Urinary Uric Acid Research Articles

Integration of 6-Thioguanine Functionalized Molybdenum-Copper Bimetallic Nanoclusters With Fluorescence Spectroscopy for the Sensitive Detection of Uric Acid in Biofluids.

In this paper, a single-step synthetic approach is presented for the development of bimetallic molybdenum-copper nanoclusters (Mo-CuNCs), shielded by a small molecule 6-thioguanine (6-TG). The Mo-CuNCs possessed a small size, high fluorescence, stable behavior, and good solubility in water. The 6-TG-Mo-CuNCs exhibit strong blue fluorescence emission at 410 nm after exciting at 330 nm as compared to its monometallic nanoclusters. Utilizing 6-TG-Mo-CuNCs superior biochemical stability, uric acid (UA) can be specifically detected as an oxidative stress biomarker using an inner filter effect mechanism. The probe demonstrated good sensing capability for detecting UA within the range of 0.09-5.00 μM and a detection limit of 0.237 μM. The method feasibility is further validated by quantifying UA in urine and plasma samples.

Investigation of the chemiluminescence behavior of Ti3C2 MXene quantum dots as a sensing platform for uric acid

The current study explores the application of Ti3C2 MXene quantum dots (MQDs) as a chemiluminescent (CL) probe to determine uric acid (UA) in biological samples. The MQDs sensor was synthesized using ultrasonic-assisted hydrothermal method and characterized through Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, energy dispersive X-ray analysis, high-resolution transmission electron microscopy, and X-ray diffraction. The presence of MQDs significantly enhances the ultra-weak Fe(II)–S2O82− CL system. Subsequently, quenching of the probe’s CL signal was observed in the presence of UA. Thus, the designed CL sensor offers an excellent analytical capability for determining UA in the 0.15–2.5 µM range, with a limit of detection of 0.093 µM. The method was effectively used to analyze UA in human serum and urine, yielding recovery rates between 94.4 % and 108.3 % with relative standard deviations (RSD) ranging from 1.9 % to 5.9 %.

Risk factors of renal function deterioration after radical nephroureterectomy for upper tract urothelial carcinoma.

To investigate the risk factors of renal function deterioration after radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC). A total of 153 patients with UTUC who underwent radical surgery at a high-volume center in China from January 2015 to December 2019 were included in this study. The renal function of all patients was evaluated during follow-up. Besides, these patients were grouped according to postoperative renal function. The risk factors of renal function deterioration included age, sex, body mass index (BMI), T stage, tumor location and size, lymph node invasion, lymph node dissection (LND), surgical margin, tumor histology, lymphovascular invasion (LVI), hypertension, diabetes, hematuria, blood transfusion, hydronephrosis on the affected side, urine specific gravity, creatinine, uric acid, and preoperative glomerular filtration rate (GFR) on the healthy and affected sides. The correlation between risk factors and inclusion indexes was analyzed using univariate and multivariate analyses. A total of 153 patients were enrolled in this study, and the follow-up continued for 14 (11, 24) months. Acute kidney injury (AKI) was diagnosed in 65 patients in the short-term follow-up after RNU, and renal function deterioration was diagnosed in 52 patients in the long-term follow-up after RNU. The univariate analysis of 65 patients with short-term AKI revealed that there were statistically significant differences in preoperative hydronephrosis, hypertension, urinary protein, tumor size, preoperative Hb, preoperative creatinine, blood transfusion, and preoperative GFR of the healthy kidney. The multivariate Logistic regression analysis results showed that preoperative creatinine, GFR of the healthy kidney, and blood transfusion were independent risk factors for AKI. Moreover, The multivariate Logistic regression analysis of 52 patients with long-term renal insufficiency after surgery indicated that there were statistically significant differences in preoperative hydronephrosis, tumor size, preoperative GFR of the healthy kidney, and postoperative AKI. For patients with UTUC, the preoperative creatinine level is high, blood transfusion was given during or after procedure and the GFR of the healthy kidney is low, it is easy to have AKI in the short term after operation. In addition, there was no hydronephrosis before operation, the tumor size was small, the GFR of the healthy kidney was low before operation, AKI occurred after operation, the renal function was easy to deteriorate for a long time after operation. The above risk factors may aggravate renal function deterioration of these patients after surgery, resulting in the loss of the opportunity to continue treatment.

A comparative study of postadrenalectomy hyperuricemia and renal impairment in patients with unilateral primary aldosteronism: does histopathology subtype matter?

BackgroundPrimary aldosteronism (PA), which is present in 5–18% of hypertensive patients, is a leading cause of secondary hypertension. Adrenalectomy is often recommended for patients with unilateral primary aldosteronism (uPA), yielding good long-term outcomes. PA patients without hyperuricemia and chronic renal failure before adrenalectomy were enrolled in this cohort study. Serum uric acid (SUA) and renal filtration were measured one year post-adrenalectomy. Their relationships with pathologic features, histopathological subtype (classical or nonclassical (HISTALDO consensus)), and vessel stiffness were explored. The aim of this cohort study is to evaluate the correlation between post-adrenalectomy serum uric acid (SUA) levels and estimated glomerular filtration rate (eGFR) with the pathologic features delineated by the HISTALDO consensus. Additionally, the study seeks to assess the impact of these biochemical markers on peripheral vessel stiffness and brachial-ankle pulse wave velocity (baPWV) at a one-year follow-up visit.MethodsThis prospective cohort study included patients (N = 100) diagnosed with uPA who underwent adrenalectomy from Jan 1, 2007 to Dec 31, 2022.ResultsAt follow-up, elevated SUA, hyperuricemia, and a > 25% eGFR decrease were significantly more common in the classical than the nonclassical group. The incidence of postoperative hyperuricemia, herein referred to as post-adrenalectomy hyperuricemia (PAHU), was 29% (29/100) overall, 34.8% (23/66) in the classical group and 17.6% (6/34) in the nonclassical group. The incidence of eGFR reduction > 25% was 33% (33/100), 43.9% (29/66), and 11.8% (4/34), respectively. baPWV decreased more in the classical group than the nonclassical group.ConclusionFor PA patients with PAHU and/or renal impairment, we suggest monitoring SUA, pH, urine uric acid, and urine crystals and performing a KUB study and peripheral vascular and renal sonography (on which pure uric acid stones in the KUB are radiolucent) to determine whether drug intervention is required for cases of asymptomatic PAHU, especially patients in male gender, classical histopathology, or renal impairment.

Microfluidic Wearable Electrochemical Sensor Based on MOF-Derived Hexagonal Rod-Shaped Porous Carbon for Sweat Metabolite and Electrolyte Analysis.

Wearable sensors enable the noninvasive continuous analysis of biofluid, which is of great importance for healthcare monitoring. In this work, a wearable sensor was seamlessly integrated with a microfluidic chip which was prepared by a three-dimensional printing technology for noninvasive and multiplexed analysis of metabolite and electrolytes in human sweat. The microfluidic chip could enable rapid sampling of sweat, which avoids the sweat evaporation and contamination. Using a Zn metal-organic framework as a sacrificial template, the hexagonal rod-shaped porous carbon nanorod (PCN) with high porosity, a large specific surface area, and excellent conductivity was synthesized and exhibited the robust electrocatalytic ability of uric acid (UA) oxidation. Therefore, the PCN-based sensor showed high sensitivity and good selectivity of UA with a wide linear range of 10-200 μM and a low detection limit of 4.13 μM. Meanwhile, the potentiometry-based ion-selective electrode was constructed for detection of pH and K+, respectively, with good sensitivity, selectivity, reproducibility, and stability. In addition, the testing under different bending states demonstrated that mechanical deformation had little effect on the electrochemical performance of the wearable sensors. Furthermore, we evaluated the utility of the wearable sensor for multiplexed real-time analysis of UA, pH, and K+ in sweat during aerobic exercise, and the effect of the amount of consumed purine-rich foods on uric acid metabolite levels in sweat and urine was further investigated. The relationship between urine UA and sweat UA was obtained. Overall, this wearable sensor enables multiple electrolyte and metabolite analysis in different noninvasive biofluids, suggesting its potential application in personalized disease prevention.

Annual change in eGFR in renal hypouricemia: a retrospective pilot study.

Extremely low uric acid (UA) levels or increased urinary UA (Uua) excretion might be risk factors for kidney disease in renal hypouricemia (RHU) patients, but their relationship with kidney dysfunction is unclear. This study investigated time-dependent changes in eGFR in RHU patients. This multicenter retrospective study assessed UA metabolism and changes in eGFR (median 5.5years) in 13 RHU patients. We then compared eGFR change in 7 of 13 RHU patients whose eGFR could be measured for 4years with those in normouricemic group (n = 31). In addition, 7 RHU patients were divided into two groups based on URAT1 gene mutations: homozygote and compound heterozygote mutations (Homo/Com group, n = 3), and wild-type and heterogeneous mutations (WT/Hetero group, n = 4). In 13 RHU patients, the median and mean serum UA (SUA) were 0.8 (0.4-2.5) and 1.1 ± 0.7mg/dL. The median and mean Uua were 44.3 (12.7-141.1) and 49.7 ± 36.2mg/dL. The median and mean urinary urate clearance (Cua/Ccr) were 46.8 (11.3-73.6) and 43.3 ± 19.7%. Over 4years, eGFR did not change in the RHU group but declined in the normouricemic group. Annual mean eGFR decline and change rate in the RHU group were the same as those in the normouricemic group (- 1.09 ± 1.11 vs. - 1.09 ± 1.92mL/min/1.73 m2/year, p = 0.996) (- 1.74 ± 1.96 vs. - 1.36 ± 2.10%, p = 0.664). And no significant difference was found in eGFR decline or change rate between Homo/Com and WT/Hetero groups (- 0.33 ± 1.03 vs. - 1.67 ± 0.85mL/min/1.73 m2/year, p = 0.116) (- 0.61 ± 1.62 vs. - 2.59 ± 1.91%, p = 0.210). RHU from URAT1 genetic mutation may not show eGFR decline over 4 consecutive years.

A Multi-Channel Urine Sensing Detection System Based on Creatinine, Uric Acid, and pH.

Urine analysis represents a crucial diagnostic technique employed in clinical laboratories. Creatinine and uric acid in urine are essential biomarkers in the human body and are widely utilized in clinical analysis. Research has demonstrated a correlation between the normal physiological concentrations of creatinine and uric acid in urine and an increased risk of hypertension, cardiovascular diseases, and kidney disease. Furthermore, the pH of urine indicates the body's metabolic processes and homeostatic balance. In this study, an integrated multi-channel electrochemical sensing system was developed, combining electrochemical analysis techniques, microelectronic design, and nanomaterials. The architecture of an intelligent medical detection system and the production of an interactive interface for smartphones were accomplished. Initially, multi-channel selective electrodes were designed for creatinine, uric acid, and pH detection. The detection range was 10 nM to 100 μM for creatinine, 100 μM to 500 μM for uric acid, and 4 to 9 for pH. Furthermore, interference experiments were also conducted to verify the specificity of the sensors. Subsequently, multi-channel double-sided sensing electrodes and function-integrated hardware were designed, with the standard equations of target analytes stored in the system's read-only memory. Moreover, a WeChat mini-program platform was developed for smartphone interaction, enabling off-body detection and real-time display of target analytes through smartphones. Finally, the aforementioned electrochemical detection electrodes were integrated with the smart sensing system and wirelessly interfaced with smartphones, allowing for intelligent real-time detection in primary healthcare and individual household settings.

Prevalence of urinary metabolic disorders and risk factors of kidney stones in Iranian children

Introduction: Nephrolithiasis and urolithiasis, characterized by the formation of calculi in the kidney and lower urinary tract, respectively, pose a significant health concern for millions of children worldwide, particularly in developing countries. Objectives: This research aims to explore the prevalence of abnormal concentrations of urinary solutes as potential risk factors for kidney stones in Iranian children under the age of 14 years. Patients and Methods: A cross-sectional investigation spanning from January 2021 to January 2022 targeted children diagnosed with nephrolithiasis or urolithiasis through renal sonography, who were subsequently referred to the nephrology outpatient department of our hospital or our private pediatric nephrology office. Laboratory assessments encompassed urine calcium, oxalate, citrate, uric acid, creatinine, and urine cystine. Demographic attributes, stone composition (when available), and urinary metabolic disorders were scrutinized. Data analysis involved SPSS version 24, utilizing descriptive statistics such as mean, standard deviation, and frequency, categorized by variable type. Chi-square tests were employed for statistical analysis, with a significance threshold set at P<0.05. Results: The study encompassed 486 children, with a mean age of 55.58 months and a male majority of 50.8%. Among those with kidney stones, 77.2% exhibited unilateral stones, while 22.8% presented with bilateral stones. Predominant urinary metabolic disorders included hypercalciuria (30.2%), hyperuricosuria (22.6%), and hyperoxaluria (20.6%). Notably, 25.7% of the children manifested a combination of multiple metabolic disorders. Significant variations in the prevalence of hyperuricosuria were observed across different age groups. Boys exhibited higher incidences of hypercalcemia and metabolic abnormalities compared to girls, though no statistically significant differences were noted in other disorders. Conclusion: In summary, our findings indicate the presence of abnormal urinary metabolic risk factors in over half of children diagnosed with kidney stones. Hypercalciuria was the more frequent risk factor following hyperuricosuria and hyperoxaluria, cystinuria with prevalence of 30.2%, 22.6%, 20.6%, and (2.1%) respectively.

Prospective study investigating the influence of nutritional intervention on biochemical profiles in patients with recurrent urolithiasis.

Urolithiasis, commonly known as kidney stones, is a condition significantly impacted by dietary habits. The objective of this study is to evaluate the impact of a tailored dietary plan on the crystalluria and biological parameters of patients with different types of kidney stones over a 3-month period. We conducted a prospective study of 3 months. The study involved patients with recurrent nephrolithiasis. Alongside the medical consultation, a comprehensive dietary survey was performed to assess the patients' nutritional habits. Urinary parameters, including volume, calcium, oxalate, uric acid, and power of hydrogen (pH), were evaluated both before and after the dietary intervention. 69 patients were involved. There were 17 patients diagnosed with cystine lithiasis, 33 with oxalocalcic lithiasis and 19 with uric lithiasis. After 3 months, only 32 patients revisited for follow-up. There were significant changes (p = 0.002 and 0.04) in urine crystalluria for cystinic and uric lithiasis. For the urinary oxalate variation, there was a significant decrease from T1 (before dietary intervention) to T2 (after dietary intervention), with levels dropping from 0.289 ± 0.10 umol/l to 0.215 ± 0.079 umol/l (p = 0.02).Regarding urinary calcium (calciuria), there was a trend toward a decrease from T1 to T2, although the change was not statistically significant, with levels decreasing from 2.42 ± 1.68 umol/l to 2.14 ± 1.62 umol/l (p = 0.1). Our research underscores the favorable effects of a tailored and well-balanced diet on both the crystalluria and biological parameters of individuals with recurrent lithiasis.

Lanthanide MOF-based luminescent sensor array for detection and identification of contaminants in water and biomarkers

In today's society, heavy metal ions and antibiotic contaminants have caused great harm to water systems and human health. In this study, six isostructural lanthanide metal-organic frameworks [Ln(H3imda)2(TPA)(H2O)2](Tb for CUST-881, Eu for CUST-882, Dy for CUST-883, Er for CUST-884, Nd for CUST-885, Sm for CUST-886) were constructed by selecting terephthalic acid (TPA) and 4,5-Imidazoledicarboxylic acid (H3imda) and lanthanide metal ions via solvethermal method. Among them, CUST-881 and CUST-882 can selectively detect Fe3+, Cr2O72−, CrO42, and ceftriaxone sodium (CRO) in water systems and uric acid in urine. CUST-881 shows very low detection limits for these five substances. Furthermore, Principal Component Analysis (PCA) was used to distinguish Fe3+, Cr2O72−, CrO42−, and CRO in water. To our knowledge, this is the first time that they have been able to be simultaneously distinguished. In addition, the possible sensing mechanism was studied through UV–visible spectroscopy, Infrared spectroscopy, and PXRD analysis. Furthermore, the probe also showed satisfactory repeatability and recovery when applied to UA samples that simulated urine. Based on the above results, lanthanide metal-organic frameworks have great potential for practical monitoring of contaminants in water environments.

Changes in 24-hour Urine Chemistry in Patients with Nephrolithiasis during Weight Loss with Glucagon-Like Peptide-1 Based Therapies

Background: Obesity is an independent risk factor for incident and recurrent nephrolithiasis. The impact of weight loss through glucagon-like peptide 1 (GLP-1) receptor agonists and dual GLP-1/ gastric inhibitory polypeptide receptor agonists (GLP-based therapies) on nephrolithiasis is not well-understood. This study examined the changes in 24-hour urine chemistry assessing for stone risk during weight loss through GLP-based therapies. Methods: This retrospective analysis identified adult stone formers followed at our academic institution’s weight wellness clinic between September 2015 and August 2023 and included patients with at least two 24-hour urine collections for stone risk assessment. 24-hour urine parameters before and during weight loss in patients on GLP-based therapies were compared. Results: Forty-four obese patients with nephrolithiasis experienced significant weight reduction (-6.6±7.3 kg, p<0.001) over a median 1.1 years of follow-up with GLP-based therapies. During this period, there was a significant decrease in 24-hour urine oxalate (40±16 to 32±11 mg/day, p=0.002), sulfate (21±10 to 17±9 mmol/day, p=0005), and ammonium (35±22 to 29±15 mEq/day, p=0.01). There were non-significant changes in urine calcium, citrate, uric acid, pH, phosphorus, sodium, potassium, magnesium, chloride, creatinine or total volume. Additionally, there was no statistical difference in urine supersaturation indices with respect to calcium oxalate, calcium phosphate and uric acid. Conclusion: Our results indicate that weight loss through GLP-based therapies is not associated with pro-lithogenic changes in 24-hour urine chemistry in patients with nephrolithiasis, unlike what happens with other weight loss modalities.

IoT-Based Smart Toilet System to Detect Bacteria and Amount of Uric Acid in Urine

IoT-Based Smart Toilet System to Detect Bacteria and Amount of Uric Acid in Urine

Snowflake-like Ce-BTC@MoS2 heterojunction for high-performance uric acid detection

The analysis of uric acid (UA) in urine is adopted as a standard method for diagnosing related diseases, which provides an effective way for non-invasive detection of UA. However, no portable instruments presently can take an effective detection of UA in urine due to their detection limit, the indicator mainly impacted by sensitive materials. Hence, it is crucial to design electrochemical biosensor electrode materials with high sensitivity and the wide linear region for the detection of UA in urine. This research critically reveals a snowflake-like complex by simply combining the cerium-based metal-organic framework (Ce-BTC) and MoS2. The excellent electrochemical performance of Ce-BTC@MoS2 origins from the strong interfacial electronic interactions between Ce-BTC and MoS2 heterojunction and abundant active sites for UA oxidation. The Ce-BTC@MoS2 exhibits sensitivity (300.29 μA mM−1cm−2) for UA much higher than that of pristine Ce-BTC (129.14 μA mM−1cm−2) as well as MoS2 (209.71 μA mM−1cm−2) in the linear region from 5 to 2500 μM. The outstanding selectivity, excellent stability and attractive repeatability of the UA sensor fabricated by Ce-BTC@MoS2 have been also demonstrated, on account of the unique heterojunction of the electrode material. Additionally, the extensive linear region (0.5–4.4 mM) for the Ce-BTC@MoS2 sensor will be employed to analyze the concentration of UA in urine which can be directly measured without being processed. The prepared urine UA detector combined with the commercial blood UA detector provides an important basis for the comprehensive UA detection and clinical diagnosis.

Simultaneous Detection of Biomarkers in Urine Using a Multicalibration Potentiometric Sensing Array Combined with a Portable Analyzer.

Domestic monitoring devices make real-time and long-term health monitoring possible, allowing people to track their health status regularly. Uric acid (UA), creatinine, and urea in urine are three important biomarkers for various diseases, especially kidney diseases. This work proposed a 10-channel potentiometric sensing array containing a UA electrode group, a creatinine electrode group, a urea electrode group, a pH electrode group, and one pair of reference channels, which could be connected with a portable potentiometric analyzer, realizing the simultaneous detection of UA, creatinine, urea, and pH in urine. The prepared Pt/carbon nanotubes (CNTs)-uricase, creatinine deiminase, Au@urease, and polyaniline were employed as the sensing materials, showing responses to four targets with high sensitivity and selectivity. To improve the accuracy of domestic monitoring, a calibration channel was integrated into each electrode group to calibrate the basic potential of the sensing channels, and the influences of pH and temperature on the responses were investigated through the pH electrode group and an external temperature probe to calibrate the slope and intercept. With the preset of the deduced calibration parameters and computational formula for the four targets in the analyzer in Lab Mode, the concentrations of UA, creatinine, and urea and the pH of the human urine samples were directly displayed on the screen of the analyzer in Practical Mode. The agreement of these results with those obtained from commercial kits and pH meters reveals the high potential of these methods for developing domestic devices to facilitate health monitoring.

DaiTongXiao improves gout nephropathy by inhibiting inflammatory response through the TLR4/MyD88/NF-κB pathway.

Introduction: Gouty nephropathy (GN) arises from factors like excessive purine intake, metabolic disorders or abnormal synthesis, and uric acid hypersaturation in the blood, leading to urate crystal deposition in kidney tissue. DaiTongXiao (DTX) is a remedy used by the Dai people of China. It shows efficacy in lowering uric acid levels and exhibits anti-inflammatory and kidney-protective properties. Methods: A GN rat model was induced using adenine and potassium oxonate. Following DTX administration, various parameters were assessed in urine, serum, and kidney tissue. Western blot analysis evaluated TLR4/MyD88/NF-κB signaling proteins, while immunofluorescence examined NF-κB nuclear expression. Results: DTX treatment improved kidney morphology, increased body weight, and kidney index and enhanced urinary levels of blood urea nitrogen (Bun), 24-h urinary protein, uric acid (UA), and allantoin in GN rats, reducing UA, Bun, creatinine (Cre), cystatin C (CysC), serum amyloid A (SAA), α1-microglobulin (MG), and β2-MG in serum analysis. Renal tissue assessments showed decreased xanthine oxidase (XOD), hydroxyproline (Hyp), α-smooth muscle actin (α-SMA), and collage type Ⅳ (COL-Ⅳ). Kidney damage severity was notably reduced. DTX lowered serum inflammatory factors like interleukin (IL) -18, tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), transforming growth factor-β1 (TGF-β1), and IL-1β in the rat serum, reducing chemokine monocyte chemoattractant protein-1 (MCP-1) and adhesion factor vascular cell adhesion molecule-1(VCAM-1). Western blotting demonstrated the downregulation of TLR4/MyD88/NF-κB pathway proteins, and immunofluorescence revealed reduced NF-κB expression in renal tissue. Discussion: DTX exhibits significant anti-GN effects by modulating TLR4/MyD88/ NF-κB pathway protein expression, reducing inflammatory factor release, and inhibiting GN progression.

تحديد قياس الفولتامتري لحمض اليوريك في عينات الادرار الخاصة بأمراض الكلى المزمنة على قطب الزئبق

A voltammetric method has been described that is characterized by speed and high accuracy, and at the same time it is considered a sensitive and fast method compared to traditional methods for determining uric acid in urine. The method was determined that relies on the use of a mercury electrode as the basic substrate for the working electrode through the use of two different techniques at the same time for the purpose of uric acid determination. Uric acid based on uric acid reduction wave. In the presence of acetate buffer solution with a pH of 7.0, the optimal conditions that affect the method were studied, such as the pH, equilibrium time, and volume of the reducing agent. The size of the model through the sequence of addition of samples against the reference electrode (Ag/AgCl) in the presence of (KCl) with a concentration of (3) molar at a clear reduction wave at a voltage of (-0.6) volts and gave results with regular linear relationships for all the methods used and they were applied and compared. By traditional methods of measurement using Spectrophotometric.

The pathogenic mechanism of monosodium urate crystal-induced kidney injury in a rat model.

(MSU) crystals usually in the kidney tubules especially collecting ducts in the medulla. Previous animal models have not fully reproduced the impact of MSU on kidneys under non-hyperuricemic conditions. In the group treated with MSU, the upper pole of the rat kidney was injected intrarenally with 50 mg/kg of MSU, while the lower pole was injected with an equivalent volume of PBS solution. The body weight and kidney mass of the rats were observed and counted. H&E staining was used to observe the pathological damage of the kidney and to count the number of inflammatory cells. Masoon staining was used to observe the interstitial fibrosis in the kidneys of the rat model. Flow cytometric analysis was used for counting inflammatory cells in rats. ElISA was used to measure the concentration of serum and urine uric acid, creatinine and urea nitrogen in rats. At the MSU injection site, a significantly higher infiltration of inflammatory cells and a substantial increase in the area of interstitial fibrosis compared to the control group and the site of PBS injection were observed. The serum creatinine level was significantly increased in the MSU group. However, there were no significant differences in the rats' general conditions or blood inflammatory cell counts when compared to the control group. The injection of urate crystals into the kidney compromised renal function, caused local pathological damage, and increased inflammatory cell infiltration and interstitial fibrosis. Intrarenal injection of MSU crystals may result in urate nephropathy. The method of intrarenal injection did not induce surgical infection or systemic inflammatory response.

Ameliorative action of "daitongxiao" against hyperuricemia includes the "uric acid transporter group".

This study aimed to investigate the potential mechanisms involved in the therapeutic effects of daitongxiao (DTX) on hyperuricemia (HUA). DTX was administered to two animal models of HUA via gavage feeding: HUA quail model (a uricotelic animal with urate oxidase deficiency), treated continuously for 35 days post-HUA induction, and HUA rats (an animal with active urate oxidase), treated continuously for 28days post-HUA induction. HUA was induced in quail by administering a solution of sterile dry yeast powder via gavage feeding, while in rats, it was induced by intragastric gavage feeding of a solution of adenine and ethambutol hydrochloride. DTX improved overall health; increased bodyweight; reduced renal index, serum urate levels, serum xanthine oxidase activity, blood urea nitrogen, and creatinine; and enhanced urinary and fecal uric acid (UA) excretion in these two animal models. The results of hematoxylin and eosin and hexamine silver staining of kidney sections revealed that DTX significantly mitigated HUA-induced renal structural damage and inflammatory response. The results of quantitative real-time polymerase chain reaction, Western blotting, and immunofluorescence analyses revealed that DTX downregulated the renal expression levels of glucose transporter 9 (GLUT9) and upregulated the renal expression levels of organic anion transporters (OAT1 and OAT3) in both HUA models. Thus, the findings of this study suggest that DTX suppresses the progression of HUA by modulating the expression of the UA transporter group members.

Association of urinary excretion rates of uric acid with biomarkers of kidney injury in patients with advanced chronic kidney disease.

The potential influence of hyperuricemia on the genesis and progression of chronic kidney disease (CKD) remains controversial. In general, the correlation between blood levels of uric acid (UA) and the rate of progression of CKD is considered to be modest, if any, and the results of relevant trials oriented to disclose the effect of urate-lowering therapies on this outcome have been disappointing. Urinary excretion rates of UA could reflect more accurately the potential consequences of urate-related kidney injury. Using a cross-sectional design, we investigated the correlation between different estimators of the rates of urinary excretion of UA (total 24-hour excretion, mean urinary concentration, renal clearance and fractional excretion)(main study variables), on one side, and urinary levels of selected biomarkers of kidney injury and CKD progression (DKK3, KIM1, NGAL, interleukin 1b and MCP)(main outcome variables), in 120 patients with advanced CKD (mean glomerular filtration rate 21.5 mL/minute). We took into consideration essential demographic, clinical and analytic variables with a potential confounding effect on the explored correlations (control variables). Spearman's rho correlation and nonlinear generalized additive regression models (GAM) with p-splines smoothers were used for statistical analysis. Multivariate analysis disclosed independent correlations between urinary UA concentrations, clearances and fractional excretion rates (but not plasma UA or total 24-hour excretion rates of UA), on one side, and the scrutinized markers. These correlations were more consistent for DKK3 and NGAL than for the other biomarkers. Glomerular filtration rate, proteinuria and treatment with statins or RAA axis antagonists were other independent correlates of the main outcome variables. Our results support the hypothesis that urinary excretion rates of UA may represent a more accurate marker of UA-related kidney injury than plasma levels of this metabolite, in patients with advanced stages of CKD. Further, longitudinal studies will be necessary, to disclose the clinical significance of these findings.

FLAVONOIDS FOR ANTI-HYPERURICEMIA: A LITERATURE REVIEW

Background: Hyperuricemia is a condition on the level of uric acid in the blood increases, it is more than 6.0 mg/dL in women and more than 7.0 mg/dL in men and is currently a public health problem because of its increasing prevalence. Hyperuricemia is believed to have contributed to an increased risk of mortality and morbidity associated with various diseases such as metabolic syndrome, kidney disease, cardiovascular disease, etc. Flavonoids in plants can be used to help treat hyperuricemia due to it is believed to have low side effects. Objective: The aim of this article was to review the effect of flavonoids on plants as anti-hyperuricemia. Design: The design used in preparing this manuscript is an integrative review by reviewing articles on the impact of flavonoids as anti-hyperuricemia. Data Sources: Sources of information were obtained from research articles from 2004-2023 which were accessed through PubMed, Scopus, Sciendirect, SpringerLink, and Google Scholar. Review Methods: In the process of selecting articles to ensure the quality of the articles used in preparing this article, the authors used the PRISMA method. Results: In this article, 15 in vivo studies related to the effect of plants containing flavonoids (kaemferol, luteolin, apigenin, rutin quercetin, morin, butein, vitexin, etc.) on reducing uric acid levels by various mechanisms from previous studies. Conclusion: Based on several studies reported that flavonoids have an effect on lowering uric acid levels by inhibiting xanthine oxidase (XO) activity, affecting the expression of uric acid transporters in the kidneys which contribute to the increase of excretion of uric acid in urine.