齿孔酸对高尿酸血症黄嘌呤氧化酶活性的影响

采用紫外分光光度法检测齿孔酸在体外对黄嘌呤氧化酶的作用,并进行动力学研究探讨其作用机制;采用酵母联合氧嗪酸钾诱导高尿酸血症小鼠模型,观察齿孔酸对高尿酸血症小鼠血清尿酸水平、血清黄嘌呤氧化酶活性、肝脏黄嘌呤氧化酶活性及血糖血脂的影响。研究发现,齿孔酸体在外能抑制黄嘌呤氧化酶活性,降低高尿酸血症小鼠血清尿酸水平、血清黄嘌呤氧化酶活性、肝脏黄嘌呤氧化酶活性,同时明显降低空腹血糖、总胆固醇、甘油三酯、低密度脂蛋白胆固醇水平,升高高密度脂蛋白胆固醇水平,提高口服糖耐受量。结果表明,齿孔酸是黄嘌呤氧化酶竞争性抑制剂,还能缓解高尿酸血症小鼠糖脂代谢紊乱,对高尿酸血症及痛风的防治具有潜在意义。     

蕨菜乙醇提取物降尿酸作用机理及肾保护作用研究北大核心CSCD

为研究蕨菜乙醇提取物降尿酸作用机理及其肾保护作用,将蕨菜乙醇提取物灌胃模型小鼠1周,于给药第3 d,氧嗪酸钾灌胃复制高尿酸血症小鼠模型,检测血清尿酸水平、血及肝脏黄嘌呤氧化酶活性,探讨其治疗高尿酸血症作用机理;蕨菜乙醇提取物灌胃模型小鼠1周,检测血Cr与BNU、肾组织NO与ET水平、肾组织形态学,考察其肾保护作用。结果发现蕨菜乙醇提取物可显著降低小鼠血清尿酸水平,对小鼠血及肝脏黄嘌呤氧化酶活性无显著影响,显著降低血Cr、血BNU、肾组织ET水平,升高肾组织NO水平,肾组织形态学正常。结果表明蕨菜乙醇提取物具有降尿酸及肾保护作用,其降尿酸作用机制不在影响黄嘌呤氧化酶活性,确切的作用机制还有待于进一步研究。     

蕨菜乙醇提取物降尿酸作用机理及肾保护作用研究

为研究蕨菜乙醇提取物降尿酸作用机理及其肾保护作用,将蕨菜乙醇提取物灌胃模型小鼠1周,于给药第3 d,氧嗪酸钾灌胃复制高尿酸血症小鼠模型,检测血清尿酸水平、血及肝脏黄嘌呤氧化酶活性,探讨其治疗高尿酸血症作用机理;蕨菜乙醇提取物灌胃模型小鼠1周,检测血Cr与BNU、肾组织NO与ET水平、肾组织形态学,考察其肾保护作用。结果发现蕨菜乙醇提取物可显著降低小鼠血清尿酸水平,对小鼠血及肝脏黄嘌呤氧化酶活性无显著影响,显著降低血Cr、血BNU、肾组织ET水平,升高肾组织NO水平,肾组织形态学正常。结果表明蕨菜乙醇提取物具有降尿酸及肾保护作用,其降尿酸作用机制不在影响黄嘌呤氧化酶活性,确切的作用机制还有待于进一步研究。     

L-阿拉伯糖对尿酸的调节作用

该文研究了L-阿拉伯糖对正常及高尿酸血症小鼠尿酸的调节作用。在正常小鼠、氧嗪酸钾和次黄嘌呤联合诱导的高尿酸血症小鼠以及氧嗪酸钾和尿酸联合诱导的高尿酸血症小鼠中,通过灌胃给予L-阿拉伯糖:收集尿液,测定尿酸排泄量;取血,测定血清中尿酸、总胆固醇、甘油三酯、血糖、肌酐、尿素氮等常规生化指标;处死小鼠后,取肝、肾、脾,称重,计算脏器指数;取小肠与肝脏,匀浆后测定黄嘌呤氧化酶活性。结果表明:L-阿拉伯糖对正常小鼠,可以增加尿酸排泄,但不能降低血尿酸水平;对氧嗪酸钾和次黄嘌呤联合诱导的高尿酸血症小鼠,对尿酸排泄没有影响,但能升高血尿酸水平;对氧嗪酸钾和尿酸联合诱导的高尿酸血症小鼠,对尿酸排泄及血尿酸水平都没有影响。该研究结果表明L-阿拉伯糖对正常血尿酸水平没有影响,但能升高特定条件下高尿酸血症小鼠的血尿酸水平。     

绞股蓝皂苷对高尿酸血症大鼠血尿酸的影响

高尿酸血症是近年来日益多发的代谢综合征。本研究探讨绞股蓝皂苷提取物对高尿酸血症大鼠血清尿酸的影响及作用方式。研究采用高尿酸血症大鼠动物模型,生化检测,代谢实验方法等,对摄入绞股蓝皂苷提取物的实验大鼠的血清尿酸水平,尿酸生成关键酶黄嘌呤氧化酶活性,24 h尿液酸碱度、尿酸浓度及尿酸排泄量等指标进行监测。结果发现,绞股蓝皂苷可以通过抑制尿酸生成,促进排泄,抑制机体的血尿酸水平升高,有益于改善高尿酸血症患者健康状况。     

海带褐藻多糖硫酸酯对腺嘌呤诱导的小鼠高尿酸血症的拮抗作用

本文探讨了海带褐藻多糖硫酸酯(fucoidan from Laminaria japonica,FL)对腺嘌呤诱导的小鼠高尿酸血症的拮抗作用。首先利用腺嘌呤灌胃法建立高尿酸血症动物模型,再以不同剂量(0.100、0.150、0.200 g/kg)的海带褐藻多糖硫酸酯治疗4周,最后对小鼠血清尿酸、肌酐、肝脏匀浆液中腺苷脱氨酶(ADA)和黄嘌呤氧化酶(XOD)的活性及小鼠肾脏组织病理学变化进行检测(HE染色)。结果表明,与空白组相比,腺嘌呤能极显著升高小鼠血清尿酸、肌酐水平、肝脏XOD及ADA活性(P0.01)。与模型组相比,海带褐藻多糖硫酸酯各剂量均能极显著降低小鼠血清尿酸、肌酐水平、肝脏XOD及ADA活性(P0.01)。光镜观察结果显示,与模型组相比,海带褐藻多糖硫酸酯治疗组小鼠的肾损伤有一定程度恢复。综上所述,海带褐藻多糖硫酸酯对腺嘌呤诱导的小鼠高尿酸血症有一定程度的缓解作用。     

番茄总皂苷对小鼠高尿酸血症的调节作用北大核心CSCD

为研究番茄总皂苷对尿酸的调节作用,该文以番茄水提物为试材,利用次黄嘌呤和氧嗪酸钾以及尿酸和氧嗪酸钾建立高尿酸模型小鼠,考察番茄总皂苷对正常小鼠及高尿酸血症小鼠尿酸排泄量、血尿酸、尿素氮、肌酐、黄嘌呤氧化酶以及脏器指数的影响。结果表明:番茄总皂苷不影响正常小鼠血尿酸水平,正常组及番茄低、中、高剂量组血尿酸值分别为(170.4±36.7)、(178.3±69.7)、(175.5±42.1)、(185.3±72.6)μmol·L^(-1);番茄总皂苷对次黄嘌呤和氧嗪酸钾联合诱导的高尿酸血症小鼠可以降低血尿酸水平,降低黄嘌呤氧化酶活性,正常组、模型组及番茄高剂量组血尿酸值分别为(140.4±36.7)、(378.3±69.7)、(278.3±62.6)μmol·L^(-1),正常组、模型组及番茄低、中、高剂量组黄嘌呤氧化酶值分别为(1.2±0.3)、(1.8±0.2)、(1.6±0.2)、(1.5±0.3)、(1.3±0.4)U·g^(-1) liver;对尿酸和氧嗪酸钾联合诱导的高尿酸血症小鼠,可降低血尿酸水平,降低黄嘌呤氧化酶活性,正常组、模型组及番茄高剂量组血尿酸值分别为(98.8±21.8)、(455.6±78.8)、(333.7±68.7)μmol·L^(-1),正常组、模型组及番茄高剂量组黄嘌呤氧化酶值分别为(2.1±0.3)、(2.5±0.2)、(2.3±0.2)U·g^(-1) liver。综上结果表明,番茄总皂苷不影响正常小鼠血尿酸水平,但能降低高尿酸模型小鼠的血尿酸水平,其机制可能与降低黄嘌呤氧化酶活性有关。     

三种互花米草天然化合物降尿酸作用研究

采用腹腔注射次黄嘌呤的方法构建高尿酸血症小鼠动物模型,选择苯溴马隆为阳性对照,选择互花米草精粉和去糖互花米草精粉作为拟阳性对照,研究异戊基奎尼酸(绿原酸)、苜蓿素和对香豆酸三种互花米草天然化合物的降尿酸作用。结果表明:对香豆酸可显著降低高尿酸血症小鼠的血清尿酸和血糖水平,其降尿酸和降血糖效果优于苯溴马隆。对香豆酸、绿原酸和苜蓿素能降低血清肌酐、尿素氮、总胆固醇和甘油三酯水平,同时还可以显著提高血清总蛋白浓度,具有一定的保护肾、降血脂作用。研究结果也表明,互花米草精粉具有更强的保肾护肝作用。     

芹菜素-钐配合物的合成及其抗小鼠高尿酸血症研究北大核心CSCD

秉承中药配位化学理论,以具有一定抗炎、抗痛风活性的芹菜素(AP)为配体,以稀土金属钐(Ⅲ)离子为配位中心,设计合成芹菜素-钐配合物(AP-Sm),以期提高抗高尿酸血症活性。采用紫外(UV)、红外(IR)、氢核磁共振(1H NMR)、电导法、差热-热重分析(TG-DTA)等技术对配合物的化学结构进行表征。考察配合物对酵母浸粉联合氧嗪酸钾诱导的高尿酸血症小鼠模型中尿酸、黄嘌呤氧化酶及超氧阴离子水平的影响。结果表明,芹菜素与钐(Ⅲ)离子配位生成了配合物,配合物组成式为:Sm(C_(15)H_9O_5)_3. 2H_2O。芹菜素A环的5-OH和C环的4位C=O与钐(Ⅲ)离子形成了配合物,且芹菜素与钐(Ⅲ)离子的配位比为3。抗高尿酸血症活性研究发现,芹菜素-钐配合物对高尿酸血症小鼠黄嘌呤氧化酶的抑制作用、清除超氧阴离子能力、降低血清尿酸水平及促进尿酸排泄能力均优于芹菜素。综上说明芹菜素与钐(Ⅲ)离子配位后,所得配合物抗高尿酸血症活性增强。     

石花菜醇提物对小鼠高尿酸血症的拮抗效应

本实验主要探讨了不同剂量(0.3 g/kg、0.6 g/kg、1.0 g/kg)的石花菜醇提物对小鼠高尿酸血症的拮抗效应。采用氧嗪酸钾盐对小鼠进行急性高尿酸血症造模,测定小鼠血清中尿酸(UA)、肌酐(Cr)和尿素氮(BUN)水平,以及小鼠肝脏匀浆液中黄嘌呤氧化酶(XOD)和腺苷脱氨酶(ADA)活性,HE染色观察其肾脏组织病理学变化。结果表明,与空白组相比,模型组小鼠血清中尿酸、肌酐和尿素氮水平显著升高(P0.01),同时,XOD活性也得到显著升高(P0.01),ADA活性升高(P0.05)。与模型组相比,阳性对照组与各药物治疗组均能显著降低小鼠血清中尿酸、肌酐和尿素氮水平(P0.01),同时,阳性对照组与各药物治疗组XOD活性均显著降低(P0.01),而两组ADA活性则均无统计学差异。光镜下与模型组相比,阳性对照组和药物治疗组小鼠肾脏的肾小球损伤一定程度上恢复正常。总体而言,石花菜醇提物对小鼠高尿酸血症具有很大程度的缓解作用,其机制与体内抑制尿酸生成和促进尿酸排泄有关。     

L-阿拉伯糖对尿酸的调节作用

转录因子是一类在生物生命活动过程中起到调控作用的重要因子,参与了各种信号转导和调控过程,可以直接或间接结合在顺式作用元件上,实现调控目标基因转录效率的抑制或增强,从而使植物在应对逆境胁迫下做出反应。 WRKY转录因子在大多数植物体内都有分布,是一类进化非常保守的转录因子家族,参与植物生长发育以及响应逆境胁迫的生理过程。众多研究表明,WRKY转录因子在植物中能够应答各种生物胁迫,如细菌、病毒和真菌等;多种非生物胁迫,包括高温、冷害、高光和高盐等;以及在各种植物激素,包括茉莉酸( JA)、水杨酸( SA)、脱落酸( ABA)和赤霉素( GA)等,在其信号传递途径中都起着重要作用。 WRKY转录因子家族蛋白至少含有一段60个氨基酸左右的高度保守序列,被称为WRKY结构域,其中WRKYGQK多肽序列是最为保守的,因此而得名。该转录因子的WRKY结构域能与目标基因启动子中的顺式作用元件W￣box( TTGAC序列)特异结合,从而调节目标基因的表达,其调控基因表达主要受病原菌、虫咬、机械损伤、外界胁迫压力和信号分子的诱导。该文介绍了植物WRKY转录因子在植物应对冷害、干旱、高盐等非生物胁迫与病菌、虫害等生物胁迫反应中的重要调控功能,并总结了WRKY转录因子在调控这些逆境胁迫反应过程中的主要生理机制。     

3,5,2',4'-Tetrahydroxychalcone, a new non-purine xanthine oxidase inhibitor

Xanthine oxidase is a key enzyme that catalyses hypoxanthine and xanthine to uric acid and the overproduction of uric acid will lead to hyperuricemia which is an important cause of gout. In the present study, three chalcone derivatives were synthesized and evaluated for inhibitory activity against xanthine oxidase in vitro. Of the compounds, only Compound 1, 3,5,2′,4′-tetrahydroxychalcone, exhibited a significant inhibitory activity on xanthine oxidase with an IC₅₀ value of 22.5 μM. Lineweaver–Burk transformation of the inhibition kinetics data demonstrated that it was a competitive inhibitor of xanthine oxidase and Ki value was 17.4 μM. In vivo, intragastric administration of Compound 1 was able to significantly reduce serum uric acid levels and inhibited hepatic xanthine oxidase activities of hyperuricemic mice in a dose-dependent manner. Acute toxicity study in mice showed that Compound 1 was very safe at a dose of up to 5 g/kg. These results suggest that Compound 1 is a novel competitive xanthine oxidase inhibitor and is worthy of further development.     

Synthesis and evaluation of hydroxychalcones as multifunctional non-purine xanthine oxidase inhibitors for the treatment of hyperuricemia

A series of hydroxychalcone derivatives have been designed, synthesized and evaluated for human xanthine oxidase (XO) inhibitory activity. Most of the tested compounds acted moderate XO inhibition with IC₅₀ values in the micromolar rang. Molecular docking and kinetic studies have been performed to explain the binding modes of XO with the selected compounds. In addition, in vitro antioxidant screening results indicated that some of the hydroxychalcones possessed good anti-free radical activities. Furthermore, the preferred compounds 16 and 18 were able to significantly inhibit hepatic xanthine oxidase activity and reduced serum uric acid level of hyperuricemic mice in vivo. In summary, compounds 16 and 18 with balanced activities of antioxidant, XO inhibition and serum uric acid reduction, which are promising candidates for the treatment of hyperuricemia and gout.     

Salusin-alpha and -beta expression in heart and aorta with and without metabolic syndrome

Metabolic syndrome (MetS) is a major health problem throughout the world. The role of salusins has not been investigated in heart and aortic tissues under MetS conditions. We examined the distribution of salusin alpha (sal-α) and salusin beta (sal-β) immunoreactivity in heart and aortic tissues and measured circulating salusin concentrations, glucose, insulin, triglycerides, free fatty acids, uric acid, and total cholesterol in Sprague-Dawley rats with and without MetS. Lipid, glucose, insulin and uric acid levels were determined using an autoanalyzer. Serum and tissue salusin levels were measured using ELISA. The expressions of salusins in the heart and aorta tissues were determined using immunohistochemical methods. Serum high density lipoprotein cholesterol (HDL-C), sal-α and sal-β concentrations were significantly lower in the MetS group than in the control group. Low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C), total cholesterol, glucose, uric acid and insulin concentrations were higher in the MetS group than in the control group. Sal-α and sal-β were synthesized locally in the fibroblasts and smooth muscle cells of the media of the aorta and in the muscle cells of the heart. Local synthesis of sal-α and sal-β was decreased with MetS. Our findings indicate that decreased serum concentrations of salusins and HDL-C and increased uric acid, glucose and triglyceride concentrations may be indicators of MetS and could play a role in the development of cardiovascular disease.     

铁观音茶水提物对小鼠高尿酸血症的缓解作用

近年来,高尿酸血症（hyperuricemia,HUA）在人群中频发,危害性强,并发症多。为了探究日常饮品--半发酵茶铁观音茶水对于缓解HUA是否具有辅助作用,以小鼠为实验对象,采用氧嗪酸钾和次黄嘌呤联合法构建小鼠高尿酸血症模型,21只模型鼠随机分为模型组、铁观音茶水提物组、阳性药物组,7只非模型鼠作为对照。做不同处理2周后,取小鼠血清及肾、肝、小肠。观察各器官病理变化,从细胞层面鉴定铁观音茶水提物对高尿酸血症小鼠各脏器的影响;测定与HUA相关度较高的生化指标：血清尿酸（uric acid,UA）浓度、肝黄嘌呤氧化酶（xanthine oxidase,XOD）活力,以明确造模是否成功以及判断铁观音茶水提物对HUA是否具有缓解作用;利用qRT-PCR检测尿酸合成和排泄相关基因的mRNA表达水平,并利用Western blot检测肝XOD蛋白的表达水平,以从分子层面明确铁观音茶水提物对HUA的影响。病理切片显示,相比于阳性药物组,铁观音茶水提物组小鼠的肾和肝损害程度较轻;生化指标测定结果显示,铁观音茶水提物可降低血清尿酸水平,并且抑制XOD活性;从分子层面可以看出,铁观音茶水提物显著升高了尿酸重吸收转运体尿酸转运蛋白1(uric acid transporter 1,URAT1)和有机阴离子转运蛋白3(organic anion transporter 3,OAT3)的mRNA表达水平（P<0.05）,显著降低了葡萄糖转运子9（glucose transporter 9,GLUT9）和有机阴离子转运蛋白1(organic anion transporter 1,OAT1)的表达水平（P<0.05）。虽然qRT-PCR和Western blot提示,XOD的mRNA和蛋白质的表达水平升高,但尿酸生成量却下降,推测可能是铁观音茶水提物中的某种成分使得无催化活性的XOD蛋白表达增加进而对XOD基因的转录表达造成一种正反馈。研究提示,铁观音茶水提物对小鼠高尿酸血症具有缓解作用,其缓解高尿酸血症的作用与抑制XOD活性、干预尿酸生成过程和刺激或抑制相关阴离子转运体mRNA的表达相关。     

Comprehensive analysis of mechanism underlying hypouricemic effect of glucosyl hesperidin

Hyperuricemia is caused by hepatic overproduction of uric acid and/or underexcretion of urate from the kidneys and small intestine. Although increased intake of citrus fruits, a fructose-rich food, is associated with increased risk of gout in humans, hesperidin, a flavonoid naturally present in citrus fruits, reportedly reduces serum uric acid (SUA) levels by inhibiting xanthine oxidase (XOD) activity in rats. However, the effects of hesperidin on renal and intestinal urate excretion were previously unknown. In this study, we used glucosyl hesperidin (GH), which has greater bioavailability than hesperidin, to clarify comprehensive mechanisms underlying the hypouricemic effects of hesperidin in vivo. GH dose-dependently decreased SUA levels in mice with hyperuricemia induced by potassium oxonate and a fructose-rich diet, and inhibited XOD activity in the liver. GH decreased renal urate excretion without changes in kidney URAT1, ABCG2 or GLUT9 expressions, suggesting that reducing uric acid pool size by inhibiting XOD decreased renal urate excretion. We also found that GH had no effect on intestinal urate excretion or protein expression of ABCG2. Therefore, we concluded that GH exhibits a hypouricemic effect by inhibiting XOD activity in the liver without increasing renal or intestinal urate excretion. Of note, this is the first study to elucidate the effect of a flavonoid on intestinal urate excretion using a mice model, whose findings should prove useful in future food science research in the area of urate metabolism. Taking these findings together, GH may be useful for preventing hyperuricemia, especially in people with the overproduction type.     

Identification of novel isocytosine derivatives as xanthine oxidase inhibitors from a set of virtual screening hits

In recent years, xanthine oxidase has emerged as an important target not only for gout but also for cardiovascular and metabolic disorders involving hyperuricemia. Contrary to popular belief, recent clinical trials with uricosurics have demonstrated that enhanced excretion of uric acid is, by itself, not adequate to treat hyperuricemia; simultaneous inhibition of production of uric acid by inhibition of xanthine oxidase is also important. Virtual screening of in-house synthetic library followed by in vitro and in vivo testing led to the identification of a novel scaffold for xanthine oxidase inhibition. In vitro activity results corroborated the results from molecular docking studies of the virtual screening hits. The isocytosine scaffold maintains key hydrogen bonding and pi-stacking interactions in the deep end of the xanthine-binding pocket, which anchors it in an appropriate pose to inhibit binding of xanthine and shows promise for further lead optimization using structure-based drug design approach.     

绝经后女性高尿酸血症患者性激素结合球蛋白与血尿酸的相关研究

目的：研究绝经后女性高尿酸血症患者血浆中性激素结合球蛋白（sexhormonebindingglobulin,SHBG）水平与血尿酸水平的相关性。方法：选取绝经后女性404例,其中高尿酸血症组204例,正常对照组200例,测量所有研究对象体重、身高、腰围、臀围、收缩压（SBP）、舒张压（DBP）,并计算体重指数（BMI）和腰臀比（WHR）,检测血尿酸（UA）、空腹血糖（FBG）、总胆固醇（TG）、甘油三酯（TC）低密度脂蛋白（LDL）、高密度脂蛋白（HDL）、雌激素（E2）、雄激素（T）、空腹胰岛素（INS）及SHBG,并计算胰岛素抵抗指数（Homa-IR）。结果：与绝经后女性尿酸正常者相比,高尿酸血症的患者UA,WHR,TC,FBG,INS,Homa-IR明显升高（P〈0．01）,DBP,WAIST和LDL升高（P〈0．05）,SHBG水平明显下降（P〈0．01）;SHBG与INs、uA、TG呈显著负相关（P〈0．05）,SHBG与E2呈显著正相关P〈0．01）。结论：绝经后女性中高尿酸血症患者的低血浆SHBG水平与高血尿酸水平显著相关,血浆SHBG水平下降与胰岛素抵抗可能高度相关,低sHBG可能作为绝经后女性患高尿酸血症的高危因素。     

Altered Serum Selenium and Uric Acid Levels and Dyslipidemia in Hemodialysis Patients Could be Associated with Enhanced Cardiovascular Risk

In the present study, the first objective was to follow up serum selenium (Se) concentrations in 117 hemodialysis patients (HPs) during a 2-year longitudinal study, relating concentrations to biochemical indexes (n?=?6; namely lipoprotein profile, uric acid, and total protein levels). It was also evaluated whether the disease is associated with an enhanced cardiovascular risk. A healthy control group (n?=?50) was also studied. Mean serum Se levels were significantly lower in HPs than in the controls (p?=?0.002); mean levels significantly increased from the first to third blood sampling (p?相似文献