Search

Recent findings regarding the physiological transport mechanisms and metabolism of bile acids have led to an increased interest in their synthetic derivatives, especially as transmucous transporters. The aim of this study was to examine the influence of the synthetic sodium salt of monoketocholic acid (Na-MKHA) on the hypolipidemic activity of lovastatin. The effects of a 7 days administration of lovastatin (20 mg/kg b.w.) (experimental group 1,n=5) and a combination of lovastatin (20 mg/kg b.w.) and Na-MKHA (2 mg/kg b.w.) (experimental group 2,n=5) in group of healthy and diabetic male Wistar rats were investigated. The animals in the control group of healthy (n=5) and diabetic (n=5) rats were treated with physiological saline (10 ml/kg b.w.) per os twice a day. In the healthy rats, lovastatin increased the low density lipoprotein (LDL) (32.14%) and non-high density lipoprotein (HDL) (15.38%) cholesterol and decreased HDL cholesterol levels (9.89%), and also increased the investigated atherogenic ratios. Na-MKHA significantly potentiated lovastatin activity, and its effects on the LDL (p

The aim of this study is to investigate how the semisynthetic bile acid; 3alpha,7alpha-dihydroxy-12-keto-5beta-cholanate, also known as 12-monoketocholic acid (MKC) influences the ileal permeation of the antidiabetic drug gliclazide in healthy and diabetic rats. Male Wistar rats were divided into 10 groups (n = 32), of which 5 comprised healthy rats (1 to 5) and 5 diabetic rats (6 to 10). Group 1 was used to measure the permeation of gliclazide (200 microg/ml) alone (control) while in groups 2 to 5 gliclazide permeation was measured in the presence of MKC (50 microg/ml), glibenclamide (100 mug/ml), rifampicin (100 mug/ml) and verapamil (30 microg/ml), respectively, using Ussing chambers. Groups 6 to 10 were treated in the same way, after the induction of type 1 diabetes with alloxan (iv 30 mg/kg). In tissues from healthy rats, there was a 9-fold reduction in the mucosal to serosal permeation of gliclazide in the presence of MKC (p0.001) while glibenclamide and rifampicin reduced the permeation of gliclazide in both directions; mucosal to serosal and serosal to mucosal and verapamil had no effect. In contrast, in diabetic rats, there was no net transport of gliclazide alone or after the addition of MKC, glibenclamide, rifampicin or verapamil. The lack of any net flux of gliclazide in diabetic rats suggests the lack of action of drug transporters involved or the suppression of their expression. Furthermore, MKC-induced inhibition of mucosal to serosal unidirectional flux of gliclazide, in healthy rats, can be the result of the selective inhibition of Mrp3.

The critical micellar concentration (CMC) values of keto derivatives of cholic acid (3alpha,12alpha-dihydroxy-7-oxo-5beta-cholanoic acid, 3alpha,7alpha-dihydroxy-12-oxo-5beta-cholanoic acid, 12alpha-hydroxy-3,7-dioxo-5beta-cholanoic acid, 3alpha-hydroxy-7,12-dioxo-5beta-cholanoic acid, 3,7,12-triketo-5beta-cholanoic acid) and cholic acid itself, were determined. Replacement of hydroxyl groups in cholic acid molecule with keto groups yields the derivatives whose CMC values increase with increase in the number of keto groups introduced. The CMCs of derivatives with the same number of keto groups but at different positions do not differ significantly. The relationship between the number of keto groups in the molecule of cholic acid keto derivatives and CMC value can be described by the following equation: CMC=43 number of keto groups+14.667. The effect of NaCl concentration on CMC increases with increase in the number of keto groups.

e142 Volume 37 Number 8S aspects of development of topical treatments for AD were not specifically addressed. Conclusions: There is little information available to guide the development of topical dermatological products for the treatment of AD and psoriasis. Because recommendations are disperse, and lacking for some development aspects, a systematic approach to create specific guidance to development in AD and P may be useful.

An overview of the structure and the origin of naturally occurring bile acids is given. Most naturally occurring bile acids belong to the 5beta-series, with hydroxyl groups in the A, B, and C ring of the steroid system. Hydroxyl groups are mostly found at the C3, C6, C7, C12 and C23 positions and are a- rather than beta-oriented. In most bile acids, the A/B ring junction is cis (5beta-series). However, the A ring can be usually present in the more stable (chair) or less stable (boat) conformation. Both B/C and C/D ring junction are trans. With respect to the angular C19-methyl group, the hydrogen atoms at C5 and C8 are cis-oriented whereas those at C9 and C14 are trans-oriented. The archetypal bile acid is 5beta-cholanic acid (3) from which all other C24 bile acids can be derived. In addition to the bile acids with 24 carbons, some naturally occurring C27 bile acids have been identified including di-, tri- and tetra-hydroxy derivatives of coprostanic acid isolated from bile of several reptile species. The most dominant bile acids and their natural sources are given and a selection of naturally occurring bile acids with unusual structures which have been mostly isolated from the bile of reptiles and amphibians is described.

The role of bile acids in pharmacotherapy is reviewed in this article. The therapeutic use of bile has been recognized since ancient times. Previously bile acids were the standard treatment for gallstones where chenodeoxycholic acid and ursodeoxycholic acid were effective in promoting the dissolution of cholesterol gallstones. Today their therapeutic role looks set to expand enormously. Bile acids as absorption promoters have the potential to aid intestinal, buccal, transdermal, ocular, nasal, rectal and pulmonary absorption of various drugs at concentrations that are non-toxic. Keto derivatives of cholic acid, such as 3a,7a,dihydroxy-12-keto-5alpha-cholic acid (sodium salt and methyl ester) are potential modifiers of blood-brain barrier transport and have been shown to promote quinine uptake, enhance the analgesic effect of morphine and prolong the sleeping time induced by pentobarbital. They have also been shown to be hypoglycaemic. Bile acids as therapeutic agents have the potential to produce beneficial effects in sexually transmitted diseases, primary biliary cirrhosis, primary sclerosing cholangitis, gallstones, digestive tract diseases, cystic fibrosis, cancer and diabetes.

The pharmacokinetics of a new verapamil retard tablet formulation have been investigated in a randomized cross-over bioequivalence study on 12 healthy subjects. The drug was given orally at a single new or standard retard tablet dose of 240mg and at a single intravenous dose of 5mg. Plasma verapamil concentrations were determined by HPLC. New retard tablets produced peak plasma verapamil concentrations of 81.34+/-5.69microg/l, time to peak plasma concentrations of 4.91+/-0.89h and an AUC (0-24h) of 1291+/-103.4h x microg/l, with a terminal phase half-life of 55.1+/-14.9h. After intravenous administration verapamil exhibited biphasic elimination kinetics with a terminal plasma half-life of 2.36+/-0.42h and systemic clearance of 34.32+/-5.81 l/h. Bioavailability of the new peroral retard formulation ranged from 19.49+/-4.41% to 67.69+/-11.70%. Absorption rates and amounts were evaluated by means of the spline-convolutional method. Input rates for the new verapamil retard formulation ranged from 0.77+/-0.20mg/h to 5.57+/-1.58mg/h. The cumulative amount of verapamil input was 39.17+/-9.71% for the new retard tablets. All pharmacokinetic parameters for the new verapamil retard tablet formulation, were in reasonable agreement with the data obtained on already registered verapamil retard formulations, indicating their bioequivalence.

A study was made of the combined effect of two commercial products of Stevia rebaudiana Bertoni and sodium monoketocholate (mkc) on blood glucose concentration in mice. One group of animals was treated four days with mkc, 4 mg/kg, s. c, second with 200 mg/kg, i. p. , of Stevita (Stevita Co, INC, Arlington, Texas) (stevia), third with 20 mg/kg, i. p. , of Clear Steviosides Liquid (Stevita Co, INC, Herbal supplement, Brazil) (stevioside), fourth with the combination of stevia and mkc, and the fifth with stevisode and mkc. Blood glucose concentration was measured before treatment, after the first and fourth dose, as well as after subjecting animals to glucose-tolerance test (500 mg/kg, p. o. ) or provoking glycemia by injecting adrenaline (0. 2 mg/kg, s. c). It was found that one dose of stevioside combined with mkc caused a significant increase of glycemia with respect of mkc alone and control (10. 80:7. 90:8. 01). However, when repeated four days, the same pretreatment resulted in a significant decrease of glycemia compared with single-dose pretreatment (10. 80:7. 20). The increase in glycemia with the mice that received four doses of stevioside and mkc and then were subjected to glucose-tolerance test was significantly lower compared to that in mice that were pretreated four days only with mkc before receiving glucose (6. 33:7. 80). Analogous difference was observed between the animals given mkc alone and mkc plus stevioside after injecting adrenaline ( 13. 33:10. 54). As for the interaction of mkc and stevia it was found that the combined pretreatment yielded lower values of glycemia compared with that measured after treatment with stevia alone (6. 40:7. 82).

The aim of the study was to test the efficacy of 3alpha,7alpha-dihydroxy-12-oxo-5beta-cholanate as a blood-brain barrier (BBB) permeator by examining its effect on quinine uptake into the central nervous system in rats, analgesic action of morphine, and on the sleeping time induced by pentobarbital. The obtained results indicate that sodium 3alpha,7alpha-dihydroxy-12-oxo-5beta-cholanate can be considered as modifier of BBB permeability, as it exhibited a promoting effect in all three tests. In the test of quinine uptake, methyl ester of 3alpha,7alpha-dihydroxy-12-oxo-5beta-cholanoic acid (included in the study for comparison) did not show a promoting effect, which can suggest its specific action.

EFFECTS OF BILE ACIDS AND THEIR SALTS ON ABSORPTION OF OTHER SUBSTANCES: Bile acids and their salts increase intestinal absorption of lipids and transmembrane and paracellular transfer of small and endogenous and exogenous polar molecules. It has been established that they are good promotors of insulin absorption through skin and nasal mucose, and of blood-brain barrier transfer of salycilates and quinine.It has been established that combination of bile acids with amphotericin B has potential Leishmanicideal effect and combination with ciprofloxacine has improved its antibacterial activity against Pseudomonas aeruginosa in vitro.PHARMACADYNAMIC EFFECTS: Bile acids have analgesic and hypoglycemic effect. They also have anti-HIV effect probably suppressing virus transmission from cell to cell.New studies of natural bile acids and new synthetic bile acids have revealed that they are not only adjuvants to existing active principles in pharmaceutical forms, but they can act as new therapeutic agents. However, it is necessary to study their possible mechanisms, but they are not crucial for their therapeutic application. Toxicological and pharmacological studies will determine the role of newly synthesized bile acids and their salts in current therapy.

Armin Mooranian,1 Rebecca Negrulj,1 Nigel Chen-Tan,2 Hesham S Al-Sallami,3 Zhongxiang Fang,4 TK Mukkur,5 Momir Mikov,6,7 Svetlana Golocorbin-Kon,6,7 Marc Fakhoury,8 Gerald F Watts,9 Vance Matthews,10 Frank Arfuso,5 Hani Al-Salami1 1Biotechnology and Drug Development Research Laboratory School of Pharmacy, Curtin Health Innovation Research Institute, Biosciences Research Precinct, Curtin University, Perth, Western Australia, Australia; 2Faculty of Science and Engineering, Curtin University, Perth, Western Australia, Australia; 3School of Pharmacy, University of Otago, Dunedin, New Zealand; 4School of Public Health, Curtin University, Perth, Western Australia, Australia; 5Curtin Health Innovation Research Institute, Biosciences Research Precinct, School of Biomedical Science, Curtin University, Perth, Western Australia, Australia; 6Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Serbia; 7Department of Pharmacy, Faculty of Medicine, University of Novi Sad, Serbia; 8Faculty of Medicine, University of Montreal, Montreal, Quebec, Canada; 9School of Medicine and Pharmacology, Royal Perth Hospital, University of Western Australia; 10Laboratory for Metabolic Dysfunction, UWA Centre for Medical Research, Harry Perkins Institute of Medical Research, Perth, Western Australia, Australia Introduction: In previous studies, we successfully designed complex multicompartmental microcapsules as a platform for the oral targeted delivery of lipophilic drugs in type 2 diabetes (T2D). Probucol (PB) is an antihyperlipidemic and antioxidant drug with the potential to show benefits in T2D. We aimed to create a novel microencapsulated formulation of PB and to examine the shape, size, and chemical, thermal, and rheological properties of these microcapsules in vitro. Method: Microencapsulation was carried out using the Büchi-based microencapsulating system developed in our laboratory. Using the polymer, sodium alginate (SA), empty (control, SA) and loaded (test, PB-SA) microcapsules were prepared at a constant ratio (1:30). Complete characterizations of microcapsules, in terms of morphology, thermal profiles, dispersity, and spectral studies, were carried out in triplicate. Results: PB-SA microcapsules displayed uniform and homogeneous characteristics with an average diameter of 1 mm. The microcapsules exhibited pseudoplastic-thixotropic characteristics and showed no chemical interactions between the ingredients. These data were further supported by differential scanning calorimetric analysis and Fourier transform infrared spectral studies, suggesting microcapsule stability. Conclusion: The new PB-SA microcapsules have good structural properties and may be suitable for the oral delivery of PB in T2D. Further studies are required to examine the clinical efficacy and safety of PB in T2D. Keywords: artificial cell microencapsulation, diabetes, antioxidant, anti-inflammatory, Probucol

Summary Enflurane is a fluorinated volatile anesthetic, mostly eliminated unchanged in exhaled air. About 10 % of inhaled enflurane undergoes oxidative metabolism in liver via mixed function oxidase. We examined the influence of ethanol and subchronical exposition (6 hours a day, during five consecutive days) to subanesthetic and anesthetic concentrations of enflurane on liver function in BALB/c mice. Specially designed chamber for inhalatory application of anesthetics was constructed for this study. Animals were divided in six groups of twenty. The ethanol treated group was injected with ethanol intraperitoneally (1 g/kg). Two enflurane treated groups were intraperitoneally injected with 0.9 % solution of sodium chloride (10 ml/kg) and one of them exposed to subanesthetic (0.5 Vol%) and the other one to anesthetic (2.75 Vol%) concentrations of enflurane. Following two groups received ethanol (1 g/kg) and each of them inhaled enflurane at previously mentioned doses. The control group was intraperitoneally injected with 0.9 % solution of sodium chloride (10 ml/kg) and did not receive any anesthetic. On the day following the last day of exposure half of the animals from each group were sacrificed for determination of glucose levels, erythrocyte glutathion levels, haematocrit, alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), liver protein and glutathion levels, and total cytochrome P-450 (CYP P-450). The other half of animals from each group were injected intraperitoneally with caffeine (20 mg/kg). Caffeine and its metabolites in 8 hour urine were analyzed by high performance liquid chromatography (HPLC) method. Excretion of caffeine and its metabolites was different among the groups. We followed two caffeine metabolic ratios — 1,3-dimethyl uric acid and 3,7-xanthine (1,3-U/3,7-X) and 3,7-dimethyl xanthine + 7-xanthine and 1-xanthine + 1,7-dimethyl uric acid (3,7-X + 7-X/1-X + 1,7-U). The difference in caffeine metabolites ratios suggests that enflurane changes oxidative metabolism in liver via certain subtypes of mixed function oxidase, probably via CYP-4502E1. This effect is more expressed when ethanol and enflurane are applied together. Ethanol is well known inductor of CYP-4502E1 and the registrated enzyme induction could be explained by both influences — of ethanol and enflurane.

2013 e83 PP208—Deoxycholic AciD As A MoDifier of the BlooD BrAin BArrier PerMeAtion in rAt M. Lalic-Popovic; S. Golocorbin-Kon; V. Vasovic; B. Milijasevic; and M. Mikov Department of Pharmacy, Faculty of Medicine, Novi Sad, Serbia; Faculty of Pharmacy, University of Montenegro, Podgorica, Montenegro; and Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, Novi Sad, Serbia Introduction: Major problem for diabetic patients represents damage of blood vessels and the oxidative stress of the brain cells due to increased concentration of free radicals and poor nutrition of brain cells. Gliclazide has antioxidative properties and poor blood brain barrier (BBB) penetration. Bile acids are known for their hypoglycemic effect and as prooters of drug penetration across biological membranes. Aim: The aim of this study is to investigate whether the bile acid (deoxycholic acid) can change the permeation of gliclazide, through the blood brain barrier of a rat model type-1 diabetes. Patients (or Materials) and Methods: Twenty-four male Wistar rats were randomly allocated to 4 groups, of which 2 were given alloxan intraperitoneally (100 mg/kg) to induce diabetes. One diabetic group and 1 healthy group were given a bolus gliclazide intra-arterially (20 mg/kg), while the other 2 groups apart from gliclazide got deoxycholic acid (4 mg/kg) subcutaneously. Blood samples were collected 30, 60, 150, and 240 seconds after dose, brain tissues were immediately excised, and blood glucose and gliclazide concentrations were measured. Results: Penetration of gliclazide in groups without deoxycholic acid pretreatment was increased in diabetic animals compared with healthy animals. Also in both, healthy and diabetic animals, deoxycholic acid increased the permeation of gliclazide through that in BBB. Deoxycholic acid pretreatment also changed the pattern of blood glucose level increase after gliclazide application in diabetic as well as in healthy animals. Conclusion: Deoxycholic acid promotes gliclazide penetration across BBB in diabetic and in healthy animals. In addition, deoxycholic acid alters some pharmacokinetic properties of gliclazide in both healthy and diabetic rats. Thus, deoxycholic acid should be more investigated in the treatment of diabetes mellitus and as permeation promoter of lipophilic molecules through BBB as well as other biological membranes. Financial Source: This work has been supported by Ministry of Science and Technology development of Serbia N041012.

Background Cardiovascular diseases are the most frequent cause of morbidity and mortality in many countries. That explains why medications for the treatment of cardiovascular diseases are the group of drugs with the largest consumption, and ACE inhibitors take a large part in this consumption. The aim of this study was to analyze the consumption of ACE inhibitors in Serbia in 2010 compared with Norway, a country with a developed pharmacotherapeutic practice.

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.

Methods The essential oil (EO) of caraway, prepared as emulsion for peroral use, was applied to male mice during 5 consecutive days. Paracetamol, in the dose of 200 mg/kg, was applied p.o. or i.p. 2 hours after the last EO dose. Blood samples for pharmacokinetic assay were collected from the tail vein before paracetamol intake and 10, 30, 60, 90 and 120 min thereafter. Blood concentrations of paracetamol were determined by HPLC and the pharmacokinetic parameters were calculated using the WinNonlin software.

Results The overall consumption of medicines from A02B subgroup in 2010 in Serbia was 22.9 DID, whereas in Croatia and Sweden was 32.8 DID and 48.6 DID, respectively. In Serbia, H2RAs accounted for 71.8% (16.5 DID) of medicines used within A02B subgroup, while in Croatia H2RAs accounted for 37.3% (12.2 DID) and in Sweden 2.2% (1.1 DID). In the same year, the utilization of PPIs in Serbia (6.5 DID) was more than three times lower than in Croatia (20.6 DID) and more than seven times lower than in Sweden (47.3 DID). The bulk of prescription (DU90%) was made up of 3 (out of 7) medicines in Serbia, 5 (out of 8) medicines in Croatia and 5 (out of 14) medicines in Sweden. The most frequently used medicine from the A02B subgroup in Serbia was ranitidine (56.0%, i.e. 12.8 DID), in Croatia pantoprazole (36.5%, i.e.12.0 DID) and in Sweden omeprazole (81.3%, i.e. 39.0 DID).

Background Potentially inappropriate medications (PIMs) continue to be prescribed and used as first-line treatment for the most vulnerable of older adults, despite evidence of poor outcomes from the use of PIMs in older adults. PIM use is an important and preventable safety concern in the care of elderly patients and has been associated with adverse drug reactions, hospitalization and mortality. The aim of this study was to estimate the prevalence of PIM use among the elderly in Montenegro in 2012.

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.

Gut flora and gut contents can be considered as a system with huge metabolic capacity, qualitatively and quantitatively different from the body cells and organs. That system changes along with life and nutrition, but despite broad investigation has not yet been defined satisfactorily. In many cases inter individual and intra individual differences in drug metabolism could be linked to variations in the gut flora metabolism. Gut flora metabolism of drugs and other xenobiotic metabolites excreted in bile is the key phase responsible for enterohepatic circulation. In the last decade there has been more and more evidence for the crucial role of the gut flora cysteine conjugate beta-lyase in the metabolism of cysteine conjugates. A new pathway for paracetamol cysteine conjugate metabolism has been directly linked with gut flora activity, as demonstrated in our studies. Nowadays, it is quite clear that gut flora metabolism must be considered an integral part of drug metabolism and toxicity studies.

Although it is now generally regarded that the origin of urinary trimethylamine (TMA) is via the action of intestinal microflora on precursors such as choline, little direct evidence exists. The normal production of urinary TMA was shown to be absent in germ-free mice and greatly reduced in antibiotic-pretreated animals. Cohabitation of germ-free mice with conventional animals restored their ability to excrete TMA. This study invokes a fundamental role for the intestinal microflora in the provision of TMA from precursors within the food.

Benzene has been widely used as a solvent, but its use is declining in most developed countries because it is a well established human carcinogen. An association between occupational exposure to benzene and health effects such as aplastic anaemia and leukaemia has been reported in studies of workers in various industries. For many solvent uses benzene has been replaced by other less toxic organic solvents and is considered a toxic impurity in other industrial solvents, but it is still used as a starting material in numerous chemical syntheses. In addition to industrial sources, benzene is present in the environment as a component of cigarette smoke and automobile emissions. Benzene induces hematotoxicity as a result of chronic exposure. Acute exposure to benzene causes neurotoxic and hepatotoxic effects. Toxic effects of benzene, chronic as well as acute, are the consequence of the unknown reactive metabolite produced by cytochrome P-450. Benzene is metabolized mainly by ethanol inducible cytochrome P-4502E1 (CYP2E1) in animal and human liver microsomes. Ethanol is consumed worldwide in tremendous amounts and is an effective inducer of hepatic xenobiotic metabolism, especially involving pathways accomplished by the isoform CYP2E1 of cytochrome P-450. Therefore, whenever xenobiotics that are substrates of CYP2E1, such as many organic solvents, are taken in by an individual who is also chronically consuming ethanol, the accelerated metabolism of these agents has to be considered. In contrast to the long-term consumption of ethanol, which induces the hepatic metabolism of xenobiotics, short-term consumption inhibits their metabolism because of direct competition for CYP2E1. Ethanol, when given to a living body, exerts dual effects on the xenobiotic metabolizing enzymes, i.e., inhibition and stimulation. Which one is more predominant over the other depends on the time that has elapsed after ethanol ingestion. In an early period when ethanol exists in the body in high concentrations, it may preferentially act as an inhibitor . In this study, effect of simultaneous exposure to benzene and ethanol on benzene metabolism in mice were investigated by measuring the concentration of phenol, the main metabolite of benzene.

The aim of this study was to investigate the influence of sodium 3alpha,7alpha-dihydroxy-12-keto-5beta-cholanate (MKC) on the ileal permeation of gliclazide in healthy and diabetic rats treated with probiotics. Male Wistar rats (2-3 months, 350 +/- 50 g) were randomly allocated into four groups (n = 32); Groups 1 and 2 were healthy controls and Groups 3 and 4 were diabetic rats (alloxan 30 mg/kg was administered i.v.), which were administered probiotics for three days after the rats became diabetics. The rats were sacrificed and tissues were mounted on Ussing chambers. Then, gliclazide (200 microg/ml) was added to all the groups, while MKC (50 microg/ml) was given to Groups 2 and 4, for the measurement of the mucosal to serosal absorption Jss(MtoS) and serosal to mucosal secretion Jss(StoM) of gliclazide. In the tissues of healthy rats treated with probiotics, MKC stimulated the net absorption of gliclazide by stimulating the absorptive and reducing the secretory unidirectional fluxes, while in tissues from diabetic rats treated with probiotics, MKC had no effect. In healthy rats treated with probiotics, the degradation of MKC by bacterial polypeptides produced divalent bile salts that inhibited Mrp2, which resulted in reducing secretion and stimulating the absorption of gliclazide. In contrast, in diabetic rats treated with probiotics, MKC had no effect possibly due to a difference in the metabolic profile and resulting in no net flux.

The contribution of the gastrointestinal microflora to the formation of methylthio adducts from paracetamol has been studied by comparing the fate of this drug in conventional mice with that in germ-free and neomycin-treated animals. In both germ-free and neomycin-treated mice there was a highly significant reduction in the urinary excretion of 3-methylthioparacetamol, its glucuronic acid and sulfate conjugates and its sulfoxide, with no other systemic alteration to the overall fate of the drug. These data are consistent with the gut flora playing a major role in the C-S cleavage of paracetamol-3-cysteine, thereby reducing the excretion of the array of methylthio adducts subsequently formed by tissue enzymes from 3-thioparacetamol, the putative product of the C-S cleavage.

Smart polymers such as Eudragit (ED) have shown potential applications in oral drug delivery and targeted release. Probucol (PB) is a lipophilic drug used for hypercholesterolemia and possesses desirable antidiabetic effects such as antioxidant and cell protective effects. PB is highly hydrophobic and has poor bioavailability with significant inter- and intra-patient absorption, limiting its clinical applications in diabetes. This study aimed to design and analyse new PB-ED formulations with or without the absorption-enhancer chenodeoxycholic acid (CDCA). Sodium alginate-based microcapsules containing three different ED polymers (NM30D, RL30D and RS30D) were investigated with or without CDCA via scanning electron microscopy, energy dispersive X-ray spectroscopy (EDXR), confocal microscopy, osmotic stability, mechanical properties, buoyancy, release profiles (pH: 7.4), thermal stability and antioxidant effects. The effects of microcapsules on pancreatic β-cell survival, function, inflammatory profile and PB cellular uptake were analysed. All microcapsules showed uniform morphology and surface topography with CDCA being distributed evenly throughout the microcapsules. Osmotic stability was significantly improved in PB-NM30D and PB-RL30D microcapsules (p .01 and p .05, respectively), and PB-NM30D microcapsules displayed low buoyancy (p .01). CDCA improved PB-NM30D effects on pancreatic β-cell function and bioenergetics, which suggests potential application of PB-NM30D-CDCA in PB delivery and diabetes treatment.

Introduction Ranitidine is a hydrophilic weak base and an H 2 -receptor antagonist which is commonly used for gastroesophageal reflux, including during pregnancy. It has limited placental permeation and can be used as a pre-anesthetic antacid to prevent aspiration of acidic stomach contents. Recent studies suggest that diabetes and hypertension may influence placental permeation of hydrophilic drugs. Thus, this study aimed to investigate the influence of diabetes and hypertension on ranitidine's placental permeation in pregnant women. Methods Forty one pregnant women all scheduled for elective cesarean section entered the study: healthy control (n = 15), with hypertension (n = 16) and with gestational diabetes (n = 10). All women received 50 mg of ranitidine intravenously. Three samples of maternal plasma (after ranitidine application, at delivery and after delivery), and two umbilical cord samples (arterial and venous blood) were collected and analyzed for ranitidine concentrations. Maternal pharmacokinetic parameter were calculated as well as feto:maternal and umbilical cord arterial to venous concentration ratios. Results Ranitidine maternal and umbilical cord (arterial and venous) concentrations were similar in all three groups and there were no difference between feto:maternal ratios nor volume of distribution, clearance and half life between the groups. Discussion Fetal concentrations are dependent on maternal concentrations in healthy and hypertensive women but not in diabetic women. Hypertension and diabetes did not affect fetal handling of ranitidine. Though hypertension and diabetes did not influence ranitidine placental permeation, it appears they altered time needed to achieve unity between maternal and fetal plasma.

Aim: Deoxycholic acid (DCA) has improved gliclazide oral absorption, while Eudragit® (ED) polymers have improved formulation stability of antidiabetic drugs. The aim of the study is to test if DCA and ED encapsulation will optimize the release and stability of the potential antidiabetic drug probucol (PB). Materials & methods: The PB formulations were prepared using ED polymers and DCA, and formulations were analyzed for their rheological and biological properties. Results: Rheological properties and size distribution were similar among all groups. β-cell survival and biological activities were best with NM30D microcapsules. The inflammatory profile and oxidative stress effects of microcapsules remained similar among all groups. Conclusion: ED NM30D and DCA incorporation can exert positive and stabilizing effects on PB oral microcapsules.

Following the drug administration, patients are exposed not only to the parent drug itself, but also to the metabolites generated by drug-metabolizing enzymes. The role of drug metabolites in cytochrome P450 (CYP) inhibition and subsequent drug-drug interactions (DDIs) have recently become a topic of considerable interest and scientific debate. The list of metabolites that were found to significantly contribute to clinically relevant DDIs is constantly being expanded and reported in the literature. New strategies have been developed for better understanding how different metabolites of a drug candidate contribute to its pharmacokinetic properties and pharmacological as well as its toxicological effects. However, the testing of the role of metabolites in CYP inhibition is still not routinely performed during the process of drug development, although the evaluation of time-dependent CYP inhibition during the clinical candidate selection process may provide information on possible effects of metabolites in CYP inhibition. Due to large number of compounds to be tested in the early stages of drug discovery, the experimental approaches for assessment of CYP-mediated metabolic profiles are particularly resource demanding. Consequently, a large number of in silico or computational tools have been developed as useful complement to experimental approaches. In summary, circulating metabolites may be recognized as significant CYP inhibitors. Current data may suggest the need for an optimized effort to characterize the inhibitory potential of parent drugs metabolites on CYP, as well as the necessity to develop the advanced in vitro models that would allow a better quantitative predictive value of in vivo studies.

nema

There were significantly higher carboxyhaemoglobin blood concentrations in mothers who were smokers than those in mothers who were non-smokers and ex-smokers ( P < 0.001). Carboxyhaemoglobin blood concentrations in newborn infants were nearly one-third higher than those in their mothers. Newborn infants from mothers who smoked had lower birthweights and higher carboxyhaemoglobin blood concentrations than those in newborn infants from mothers who were non-smokers and ex-smokers. Smoking during pregnancy increases the risk for a baby. This finding shows the importance of women giving up smoking during pregnancy.

The aim is to investigate the influence of the antidiabetic drug gliclazide on the ileal permeation of the semisynthetic bile acid, MKC, in tissues from healthy and diabetic rats. Sixteen Wistar rats (350 +/- 50 g) were randomly allocated into four groups (4 rats per group, 8 chambers per rat, i.e., n=32) two of which were made diabetic (given alloxan i.v. 30 mg/kg). Group 1 was used to measure the permeation of MKC (50 microg/ml) alone (control) while group 2 to measure MKC permeation in the presence of gliclazide (200 microg/ml). The diabetic groups 3 (gliclazide) and 4 (MKC+gliclazide) were treated in the same way. Rats were sacrificed and tissues were mounted into the Ussing chamber for the measurement of MKC mucosal to serosal (absorptive) and serosal to mucosal (secretory) fluxes. In healthy tissues, gliclazide reduced MKC absorptive flux (p0.01) and increased its secretory flux (p0.01). In diabetic tissues, gliclazide had no effect on either the absorptive or the secretory fluxes of MKC. The lack of effect of gliclazide on MKC permeation in diabetic tissues suggests the absence or suppressed drug transporters. Furthermore, gliclazide inhibition of MKC absorptive flux and induction of MKC secretory flux in healthy tissues may result from the selective inhibition of an efflux drug transporter.