Serum urate is associated with an increased risk of inflammatory bowel disease: A bidirectional Mendelian randomization study

BACKGROUND Previous studies have indicated bidirectional associations between urate levels and inflammatory bowel disease(IBD),including ulcerative colitis(UC)and Crohn’s disease(CD).However,it remains unclear whether the observations are causal because of confounding factors.AIM To investigate the causal associations between urate levels and IBD using bidirec-tional Mendelian randomization(MR).METHODS Independent genetic variants for urate levels and IBD were selected as instru-mental variables from published genome-wide association studies(GWASs).Summary statistics for instrument-outcome associations were retrieved from three separate databases for IBD(the UK Biobank,the FinnGen database and a large GWAS meta-analysis)and one for urate levels(a large GWAS meta-analysis).MR analyses included the inverse-variance-weighted method,weighted-median estimator,MR-Egger and sensitivity analyses(MR-PRESSO).A meta-analysis was also conducted to merge the data from separate outcome databases using a fixed-effects model.RESULTS Genetically higher serum urate levels were strongly associated with an increased risk of UC[odds ratio(OR):1.95,95%confidence interval(CI):1.86-2.05]after outlier correction,and the ORs(95%CIs)for IBD and CD were 0.94(95%CI:0.86-1.03)and 0.91(95%CI:0.80-1.04),respectively.Animal studies have confirmed the positive association between urate levels and UC.Moreover,genetically predicted IBD was inversely related to urate levels(OR:0.97,95%CI:0.94-0.99).However,no association was observed between genetically influenced UC or CD and urate levels.CONCLUSION Urate levels might be risk factors for UC,whereas genetically predicted IBD was inversely associated with urate levels.These findings provide essential new insight for treating and preventing IBD.

Highly specific characterization and discrimination of monosodium urate crystals in gouty arthritis based on aggregation-induced emission luminogens

Existing technologies used to detect monosodium urate(MSU)crystals for gout diagnosis are not ideal due to their low sensitivity and complexity of operation.The purpose of this study was to explore whether aggregation-induced emission luminogens(AIEgens)can be used for highly specific imaging of MSU crystals to assist in the diagnosis of gout.First,we developed a series of luminogens(i.e.,tetraphenyl ethylene(TPE)-NH_(2),TPE-2NH_(2),TPE-4NH_(2),TPE-COOH,TPE-2COOH,TPE-4COOH,and TPE-Ketoalkyne),each of which was then evenly mixed with MSU crystals.Next,optimal fluorescence imaging of each of the luminogens was characterized by a confocal laser scanning microscope(CLSM).This approach was used for imaging standard samples of MSU,hydroxyapatite(HAP)crystals,and mixed samples with 1:1 mass ratio of MSU/HAP.We also imaged samples from mouse models of acute gouty arthritis,HAP deposition disease,and comorbidities of interest.Subsequently,CLSM imaging results were compared with those of compensated polarized light microscopy,and we assessed the biosafety of TPE-Ketoalkyne in the RAW264.7 cell line.Finally,CLSM time series and three-dimensional imaging were performed on MSU crystal samples from human gouty synovial fluid and tophi.As a promising candidate for MSU crystal labeling,TPE-Ketoalkyne was found to detect MSU crystals accurately and rapidly in standard samples,animal samples,and human samples,and could precisely distinguish gout from HAP deposition disease.This work demonstrates that TPE-Ketoalkyne is suitable for highly specific and timely imaging of MSU crystals in gouty arthritis and may facilitate future research on MSU crystal-related diseases.

Determining the role for uric acid in non-alcoholic steatohepatitis development and the utility of urate metabolites in diagnosis:An opinion review

There has long been a recognised association between non-alcoholic fatty liver disease(NAFLD)and the composite aspects of the metabolic syndrome.Part of this association highlighted the supposed co-existence of elevated uric acid levels in those with NAFLD.There is interest in exploitation of this as a putative diagnostic and prognostic biomarker in NAFLD.Given the increased economic and health burden associated with the NAFLD epidemic,improved methods of population-based,minimally-invasive methods and biomarkers are clearly highly sought and necessary.In this opinion review we review the proposed role of uric acid in the pathogenesis of NAFLD and its potential utilisation in the diagnosis and monitoring of the disease process.

Chicory (Cichorium intybus L.) inhibits renal reabsorption by regulating expression of urate transporters in fructose-induced hyperuricemia

Objective:Hyperuricemia is an excess of urate in blood.The kidneys play important parts in urate excretion,which involves handling reabsorption and secretion.A series of urate transporters is responsible for this process:urate transporter (URAT)1,glucose transporter (GLUT)9,organic anion transporter (OAT)1 and OAT3.Excessive fructose intake may result in increased serum urate levels.Chicory (Cichorium intybus L.) has been used as an edible vegetable and traditional Chinese medicine.Studies have shown that chicory is a promising anti-hyperuricemia agent and we explored the mechanism of its uricosuric effect via a renal pathway.Methods:Hyperuricemia was induced in rats by administration of 10% fructose.The uricosuric effect was evaluated by determining the serum urate level.Renal excretory function was detected by the clearance rate of creatinine,clearance rate of uric acid and histology.The location and expression of URAT1,GLUT9,OAT1 and OAT3 their mRNA expression in kidneys were analyzed.Results:Chicory decreased serum levels of urate and creatinine significantly,and promoted the clearance of creatinine and urate,as well as improving renal pathologic changes due to hyperuricemia.Chicory inhibited expression of URAT1 and GLUT9 markedly in a dosedependent manner,but showed no influence on expression of OAT1 or OAT3.Conclusion:Chicory might be a promising anti-hyperuricemia agent.It can promote renal excretion of urate by inhibiting urate reabsorption,which may be related to downregulation of mRNA and protein expression of URAT1 and GLUT9.

Hearing loss due to urate deposition in the middle ear:A case report and literature review

Gout is the most common cause of monoarthritis in men occurring classically in the great toe and the knee.Extra-articular gout manifestations are rare.Only a few cases of head and neck urate crystals deposits have been described in the literature.Precipitations in the middle ear cause conductive hearing loss with common otoscopic anomalies and difficult imaging diagnosis.We report a case of a healthy 58-years-old man with a middle ear urate deposit causing a progressive hearing loss as the very first symptom of gout.The nature of the deposit was unsure on computer tomography(CT)due to atypical density.The final diagnosis was revealed after surgical procedure and histologic examination.A review of the literature is also presented.Seven cases of middle ear urate deposit as the first symptom of gout were found and compared.Progressive conductive hearing loss in middle-aged patients with abnormal otoscopy and middle ear atypical density mass on CT scan must lead to a minimal surgical procedure with a histologic examination to exclude urate crystals deposits.

Therapeutic Mechanism of Santeng Dingtong Recipe (三藤定痛方) on Monosodium Urate Crystal-Induced Rabbit Arthritis

Objective: To study the therapeutic mechanism of Santeng Dingtong recipe (STDT) on monosodium urate crystal (MSU) induced rabbit arthritis Methods: Forty-two rabbits were randomly divided into six groups, 7 in each group. Group 1 received 0.9% saline 2. 5 ml/kg per day by gastrogavage (ig) for 10 days; Group 2, 3 and 4 received STDT 0.125 g/kg, 1.0 g/kg and 8.0 g/kg per day respectively by ig for 10 days; Group 5 received colchicine 4. 5 mg/kg per day by ig for 4 days; and Group 6 was untreated. MSU crystals 10 mg /500ul containing polymyxin B 10 u/ml was injected into the knee joints of Group 1-5 to make rabbit arthritis models. Leukocytes in synovial lavage fluids was then counted and differentiated; pathological injury of synovial membranes was observed under HE staining; interleukin-1 beta (IL-1B), tumor necrosis factor alpha (TNFa) and leukotriene B4 (LTB4) content in synovial lavage fluids were determined by ELISA. Results: MSU caused a rapid leukocyte infiltration and increased production of IL-1B, TNFa and LTB4 2 hrs after intra-articular injection. STDT inhibited neutrophil infiltration in synovial fluids dose-dependently, protected the synovial membrane against pathological injury and reduced the production of IL-1B, TNFa and LTB4; while colchicine did not decrease the level of TNFa, but significantly inhibited neutrophil infiltration in synovial fluid and reduced the production of IL-11B and LTB4. Conclusion: STDT exerts an anti-inflammatory effect in rabbit model of acute MSU arthritis, its mechanism being probably due to the decrease of XL-1B, TNFa and LTB4 synthesis.

Successful prevention of tumor lysis syndrome using recombinant urate oxidase in patient with metastasic and bulky prostate rhabdomyosarcoma

Tumor lysis syndrome (TLS) is a life-threatening oncological emergency that frequently occurs in patients with hematological malignancies. It is becoming more common in patients with solid tumors because of advances in molecular targeted therapies. Recombinant urate oxidase (rUO) is effective at preventing and treating hyperuricemia, but clinicians who treat adult patients with solid tumors are generally not aware of this. In addition, the treatment guidelines for TLS do not include indications for rUO treatment for chemosensitive sarcoma. We report an adolescent case of metastatic rhabdomyosarcoma (RMS), in which clinical TLS was successfully prevented using rUO. A 16-year-old Japanese male suffered from urinary retention and bone pain and was diagnosed with prostate RMS combined with multiple bone metastases and bone marrow involvement. He was judged to be at high risk of clinical TLS because his prostate tumor was bulky and he displayed laboratory TLS. rUO was administered during chemotherapy. Soon after the initiation of chemotherapy, his disseminated intravascular coagulation (DIC) got worse, and his lactate dehydrogenase (LDH) level was elevated due to tumor lysis. However, his serum uric acid levels remained low, and he was prevented from falling into acute renal failure. The planned regimen was successfully completed without life-threatening complications, and the patient achieved a complete response after 2 courses of chemotherapy. The international TLS consensus panel developed recommendations for TLS prophylaxis, but did not define the TLS risk classification of RMS. We recommend that RMS should be treated like neuroblastoma because it grows rapidly and is highly chemosensitive. Our patient was considered to be indicated for rUO because he displayed urinary retention, DIC, and laboratory TLS before chemotherapy. These features might be useful as indications for rUO therapy, which can safely support chemotherapy.

Urate Transporter 1 Protein Levels and Localization in Type 2 Diabetic and Non-Diabetic Zucker Rat Kidneys

Objective: Persons with type 2 diabetes have increased incidence of hyperuricemia and gout. The hypothesis that Urate transporter 1 (URAT1) levels are increased in type 2 diabetic Zucker rats and this is responsible for elevation of uric acid was tested. Methods: Male 12-week-old obese Zucker rats were compared to non-diabetic lean counterparts. Plasma glucose, uric acid and creatinine were measured. URAT1 protein levels in the renal cortex and medulla were determined by Western blot. Immunohistochemistry was used to determine the location of URAT1 inrenal tubules. Results: Plasma glucose and uric acid levels were higher in the diabetic rats. There was no difference in plasma createnine. URAT1 antibody-positive bands of 27, 31, 50, 62 and 70 kDa were observed in cortex. A similar pattern was observed in medulla with addition of a 44 kDa band. No differences were observed in URAT1 proteins in the cortex between obese and lean rats. In the medulla, expression of the 44 and 50 kDa proteins was higher in lean rats. Expression of 27, 50, 62 kDa URAT1 proteins in the cortex was higher than in the medulla, while expression of the 70 kDa URAT1 was higher in medulla than in cortex. Localization of URAT1 did not differ between groups and included tubules in both cortex and medulla. Conclusions: In male Zucker rats, URAT1 protein expression was observed in both kidney cortex and medulla. Uric acid elevation in the obese group was associated with decreases in the 44 and 50 kDa URAT1 proteins in renal medulla.

Galangin probably ameliorates hyperuricemia by inhibiting urate acid transport 1 (URAT1): Homology modeling and mechanism exploration

Urate acid transporter 1(URAT1)is the main transporter of uric acid reabsorption,which closely related to the pathogenesis of hyperuricemia.Screening URAT1 inhibitors and studying their possible metabolic processes is a hot spot in the development of uric acid-lowering drugs.Studies have shown that many food-borne plant polyphenols have uric acid lowering activity with non-toxic side eff ects,and can be used to improve and alleviate hyperuricemia.In this study,we take galangin(GAL)as an example to explore the mechanism of plant polyphenols aff ecting hyperuricemia by inhibiting URAT1.Homology modeling was used to construct a three-dimensional model of URAT1 protein,and the structure was optimized.Ramachandran diagram was used to verify the rationality of model protein structure.A known URAT1 inhibitor,benzbromarone(BBR),was used to dock with URAT1 to determine the docking site and show the key amino acids.GAL and model protein were docked by molecular docking method to analyze their interaction.Meanwhile,comparing the interaction of BBR and GAL with the key amino acids of model proteins,the binding of GAL was more stable,suggesting that GAL could aff ects hyperuricemia by inhibiting URAT1.This paper aims to provide theoretical guidance for the development of new functional food ingredients for lowering uric acid.

Development of a radiomics model to discriminate ammonium urate stones from uric acid stones in vivo:A remedy for the diagnostic pitfall of dual-energy computed tomography

Background:Dual-energy computed tomography(DECT)is purported to accurately distinguish uric acid stones from non-uric acid stones.However,whether DECT can accurately discriminate ammonium urate stones from uric acid stones remains unknown.Therefore,we aimed to explore whether they can be accurately identified by DECT and to develop a radiomics model to assist in distinguishing them.Methods:This research included two steps.For the first purpose to evaluate the accuracy of DECT in the diagnosis of uric acid stones,178 urolithiasis patients who underwent preoperative DECT between September 2016 and December 2019 were enrolled.For model construction,93,40,and 109 eligible urolithiasis patients treated between February 2013 and October 2022 were assigned to the training,internal validation,and external validation sets,respectively.Radiomics features were extracted from non-contrast CT images,and the least absolute shrinkage and selection operator(LASSO)algorithm was used to develop a radiomics signature.Then,a radiomics model incorporating the radiomics signature and clinical predictors was constructed.The performance of the model(discrimination,calibration,and clinical usefulness)was evaluated.Results:When patients with ammonium urate stones were included in the analysis,the accuracy of DECT in the diagnosis of uric acid stones was significantly decreased.Sixty-two percent of ammonium urate stones were mistakenly diagnosed as uric acid stones by DECT.A radiomics model incorporating the radiomics signature,urine pH value,and urine white blood cell count was constructed.The model achieved good calibration and discrimination{area under the receiver operating characteristic curve(AUC;95%confidence interval[CI]),0.944(0.899-0.989)},which was internally and externally validated with AUCs of 0.895(95%CI,0.796-0.995)and 0.870(95%CI,0.769-0.972),respectively.Decision curve analysis revealed the clinical usefulness of the model.Conclusions:DECT cannot accurately differentiate ammonium urate stones from uric acid stones.Our proposed radiomics model can serve as a complementary diagnostic tool for distinguishing them in vivo.

三味小方靶向URAT1有效成分分子对接研究

目的:以URAT1(尿酸转运蛋白1)为靶点,利用分子对接,筛选出三味小方中抑制URAT1的有效成分。方法:用AlphaFold2.1对URAT1进行建模,利用ledock软件将土茯苓、威灵仙、萆薢三味中药的组分与URAT1进行对接,并与药物苯溴马隆进行比较,筛选出活性较好的组分。结果:三味中药中有多种组分能够与URAT1活性口袋结合良好,形成多个氢键,有的还形成了π-π键。其中土茯苓苷B、恩比宁等22种组分对接打分值优于苯溴马隆。结论:三味小方中含有土茯苓苷B、恩比宁等22种分子对接结果优于苯溴马隆的组分。该药方能够抑制URAT1,降低尿酸浓度。三味中药中,土茯苓包含有效成分最多。

玉米须总黄酮抗大鼠高尿酸血症及肾脏保护作用

目的:探讨玉米须总黄酮(TFCS)抗大鼠高尿酸血症(HUA)及肾脏保护的价值。方法:将60只SD大鼠随机分成正常对照组,模型组,别嘌呤醇组和TFCS低、中、高剂量组,每组10只。除正常对照组外,其余各组给予250 mg/(kg·d)乙胺丁醇和100 mg/(kg·d)腺嘌呤的混悬液灌胃14 d,构建大鼠HUA模型。造模后别嘌呤醇组给予50 mg/(kg·d)别嘌呤醇,TFCS低、中、高剂量组分别给予0.5、1.0、2.0 mg/(kg·d)TFCS灌胃14 d。观察并记录大鼠的一般状态和体重;检测大鼠血清中尿酸(UA)、肌酐(Cr)、尿素氮(BUN)、黄嘌呤氧化酶(XOD)水平及尿液中UA水平;HE染色观察肾组织病理形态变化;免疫组化法检测大鼠肾组织尿酸转运体1(URAT1)蛋白的表达;qRT-PCR法检测大鼠肾组织葡萄糖转运体9(GLUT9)mRNA的表达。结果:与正常对照组比较,模型组大鼠精神状态萎靡、排尿增多;血清UA、Cr、BUN、XOD水平升高,尿液UA水平降低(P<0.05);肾小管上皮边界模糊,细胞肿胀变性,肾间质炎性细胞浸润;肾组织URAT1蛋白和GLUT9 mRNA表达水平升高(P<0.05)。与模型组比较,别嘌呤醇组和TFCS低、中、高剂量组大鼠精神状态及排尿情况好转;血清UA、Cr、BUN、XOD水平降低,尿液UA水平升高(P<0.05);肾组织损伤减轻,URAT1蛋白和GLUT9 mRNA表达水平降低(P<0.05)。结论:TFCS可有效降低HUA大鼠UA水平,并对肾脏有一定保护作用,其作用机制可能与抑制UA合成关键酶活性及调节UA转运蛋白表达有关。

Monosodium urate crystals trigger Nrf2- and heme oxygenase-1-dependent inflammation in THP-1 cells

Gouty arthritis is an inflammatory disease that is caused by an accumulation of monosodium urate （MSU） crystals in the joints. MSU is capable of activating the nucleotide-binding oligomerization domain-like receptor pyrin domain containing 3 （NLRP3） inflammasome, leading to interleukin-lβ （IL-lβ） secretion. Reactive oxygen species （ROS） are major mediators of the NLRP3/IL-lβ interaction. Although nuclear factor E2-related factor 2 （Nrf2） is recognized as a transcription factor that is involved in the response to oxidative stress, the effect of MSU on Nrf2 and on Nrf2-mediated antioxidant enzymes remains unclear. The treatment of THP-1 monocytes using phorbol 12-myristate 13-acetate （PMA） was shown to initiate inflammatory responses. Here, we showed that THP-1 cells, following treatment with MSU crystals, significantly increased IL-1β release, NLRP3 inflammasome activation and ROS production. MSU also promoted the nuclear translocation of Nrf2 and activated lysosomal destabilization. Moreover, the levels of heme oxygenase-1 （HO-1） in gene and protein expressions were upregulated by MSU. MSU-induced IL-lβ secretion and NLRP3 inflammasome activation were inhibited by the knockdown of Nrf2 and via the HO-1 inhibitor zinc （11） protoporphyrin IX （ZnPP）. In addition, HO-1 inhibition increased the level of superoxide anion production and the consumption of glutathione. These findings suggest that Nrf2 and HO-1 mediate redox homeostasis and interact with pro-inflammatory factors in MSU-challenged THP-1 cells, thereby providing new insight into how MSU-induced gouty inflammation is mediated by specific mechanisms that are involved in the Nrf2/Ho-1 antioxidant signaling pathway.

Antihyperuricemic effect of mangiferin aglycon derivative J99745 by inhibiting xanthine oxidase activity and urate transporter 1 expression in mice

A mangiferin aglycon derivative J99745 has been identified as a potent xanthine oxidase(XOD) inhibitor by previous in vitro study. This study aimed to evaluate the hypouricemic effects of J99745 in experimental hyperuricemia mice, and explore the underlying mechanisms. Mice were orally administered 600 mg/kg xanthine once daily for 7 days and intraperitoneally injected 250 mg/kg oxonic acid on the 7 th day to induce hyperuricemia. Meanwhile, J99745(3, 10, and 30 mg/kg), allopurinol(20 mg/kg) or benzbromarone(20 mg/kg) were orally administered to mice for 7 days. On the 7 th day,uric acid and creatinine in serum and urine, blood urea nitrogen(BUN), malondialdehyde(MDA) content and XOD activities in serum and liver were determined. Morphological changes in kidney were observed using hematoxylin and eosin(H&E) staining. Hepatic XOD, renal urate transporter 1(URAT1), glucose transporter type 9(GLUT9), organic anion transporter 1(OAT1) and ATP-binding cassette transporter G2(ABCG2) were detected by Western blot and real time polymerase chain reaction(PCR). The results showed that J99745 at doses of 10 and 30 mg/kg significantly reduced serum urate, and enhanced fractional excretion of uric acid(FEUA). H&E staining confirmed that J99745 provided greater nephroprotective effects than allopurinol and benzbromarone. Moreover, serum and hepatic XOD activities and renal URAT1 expression declined in J99745-treated hyperuricemia mice. In consistence with the ability to inhibit XOD, J99745 lowered serum MDA content in hyperuricemia mice. Our resultssuggest that J99745 exerts urate-lowering effect by inhibiting XOD activity and URAT1 expression, thus representing a promising candidate as an anti-hyperuricemia agent.

Anti-inflammatory effects of traditional mixed extract of medicinal herbs(MEMH)on monosodium urate crystal-induced gouty arthritis

Korean oriental medicine prescription is widely used for the treatment of gouty diseases. In the present study, we investigated anti-inflammatory effects of modified Korean herbal formulation, mixed extract of medicinal herbs(MEMH), and its modulatory effects on inflammatory mediators associated with gouty arthritis. Both in vitro and in vivo studies were carried out to assess the anti-inflammatory efficacy of MEMH on monosodium urate(MSU) crystals-induced gouty inflammation. MSU crystals stimulated human chondrosarcoma cell line, SW1353, and human primary chondrocytes were treated with MEMH in vitro. The expression levels of pro-inflammatory mediators and metalloproteases were analyzed. The effect of MEMH on NFκB signaling pathway in SW1353 cells was examined. Effect of MEMH on the mR NA expression level of pro-inflammatory mediators and chemotactic factor from human monocytic cell line, THP-1, was also analyzed. The probable role of MEMH in the differentiation process of osteoblast like cells, SaO S-2, after MSU treatment was also observed. To investigate the effects of MEMH in vivo, MSU crystals-induced ankle arthritic model was established. Histopathological changes in affected joints and plasma levels of pro-inflammatory mediators(IL-1β and TNFα) were recorded. MEMH inhibited NFκB signaling pathway and COX-2 protein expression in chondrocytes. MSU-induced mR NA expressions of pro-inflammatory mediators and chemotactic cytokines were suppressed by MEMH. In MSU crystals-induced ankle arthritic mouse model, administration of MEMH relieved inflammatory symptoms and decreased the plasma levels of IL-1β and TNFα. The results indicated that MEMH can effectively inhibit the expression of inflammatory mediators in gouty arthritis, demonstrating its potential for treating gouty arthritis.

Suppression of monosodium urate crystal-induced inflammation by inhibiting TGF-β-activated kinase 1-dependent signaling:role of the ubiquitin proteasome system

Monosodium urate(MSU)crystals activate inflammatory pathways that overlap with interleukin-1β(IL-1β)signaling.However,the post-translational mechanisms involved and the role of signaling proteins in this activation are unknown.In the present study,we investigated the intracellular signaling mechanisms involved in MSU-induced activation of THP-1 macrophages and human nondiseased synovial fibroblasts(NLSFs)and the in vivo efficacy of an inhibitor of tumor grovArth factor-β(TGF-β)-activated kinase 1(TAK1),5Z-7-oxozeaenoI,in MSU-induced paw inflammation in C57BL76 mice.THP-1 macrophage activation with MSU crystals(25-200 ng/ml)resulted in the rapid and sustained phosphorylation of interleukin-1 receptor-activated kinase 1(IRAK1 Thr^(209))and TAK1(Thr^(184/187))and their association with the E3 ubiquitin ligase TRAF6.At the cellular level,MSU inhibited the deubiquitinases A20 and UCHL2 and increased 20s proteasomal activity,leading to a global decrease in K^(63)-linked ubiquitination and increase in K^(48)-linked ubiquitination in THP-1 macrophages.While MSU did not stimulate cytokine produaion in NLSFs,it significantly amplified IL-1β-induced IL-6,IL-8,and ENA-78/CXCL5 production.Docking studies and MD simulations followed by TAK1 in vitro kinase assays revealed that uric acid molecules are capable of arresting TAK1 in an active-state conformation,resulting in sustained TAK1 kinase activation.Importantly,MSU-induced proinflammatory cytokine production was completely inhibited by 5Z-7-oxozeaenol but not IRAK1/4 or TRAF6 inhibitors.Administration of 5Z-7-oxozeaenol(5 or 15 mg/kg;orally)significantly inhibited MSU-induced paw inflammation in C57BL/6 mice.Our study identifies a novel post-translational mechanism of TAK1 activation by MSU and suggests the therapeutic potential of TAK1 in regulating MSU-induced Inflammation.

Generation of mouse anti-human urate anion exchanger antibody by genetic immunization and its identification

Background Human urate anion exchanger (hURAT1) as a major urate transporter expressed on renal tubular epithelial cells regulates blood urate level by reabsorbing uric acid. Antibody is an important tool to study hURAT1. This study aimed, by genetic immunization, to produce mouse anti-hURAT1 polyclonal antibody with high throughput and high specificity and to detect the location of hURAT1 in human kidney.Methods Human renal total RNA was isolated and the entire cDNA of hURAT1 was amplified by RT-PCR. The sequence of intracellular high antigenicity fragment (A280 to R349) was chosen by prediction software of protein antigenicity, and its cDNA was amplified from cDNA of hURAT1, and then cloned into pBQAP-TT vector to construct recombinant plasmid pBQAP-TT-hURAT1-210 for genetic immunization. Mice were inoculated with this recombinant plasmid and two other adjuvant plasmids, pCMVi-GMCSF and pCMVi-Flt3L, which helped to enhance the antibody’s generation. After four weeks, the mice were sacrificed to obtain the anti-hURAT1 antibody from serum. The antibody was identified by western blot analysis and immunohistochemistry. At the same time, rabbit anti-hURAT1 antibody was produced by protein immunization. The specificity and efficiency between the rabbit and mouse anti-hURAT1 antibody were compared by western blot analysis and immunohistochemistry. Results The entire cDNA of hURAT1 and cDNA of its intracellular high immunogenic fragment were amplified successfully. Recombinant plasmid pBQAP-TT-hURAT1-210 for genetic immunization was confirmed by restriction digestion and sequencing. Both!the mouse anti-hURAT1 antibody and rabbit anti-hURAT1 antibody recognized 58kD hURAT1 and 64kD glycosylated hURAT1 protein bands in western blot. Immunohistochemically, hURAT1 was located at the brush border membrane of renal proximal tubular cells. In addition, the throughput and specificity of the mouse anti-hURAT1 antibody were higher than those of the rabbit anti-hURAT1 antibody.Conclusion Genetic immunization can generate anti-hURAT1 polyclonal antibody of high throughput and specificity.

3D-QSAR Analysis of Naphthyltriazole(Lesinurad) Analogs as Potent Inhibitors of Urate Transporter 1

To obtain useful information for identifying inhibitors of urate transporter 1(URAT1), three-dimensional quantitative structure-activity relationship(3 D-QSAR) analysis was conducted for a series of lesinurad analogs via Topomer comparative molecular field analysis(CoMFA). A 3 D-QSAR model was established using a training set of 51 compounds and externally validated with a test set of 17 compounds. The Topomer CoMFA model obtained(q^2 = 0.976, r2 = 0.990) was robust and satisfactory. Subsequently, seven compounds with significant URAT1 inhibitory activity were designed according to the contour maps produced by the Topomer CoMFA model.

卫星物联网系统的新型多址接入技术

面向传播时延大、需要服务更大规模用户数的卫星物联网场景,首先分析IoT NTN在技术方案方面的不足,进而提出非协调的随机接入和非正交多址传输(Uncoordinated Random Access and NOMA Transmission,URAT)新型多址接入解决方案。非协调指终端从随机接入到多址传输的过程中不需要专门的网络协调信令;非正交多址传输指所有终端在接入和传输过程中共享基站的时频资源实现非正交多址传输;URAT还实现了多址接入和NOMA传输的融合。理论分析和数值仿真结果表明,所提方案能够降低多址接入时延,提高系统效率,增加可以服务的终端数量,将是面向6G卫星物联网场景的潜在解决方案。

长时间持续运动对男青年血尿酸的影响

尿酸(urate)系嘌呤核苷酸的代谢终产物。血尿酸浓度的变化可以反映体内核酸的分解代谢情况。本文的研究目的在于探索男青年进行长时间持续运动前后的血尿酸变化,了解运动对核酸分解代谢的影响。