Caffeic acid phenethyl ester alleviated hypouricemia in hyperuricemic mice through inhibiting XOD and up-regulating OAT3

Simiao pills alleviates renal injury associated with hyperuricemia: A multi-omics analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Simiao Pills, a classical traditional Chinese medicine prescription recorded in Cheng Fang Bian Du, has been traditionally used to treat hyperuricemia due to its heat-clearing and diuretic properties. Studies have shown that Simiao Pills effectively reduce uric acid levels. However, further research is needed to elucidate the precise composition of Simiao Pills for treating hyperuricemia and their potential pharmacological mechanism.

AIM OF THE STUDY

This study aimed to investigate the therapeutic effects of Simiao Pills on hyperuricemia, with a particular focus on evaluating their protective role against hyperuricemia-induced renal injury and elucidating the underlying mechanism of action.

MATERIALS AND METHODS

UPLC-MS/MS was used to identify the components of Simiao Pills. The hyperuricemia model mice were established by intraperitoneal injecting potassium oxonate (PO) and oral administrating hypoxanthine (HX). Network pharmacology, transcriptome, and metabolomics analyses were integrated to explore the mechanism of Simiao Pills in reducing uric acid and protecting the kidney. Mechanistic and functional studies were conducted to validate the potential mechanisms.

RESULTS

Simiao Pills were found to contain 12 characteristic components. Treatment with Simiao Pills significantly reduced serum uric acid levels and ameliorated hyperuricemia-induced renal injury. Simiao Pills inhibited the enzymatic activities of XOD and XDH, and regulated the uric acid transporters in the kidney and ileum. Transcriptome and network pharmacology analyses highlighted quercetin, berberine, kaempferol, and baicalein as the principal active components of Simiao Pills acting on the kidney during hyperuricemia treatment, primarily impacting fibrosis, apoptosis, and inflammation-related signaling pathways. Metabolomic analysis unveiled 21 differential metabolites and 5 metabolic pathways associated with Simiao Pills against renal injury associated with hyperuricemia. Further experimental results validated that Simiao Pills reduced renal fibrosis, apoptotic renal cells, serum inflammation levels, and inhibited the NF-κB/NLRP3/IL-1β signaling pathway.

CONCLUSION

This study demonstrated that Simiao Pills significantly reduced serum uric acid levels and improved renal injury by regulating inflammation, apoptosis, and renal fibrosis. These findings have provided a robust scientific pharmacological basis for the use of Simiao Pills in treating hyperuricemia patients.

Shield-armed probiotic delivery system based on co-deposition of poly-dopamine and poly-lysine helps Lactiplantibacillus plantarum relieve hyperuricemia

Hyperuricemia (HUA) is a disease characterized by an abnormal metabolism of purine. Lactic acid bacteria (LAB) have attracted much attention for their safe and effective treatment of HUA by inhibiting xanthine oxidase (XOD) and regulating gut microbiota. However, the effectiveness of probiotics can be compromised by the harsh environment of the gastrointestinal tract. In preliminary experiments, Lactiplantibacillus plantarum DY1, which is generally regarded as safe (GRAS), can lower uric acid. We have devised a straightforward and efficient technique for encapsulating DY1 using a coating comprising polydopamine (PDA) co-deposited with poly-l-lysine (PLL) to obtain DY1@PDLL. TEM, SEM, FT-IR and DLS tests showed that DY1 was successfully coated. Incubate at SGF or SIF for 3 h, the number of viable bacteria of free probiotics and DY1@PDLL decreased by 0.92 and 0.46 log cfu/mL, 1.66 and 0.66 log cfu/mL, respectively. The fluorescence intensity of the intestines of the DY1@PDLL treated mice was 3.96 times that of free probiotic. Notably, DY1@PDLL can reduce the uric acid levels of HUA mice by 31.63 % and free probiotics by 18.72 % (≈1.69 times). DY1@PDLL could also regulate gut microbiota and serum metabolic profile. These findings unequivocally highlight the remarkable potential of DY1@PDLL as an exceptional oral probiotic delivery system.

Spectroscopic Relationship between XOD and TAOZHI Total Polyphenols Based on Chemometrics and Molecular Docking Techniques

Xanthine oxidase (XOD) is a key enzyme that promotes the oxidation of xanthine/hypoxanthine to form uric acid, and the accumulation of uric acid leads to hyperuricaemia. The prevalence of gout caused by hyperuricaemia is increasing year by year. TAOZHI (TZ) can be used for the treatment of rheumatic arthralgia due to qi stagnation and blood stasis and contains a large number of polyphenolic components. The aim of this study was to investigate the relationship between chromatograms and XOD inhibition of 21 batches of TZ total polyphenol extract samples. Chemometric methods such as grey correlation analysis, bivariate correlation analysis, and partial least squares regression were used to identify the active ingredient groups in the total polyphenol extracts of TZ, which were validated using molecular docking techniques. The total polyphenol content contained in the 21 batches did not differ significantly, and all batches showed inhibitory effects on XOD. Spectroeffect correlation analysis showed that the inhibitory effect of TZ on XOD activity was the result of the synergistic effect of multiple components, and the active component groups screened to inhibit XOD were F2 (4-O-Caffeoylquinic acid), F4, and F10 (naringenin). The molecular docking results showed that the binding energies of all nine dockings were lower than -7.5 kcal/mol, and the binding modes included hydrogen bonding, hydrophobic forces, salt bridges, and π-staking, and the small molecules might exert their pharmacological effects by binding to XOD through the residue sites of the amino acids, such as threonine, arginine, and leucine. This study provides some theoretical basis for the development and utilisation of TZ total polyphenols.

Effects of Smilax China L. extracts on Hyperuricemia chicken model via inhibiting xanthine oxidase activity

Hyperuricemia (HUA) is a metabolic disorder caused by excessive production of uric acid (UA) or impaired uric acid metabolism. Smilax China L. has a wide range of pharmacological activities such as immunomodulatory, anti-inflammatory, and antioxidant. Its roots and rhizomes have been widely used for the treatment of HUA. However, its mechanisms for treating HUA and reducing renal impairment have not been fully elucidated. In the present study, we evaluated the effect of Smilax China L. extract (SC) on UA metabolism and further explored its mechanism of action by feeding a high-calcium and high-protein diet to chickens to induce a model of HUA in chickens. SC significantly reduced serum UA levels and improved renal function in hyperuricemic chickens. Meanwhile, SC was able to inhibit the activity of xanthine oxidase (XOD) in vivo and in vitro, reducing the production of uric acid. In addition, SC was able to increase the expression of Breast Cancer Resistance Protein (BCRP) in the kidney and ileum and increase uric acid excretion. Therefore, our results suggest that SC may be a candidate for anti-hyperuricemia.

Study on the Underlying Mechanism of Yinhua Gout Granules in the Treatment of Gouty Arthritis by Integrating Transcriptomics and Network Pharmacology

Purpose

Yinhua Gout Granules (YGG) is a traditional Chinese medicine preparation with a variety of pharmacological effects, and its clinical efficacy in the treatment of gouty arthritis (GA) has been fully confirmed. However, the pharmacodynamic basis of YGG and its anti-inflammatory mechanism of action in GA are unknown. The objective of this study was to identify the active components and molecular mechanisms of YGG in the treatment of GA.

Methods

Ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) and network pharmacology were used to identify and predict the potential active ingredients and related signaling pathways. Then, we revealed the anti-GA effects of YGG based on pharmacodynamic experiments in GA rats. Finally, we integrated transcriptomics and network pharmacology to elucidate the potential mechanism of action and verified the putative mechanism by molecular docking, immunohistochemical (IHC) and Western blot.

Results

We have identified 10 major active components of YGG that may have anti-GA effects, such as ferulic acid, rutin, luteolin, etc. Using molecular docking, we found that 10 major compounds could bind well to TNF, PTGS2, IL-6, IL1β, NOS2 and PTGS1, and the binding energies were all less than -5 kcal/mol. Animal studies have shown that YGG can improve joint inflammation and inflammatory cell infiltration, reduce serum UA, BUN and Cr levels (p<0.01), and decrease IL-1β, IL-6, TNF-α, COX-2 and PGE2 levels in synovial tissue (p<0.01), which are associated with the pathogenesis of GA. IHC and Western blot results showed that YGG could regulate TLR4/MYD88/NF-κB pathway to inhibit the inflammatory response induced by GA.

Conclusion

This study found that YGG could not only improve the disease of GA by inhibiting the production of UA in the body, but also target the regulation of TLR4/MYD88/NF-κB signaling pathway through a variety of active components to achieve effective therapeutic effects on GA.

Analyzing chemical composition of Sargentodoxae caulis water extract and their hypouricemia effect in hyperuricemic mice

Hyperuricemia (HUA) is a metabolic disease characterized by the increase of serum uric acid (UA) level. Sargentodoxae Caulis (SC) is a commonly used herbal medicine for the treatment of gouty arthritis, traumatic swelling, and rheumatic arthritis in clinic. In this study, a total of fifteen compounds were identified in SC water extract using UHPLC-Q-TOF-MS/MS, including three phenolic acids, seven phenolic glycosides, four organic acids, and one lignan. Then, to study the hypouricemia effect of SC, a HUA mouse model was induced using a combination of PO, HX, and 20% yeast feed. After 14 days of treatment with the SC water extract, the levels of serum UA, creatinine (CRE), blood urea nitrogen (BUN) were reduced significantly, and the organ indexes were restored, the xanthine oxidase (XOD) activity were inhibited as well. Meanwhile, SC water extract could ameliorate the pathological status of kidneys and intestine of HUA mice. Additionally, quantitative real-time PCR (qRT-PCR) and western blotting results showed that SC water extract could increase the expression of ATP binding cassette subfamily G member 2 (ABCG2), organic cation transporter 1 (OCT1), organic anion transporter 1 (OAT1) and organic anion transporter 3 (OAT3), whereas decrease the expression of glucose transporter 9 (GLUT9). This study provided a data support for the clinical application of SC in the treatment of HUA.

Data mining-guided alleviation of hyperuricemia by Paeonia veitchii Lynch through inhibition of xanthine oxidase and regulation of renal urate transporters

BACKGROUND

Hyperuricemia (HUA) is a metabolic disease characterized by a high level of uric acid (UA). The extensive historical application of traditional Chinese medicine (TCM) offers a range of herbs and prescriptions used for the treatment of HUA-related disorders. However, the core herbs in the prescriptions and their mechanisms have not been sufficiently explained.

PURPOSE

Our current investigation aimed to estimate the anti-HUA effect and mechanisms of Paeonia veitchii Lynch, an herb with high use frequency identified from data mining of TCM prescriptions.

METHODS

Prescriptions for HUA/gout treatment were statistically analyzed through a data mining approach to determine the common nature and use frequency of their composition herbs. The chemical constituents of Paeonia veitchii extract (PVE) were analyzed by UPLC-QTOF-MS/MS, while its UA-lowering effect was further evaluated in adenosine-induced liver cells and potassium oxonate (PO) and hypoxanthine (HX)-induced HUA mice.

RESULTS

A total of 225 prescriptions involving 246 herbs were sorted out. The properties, flavors and meridians of the appearing herbs were mainly cold, bitter and liver, respectively, while their efficacy was primarily concentrated on clearing heat and dispelling wind. Further usage frequency analysis yielded the top 20 most commonly used herbs, in which PVE presented significant inhibitory activity (IC50 = 131.33 µg/ml) against xanthine oxidase (XOD), and its constituents showed strong binding with XOD in a molecular docking study and further were experimentally validated through XOD enzymatic inhibition and surface plasmon resonance (SPR). PVE (50 to 200 μg/ml) dose-dependently decreased UA levels by inhibiting XOD expression and activity in BRL 3A liver cells. In HUA mice, oral administration of PVE exhibited a significant UA-lowering effect, which was attributed to the reduction of UA production by inhibiting XOD activity and expression, as well as the enhancement of UA excretion by regulating renal urate transporters (URAT1, GLUT9, OAT1 and ABCG2). Noticeably, all doses of PVE treatment did not cause any liver injury, and displayed a renal protective effect.

CONCLUSIONS

Our results first comprehensively clarified the therapeutic effect and mechanisms of PVE against HUA through suppressing UA production and promoting UA excretion with hepatic and renal protection, suggesting that PVE could be a promising UA-lowering candidate with a desirable safety profile for the treatment of HUA and prevention of gout.

High levels of uric acid inhibit BAT thermogenic capacity through regulation of AMPK

Hyperuricemia (HUA) is strongly associated with the increasing prevalence of obesity, but the underlying mechanism remains elusive. Dysfunction of brown adipose tissue (BAT) could lead to obesity. However, studies on the role of HUA on BAT are lacking. Our retrospective clinical analysis showed that serum uric acid (UA) is significantly associated with BAT in humans. To investigate the role of UA in regulating BAT function, we used UA to treat primary brown adipocytes (BACs) in vitro and established HUA mice. In vitro results showed that HUA suppressed thermogenic gene expression and oxygen consumption rate. Accordingly, HUA mice exhibited lower energy expenditure and body temperature, with larger lipid droplets and lower thermogenic gene expression. These results demonstrate that HUA inhibits BAT thermogenic capacity in vitro and in vivo. To further elucidate the mechanism of UA on adipocytes, mRNA-sequencing analysis was performed and screened for "AMP-activated protein kinase (AMPK) signaling pathway" and "mitochondrial biogenesis." Further tests in vivo and in vitro showed that the phosphorylation of AMPK was suppressed by HUA. Activation of AMPK alleviated the inhibition of AMPK phosphorylation by HUA and increased mitochondrial biogenesis, subsequently restoring the impaired BAT thermogenic capacity in vitro and vivo. Thus, we confirmed that HUA suppresses mitochondrial biogenesis by regulating AMPK, thereby inhibiting BAT thermogenic capacity. Taken together, our study identifies UA as a novel regulator of BAT thermogenic capacity, providing a new strategy to combat obesity.NEW & NOTEWORTHY To investigate the effect and mechanism of UA on BAT thermogenic capacity, we established HUA models in vitro and in vivo, and performed RNA sequencing analysis. Our results revealed that HUA suppresses mitochondrial biogenesis by regulating AMPK, thereby inhibiting BAT thermogenic capacity. Taken together, our study identifies UA as a novel regulator of BAT thermogenic capacity, providing a new strategy to combat obesity.

In vitro xanthine oxidase inhibitory and in vivo anti-hyperuricemic properties of sodium kaempferol-3'-sulfonate

Xanthine oxidase (XO), a key enzyme in purine catabolism, catalyzes the oxidation of xanthine to uric acid in the body, but overproduction of uric acid may lead to hyperuricemia. This study aims to investigate in vitro XO inhibitory and in vivo anti-hyperuricemic properties of sodium kaempferol-3'-sulfonate (KS). The kinetic analysis indicates that KS is a reversible competitive inhibitor and has significant inhibitory effects on XO activity with an IC50 value of 0.338 μM. Fluorescence spectra suggested that KS could cause fluorescence quenching and conformational changes of XO due to the formation of a KS-XO complex. Molecular docking studies demonstrated that KS interacted with several amino acid residues of XO by the π-π stacking, hydrogen bonds, and hydrophobic interactions. The inhibitory mechanism of KS on XO activity might be the insertion of KS into the active site of XO to prevent the entrance of the substrate xanthine and induce conformational changes of XO. The results carried out in hyperuricemic mice showed that KS reduced serum XO activity, serum uric acid (UA), creatinine (CRE), and urea nitrogen (BUN) levels, as well as alleviating renal histopathological injury. These findings suggest that KS may be a new potent XO inhibitor against hyperuricemia-related diseases.

Ameliorative Effect of Mannuronate Oligosaccharides on Hyperuricemic Mice via Promoting Uric Acid Excretion and Modulating Gut Microbiota

Mannuronate oligosaccharide (MOS) is α-D-mannuronic acid polymer with 1,4-glycosidic linkages that possesses beneficial biological properties. The aim of this study was to investigate the hypouricemic effect of MOS in hyperuricemic mice and demonstrate the possible protective mechanisms involved. In this research, 200 mg/kg/day of MOS was orally administered to hyperuricemic mice for four weeks. The results showed that the MOS treatment significantly reduced the serum uric acid (SUA) level from 176.4 ± 7.9 μmol/L to 135.7 ± 10.9 μmol/L (p < 0.05). MOS alleviated the inflammatory response in the kidney. Moreover, MOS promoted uric acid excretion by regulating the protein levels of renal GLUT9, URAT1 and intestinal GLUT9, ABCG2. MOS modulated the gut microbiota in hyperuricemic mice and decreased the levels of Tyzzerella. In addition, research using antibiotic-induced pseudo-sterile mice demonstrated that the gut microbiota played a crucial role in reducing elevated serum uric acid of MOS in mice. In conclusion, MOS may be a potential candidate for alleviating HUA symptoms and regulating gut microbiota.