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1.
Int J Mol Sci ; 22(15)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34360534

RESUMO

Inorganic phosphate (Pi) is an essential nutrient for living organisms and is maintained in equilibrium in the range of 0.8-1.4 mM Pi. Pi is a source of organic constituents for DNA, RNA, and phospholipids and is essential for ATP formation mainly through energy metabolism or cellular signalling modulators. In mitochondria isolated from the brain, liver, and heart, Pi has been shown to induce mitochondrial reactive oxygen species (ROS) release. Therefore, the purpose of this review article was to gather relevant experimental records of the production of Pi-induced reactive species, mainly ROS, to examine their essential roles in physiological processes, such as the development of bone and cartilage and the development of diseases, such as cardiovascular disease, diabetes, muscle atrophy, and male reproductive system impairment. Interestingly, in the presence of different antioxidants or inhibitors of cytoplasmic and mitochondrial Pi transporters, Pi-induced ROS production can be reversed and may be a possible pharmacological target.


Assuntos
Doenças Cardiovasculares/patologia , Diabetes Mellitus/patologia , Mitocôndrias/patologia , Atrofia Muscular/patologia , Fosfatos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/metabolismo , Diabetes Mellitus/etiologia , Diabetes Mellitus/metabolismo , Metabolismo Energético , Humanos , Mitocôndrias/efeitos dos fármacos , Atrofia Muscular/etiologia , Atrofia Muscular/metabolismo
2.
Molecules ; 26(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203117

RESUMO

Three phosphate glass compositions, VF1, VF2, and VF3, containing macro and micronutrients with different [K2O/(CaO+MgO)] ratio, were formulated to be used as controlled release fertilizers for tomato crop, depending on their chemical durability in water and their propriety with respect to the standards of controlled-release fertilizers. This study investigated the influence of [K2O/(CaO+MgO)] ratio variation on glass properties. For this, the elaborated glasses have undergone a chemical characterization using inductively coupled plasma atomic emission spectroscopy, a thermal characterization using differential thermal analysis, a physicochemical characterization based on density and molar volume measurements, and a structural characterization using Raman spectroscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction. In addition, the chemical durability was determined by measuring the percentage of weight loss and the pH. Results revealed that the glass structure and composition have the mean role in controlling the release of nutrients in water. By increasing [K2O/(CaO+MgO)] ratio, the dissolution rates of the glasses increased due to the shrinking in the rate of crosslinking between phosphate chains, accompanied with a diminution in transition and crystallization temperatures, and an increase in the molar volume. An agronomic valorization of VF1 and VF2 glass fertilizers, which showed dissolution profiles adequate to the criteria of controlled-release fertilizers, was carried out to evaluate their efficiency on tomato crops. These glass fertilizers improved soil mineral content and tomato performances in comparison to the control and NPK treatments with the distinction of VF2. The results highlight the effectiveness of these smart fertilizers toward their potential large-scale application to improve crop production and quality for high nutritional value foods.


Assuntos
Produção Agrícola , Produtos Agrícolas/crescimento & desenvolvimento , Fertilizantes , Frutas/crescimento & desenvolvimento , Vidro/química , Lycopersicon esculentum/crescimento & desenvolvimento , Fosfatos , Solo , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Fosfatos/química , Fosfatos/farmacologia
3.
Eur J Med Chem ; 220: 113544, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34052678

RESUMO

10-Hydroxyevodiamine is a multitargeting antitumor lead compound with excellent in vitro activity. However, its in vivo antitumor potency is rather limited, which has hampered its further clinical development. To overcome this obstacle, a series of novel water-soluble derivatives of 10-hydroxyevodiamine were designed and synthesized. Most of them exhibited good to excellent antitumor activities against several cancer cell lines. In particular, phosphate derivative 9 was orally active and showed improved in vivo antitumor efficacy in HCT116 xenograft models. Further antitumor mechanism studies indicated that compound 9 acted by triple Top1/Top2/tubulin inhibition and induced apoptosis with G2/M cell cycle arrest. Taken together, this study extended the structure-activity relationship of evodiamine and identified phosphate derivative 9 as a promising antitumor lead compound.


Assuntos
Antineoplásicos/farmacologia , Descoberta de Drogas , Fosfatos/farmacologia , Quinazolinas/farmacologia , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , DNA Topoisomerases Tipo I/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células HCT116 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Fosfatos/administração & dosagem , Fosfatos/química , Quinazolinas/administração & dosagem , Quinazolinas/química , Solubilidade , Relação Estrutura-Atividade , Água/química
4.
J Med Chem ; 64(11): 7596-7616, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34019405

RESUMO

Cyclic dinucleotides (CDNs) are second messengers that bind to the stimulator of interferon genes (STING) and trigger the expression of type I interferons and proinflammatory cytokines. Here we evaluate the activity of 3',3'-c-di(2'F,2'dAMP) and its phosphorothioate analogues against five STING allelic forms in reporter-cell-based assays and rationalize our findings with X-ray crystallography and quantum mechanics/molecular mechanics calculations. We show that the presence of fluorine in the 2' position of 3',3'-c-di(2'F,2'dAMP) improves its activity not only against the wild type (WT) but also against REF and Q STING. Additionally, we describe the synthesis of the acyloxymethyl and isopropyloxycarbonyl phosphoester prodrugs of CDNs. Masking the negative charges of the CDNs results in an up to a 1000-fold improvement of the activities of the prodrugs relative to those of their parent CDNs. Finally, the uptake and intracellular cleavage of pivaloyloxymethyl prodrugs to the parent CDN is rapid, reaching a peak intracellular concentration within 2 h.


Assuntos
Ésteres/química , Proteínas de Membrana/agonistas , Fosfatos/química , Pró-Fármacos/síntese química , Cristalografia por Raios X , Teoria da Densidade Funcional , Ésteres/farmacologia , Ésteres/uso terapêutico , Células HEK293 , Humanos , Interferon gama/metabolismo , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Espectroscopia de Ressonância Magnética , Proteínas de Membrana/metabolismo , Fosfatos/metabolismo , Fosfatos/farmacologia , Fosfatos/uso terapêutico , Pró-Fármacos/química , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
5.
Plant Cell ; 33(4): 1361-1380, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-33793856

RESUMO

Aluminum (Al) toxicity and inorganic phosphate (Pi) limitation are widespread chronic abiotic and mutually enhancing stresses that profoundly affect crop yield. Both stresses strongly inhibit root growth, resulting from a progressive exhaustion of the stem cell niche. Here, we report on a casein kinase 2 (CK2) inhibitor identified by its capability to maintain a functional root stem cell niche in Arabidopsis thaliana under Al toxic conditions. CK2 operates through phosphorylation of the cell cycle checkpoint activator SUPPRESSOR OF GAMMA RADIATION1 (SOG1), priming its activity under DNA-damaging conditions. In addition to yielding Al tolerance, CK2 and SOG1 inactivation prevents meristem exhaustion under Pi starvation, revealing the existence of a low Pi-induced cell cycle checkpoint that depends on the DNA damage activator ATAXIA-TELANGIECTASIA MUTATED (ATM). Overall, our data reveal an important physiological role for the plant DNA damage response pathway under agriculturally limiting growth conditions, opening new avenues to cope with Pi limitation.


Assuntos
Alumínio/toxicidade , Arabidopsis/citologia , Arabidopsis/efeitos dos fármacos , Caseína Quinase II/metabolismo , Fosfatos/metabolismo , Alumínio/farmacocinética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Caseína Quinase II/genética , Peptídeos e Proteínas de Sinalização Intercelular , Fosfatos/farmacologia , Fosforilação , Células Vegetais/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
ACS Appl Mater Interfaces ; 13(10): 11631-11645, 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33685118

RESUMO

Copper-containing antimicrobials are highly valuable in the field of medical disinfectants owing to their well-known high antimicrobial efficacy. Artificially synthesized nanozymes which can increase the level of reactive oxygen species (ROS) in the bacterial system have become research hotspots. Herein, we describe the design and fabrication of degradable Cu-doped phosphate-based glass (Cu-PBG) nanozyme, which can achieve excellent antibacterial effects against Gram-positive and Gram-negative bacteria. The antibacterial mechanism is based on the generation of ROS storm and the release of copper. It behaves like a peroxidase in wounds which are acidic and exerts lethal oxidative stress on bacteria via catalyzing the decomposition of H2O2 into hydroxyl radicals (•OH). Quite different from any other reported nanozymes, the Cu-PBG is intrinsically degradable due to its phosphate glass nature. It gradually degrades and releases copper ions in a physiological environment, which further enhances the inhibition efficiency. Satisfactory antibacterial effects are verified both in vitro and in vivo. Being biodegradable, the prepared Cu-PBG exhibits excellent in vivo biocompatibility and does not cause any adverse effects caused by its long-time residence time in living organisms. Collectively, these results indicate that the Cu-PBG nanozyme could be used as an efficient copper-containing antimicrobial with great potential for clinical translation.


Assuntos
Antibacterianos/química , Cobre/química , Desinfetantes/química , Vidro/química , Nanoestruturas/química , Fosfatos/química , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Catálise , Cobre/farmacologia , Desinfetantes/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Infecções por Escherichia coli/prevenção & controle , Humanos , Peróxido de Hidrogênio/metabolismo , Fosfatos/farmacologia , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia
7.
Angew Chem Int Ed Engl ; 60(23): 12796-12801, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33783926

RESUMO

Changing an oxygen atom of the phosphoester bond in phosphopeptides by a sulfur atom enables instantly targeting Golgi apparatus (GA) and selectively killing cancer cells by enzymatic self-assembly. Specifically, conjugating cysteamine S-phosphate to the C-terminal of a self-assembling peptide generates a thiophosphopeptide. Being a substrate of alkaline phosphatase (ALP), the thiophosphopeptide undergoes rapid ALP-catalyzed dephosphorylation to form a thiopeptide that self-assembles. The thiophosphopeptide enters cells via caveolin-mediated endocytosis and macropinocytosis and instantly accumulates in GA because of dephosphorylation and formation of disulfide bonds in Golgi by themselves and with Golgi proteins. Moreover, the thiophosphopeptide potently and selectively inhibits cancer cells (HeLa) with the IC50 (about 3 µM), which is an order of magnitude more potent than that of the parent phosphopeptide.


Assuntos
Fosfatase Alcalina/metabolismo , Complexo de Golgi/efeitos dos fármacos , Peptídeos/farmacologia , Fosfatos/farmacologia , Complexo de Golgi/metabolismo , Células HeLa , Humanos , Estrutura Molecular , Peptídeos/química , Peptídeos/metabolismo , Fosfatos/química , Fosfatos/metabolismo
8.
Molecules ; 26(5)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33668802

RESUMO

The reactive adenosine derivative, adenosine 5'-O-[S-(4-hydroxy-2,3-dioxobutyl)]-thiophosphate (AMPS-HDB), contains a dicarbonyl group linked to the purine nucleotide at a position equivalent to the pyrophosphate region of NAD+. AMPS-HDB was used as a chemical label towards Candida boidinii formate dehydrogenase (CbFDH). AMPS-HDB reacts covalently with CbFDH, leading to complete inactivation of the enzyme activity. The inactivation kinetics of CbFDH fit the Kitz and Wilson model for time-dependent, irreversible inhibition (KD = 0.66 ± 0.15 mM, first order maximum rate constant k3 = 0.198 ± 0.06 min-1). NAD+ and NADH protects CbFDH from inactivation by AMPS-HDB, showing the specificity of the reaction. Molecular modelling studies revealed Arg174 as a candidate residue able to be modified by the dicarbonyl group of AMPS-HDB. Arg174 is a strictly conserved residue among FDHs and is located at the Rossmann fold, the common mononucleotide-binding motif of dehydrogenases. Arg174 was replaced by Asn, using site-directed mutagenesis. The mutant enzyme CbFDHArg174Asn was showed to be resistant to inactivation by AMPS-HDB, confirming that the guanidinium group of Arg174 is the target for AMPS-HDB. The CbFDHArg174Asn mutant enzyme exhibited substantial reduced affinity for NAD+ and lower thermostability. The results of the study underline the pivotal and multifunctional role of Arg174 in catalysis, coenzyme binding and structural stability of CbFDH.


Assuntos
Arginina/antagonistas & inibidores , Formiato Desidrogenases/antagonistas & inibidores , Fosfatos/farmacologia , Saccharomycetales/enzimologia , Arginina/genética , Arginina/metabolismo , Formiato Desidrogenases/genética , Formiato Desidrogenases/metabolismo , Modelos Moleculares , Estrutura Molecular , Mutagênese Sítio-Dirigida , Fosfatos/química
9.
Int J Food Microbiol ; 345: 109150, 2021 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-33735782

RESUMO

Glycerol monolaurate (GML) is a monoglycerol ester of the fatty lauric acids, which has a wide-spectrum antimicrobial capacity, but fails to inactivate Gram-negative bacteria, especial Salmonella. To enhance the population reduction rate of GML for Salmonella, this reagent was combined with three disinfectants: lactic acid (LA), cetylpyridinium chloride (CPC), and trisodium phosphate (TSP), which can present acid, neutral, and alkaline in solution, respectively. The results showed that the 1% GML and a complex disinfectant (0.5% GML-0.025% LA) could powerfully inactivate Salmonella. Their population reduction rates respectively were able to achieve 99.92% and 98.29% with the vortex treatment, indicating that the vortex treatment could improve GML to destruct the outer membrane of Salmonella. During the simulation test of the soaking and rinse processing of chicken, for a short time (0 h), the effect of 0.5% GML-0.025% LA compound was better and more suitable for instantaneous inactivation than others, while for a long time (4 h), 1% GML exhibited a better bactericidal effect, which indicated it to be more suitable for long-term bacteriostasis. The characterization of color and texture for chicken samples were determined using Colormeter Ci7600, TA.XT Plus and Hyper-spectral Imager, which demonstrated that all samples treated by these complex disinfectants were not significantly different from untreated group. In conclusion, GML is a potential and superior disinfectant for the chicken process.


Assuntos
Desinfetantes/farmacologia , Doenças Transmitidas por Alimentos/prevenção & controle , Lauratos/farmacologia , Monoglicerídeos/farmacologia , Salmonella/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Cetilpiridínio/farmacologia , Galinhas/microbiologia , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Ácido Láctico/farmacologia , Fosfatos/farmacologia
10.
Appl Environ Microbiol ; 87(9)2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33608293

RESUMO

The recently isolated thermophilic cyanobacterium Thermosynechococcus elongatus PKUAC-SCTE542 (here Thermosynechococcus E542) is a promising strain for fundamental and applied research. Here, we used several improved ploidy estimation approaches, which include quantitative PCR (qPCR), spectrofluorometry, and flow cytometry, to precisely determine the ploidy level in Thermosynechococcus E542 across different growth stages and nutritional and stress conditions. The distribution of genome copies per cell among the populations of Thermosynechococcus E542 was also analyzed. The strain tends to maintain 3 or 4 genome copies per cell in lag phase, early growth phase, or stationary phase under standard conditions. Increased ploidy (5.5 ± 0.3) was observed in exponential phase; hence, the ploidy level is growth phase regulated. Nearly no monoploid cells were detected in all growth phases, and prolonged stationary phase could not yield ploidy levels lower than 3 under standard conditions. During the late growth phase, a significantly higher ploidy level was observed in the presence of bicarbonate (7.6 ± 0.7) and high phosphate (6.9 ± 0.2) at the expense of reduced percentages of di- and triploid cells. Meanwhile, the reduction in phosphates decreased the average ploidy level by increasing the percentages of mono- and diploid cells. In contrast, temperature and antibiotic stresses reduced the percentages of mono-, di-, and triploid cells yet maintained average ploidy. The results indicate a possible causality between growth rate, stress, and genome copy number across the conditions tested, but the exact mechanism is yet to be elucidated. Furthermore, the spectrofluorometric approach presented here is a quick and straightforward ploidy estimation method with reasonable accuracy.IMPORTANCE The present study revealed that the genome copy number (ploidy) status in the thermophilic cyanobacterium Thermosynechococcus E542 is regulated by growth phase and various environmental parameters to give us a window into understanding the role of polyploidy. An increased ploidy level is found to be associated with higher metabolic activity and increased vigor by acting as backup genetic information to compensate for damage to the other chromosomal copies. Several improved ploidy estimation approaches that may upgrade the ploidy estimation procedure for cyanobacteria in the future are presented in this work. Furthermore, the new spectrofluorometric method presented here is a rapid and straightforward method of ploidy estimation with reasonable accuracy compared to other laborious methods.


Assuntos
Variações do Número de Cópias de DNA , Genoma Bacteriano , Bicarbonatos/farmacologia , Temperatura Alta , Fosfatos/farmacologia , Poliploidia , Thermosynechococcus/efeitos dos fármacos , Thermosynechococcus/genética , Thermosynechococcus/crescimento & desenvolvimento
11.
Clin Sci (Lond) ; 135(3): 515-534, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33479769

RESUMO

In chronic kidney disease (CKD), hyperphosphatemia is a key factor promoting medial vascular calcification, a common complication associated with cardiovascular events and high mortality. Vascular calcification involves osteo-/chondrogenic transdifferentiation of vascular smooth muscle cells (VSMCs), but the complex signaling events inducing pro-calcific pathways are incompletely understood. The present study investigated the role of acid sphingomyelinase (ASM)/ceramide as regulator of VSMC calcification. In vitro, both, bacterial sphingomyelinase and phosphate increased ceramide levels in VSMCs. Bacterial sphingomyelinase as well as ceramide supplementation stimulated osteo-/chondrogenic transdifferentiation during control and high phosphate conditions and augmented phosphate-induced calcification of VSMCs. Silencing of serum- and glucocorticoid-inducible kinase 1 (SGK1) blunted the pro-calcific effects of bacterial sphingomyelinase or ceramide. Asm deficiency blunted vascular calcification in a cholecalciferol-overload mouse model and ex vivo isolated-perfused arteries. In addition, Asm deficiency suppressed phosphate-induced osteo-/chondrogenic signaling and calcification of cultured VSMCs. Treatment with the functional ASM inhibitors amitriptyline or fendiline strongly blunted pro-calcific signaling pathways in vitro and in vivo. In conclusion, ASM/ceramide is a critical upstream regulator of vascular calcification, at least partly, through SGK1-dependent signaling. Thus, ASM inhibition by repurposing functional ASM inhibitors to reduce the progression of vascular calcification during CKD warrants further study.


Assuntos
Transdiferenciação Celular , Proteínas Imediatamente Precoces/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Esfingomielina Fosfodiesterase/farmacologia , Calcificação Vascular/patologia , Amitriptilina/farmacologia , Animais , Células Cultivadas , Ceramidas/metabolismo , Condrogênese/efeitos dos fármacos , Fendilina/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Fosfatos/farmacologia
12.
Int J Mol Med ; 47(3)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33448317

RESUMO

Coronavirus disease 2019 (COVID­19), caused by severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2), was identified in December, 2019 in Wuhan, China. Since then, it has continued to spread rapidly in numerous countries, while the search for effective therapeutic options persists. Coronaviruses, including SARS­CoV­2, are known to suppress and evade the antiviral responses of the host organism mediated by interferon (IFN), a family of cytokines that plays an important role in antiviral defenses associated with innate immunity, and has been used therapeutically for chronic viral diseases and cancer. On the other hand, OncoTherad, a safe and effective immunotherapeutic agent in the treatment of non­muscle invasive bladder cancer (NMIBC), increases IFN signaling and has been shown to be a promising therapeutic approach for COVID­19 in a case report that described the rapid recovery of a 78­year­old patient with NMIBC with comorbidities. The present review discusses the possible synergistic action of OncoTherad with vitamin D, zinc and glutamine, nutrients that have been shown to facilitate immune responses mediated by IFN signaling, as well as the potential of this combination as a therapeutic option for COVID­19.


Assuntos
Antivirais/farmacologia , COVID-19/tratamento farmacológico , Glutamina/farmacologia , Glicoproteínas/farmacologia , Fatores Imunológicos/uso terapêutico , Interferons/metabolismo , Fosfatos/farmacologia , Vitamina D/farmacologia , Zinco/farmacologia , Idoso , Antivirais/uso terapêutico , COVID-19/metabolismo , Comorbidade , Sinergismo Farmacológico , Glicoproteínas/uso terapêutico , Humanos , Imunidade Inata/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Masculino , Fosfatos/uso terapêutico , Cálculos da Bexiga Urinária/tratamento farmacológico , Cálculos da Bexiga Urinária/epidemiologia
13.
ACS Infect Dis ; 7(2): 471-478, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33395259

RESUMO

A series of 7-deazaadenine ribonucleosides bearing alkyl, alkenyl, alkynyl, aryl, or hetaryl groups at position 7 as well as their 5'-O-triphosphates and two types of monophosphate prodrugs (phosphoramidates and S-acylthioethanol esters) were prepared and tested for antiviral activity against selected RNA viruses (Dengue, Zika, tick-borne encephalitis, West Nile, and SARS-CoV-2). The modified triphosphates inhibited the viral RNA-dependent RNA polymerases at micromolar concentrations through the incorporation of the modified nucleotide and stopping a further extension of the RNA chain. 7-Deazaadenosine nucleosides bearing ethynyl or small hetaryl groups at position 7 showed (sub)micromolar antiviral activities but significant cytotoxicity, whereas the nucleosides bearing bulkier heterocycles were still active but less toxic. Unexpectedly, the monophosphate prodrugs were similarly or less active than the corresponding nucleosides in the in vitro antiviral assays, although the bis(S-acylthioethanol) prodrug 14h was transported to the Huh7 cells and efficiently released the nucleoside monophosphate.


Assuntos
Antivirais/farmacologia , Pró-Fármacos/farmacologia , Purinas/farmacologia , Vírus de RNA/efeitos dos fármacos , Ribonucleosídeos/farmacologia , COVID-19/tratamento farmacológico , COVID-19/virologia , Linhagem Celular Tumoral , Vírus da Dengue/efeitos dos fármacos , Vírus da Encefalite Transmitidos por Carrapatos/efeitos dos fármacos , Humanos , Fosfatos/farmacologia , Nucleosídeos de Purina , RNA Polimerase Dependente de RNA/metabolismo , SARS-CoV-2/efeitos dos fármacos , Vírus do Nilo Ocidental/efeitos dos fármacos , Zika virus/efeitos dos fármacos
14.
Molecules ; 26(3)2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33503929

RESUMO

Betulin (BT) is a natural pentacyclic lupane-type triterpene exhibiting anticancer activity. Betulin derivatives bearing propynoyloxy and phosphate groups were prepared in an effort to improve the availability and efficacy of the drug. In this study, a comparative assessment of the in vitro anticancer activity of betulin and its four derivatives was carried out using two human breast cancer cell lines: SK-BR-3 and MCF-7. In both studied cell lines, 30-diethoxyphosphoryl-28-propynoylbetulin (compound 4) turned out to be the most powerful inhibitor of growth and inducer of cellular death. Detailed examination of that derivative pertained to the mechanisms underlying its anticancer action. Treatment with compound 4 decreased DNA synthesis and up-regulated p21WAF1/Cip1 mRNA and protein levels in both cell lines. On the other hand, that derivative caused a significant increase in cell death, as evidenced by increased lactate dehydrogenase (LDH) release and ethidium homodimer uptake. Shortly after the compound addition, an increased generation of reactive oxygen species and loss of mitochondrial membrane potential were detected. The activation of caspase-3 and fragmentation of genomic DNA suggested an apoptotic type of cell death. However, analysis of cellular morphology did not reveal any nuclear features typical of apoptosis. Despite necrosis-like morphology, dead cells exhibited activation of the cascade of caspases. These observations have led to the conclusion that compound 4 pushed cells to undergo a form of necrotic-like regulated cell demise.


Assuntos
Alcinos/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Morte Celular/efeitos dos fármacos , Necrose/tratamento farmacológico , Fosfatos/farmacologia , Triterpenos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Caspases/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , L-Lactato Desidrogenase/metabolismo , Células MCF-7 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima/efeitos dos fármacos
15.
FASEB J ; 35(1): e20997, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32892444

RESUMO

Inorganic phosphate (Pi) is an essential nutrient for human health. Due to the changes in our dietary pattern, dietary Pi overload engenders systemic phosphotoxicity, including excessive Pi-related vascular calcification and chronic tissue injury. The molecular mechanisms of the seemingly distinct phenotypes remain elusive. In this study, we investigated Pi-mediated cellular response in HEK293 and HeLa cells. We found that abnormally high Pi directly mediates diverse cellular toxicity in a dose-dependent manner. Up to 10 mM extracellular Pi promotes cell proliferation by activating AKT signaling cascades and augmenting cell cycle progression. By introducing additional Pi, higher than the concentration of 40 mM, we observed significant cell damage caused by the interwoven Pi-related biological processes. Elevated Pi activates mitogen-activated protein kinase (MAPK) signaling, encompassing extracellular signal-regulated kinase 1/2 (ERK1/2), p38 and Jun amino-terminal kinase (JNK), which consequently potentiates Pi triggered lethal epithelial-mesenchymal transition (EMT). Synergistically, high Pi-caused endoplasmic reticulum (ER) stress also contributes to apparent apoptosis. To counteract, Pi-activated AKT signaling promotes cell survival by activating the mammalian target of rapamycin (mTOR) signaling and blocking ER stress. Pharmacologically or genetically abrogating Pi transport, the impact of high Pi-induced cytotoxicity could be reduced. Taken together, abnormally high extracellular Pi results in a broad spectrum of toxicity by rewiring complicated signaling networks that control cell growth, cell death, and homeostasis.


Assuntos
Apoptose/efeitos dos fármacos , Citotoxinas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosfatos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células HEK293 , Células HeLa , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo
16.
Plant J ; 105(4): 924-941, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33184936

RESUMO

Phosphorus absorbed in the form of phosphate (H2 PO4 - ) is an essential but limiting macronutrient for plant growth and agricultural productivity. A comprehensive understanding of how plants respond to phosphate starvation is essential for the development of more phosphate-efficient crops. Here we employed label-free proteomics and phosphoproteomics to quantify protein-level responses to 48 h of phosphate versus phosphite (H2 PO3 - ) resupply to phosphate-deprived Arabidopsis thaliana suspension cells. Phosphite is similarly sensed, taken up and transported by plant cells as phosphate, but cannot be metabolized or used as a nutrient. Phosphite is thus a useful tool for differentiating between non-specific processes related to phosphate sensing and transport and specific responses to phosphorus nutrition. We found that responses to phosphate versus phosphite resupply occurred mainly at the level of protein phosphorylation, complemented by limited changes in protein abundance, primarily in protein translation, phosphate transport and scavenging, and central metabolism proteins. Altered phosphorylation of proteins involved in core processes such as translation, RNA splicing and kinase signaling was especially important. We also found differential phosphorylation in response to phosphate and phosphite in 69 proteins, including splicing factors, translation factors, the PHT1;4 phosphate transporter and the HAT1 histone acetyltransferase - potential phospho-switches signaling changes in phosphorus nutrition. Our study illuminates several new aspects of the phosphate starvation response and identifies important targets for further investigation and potential crop improvement.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fosfatos/metabolismo , Fosfitos/metabolismo , Fosfoproteínas/metabolismo , Proteoma/metabolismo , Arabidopsis/citologia , Arabidopsis/efeitos dos fármacos , Transporte Biológico , Carbono/metabolismo , Respiração Celular , Células Cultivadas , Fosfatos/farmacologia , Fosfitos/farmacologia , Fosforilação , Proteoma/efeitos dos fármacos , Proteômica
17.
J Biosci Bioeng ; 131(3): 234-240, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33189544

RESUMO

Trypsin is a serine protease with important applications such as protein sequencing and tissue dissociation. Preserving protein structure and its activity during freeze-thawing and prolonging its shelf life is one of the most interesting tasks in biochemistry. In the present study, trypsin cryoprotection was achieved by altering buffer composition. Sodium phosphate buffer at pH 8.0 led to pH shift-induced destabilization of trypsin and formation of a molten globule, followed by significant activity loss (about 70%). Potassium phosphate and ammonium bicarbonate buffers at pH 8.0 were used with up to 90% activity recovery rate after 7 freeze-thaw cycles. The addition of non-ionic surfactants Tween 20 and Tween 80 led to up to 99% activity recovery rate. Amide I region changes, corresponding to specific secondary structures in the Fourier transform infrared (FTIR) spectrum, were modest in the case of Tween 20 and Tween 80. On the other hand, the addition of Triton X-100 led to the destabilization of α-helicoidal segments of trypsin structure after 7 freeze-thaw cycles but also increased protein substrate availability.


Assuntos
Congelamento , Tensoativos/farmacologia , Tripsina/metabolismo , Octoxinol/farmacologia , Fosfatos/farmacologia , Compostos de Potássio/farmacologia , Tensoativos/química
18.
Ecotoxicol Environ Saf ; 208: 111462, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33069946

RESUMO

The co-existence of organic pollutants and nanoparticles in the environment may lead to combined biological effects. The joint toxicity of pollutants and nanoparticles has been receiving increasing attention from researchers, but few studies have focused on soil biota due to the complexity of soil matrices. This study investigated the effects of tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) at 0, 5, and 25 mg/kg and nanoparticulate TiO2 (nTiO2) at 0, 500, and 2500 mg/kg in a 3 × 3 factorial arrangement of treatments for 28 days (d) on Eisenia fetida (earthworm). Compared with the control group (the 0 mg/kg TDCIPP + 0 mg/kg nTiO2 treatment), all other single (TDCIPP or nTiO2) and binary (TDCIPP + nTiO2) treatments except for the single 500 mg/kg nTiO2 treatment significantly reduced the weight gain rate of E. fetida. The binary treatments had significantly greater such effect than their corresponding single treatments, exhibiting a synergistic toxicity between TDCIPP and nTiO2 on the growth of E. fetida. Since TDCIPP and nTiO2 had no significant effect on their concentrations in the soil or in E. fetida during binary exposure, the synergistic toxicity could be a result of the superimposition of the toxicity pathways of TDCIPP and nTiO2. Transcriptomic analysis of E. fetida intestinal region revealed that exposure to 25 mg/kg TDCIPP or 2500 mg/kg nTiO2 affected nutrient-related or cell apoptosis and DNA damage related genes, respectively; their co-exposure greatly inhibited genes related to nutrient digestion and absorption, while causing abnormal transcription of genes related to the development and maintenance of E. fetida's muscles, leading to synergistic toxicity. These findings provide new insights into the environmental risks of organophosphorus flame retardants, nanoparticles, and their co-exposure.


Assuntos
Poluentes Ambientais/toxicidade , Nanopartículas/toxicidade , Oligoquetos/fisiologia , Compostos Organofosforados/toxicidade , Titânio/toxicidade , Animais , Apoptose/efeitos dos fármacos , Retardadores de Chama/toxicidade , Oligoquetos/efeitos dos fármacos , Fosfatos/farmacologia , Solo
19.
Proc Natl Acad Sci U S A ; 117(52): 33530-33539, 2020 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-33318202

RESUMO

Two-component systems (TCSs) in bacteria are molecular circuits that allow the perception of and response to diverse stimuli. These signaling circuits rely on phosphoryl-group transfers between transmitter and receiver domains of sensor kinase and response regulator proteins, and regulate several cellular processes in response to internal or external cues. Phosphorylation, and thereby activation, of response regulators has been demonstrated to occur by their cognate histidine kinases but also by low molecular weight phosphodonors such as acetyl phosphate and carbamoyl phosphate. Here, we present data indicating that the intermediates of the de novo syntheses of purines and histidine, 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranosyl 5'-monophosphate (ZMP) and/or 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranosyl 5'-triphosphate (ZTP), activate the response regulator UvrY, by promoting its autophosphorylation at the conserved aspartate at position 54. Moreover, these Z nucleotides are shown to also activate the nonrelated response regulators ArcA, CpxR, RcsB, and PhoQ. We propose that ZMP and/or ZTP act as alarmones for a wide range of response regulators in vivo, providing a novel mechanism by which they could impact gene expression in response to metabolic cues.


Assuntos
Escherichia coli/metabolismo , Nucleotídeos/farmacologia , Transdução de Sinais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Genes Bacterianos , Mutação/genética , Fosfatos/farmacologia , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
20.
Molecules ; 25(21)2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33153127

RESUMO

The development and characterization of biomaterials for bone replacement in case of large defects in preconditioned bone (e.g., osteoporosis) require close cooperation of various disciplines. Of particular interest are effects observed in vitro at the cellular level and their in vivo representation in animal experiments. In the present case, the material-based alteration of the ratio of osteoblasts to osteoclasts in vitro in the context of their co-cultivation was examined and showed equivalence to the material-based stimulation of bone regeneration in a bone defect of osteoporotic rats. Gelatin-modified calcium/strontium phosphates with a Ca:Sr ratio in their precipitation solutions of 5:5 and 3:7 caused a pro-osteogenic reaction on both levels in vitro and in vivo. Stimulation of osteoblasts and inhibition of osteoclast activity were proven during culture on materials with higher strontium content. The same material caused a decrease in osteoclast activity in vitro. In vivo, a positive effect of the material with increased strontium content was observed by immunohistochemistry, e.g., by significantly increased bone volume to tissue volume ratio, increased bone morphogenetic protein-2 (BMP2) expression, and significantly reduced receptor activator of nuclear factor kappa-B ligand (RANKL)/osteoprotegerin (OPG) ratio. In addition, material degradation and bone regeneration were examined after 6 weeks using stage scans with ToF-SIMS and µ-CT imaging. The remaining material in the defects and strontium signals, which originate from areas exceeding the defect area, indicate the incorporation of strontium ions into the surrounding mineralized tissue. Thus, the material inherent properties (release of biologically active ions, solubility and degradability, mechanical strength) directly influenced the cellular reaction in vitro and also bone regeneration in vivo. Based on this, in the future, materials might be synthesized and specifically adapted to patient-specific needs and their bone status.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio , Fêmur , Gelatina , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteoporose/terapia , Fosfatos , Estrôncio , Animais , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Técnicas de Cocultura , Feminino , Fêmur/lesões , Fêmur/metabolismo , Fêmur/patologia , Gelatina/química , Gelatina/farmacologia , Osteoblastos/patologia , Osteoclastos/patologia , Osteoporose/metabolismo , Osteoporose/patologia , Fosfatos/química , Fosfatos/farmacologia , Ratos , Ratos Sprague-Dawley , Estrôncio/química , Estrôncio/farmacologia
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