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1.
Chempluschem ; 88(1): e202200286, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36591998

RESUMO

Nanozymes have advantages over natural enzymes in terms of efficiency, stability, and economy. MVSM (Mixed Valence State MOF) is a nano-oxidase with uricase-like activity that may catalyze uric acid (UA) in the body into allantoin and H2 O2 to treat gout and hyperuricemia by substituting natural uricase. However, it cannot specifically identify and choose UA. To increase the selectivity and affinity of MVSM for UA, the composite material MVSM@MIP is innovatively synthesized using a new synthetic approach termed the "two-step synthesis method," which may prevent UA from being oxidized by MVSM during manufacture in this study. At the same time, this study also provides experimental proof of the effective creation of the material, the advantages of the "two-step synthesis approach," and the high selectivity and affinity of MVSM@MIP for UA. Based on these findings, the suggested technique may be used to effectively catalyze uric acid in human urine with high activity.


Assuntos
Hiperuricemia , Ácido Úrico , Humanos , Ácido Úrico/urina , Polímeros Molecularmente Impressos , Urato Oxidase
2.
Curr Oncol ; 29(12): 9826-9832, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36547186

RESUMO

Management of tumor lysis syndrome (TLS) associated with cancer chemotherapy for malignant tumors is important because of its potentially fatal course. The use of rasburicase, a recombinant urate oxidase, is recommended for TLS; however, because rasburicase is an enzymatic drug, one should be cautious of anaphylaxis during administration. Using claims data in Japan, we investigated the rate of rasburicase re-administration and the occurrence of anaphylaxis during re-administration in patients with hematopoietic malignancies in a multicenter setting. Re-administration of rasburicase was defined as administration after an interval of 21 days from the first dose. Of 373 patients, 18 were re-administered rasburicase (re-administration rate: 4.8%). No patient developed anaphylaxis. The median number of days from the first to the last dose of rasburicase was 256.5 days (interquartile range: 138.8-455.8 days). The median daily dose was 7.5 mg (4.5-11.3 mg), and the median total dose was 33.8 mg (19.1-64.1 mg). This claims database analysis revealed that the re-administration rate of rasburicase was low in Japanese patients with hematopoietic malignancies, suggesting that rasburicase was being used appropriately, and that associated anaphylaxis was not observed.


Assuntos
Anafilaxia , Neoplasias Hematológicas , Proteínas Recombinantes , Síndrome de Lise Tumoral , Urato Oxidase , Humanos , Neoplasias Hematológicas/tratamento farmacológico , Síndrome de Lise Tumoral/complicações , Síndrome de Lise Tumoral/tratamento farmacológico , Urato Oxidase/administração & dosagem , Urato Oxidase/efeitos adversos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico , Anafilaxia/epidemiologia , Anafilaxia/etiologia
3.
Arthritis Res Ther ; 24(1): 281, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36575505

RESUMO

BACKGROUND: Uncontrolled/refractory gout patients are recalcitrant/intolerant to oral urate-lowering therapies (ULTs), experiencing frequent gout flares, functionally limiting tophi, and low quality of life. Pegloticase lowers urate, but anti-pegloticase antibodies limit urate-lowering efficacy and increase infusion reaction (IR) risk. Immunomodulator + pegloticase co-administration may improve treatment response rates, with 79% of MIRROR open-label trial (MIRROR-OL, pegloticase + oral methotrexate) participants meeting 6-month response criteria. Exploratory outcomes from MIRROR-OL are described here. METHODS: Adults with uncontrolled gout (serum urate [SU] ≥ 6 mg/dL and ULT-intolerance/recalcitrance or functionally limiting tophi) were included. Oral methotrexate (15 mg/week) was administered 4 weeks before and during pegloticase treatment (biweekly 8 mg infusion, ≤ 52 weeks). Exploratory outcomes included change from baseline (CFB) in number of affected joints, Health Assessment Questionnaires (HAQs), and Gout Global Assessments. RESULTS: Fourteen patients received ≥ 1 pegloticase infusion, with 13 included in 52-week analyses (1 enrolled before treatment-extension amendment, exited at 24 weeks). Three patients prematurely exited due to SU rise; 10 completed 52-week evaluations (8 completed 52 weeks of co-therapy, 2 completed 24 weeks [met treatment goals]). At 52 weeks, SU averaged 1.1 ± 2.5 mg/dL, with improvements in HAQ pain and health (CFB: - 33.6 and - 0.7, respectively), Patient and Physician Global Assessments (CFB: - 4.6 and - 5.7, respectively), and joint involvement (CFB: - 5.6, - 8.4, - 6.0 tender, swollen, tophi-affected joints, respectively). Two patients underwent dual-energy computed tomography, showing concomitant monosodium urate volume reductions. All patients had ≥ 1 AE, with 92.9% experiencing acute flare. One mild IR ("cough") occurred and no new safety signals were identified. CONCLUSION: Pegloticase + methotrexate co-therapy resulted in sustained SU-lowering with meaningful improvements in clinical measures, urate burden, and patient-reported outcomes. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03635957).


Assuntos
Gota , Ácido Úrico , Adulto , Humanos , Metotrexato/uso terapêutico , Supressores da Gota/uso terapêutico , Qualidade de Vida , Gota/tratamento farmacológico , Gota/induzido quimicamente , Polietilenoglicóis/efeitos adversos , Urato Oxidase/uso terapêutico , Resultado do Tratamento
4.
Genes (Basel) ; 13(12)2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36553446

RESUMO

Gout is caused by elevated serum urate leading to the deposition of monosodium urate (MSU) crystals that can trigger episodes of acute inflammation. Humans are sensitive to developing gout because they lack a functional urate-metabolizing enzyme called uricase/urate oxidase (encoded by the UOX gene). A hallmark of long-standing disease is tophaceous gout, characterized by the formation of tissue-damaging granuloma-like structures ('tophi') composed of densely packed MSU crystals and immune cells. Little is known about how tophi form, largely due to the lack of suitable animal models in which the host response to MSU crystals can be studied in vivo long-term. We have previously described a larval zebrafish model of acute gouty inflammation where the host response to microinjected MSU crystals can be live imaged within an intact animal. Although useful for modeling acute inflammation, crystals are rapidly cleared following a robust innate immune response, precluding analysis at later stages. Here we describe a zebrafish uox null mutant that possesses elevated urate levels at larval stages. Uricase-deficient 'hyperuricemic' larvae exhibit a suppressed acute inflammatory response to MSU crystals and prolonged in vivo crystal persistence. Imaging of crystals at later stages reveals that they form granuloma-like structures dominated by macrophages. We believe that uox-/- larvae will provide a useful tool to explore the transition from acute gouty inflammation to tophus formation, one of the remaining mysteries of gout pathogenesis.


Assuntos
Gota , Ácido Úrico , Humanos , Animais , Peixe-Zebra/genética , Urato Oxidase/genética , Gota/genética , Inflamação
6.
Biochem Biophys Res Commun ; 630: 41-49, 2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36137324

RESUMO

Hyperuricemia animal models have long been used for evaluating food-derived anti-hyperuricemia compounds. Fructose and potassium oxonate are commonly used for developing hyperuricemia mouse model. Recent research also developed spontaneous hyperuricemia model by uricase knockout (Uox-/-). In this work, we evaluated 3 kinds of models with the same gene background to illustrate the differences between the treatments. Unlike the uric acid levels in potassium oxonate (224.79 ± 33.62 µmol/L) and Uox-/- groups (458.39 ± 38.29 µmol/L), fructose treatment did not lead to higher serum uric acid level (174.93 ± 30.46 µmol/L) comparing to the control group (153.53 ± 40.96 µmol/L). However, abnormal glycometabolism only developed in the fructose and the Uox-/- group. In addition, anemia, inflammasome and severe renal injury occurred in the Uox-/- group. The Uox-/- mice were then treated with puerarin and allopurinol, and found that puerarin could reduce serum uric acid and alleviated the serious renal damage associated with high uric acid. Thus, the Uox-/- mice could be a suitable model for screening and evaluating anti-hyperuricemia compounds.


Assuntos
Hiperuricemia , Ácido Úrico , Alopurinol , Animais , Modelos Animais de Doenças , Frutose , Hiperuricemia/tratamento farmacológico , Inflamassomos , Camundongos , Urato Oxidase/genética
7.
Obesity (Silver Spring) ; 30(10): 1917-1926, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36150210

RESUMO

Sixty years ago, the geneticist James Neel proposed that the epidemics of obesity and diabetes today may have evolutionary roots. Specifically, he suggested that our ancestors may have accumulated mutations during periods of famine that provided a survival advantage at that time. However, the presence of this "thrifty genotype" in today's world, where food is plentiful, would predispose us to obesity and diabetes. The "thrifty gene" hypothesis, attractive to some, has been challenged over the years. The authors have previously postulated that the loss of the uricase gene, resulting in a rise in serum and intracellular uric acid levels, satisfies the criteria of a thrifty genotype mutation. This paper reviews and brings up-to-date the evidence supporting the hypothesis and discusses the current arguments that challenge this hypothesis. Although further studies are needed to test the hypothesis, the evidence supporting a loss of uricase as a thrifty gene is substantial and supports a role for evolutionary biology in the pathogenesis of the current obesity and diabetes epidemics.


Assuntos
Urato Oxidase , Ácido Úrico , Evolução Biológica , Genótipo , Humanos , Obesidade/epidemiologia , Obesidade/genética , Urato Oxidase/genética
8.
Int J Rheum Dis ; 25(12): 1395-1407, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36082436

RESUMO

AIM: Jian Pi Shen Shi Formula (JPSSF) is a beneficial treatment for hyperuricemia and related tissue damage in the clinical setting. This study was designed to investigate its therapeutic potential and underlying mechanisms in uricase-deficient rats (Uox-/- rats). METHODS: Uox-/- rats were used to assess the therapeutic potential of JPSSF on hyperuricemia. Protein extracts from renal tissues of a Uox-/- group and a JPSSF group were analyzed using tandem mass tag labeling quantitative proteomic workflow. Collagen deposition in Uox-/- rat kidneys was analyzed by Masson trichromatic staining. The gene expression associated with collagen-binding-related signaling pathways in the kidneys was further explored using quantitative polymerase chain reaction assay. The protein expressions of collagen 1a1 (col1a1), col6a1, and α-smooth muscle actin were measured by Western blotting and immunohistochemistry. RESULTS: JPSSF significantly decreased renal function indices and alleviated renal injuries. The action of JPSSF was manifested by down-regulation of col6a1 and interleukin-1 receptor-associated kinase-like 2, which blocked the binding sites on collagen and further prevented kidney injury. The anti-renal fibrosis effect of JPSSF was confirmed by reducing the collagen deposition and hydroxyproline concentrations. JPSSF treatment also intensely down-regulated the mRNA and protein expressions of col6a1, col1a1, and α-smooth muscle actin, which inhibited the function of the collagen-binding-related signaling pathway. CONCLUSION: Our results indicated that JPSSF notably ameliorated hyperuricemia and related renal fibrosis in Uox-/- rats through lowering uric acid and down-regulating the function of the collagen-binding pathway. This suggested that JPSSF is a potential empirical formula for treating hyperuricemia and accompanying renal fibrosis.


Assuntos
Hiperuricemia , Nefropatias , Ratos , Animais , Hiperuricemia/complicações , Hiperuricemia/tratamento farmacológico , Urato Oxidase/metabolismo , Urato Oxidase/farmacologia , Urato Oxidase/uso terapêutico , Actinas/metabolismo , Proteômica , Nefropatias/tratamento farmacológico , Nefropatias/etiologia , Nefropatias/prevenção & controle , Fibrose , Rim/patologia , Transdução de Sinais , Colágeno/metabolismo
9.
Front Immunol ; 13: 931087, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36177037

RESUMO

Aim: Numerous reports have demonstrated the key importance of macrophage-elicited metabolic inflammation in insulin resistance (IR). Our previous studies confirmed that hyperuricemia or high uric acid (HUA) treatment induced an IR state in several peripheral tissues to promote the development of type 2 diabetes mellitus (T2DM). However, the effect of HUA on glucose uptake and the insulin sensitivity of macrophages and its mechanism is unclear. Methods: To assess systemic IR, we generated hyperuricemic mice by urate oxidase knockout (UOX-KO). Then, glucose/insulin tolerance, the tissue uptake of 18F-fluorodeoxyglucose, body composition, and energy balance were assessed. Glucose uptake of circulating infiltrated macrophages in the liver was evaluated by glucose transporter type 4 (GLUT-4) staining. Insulin sensitivity and the insulin signaling pathway of macrophages were demonstrated using the 2-NBDG kit, immunoblotting, and immunofluorescence assays. The immunoprecipitation assay and LC-MS analysis were used to determine insulin receptor substrate 2 (IRS2) levels and its interacting protein enrichment under HUA conditions. Results: Compared to WT mice (10 weeks old), serum uric acid levels were higher in UOX-KO mice (WT, 182.3 ± 5.091 µM versus KO, 421.9 ± 45.47 µM). Hyperuricemic mice with metabolic disorders and systemic IR showed inflammatory macrophage recruitment and increased levels of circulating proinflammatory cytokines. HUA inhibited the nuclear translocation of GLUT-4 in hepatic macrophages, restrained insulin-induced glucose uptake and glucose tolerance, and blocked insulin IRS2/PI3K/AKT signaling. Meanwhile, HUA mediated the IRS2 protein degradation pathway and activated AMPK/mTOR in macrophages. LC-MS analysis showed that ubiquitination degradation could be involved in IRS2 and its interacting proteins to contribute to IR under HUA conditions. Conclusion: The data suggest that HUA-induced glucose intolerance in hepatic macrophages contributed to insulin resistance and impaired the insulin signaling pathway via IRS2-proteasome degradation.


Assuntos
Diabetes Mellitus Tipo 2 , Intolerância à Glucose , Hiperuricemia , Resistência à Insulina , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Citocinas/metabolismo , Fluordesoxiglucose F18 , Glucose/metabolismo , Intolerância à Glucose/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Hiperuricemia/metabolismo , Insulina/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo , Células de Kupffer/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Urato Oxidase , Ácido Úrico/farmacologia
10.
Arthritis Res Ther ; 24(1): 208, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-36008814

RESUMO

BACKGROUND: Publications suggest immunomodulation co-therapy improves responder rates in uncontrolled/refractory gout patients undergoing pegloticase treatment. The MIRROR open-label trial showed a 6-month pegloticase + methotrexate co-therapy responder rate of 79%, compared to an established 42% pegloticase monotherapy responder rate. Longer-term efficacy/safety data are presented here. METHODS: Uncontrolled gout patients (serum urate [SU] ≥ 6 mg/dL and SU ≥ 6 mg/dL despite urate-lowering therapy [ULT], ULT intolerance, or functionally-limiting tophi) were included. Patients with immunocompromised status, G6PD deficiency, severe kidney disease, or methotrexate contraindication were excluded. Oral methotrexate (15 mg/week) and folic acid (1 mg/day) were administered 4 weeks before and during pegloticase therapy. Twelve-month responder rate (SU < 6 mg/dL for ≥ 80% during month 12), 52-week change from baseline in SU, and extended safety were examined. Efficacy analyses were performed for patients receiving ≥ 1 pegloticase infusion. Pharmacokinetics (PK)/anti-drug antibodies (ADAs) were examined and related to efficacy/safety findings. RESULTS: Fourteen patients were included (all male, 49.3 ± 8.7 years, 13.8 ± 7.4-year gout history, pre-therapy SU 9.2 ± 2.5 mg/dL). Three patients were non-responders and discontinued study treatment before 24 weeks, one patient exited the study per protocol at 24 weeks (enrolled prior to treatment extension amendment), and 10 remained in the study through week 52. Of the 10, 8 completed 52 weeks of pegloticase + methotrexate and were 12-month responders. The remaining two discontinued pegloticase + methotrexate at week 24 (met treatment goals) and stayed in the study under observation (allopurinol prescribed at physicians' discretion); one remained a responder at 12 months. At 52 weeks, change from baseline in SU was - 8.2 ± 4.1 mg/dL (SU 1.1 ± 2.4 mg/dL, n = 10). Gout flares were common early in treatment but progressively decreased while on therapy (weeks 1-12, 13/14 [92.9%]; weeks 36-52, 2/8 [25.0%]). One patient recovered from sepsis (serious AE). Two non-responders developed high ADA titers; fewer patients had trough concentrations (Cmin) below the quantitation limit (BQL), and the median Cmin was higher (1.03 µg/mL vs. BQL) than pegloticase monotherapy trials. CONCLUSIONS: Pegloticase + methotrexate co-therapy was well-tolerated over 12 months, with sustained SU lowering, progressive gout flare reduction, and no new safety concerns. Antibody/PK findings suggest methotrexate attenuates ADA formation, coincident with higher treatment response rates. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03635957 . Registered on 17 August 2018.


Assuntos
Gota , Gota/tratamento farmacológico , Supressores da Gota/efeitos adversos , Humanos , Masculino , Metotrexato/uso terapêutico , Polietilenoglicóis/uso terapêutico , Exacerbação dos Sintomas , Resultado do Tratamento , Urato Oxidase/efeitos adversos , Ácido Úrico
11.
Mikrochim Acta ; 189(9): 326, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35948696

RESUMO

In a new approach, we considered the special affinity between Ni and poly-histidine tags of recombinant urate oxidase to utilize Ni-MOF for immobilizing the enzyme. In this study, a carbon paste electrode (CPE) was modified by histidine-tailed urate oxidase (H-UOX) and nickel-metal-organic framework (Ni-MOF) to construct H-UOX/Ni-MOF/CPE, which is a rapid, sensitive, and simple electrochemical biosensor for UA detection. The use of carboxy-terminal histidine-tailed urate oxidase in the construction of the electrode allows the urate oxidase enzyme to be positioned correctly in the electrode. This, in turn, enhances the efficiency of the biosensor. Characterization was carried out by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET), and field emission scanning electron microscopy (FE-SEM). At optimum conditions, the biosensor provided a short response time, linear response within 0.3-10 µM and 10-140 µM for UA with a detection limit of 0.084 µM, repeatability of 3.06%, and reproducibility of 4.9%. Furthermore, the biosensor revealed acceptable stability and selectivity of UA detection in the presence of the commonly coexisted ascorbic acid, dopamine, L-cysteine, urea, and glucose. The detection potential was at 0.4 V vs. Ag/AgCl.


Assuntos
Técnicas Biossensoriais , Urato Oxidase , Técnicas Biossensoriais/métodos , Carbono/química , Eletrodos , Enzimas Imobilizadas/química , Histidina , Reprodutibilidade dos Testes , Urato Oxidase/química , Ácido Úrico
12.
Sci Rep ; 12(1): 12033, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35835916

RESUMO

In this study, we introduce a uricase-immobilized paper (UOx--paper) integrated electrochemical sensor for detection of uric acid (UA) in saliva. The UOx was immobilized on the detection zone in the wax-patterned paper substrate. This UOx-paper was integrated with a Prussian blue--modified, screen-printed carbon electrode after electropolymerization of o-phenylenediamine to construct an electrochemical cell for small-volume (20 µL) of samples. First, we optimized the fabrication conditions of UOx-paper. Next, the amperometric response of the UOx-paper-based electrochemical UA sensor was analyzed using a known concentration of UA standard solution in artificial saliva at an applied potential of - 0.1 V (versus Ag pseudo-reference electrode). The UOx--paper based electrochemical UA sensor showed a sensitivity of 4.9 µA·mM-1 in a linear range of 50 to 1000 µM (R2 = 0.998), high selectivity and good reproducibility, as well as a limit of detection of 18.7 µM (0.31 mg/dL) UA. Finally, we quantified the UA levels in undiluted saliva samples of healthy controls (n = 20) and gout patients (n = 8). The levels were correlated with those measured with conventional salivary UA enzymatic assays as well as serum UA levels. The UOx-paper-based electrochemical UA sensor is a user-friendly and convenient tool to assess salivary UA levels.


Assuntos
Técnicas Biossensoriais , Urato Oxidase , Técnicas Eletroquímicas , Eletrodos , Humanos , Reprodutibilidade dos Testes , Saliva , Ácido Úrico
13.
Luminescence ; 37(9): 1524-1531, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35815832

RESUMO

In this work, a highly efficient electrochemiluminescence (ECL) biosensor was developed based on the nanosponge-hydrogel system for uric acid (UA) detection. First, the nanosponge consisted of polylactic acid glycolic acid (PLGA) nanoparticles immobilized with MoS2 quantum dots (QDs) and urate oxidase (UAO). The marked loading capability of PLGA nanoparticles enables loading many biomolecules and QDs for the specific recognition of UA. Urate oxidase on the nanosponge can catalyze UA to generate H2 O2 in situ, which further triggers the ECL signal for the MoS2 QDs. Furthermore, the biocompatible acrylamide-based hydrogel not only effectively retained the functionalities of the chimeric nanosponge-hydrogel, but also provided structural integrity and engineering flexibility on the electrode for ECL sensing applications. In addition, there were many ester groups and amide bonds in the nanosponge-hydrogel structure. Therefore, many electron can be excited in the ECL process due to the large number of lone electron pairs on oxygen and nitrogen atoms. This resulted in a seven-fold ECL enhancement of the MoS2 QDs. Finally, the nanosponge-hydrogel structure-based ECL biosensor was successfully used in real clinical serum assays. This showed a good analytical performance for UA detection (100-500 µmol/L) with a limit of detection of 20 µmol/L.


Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Hidrogéis , Medições Luminescentes/métodos , Molibdênio/química , Pontos Quânticos/química , Urato Oxidase , Ácido Úrico
14.
J Physiol Biochem ; 78(3): 679-687, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35674867

RESUMO

Conventional chemotherapy plays a key role in hepatocellular carcinoma (HCC) treatment, however, with intrinsic or acquired chemoresistance being a major constraint. Here, we aimed to identify potential target to reverse such chemoresistance. In the present study, we found significant difference in uridine monophosphate synthetase (UMPS) expression between 5-FU resistant and sensitive HCC cell lines and the overexpression or downregulation of UMPS impacted 5-FU response in HCC cells. We further found that inhibition of UMPS activity with uric acid at concentration present in human plasma decreased the 5-FU sensitivity of HCC cells, while reduction of uric acid levels with uricase improved the 5-FU sensitivity of HCC cells as well as colorectal cancer cells. In vivo studies also suggested that modulation of uric acid levels did affect 5-FU sensitivity of tumors. These data indicated that UMPS was correlated with the 5-FU resistance in HCC cells and uricase sensitized cancer cells to 5-FU through uricase-uric acid-UMP synthase axis, which provided a potential strategy to improve the efficacy of 5-FU-based chemotherapy for human cancers.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Humanos , Neoplasias Hepáticas/metabolismo , Complexos Multienzimáticos , Orotato Fosforribosiltransferase , Orotidina-5'-Fosfato Descarboxilase , Urato Oxidase/uso terapêutico , Ácido Úrico
15.
Anal Chim Acta ; 1208: 339843, 2022 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-35525593

RESUMO

The chemistry of the metal-organic frameworks (MOFs) coating may affect the biological functionality of the encapsulated biomacromolecules in harsh environment. Enzymes encapsulated in hydrophilic MAF-7 can retain high activity in harsh environment. We conducted this study to prepare a non-invasive wearable uircase@MAF-7-based electrochemical sensor that can achieve accurate and sensitive detection of UA levels in sweat by integrating a flexible microfluidic chip and wireless electronic readout device. The flexible microfluidic chip enabled an easy and effective collection of sweat samples. MAF-7 protected enzyme activity by encapsulating uricase. The uricase@MAF-7-based electrochemical sensor enabled the highly sensitive detection of UA in the concentration range of 2 µM-70 µM with a detection limit of as low as 0.34 µM. Additionally, we evaluated the utility of the sensor for monitoring UA levels in real sweat samples by means of a high purine dietary challenge. This personalized wearable sweat sensing device has a potential to be used for monitoring disease-related metabolites in daily life.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Dispositivos Eletrônicos Vestíveis , Suor/química , Urato Oxidase , Ácido Úrico/análise
16.
Gut Microbes ; 14(1): 2070391, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35491895

RESUMO

Hyperuricemia is the second most prevalent metabolic disease to human health after diabetes. Only a few clinical drugs are available, and most of them have serious side effects. The human body does not have urate oxidase, and uric acid is secreted via the kidney or the intestine. Reduction through kidney secretion is often the cause of hyperuricemia. We hypothesized that the intestine secretion could be enhanced when a recombinant urate-degrading bacterium was introduced into the gut. We engineered an Escherichia coli Nissle 1917 strain with a plasmid containing a gene cassette that encoded two proteins PucL and PucM for urate metabolism from Bacillus subtilis, the urate importer YgfU and catalase KatG from E. coli, and the bacterial hemoglobin Vhb from Vitreoscilla sp. The recombinant E. coli strain effectively degraded uric acid under hypoxic conditions. A new method to induce hyperuricemia in mice was developed by intravenously injecting uric acid. The engineered Escherichia coli strain significantly lowered the serum uric acid when introduced into the gut or directly injected into the blood vessel. The results support the use of urate-degrading bacteria in the gut to treat hyperuricemia. Direct injecting bacteria into blood vessels to treat metabolic diseases is proof of concept, and it has been tried to treat solid tumors.


Assuntos
Infecções por Escherichia coli , Microbioma Gastrointestinal , Hiperuricemia , Animais , Escherichia coli/genética , Escherichia coli/metabolismo , Hiperuricemia/tratamento farmacológico , Camundongos , Oxigênio , Urato Oxidase/genética , Urato Oxidase/uso terapêutico , Ácido Úrico/metabolismo , Ácido Úrico/uso terapêutico
17.
Biotechnol Bioeng ; 119(9): 2518-2528, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35488433

RESUMO

Allantoin is an important fine chemical that can be widely used in pharmaceutical, cosmetic and agricultural industries. Currently, allantoin is mainly produced by plant extraction or chemical synthesis. Due to the cost and environmental concerns, biosynthesis of allantoin from renewable feedstock is much more desirable. However, microbial production of allantoin from simple carbon sources has not yet been achieved so far. In this study, de novo biosynthesis of allantoin was achieved by constructing an artificial biosynthetic pathway. First, screening of efficient urate oxidases and xanthine dehydrogenases enabled allantoin production from hypoxanthine, a natural intermediate in purine metabolic pathway in Escherichia coli. Then, assemble of the entire pathway resulted in 13.9 mg/L allantoin from glucose in shake flask experiments. The titer was further improved to 639.8 mg/L by enhancing the supply of the precursor, redistribution of carbon flux, and reduction of acetate. Finally, scale-up production of allantoin was conducted in a 1-L fermentor under fed-batch culture conditions, which enabled the synthesis of 2360 mg/L allantoin, representing a 170-fold increase compared with the initial strain. This study not only demonstrates the potential for industrial production of allantoin, but also provides a bacterial platform for synthesis of other purines-derived high-value chemicals.


Assuntos
Alantoína , Escherichia coli , Alantoína/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Engenharia Metabólica/métodos , Redes e Vias Metabólicas , Urato Oxidase/genética , Urato Oxidase/metabolismo
18.
Br J Clin Pharmacol ; 88(9): 4163-4170, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35419830

RESUMO

AIMS: Glucose-6-phosphate dehydrogenase (G6PD) deficiency, the most common enzymopathy in humans, can cause acute haemolysis resulting from exposure to certain medications, chemicals, infections and fava beans. Rasburicase, used to manage elevated uric acid levels in the oncologic emergency of tumour lysis syndrome, is one such drug. The US Food and Drug Administration (FDA) recommends testing of G6PD status prior to rasburicase administration for patients at higher risk for G6PD deficiency. METHODS: We performed a retrospective chart review of all oncology patients for whom a semi-quantitative biochemical test for detecting G6PD deficiency was performed prior to rasburicase administration over a 2.5-year period, in a large academic metropolitan hospital. RESULTS: We identified 16 out of 260 tested individuals as G6PD-deficient (6.1%), including six females. On average, test results were electronically available to health care providers within 4 hours of sample collection, with most results available within 2-3 hours. Four G6PD-deficient patients developed elevated uric acid levels. Two of the G6PD-deficient patients were treated with rasburicase, and subsequently developed haemolysis, which was appropriately managed. CONCLUSION: In summary, by providing information about G6PD status with a rapid turnaround time, we have taken a significant step towards personalized medicine in our institution. In spite of the test implementation, two out of four G6PD-deficient patients, who were no longer candidates for rasburicase use, still received the drug, highlighting the need for improved provider education.


Assuntos
Deficiência de Glucosefosfato Desidrogenase , Urato Oxidase , Feminino , Deficiência de Glucosefosfato Desidrogenase/complicações , Deficiência de Glucosefosfato Desidrogenase/diagnóstico , Hemólise , Humanos , Estudos Retrospectivos , Centros de Atenção Terciária , Urato Oxidase/administração & dosagem , Urato Oxidase/efeitos adversos , Ácido Úrico
19.
Talanta ; 244: 123455, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35397324

RESUMO

The abnormal levels of uric acid (UA) in body fluids are associated with gout, type (II) diabetes, leukemia, Lesch-Nyhan syndrome, uremia, kidney damage, and cardiovascular diseases. Also, the presence of uricase (UOx) symbolizes genetic disorders and corresponding complications. Therefore, the detection of UA and UOx in the body fluids is significant for clinical diagnosis. 4-Cyano-4'-pentylbiphenyl (5CB, a nematic liquid crystal (LC)) was doped with octadecyl trimethylammonium bromide (OTAB, a cationic surfactant), which formed a self-assembled monolayer at the aqueous/5CB interface. The UOx-catalyzed oxidation of UA yielded H2O2, releasing the single-strand deoxyribonucleic acid (ssDNA) from the nanoceria/ssDNA complex. The interaction of the released ssDNA with OTAB disrupted the monolayer at the aqueous/5CB interface, which resulted in a dark to bright change when observed through a polarized optical microscope. The LC-based sensor allowed the detection of UA with a linear range of 0.01-10 µM and a limit of detection (LOD) of 0.001 µM. The UA detection was also performed in human urine samples and the results were comparable to that of a standard commercial colorimetric method. Similarly, the detection of UOx was performed, with a noted linear range of 20-140 µg/mL. The LOD was as low as 0.34 µg/mL. The detection of UOx was also demonstrated in human serum samples with excellent performance. This method provides a robust sensing platform for the detection of UA and UOx and has potential for applications in clinical analysis.


Assuntos
Técnicas Biossensoriais , Líquidos Corporais , Cristais Líquidos , Líquidos Corporais/química , DNA de Cadeia Simples , Humanos , Peróxido de Hidrogênio/química , Urato Oxidase/química , Urato Oxidase/metabolismo , Ácido Úrico , Água
20.
BioDrugs ; 36(2): 95-103, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35316517

RESUMO

Refractory, or uncontrolled, gout is a chronic, progressive, inflammatory arthropathy resulting from continued urate deposition after failed attempts to lower serum uric acid below the therapeutic threshold with oral urate-lowering therapies such as allopurinol and febuxostat. Recombinant uricase is increasingly being used to treat refractory gout; however, the immunogenicity of uricase-based therapies has limited the use of these biologic therapies. Antidrug antibodies against biologic therapies, including uricase and PEGylated uricase, can lead to loss of urate-lowering response, increased risk of infusion reactions, and subsequent treatment failure. However, co-therapy with an immunomodulator can attenuate antidrug antibody development, potentially increasing the likelihood of sustained urate lowering, therapy course completion, and successful treatment outcomes. This review summarizes evidence surrounding the use of immunomodulation as co-therapy with recombinant uricases.


Assuntos
Gota , Ácido Úrico , Alopurinol/uso terapêutico , Anticorpos/uso terapêutico , Gota/tratamento farmacológico , Supressores da Gota/efeitos adversos , Supressores da Gota/uso terapêutico , Humanos , Urato Oxidase/uso terapêutico , Ácido Úrico/uso terapêutico
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