共查询到20条相似文献,搜索用时 8 毫秒
1.
Sonia Martínez González Ana Isabel Hernández Rosa María Álvarez Antonio Rodríguez Francisco Ramos-Lima James R. Bischoff María Isabel Albarrán Antonio Cebriá Elena Hernández-Encinas Jennifer García-Arocha David Cebrián Carmen Blanco-Aparicio Joaquín Pastor 《Bioorganic & medicinal chemistry letters》2017,27(21):4794-4799
A scaffold hopping strategy, including intellectual property availability assessment, was successfully applied for the discovery of novel PI3K inhibitors. Compounds were designed based on the chemical structure of the lead compound ETP-46321, a potent PI3K inhibitor, previously reported by our group. The new generated compounds showed good in vitro potency and selectivity, proved to inhibit potently the phosphorylation of AKTSer473 in cells and demonstrated to be orally bioavailable, thus becoming potential back-up candidates for ETP-46321. 相似文献
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Vilar M Murillo-Carretero M Mira H Magnusson K Besset V Ibáñez CF 《The EMBO journal》2006,25(6):1219-1230
A screening for intracellular interactors of the p75 neurotrophin receptor (p75NTR) identified brain-expressed X-linked 1 (Bex1), a small adaptor-like protein of unknown function. Bex1 levels oscillated during the cell cycle, and preventing the normal cycling and downregulation of Bex1 in PC12 cells sustained cell proliferation under conditions of growth arrest, and inhibited neuronal differentiation in response to nerve growth factor (NGF). Neuronal differentiation of precursors isolated from the brain subventricular zone was also reduced by ectopic Bex1. In PC12 cells, Bex1 overexpression inhibited the induction of NF-kappaB activity by NGF without affecting activation of Erk1/2 and AKT, while Bex1 knockdown accelerated neuronal differentiation and potentiated NF-kappaB activity in response to NGF. Bex1 competed with RIP2 for binding to the p75NTR intracellular domain, and elevating RIP2 levels restored the ability of cells overexpressing Bex1 to differentiate in response to NGF. Together, these data establish Bex1 as a novel link between neurotrophin signaling, the cell cycle, and neuronal differentiation, and suggest that Bex1 may function by coordinating internal cellular states with the ability of cells to respond to external signals. 相似文献
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Alternative splicing of the TrkB gene produces a full length tyrosine kinase receptor as well as two truncated isoforms that contain extracellular and transmembrane domains but lack the kinase domain and have unique C terminal tails. The function of the truncated TrkB isoforms is unclear and to gain insights into their function, we have isolated a protein from 15N neuroblastoma cells that specifically binds the TrkB.T1 isoform. Pulldown experiments using a GST fusion protein containing the TrkB.T1 intracellular domain identified a 61 kDa protein from radiolabeled 15N lysates. Coimmunoprecipitation experiments showed that the 61 kDa protein interacted with epitope-tagged TrkB.T1 overexpressed in 15N cells as well as with TrkB.T1 which was endogenously expressed. Peptide competition experiments revealed that the protein, designated TTIP (for Truncated TrkB Interacting Protein), showed specific binding to the TrkB.T1 tail. MALDI MS and MS/MS analysis has revealed that TTIP is a novel protein not yet listed in the current databases. 相似文献
4.
Amino acid changes at Ambler position R244 in class A TEM and SHV beta-lactamases confer resistance to ampicillin/clavulanate, a beta-lactam/beta-lactamase inhibitor combination used to treat serious infections. To gain a deeper understanding of this resistance phenotype, we investigated the activities of sulbactam and two novel penem beta-lactamase inhibitors with sp2 hybridized C3 carboxylates and bicyclic R1 side chains against a library of SHV beta-lactamase variants at the 244 position. Compared to SHV-1 expressed in Escherichia coli, all 19 R244 variants exhibited increased susceptibility to ampicillin/sulbactam, an important difference compared to ampicillin/clavulanate. Kinetic analyses of SHV-1 and three SHV R244 (-S, -Q, and -L) variants revealed the Ki for sulbactam was significantly elevated for the R244 variants, but the partition ratios, kcat/kinact, were markedly reduced (13 000 --> 相似文献
5.
Wilson LJ Wang B Yang SM Scannevin RH Burke SL Karnachi P Rhodes KJ Murray WV 《Bioorganic & medicinal chemistry letters》2011,21(21):6485-6490
The discovery of potent N-hydroxyl caprolactam matrix metalloproteinase (MMP) inhibitors (6) based on the natural product Cobactin-T (2) is described. The synthetic method, which utilizes the ring closing metathesis reaction, is compatible to provide complementary (R) and (S) enantiomers. These compounds tested against MMP-2 and 9, show that the R stereochemistry (i.e., 16), which is opposite for that found in the natural product Cobactin-T is >1000-fold more active with IC(50) values of 0.2-0.6nM against both enzymes. The variation in the incorporation of the sulfonamide enzyme recognition element (Ar(2)XAr(1)SO(2)N(R(1)), 6), along with alterations in the RCM/double bond chemistry (R(2)) provided a series of sub nanomolar MMP inhibitors. For example, compounds 16 and 34 were found to be the most potent with IC(50) values against MMP-2 and MMP-9 found to be between 0.2 and 0.6nM with 34 being the most potent compound discovered (MMP-2 IC(50)=0.39nM and MMP-9 IC(50)=0.22nM). Compounds 16 and 34 showed acceptable drug-like properties in vivo with compound 34 showing oral bioavailability. 相似文献
6.
Signaling mechanisms of the myelin inhibitors of axon regeneration 总被引:16,自引:0,他引:16
One of the major obstacles to successful axon regeneration in the adult CNS is the presence of inhibitory molecules that are associated with myelin. Recent studies have identified several major myelin-associated inhibitors along with the relevant signaling molecules. Such advances have not only enhanced our understanding of the signaling mechanisms that are involved in the inhibition of axon regeneration in the adult CNS but also allowed us to assess the therapeutic potential of blocking these inhibitory influences to promote axon regeneration. 相似文献
7.
Bevacqua RJ Pereyra-Bonnet F Olivera R Hiriart MI Sipowicz P Fernandez-Martín R Radrizzani M Salamone DF 《Theriogenology》2012,78(1):57-68
The objective was to evaluate the effects of cell cycle inhibitors (6-dimethylaminopurine [DMAP], and dehydroleukodine [DhL]) on transgene expression efficiency and on mosaic expression patterns of IVF bovine zygotes cytoplasmically injected with oolema vesicles coincubated with transgene. The DNA damage induced by the transgene or cell cycle inhibitors was measured by detection of phosphorylated histone H2AX foci presence (marker of DNA double-stranded breaks). Cloning of egfp blastomeres was included to determine continuity of expression after additional rounds of cellular division. The pCX-EGFP [enhanced green fluorescent protein gene (EGFP) under the chimeric cytomegalovirus IE-chicken-β-actin enhancer promoter control] gene plasmid (50 ng/μL) was injected alone (linear or circular exogenous DNA, leDNA and ceDNA, respectively) or associated with ooplasmic vesicles (leDNA-v or ceDNA-v). The effects of 2 mm DMAP or 1 μm DhL for 6 h (from 15 to 21 h post IVF) was evaluated for groups injected with vesicles. The DMAP increased (P < 0.05) egfp homogenous expression relative to transgene alone (21%, 18%, and 11% for leDNA-v + DMAP, leDNA-v, and leDNA, respectively) and also increased (P < 0.05) the phosphorylated histone H2AX foci area. Expression of egfp was higher (P < 0.05) for linear than for circular pCX-EGFP, and egfp blastocyst rates were higher (P < 0.05) for groups injected with linear transgene coincubated with vesicles than for linear transgene alone (95%, 77%, 84%, and 52% for leDNA-v + DMAP, leDNA-v + DhL, leDNA-v, and leDNA, respectively). Moreover, DMAP tended to improve egfp blastocysts rates for both circular and linear transgenes. Based on fluorescent in situ hybridization (FISH) analysis, there was evidence of integration in egfp embryos. Finally, clones derived from leDNA-v + DMAP had the highest egfp expression rates (96%, 65%, and 65% for leDNA-v + DMAP, leDNA-v, and leDNA, respectively). Transgenesis by cytoplasmic injection of leDNA-v + DMAP is a promising alternative for transgenic animal production. 相似文献
8.
A large fraction of the marine bacterioplankton community is unable to form colonies on agar surfaces, which so far no experimental evidence can explain. Here we describe a previously undescribed growth behavior of three non-colony-forming oligotrophic bacterioplankton, including a SAR11 cluster representative, the world's most abundant organism. We found that these bacteria exhibit a behavior that promotes growth and dispersal instead of colony formation. Although these bacteria do not form colonies on agar, it was possible to monitor growth on the surface of seawater agar slides containing a fluorescent stain, 4',6'-diamidino-2-phenylindole (DAPI). Agar slides were prepared by pouring a solution containing 0.7% agar and 0.5 micro g of DAPI per ml in seawater onto glass slides. Prompt dispersal of newly divided cells explained the inability to form colonies since immobilized cells (cells immersed in agar) formed microcolonies. The behavior observed suggests a life strategy intended to optimize access of individual cells to substrates. Thus, the inability to form colonies or biofilms appears to be part of a K-selected population strategy in which oligotrophic bacteria explore dissolved organic matter in seawater as single cells. 相似文献
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Yuka Miyake Yukihiro Itoh Atsushi Hatanaka Yoshinori Suzuma Miki Suzuki Hidehiko Kodama Yoshinobu Arai Takayoshi Suzuki 《Bioorganic & medicinal chemistry》2019,27(6):1119-1129
Histone lysine demethylases (KDMs) have drawn much attention as targets of therapeutic agents. KDM5 proteins, which are Fe(II)/α-ketoglutarate-dependent demethylases, are associated with oncogenesis and drug resistance in cancer cells, and KDM5-selective inhibitors are expected to be anticancer drugs. However, few cell-active KDM5 inhibitors have been reported and there is an obvious need to discover more. In this study, we pursued the identification of highly potent and cell-active KDM5-selective inhibitors. Based on the reported KDM5 inhibitors, we designed several compounds by strategically merging two fragments for competitive inhibition with α-ketoglutarate and for KDM5-selective inhibition. Among them, compounds 10 and 13, which have a 3-cyano pyrazolo[1,5-a]pyrimidin-7-one scaffold, exhibited strong KDM5-inhibitory activity and significant KDM5 selectivity. In cellular assays using human lung cancer cell line A549, 10 and 13 increased the levels of trimethylated lysine 4 on histone H3, which is a specific substrate of KDM5s, and induced growth inhibition of A549 cells. These results should provide a basis for the development of cell-active KDM5 inhibitors to highlight the validity of our inhibitor-based fragment merging strategy. 相似文献
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Angela Rizzo Carmen Maresca Carmen D'Angelo Manuela Porru Serena Di Vito Erica Salvati Andrea Sacconi Francesco Berardinelli Antonella Sgura Sergey Kuznetsov Swapnil Potdar Antti Hassinen Antonella Stoppacciaro Pasquale Zizza Annamaria Biroccio 《Aging cell》2023,22(11):e13944
Drug repositioning strategy represents a valid tool to accelerate the pharmacological development through the identification of new applications for already existing compounds. In this view, we aimed at discovering molecules able to trigger telomere-localized DNA damage and tumor cell death. By applying an automated high-content spinning-disk microscopy, we performed a screening aimed at identifying, on a library of 527 drugs, molecules able to negatively affect the expression of TRF2, a key protein in telomere maintenance. FK866, resulting from the screening as the best candidate hit, was then validated at biochemical and molecular levels and the mechanism underlying its activity in telomere deprotection was elucidated both in vitro and in vivo. The results of this study allow us to discover a novel role of FK866 in promoting, through the production of reactive oxygen species, telomere loss and deprotection, two events leading to an accumulation of DNA damage and tumor cell death. The ability of FK866 to induce telomere damage and apoptosis was also demonstrated in advanced preclinical models evidencing the antitumoral activity of FK866 in triple-negative breast cancer—a particularly aggressive breast cancer subtype still orphan of targeted therapies and characterized by high expression levels of both NAMPT and TRF2. Overall, our findings pave the way to the development of novel anticancer strategies to counteract triple-negative breast cancer, based on the use of telomere deprotecting agents, including NAMPT inhibitors, that would rapidly progress from bench to bedside. 相似文献
13.
《Biochimica et Biophysica Acta (BBA)/General Subjects》2020,1864(6):129546
Multidrug efflux is a major contributor to antibiotic resistance in Gram-negative bacterial pathogens. Inhibition of multidrug efflux pumps is a promising approach for reviving the efficacy of existing antibiotics. Previously, inhibitors targeting both the efflux transporter AcrB and the membrane fusion protein AcrA in the Escherichia coli AcrAB-TolC efflux pump were identified. Here we use existing physicochemical property guidelines to generate a filtered library of compounds for computational docking. We then experimentally test the top candidate coumpounds using in vitro binding assays and in vivo potentiation assays in bacterial strains with controllable permeability barriers. We thus identify a new class of inhibitors of E. coli AcrAB-TolC. Six molecules with a shared scaffold were found to potentiate the antimicrobial activity of erythromycin and novobiocin in hyperporinated E. coli cells. Importantly, these six molecules were also active in wild-type strains of both Acinetobacter baumannii and Klebsiella pneumoniae, potentiating the activity of erythromycin and novobiocin up to 8-fold. 相似文献
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NRAGE, a novel MAGE protein, interacts with the p75 neurotrophin receptor and facilitates nerve growth factor-dependent apoptosis 总被引:18,自引:0,他引:18
Salehi AH Roux PP Kubu CJ Zeindler C Bhakar A Tannis LL Verdi JM Barker PA 《Neuron》2000,27(2):279-288
The mechanisms employed by the p75 neurotrophin receptor (p75NTR) to mediate neurotrophin-dependent apoptosis are poorly defined. Two-hybrid analyses were used to identify proteins involved in p75NTR apoptotic signaling, and a p75NTR binding partner termed NRAGE (for neurotrophin receptor-interacting MAGE homolog) was identified. NRAGE binds p75NTR in vitro and in vivo, and NRAGE associates with the plasma membrane when NGF is bound to p75NTR. NRAGE blocks the physical association of p75NTR with TrkA, and, conversely, TrkA overexpression eliminates NRAGE-mediated NGF-dependent death, indicating that interactions of NRAGE or TrkA with p75NTR are functionally and physically exclusive. NRAGE overexpression facilitates cell cycle arrest and permits NGF-dependent apoptosis within sympathetic neuron precursors cells. Our results show that NRAGE contributes to p75NTR-dependent cell death and suggest novel functions for MAGE family proteins. 相似文献
16.
Human dihydroorotate dehydrogenase (hDHODH) is a flavin-dependent enzyme essential to pyrimidine de novo biosynthesis, which serves as an attractive therapeutic target for the treatment of autoimmune disorders. A novel series of hDHODH inhibitors was developed based on a lead which was obtained by a medicinal chemistry exploration. Most compounds showed moderate to significant potency against hDHODH, compounds 5d, 5e, and 6a effectively inhibited the activities of hDHODH with IC50 values from 0.9 to 2.8 μM. Further studies showed that compound 5e also effectively suppressed proliferation of the activated PBMCs (IC50 = 20.35 μM). Surprisingly, compound 5e also showed anti-pulmonary fibrotic activity similar to that of pirfenidone in vitro assay. Therefore, compound 5e might have potential to be developed as a novel hDHODH inhibitors for autoimmune diseases therapy. 相似文献
17.
Takashi Inuzuka Shuzo Sato Hiroko Baba Tadashi Miyatake 《Neurochemical research》1986,11(10):1407-1417
Neutral protease is shown to be present in cell-free human cerebrospinal fluid. Incubation of heated human myelin with CSF at 25°C resulted in a marked reduction of myelin basic protein (MBP) with time. Degradation products appeared at apparent mol wt 14 KDa and 12 KDa on polyacrylamide gel electrophoresis. Optimal pH of the protease was 7.0. This protease was activated by calcium ion. Degradation of MBP was inhibited by FOY305 (camostat mesilate), Trasylol®, and Leupeptin, but not a specific calcium-activated neutral protease inhibitor, E-64-a. FOY305, which is a synthesized specific serine protease inhibitor, was the strongest inhibitor of all. The role of this protease in CSF has not been elucidated. In may be related to the physiological turnover of MBP, and may affect myelin maintenance in pathological conditions such as demyelination. 相似文献
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Homeostasis is a key feature of cellular lifespan. Maintenance of cellular homeostasis influences the rate of aging and is determined by several factors, including efficient proteolysis of damaged proteins. Protein degradation is predominantly catalyzed by the proteasome. Specifically, the proteasome is responsible for cell clearance of abnormal, denatured or in general damaged proteins as well as for the regulated degradation of short-lived proteins. As proteasome has an impaired function during aging, emphasis has been given recently in identifying ways of its activation. A number of studies have shown that the proteasome can be activated by genetic manipulations as well as by factors that affect its conformation and stability. Importantly the developed proteasome activated cell lines exhibit an extended lifespan. This review article discusses in details the various factors that are involved in proteasome biosynthesis and assembly and how they contribute to its activation. Finally as few natural compounds have been identified having proteasome activation properties, we discuss the advantages of this novel antiaging strategy. 相似文献