ABSTRACT
An important question is what genes govern the differentiation of plant embryos into suspensor and embryo proper regions following fertilization and division of the zygote. We compared embryo proper and suspensor transcriptomes of four plants that vary in embryo morphology within the suspensor region. We determined that genes encoding enzymes in several metabolic pathways leading to the formation of hormones, such as gibberellic acid, and other metabolites are up-regulated in giant scarlet runner bean and common bean suspensors. Genes involved in transport and Golgi body organization are up-regulated within the suspensors of these plants as well, strengthening the view that giant specialized suspensors serve as a hormone factory and a conduit for transferring substances to the developing embryo proper. By contrast, genes controlling transcriptional regulation, development, and cell division are up-regulated primarily within the embryo proper. Transcriptomes from less specialized soybean and Arabidopsis suspensors demonstrated that fewer genes encoding metabolic enzymes and hormones are up-regulated. Genes active in the embryo proper, however, are functionally similar to those active in scarlet runner bean and common bean embryo proper regions. We uncovered a set of suspensor- and embryo proper-specific transcription factors (TFs) that are shared by all embryos irrespective of morphology, suggesting that they are involved in early differentiation processes common to all plants. Chromatin immunoprecipitation sequencing (ChIP-Seq) experiments with scarlet runner bean and soybean WOX9, an up-regulated suspensor TF, gained entry into a regulatory network important for suspensor development irrespective of morphology.
Subject(s)
Plant Development/genetics , Plant Proteins/genetics , Seeds/genetics , Transcriptome/genetics , Arabidopsis/genetics , Arabidopsis/growth & development , Cell Division/genetics , Gene Expression Regulation, Plant/genetics , Gibberellins/metabolism , Seeds/metabolism , Glycine max/genetics , Glycine max/growth & developmentABSTRACT
Ticlopidine is an antithrombotic prodrug of the thienotetrahydropyridine family. For platelet inhibition it has to undergo oxidative ring-opening by cytochrome P450 enzymes. The resulting thiol reacts with a cysteine residue of the purinergic P2Y12 receptor on thrombocytes resulting in covalent receptor blockade. Ticlopidine in its intact, not-metabolized form was previously shown to inhibit ecto-nucleoside triphosphate diphosphohydrolase-1 (NTPDase1, also known as cluster of differentiation (CD) 39). CD39 catalyzes the extracellular hydrolysis of ATP via ADP to AMP, which is further hydrolyzed by ecto-5'-nucleotidase (CD73) to adenosine. CD39 inhibition has been proposed as a novel strategy to increase the extracellular concentration of antiproliferative ATP, while decreasing immunosuppressive and cancer-promoting adenosine levels. In the present study, we performed an extensive structure-activity relationship (SAR) analysis of ticlopidine derivatives and analogs as CD39 inhibitors followed by an in-depth characterization of selected compounds. Altogether 74 compounds were synthesized, 41 of which are new, not previously described in literature. Benzotetrahydropyridines, in which the metabolically labile thiophene is replaced by a benzene ring, were discovered as a new class of allosteric CD39 inhibitors.
Subject(s)
Adenosine Triphosphate , Ticlopidine , Adenosine , Blood Platelets , Structure-Activity Relationship , 5'-Nucleotidase/metabolismABSTRACT
Ectonucleotidases, a well-known superfamily of plasma membrane located metalloenzymes plays a central role in mediating the process of purinergic cell signaling. Major functions performed by these enzymes include the hydrolysis of extracellular nucleosides and nucleotides which are considered as important cell-signaling molecules. Any (patho)-physiologically induced disruption in this purinergic cell signaling leads to several disorders, hence these enzymes are important drug targets for therapeutic purposes. Among the major challenges faced in the design of inhibitors of ectonucleotidases, an important one is the lack of selective inhibitors. Access to highly selective inhibitors via a facile synthetic route will not only be beneficial therapeutically, but will also lead to an increase in our understanding of intricate interplay between members of ectonucleotidase enzymes in relation to their selective activation and/or inhibition in different cells and tissues. Herein we describe synthesis of highly selective inhibitors of human intestinal alkaline phosphatase (h-IAP) and human tissue non-specific alkaline phosphatase (h-TNAP), containing chromone sulfonamide and sulfonylhydrazone scaffolds. Compound 1c exhibited highest (and most selective) h-IAP inhibition activity (h-IAP IC50 = 0.51 ± 0.20 µM; h-TNAP = 36.5%) and compound 3k showed highest activity and selective inhibition against h-TNAP (h-TNAP IC50 = 1.41 ± 0.10 µM; h-IAP = 43.1%). These compounds were also evaluated against another member of ectonucleotidase family, that is rat and human ecto-5'-nucleotidase (r-e5'NT and h-e5'NT). Some of the compounds exhibited excellent inhibitory activity against ecto-5'-nucleotidase. Compound 2 g exhibited highest inhibition against h-e5'NT (IC50 = 0.18 ± 0.02 µM). To rationalize the interactions with the binding site, molecular docking studies were carried out.
Subject(s)
5'-Nucleotidase , Alkaline Phosphatase , Rats , Humans , Animals , Molecular Docking Simulation , Enzyme Inhibitors/chemistry , Sulfonamides/pharmacology , Sulfonamides/chemistry , Chromones/pharmacologyABSTRACT
The LEAFY COTYLEDON1 (LEC1) transcription factor is a central regulator of seed development, because it controls diverse biological programs during seed development, such as embryo morphogenesis, photosynthesis, and seed maturation. To understand how LEC1 regulates different gene sets during development, we explored the possibility that LEC1 acts in combination with other transcription factors. We identified and compared genes that are directly transcriptionally regulated by ABA-RESPONSIVE ELEMENT BINDING PROTEIN3 (AREB3), BASIC LEUCINE ZIPPER67 (bZIP67), and ABA INSENSITIVE3 (ABI3) with those regulated by LEC1. We showed that LEC1 operates with specific sets of transcription factors to regulate different gene sets and, therefore, distinct developmental processes. Thus, LEC1 controls diverse processes through its combinatorial interactions with other transcription factors. DNA binding sites for the transcription factors are closely clustered in genomic regions upstream of target genes, defining cis-regulatory modules that are enriched for DNA sequence motifs that resemble sequences known to be bound by these transcription factors. Moreover, cis-regulatory modules for genes regulated by distinct transcription factor combinations are enriched for different sets of DNA motifs. Expression assays with embryo cells indicate that the enriched DNA motifs are functional cis elements that regulate transcription. Together, the results suggest that combinatorial interactions between LEC1 and other transcription factors are mediated by cis-regulatory modules containing clustered cis elements and by physical interactions that are documented to occur between the transcription factors.
Subject(s)
CCAAT-Enhancer-Binding Proteins/metabolism , Glycine max/growth & development , Glycine max/metabolism , Seeds/growth & development , Transcription Factors/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Basic-Leucine Zipper Transcription Factors/genetics , Binding Sites , CCAAT-Enhancer-Binding Proteins/genetics , DNA-Binding Proteins , Gene Expression Regulation, Plant , Nucleotide Motifs , Plant Development/genetics , Plant Development/physiology , Plant Proteins/genetics , Plant Proteins/metabolism , RNA, Messenger , Glycine max/embryology , Glycine max/genetics , Transcription Factors/geneticsABSTRACT
OBJECTIVE: Nucleotides are danger signals that activate inflammatory responses via binding P2 receptors. The nucleoside triphosphate diphosphohydrolase-8 (NTPDase8) is an ectonucleotidase that hydrolyses P2 receptor ligands. We investigated the role of NTPDase8 in intestinal inflammation. DESIGN: We generated NTPDase8-deficient (Entpd8-/-) mice to define the role of NTPDase8 in the dextran sodium sulfate (DSS) colitis model. To assess inflammation, colons were collected and analysed by histopathology, reverse transcriptase-quantitative real-time PCR (RT-qPCR) and immunohistochemistry. P2 receptor expression was analysed by RT-qPCR on primary intestinal epithelium and NTPDase8 activity by histochemistry. The role of intestinal P2Y6 receptors was assessed by bone marrow transplantation experiments and with a P2Y6 receptor antagonist. RESULTS: NTPDase8 is the dominant enzyme responsible for the hydrolysis of nucleotides in the lumen of the colon. Compared with wild-type (WT) control mice, the colon of Entpd8-/- mice treated with DSS displayed significantly more histological damage, immune cell infiltration, apoptosis and increased expression of several proinflammatory cytokines. P2Y6 was the dominant P2Y receptor expressed at the mRNA level by the colonic epithelia. Irradiated P2ry6-/- mice transplanted with WT bone marrow were fully protected from DSS-induced intestinal inflammation. In agreement, the daily intrarectal injection of a P2Y6 antagonist protected mice from DSS-induced intestinal inflammation in a dose-dependent manner. Finally, human intestinal epithelial cells express NTPDase8 and P2Y6 similarly as in mice. CONCLUSION: NTPDase8 protects the intestine from inflammation most probably by limiting the activation of P2Y6 receptors in colonic epithelial cells. This may provide a novel therapeutic strategy for the treatment of inflammatory bowel disease.
Subject(s)
Adenosine Triphosphatases/metabolism , Colitis/metabolism , Isothiocyanates/pharmacology , Receptors, Purinergic P2/genetics , Receptors, Purinergic P2/metabolism , Thiourea/analogs & derivatives , Adenosine Triphosphatases/genetics , Animals , Apoptosis , Bone Marrow Transplantation , Colon/metabolism , Cytokines/metabolism , Dextran Sulfate/pharmacology , Disease Models, Animal , Epithelial Cells/metabolism , Humans , Immunohistochemistry , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Mice, Inbred C57BL , Mice, Knockout , RNA, Messenger/metabolism , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Thiourea/pharmacologyABSTRACT
P2Y6 receptor (P2Y6R) antagonists represent potential drugs for treating cancer, pain, neurodegeneration, asthma, diabetes, colitis and other disorders. However, there are few chemical classes of known competitive antagonists. We recently explored the structure activity relationship (SAR) of 2H-chromene derivatives as P2Y6R antagonists of moderate affinity. New analogues in this series modified at five positions were synthesized and shown to antagonize Ca2+ transients induced by the native agonist UDP in human (h) P2Y6R-expressing (but not turkey P2Y1R-, hP2Y2R- or hP2Y4R-expressing) astrocytoma cells. Alternatives to the reported 2-(trifluoromethyl)- and 3-nitro- substitutions of this scaffold were not identified. However, 6fluoro 11 and 6chloro 12 analogues displayed enhanced potency compared to other halogens, although still in the 1 - 2 µM range. Similar halogen substitution at 5, 7 or 8 positions reduced affinity. 5- or 8Triethylsilylethynyl extension maintained hP2Y6R affinity, with IC50 0.46 µM for 26 (MRS4853). The 6,8difluoro analogue 27 (IC50 2.99 µM) lacked off-target activities among 45 sites examined, unlike earlier analogues that bound to biogenic amine receptors. 11 displayed only one weak off-target activity (σ2). Mouse P2Y6R IC50s of 5, 25, 26 and 27 were 4.94, 17.6, 6.15 and 17.8 µM, respectively, but most other analogues had reduced affinity (>20 µM) compared to the hP2Y6R. These analogues are suitable for evaluation in in vivo inflammation and cancer models, which will be performed in the future studies.
Subject(s)
Receptors, Purinergic P2 , Animals , Benzopyrans , Halogens , Humans , Mice , Receptors, Purinergic P2/metabolism , Structure-Activity Relationship , Uridine DiphosphateABSTRACT
The h-NTPDases is an essential family of ectonucleotidases that consists of eight isozymes with various physiological functions. The undesired activity of the h-NTPDases leads to pathological conditions such as cancer, diabetes, inflammation, and thrombosis. In the present study, a series of thienopyrimidines was synthesized employing a sequential SNAr and Suzuki coupling to synthesize diverse aryl substituted thienopyrimidine glycinate derivatives. The synthesized compounds constituted electron donating, electron-deficient, heteroaryl, and fluorinated substituents. The thienopyrimidines were screened against h-NTPDases to determine the effect on the activity of the h-NTPDases-1, -2, -3, and -8. The compound 3j selectively blocked the isozyme h-NTPDases1, while the compounds 3e, 3m, and 4a were selective inhibitors of h-NTPDases2. The activity of the isozyme h-NTPDases3 was selectively reduced by inhibitor 3k whereas, the compound 3d was found as the most active inhibitor against isozyme h-NTPDase8. The molecular docking study interpreted the interactions of the potent inhibitors of the respective isozymes with important amino acid residues i.e., Asp54, Ser57, His59, Ser58, His59, Asp213, and Phe360 of h-NTPDases1 protein; residues Arg 392, Ala393, Ala347, Tye350 and Arg245 of h-NTPDases2; amino acids Arg67, Ser65, Ala323, Gly222, and Tyr375 of h-NTPDases3 whereas in case of h-NTPDases8, the residues Val436, Gln74, Gly179, and Val71 were involved in interaction with the inhibitors docked into the active sites of these isozymes.
Subject(s)
Isoenzymes , Pyrimidines , Molecular Docking Simulation , Structure-Activity Relationship , Pyrimidines/pharmacology , Molecular StructureABSTRACT
Sepsis is life-threatening organ dysfunction caused by a dysregulated inflammatory and immune response to infection. Sepsis involves the combination of exaggerated inflammation and immune suppression. During systemic infection and sepsis, the liver works as a lymphoid organ with key functions in regulating the immune response. Extracellular nucleotides are considered damage-associated molecular patterns and are involved in the control of inflammation. Their levels are finely tuned by the membrane-associated ectonucleoside triphosphate diphosphohydrolase (E-NTPDase) enzyme family. Although previous studies have addressed the role of NTPDase1 (CD39), the role of the other extracellular NTPDases, NTPDase2, -3, and -8, in sepsis is unclear. In the present studies we identified NTPDase8 as a top downregulated gene in the liver of mice submitted to cecal ligation-induced sepsis. Immunohistochemical analysis confirmed the decrease of NTPDase8 expression at the protein level. In vitro mechanistic studies using HepG2 hepatoma cells demonstrated that IL-6 but not TNF, IL-1ß, bacteria, or lipopolysaccharide are able to suppress NTPDase8 gene expression. NTPDase8, as well as NTPDase2 and NTPDase3 mRNA was downregulated, whereas NTPDase1 (CD39) mRNA was upregulated in polymorphonuclear leukocytes from both inflamed and septic patients compared to healthy controls. Although the host's inflammatory response of polymicrobial septic NTPDase8 deficient mice was no different from that of wild-type mice, IL-6 levels in NTPDase8 deficient mice were higher than IL-6 levels in wild-type mice with pneumonia. Altogether, the present data indicate that extracellular NTPDases are differentially regulated during sepsis.
Subject(s)
Adenosine Triphosphatases/metabolism , Inflammation/metabolism , Leukocytes/metabolism , Sepsis/metabolism , Adenosine Triphosphatases/genetics , Animals , Female , Humans , Inflammation/genetics , Liver/metabolism , Male , Mice , Mice, Knockout , Sepsis/geneticsABSTRACT
Members of the ectonucleoside triphosphate diphosphohydrolases (NTPDases) constitute the major family of enzymes responsible for the maintenance of extracellular levels of nucleotides and nucleosides by catalyzing the hydrolysis of nucleoside triphosphate (NTP) and nucleoside diphosphates (NDP) to nucleoside monophosphate (NMP). Although, NTPDase inhibitors can act as potential drug candidates for the treatment of various diseases, there is lack of potent as well as selective inhibitors of NTPDases. The current study describes the synthesis of a number of carboxamide derivatives that were tested on recombinant human (h) NTPDases. The most promising inhibitors were 2h (h-NTPDase1, IC50: 0.12 ± 0.03 µM), 2d (h-NTPDase2, IC50: 0.15 ± 0.01 µM) and 2a (h-NTPDase3, IC50: 0.30 ± 0.04 µM; h-NTPDase8, IC50: 0.16 ± 0.02 µM). Four compounds (2e, 2f, 2g and 2h) were associated with the selective inhibition of h-NTPDase1 while 2b was identified as a selective h-NTPDase3 inhibitor. Considering the importance of NTPDase3 in the regulation of insulin release, the NTPDase3 inhibitors were further investigated to elucidate their role in the insulin release. The obtained data suggested that compound 2a was actively participating in regulating the insulin release without producing any effect on NTPDase3 mRNA. Moreover, the most potent inhibitors were docked within the active site of respective enzyme and the observed interactions were in compliance with in vitro results. Hence, these compounds can be used as pharmacological tool to further investigate the role of NTPDase3 coupled to insulin release.
Subject(s)
Adenosine Triphosphatases/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Indoles/pharmacology , Molecular Docking Simulation , Phenylhydrazines/pharmacology , Adenosine Triphosphatases/metabolism , Dose-Response Relationship, Drug , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Humans , Indoles/chemical synthesis , Indoles/chemistry , Molecular Structure , Phenylhydrazines/chemical synthesis , Phenylhydrazines/chemistry , Structure-Activity RelationshipABSTRACT
Quinoline derivatives have interesting biological profile. In continuation for the comprehensive evaluations of substituted quinoline derivatives against human nucleoside triphosphate diphosphohydrolases (h-NTPDases) a series of substituted quinoline derivatives (2a-g, 3a-f, 4, 5a-c, 6) was synthesized. The inhibitory activities of the synthesized compounds were evaluated against four isoenzymes of human nucleoside triphosphate diphosphohydrolases (h-NTPDases). These quinoline derivatives had IC50 (µM) values in the range of 0.20-1.75, 0.77-2.20, 0.36-5.50 and 0.90-1.82 for NTPDase1, NTPDase2, NTPDase3 and NTPDase8, respectively. The derivative 3f was the most active compound against NTPDase1 (IC50, 0.20 ± 0.02 µM) that also possessed selectivity towards NTPDase1. Similarly, derivative 3b (IC50, 0.77 ± 0.06), 2h (IC50, 0.36 ± 0.01) and 2c (IC50, 0.90 ± 0.08) displayed excellent activity corresponding to NTPDase2, NTPDase3 and NTPdase8. The compound 5c emerged as a selective inhibitor of NTPDase8. The most active compounds were then investigated to determine their mode of inhibition and finally binding interactions of the active compounds were analyzed through molecular docking studies. The obtained results strongly support the quinoline scaffold's potential as potent and selective NTPDase inhibitor.
Subject(s)
Adenosine Triphosphatases/antagonists & inhibitors , Apyrase/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Quinolines/pharmacology , Adenosine Triphosphatases/metabolism , Apyrase/metabolism , Dose-Response Relationship, Drug , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Humans , Molecular Structure , Quinolines/chemical synthesis , Quinolines/chemistry , Structure-Activity RelationshipABSTRACT
Extracellular ATP mediates proinflammatory and antiproliferative effects via activation of P2 nucleotide receptors. In contrast, its metabolite, the nucleoside adenosine, is strongly immunosuppressive and enhances tumor proliferation and metastasis. The conversion of ATP to adenosine is catalyzed by ectonucleotidases, which are expressed on immune cells and typically upregulated on tumor cells. In the present study, we identified sulfopolysaccharides from brown and red sea algae to act as potent dual inhibitors of the main ATP-hydrolyzing ectoenzymes, ectonucleotide pyrophosphatase/phosphodiesterase-1 (NPP1) and ecto-nucleoside triphosphate diphosphohydrolase-1 (NTPDase1, CD39), showing nano- to picomolar potency and displaying a non-competitive mechanism of inhibition. We showed that one of the sulfopolysaccharides tested as a representative example reduced adenosine formation at the surface of the human glioblastoma cell line U87 in a concentration-dependent manner. These natural products represent the most potent inhibitors of extracellular ATP hydrolysis known to date and have potential as novel therapeutics for the immunotherapy of cancer.
Subject(s)
Adenosine Triphosphate/antagonists & inhibitors , Apyrase/antagonists & inhibitors , Polysaccharides/physiology , Pyrophosphatases/antagonists & inhibitors , Seaweed , Sulfuric Acid Esters/pharmacology , Adenosine Triphosphate/metabolism , Apyrase/metabolism , Cell Line, Tumor , Dose-Response Relationship, Drug , Humans , Hydrolysis/drug effects , Phosphoric Diester Hydrolases/metabolism , Polysaccharides/chemistry , Polysaccharides/isolation & purification , Pyrophosphatases/metabolism , Seaweed/chemistry , Seaweed/isolation & purification , Sulfuric Acid Esters/chemistry , Sulfuric Acid Esters/isolation & purificationABSTRACT
The precise mechanisms that control gene activity during seed development remain largely unknown. Previously, we showed that several genes essential for seed development, including those encoding storage proteins, fatty acid biosynthesis enzymes, and transcriptional regulators (e.g., ABI3, FUS3) are located within hypomethylated regions of the soybean genome. These hypomethylated regions are similar to the DNA methylation valleys (DMVs), or canyons, found in mammalian cells. Here, we address the question of the extent to which DMVs are present within seed genomes and what role they might play in seed development. We scanned soybean and Arabidopsis seed genomes from postfertilization through dormancy and germination for regions that contain <5% or <0.4% bulk methylation in CG, CHG, and CHH contexts over all developmental stages. We found that DMVs represent extensive portions of seed genomes, range in size from 5-76 kb, are scattered throughout all chromosomes, and are hypomethylated throughout the plant life cycle. Significantly, DMVs are enriched greatly in transcription factor (TF) genes and other developmental genes that play critical roles in seed formation. Many DMV genes are regulated with respect to seed stage, region, and tissue, and contain H3K4me3, H3K27me3, or bivalent marks that fluctuate during development. Our results indicate that DMVs are a unique regulatory feature of both plant and animal genomes, and that a large number of seed genes are regulated in the absence of methylation changes during development, probably by the action of specific TFs and epigenetic events at the chromatin level.
Subject(s)
Arabidopsis Proteins , Arabidopsis , DNA Methylation/physiology , DNA, Plant , Genome, Plant/physiology , Glycine max , Seeds , Transcription Factors , Arabidopsis/genetics , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , DNA, Plant/genetics , DNA, Plant/metabolism , Epigenesis, Genetic/physiology , Gene Expression Regulation, Plant/physiology , Seeds/genetics , Seeds/metabolism , Glycine max/genetics , Glycine max/metabolism , Transcription Factors/genetics , Transcription Factors/metabolismABSTRACT
The antithrombotic prodrugs ticlopidine and clopidogrel are thienotetrahydro-pyridine derivatives that are metabolized in the liver to produce thiols that irreversibly block adenosine diphosphate (ADP)-activated P2Y12 receptors on thrombocytes. In their native, nonmetabolized form, both drugs were reported to act as inhibitors of ectonucleoside triphosphate diphosphohydrolase-1 (NTPDase1, CD39). CD39 catalyzes the extracellular hydrolysis of nucleoside tri- and diphosphates, mainly adenosine 5'-triphosphate (ATP) and ADP, yielding adenosine monophosphate, which is further hydrolyzed by ecto-5'-nucleotidase (CD73) to produce adenosine. While ATP has proinflammatory effects, adenosine is a potent anti-inflammatory, immunosuppressive agent. Inhibitors of CD39 and CD73 have potential as novel checkpoint inhibitors for the immunotherapy of cancer and infection. In the present study, we investigated 2-substituted thienotetrahydropyridine derivatives, structurally related to ticlopidine, as CD39 inhibitors. Due to their substituent on the 2-position, they will not be metabolically transformed into reactive thiols and can, therefore, be expected to be devoid of P2Y12 receptor-antagonistic activity in vivo. Several of the investigated 2-substituted thienotetrahydropyridine derivatives showed concentration-dependent inhibition of CD39. The most potent derivative, 32, showed similar CD39-inhibitory potency to ticlopidine, both acting as allosteric inhibitors. Compound 32 showed an improved selectivity profile: While ticlopidine blocked several NTPDase isoenzymes, 32 was characterized as a novel dual inhibitor of CD39 and CD73.
Subject(s)
5'-Nucleotidase/antagonists & inhibitors , Apyrase/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Thienopyridines/pharmacology , Allosteric Regulation/drug effects , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , GPI-Linked Proteins/antagonists & inhibitors , Humans , Structure-Activity Relationship , Thienopyridines/chemical synthesis , Thienopyridines/chemistry , Ticlopidine/pharmacologyABSTRACT
Adenosine pathway, including its generating enzyme (CD73) and its receptors represents a key target for cancer immunotherapy. Here we aimed to search for novel compounds able to co-target the CD73 and the A2A adenosine receptor (A2A AR) as dual-blockers of adenosine generation and activity. The design project was to combine in the same molecule the thiazolo[5,4-d]pyrimidine core, an essential pharmacophoric feature to block the A2A AR, with a benzenesulfonamide group which is a characteristic group of CD73 inhibitors. Most of the reported compounds resulted in inverse agonists of the human (h) A2A AR endowed with high affinity, selectivity and potency. However they were weak inhibitors of CD73 enzyme. Nevertheless, this study can be considered as a starting point to develop more active compounds.
Subject(s)
5'-Nucleotidase/antagonists & inhibitors , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Adenosine A2 Receptor Agonists , Adenosine A2 Receptor Antagonists , GPI-Linked Proteins/antagonists & inhibitors , Molecular Structure , Receptor, Adenosine A2AABSTRACT
Alkaline phosphatases (ALPs) are membrane bound metalloenzymes, distributed all over the body. Recent studies have revealed that by targeting ALPs can lead towards the treatment of many deadliest diseases including cardiac, cancerous and brain diseases. Thioureas and their derivatives are of considerable significance and are privileged scaffolds in medicinal chemistry. They show a wide range of pharmacological activities such as antibacterial, antiparasitic, anti-inflammatory and antioxidants etc. On the other hand, salicylic acid and its derivatives are known for its broad spectrum of activities. The work presented comprises of synthesis of N-acyl-N'-aryl substituted bisthioureas of pimelic acid (1-7) and 3,5-dimethyl pyrazole (11), 1-aroyl-3-aryl thiourea (12) and 1,3,4-oxadiazole (13) derivatives of 4-methyl salicylic acid. Structures of all the synthesized compounds were characterized by FT-IR and 1H NMR spectroscopic analysis. Synthesized compounds were evaluated for their alkaline phosphatases inhibition potential and exhibited high potency as well as selectivity towards h-TNAP and h-IAP. Compound 7 and 12 which were the bisthiourea derivative of pimmelic acid and thiourea derivative of 4-methyl salicylic acid, respectively, showed excellent selectivity against h-TNAP and h-IAP, respectively.
Subject(s)
Alkaline Phosphatase/antagonists & inhibitors , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Intestines/enzymology , Pimelic Acids/chemistry , Salicylates/chemistry , Thiourea/pharmacology , Enzyme Inhibitors/chemical synthesis , Hydrogen Bonding , Molecular Docking Simulation , Structure-Activity Relationship , Thiourea/chemistryABSTRACT
Alkaline phosphatases (APs) are a class of homodimeric enzymes which physiologically possess the dephosphorylation ability. APs catalyzes the hydrolysis of monoesters into phosphoric acid which in turn catalyze a transphosphorylation reaction. Thiazoles are nitrogen and sulfur containing aromatic heterocycles considered as effective APs inhibitors. In this context, the current research paper presents the successful synthesis, spectroscopic characterization and in vitro alkaline phosphatase inhibitory potential of new thiazole derivatives. The structure activity relationship and molecular docking studies were performed to find out the binding modes of the screened compounds with the target site of tissue non-specific alkaline phosphatase (h-TNAP) as well as intestinal alkaline phosphatase (h-IAP). Compound 5e was found to be potent inhibitor of h-TNAP with IC50 value of 0.17 ± 0.01 µM. Additionally, compounds 5a and 5i were found to be highly selective toward h-TNAP with IC50 values of 0.25 ± 0.01 µM and 0.21 ± 0.02 µM, respectively. In case of h-IAP compound 5f was the most potent inhibitor with IC50 value of 1.33 ± 0.10 µM. The most active compounds were resort to molecular docking studies on h-TNAP and h-IAP to explore the possible binding interactions of enzyme-ligand complexes. Molecular dynamic simulations were carried out to investigate the overall stability of protein in apo and holo state.
Subject(s)
Alkaline Phosphatase/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Intestines/embryology , Thiazoles/pharmacology , Alkaline Phosphatase/metabolism , Animals , COS Cells , Chlorocebus aethiops , Dose-Response Relationship, Drug , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Humans , Models, Molecular , Molecular Structure , Structure-Activity Relationship , Thiazoles/chemical synthesis , Thiazoles/chemistryABSTRACT
Ectonucleotidases are a broad family of ectoenzymes that play a crucial role in purinergic cell signaling. Ecto-nucleotide pyrophosphatases/phosphodiesterases (NPPs) belong to this group and are important drug targets. In particular, NPP1 and NPP3 are known to be druggable targets for treatment of impaired calcification disorders (including pathological aortic calcification) and cancer, respectively. In this study, we investigated a series of sulfonate and sulfamate derivatives of benzofuran and benzothiophene as potent and selective inhibitors of NPP1 and NPP3. Compounds 1c, 1g, 1n, and 1s are the most active NPP1 inhibitors (IC50 values in the range 0.12-0.95 µM). Moreover, compounds 1e, 1f, 1j, and 1l are the most potent inhibitors of NPP3 (IC50 ranges from 0.12 to 0.95 µM). Compound 1d, 1f and 1t are highly selective inhibitors of NPP1 over NPP3, whereas compounds 1m and 1s are found to be highly selective towards NPP3 over NPP1. Structure-activity relationship (SAR) study has been discussed in detailed. With the aid of molecular docking studies, a common binding mode of these compounds and suramin (the standard inhibitor) was revealed, where the sulfonate group acts as a cation-binding moiety that comes in close contact with the zinc ion of the active site. Moreover, cytotoxic evaluation against MCF-7 and HT-29 cancer cell lines revealed that compound 1r is the most cytotoxic towards MCF-7 cell line with IC50 value of 0.19 µM. Compound 1r is more potent and selective against cancer cells than normal cells (WI-38) as compared to doxorubicin.
Subject(s)
Antineoplastic Agents/pharmacology , Benzofurans/pharmacology , Enzyme Inhibitors/pharmacology , Sulfonic Acids/pharmacology , Thiophenes/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Benzofurans/chemical synthesis , Benzofurans/chemistry , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Humans , Molecular Docking Simulation , Molecular Structure , Phosphoric Diester Hydrolases/metabolism , Pyrophosphatases/antagonists & inhibitors , Pyrophosphatases/metabolism , Structure-Activity Relationship , Sulfonic Acids/chemical synthesis , Sulfonic Acids/chemistry , Thiophenes/chemical synthesis , Thiophenes/chemistry , Tumor Cells, CulturedABSTRACT
Medicinal importance of the sulfonylhydrazones is well-evident owing to their binding ability with zinc containing metalloenzymes. In the present study, we have synthesized different series of sulfonylhydrazones by using facile synthetic methods in good to excellent yield. All the successfully prepared sulfonylhydrazones were screened for ectonucleotidase (ALP & e5'NT) inhibitory activity. Among the chromen-2-one scaffold based sulfonylhydrazones, the compounds 7 was found to be most potent inhibitor for h-TNAP (human tissue non-specific alkaline phosphatase) and h-IAP (human intestinal alkaline phosphatase) with IC50 values of 1.02 ± 0.13 and 0.32 ± 0.0 3 µM respectively, compared with levamisole (IC50 = 25.2 ± 1.90 µM for h-TNAP) and l-phenylalanine (IC50 = 100 ± 3.00 µM for h-IAP) as standards. Further, the chromen-2-one based molecule 5a showed excellent activity against h-ecto 5'-NT (human ecto-5'-nucleotidase) with IC50 value of 0.29 ± 0.004 µM compared to standard, sulfamic acid (IC50 = 42.1 ± 7.8 µM). However, among the series of phenyl ring based sulfonylhydrazones, compound 9d was found to be most potent against h-TNAP and h-IAP with IC50 values of 0.85 ± 0.08 and 0.52 ± 0.03 µM, respectively. Moreover, in silico studies were also carried to demonstrate their putative binding with the target enzymes. The potent compounds 5a, 7, and 9d against different ectonucleotidases (h-ecto 5'-NT, h-TNAP, h-IAP) could potentially serve as lead for the development of new therapeutic agents.
Subject(s)
5'-Nucleotidase/antagonists & inhibitors , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Hydrazones/chemistry , Hydrazones/pharmacology , 5'-Nucleotidase/metabolism , Alkaline Phosphatase/antagonists & inhibitors , Alkaline Phosphatase/metabolism , Benzopyrans/chemical synthesis , Benzopyrans/chemistry , Benzopyrans/pharmacology , Drug Design , Enzyme Inhibitors/chemical synthesis , GPI-Linked Proteins/antagonists & inhibitors , GPI-Linked Proteins/metabolism , Humans , Hydrazones/chemical synthesis , Molecular Docking Simulation , Structure-Activity Relationship , Sulfinic Acids/chemical synthesis , Sulfinic Acids/chemistry , Sulfinic Acids/pharmacologyABSTRACT
A series of six compounds (1a-f) possessing pyridine-pyrazole-benzenethiourea or pyridine-pyrazole-benzenesulfonamide scaffold were synthesized. The target compounds were screened to evaluate their inhibitory effect on human nucleotide pyrophosphatase/phosphodiesterase 1 and -3 (ENPP1 and ENPP3) isoenzymes. Compounds 1c-e were the most potent inhibitors of ENPP1 with sub-micromolar IC50 values (0.69, 0.18, and 0.40 µM, respectively. Moreover, compound 1b was the most potent inhibitor of ENPP3 (IC50 = 0.21 µM). They were much more potent than the reference standard inhibitor, suramin (IC50 values against ENPP1 and -3 were 7.77 and 0.89 µM, respectively). Furthermore, all the six compounds were investigated for cytotoxic effect against cancerous cell lines (HeLa, MCF-7, and 1321N1) and normal cell line (BHK-21). Compound 1e was active against all the three cancer cell lines, however, showed preferential cytotoxicity against MCF-7 (IC50 = 16.05 µM), which is comparable to the potency of cisplatin. All the tested compounds exhibited low or negligible cytotoxic effect against the normal cells. They have the merit of superior selectivity towards cancer cells than normal cells compared to cisplatin. The relative selectivity and potency of the inhibitors was justified by molecular docking studies. All the docked structures showed considerable binding interactions with amino acids residues of active sites of ENPP isoenzymes.
Subject(s)
Antineoplastic Agents/pharmacology , Enzyme Inhibitors/pharmacology , Pyrazoles/pharmacology , Sulfonamides/pharmacology , Thiourea/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Humans , Models, Molecular , Molecular Structure , Phosphoric Diester Hydrolases/metabolism , Pyrazoles/chemical synthesis , Pyrazoles/chemistry , Pyrophosphatases/antagonists & inhibitors , Pyrophosphatases/metabolism , Structure-Activity Relationship , Sulfonamides/chemical synthesis , Sulfonamides/chemistry , Thiourea/chemical synthesis , Thiourea/chemistryABSTRACT
LEAFY COTYLEDON1 (LEC1), an atypical subunit of the nuclear transcription factor Y (NF-Y) CCAAT-binding transcription factor, is a central regulator that controls many aspects of seed development including the maturation phase during which seeds accumulate storage macromolecules and embryos acquire the ability to withstand desiccation. To define the gene networks and developmental processes controlled by LEC1, genes regulated directly by and downstream of LEC1 were identified. We compared the mRNA profiles of wild-type and lec1-null mutant seeds at several stages of development to define genes that are down-regulated or up-regulated by the lec1 mutation. We used ChIP and differential gene-expression analyses in Arabidopsis seedlings overexpressing LEC1 and in developing Arabidopsis and soybean seeds to identify globally the target genes that are transcriptionally regulated by LEC1 in planta Collectively, our results show that LEC1 controls distinct gene sets at different developmental stages, including those that mediate the temporal transition between photosynthesis and chloroplast biogenesis early in seed development and seed maturation late in development. Analyses of enriched DNA sequence motifs that may act as cis-regulatory elements in the promoters of LEC1 target genes suggest that LEC1 may interact with other transcription factors to regulate distinct gene sets at different stages of seed development. Moreover, our results demonstrate strong conservation in the developmental processes and gene networks regulated by LEC1 in two dicotyledonous plants that diverged â¼92 Mya.