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Biomedicine & Pharmacotherapy =... Jul 2021This study was designed to determine the effectiveness of 5-(3-Hydroxybenzylidene)-2, 4, 6(1H, 3H, 5H)-pyrimidinetrione (SR-5), 5-(4-Hydroxybenzylidene)-2, 4, 6(1H, 3H,...
This study was designed to determine the effectiveness of 5-(3-Hydroxybenzylidene)-2, 4, 6(1H, 3H, 5H)-pyrimidinetrione (SR-5), 5-(4-Hydroxybenzylidene)-2, 4, 6(1H, 3H, 5H)-pyrimidinetrione (SR-8), 5-(3-Chlorobenzylidene)-2, 4, 6(1H, 3H, 5H)-pyrimidinetrione (SR-9) and 5-(4-Chlorobenzylidene)-2, 4, 6(1H, 3H, 5H)-pyrimidinetrione (SR-10) against hypertension. In deoxycorticosterone acetate-salt rats, SR-5, SR-8, SR-9, and SR-10 reduced blood pressure and normalized renal functions. In isolated rat aortic rings, SR-5, SR-8, SR-9, and SR-10 relaxed phenylephrine (PE) and K-induced contractions. The vasodilator effect was endothelium-independent. Test compounds caused a rightward shift of Ca and PE concentration-response curves with a reduction of maximum response. SR-5, SR-8, SR-9, and SR-10 inhibited PE peak contractions in a Ca free medium. In guinea-pig atria, SR5, SR-8, SR-9, and SR-10 caused a mild-to-moderate inhibition of force and rate of contractions. In the aorta and heart tissues, the test compounds enhanced glutathione-s-transferase, reduced glutathione and catalase levels, improved cellular architecture, and decreased lipid peroxidation and expression of inflammatory markers: cyclooxygenase 2, tumor necrosis factor alpha, phosphorylated c-Jun N-terminal kinase, and phosphorylated-nuclear factor kappa B, evidenced in the immunohistochemistry, enzyme-linked immunosorbent assay, western blot molecular investigations and a decreased mRNA expression of calcium channel in RT-PCR analysis. SR-5, SR-8, SR-9, and SR-10 increased the urinary output in rats and inhibited the human platelet aggregation. This study revealed that SR-5, SR-8, SR-9, and SR-10 possess BP lowering, reno-protective, vasodilatory (mediated via Ca antagonist, antioxidant and anti-inflammatory pathways), partial cardio-suppressant, diuretic, and antiplatelet effects, demonstrating their therapeutic potential in hypertension management.
Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Antihypertensive Agents; Antioxidants; Aorta; Calcium; Desoxycorticosterone; Female; Guinea Pigs; Humans; Hypertension; Kidney Function Tests; Male; Mice; Muscle Contraction; Muscle, Smooth, Vascular; Myocardial Contraction; Phenylephrine; Platelet Aggregation; Pyrimidines; Rats; Rats, Sprague-Dawley; Signal Transduction; Vasodilator Agents
PubMed: 33848773
DOI: 10.1016/j.biopha.2021.111567 -
The Journal of Biological Chemistry Jan 2023Oxidation of DNA bases generates mutagenic and cytotoxic lesions that are implicated in cancer and other diseases. Oxidative base lesions, including...
Oxidation of DNA bases generates mutagenic and cytotoxic lesions that are implicated in cancer and other diseases. Oxidative base lesions, including 7,8-dihydro-8-oxoguanine, are typically removed through base excision repair. In addition, oxidized deoxynucleotides such as 8-oxo-dGTP are depleted by sanitizing enzymes to preclude DNA incorporation. While pathways that counter threats posed by 7,8-dihydro-8-oxoguanine are well characterized, mechanisms protecting against the major adenine oxidation product, 7,8-dihydro-8-oxoadenine (oxoA), are poorly understood. Human DNA polymerases incorporate dGTP or dCTP opposite oxoA, producing mispairs that can cause A→C or A→G mutations. oxoA also perturbs the activity of enzymes acting on DNA and causes interstrand crosslinks. To inform mechanisms for oxoA repair, we characterized oxoA excision by human thymine DNA glycosylase (TDG), an enzyme known to remove modified pyrimidines, including deaminated and oxidized forms of cytosine and 5-methylcystosine. Strikingly, TDG excises oxoA from G⋅oxoA, A⋅oxoA, or C⋅oxoA pairs much more rapidly than it acts on the established pyrimidine substrates, whereas it exhibits comparable activity for T⋅oxoA and pyrimidine substrates. The oxoA activity depends strongly on base pairing and is 370-fold higher for G⋅oxoA versus T⋅oxoA pairs. The intrinsically disordered regions of TDG contribute minimally to oxoA excision, whereas two conserved residues (N140 and N191) are catalytically essential. Escherichia coli mismatch-specific uracil DNA-glycosylase lacks significant oxoA activity, exhibiting excision rates 4 to 5 orders of magnitude below that of its ortholog, TDG. Our results reveal oxoA as an unexpectedly efficient purine substrate for TDG and underscore the large evolutionary divergence of TDG and mismatch-specific uracil DNA-glycosylase.
Topics: Humans; Thymine DNA Glycosylase; DNA Repair; Adenine; DNA; Escherichia coli; Uracil; Thymine; Substrate Specificity
PubMed: 36460098
DOI: 10.1016/j.jbc.2022.102756 -
Ecotoxicology and Environmental Safety Dec 2022Thiram is a dithiocarbamate pesticide extensively used as a fungicide to preserve crops and seeds. Long-term exposure to thiram causes potential harm to the health of...
Thiram is a dithiocarbamate pesticide extensively used as a fungicide to preserve crops and seeds. Long-term exposure to thiram causes potential harm to the health of human beings and animals. So far, most of the researches on thiram focused on erythrocyte toxicity, immune system, kidney damage, and tibial dyschondroplasia; however, there is less data on cardiac toxicity. In this study, we examined cardiac histopathology, inflammatory factors, oxidative stress indicators, and apoptosis markers in the heart of broilers that were exposed to thiram. According to our findings, the continuous exposure to thiram caused pathological changes and abnormal function of myocardial tissues with increased level of inducible nitric oxide synthase (iNOS), inflammatory factors (IL-6, IL-8, TNF-α and NF-κB), and decreased level of anti-inflammatory factor (IL-10). In addition, thiram significantly upregulated the protein expression of cleaved-caspase 3, cleaved-PARP, and caused cardiomyocyte apoptosis. Meanwhile, the expression of heat shock proteins (HSP60, HSP70, HSP90) markedly decreased in the thiram-treated groups. An excessive accumulation of peroxidation products (MDA, HO), a decrease in T-AOC, and antioxidant activity enzymes (T-SOD, GST and GPX) were also noticed, all of which led to oxidative stress and activation of Nrf2 signal pathway by up-regulating key target genes (HO-1 and SODs). Thiram-induced metabolites were further identified via non-targeted metabonomic analysis. Correlation analysis revealed eighteen differentially expressed metabolites, closely related to cardiac injury. Importantly, thiram primarily affected the taurine and hypotaurine metabolism, pyrimidine metabolism as well as glycerol metabolism. Collectively, our study suggests that thiram could cause cardiotoxicity by interfering with taurine and hypotaurine metabolism, pyrimidine metabolism, and glycerolipid metabolism, which further induce oxidative stress via triggering Nrf2 signal pathway. This study may provide new evidence for the molecular mechanism of cardiotoxicity caused by thiram and resonate the alarm for animals and workers who have been exposed to thiram for a long time.
Topics: Animals; Humans; Thiram; NF-E2-Related Factor 2; Chickens; Cardiotoxicity; Hydrogen Peroxide; Oxidative Stress; Apoptosis; Taurine; Pyrimidines
PubMed: 36288636
DOI: 10.1016/j.ecoenv.2022.114225 -
Scientific Reports Jun 2020Uridine phosphorylase (UP) is a key enzyme of pyrimidine salvage pathways that enables the recycling of endogenous or exogenous-supplied pyrimidines and plays an...
Uridine phosphorylase (UP) is a key enzyme of pyrimidine salvage pathways that enables the recycling of endogenous or exogenous-supplied pyrimidines and plays an important intracellular metabolic role. Here, we biochemically and structurally characterized two evolutionarily divergent uridine phosphorylases, PcUP1 and PcUP2 from the oomycete pathogen Phytophthora capsici. Our analysis of other oomycete genomes revealed that both uridine phosphorylases are present in Phytophthora and Pythium genomes, but only UP2 is seen in Saprolegnia spp. which are basal members of the oomycetes. Moreover, uridine phosphorylases are not found in obligate oomycete pathogens such as Hyaloperonospora arabidopsidis and Albugo spp. PcUP1 and PcUP2 are upregulated 300 and 500 fold respectively, within 90 min after infection of pepper leaves. The crystal structures of PcUP1 in ligand-free and in complex with uracil/ribose-1-phosphate, 2'-deoxyuridine/phosphate and thymidine/phosphate were analyzed. Crystal structure of this uridine phosphorylase showed strict conservation of key residues in the binding pocket. Structure analysis of PcUP1 with bound ligands, and site-directed mutagenesis of key residues provide additional support for the "push-pull" model of catalysis. Our study highlights the importance of pyrimidine salvage during the earliest stages of infection.
Topics: Binding Sites; Catalysis; Catalytic Domain; Crystallography, X-Ray; Deoxyuridine; Ligands; Phytophthora; Pyrimidines; Ribosemonophosphates; Thymidine; Uracil; Uridine; Uridine Phosphorylase
PubMed: 32493959
DOI: 10.1038/s41598-020-65935-9 -
Molecules (Basel, Switzerland) Nov 2022Ten new differently substituted 3-benzyl-5-aryl-3,5-dihydro-4-benzo[6,7]chromeno[2,3-]pyrimidin-4,6,11-triones were synthesized by a simple and cost-efficient procedure...
Ten new differently substituted 3-benzyl-5-aryl-3,5-dihydro-4-benzo[6,7]chromeno[2,3-]pyrimidin-4,6,11-triones were synthesized by a simple and cost-efficient procedure in a one-pot, three-component reaction from readily available ethyl 2-amino-4-aryl-5,10-dioxo-5,10-dihydro-4-benzo[]chromene-3-carboxylates, benzylamine and triethyl orthoformate under solvent- and catalyst-free conditions. All the new compounds were screened for their antiproliferative activity against two colorectal-cancer-cell lines. The results showed that the compounds 3-benzyl-5-phenyl-3,5-dihydro-4-benzo[6,7]chromeno[2,3-]pyrimidine-4,6,11-trione () and 3-benzyl-5-(3-hydroxyphenyl)-3,5-dihydro-4-benzo[6,7]chromeno[2,3-]pyrimidine-4,6,11-trione () exhibited the most potent balanced inhibitory activity against human LoVo and HCT-116 cancer cells.
Topics: Humans; Pyrimidines; HCT116 Cells; Benzopyrans; Colorectal Neoplasms
PubMed: 36431976
DOI: 10.3390/molecules27227878 -
Yakugaku Zasshi : Journal of the... 2021I here present the results of our studies on the synthesis and functional analysis of tautomeric dihydropyrimidines (DPs) and related compounds in two sections. In the... (Review)
Review
I here present the results of our studies on the synthesis and functional analysis of tautomeric dihydropyrimidines (DPs) and related compounds in two sections. In the first section, we describe our experimental and theoretical studies on the thermodynamics and properties of 2-substituted 1,4- and 1,6-dihydropyrimidine-5-carboxylates by H NMR measurements and density functional theory (DFT) calculations, respectively. The concentration ratios of tautomers a/b of DPs 1, 2, and 3 were determined under various conditions to determine the effects of temperature, solvent, and concentration on thermodynamics data. The obtained free energy differences (ΔG), enthalpy differences (ΔH), and entropy differences (ΔS) are discussed in terms of the molecular structures, dipole moments (DM), and electrostatic potential maps obtained by DFT calculations to clarify the nature of DPs 4-8. In the second section, an efficient synthetic method developed for 6-unsubstituted 3,4-dihydropyrimidin-2(1H)-thiones 9 and 2-ones 10 is described. The novelties of the synthesis protocol are as follows: 1) the use of Lewis acid-mediated reaction, 2) good to high yields, and 3) its broad scope of applicability to aldehydes and ureas. Hitherto unavailable 6-unsubstituted 2-amino DP 11 and 2-aryl DP 12 were obtained from 9 by a substitution reaction with the amine and the Liebeskind-Srogl reaction, respectively. The compounds 9, 10, and related 6-methyl derivatives 19-21 were assessed for their antiproliferative effect on the human promyelocytic leukemia cell line HL-60. 4,4-Dipropyl derivative 20 showed relatively strong activity with an IC value of 341 nM.
Topics: Cell Proliferation; Dose-Response Relationship, Drug; HL-60 Cells; Humans; Leukemia, Promyelocytic, Acute; Molecular Structure; Pyrimidines; Solvents; Static Electricity; Structure-Activity Relationship; Temperature; Thermodynamics
PubMed: 33518632
DOI: 10.1248/yakushi.20-00182 -
Orphanet Journal of Rare Diseases Apr 2023Inherited Metabolic Disorders (IMDs) are rare diseases where one impaired protein leads to a cascade of changes in the adjacent chemical conversions. IMDs often present...
BACKGROUND
Inherited Metabolic Disorders (IMDs) are rare diseases where one impaired protein leads to a cascade of changes in the adjacent chemical conversions. IMDs often present with non-specific symptoms, a lack of a clear genotype-phenotype correlation, and de novo mutations, complicating diagnosis. Furthermore, products of one metabolic conversion can be the substrate of another pathway obscuring biomarker identification and causing overlapping biomarkers for different disorders. Visualization of the connections between metabolic biomarkers and the enzymes involved might aid in the diagnostic process. The goal of this study was to provide a proof-of-concept framework for integrating knowledge of metabolic interactions with real-life patient data before scaling up this approach. This framework was tested on two groups of well-studied and related metabolic pathways (the urea cycle and pyrimidine de-novo synthesis). The lessons learned from our approach will help to scale up the framework and support the diagnosis of other less-understood IMDs.
METHODS
Our framework integrates literature and expert knowledge into machine-readable pathway models, including relevant urine biomarkers and their interactions. The clinical data of 16 previously diagnosed patients with various pyrimidine and urea cycle disorders were visualized on the top 3 relevant pathways. Two expert laboratory scientists evaluated the resulting visualizations to derive a diagnosis.
RESULTS
The proof-of-concept platform resulted in varying numbers of relevant biomarkers (five to 48), pathways, and pathway interactions for each patient. The two experts reached the same conclusions for all samples with our proposed framework as with the current metabolic diagnostic pipeline. For nine patient samples, the diagnosis was made without knowledge about clinical symptoms or sex. For the remaining seven cases, four interpretations pointed in the direction of a subset of disorders, while three cases were found to be undiagnosable with the available data. Diagnosing these patients would require additional testing besides biochemical analysis.
CONCLUSION
The presented framework shows how metabolic interaction knowledge can be integrated with clinical data in one visualization, which can be relevant for future analysis of difficult patient cases and untargeted metabolomics data. Several challenges were identified during the development of this framework, which should be resolved before this approach can be scaled up and implemented to support the diagnosis of other (less understood) IMDs. The framework could be extended with other OMICS data (e.g. genomics, transcriptomics), and phenotypic data, as well as linked to other knowledge captured as Linked Open Data.
Topics: Humans; Metabolic Diseases; Biomarkers; Genomics; Metabolomics; Pyrimidines
PubMed: 37101200
DOI: 10.1186/s13023-023-02683-9 -
Molecules (Basel, Switzerland) Jan 2022A series of eleven 4-substituted 5,6,7,8-tetrahydrobenzo[4,5]thieno[2,3-]pyrimidines were designed and synthesized and their biological activities were evaluated....
A series of eleven 4-substituted 5,6,7,8-tetrahydrobenzo[4,5]thieno[2,3-]pyrimidines were designed and synthesized and their biological activities were evaluated. Synthesis involved the Gewald reaction to synthesize ethyl 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate ring, and SAr reactions. Compound was 1.6- and ~7-fold more potent than the lead compound in cell proliferation and microtubule depolymerization assays, respectively. Compounds , and showed the most potent antiproliferative effects (IC values < 40 nM), while compounds , , , and had lower antiproliferative potencies (IC values of 53-125 nM). Additionally, compounds -, and - circumvented Pgp and III-tubulin mediated drug resistance, mechanisms that diminish the clinical efficacy of paclitaxel (PTX). In the NCI-60 cell line panel, compound exhibited an average GI of ~10 nM in the 40 most sensitive cell lines. Compound demonstrated statistically significant antitumor effects in a murine MDA-MB-435 xenograft model.
Topics: Cell Line, Tumor; Cell Proliferation; Chemistry Techniques, Synthetic; Drug Design; Drug Resistance, Neoplasm; Humans; Models, Molecular; Molecular Conformation; Molecular Structure; Protein Multimerization; Pyrimidines; Structure-Activity Relationship; Tubulin; Tubulin Modulators
PubMed: 35011550
DOI: 10.3390/molecules27010321 -
Journal of Medicinal Chemistry Feb 2022We herein document a large collection of 108 2-amino-4,6-disubstituted-pyrimidine derivatives as potent, structurally simple, and highly selective AAR ligands. The most...
We herein document a large collection of 108 2-amino-4,6-disubstituted-pyrimidine derivatives as potent, structurally simple, and highly selective AAR ligands. The most attractive ligands were confirmed as antagonists of the canonical cyclic adenosine monophosphate pathway, and some pharmacokinetic parameters were preliminarilly evaluated. The library, built through a reliable and efficient three-component reaction, comprehensively explored the chemical space allowing the identification of the most prominent features of the structure-activity and structure-selectivity relationships around this scaffold. These included the influence on the selectivity profile of the aromatic residues at positions R and R of the pyrimidine core but most importantly the prominent role to the unprecedented AAR selectivity profile exerted by the methyl group introduced at the exocyclic amino group. The structure-activity relationship trends on both A and AARs were conveniently interpreted with rigorous free energy perturbation simulations, which started from the receptor-driven docking model that guided the design of these series.
Topics: Adenosine A1 Receptor Antagonists; Binding Sites; Cell Line; Drug Design; Drug Stability; Humans; Kinetics; Molecular Docking Simulation; Pyrimidines; Receptor, Adenosine A1; Receptor, Adenosine A2A; Structure-Activity Relationship
PubMed: 35068155
DOI: 10.1021/acs.jmedchem.1c01636 -
ChemMedChem Nov 2021Inhibition of membrane-bound pyrophosphatase (mPPase) with small molecules offer a new approach in the fight against pathogenic protozoan parasites. mPPases are absent...
Inhibition of membrane-bound pyrophosphatase (mPPase) with small molecules offer a new approach in the fight against pathogenic protozoan parasites. mPPases are absent in humans, but essential for many protists as they couple pyrophosphate hydrolysis to the active transport of protons or sodium ions across acidocalcisomal membranes. So far, only few nonphosphorus inhibitors have been reported. Here, we explore the chemical space around previous hits using a combination of screening and synthetic medicinal chemistry, identifying compounds with low micromolar inhibitory activities in the Thermotoga maritima mPPase test system. We furthermore provide early structure-activity relationships around a new scaffold having a pyrazolo[1,5-a]pyrimidine core. The most promising pyrazolo[1,5-a]pyrimidine congener was further investigated and found to inhibit Plasmodium falciparum mPPase in membranes as well as the growth of P. falciparum in an ex vivo survival assay.
Topics: Dose-Response Relationship, Drug; Humans; Molecular Structure; Pyrazoles; Pyrimidines; Pyrophosphatases; Structure-Activity Relationship
PubMed: 34459148
DOI: 10.1002/cmdc.202100392