Seojeong Park, Til Bahadur Thapa Magar, Tara Man Kadayat, Hwa Jong Lee, Ganesh Bist, Aarajana Shrestha, Eung-Seok Lee, Youngjoo Kwon
Novel series of conformationally constrained 2,4-chloro- and hydroxy-substituted diphenyl benzofuro[3,2-b]pyridines were rationally designed and synthesized. Their biological activities were evaluated for topoisomerase I and II inhibitory activity, and antiproliferative activity against several human cancer cell lines for the development of novel anticanceragents. Most of the compounds with phenol moiety at 4-position of central pyridine exhibited significant dual topoisomerase I and II inhibitory activities, and strong antiproliferative activity in low micromolar range. Structure activity relationship study suggested that phenol moiety at 4-position of the central pyridine regardless of chlorophenyl moiety at 2-position of the central pyridine has an important role in dual topoisomerase inhibitory activity as well as antiproliferative activity. For investigation of mode of action for compound 14 which displayed the most strong dual topoisomerase I and II inhibitory activity and antiproliferative activity against HCT15 cell, we performed cleavable complex assay, band depletion assay, comet assay, and competitive EtBr displacement assay. Compound 14 functioned as non-intercalative catalytic topo I and II dual inhibitor. In addition, compound 14 induced apoptosisin HCT15 cells through increase of Bax, decrease of Bcl-2 and increase of PARP cleavage.
The MS analysis was carried out using Advion Expression® CMS.
Alba Noël,Solenn Ferron, Isabelle Rouaud,Nicolas Gouault, Jean-Pierre Hurvois, Sophie Tomasi
Actinobacteria are well known for their potential in biotechnology and their production of metabolites of interest. Lichens are a promising source of new bacterial strains, especially Actinobacteria, which afford a broad chemical diversity. In this context, the culture medium of the actinobacterium Nocardia ignorata, isolated from the terrestrial lichen Collema auriforme, was studied. The strain was cultivated in a BioFlo 115 bioreactor, and the culture medium was extracted using an XAD7HP resin. Five known diketopiperazines: cyclo (l-Pro-l-OMet) (1), cyclo (l-Pro-l-Tyr) (2), cyclo (d-Pro-l-Tyr) (3), cyclo (l-Pro-l-Val) (4), cyclo (l-Pro-l-Leu) (5), and one auxin derivative: indole-carboxaldehyde (8) were isolated, along with two new brominated diketopiperazines: cyclo (d-Pro-l-Br-Tyr) (6) and cyclo (l-Pro-l-Br-Tyr) (7). Structure elucidation was performed using HRMS and 1D and 2D NMR analysis, and the synthesis of compounds 6 and 7 was carried out in order to confirm their structure.
The MS analysis was carried out using Advion Expression® CMS.
Michael Lückmann, Roxana-Maria Amarandi, Natalia Papargyri, Mette H. Jakobsen, Elisabeth Christiansen, Lars J. Jensen, Aurel Pui, Thue W. Schwartz, Mette M. Rosenkilde, Thomas M. Frimurer
The human cytomegalovirus-encoded G protein-coupled receptor US28 is a constitutively active receptor, which can recognize various chemokines. Despite the recent determination of its 2.9 Å crystal structure, potent and US28-specific tool compounds are still scarce. Here, we used structural information from a refined US28:VUF2274 complex for virtual screening of >12 million commercially available small molecule compounds. Using a combined receptor- and ligand-based approach, we tested 98 of the top 0.1% ranked compounds, revealing novel chemotypes as compared to the ~1.45 million known ligands in the ChEMBL database. Two compounds were confirmed as agonist and inverse agonist, respectively, in both IP accumulation and Ca2+mobilization assays. The screening setup presented in this work is computationally inexpensive and therefore particularly useful in an academic setting as it enables simultaneous testing in binding as well as in different functional assays and/or species without actual chemical synthesis.
The LC/MS analysis was carried out using Advion Expression® CMS.
Aarajana Shrestha, HyeJin Oh, Mi Jin Kim, Nirmala Tilija Pun, Til Bahadur Thapa Magar, Ganesh Bist, Hongseok Choi, Pil-Hoon Park, Eung-Seok Lee
As a continuous effort to discover new potential anti-inflammatory agents, we systematically designed and synthesized sixty-one 2-benzylidene-1-indanone derivatives with structural modification of chalcone, and evaluated their inhibitory activity on LPS-stimulated ROS production in RAW 264.7 macrophages. Systematic structure-activity relationship study revealed that hydroxyl group in C-5, C-6, or C-7 position of indanone moiety, and ortho-, meta-, or para-fluorine, trifluoromethyl, trifluoromethoxy, and bromine functionalities in phenyl ring are important for inhibition of ROS production in LPS-stimulated RAW 264.7 macrophages. Among all the tested compounds, 6-hydroxy-2-(2-(trifluoromethoxy) benzylidene)-2,3-dihydro-1H-inden-1-one (compound 44) showed the strongest inhibitory activity of ROS production. Further studies on the mode of action revealed that compound 44 potently suppressed LPS-stimulated ROS production via modulation of NADPH oxidase. The findings of this work could be useful to design 2-benzylidene-indanone based lead compounds as novel anti-inflammatory agents.
The MS analysis was carried out using Advion Expression® CMS.
Christian Hoppmann, Allison Wong, Bing Yang, Shuwei Li, Tony Hunter, Kevan M. Shokat, Lei Wang
Access to phosphoproteins with stoichiometric and site-specific phosphorylation status is key to understanding the role of protein phosphorylation. Here we report an efficient method to generate pure, active phosphotyrosine-containing proteins by genetically encoding a stable phosphotyrosine analog that is convertible to native phosphotyrosine. We demonstrate its general compatibility with proteins of various sizes, phosphotyrosine sites and functions, and reveal a possible role of tyrosine phosphorylation in negative regulation of ubiquitination.
The MS analysis was carried out using Advion Expression® CMS ESI.
Harrison C. Daly, Gonzalo Sampedro, Corentin Bon, Dan Wu, Ghazi Cahill, Roman A. Cahill, Donal F. O’Shea
The use of near-infrared fluorescence for in vivo research and intraoperative clinical imaging is rapidly expanding, with new applications being proposed and developed. While imaging hardware and software have significantly progressed in recent times, the molecular fluorescent agents remain a limiting factor. In this report, the design, synthesis, photophysical characterization and bio-medical imaging assessment of two new NIR-fluorophores based on the BF2-azadipyrromethene fluorophore class are described. Inclusion of dimethylamino substituents on these BF2-azadipyrromethene probes results in very large bathochromic shifts with photophysical measurements showing absorption and emission maxima between 757 and 818 nm within the desired NIR spectra region. Testing of the probes shows that they are suitable for fluorescence imaging with both research and clinical instrumentation. Preclinical imaging assessment shows their suitability as fluorescent markers (tattoos) of lesions for intraoperative identification and lymphatic mapping in ex vivo human colonic tissue. These new clinical wavelength-compatible fluorophores may contribute towards the on-going expansion of medical uses for NIR-fluorescence.
The LC/MS analysis was carried out using Advion Expression® CMS.
Alice Gadea, Pierre Le Pogam, Grichka Biver, Joël Boustie, Anne-Cécile Le Lamer, Le Dévéhat Françoise, Maryvonne Charrier
Notodiscus hookeri is the only representative of terrestrial gastropods on Possession Island and exclusively feeds on lichens. The known toxicity of various lichen metabolites to plant-eating invertebrates led us to propose that N. hookeri evolved means to protect itself from their adverse effects. To validate this assumption, the current study focused on the consumption of two lichen species: Usnea taylorii and Pseudocyphellaria crocata. A controlled feeding experiment was designed to understand how the snail copes with the unpalatable and/or toxic compounds produced by these lichen species. The occurrence of two snail ecophenotypes, represented by a mineral shell and an organic shell, led to address the question of a metabolic response specific to the phenotype. Snails were fed for two months with one of these lichens and the chemical profiles of biological samples of N. hookeri (i.e., crop, digestive gland, intestine, and feces) were established by HPLC-DAD-MS and compared to that of the lichens. N. hookeri appears as a generalist lichen feeder able to consume toxic metabolite-containing lichens, independently of the ecophenotype. The digestive gland did not sequester lichen metabolites. The snail metabolism might be based on four non-exclusive processes according to the concerned metabolites (avoidance, passive transport, hydrolysis, and excretion).
The LC/MS analysis was carried out using Advion Expression® CMS ESI.
M.R. Chae, S.J. Kang, K.P. Lee, B.R. Choi, H.K. Kim, J.K. Park, C.Y. Kim, S.W. Lee
Onion (Allium cepa L.) and quercetin protect against oxidative damage and have positive effects on multiple functional parameters of spermatozoa, including viability and motility. However, the associated underlying mechanisms of action have not yet been identified. The aim of this study was to investigate the effect of onion peel extract (OPE) on voltage-gated proton (Hv1) channels, which play a critical role in rapid proton extrusion. This process underlies a wide range of physiological processes, particularly male fertility. The whole-cell patch-clamp technique was used to record the changes in Hv1 currents in HEK293 cells transiently transfected with human Hv1 (HVCN1). The effects of OPE on human sperm motility were also analyzed. OPE significantly activated the outward-rectifying proton currents in a concentration-dependent manner, with an EC50 value of 30 μg/mL. This effect was largely reversible upon washout. Moreover, OPE induced an increase in the proton current amplitude and decreased the time constant of activation at 0 mV from 4.9 ± 1.7 to 0.6 ± 0.1 sec (n = 6). In the presence of OPE, the half-activation voltage (V1/2 ) shifted in the negative direction, from 20.1 ± 5.8 to 5.2 ± 8.7 mV (n = 6), but the slope was not significantly altered. The OPE-induced current was profoundly inhibited by 10 μm Zn2+ , the most potent Hv1 channel inhibitor, and was also inhibited by treatment with GF109203X, a specific protein kinase C (PKC) inhibitor. Furthermore, sperm motility was significantly increased in the OPE-treated groups. OPE exhibits protective effects on sperm motility, at least partially via regulation of the proton channel. Moreover, similar effects were exerted by quercetin, the major flavonoid in OPE. These results suggest OPE, which is rich in the potent Hv1 channel activator quercetin, as a possible new candidate treatment for human infertility.
The LC/MS analysis was carried out using Advion Expression® CMS.
Til Bahadur Thapa Magar, Tara Man Kadayat, Hye Jin Oh, Pil-Hoon Park, Eun-Seok Lee
Chromanone-containing compounds have been reported to possess several important biological activities. As a part of our continuing effort for discovering potent anti-inflammatory agents, a series of halogen-containing 3-benzylidenechroman-4-ones (1–15) were synthesized, and evaluated for their inhibitory effect on lipopolysaccharide (LPS)-stimulated reactive oxygen species (ROS) production in RAW 264.7 macrophages. Compounds 4 and 10 exhibited significant inhibitory activity (IC50 = 5.09 ± 1.27 and 5.11 ± 0.51 μM, respectively) against LPS-stimulated ROS production in RAW 264.7 macrophages.
The LC/MS analysis was carried out using Advion Expression® CMS ESI.
Raymond Glahn, Elad Tako, Jonathan Hart, Jere Haas, Mercy Lung’aho, Steve Beebe
This paper represents a series of in vitro iron (Fe) bioavailability experiments, Fe content analysis and polyphenolic profile of the first generation of Fe biofortified beans (Phaseolus vulgaris) selected for human trials in Rwanda and released to farmers of that region. The objective of the present study was to demonstrate how the Caco-2 cell bioassay for Fe bioavailability can be utilized to assess the nutritional quality of Fe in such varieties and how they may interact with diets and meal plans of experimental studies. Furthermore, experiments were also conducted to directly compare this in vitro approach with specific human absorption studies of these Fe biofortified beans. The results show that other foods consumed with beans, such as rice, can negatively affect Fe bioavailability whereas potato may enhance the Fe absorption when consumed with beans. The results also suggest that the extrinsic labelling approach to measuring human Fe absorption can be flawed and thus provide misleading information. Overall, the results provide evidence that the Caco-2 cell bioassay represents an effective approach to evaluate the nutritional quality of Fe-biofortified beans, both separate from and within a targeted diet or meal plan.
The LC/MS analysis was carried out using Advion Expression® CMS ESI.
