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1.
Mol Cell ; 81(18): 3749-3759, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34469752

RESUMO

The expression of the urea cycle (UC) proteins is dysregulated in multiple cancers, providing metabolic benefits to tumor survival, proliferation, and growth. Here, we review the main changes described in the expression of UC enzymes and metabolites in different cancers at various stages and suggest that these changes are dynamic and should hence be viewed in a context-specific manner. Understanding the evolvability in the activity of the UC pathway in cancer has implications for cancer-immune cell interactions and for cancer diagnosis and therapy.


Assuntos
Carcinogênese/metabolismo , Transformação Celular Neoplásica/metabolismo , Ureia/metabolismo , Amônia/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Expressão Gênica/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Distúrbios Congênitos do Ciclo da Ureia/metabolismo , Distúrbios Congênitos do Ciclo da Ureia/fisiopatologia
2.
Nutrients ; 13(9)2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34579160

RESUMO

Protein imbalance during pregnancy affects women in underdeveloped and developing countries and is associated with compromised offspring growth and an increased risk of metabolic diseases in later life. We studied in a porcine model the glucose and urea metabolism, and circulatory hormone and metabolite profile of offspring exposed during gestation, to maternal isoenergetic low-high (LP-HC), high-low (HP-LC) or adequate (AP) protein-carbohydrate ratio diets. At birth, LP-HC were lighter and the plasma acetylcarnitine to free carnitine ratios at 1 day of life was lower compared to AP offspring. Plasma urea concentrations were lower in 1 day old LP-HC offspring than HP-LC. In the juvenile period, increased insulin concentrations were observed in LP-HC and HP-LC offspring compared to AP, as was body weight from HP-LC compared to LP-HC. Plasma triglyceride concentrations were lower in 80 than 1 day old HP-LC offspring, and glucagon concentrations lower in 80 than 1 day old AP and HP-LC offspring. Plasma urea and the ratio of glucagon to insulin were lower in all 80 than 1 day old offspring. Aminoacyl-tRNA, arginine and phenylalanine, tyrosine and tryptophan metabolism, histidine and beta-alanine metabolism differed between 1 and 80 day old AP and HP-LC offspring. Maternal protein imbalance throughout pregnancy did not result in significant consequences in offspring metabolism compared to AP, indicating enormous plasticity by the placenta and developing offspring.


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Proteínas na Dieta/administração & dosagem , Fenômenos Fisiológicos da Nutrição Materna , Metaboloma , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Acetilcarnitina/sangue , Animais , Animais Recém-Nascidos/metabolismo , Carnitina/sangue , Carboidratos da Dieta/administração & dosagem , Feminino , Glucose/metabolismo , Teste de Tolerância a Glucose , Masculino , Gravidez , Deficiência de Proteína/metabolismo , Suínos/crescimento & desenvolvimento , Suínos/metabolismo , Triglicerídeos/sangue , Ureia/sangue , Ureia/metabolismo
3.
J Am Heart Assoc ; 10(16): e020480, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34369200

RESUMO

Background Maintaining euvolemia is crucial for improving prognosis in acute decompensated heart failure (ADHF). Although fractional excretion of urea nitrogen (FEUN) is used as a body fluid volume index in patients with acute kidney injury, the clinical impact of FEUN in patients with ADHF remains unclear. This study aimed to investigate whether FEUN can determine the long-term prognosis in patients with ADHF. Methods and Results We retrospectively identified 466 patients with ADHF who had FEUN measured at discharge between April 2011 and December 2018. The primary endpoint was post-discharge all-cause death. Patients were divided into two groups according to a FEUN cut-off value of 35%, commonly used in pre-renal failure. The FEUN <35% (low-FEUN) group included 224 patients (48.1%), and the all-cause mortality rate for the total cohort was 37.1%. The log-rank test revealed that the low-FEUN group had a significantly higher rate of all-cause death compared to the FEUN equal to or greater than 35% (high-FEUN) group (P<0.001). Multivariate Cox proportional hazards model analysis revealed that low-FEUN was associated with post-discharge all-cause death, independently of other heart failure risk factors (hazard ratio, 1.467; 95% CI, 1.030-2.088, P=0.033). The risk of low-FEUN compared to high-FEUN in post-discharge all-cause death was consistent across all subgroups; however, the effects tended to be modified by renal function (threshold: 60 mL/min/1.73 m2, interaction P=0.069). Conclusions Our study suggests that FEUN may be a novel surrogate marker of volume status in patients with ADHF requiring diuretics.


Assuntos
Nitrogênio da Ureia Sanguínea , Creatinina/metabolismo , Insuficiência Cardíaca/metabolismo , Alta do Paciente , Ureia/metabolismo , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Biomarcadores/urina , Creatinina/sangue , Creatinina/urina , Progressão da Doença , Diuréticos/uso terapêutico , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/mortalidade , Humanos , Masculino , Readmissão do Paciente , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Ureia/sangue , Ureia/urina
4.
Eur J Med Chem ; 223: 113678, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34218083

RESUMO

Sepsis, a systemic inflammatory response, caused by pathogenic factors including microorganisms, has high mortality and limited therapeutic approaches. Herein, a new soluble epoxide hydrolase (sEH) inhibitor series comprising a phenyl ring connected to a memantyl moiety via a urea or amide linkage has been designed. A preferential urea pharmacophore that improved the binding properties of the compounds was identified for those series via biochemical assay in vitro and in vivo studies. Molecular docking displayed that 3,5-dimethyl on the adamantyl group in B401 could make van der Waals interactions with residues at a hydrophobic pocket of sEH active site, which might indirectly explain the subnanomolar level activities of memantyl urea derivatives in vitro better than AR-9281. Among them, compound B401 significantly improved the inhibition potency with human and murine sEH IC50 values as 0.4 nM and 0.5 nM, respectively. Although the median survival time of C57BL/6 mice in LPS-induced sepsis model was slightly increased, the survival rate did not reach significant efficacy. Based on safety profile, metabolic stability, pharmacokinetic and in vivo efficacy, B401 demonstrated the proof of potential for this class of memantyl urea-based sEH inhibitors as therapeutic agents in sepsis.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Epóxido Hidrolases/antagonistas & inibidores , Memantina/química , Sepse/tratamento farmacológico , Ureia/análogos & derivados , Animais , Sítios de Ligação , Domínio Catalítico , Modelos Animais de Doenças , Desenho de Fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Epóxido Hidrolases/metabolismo , Feminino , Humanos , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Ratos , Sepse/etiologia , Sepse/mortalidade , Relação Estrutura-Atividade , Taxa de Sobrevida , Ureia/metabolismo , Ureia/uso terapêutico
5.
Am J Physiol Regul Integr Comp Physiol ; 321(3): R377-R384, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34318705

RESUMO

The purpose of this study was to investigate if the cardiovascular system is important for ammonia excretion in the early life stages of zebrafish. Morpholino knockdowns of cardiac troponin T (TNNT2) or vascular endothelial growth factor A (VEGFA) provided morphants with nonfunctional circulation. At the embryonic stage [30-36 h postfertilization (hpf)], ammonia excretion was not constrained by a lack of cardiovascular function. At 2 days postfertilization (dpf) and 4 dpf, morpholino knockdowns of TNNT2 or VEGFA significantly reduced ammonia excretion in all morphants. Expression of rhag, rhbg, and rhcgb showed no significant changes but the mRNA levels of the urea transporter (ut) were upregulated in the 4 dpf morphants. Taken together, rhag, rhbg, rhcgb, and ut gene expression and an unchanged tissue ammonia concentration but an increased tissue urea concentration, suggest that impaired ammonia excretion led to increased urea synthesis. However, in larvae anesthetized with tricaine or clove oil, ammonia excretion was not reduced in the 4 dpf morphants compared with controls. Furthermore, oxygen consumption was reduced in morphants regardless of anesthesia. These results suggest that cardiovascular function is not directly involved in ammonia excretion, but rather reduced activity and external convection may explain reduced ammonia excretion and compensatory urea accumulation in morphants with reduced cardiovascular function.


Assuntos
Sistema Cardiovascular/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Ureia/metabolismo , Animais , Proteínas de Transporte de Cátions/genética , Brânquias/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
6.
Biosensors (Basel) ; 11(6)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201174

RESUMO

The development of in situ analytical devices has gained outstanding scientific interest. A solid sensing membrane composed of 1,2-naphthoquinone-4-sulfonate (NQS) derivatizing reagent embedded into a polymeric polydimethylsiloxane (PDMS) composite was proposed for in situ ammonium (NH4+) and urea (NH2CONH2) analysis in water and urine samples, respectively. Satisfactory strategies were also applied for urease-catalyzed hydrolysis of urea, either in solution or glass-supported urease immobilization. Using diffuse reflectance measurements combined with digital image processing of color intensity (RGB coordinates), qualitative and quantitative analyte detection was assessed after the colorimetric reaction took place inside the sensing membrane. A suitable linear relationship was found between the sensor response and analyte concentration, and the results were validated by a thymol-PDMS-based sensor based on the Berthelot reaction. The suggested sensing device offers advantages such as rapidity, versatility, portability, and employment of non-toxic reagents that facilitate in situ analysis in an energy-efficient manner.


Assuntos
Naftoquinonas/química , Ureia/metabolismo , Urease/metabolismo , Colorimetria , Dimetilpolisiloxanos , Polímeros , Urease/análise , Água/química
7.
J Anim Sci ; 99(8)2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34107039

RESUMO

Urea recycling occurs in all mammalian species and represents an important source of ruminal nitrogen (N) for ruminants fed protein-restricted diets. However, its importance for cattle fed adequate amounts of protein and energy remains unclear. Six Nellore feedlot steers fed concentrate-based diets were used in a 6 × 6 Latin square design with a 3 × 2 factorial arrangement of treatments to evaluate ruminal fermentation, urea kinetics, and N excretion. Treatments consisted of 3 protein sources (PS: soybean meal plus urea [SU], corn gluten meal [CGM], and dry distillers grains [DDG]) and 2 inclusion levels (PL; 11% and 14%). Steers were adapted to the diets for 14 d followed by 8 d of sample collection. Feed intake, fecal output, and urine production were measured from day 18 to day 22 of each period. Blood samples were collected every 6 h on day 18. [15N-15N]-urea was infused into the jugular vein for 82 h over day 19 to day 22, and measurement of 15N in background (day 18) and enriched feces and urine (day 21) were used to evaluate urea kinetics. To evaluate the incorporation of recycled urea N into microbial protein (MICP), ruminal and duodenal fluid were collected on day 22. Steers fed SU diets had lower (P < 0.05) nitrogen use efficiency (NUE), greater (P < 0.05) urea-N entry rate (UER), and tended (P < 0.10) to have greater gastrointestinal entry rate of urea-N (GER) compared with those fed CGM or DDG. In addition, steers fed SU had greater (P < 0.05) urea-N returned to ornithine cycle (ROC) compared with those fed CGM or DDG. Increasing PL tended (P < 0.10) to increase UER. The proportion of total microbial N from recycled urea-N was greater (P < 0.05) for steers fed CGM compared with those fed SU and also greater for steers fed diets with 11% CP than for those fed with 14% CP. Diets with 11% CP can be used for Nellore feedlot cattle fed concentrate-based diets without negatively affecting intake, digestibility, and ruminal fermentation. Moreover, diets containing rumen undegradable protein (RUP) feed sources (CGM or DDG) compared with diets with SU markedly increased NUE, while maintaining microbial protein (MICP) synthesis. Results from this study suggest that the equation adopted by NASEM (NASEM. 2016. Nutrient requirements of beef cattle. 8th revised ed. Washington, DC: The National Academies Press) was not accurate in estimating the urea-N used for anabolism (UUA) in Nellore feedlot cattle fed concentrate-based diets.


Assuntos
Rúmen , Ureia , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Proteínas na Dieta/metabolismo , Digestão , Fermentação , Cinética , Nitrogênio/metabolismo , Rúmen/metabolismo , Ureia/metabolismo
8.
Int J Biol Macromol ; 184: 721-730, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34174306

RESUMO

Aquaporin (AQP) transport solutes across cell membranes in both unicellular and multicellular organisms. In this study, the aquaporin CsPrip was identified in Chilo suppressalis, an important pest of rice. CsPrip was comprised of two variants, CsPrip_v1 and CsPrip_v2; the former variant was <103 bp was shorter than the latter, although both exhibited the same open reading frame (ORF). Transmembrane topology and protein structure analyses showed that CsPrip retained the conserved features of water-selective insect AQPs, including six transmembrane domains, two conserved hydrophobic asparagine-proline-alanine motifs and the aromatic/arginine constriction region. Expression in Xenopus oocytes revealed that CsPrip preferentially transported water and urea instead of trehalose and glycerol. The CsPrip transcript was expressed in multiple organs and tissues of C. suppressalis larvae and was most abundant in the hindgut and Malpighian tubules. CsPrip transcription was highest in male adults and was relatively stable throughout development. CsPrip expression in larvae was significantly altered by thermal stress, and relative humidity levels impacted CsPrip transcription in 3rd and 5th instar larvae. This study confirms that the aquaporin CsPrip performs multiple critical functions in maintaining water equilibrium in C. suppressalis.


Assuntos
Aquaporinas/genética , Aquaporinas/metabolismo , Lepidópteros/metabolismo , Oryza/parasitologia , Processamento Alternativo , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Aquaporinas/química , Feminino , Regulação da Expressão Gênica , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Lepidópteros/genética , Masculino , Modelos Moleculares , Especificidade de Órgãos , Conformação Proteica , Domínios Proteicos , Caracteres Sexuais , Ureia/metabolismo , Água/metabolismo , Xenopus/genética , Xenopus/crescimento & desenvolvimento
9.
J Vis Exp ; (170)2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33871457

RESUMO

Primary hepatocytes are widely used in basic research on liver diseases and for toxicity testing in vitro. The two-step collagenase perfusion procedure for primary hepatocyte isolation is technically challenging, especially in portal vein cannulation. The procedure is also prone to occasional contamination and variations in perfusion conditions due to difficulties in the assembly, optimization, or maintenance of the perfusion setup. Here, a detailed protocol for an improved two-step collagenase perfusion procedure with multiparameter perfusion control is presented. Primary rat hepatocytes were successfully and reliably isolated by taking the necessary technical precautions at critical steps of the procedure, and by reducing the operational difficulty and mitigating the variability of perfusion parameters through the adoption of a special intravenous catheter, standardized sterile disposable tubing, temperature control, and real-time monitoring and alarm system. The isolated primary rat hepatocytes consistently exhibit high cell viability (85%-95%), yield (2-5 x 108 cells per 200-300 g rat) and functionality (albumin, urea and CYP activity). The procedure was complemented by an integrated perfusion system, which is compact enough to be set up in the laminar flow hood to ensure aseptic operation.


Assuntos
Separação Celular/métodos , Hepatócitos , Albuminas/metabolismo , Animais , Sobrevivência Celular , Células Cultivadas , Colagenases , Sistema Enzimático do Citocromo P-450/metabolismo , Hepatócitos/metabolismo , Masculino , Perfusão , Ratos Wistar , Ureia/metabolismo
10.
Genes (Basel) ; 12(3)2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33806889

RESUMO

The objective of this study was to identify genomic regions associated with milk fat percentage (FP), crude protein percentage (CPP), urea concentration (MU) and efficiency of crude protein utilization (ECPU: ratio between crude protein yield in milk and dietary crude protein intake) using grazing, mixed-breed, dairy cows in New Zealand. Phenotypes from 634 Holstein Friesian, Jersey or crossbred cows were obtained from two herds at Massey University. A subset of 490 of these cows was genotyped using Bovine Illumina 50K SNP-chips. Two genome-wise association approaches were used, a single-locus model fitted to data from 490 cows and a single-step Bayes C model fitted to data from all 634 cows. The single-locus analysis was performed with the Efficient Mixed-Model Association eXpedited model as implemented in the SVS package. Single nucleotide polymorphisms (SNPs) with genome-wide association p-values ≤ 1.11 × 10-6 were considered as putative quantitative trait loci (QTL). The Bayes C analysis was performed with the JWAS package and 1-Mb genomic windows containing SNPs that explained > 0.37% of the genetic variance were considered as putative QTL. Candidate genes within 100 kb from the identified SNPs in single-locus GWAS or the 1-Mb windows were identified using gene ontology, as implemented in the Ensembl Genome Browser. The genes detected in association with FP (MGST1, DGAT1, CEBPD, SLC52A2, GPAT4, and ACOX3) and CPP (DGAT1, CSN1S1, GOSR2, HERC6, and IGF1R) were identified as candidates. Gene ontology revealed six novel candidate genes (GMDS, E2F7, SIAH1, SLC24A4, LGMN, and ASS1) significantly associated with MU whose functions were in protein catabolism, urea cycle, ion transportation and N excretion. One novel candidate gene was identified in association with ECPU (MAP3K1) that is involved in post-transcriptional modification of proteins. The findings should be validated using a larger population of New Zealand grazing dairy cows.


Assuntos
Estudo de Associação Genômica Ampla/veterinária , Leite/química , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Animais , Cruzamento , Bovinos , Ácidos Graxos/metabolismo , Feminino , Herbivoria , Proteínas do Leite/metabolismo , Nova Zelândia , Ureia/metabolismo
11.
Int J Mol Sci ; 22(9)2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33925462

RESUMO

Soybean (Glycine max (L.) Merr.) plants form root nodules and fix atmospheric dinitrogen, while also utilizing the combined nitrogen absorbed from roots. In this study, nodulated soybean plants were supplied with 5 mM N nitrate, ammonium, or urea for 3 days, and the changes in metabolite concentrations in the xylem sap and each organ were analyzed. The ureide concentration in the xylem sap was the highest in the control plants that were supplied with an N-free nutrient solution, but nitrate and asparagine were the principal compounds in the xylem sap with nitrate treatment. The metabolite concentrations in both the xylem sap and each organ were similar between the ammonium and urea treatments. Considerable amounts of urea were present in the xylem sap and all the organs among all the treatments. Positive correlations were observed between the ureides and urea concentrations in the xylem sap as well as in the roots and leaves, although no correlations were observed between the urea and arginine concentrations, suggesting that urea may have originated from ureide degradation in soybean plants, possibly in the roots. This is the first finding of the possibility of ureide degradation to urea in the underground organs of soybean plants.


Assuntos
Compostos de Amônio/farmacologia , Nitratos/farmacologia , Soja/efeitos dos fármacos , Soja/metabolismo , Ureia/farmacologia , Alantoína/metabolismo , Aminoácidos/metabolismo , Fixação de Nitrogênio/efeitos dos fármacos , Nodulação/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Açúcares/metabolismo , Ureia/metabolismo , Xilema/efeitos dos fármacos , Xilema/metabolismo
12.
J Med Chem ; 64(9): 5447-5469, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33904752

RESUMO

The BCL-2 family of proteins (including the prosurvival proteins BCL-2, BCL-XL, and MCL-1) is an important target for the development of novel anticancer therapeutics. Despite the challenges of targeting protein-protein interaction (PPI) interfaces with small molecules, a number of inhibitors (called BH3 mimetics) have entered the clinic and the BCL-2 inhibitor, ABT-199/venetoclax, is already proving transformative. For BCL-XL, new validated chemical series are desirable. Here, we outline the crystallography-guided development of a structurally distinct series of BCL-XL/BCL-2 inhibitors based on a benzoylurea scaffold, originally proposed as α-helix mimetics. We describe structure-guided exploration of a cryptic "p5" pocket identified in BCL-XL. This work yields novel inhibitors with submicromolar binding, with marked selectivity toward BCL-XL. Extension into the hydrophobic p2 pocket yielded the most potent inhibitor in the series, binding strongly to BCL-XL and BCL-2 (nanomolar-range half-maximal inhibitory concentration (IC50)) and displaying mechanism-based killing in cells engineered to depend on BCL-XL for survival.


Assuntos
Antineoplásicos/química , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Ureia/análogos & derivados , Proteína bcl-X/antagonistas & inibidores , Animais , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Sítios de Ligação , Compostos de Bifenilo/química , Compostos de Bifenilo/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Humanos , Interações Hidrofóbicas e Hidrofílicas , Concentração Inibidora 50 , Camundongos , Simulação de Dinâmica Molecular , Nitrofenóis/química , Nitrofenóis/metabolismo , Piperazinas/química , Piperazinas/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Relação Estrutura-Atividade , Sulfonamidas/química , Sulfonamidas/metabolismo , Ressonância de Plasmônio de Superfície , Ureia/metabolismo , Ureia/farmacologia , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
13.
Molecules ; 26(7)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33915902

RESUMO

The urea cycle (UC) removes the excess nitrogen and ammonia generated by nitrogen-containing compound composites or protein breakdown in the human body. Research has shown that changes in UC enzymes are not only related to tumorigenesis and tumor development but also associated with poor survival in hepatocellular, breast, and colorectal cancers (CRC), etc. Cytoplasmic ornithine, the intermediate product of the urea cycle, is a specific substrate for ornithine decarboxylase (ODC, also known as ODC1) for the production of putrescine and is required for tumor growth. Polyamines (spermidine, spermine, and their precursor putrescine) play central roles in more than half of the steps of colorectal tumorigenesis. Given the close connection between polyamines and cancer, the regulation of polyamine metabolic pathways has attracted attention regarding the mechanisms of action of chemical drugs used to prevent CRC, as the drug most widely used for treating type 2 diabetes (T2D), metformin (Met) exhibits antitumor activity against a variety of cancer cells, with a vaguely defined mechanism. In addition, the influence of metformin on the UC and putrescine generation in colorectal cancer has remained unclear. In our study, we investigated the effect of metformin on the UC and putrescine generation of CRC in vivo and in vitro and elucidated the underlying mechanisms. In nude mice bearing HCT116 tumor xenografts, the administration of metformin inhibited tumor growth without affecting body weight. In addition, metformin treatment increased the expression of monophosphate (AMP)-activated protein kinase (AMPK) and p53 in both HCT116 xenografts and colorectal cancer cell lines and decreased the expression of the urea cycle enzymes, including carbamoyl phosphate synthase 1 (CPS1), arginase 1 (ARG1), ornithine trans-carbamylase (OTC), and ODC. The putrescine levels in both HCT116 xenografts and HCT116 cells decreased after metformin treatment. These results demonstrate that metformin inhibited CRC cell proliferation via activating AMPK/p53 and that there was an association between metformin, urea cycle inhibition and a reduction in putrescine generation.


Assuntos
Neoplasias Colorretais/metabolismo , Redes e Vias Metabólicas/efeitos dos fármacos , Metformina/farmacologia , Putrescina/biossíntese , Ureia/metabolismo , Animais , Biomarcadores , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Expressão Gênica , Perfilação da Expressão Gênica , Xenoenxertos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
14.
J Gen Physiol ; 153(7)2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33688929

RESUMO

Omecamtiv mecarbil (OM), a direct myosin motor activator, is currently being tested as a therapeutic replacement for conventional inotropes in heart failure (HF) patients. It is known that HF patients exhibit dysregulated ß-adrenergic signaling and decreased cardiac myosin-binding protein C (cMyBPC) phosphorylation, a critical modulator of myocardial force generation. However, the functional effects of OM in conditions of altered cMyBPC phosphorylation have not been established. Here, we tested the effects of OM on force generation and cross-bridge (XB) kinetics using murine myocardial preparations isolated from wild-type (WT) hearts and from hearts expressing S273A, S282A, and S302A substitutions (SA) in the M domain, between the C1 and C2 domains of cMyBPC, which cannot be phosphorylated. At submaximal Ca2+ activations, OM-mediated force enhancements were less pronounced in SA than in WT myocardial preparations. Additionally, SA myocardial preparations lacked the dose-dependent increases in force that were observed in WT myocardial preparations. Following OM incubation, the basal differences in the rate of XB detachment (krel) between WT and SA myocardial preparations were abolished, suggesting that OM differentially affects the XB behavior when cMyBPC phosphorylation is reduced. Similarly, in myocardial preparations pretreated with protein kinase A to phosphorylate cMyBPC, incubation with OM significantly slowed krel in both the WT and SA myocardial preparations. Collectively, our data suggest there is a strong interplay between the effects of OM and XB behavior, such that it effectively uncouples the sarcomere from cMyBPC phosphorylation levels. Our findings imply that OM may significantly alter the in vivo cardiac response to ß-adrenergic stimulation.


Assuntos
Contração Miocárdica , Ureia , Animais , Humanos , Camundongos , Miocárdio/metabolismo , Fosforilação , Ureia/análogos & derivados , Ureia/metabolismo
15.
Biochem Biophys Res Commun ; 553: 1-8, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33752091

RESUMO

BACKGROUND AND AIMS: Hypercholesterolemia is characterized by the elevation of plasma total cholesterol level, especially low-density lipoprotein (LDL) cholesterol. This disease is usually caused by a mutation in genes such as LDL receptor, apolipoprotein B, or proprotein convertase subtilisin/kexin type 9. However, a considerable number of patients with hypercholesterolemia do not have any mutation in these candidate genes. In this study, we examined the difference in the metabolic level between patients with hypercholesterolemia and healthy subjects, and screened the potential biomarkers for this disease. METHODS: Analysis of plasma metabolomics in hypercholesterolemia patients and healthy controls was performed by gas chromatography-mass spectrometry and metabolic correlation networks were constructed using Gephi-0.9.2. RESULTS: First, metabolic profile analysis confirmed the distinct metabolic footprints between the patients and the healthy ones. The potential biomarkers screened by orthogonal partial least-squares discrimination analysis included l-lactic acid, cholesterol, phosphoric acid, d-glucose, urea, and d-allose (Variable importance in the projection > 1). Second, arginine and methionine metabolism were significantly perturbed in hypercholesterolemia patients. Finally, we identified that l-lactic acid, l-lysine, l-glutamine, and l-cysteine had high scores of centrality parameters in the metabolic correlation network. CONCLUSION: Plasma l-lactic acid could be used as a sensitive biomarker for hypercholesterolemia. In addition, arginine biosynthesis and cysteine and methionine metabolism were profoundly altered in patients with hypercholesterolemia.


Assuntos
Biomarcadores/sangue , Biomarcadores/metabolismo , Hipercolesterolemia/sangue , Hipercolesterolemia/metabolismo , Metabolômica , Adolescente , Adulto , Arginina/metabolismo , Estudos de Casos e Controles , Colesterol/metabolismo , Cisteína/metabolismo , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Glucose/metabolismo , Glutamina/metabolismo , Humanos , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Lisina/metabolismo , Masculino , Metionina/metabolismo , Pessoa de Meia-Idade , Ácidos Fosfóricos/metabolismo , Ureia/metabolismo , Adulto Jovem
16.
J Sci Food Agric ; 101(13): 5520-5528, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33719065

RESUMO

BACKGROUND: A one-off application of combining controlled-release urea (CRU) and conventional urea has been recommended for the reduction of nitrogen (N) loss and improvement of grain yield. However, the effects of combining CRU and urea with different surface mulching has not been studied in detail, and the underlying agronomical and physiological mechanisms need to be more clearly understood. RESULT: A 3-year field study was conducted to determine the effects of combining CRU and urea with different surface mulching on dry matter, N accumulation and translocation, nitrate nitrogen (NO3 - -N) residuals and loss in maize grown under rain-fed conditions. Three surface mulching [plastic film mulching (FM), straw mulching (SM) and no mulching (NM)] as well as three N fertilization [combining CRU and urea with 1:2 as the baseline application (NC), a split urea application with 4:3:3 (NU) and a N control (N0)] were used. The FM under NC fertilization increased N uptake, decreased NO3 - -N residual in the deep soil layer, and decreased N loss. The FM, SM and NM under NC fertilization increased 3-year mean grain yields by 5.8%, 4.0% and 4.6%, respectively, compared to that under NU fertilization. The FM under NC fertilization showed the highest grain yield and economic return. CONCLUSION: Properly managing N application by mixing CRU and urea in a one-off application combined with plastic film mulching may have the potential to provide a better compromise among grain yield, N loss and economic returns for maize in rain-fed farmland. © 2021 Society of Chemical Industry.


Assuntos
Produção Agrícola/métodos , Preparações de Ação Retardada/metabolismo , Ureia/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Produção Agrícola/instrumentação , Preparações de Ação Retardada/análise , Fertilizantes/análise , Chuva , Solo/química , Ureia/análise , Água/análise , Água/metabolismo
17.
Appl Environ Microbiol ; 87(11)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33741630

RESUMO

The widely prescribed pharmaceutical metformin and its main metabolite, guanylurea, are currently two of the most common contaminants in surface and wastewater. Guanylurea often accumulates and is poorly, if at all, biodegraded in wastewater treatment plants. This study describes Pseudomonas mendocina strain GU, isolated from a municipal wastewater treatment plant, using guanylurea as its sole nitrogen source. The genome was sequenced with 36-fold coverage and mined to identify guanylurea degradation genes. The gene encoding the enzyme initiating guanylurea metabolism was expressed, and the enzyme was purified and characterized. Guanylurea hydrolase, a newly described enzyme, was shown to transform guanylurea to one equivalent (each) of ammonia and guanidine. Guanidine also supports growth as a sole nitrogen source. Cell yields from growth on limiting concentrations of guanylurea revealed that metabolism releases all four nitrogen atoms. Genes encoding complete metabolic transformation were identified bioinformatically, defining the pathway as follows: guanylurea to guanidine to carboxyguanidine to allophanate to ammonia and carbon dioxide. The first enzyme, guanylurea hydrolase, is a member of the isochorismatase-like hydrolase protein family, which includes biuret hydrolase and triuret hydrolase. Although homologs, the three enzymes show distinct substrate specificities. Pairwise sequence comparisons and the use of sequence similarity networks allowed fine structure discrimination between the three homologous enzymes and provided insights into the evolutionary origins of guanylurea hydrolase.IMPORTANCE Metformin is a pharmaceutical most prescribed for type 2 diabetes and is now being examined for potential benefits to COVID-19 patients. People taking the drug pass it largely unchanged, and it subsequently enters wastewater treatment plants. Metformin has been known to be metabolized to guanylurea. The levels of guanylurea often exceed that of metformin, leading to the former being considered a "dead-end" metabolite. Metformin and guanylurea are water pollutants of emerging concern, as they persist to reach nontarget aquatic life and humans, the latter if it remains in treated water. The present study has identified a Pseudomonas mendocina strain that completely degrades guanylurea. The genome was sequenced, and the genes involved in guanylurea metabolism were identified in three widely separated genomic regions. This knowledge advances the idea that guanylurea is not a dead-end product and will allow for bioinformatic identification of the relevant genes in wastewater treatment plant microbiomes and other environments subjected to metagenomic sequencing.


Assuntos
Proteínas de Bactérias/metabolismo , Guanidina/análogos & derivados , Hidrolases/metabolismo , Redes e Vias Metabólicas , Metformina/metabolismo , Ureia/análogos & derivados , Poluentes Químicos da Água/metabolismo , Amônia/metabolismo , Proteínas de Bactérias/genética , Biodegradação Ambiental , Biomineralização , Genoma Bacteriano/genética , Guanidina/metabolismo , Hidrolases/genética , Família Multigênica , Pseudomonas mendocina/genética , Pseudomonas mendocina/isolamento & purificação , Pseudomonas mendocina/metabolismo , Especificidade por Substrato , Ureia/metabolismo , Águas Residuárias/microbiologia
18.
J Anim Physiol Anim Nutr (Berl) ; 105(6): 1014-1023, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33742735

RESUMO

The experiment was designed to study the use of rambutan (Nephelium lappaceum) fruit peel powder (RP) with urea (U) supplementation on rumen fermentation, digestibility, methane (CH4 ) production, milk production and composition in lactating dairy cows. Four Holstein crossbred lactating dairy cows, with starting liveweight of 450 ± 15 kg with 130 ± 10 DIM (days-in-milk), were randomly allocated to respective treatments: without supplementation (control; T1), supplementation of urea (U) at 90 g/hd/day (T2), supplementation of RP at 450 g/hd/day (T3) and supplementation of RPU (RP at 450 g/hd/day and U 90 g/hd/day) (T4), respectively, using a 4 × 4 Latin square design. The results showed that the U, RP and RPU supplementation did not change feed intakes (p > 0.05) and digestibilities of DM and OM were similar. However, digestibilities of CP and NDF were increased in the U and RPU groups (p < 0.05). Acetate production was decreased, while propionate production was dramatically increased (p < 0.05) in both the RP and RPU groups respectively. Notably, the ratio of C2 :C3 , protozoal population and CH4 production was reduced in both the RP and RPU groups. In addition, nitrogen intake and nitrogen excretion were significantly higher while nitrogen retention was increased in the U and RPU groups. Allantoin excretion and absorption, microbial protein synthesis and efficiency of microbial N supply were increased in the U and RPU supplementation groups (p < 0.05). Furthermore, milk yield, milk fat and total solids were significantly enhanced in the U and RPU groups (p < 0.05). Moreover, the 3.5% FCM was increased (p < 0.05) while milk protein, lactose, solids-not-fat and milk urea nitrogen were not altered (p > 0.05). Supplementation of either U or RPU significantly improved fibre digestibilities, rumen fermentation, microbial protein synthesis, reduced protozoal population, mitigated CH4 production and enhanced milk yield and milk composition.


Assuntos
Rúmen , Sapindaceae , Animais , Bovinos , Dieta/veterinária , Digestão , Fermentação , Frutas , Lactação , Metano/metabolismo , Pós , Rúmen/metabolismo , Ureia/metabolismo
19.
Asian Pac J Cancer Prev ; 22(3): 909-918, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33773557

RESUMO

OBJECTIVE: ß-eudesmol is the active compound isolated from Atractylodes lancea (Thunb) D.C. The actions of this compound against cholangiocarcinoma (CCA) cells include anti-angiogenesis and anti-cell proliferation and growth. For more understanding of the molecular targets of action of ß-eudesmol, the CCA cells (CL-6) were exposed to ß-eudesmol for 24 and 48 hours. METHODS: Proteins and metabolites from the intra- and extra-cellular components of the CL-6 cells were extracted and identified by LC-MS/MS.  Protein analysis was performed using the Venn diagram (protein grouping), PANTHER (gene ontology), and STITCH software (protein-protein interaction). Metabolite analysis including their interactions with proteins, was performed using MetaboAnalyst software. RESULTS: The analysis showed that the actions of ß-eudesmol were associated with various biological processes particularly apoptosis and cell cycle. These included blood coagulation, wound healing, DNA repair, PI3K-Akt signaling pathway, immune system process, MAPK cascade, urea cycle, purine metabolism, ammonia recycling, and methionine metabolism. CONCLUSION: Possible molecular targets of action of ß-eudesmol against CL-6 for cell apoptosis induction were TNFRSf6, cytochrome C, BAX3, DHCR24, CD29, and ATP.  On the other hand, possible targets for cell cycle arrest induction were CDKN2B, MLF1, TFDP2, CDK11-p110, and nicotinamide.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias dos Ductos Biliares/metabolismo , Colangiocarcinoma/metabolismo , Metabolômica , Proteômica , Sesquiterpenos de Eudesmano/farmacologia , Amônia/metabolismo , Coagulação Sanguínea , Linhagem Celular Tumoral , Reparo do DNA , Humanos , Sistema de Sinalização das MAP Quinases , Metionina/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Purinas/metabolismo , Transdução de Sinais , Ureia/metabolismo , Cicatrização
20.
Anim Reprod Sci ; 226: 106703, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33549887

RESUMO

Yearling Angus bulls (n = 36) were assigned one of three diets: 1) 60 % concentrate as corn (CON, 0.2 % S, 13.4 % CP; n = 12); 2) 60 % dried corn distiller's grains plus solubles (60DDGS 0.5 % S, 22.0 % CP; n = 12); 3) CON diet + equivalent sulfur of 60DDGS as CaSO4 (SULF, 0.5 % S, 13.9 % CP; n = 12) to evaluate effects of feeding 60 % DDGS or sulfur as CaSO4 on mineral and metabolite concentrations in serum and seminal plasma. Treatment × day interactions (P < 0.03) were observed for serum Cu, Se, and Mo. For Cu at d 112, lesser (P < 0.01) concentrations were observed in bulls fed the 60DDGS compared to SULF and CON diets. There were greater (P < 0.01) concentrations of Se at d 112 in bulls fed 60DDGS than CON and SULF diets. Concentrations of Mo were greater at d 56 and 112 (P < 0.01) in bulls fed CON compared to SULF and 60DDGS diets. In seminal plasma, there were treatment × day interactions (P < 0.02) for Cu and Mo. For Cu, at d 112, there was a lesser (P < 0.01) concentration in the bulls fed SULF compared to CON and 60DDGS diets. For Mo, there was a greater (P < 0.01) concentration in bulls fed the CON than 60DDGS and SULF diets at d 56 and 112. Changes in mineral and metabolite concentrations may have effects on bull reproductive performance when there is a relatively greater dietary sulfur content.


Assuntos
Ração Animal/análise , Sulfato de Cálcio/administração & dosagem , Bovinos , Dieta/veterinária , Minerais/sangue , Sêmen/química , Aminoácidos/química , Aminoácidos/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Sulfato de Cálcio/farmacologia , Suplementos Nutricionais , Glucose/química , Glucose/metabolismo , Masculino , Minerais/metabolismo , Ureia/metabolismo , Zea mays
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