Ursodeoxycholic and chenodeoxycholic bile acids attenuate systemic and liver inflammation induced by lipopolysaccharide in rats.

Bacterial lipopolysaccharide (LPS) induces general inflammation, by activating pathways involving cytokine production, blood coagulation, complement system activation, and acute phase protein release. The key cellular players are leukocytes and endothelial cells, that lead to tissue injury and organ failure. The aim of this study was to explore the anti-inflammatory, antioxidant, and cytoprotective properties of two bile acids, ursodeoxycholic acid (UDCA) and chenodeoxycholic acid (CDCA) in LPS-induced endotoxemia in rats. The experiment involved six distinct groups of Wistar rats, each subjected to different pretreatment conditions: control and LPS groups were pretreated with propylene glycol, as a bile acid solvent, while the other groups were pretreated with UDCA or CDCA for 10 days followed by an LPS injection on day 10. The results showed that both UDCA and CDCA reduced the production of pro-inflammatory cytokines: TNF-α, GM-CSF, IL-2, IFNγ, IL-6, and IL-1ß and expression of nuclear factor-κB (NF-κB) induced by LPS. In addition, pretreatment with these bile acids showed a positive impact on lipid profiles, a decrease in ICAM levels, an increase in antioxidant activity (SOD, |CAT, GSH), and a decrease in prooxidant markers (H2O2 and O2-). Furthermore, both bile acids alleviated LPS-induced liver injury. While UDCA and CDCA pretreatment attenuated homocysteine levels in LPS-treated rats, only UDCA pretreatment showed reductions in other serum biochemical markers, including creatine kinase, lactate dehydrogenase, and high-sensitivity troponin I. It can be concluded that both, UDCA and CDCA, although exerted slightly different effects, can prevent the inflammatory responses induced by LPS, improve oxidative stress status, and attenuate LPS-induced liver injury.

Antihypertensive drugs in blood donations in Serbia - Observational study.

INTRODUCTION: Most of the blood banks worldwide do not defer donors for their medication, with the exception of the teratogenic and platelet aggregation-inhibiting drugs use. In Serbia, where around 245.000 units of blood are collected each year, it is not common practice to consider the medication of potential blood donors. Therefore, the aim of this study was to quantify the presence of antihypertensive drugs in blood samples collected from blood donors treated for hypertension and to raise the issue of the recipient risks posed by drug residues in blood products. METHODS: Serum samples were obtained from 450 volunteer blood donors collected during the year 2017 who reported the use of antihypertensive drugs. All blood donors were required to interrupt regular antihypertensive therapy for 24 h before blood donation and LCMS determination of antihypertensive drugs was performed. RESULTS: Beta blockers were detected in 81 out of 203 samples which tested positive for the presence of antihypertensive drugs. Concentrations above the limit of quantification were determined in 58% of samples positive on beta blockers, containing metoprolol and bisoprolol in amounts sufficient to produce a therapeutic effect in the recipient. CONCLUSION: Therefore, the obtained results suggested that the safety of blood donation from individuals with treated hypertension should not be neglected. A solution for this problem might be the establishment of a standard LCMS screening procedure as a tool for testing the blood of donors taking drugs.

Impact of winter savory extract (Satureja montana L.) on biochemical parameters in serum and oxidative status of liver with application of the principal component analysis in extraction solvent selection.

OBJECTIVE: Satureja montana L. is traditionally used as spice and for treatment various diseases. Many studies have shown antioxidative effect of Satureja species. Our thorough study in an animal model was performed through measurement of biochemical parameters in the serum, histology analysis and determination of oxidative status of the liver, coupled with investigation of extraction solvent selection using principal component analysis (PCA). MATERIALS AND METHODS: Winter savory dry extract (500 mg/kg) dispersion and saline solution were given to Wistar rats for 7 days after exposure to oxidative stress using toxic doses of paracetamol (600 mg/kg). Rats were sacrificed, after which a complete autopsy was performed, the blood obtained was used to determine biochemical parameters, and the liver was sliced for histological analysis and determination of oxidative stress enzymes. RESULTS: Indicators of hepatic and kidney functions, as well as the concentration of oxidative stress enzymes, were statistically significantly lower in animals treated with Satureja montana L. extract compared to the paracetamol group alone before the toxic dose of paracetamol. Liver enzymes were unaltered by pre-treatment with the extract, but the level of lipid peroxidase was decreased, and the level of catalase, glutathione reductase and superoxide dismutase increased proving in vivo antioxidant effect. In addition, the number of inflammatory cells is decreased coupled with activity of CYP2E1 enzymes proving hepatoprotective effect. CONCLUSIONS: Satureja montana L. extract in our research has shown hepatoprotective, anti-inflammatory and antioxidative effect. PCA analyses indicated that extraction mediums have a great impact on the antioxidative effect.

Molecular mechanism of action and pharmacokinetic properties of methotrexate.

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.

Potentials of human bile acids and their salts in pharmaceutical nano delivery and formulations adjuvants.

In the last decade, the attention of the scientific community has been focused on bile acids and their salts as systems for the transportation of drugs; specifically their role as carriers and integration into nanomedicine. Bile acids can play a critical role as drug carriers in the form of chemical conjugates, complexation, mixed micelles formation as well as stabilized bile acid liposomes (bilosomes). The unique molecular structure and interaction of these amphiphilic-steroidal compounds make them an interesting subject of research. This review is based on literature research in order to emphasize the importance of bile acids and their salts as absorption modulators in order to improve therapeutic potentials of low bioavailability drugs.

Docking-based preliminary study on the interactions of bile acids with drugs at the transporter level in intestinal bacteria.

OBJECTIVE: The aim of this study was to estimate the binding-affinities of different bile acids towards drug transporters in Lactobacillus acidophilus and Bifidobacterium longum in order to predict the influence of bile acids and probiotics interactions on drug pharmacokinetics. MATERIALS AND METHODS: In order to study interactions of bile acids with transporters of intestinal bacteria, molecular-docking step was performed, using SwissDock web-service. For the purpose of comparison, two natural bile acids, cholic acid (CA) and deoxycholic acid (DCA), and one semi-synthetic bile acid, 12-monoketocholic acid (MKC), were studied in parallel. The free-binding energy was used as the main criterion for ranking ligands. RESULTS: Studied bile acids exhibited different binding affinities towards bacterial transporters with MKC showing the most prominent effect. For the majority of studied transporters, the estimated affinities of bile acids decreased in the following order: MKC-CA-DCA. Namely, 38.7% of examined transport proteins gave the lowest free-binding energy with MKC. The weak inverse relationship between number of hydrogen bonds and estimated free-binding energies was revealed. CONCLUSIONS: The predominant effect of MKC for the majority of studied transport proteins suggests that keto group at carbon 12 of the steroid core has a significant influence on the properties of MKC and consequently, on interactions with membrane transporters. Present findings might have a role in the prediction of potential influence of bile acids and probiotics on drug pharmacokinetics.

Analgesic effects of rosemary essential oil and its interactions with codeine and paracetamol in mice.

OBJECTIVE: The use of herbal medicinal products in the management of pain has been increasing steadily in recent years, often in combination with conventional analgesics, which can induce significant interactions. In traditional medicine, rosemary was used as mild analgesic, for relieving renal colic pain and dysmenorrhea. The aim of our study was to examine analgesic effects of rosemary essential oil and its pharmacodynamic interactions with codeine and paracetamol in mice. MATERIALS AND METHODS: The identification and quantification of chemical constituents of the essential oil isolated from air-dried aerial parts of rosemary were carried out by GC/FID and GC/MS. The hot plate test was performed on NMRI mice by placing them individually on hot plate and assessing their response to the thermal stimulus. RESULTS: In this research, we identified 29 chemical compounds of the studied rosemary essential oil, and the main constituents were 1,8-cineole, camphor, and α-pinene. Administration of investigated essential oil increased significantly the latency time of animal response to heat-induced pain between 20th and 50th minute of the test, when compared to saline-treated group. Rosemary essential oil in the dose of 20 mg/kg was shown to be more efficient than in the dose of 10 mg/kg, in combinations with both codeine and paracetamol. CONCLUSIONS: Our findings support the use of rosemary in the management of pain and indicate a therapeutic potential of rosemary essential oil in combination with analgesic drugs. The mechanisms involved in analgesic effects of rosemary essential oil and the potential influence on cytochromes and drug metabolism should be more in-depth investigated.

Acute toxic effects of single dose dacarbazine: hematological and histological changes in an animal model.

Treatment of advanced soft tissue sarcoma usually includes dacarbazine (DTIC), an alkylating agent that methylates DNA and is active during all phases of the cell cycle. Common side effects of DTIC include nausea, vomiting, impaired liver and kidney function, myelosuppression, and pneumonia. There are no accounts, however, of histological and hematological changes caused by DTIC. We investigated acute hematological and morphological changes in different organs and in tumors that were caused by a single dose of DTIC. Adult Syrian golden hamsters were inoculated with a suspension of tumorigenic baby hamster kidney (BHK) cells by subcutaneous injection. On day 14 after inoculation, doses of 1.4, 1.6, 1.8 or 2.0 g/m(2) DTIC were injected intraperitoneally into the hamsters. Hamsters in the control group were injected with physiological saline in the same way. Seven days after drug or saline injection the animals were sacrificed and samples of blood, heart, kidney, liver, lungs, spleen, small intestine and tumor were excised, processed and analyzed. Mitoses were counted using an ocular extension with engraved frame. Anemia, thrombocytopenia and leukocytosis were found in the control group of hamsters with fibrosarcoma, whereas animals with fibrosarcoma treated with DTIC developed anemia, thrombocytopenia and leukopenia. Severe pneumonia and moderate hepatitis were detected in all DTIC treated groups. Effects of DTIC on tumor cells included rounding and enlargement of nuclei and rarefaction of chromatin. The number of mitoses was reduced with increasing doses of DTIC. Hepatitis, myelosuppression, pneumonia, and dose-related inhibition of tumor cell proliferation were observed after a single dose of DTIC.

Ethical and legal aspects of oncogenomics.

The discovery of the genes and cellular pathways that play fundamental roles in several diseases, and the understanding of many diseases at a molecular level due to the advances in the field of genomics, have revolutionized the diagnosis, therapy and prevention of human diseases. Application of genetic testing in numerous medical fields, including pharmacogenomics and oncogenomics, raised numerous ethical questions and introduced legal instruments that are aimed at ensuring the appropriate protection of human research participants. For the effective development of human genomics and translation of novel, validated biomarkers into potentially useful clinical applications in personalized medicine, there is a need for clear ethical standards and principles in all phases of clinical research.

Pleiotropic functions of bile acids mediated by the farnesoid X receptor.

In addition to their well-established role in the digestion and absorption of dietary lipids, bile acids (BAs) are recognized as signalling molecules in a wide range of metabolic processes. Bile acids regulate their own metabolism and enterohepatic circulation by activating the farnesoid X receptor (FXR). BAs have been shown to affect lipid metabolism, to decrease levels of circulating triglycerides, improve hyperglycemia and insulin signalling, directly act on the arterial wall and protect hepatocytes against cholestatic liver injury. Given that BAs are an integrated part of the complex metabolic network regulated by FXR, acting as a major underlying pathway, specific therapeutic targeting of this nuclear receptor represents an attractive therapeutic approach for a wide range of disorders. During a phase II clinical trial, the administration of a semisynthetic BA derivative 6-ethyl-chenodeoxycholic acid (6-ECDCA) to patients with diabetes, non-alcoholic fatty liver disease (NAFLD) and primary biliary cirrhosis (PBC), led to encouraging results, despite side effects being observed in pre-clinical studies. Chemical manipulations of the side chain and the steroid nucleus of BAs could lead to the discovery of novel semisynthetic BA derivatives that are more specific and selective FXR activators.

Epidemiological characteristics of malignant ovarian tumors in Vojvodina.

PURPOSE: Ovarian cancer ranks 6th in relation to new cases of malignant diseases among females and 2nd concerning gynecological cancers. The purpose of this study was to determine the epidemiological situation of ovarian cancer in Vojvodina, Serbia. METHODS: In our study, we used a descriptive epidemiological method for the analysis of incidence and mortality of ovarian cancer in Vojvodina, based on the data of the Cancer Registry of Vojvodina. RESULTS: In the period 1987-2006, the average incidence rate of ovarian cancer was 15.28%/100,000 with an average annual increase of 1.15%; the average mortality rate for the same period was 9.24/100,000 with an average annual increase of 0.95%. The values of crude incidence rate (15.28/100,000) and standardized incidence rate (range 7.47 - 12.55/100,000) in Vojvodina correspond to the values in eastern and southern Europe. CONCLUSION: In the observed period of 20 years, the incidence and mortality rate indicate a tendency for increase, which can be characterized as an unfavorable epidemiological situation. New markers are being studied in order to find a solution for ovarian cancer screening.

Influence of bile acid derivates on tramadol analgesic effect in mice.

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.

Influence of the semisynthetic bile acid MKC on the ileal permeation of gliclazide in vitro in healthy and diabetic rats treated with probiotics.

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.

Anthracycline-based combined chemotherapy in the mouse model.

Our research was aimed at establishing if and how selenium (Se) ion, N-acetylcysteine (NAC), sodium salt of monoketocholic acid (MKH) and superoxide-dismutase (SOD), administered in the experimental animal model, could affect the possible cytotoxicity associated with anthracycline-based combined chemotherapy with doxorubicin, vincristine and prednisolone (DVP). The following biochemical parameters were investigated: the extent of lipid peroxidation (LPx), and the activity of peroxidase (Px), catalase (CAT), glutathione-peroxidase (GSHPx), and xanthine-oxidase (XOD). A statistical increase in LPx activity was obtained by SOD, MKH, DVPSe and DVPMKH. All chemotherapeutic agents reduced Px activity in a statistically significant manner. There was no statistical significance for the results regarding the effects of the administered substances on GSHPx activity. The results for DVP, SOD, MKH, DVPSOD, DVPSe and DVPMKH showed reduced XOD activity which was statistically significant, which was lowest in the case of MKH, while NAC and Se reduced the activity of this enzyme but statistically non significant. NAC, Se, DVP, MKH and DVPMKH caused a reduction in CAT activity, while DVPSOD and DVPSe caused an increase of the latter.

Bioavailability and hypoglycemic activity of the semisynthetic bile acid salt, sodium 3alpha,7alpha-dihydroxy-12-oxo-5beta-cholanate, in healthy and diabetic rats.

Previous studies in our laboratory have shown that the semisynthetic bile acid derivative, sodium 3alpha,7alpha-dihydroxy-12-oxo-5beta-cholanate (MKC), has hypoglycemic activity. The aim of this study was to investigate the relationship between the pharmacokinetics and hypoglycemic activity of MKC in healthy and diabetic rats. Groups of healthy and alloxan-induced diabetic rats were dosed intravenously (i.v.) and orally with MKC (4 mg/kg). Blood samples were taken before administration of the dose and at 20, 40, 60, 80, 120, 150, 180, 210 and 240 minutes post-dose. MKC serum concentration was measured by HPLC, and pharmacokinetic parameters determined using the WinNonlin program. The absolute bioavailability of MKC was found to be low in healthy and diabetic rats (29 and 23% respectively) and was not significantly different between the two groups. Mean residence time (MRT), volume of distribution (Vd) and half-life (t1/2) of MKC after oral administration were significantly lower in diabetic than in healthy rats (21, 31 and 29% respectively). After the i.v. dose, the change in blood glucose concentration was not significant in either healthy or diabetic rats. After the oral dose, the decrease in blood glucose concentration was significant, reaching a maximum decrease from baseline of 24% in healthy rats and 15% in diabetic rats. The results suggest that a first-pass effect is crucial for the hypoglycemic activity of MKC, indicating that a metabolite of MKC and/or interference with metabolism and glucose transport is responsible.

Structure and origin of bile acids: an overview.

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.

Biosynthesis of bile acids in mammalian liver.

The biosynthesis of bile acids in mammalian liver and its regulation, together with the physiological role of bile acids, are reviewed in this article. Bile acids are biosynthesized from cholesterol in hepatocytes. Several steps are involved including epimerisation of the 3beta-hydroxyl group, reduction of the delta4 double bond to the 5beta-H structural arrangement, introduction of alpha-hydroxyl groups at C7 or C7 and C12 and, finally, oxidative degradation of the side chain by three carbon atoms. This gives the primary bile acids, cholic and chenodeoxycholic acids. Cholesterol-7alpha-hydroxylation is the rate determining step in the biosynthesis of cholic and chenodeoxycholic acids. Feedback regulation of cholesterol biosynthesis occurs by various mechanisms including termination of the synthesis of specific cytochromes P-450, modulation of specific cytosol proteins, short-term changes in the process of phosphorylation-dephosphorylation and changes in the capacity of the cholesterol pool as a substrate. Prior to being exported from the liver, bile acids are conjugated with glycine and taurine to produce the bile salts. After excretion into the intestinal tract, primary bile acids are partly converted to secondary bile acids, deoxycholic and lithocholic acids, by intestinal microorganisms. The majority of bile acids is absorbed from the intestinal tract and returned to the liver via the portal blood, so that only a small fraction is excreted in the feces. Bile acids returned to the liver can be reconjugated and reexcreted into the bile in the process of enterohepatic recycling. In addition to the physiological function of emulsifying lipids in the intestinal tract, bile acids are particularly important in respect of their ability to dissolve and transport cholesterol in the bile.

Isolation and determination of bile acids.

In this article, the methods of isolation and determination of bile acids are reviewed. Methods for separation of bile acids from cattle and pig bile are given in detail. Isolation of a mixture of cholic acid and deoxycholic acids from cattle bile and their subsequent purification are described. The isolation and purification of hyodeoxycholic acid and other components of pig bile are also included. Methods for the determination of bile acids in various biological samples are reviewed, including enzyme assays, radioimmunoassay, enzyme immunoassay and chromatographic methods. Among chromatographic methods, separation and determination of bile acids by thin-layer chromatography, gas chromatography and high performance liquid chromatography are reviewed. Particular attention is given to the use of high performance liquid chromatography since this has recently been the most commonly applied method for the separation and determination of bile acids.

Pharmacology of bile acids and their derivatives: absorption promoters and therapeutic agents.

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.