Abstract
Importance
Hyperuricemia (HUA) is a major metabolic disorder in poultry, leading to gout and kidney damage, which affects farm productivity. Accordingly, understanding the pharmacodynamics (PD) and pharmacokinetics (PK) of uric acid-lowering drugs is essential for improving the treatment strategies in poultry.
Objective
This study examined the PD and PK characteristics of allopurinol and benzbromarone, two uric acid-lowering drugs, in a quail model of HUA.
Methods
A hyperuricemic quail model was established using a high-purine diet. Allopurinol and benzbromarone were administered orally. Blood samples were taken and analyzed for the drug concentrations using high-performance liquid chromatography. Pathological examinations were conducted to assess kidney damage.
Results
Both drugs lowered the serum uric acid levels. On the other hand, the allopurinol treatment exhibited lower urea and creatinine levels than benzbromarone, indicating potential advantages in reducing kidney damage. Consistent with these findings, the pathological examinations revealed more pronounced kidney damage in the benzbromarone-treated group than in the allopurinol group. PK analysis showed that allopurinol exhibited faster absorption and elimination kinetics than benzbromarone. Both drugs showed a wide distribution in various tissues, with allopurinol and its active metabolite displaying higher excretion levels.
Conclusions and Relevance
This paper reports the absorption, distribution, metabolism, and excretion processes of allopurinol and benzbromarone in a quail model of HUA. These findings help better understand the PK characteristics of these drugs and promote the use of high uric acid therapy in poultry. In addition, this quail model is a valuable tool for future research on HUA and drug interventions.
Keywords: Poultry, gout, therapy, kidney disease
INTRODUCTION
In poultry farming, an improper feed ratio, such as an excessive protein content, vitamin deficiency, or an imbalance in calcium-phosphorus ratios, can lead to the onset of hyperuricemia (HUA) and gout in poultry [1]. HUA is a risk factor for the development of gout and contributes to the progression of various metabolic disorders and cardiovascular complications [2,3]. Poultry gout, a major metabolic disease triggered by chronic HUA, is characterized by the deposition of monosodium urate crystals in the kidneys (renal gout), joints (articular gout), and soft tissues (visceral gout) [4]. Clinical manifestations include weight loss, joint swelling, and diarrhea [5]. Gout in chicks is associated with significant mortality, and outbreaks of poultry gout frequently result in breeding losses that adversely affect farm productivity [6]. This underscores the need to evaluate potential therapeutic agents for treating poultry gout, which is the focus of this study.
Benzbromarone and allopurinol are well-known treatments for HUA, each with distinct mechanisms of action. Allopurinol is a competitive xanthine oxidase inhibitor, reducing uric acid production by occupying the catalytic sites of the enzyme. This effect is achieved by allopurinol itself and its active metabolite, oxypurinol [7]. Allopurinol is an affordable and effective uric acid production inhibitor with notable advantages. On the other hand, it is often associated with more severe adverse reactions [8,9].
In contrast, benzbromarone functions primarily as a hypouricemic agent, with its glucose-lowering effects being secondary. The effects are achieved by inhibiting URAT1, the primary luminal uric acid transporter in the proximal tubules of the human kidney, enhancing uric acid excretion [10]. By inhibiting urate reabsorption, benzbromarone increases its elimination through urine. In vitro studies have shown that benzbromarone can reduce urate reabsorption by up to 93%.
HUA is not entirely understood, and the recognition of its harmful effects is limited. This research examined drug absorption, distribution, metabolism, and excretion (pharmacokinetic [PK]), as well as the pharmacodynamic characteristics in poultry, exploring their effectiveness in controlling HUA and helping to establish precise guidelines for poultry drug application. This study will provide foundational insights for optimizing poultry health management and treatment strategies in the future by systematically analyzing the metabolic processes and pharmacological responses to common drugs in poultry. In addition, the model has significant potential as a translational platform for human health. In the long term, this research establishes a reliable animal model for uric acid-lowering drug treatments, laying the foundation for future veterinary and human medical research and helping better understand the efficacy and safety of drugs for treating HUA and gout.
METHODS
Reagents and materials
Allopurinol tablets were obtained from Shanghai Pharmaceuticals Holding Co., Ltd. (China). Benzbromarone tablets were obtained from YiChang HEC ChangJiang Pharmaceutical Co., Ltd. (China). Carboxymethyl cellulose (CMC-Na) was purchased from Shanghai Shenguang Edible Chemicals Co., Ltd. (China). The molding agent yeast extract was acquired from OXOID Co., Ltd (UK) and mixed into the commercial feed formulation according to the 500 g/kg weight ratio. High-performance liquid chromatography (HPLC) grade methanol (MeOH) and acetonitrile (ACN) were procured from Anaqua Chemicals Supply (China). Analytical reagent grade formic acid, sodium hydroxide (NaOH), and hydrochloric acid (HCl) were purchased from Aladdin Chemistry Co., Ltd. (China) and XILONG Chemistry Co., Ltd. (China), respectively. Double-distilled water was prepared in the laboratory using a Milli-Q system (Millipore, USA). Assay kits for the aspartate aminotransferase (AST), blood uric acid, blood urea nitrogen (UREA), and creatinine (CREA) were supplied by Jinhua Qiangsheng Biological Technology Co., Ltd. (China). Male French quails, aged eight weeks and weighing 200–250 g, were obtained from West Anhui University (Certification No. WXXY 2022-0012).
We analyzed the specificity, stability, precision, and recovery rate of the HPLC detection conditions, with detailed results provided in Supplementary Materials (Supplementary Data 1 and 2, Supplementary Tables 1, 2, 3, 4, 5, Supplementary Fig. 1).
Experimental animals
The quails were housed in cages measuring 90 × 60 × 40 cm3 and maintained under standard laboratory conditions, including a temperature of 25°C ± 2°C, air humidity of 50%–55%, and a 12-h light-dark cycle. Before the experiments, the quails were acclimated to these conditions for one week and given access to water and food ad libitum. The study was also approved by the Ethics Committee on Animal Welfare of the Key Laboratory of Quality Evaluation and Improvement of Traditional Chinese Medicine, West Anhui University, Anhui Province (WXXY202209-2). All experimental procedures were conducted according to the National Institutes of Health Guide for the Care and Use of Laboratory Animals.
Induction of the hyperuricemic quail model
After the one-week acclimation, 104 male French quails were assigned randomly to one of four groups. The control group (CON, n = 10) was fed a standard commercial diet. The model group (MOD, n = 10) received a diet supplemented with yeast extract powder. The allopurinol-treated group (ALL, n = 42) received the same diet as the model group and was administered a 40 mg/kg allopurinol water solution orally. The benzbromarone-treated group (BEN, n = 42) also received the model group diet and was administered a 40 mg/kg benzbromarone water solution orally. HUA was induced in all groups, except for the control group, by administering an adenine solution at 40 mg/kg body weight for 12 weeks until the end of the study.
On the third week and the 86th day after the initial oral administration of yeast extract powder and adenine, approximately 1 mL blood samples were collected from all quails via the left jugular vein. The blood samples were collected in tubes without anticoagulants, and the resulting serum samples were obtained by centrifuging at 1,100×g for 10 min at 4°C. These serum samples were then analyzed for various blood biochemical indices, including uric acid, AST, UREA, and CREA. The uric acid content in the serum samples was measured to evaluate the efficacy of the hyperuricemic quail model.
Preparation of blank plasma and tissue sample
The control group quails were euthanized, and blood and tissue samples were collected to prepare blank plasma and tissue specimens. Approximately 900 μL of plasma or tissue sample was combined with 100 μL of standard working solution in a centrifuge tube and vortexed for 30 sec. Subsequently, 3 mL of methanol solution was added. The mixture was vortexed for another 30 sec and centrifuged at 1,100×g for 10 min at 4°C. This process facilitated analyte extraction and protein precipitation. The supernatant was transferred carefully to a new tube, and the solvent was removed by lyophilization to yield a dry residue. The residue was reconstituted with 1 mL of methanol: water solution (60:40, v/v), vortexed for 30 sec, and centrifuged at 1,100×g for 10 min at 4°C. The final supernatant was stored at −80°C until analysis.
Pharmacokinetic
PK study of plasma
After establishing the hyperuricemic quail model, the allopurinol-treated and benzbromarone-treated quails were divided into eight groups (n = 3). Before the experiment, all quails underwent an overnight fast with access to water only. Each quail received a single oral gavage dose of allopurinol at 40 mg/kg. Approximately 300 μL blood samples were collected from the right jugular vein at 0, 0.5, 1, 1.5, 3, 5, 8, and 12 h after administration. The collected blood samples were centrifuged at 1,100×g for 10 min at 4°C to obtain plasma, which was then treated with a methanol solution.
A 100 μL aliquot of plasma was mixed with 400 μL of methanol solution. The mixture was vortexed for 1 min and centrifuged at 1,100×g at 4°C for 10 min to extract the analytes and remove the endogenous protein materials. The resulting supernatant was transferred to another tube and lyophilized until dry. The residue was reconstituted with 100 μL of a methanol-water solution (60:40, v/v), vortexed for 1 min, and then centrifuged at 1,100×g for 10 min at 4°C. After vortex-mixing and filtration through a Millex-GN nylon filter, the sample was transferred to an autosampler vial. The processed plasma samples were analyzed by HPLC.
Tissue distribution
For the tissue distribution study, the quails treated with allopurinol were divided into two groups consisting of three quails each (n = 3). After an overnight fast, each quail received a single oral gavage dose of allopurinol at 40 mg/kg. Five or 12 h after oral allopurinol administration, the quails were euthanized, and tissues, including the heart, liver, spleen, lung, stomach, kidney, and intestine, were collected. The collected tissues were rinsed with ice-cold saline, gently blotted to remove the excess moisture, and weighed. Portions of the tissue samples were then homogenized in ice-cold saline at a weight/volume (w/v) ratio of 1:5 using a homogenizer. The homogenized tissue samples were then lyophilized for further analysis.
A liquid–liquid extraction method was used to enhance the recovery of allopurinol and benzbromarone from the tissue samples. In the benzbromarone-treated group, 500 μL of tissue homogenate was combined with 500 μL of the reference solution containing benzbromarone (60 μg/mL in methanol). The mixture was extracted with 1 mL of water-saturated butyl alcohol solution by vortexing for 30 sec, and the supernatant was collected carefully in a silicone container. This extraction process was repeated five times. In the allopurinol-treated group, 500 μL of tissue homogenate was mixed with 500 μL of a reference solution containing allopurinol (60 μg/mL in 0.4% NaOH solution), extracted with 1 mL of petroleum ether, and vortexed for 30 sec. The supernatant was collected, and the extraction was repeated twice. The tissue samples were prepared for HPLC analysis using a similar procedure to that used for plasma samples (as outlined above).
Metabolism studies
In the drug metabolism study, the allopurinol-treated group (n = 3) and the benzbromarone-treated group (n = 3) received a single oral dose of 40 mg/kg via gavage following an overnight fast. Fecal samples were collected at 0–5 h and 5–12 h post-administration. All fecal samples were dried at 50°C, weighed accurately, and ground to a fine powder. The analytes were extracted, and endogenous proteins were removed by homogenizing a 1 g sample of the powdered feces in ice-cold saline at a 1:5 (w/v) ratio. Subsequently, 200 μL of the homogenized fecal sample was mixed with 1 mL of methanol, vortexed for one minute, and centrifuged at 1,100×g for 10 min at 4°C. This process facilitated the extraction of analytes and the precipitation of endogenous proteins. The supernatant was transferred carefully to a new tube and lyophilized to obtain a dry residue.
The dried residue from the fecal samples was reconstituted by adding 200 μL of a methanol–water solution (60:40, v/v). The mixture was vortexed for 30 sec and centrifuged at 1,100×g for 10 min at 4°C. After centrifugation, the supernatant was filtered carefully through a Millex-GN nylon filter. The filtered sample was transferred to an autosampler vial for further analysis. The processed plasma samples were also analyzed by liquid chromatography/quadrupole time of flight mass spectrometry following a similar procedure.
Renal histopathological analysis
The kidneys of the quails were excised and fixed immediately in 4% polyoxymethylene for 24 h at room temperature. After fixation, the kidneys underwent standard histological processing and were embedded in paraffin. Five-micron-thick sections were prepared from each specimen using a rotary microtome. The sections were deparaffinized in xylene, rehydrated progressively through a series of ethanol solutions with decreasing concentrations and stained with hematoxylin and eosin. The stained sections were examined under a microscope.
Statistical analysis
The concentration–time profiles of allopurinol and benzbromarone were analyzed to calculate the PK parameters using the non-compartmental method in Phoenix WinNonlin software. The parameters included the peak time (Tmax), the elimination rate constant from the central compartment to the peripheral compartment (K01_HL), the elimination rate constant from the peripheral compartment to the central compartment (K10_HL), the area under the curve (AUC), maximum concentration (Cmax), and apparent volume of distribution (V_F). The data are expressed as mean ± SD. The differences between the two groups were evaluated statistically using a two-tailed Student’s t-test in IBM SPSS 24.0., with p values < 0.05 considered significant. Graphical representations were generated using Origin 2019b software.
RESULTS
Therapeutic efficacy of the single-dose allopurinol and benzbromarone administration on hyperuricemic quails
The HUA group served as symptom control, and the allopurinol-treated and benzbromarone-treated groups were used as treatment controls. The body weight was checked every 10 days. The body weight gain was similar in all groups throughout the experimental period, as shown in Fig. 1A (p > 0.05).
Fig. 1. (A) Body weights of quails. (B) Uric acid level in serum. (C) Glutamic oxalacetic transaminase level in serum. (D) Urea nitrogen level in serum. (E) Creatinine level in serum.
CON, the control group; MOD, the model group, ALL, the allopurinol-treated group, BEN, the benzbromarone-treated group.
*p < 0.05 vs. CON group; #p < 0.05 vs. MOD group.
Before modeling, venous blood samples were collected from the quails on days 20 and 86. Fig. 1B shows the changes in uric acid levels. Compared to that observed before modeling, the uric acid levels in all groups on day 20 were significantly higher than those in the control group (p < 0.05), indicating the successful establishment of HUA in quails. Furthermore, compared to the control group, the uric acid levels in the MOD group increased significantly from day 20 and remained elevated until day 86. In contrast, the uric acid levels in the ALL and BEN groups decreased gradually from days 20 to 86; the differences were statistically significant. These results showed that allopurinol and benzbromarone had a significant effect on reducing the serum uric acid levels.
In addition, after treatment with allopurinol or benzbromarone, the ALL and BEN groups showed significant reductions in the serum AST levels compared to the MOD group. Regarding renal function markers, the ALL group showed a decrease in the urea values compared to the MOD group, and the difference was significant (p < 0.05). By contrast, no significant difference was observed in the BEN group. Furthermore, the ALL and BEN groups exhibited significantly higher creatinine levels than the MOD group (p < 0.05). These results are shown in Fig. 1C, D, and E.
Effects of allopurinol and benzbromarone on the morphology and function of the kidney
In the blank group, the renal glomeruli and tubules showed a normal morphology, with no evidence of inflammatory cell infiltration and no significant pathological changes in the interstitium. The model group showed a disordered renal tubular arrangement, irregular tubular structure, and varying degrees of tubular dilation. The tubular walls appeared blurry, and necrotic cell clusters were deposited within some of the tubular lumens. The allopurinol-treated group showed morphological changes in the renal glomeruli, which were larger than in the blank group. Some tubular epithelial cells exhibited swelling, while vacuolar degeneration was less common. The benzbromarone-treated group showed a disordered renal tubular arrangement, varying degrees of tubular dilation, blurry tubular walls, homogenous reddish proteinaceous material, and deposits of necrotic cell clusters within some tubular lumens. Cell vacuolar degeneration was observed, and the renal glomeruli appeared enlarged with reduced cystic spaces. Fig. 2 provides details of the pathological sections.
Fig. 2. Representative histological image of quail kidney tissue stained with hematoxylin and eosin. (A) CON showing normal renal architecture. (B) Higher magnification of CON group illustrating intact glomerulus (arrow). (C) MOD demonstrating renal tissue damage and inflammatory infiltration (arrow). (D) Higher magnification of MOD group highlighting glomerular alterations (arrow). (E) ALL exhibiting partial morphological recovery (arrow). (F) Higher magnification of ALL group showing improved glomerular structure (arrow). (G) BEN presenting marked tissue recovery (arrow). (H) Higher magnification of BEN group revealing restored glomeruli and tubular structures (arrows). Scale bar: (A,C,E,G) = 200, (B,D,F,H) = 100 μm.
CON, the control group; MOD, the model group; ALL, the allopurinol-treated group; BEN, the benzbromarone-treated group.
Pharmacokinetics
Plasma level of allopurinol and benzbromarone
The plasma concentration–time profiles of allopurinol and benzbromarone were analyzed using a one-compartmental PK model after oral administration of a single 40 mg/kg dose in quails. Fig. 3 shows the resulting mean plasma concentration–time curves. Table 1 lists the pPK parameters estimated by fitting the plasma concentration profiles.
Fig. 3. Plasma concentration versus time profiles after oral administration (20 mg/kg) in quails (n = 3). (A) Benzbromarone-treated group. (B) Allopurinol-treated group.
Table 1. Pharmacokinetic parameters of benzbromarone and allopurinol after oral administration in quails (n = 3).
| Parameters | Estimate | SE | CV% | |
|---|---|---|---|---|
| BEN | ||||
| AUC, h × µg/mL | 220.94 | 24.8 | 11.18 | |
| K01_HL, h | 0.64 | 0.26 | 41.17 | |
| K01, 1/h | 1.07 | 0.44 | 40.99 | |
| K10_HL, h | 2.06 | 0.32 | 15.37 | |
| K10, 1/h | 0.34 | 0.05 | 15.35 | |
| Tmax, h | 1.56 | 0.31 | 19.66 | |
| Cmax, μg/mL | 44.01 | 5.56 | 12.59 | |
| V_F, mg/(μg/mL)/kg | 0.53 | 0.12 | 22.56 | |
| ALL | ||||
| AUC, h × µg/mL | 21.28 | 1.29 | 6.05 | |
| K01_HL, h | 0.23 | 0.06 | 27.93 | |
| K01, 1/h | 3.02 | 0.84 | 27.96 | |
| K10_HL, h | 0.40 | 0.05 | 11.51 | |
| K10, 1/h | 1.73 | 0.20 | 11.53 | |
| Tmax, h | 0.43 | 0.04 | 10.42 | |
| Cmax, μg/mL | 17.46 | 1.76 | 10.09 | |
| V_F, mg/(μg/mL)/kg | 1.08 | 0.13 | 11.68 | |
BEN, benzbromarone; AUC, area under the curve; K, elimination rate constant; K01_HL, the elimination rate constant from the central compartment to the peripheral compartment; Tmax, time to peak; K10_HL, the elimination rate constant from the peripheral compartment to the central compartment; Cmax, peak concentration; V_F, the apparent volume of distribution; ALL, allopurinol.
Benzbromarone achieved a peak plasma concentration (Cmax) of 44.01 ± 5.56 mg/L at approximately 1.56 ± 0.31 h and an area under the curve (AUC) of 220.94 ± 24.8 (h × µg/mL). The elimination rate constant from the central to peripheral compartments was 0.64 ± 0.26. The elimination rate constant from the peripheral to central compartments was 2.06 ± 0.32. These results suggest that allopurinol undergoes rapid absorption and elimination, showing a relatively short retention duration in the body.
Allopurinol showed a Cmax and AUC of 17.46 ± 1.76 mg/L at approximately 0.43 ± 0.04 h and 21.28 ± 1.29 (h × µg/mL), respectively. The elimination rate constant from the central to peripheral compartments was 0.23 ± 0.06. The elimination rate constant from the peripheral to central compartments was 0.4 ± 0.05. These findings suggest that benzbromarone undergoes rapid absorption and elimination.
Tissue distribution of allopurinol
After oral administration to quails, both drugs are distributed widely in various major tissues of the quail body. Fig. 4 and Supplementary Table 5 show the distribution of both drugs in the heart, liver, lung, kidney, intestine, stomach, and spleen at 5 h and 12 h after administration. Within the 0–5 h time range, allopurinol showed no significant difference in distribution among tissues except the spleen, and no significant change in the concentrations was observed in the liver and kidney from 5 to 12 h. In contrast, benzbromarone exhibits the highest concentration in the spleen within the 0–5 h range, and its concentration continues to increase in the liver and kidney from 5 to 12 h, suggesting a possible accumulation tendency in the liver and kidney within the measurement time.
Fig. 4. Bio-distribution of the two drugs in the hyperuricemia quails after a single allopurinol or benzbromarone oral gavage dose of 40 mg/kg.
*p < 0.05 vs. 5 h.
Excretion studies after the single-dose benzbromarone and allopurinol administration
Fig. 5 shows the excretion of the parent drugs and their corresponding metabolites in the feces of quails with the high uric acid model after oral administration of benzbromarone and allopurinol.
Fig. 5. Cumulative feces excretion ratios of the two drugs in the hyperuricemia quails after a single allopurinol or benzbromarone oral gavage dose of 40 mg/kg.
**p < 0.01, ##p < 0.01 vs. 0–5 h.
DISCUSSION
The lack of animal models suitable for urate metabolism is one of the main reasons for the limitation of HUA studies. Uric acid is the main product of purine metabolism, and most mammals, such as rats, mice, and rabbits, have uricase in their bodies. Uricase oxidizes uric acid into allantoin, which is easily soluble in water and thus facilitates excretion [11]. Evolutionary biology research has shown that humans and birds have mutations in the uricase gene that prevent the further oxidation of uric acid, making it the final product of purine metabolism [2,12]. As a result, the uric acid levels in humans and birds are higher than in other species [11,12,13]. Quails are a common bird species that have long been used as experimental animals because of their suitable body size and superior reproductive ability [14]. Although there is currently no standard model of HUA in quails, this study developed a quail HUA model suitable for a high-purine diet, which is closer to real-world research and provides a basis for studying HUA treatment in poultry.
The functional status of the kidneys is crucial for uric acid metabolism. Damage to the kidneys by drugs or other factors can increase the burden on the kidneys, leading to impaired uric acid excretion, reduced uric acid elimination, and elevated serum uric acid levels [15]. Based on these findings, both drugs had uric acid-lowering effects in the quail model of HUA. Nevertheless, allopurinol appeared to have a more favorable renal profile. Specifically, the allopurinol-treated group showed lower urea and creatinine levels than the benzbromarone-treated group, suggesting less renal impairment. A pathological examination revealed more severe kidney damage in the benzbromarone-treated group. These observations indicate that allopurinol may be the better option from a renal toxicity perspective. The lower kidney damage observed with the allopurinol treatment may confer a significant therapeutic advantage, particularly in patients or animals with underlying kidney concerns. Therefore, considering the efficacy in lowering uric acid and the potential renal safety, allopurinol has a more balanced therapeutic profile.
Furthermore, under the chromatographic conditions used in this experiment, the target compound and internal standard had a good peak shape, no stray peak interference, and the baseline was stable. This method has high specificity and sensitivity and can accurately determine the concentration of the two kinds of drugs in quail plasma. The absolute and relative recoveries were 89.9%–110.10% and 95%–105%, respectively. The lower limit of quantification was good and met the determination requirements. In addition, the stability was examined under three different conditions; all met the requirements. This method fulfilled the requirements of biological sample analysis and the standards for research and determination.
Research on the detailed PK of both drugs has been limited. This study conducted a PK investigation of benzbromarone and allopurinol using a quail model of HUA. Specifically, the Cmax, AUC, and elimination rate for allopurinol and benzbromarone in quails provided essential insights into the absorption, systemic exposure, and elimination of these drugs. These findings showed that allopurinol exhibited faster absorption and elimination compared to benzbromarone. Both drugs are distributed widely in various tissues, but the distribution difference of allopurinol in organs, such as the liver and kidneys, was not significant. This may be attributed primarily to rapid absorption and metabolism, resulting in the presence of its active metabolite oxypurinol. In addition, benzbromarone is metabolized primarily by CYP2C9, with its main metabolite being 6-hydroxybenzbromarone [16]. Quail excretes benzbromarone exclusively in the form of feces, suggesting that its elimination occurs predominantly through fecal excretion. Moreover, the excretion proportion of allopurinol and its active metabolite was higher than that of benzbromarone (Fig. 5) [17]. This may be related to the longer half-life of benzbromarone. The PK parameters of allopurinol in this study were similar to those reported by Day et al. [18], but this study provided a more comprehensive assessment of the PK parameters of allopurinol. These findings provide valuable insights into the treatment of HUA in quails and serve as a potential model for human health applications. A foundation for further research on the efficacy and safety of these drugs in humans was provided by establishing a PK profile for allopurinol and benzbromarone in quails.
In conclusion, this study developed a high uric acid model in quails, effectively simulating the PK behavior of uric acid-lowering drugs. This study provided valuable insights into their PK profiles by examining the absorption, distribution, metabolism, and excretion of allopurinol and benzbromarone. These findings lay the groundwork for future animal models in uric acid metabolism research and offer practical guidance for selecting the most suitable drugs in the clinical treatment of HUA and gout in poultry, aiming to optimize the therapeutic outcomes and minimize potential complications.
ACKNOWLEDGMENTS
We thank all the members of Anhui Provincial Key Laboratory for Enhancing and Evaluating the Quality of Chinese Medicine for their suggestions and helpful discussion in the preparation of this manuscript.
Footnotes
Funding: This research was supported by the Anhui Scientific Research and Innovation Team of Quality Evaluation and Improvement of Traditional Chinese Medicine under Grant 2022AH010090; the Project of Anhui Rural Revitalization of Traditional Chinese Medicine Industry Collaborative Technology Service Center under Grant GXXT-2022-079; the Provincial Level Nature Science Foundation of Anhui Education Department 2022AH051676; and West Anhui University High-Level Talent Research Start-up Funding under Grant 00701092394.
Conflict of Interest: The authors declare no conflicts of interest.
Data Availability Statement: The datasets used and/or analysed during the current study are available from the corresponding author upon reasonable request.
- Conceptualization: Zheng S.
- Data curation: Bu Y, Li S.
- Formal Analysis: Zheng S, Bu Y, Li S.
- Funding acquisition: Chen N.
- Investigation: Bu Y, Li S.
- Methodology: Zheng S, Bu Y, Li S.
- Project administration: Chen N.
- Resources: Zheng S.
- Software: Bu Y, Li S.
- Supervision: Chen N.
- Validation: Zheng S .
- Visualization: Bu Y, Li S.
- Writing - original draft: Zheng S.
- Writing - review & editing: Chen N.
SUPPLEMENTARY MATERIALS
Methods
Results
Calibration curves for allopurinol and benzbromarone in quail plasma and tissues
Precision and accuracy for the assay of allopurinol and benzbromarone in plasma and tissues (n = 5)
Stability of Allopurinol in quail plasma and tissue (n = 3)
Stability of benzbromarone in quail plasma and tissue (n = 3)
Typical chromatograms of quail plasma. (A) Chromatogram of blank plasma at 230 nm. (B) Chromatogram of blank plasma with benzbromarone at 230 nm. (C) Chromatogram of plasma samples from the benzbromarone-treated group at 10 min after drug administration. (D) Chromatogram of blank plasma with allopurinol at 230 nm. (E) Chromatogram of plasma samples from the allopurinol-treated group at 10 min after drug administration.
In vivo bio-distribution studies of allopurinol in quails at 5 and 12 h (μg/g, mean ± SD, n = 3).
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Associated Data
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Supplementary Materials
Methods
Results
Calibration curves for allopurinol and benzbromarone in quail plasma and tissues
Precision and accuracy for the assay of allopurinol and benzbromarone in plasma and tissues (n = 5)
Stability of Allopurinol in quail plasma and tissue (n = 3)
Stability of benzbromarone in quail plasma and tissue (n = 3)
Typical chromatograms of quail plasma. (A) Chromatogram of blank plasma at 230 nm. (B) Chromatogram of blank plasma with benzbromarone at 230 nm. (C) Chromatogram of plasma samples from the benzbromarone-treated group at 10 min after drug administration. (D) Chromatogram of blank plasma with allopurinol at 230 nm. (E) Chromatogram of plasma samples from the allopurinol-treated group at 10 min after drug administration.
In vivo bio-distribution studies of allopurinol in quails at 5 and 12 h (μg/g, mean ± SD, n = 3).