Both pre- and post-synaptic effects of trace amines have been demonstrated. The putative intracellular location of Trace Amine-Associated Receptors necessitate that membrane transport processes be present in order for post-synaptic effects to occur. Here we examine the ability of trace amines to cross synthetic (Fluorosomes) and native (synaptosomes) lipid bilayer membranes. Trace amines readily crossed Fluorosome membranes by simple diffusion, p-tyramine (P = 0.01) and tryptamine (P = 0.0004) showing significantly faster diffusion than dopamine and 5-HT, respectively, with diffusion half-lives of 13.5 ± 4.1 (p-tyramine) and 6.8 ± 0.7 seconds (tryptamine). Similarly, release of [(3) H]p-tyramine and [(3) H]2-phenylethylamine from pre-loaded synaptosomes occurred significantly quicker than did [(3) H]dopamine (P = 0.0001), with half lives of 38.9 (p-tyramine), 7.8 (2-phenylethylamine) and 133.6 seconds (dopamine). This was, however, significantly slower than the diffusion mediated passage across Fluorosome membranes (P = 0.0001), suggesting a role for transporters in mediating trace amine release. Further, a pronounced shoulder region was observed in the synaptosome [(3) H]p-tyramine release curve, suggesting that multiple processes regulate release. No such shoulder region was present for [(3) H]dopamine release. Surprisingly, both [(3) H]p-tyramine (P = 0.001) and [(3) H]2-phenylethylamine (P = 0.0001) release from synaptosomes was significantly decreased under depolarizing conditions. As expected, depolarization significantly increased [(3) H]dopamine release. The data presented indicate that the release of p-tyramine and 2-phenylethylamine from neuronal terminals occurs by a different mechanism than dopamine, and does not involve classical exocytosis. The data are consistent with an initial release of trace amines by simple diffusion, followed by an activity-dependent regulation of synaptic levels via one or more transporter proteins.

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Bile acids are endogenous ligands of nuclear receptors pregnane X (PXR) and farnesoid X (FXR). PXR and FXR regulate pathways that are impaired in inflammatory bowel disease (IBD). Decreases in PXR and FXR activity are documented in IBD; however reasons for this are unknown. We aimed to assess the effect of Crohn's disease (CD) on the plasma bile acid composition in vivo and the resultant impact on PXR and FXR activation. A cross-sectional study evaluated the plasma concentrations of 12 bile acids in addition to 4β-hydroxycholesterol (4βOHC), an in vivo probe of the PXR target-gene cytochrome 3A4 (CYP3A4) and the FXR target-gene, fibroblast growth factor (FGF) 19 in individuals with (n = 74) and without (n = 71) CD. An in vitro model was used to assess the impact of CD-specific changes in the plasma bile acid composition on PXR and FXR activation. Decreases in glycochenodeoxycholic acid, taurocholic acid and lithocholic acid were seen in CD with increases in glycodeoxycholic acid and glycocholic acid relative to the total plasma bile acid profile. In vitro, increasing concentrations of bile acids applied in the same ratio as seen in the study cohorts resulted in decreased activation of both PXR and FXR in the CD model. In vivo, plasma 4βOHC (CD = 18.68 ng/ml ± 13.02 ng/ ml, non-CD = 46.38 ng/ml ± 40.70 ng/ml, p ≤ 0.0001) and FGF19 (CD = 0.276 pg/L ± 0.189 pg/L, non-CD = 0.485 pg/L ± 0.42 pg/L, p = 0.0002) concentrations were lower in CD versus controls. Ultimately, CD-specific changes in the plasma bile acid composition lead to reduced activation of FXR and pXR target genes in vitro and in vivo. Bile acids are a collection of dynamic "acidic steroids", produced by the liver 1. In health, physiologic concentrations of bile acids differ amongst the various compartments with the highest concentrations seen in the gallbladder (300 mmol/L) with decreasing concentrations in the hepatic canaliculi (20-50 mmol/L) and intestine (10 mmol/L) 2. The role of bile acids in vivo extends beyond simple lipid absorption and metabolism and encompasses several key physiologic processes paramount to humans. These include regulation of xenobiotic exposure and drug metabolism, inflammatory pathways, and intestinal barrier function, mediated mainly through master regulators and transcription factors known as nuclear receptors 3-6. Interestingly, synthesis and disposition of bile acids are tightly controlled by nuclear receptors, bile acid transporters, enzymes, and intestinal bacteria. To date, more than 48 members of the nuclear receptor family have been identified 7. Nuclear receptors, pregnane X (PXR) and farnesoid X (FXR) are important to drug metabolism and transport pathways and are increasingly recognized as being relevant to inflammatory bowel disease (IBD; Crohn's disease, CD; ulcerative colitis, UC) pathogenesis 5,8-10. Bile acids are important endogenous ligands of PXR and FXR, with varying degrees of potency 3,11. PXR is most robustly activated by free or conjugated lithocholic acid (LCA) and deoxycholic acid (DCA), while FXR...

Evidence from the literature suggests that dietary flaxseed lignans have the ability to modulate inflammation, which is recognized as the underlying basis of multiple chronic human diseases in older adults. Our objective was to determine the effects of oral lignan supplementation on biochemical and functional indicators of inflammation as well as safety and tolerability in older healthy adults. We designed a randomized, double-blind, placebo-controlled clinical trial in older healthy adults (60-80 years) to assess flaxseed lignan-enriched complex (∼38% secoisolariciresinol diglucoside [SDG]; 600 mg SDG dose) oral supplementation effects on biochemical and functional indicators of inflammation and safety and tolerability in older healthy adults after 6 months of once-daily oral administration. The clinical trial confirmed that plasma concentration of total flaxseed lignans (free and conjugated forms) secoisolariciresinol (SECO), enterodiol (ED), and enterolactone (ENL) were significantly associated with daily oral supplementation of flaxseed lignan-enriched complex (p < 0.05). A significant decrease in systolic blood pressure (SBP; from a mean of 155 ± 13 mm Hg at baseline to 140 ± 11 mm Hg at 24 weeks) was observed in lignan-supplemented participants stratified into an SBP ≥140 mm Hg subcategory (p = 0.04). No differences were found between treatment or placebo groups in terms of cognition, pain, activity, physical measurements (calf, waist, and upper arm circumstances), and grip strength. With respect to blood inflammatory markers, lipid profiles, and biochemical parameters, no significant differences were found between treatment and placebo groups at the end of the 6-month supplementation. No adverse effects were reported during supplementation. These data further support the safety and tolerability of long-term flaxseed lignan-enriched complex supplementation in older adults and identify an ability to favorably modulate SBP, an important risk factor in cardiovascular disease.

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A simple, rapid and validated high performance liquid chromatography method with UV detection for the quantification of an opioid agonist, fentanyl (FEN), in rat plasma was developed. The assay procedure involved chromatographic separation using a ZIC-HILIC SeQUANT column (250 × 4.6 mm, i.d., 5 µm) and a mobile phase of acetonitrile and acetate buffer (pH 3.4, 20 mM) of ratio (= 65:35, v/v) at a flow rate of 1.2 mL/min and detection wavelength of 201 nm. Plasma sample (100 μL) pretreatment was based on simple deprotienization by acetonitrile spiked with clonidine as an internal standard (I.S.) of 20 ng/mL followed by extraction with tert-butyl methyl ether and centrifugation. The organic layer was evaporated under N 2 gas and reconstituted with 100 μL of acetate buffer (pH 3.4, 20 mM), and 50-μL portions of reconstituted sample were injected onto the column. Sample analysis including sample pretreatment was achieved within 35 min. Calibration curve was linear (r ≥ 0.998) from 5 to 100 ng/mL. Both intra-and inter-day assay precisions that are presented through R.S.D were lower than 12.6% for intra-day and lower than 12.0% for inter-day assessment. Limit of detection was 0.8 ng/mL at S/N of 3. This method was omitting the use of expensive solid phase extraction and time consuming liquid extraction procedures. Moreover, the present method was successfully applied to study pharmacokinetic parameters of FEN after intraperitoneal administration to male Wistar rat. Pharmacokinetic parameters estimated by using moment analysis were; T 1/2 198.3 ± 44.7 min, T max 28.3 ± 2.9 min and AUC 0-180 15.6 ± 2.9 (×10 2 ) ng·min/mL.

Pharmacogenetic research has resulted in the identification of a multitude of genetic variants that impact drug response or toxicity. These polymorphisms are mostly common and have been included as actionable information in the labels of numerous drugs. In addition to common variants, recent advances in Next Generation Sequencing (NGS) technologies have resulted in the identification of a plethora of rare and population-specific pharmacogenetic variations with unclear functional consequences that are not accessible by conventional forward genetics strategies. In this review, we discuss how comprehensive sequencing information can be translated into personalized pharmacogenomic advice in the age of NGS. Specifically, we provide an update of the functional impacts of rare pharmacogenetic variability and how this information can be leveraged to improve pharmacogenetic guidance. Furthermore, we critically discuss the current status of implementation of pharmacogenetic testing across drug development and layers of care. We identify major gaps and provide perspectives on how these can be minimized to optimize the utilization of NGS data for personalized clinical decision-support.

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