Faculty of Medicine, University of Novi Sad, Vojvodina, Serbia; and Institute of Cardiovascular Diseases Vojvodina, Sremska Kamenica, Serbia Introduction: Despite the fact that most of health care professionals are aware of possible respiratory depressant effect of methadone and benzodiazepines coadministration, recently published data reveal that ventricular arrhythmia and cardiac arrest are currently the most frequent adverse event attributed to methadone and benzodiazepine comedication. The aim of this study is to assess cardiac safety of low methadone doses used concomitantely with benzodiazepines in opiate addicts in methadone maintenance treatment (MMT). Material and Methods: A clinical trial in which participated 30 opiate addicts at the start of MMT was performed. ECG (to calculate corrected QT (QTc) interval) and blood sampling (to determine methadone and diazepam concentrations ) were performed in all study participants at 3 time points (before the introduction of MMT, after 1 and 6 mo of MMT). Methadone and diazepam concentrations in serum were determined by using liquid chromatography-mass spectrometry (LC-MS). Results: The length of QTc interval before the introduction of MMT was 411.87 ± 27.22 ms, after 1 month of MMT 425.20 ± 17.71 ms and after 6 months of MMT 423.50 ± 14.72 ms. The mean methadone concentration at observed time points was 176.77 ± 118.56 ng/ mL and 342.86 ± 181.54 ng/mL, respectively, while the mean diazepam concentration was 560.74 ± 436.72 ng/mL and 1045.32 ± 932.72 ng/mL, respectively. There was a statistically significant increase in the length of QTc interval after 1 and 6 months of MMT in comparison to the value before the application of MMT. A statistically significant correlation between the concentration of methadone and QTc interval length after 1 and 6 months of MMT was observed and it remained statistically significant if concentration of diazepam was included. Conclusions: Further studies could clarify the possible role of benzodiazepines in the increasing cardiotoxicity of methadone in opiate addicts in MMT. Acknowledgement: The Ministry of Education and Science of the Republic of Serbia (grant numbered 41012) supported this research work.

e30 Volume 35 Number 8S Conclusion: LHA tends to accept EU requirements as much as it could match local regulation, but local regulation differs significantly from EU. As a consequence, LSU makes additional efforts and communications with LHA and Company, to fulfill each requirement in its own way. The differences could be overcome with harmonization of local regulation with EU and if LHA receive access to EudraVigilance database. Disclosure of Interest: None declared.

Background Serbia is one of the leading countries in the world with respect to mortality from cardiovascular diseases. Drugs that reduce serum lipids belong to the group of drugs that can significantly lower complications of cardiovascular diseases and their utilization in Serbia deserves special attention. The aim of this study was to measure the consumption of serum lipid reducing drugs in Serbia from 2004 to 2010, to compare these data with those from Scandinavian countries, and to compare the consumption of lipid-lowering drugs and the rate of mortality from cardiovascular diseases in these countries.

Background Silymarin, an extract of Silybum marianum seeds, possesses a broad spectrum of action: antifibrotic, antiinflammatory, lipid peroxidation-inhibiting and free radical-scavenging effects. It is a complex of five major compounds, and silibinin is the most biologically active component of the complex. The aim of this study was to investigate, evaluate and confirm the potential antioxidative effects of silymarin rich in silibinin.