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Dietary and microbial oxazoles induce intestinal inflammation by modulating aryl hydrocarbon receptor responses.

Shankar S. Iyer, Thomas Gensollen, Amit Gandhi, Sungwhan F. Oh, Joanna F. Neves, Frederic Collin, Richard Lavin, Carme Serra, Jonathan Glickman, Punyanganie S. A. de Silva, R. Balfour Sartor, Gurdyal Besra, Russell Hauser, , Anthony Maxwell, Amadeu Llebaria, Richard S. Blumberg

Cell (2018) 173(5) p1123–1134.e11

 Genome-wide association studies have identified risk loci associated with the development of inflammatory bowel disease, while epidemiological studies have emphasized that pathogenesis likely involves host interactions with environmental elements whose source and structure need to be defined. Here, we identify a class of compounds derived from dietary, microbial, and industrial sources that are characterized by the presence of a five-membered oxazole ring and induce CD1d-dependent intestinal inflammation. We observe that minimal oxazole structures modulate natural killer T cell-dependent inflammation by regulating lipid antigen presentation by CD1d on intestinal epithelial cells (IECs). CD1d-restricted production of interleukin 10 by IECs is limited through activity of the aryl hydrocarbon receptor (AhR) pathway in response to oxazole induction of tryptophan metabolites. As such, the depletion of the AhR in the intestinal epithelium abrogates oxazole-induced inflammation. In summary, we identify environmentally derived oxazoles as triggers of CD1d-dependent intestinal inflammatory responses that occur via activation of the AhR in the intestinal epithelium.

 

Synthesis, characterization, and self-assembly of a tetrathiafulvalene (TTF)-triglycyl derivative

Pérez-Rentero, S., Eritja, R., Häring, M., Saldías, C., Díaz, D.D.

Applied Sciences (Switzerland), 8 (5), art. no. 671, 2018

 In this work, we describe the synthesis, characterization, and self-assembly properties of a new tetrathiafulvalene (TTF)–triglycyl low-molecular-weight (LMW) gelator. Supramolecular organogels were obtained in various solvents via a heating–cooling cycle. Critical gelation concentrations (CGC) (range ˜ 5–50 g/L) and thermal gel-to-sol transition temperatures (Tgel) (range ˜ 36–51 °C) were determined for each gel. Fourier transform infrared (FT-IR) spectroscopy suggested that the gelator is also aggregated in its solid state via a similar hydrogen-bonding pattern. The fibrillar microstructure and viscoelastic properties of selected gels were demonstrated by means of field-emission electron microscopy (FE-SEM) and rheological measurements. As expected, exposure of a model xerogel to I2 vapor caused the oxidation of the TTF unit as confirmed by UV-vis-NIR analysis. However, FT-IR spectroscopy showed that the oxidation was accompanied with concurrent alteration of the hydrogen-bonded network.

 

The role of SeDeM for characterizing the active substance and polyvinyilpyrrolidone eliminating metastable forms in an oral lyophilizate—A preformulation study

Borges, P.F., García-Montoya, E., Pérez-Lozano, P., Jo, E., Miñarro, M., Manich, A., Suñé-Negre, J.M.

 PLoS ONE, 13 (4), art. no. e0196049, 2018

 A preformulation study of an oral lyophilisate with cetirizine dihydrochloride (CTZ) as active ingredient, mannitol and PVP K30 as bulking agents is presented. CTZ shown a humidity content of 0.150% and a spontaneous hygroscopicity of 0.200% (both determined by SeDeM diagram), demonstrating an adequate stability behavior in solid form. A design of experiments (DoE) performed with both mannitol and PVP K30, followed by a simple factorial design (32) has determined the optimum combination of excipients and CTZ, and showed that a higher proportion of PVP K30 was able to prevent metastable forms generated by mannitol.

 

Ovarian function modulates the effects of long-chain polyunsaturated fatty acids on the mouse cerebral cortex

Herrera, J.L., Ordoñez-Gutierrez, L., Fabrias, G., Casas, J., Morales, A., Hernandez, G., Acosta, N.G., Rodriguez, C., Prieto-Valiente, L., Garcia-Segura, L.M., Alonso, R., Wandosell, F.G.

 Frontiers in Cellular Neuroscience, 12, art. no. 103, 2018

 Different dietary ratios of n−6/n−3 long-chain polyunsaturated fatty acids (LC-PUFAs) may alter brain lipid profile, neural activity, and brain cognitive function. To determine whether ovarian hormones influence the effect of diet on the brain, ovariectomized and sham-operated mice continuously treated with placebo or estradiol were fed for 3 months with diets containing low or high n−6/n−3 LC-PUFA ratios. The fatty acid (FA) profile and expression of key neuronal proteins were analyzed in the cerebral cortex, with intact female mice on standard diet serving as internal controls of brain lipidome composition. Diets containing different concentrations of LC-PUFAs greatly modified total FAs, sphingolipids, and gangliosides in the cerebral cortex. Some of these changes were dependent on ovarian hormones, as they were not detected in ovariectomized animals, and in the case of complex lipids, the effect of ovariectomy was partially or totally reversed by continuous administration of estradiol. However, even though differential dietary LC-PUFA content modified the expression of neuronal proteins such as synapsin and its phosphorylation level, PSD-95, amyloid precursor protein (APP), or glial proteins such as glial fibrillary acidic protein (GFAP), an effect also dependent on the presence of the ovary, chronic estradiol treatment was unable to revert the dietary effects on brain cortex synaptic proteins. These results suggest that, in addition to stable estradiol levels, other ovarian hormones such as progesterone and/or cyclic ovarian secretory activity could play a physiological role in the modulation of dietary LC-PUFAs on the cerebral cortex, which may have clinical implications for post-menopausal women on diets enriched with different proportions of n−3 and n−6 LC-PUFAs.

 

New approach based on immunochemical techniques for monitoring of selective estrogen receptor modulators (SERMs) in human urine

Salvador, J.-P., Vila-Roca, E., Monfort, N., Ventura, R., Marco, M.-P.

Journal of Pharmaceutical and Biomedical AnalysisVolume 156, 15 July 2018, Pages 147-152

 Antiestrogenic compounds such as tamoxifen, toremifen and chlomifen are used illegally by athletes to minimize physical impacts such as gynecomastia resulting from the secondary effects of anabolic androgenic steroids, used to increase athletic efficiency unlawfully. The use of these compounds is banned by the World Anti-Doping Agency (WADA) and controls are made through analytical methodologies such as HPLC–MS/MS, which do not fulfil the sample throughput requirements. Moreover, compounds such as tamoxifen are also used to treat hormone receptor-positive breast cancer (ER?+?).Therapeutic drug monitoring (TDM) of tamoxifen may also be clinically useful for guiding treatment decisions. An accurate determination of these drugs requires a solid phase extraction of patient serum followed by HPLC–MS/MS. In the context of an unmet need of high-throughput screening (HTS) and quantitative methods for antiestrogenic substances we have approached the development of antibodies and an immunochemical assay for the determination of these antiestrogenic compounds. The strategy applied has taken into consideration that these drugs are metabolized and excreted in urine as the corresponding 4-hydroxylated compounds. A microplate-based ELISA procedure has been developed for the analysis of these metabolites in urine with a LOD of 0.15, 0.16 and 0.63?µg/L for 4OH-tamoxifen, 4OH-toremifen and 4OH-clomifen, respectively, much lower than the MRPL established by WADA (20?µg/L).

 

Enzyme-linked immunosorbent assays for therapeutic drug monitoring coumarin oral anticoagulants in plasma

Salvador, J.-P., Tassies, D., Reverter, J.-C., Marco, M.-P.

Analytica Chimica Acta,2018

 The development of high-throughput immunochemical assays to assist on precision medicine for patients treated with coumarin oral anticoagulants (OA) is reported. The assays are able to quantitate Warfarin (W) and/or Acenocoumarol (ACL) directly in plasma samples without any previous sample pretreatment. The detectabilities (W, 3.52?±?2.25?nM and ACL, 1.56?±?0.64?nM) and the working ranges achieved (W, 1.19?±?0.73 to 12.05?±?2.99?nM and ACL 0.63?±?0.20 to 10.19?±?6.69?nM) are within the therapeutic levels usually found in patients treated with these drugs. The assays are specific with only cross-recognition of 4'-NH2-ACL on the ACL ELISA, which is one of the main metabolites of this drug. Moreover, accuracy studies performed with blind spiked samples show very good correlation between the spiked and the measured concentrations. Finally, a small clinical pilot study has been performed analyzing 96 plasma samples from treated and untreated patients, showing that the assay is able to quantitate ACL. The results obtained allow envisaging the possibility to use these assays for pharmacokinetic studies, dosage assessment or therapeutic drug monitoring.

 

Vesicular nanostructures composed of oleic acid and phosphatidylcholine:Effect of pH and molar ratio

K. Talló, V. Moner, M. De Cabo, M. Cócera, O. López

Chemistry and Physics of Lipids 213 (2018) 96–101

Phospholipids and fatty acids are the main building blocks of biological membranes. Oleic acid is a monounsaturated omega-9 fatty acid commonly found in many natural sources. Its characteristic kinked structure grants this molecule with a great number of biological properties. To better understand the role that this kind of fatty acids play into phospholipid membranes, nanostructured systems formed with hydrogenated soy phosphatidylcholine and oleic acid were studied in this work by means of cryo-electron microscopy, dynamic light scattering and differential scanning calorimetry. Differences concerning size, morphology and phase behavior were found when those systems were prepared at different conditions of pH and molar ratio between both compounds. Broadly, it was seen how alkaline mediums and high proportions of oleic acid reduced the size of the structures and increased the fluidity of the membranes. The ease of preparation of these lipid systems, and the response to pH suggests a future use of these systems as model membranes or delivery systems.

 

siRNA Modified with 2'-Deoxy-2'-C-methylpyrimidine Nucleosides

Dellafiore, M., Aviñó, A., Alagia, A., Montserrat, J.M., Iribarren, A.M., Eritja, R.

 ChemBioChem, 2018

 (2'S)-2'-Deoxy-2'-C-methyluridine and (2'R)-2'-deoxy-2'-C-methyluridine were incorporated in the 3'-overhang region of the sense and antisense strands and in positions 2 and 5 of the seed region of siRNA duplexes directed against Renilla luciferase, whereas (2'S)-2'-deoxy-2'-C-methylcytidine was incorporated in the 6-position of the seed region of the same constructions. A dual luciferase reporter assay in transfected HeLa cells was used as a model system to measure the IC50 values of 24 different modified duplexes. The best results were obtained by the substitution of one thymidine unit in the antisense 3'-overhang region by (2'S)- or (2'R)-2'-deoxy-2'-C-methyluridine, reducing IC50 to half of the value observed for the natural control. The selectivity of the modified siRNA was measured, it being found that modifications in positions 5 and 6 of the seed region had a positive effect on the ON/OFF activity.

 

DNA-based nanoscaffolds as vehicles for 5-fluoro-2'-deoxyuridine oligomers in colorectal cancer therapy

Jorge, A.F., Aviñó, A., Pais, A.A.C.C., Eritja, R., Fàbrega, C.

 Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy, 196, pp. 185-195. 2018

 Fluoropyrimidines, such as 5-fluorouracil (5-FU) and related prodrugs, are considered one of the most successful agents in the treatment of colorectal cancer, yet poor specificity and tumor cell resistance remain the major limiting bottlenecks. Here, we exploited for the first time the ability of two DNA nanoscaffolds, a DNA tetrahedron (Td) and rectangle DNA origami, to incorporate 5-fluoro-2'-deoxyuridine (FdUn) oligomers. In addition, cholesterol moieties were synthetically attached to Td and DNA origami staples to enhance cellular uptake. DNA nanostructures functionalized with FdUn exhibited an enhanced cytotoxicity and higher ability to trigger apoptosis in colorectal cancer cells relative to conventional 5-FU and FdU, especially having cholesterol as an internalization helper. The cholesterol content mostly correlates with the increase of the FdUn nanostructure cytotoxicity. DNA nanoscaffolds bearing FdUn were able to circumvent the low sensitivity of colorectal cancer cells towards 5-FU. Both DNA nanostructures attained a comparable cytotoxic effect yet Td displays higher antiproliferative action. The ability to reduce the proliferation of cancer cells is mainly related to the concentration of DNA nanostructures. The present work suggests that self-assembled DNA nanoparticles are privileged vehicles for delivering fluoropyrimidines, opening new avenues to the development of promising therapeutics for cancer treatment.

 


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