Apigenin Ameliorates Hyperuricemia and Renal Injury through Regulation of Uric Acid Metabolism and JAK2/STAT3 Signaling Pathway

Fuling-Zexie formula attenuates hyperuricemia-induced nephropathy and inhibits JAK2/STAT3 signaling and NLRP3 inflammasome activation in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Fuling-Zexie (FZ) formula, a traditional Chinese herbal prescription composed of Poria cocos (Schwan.) Wolf. (Poria), Pueraria lobate (Willd.) Howe. (Puerariae Lobatae Radix), Alisma orientale (Sam.) Julep. (Alismatis Rhizoma), and Atractylodes lancea (Thunb.) Dc. (Atractylodis Rhizoma), has been clinically used to ameliorate hyperuricemia (HUA) and its associated renal injury.

AIM OF STUDY

This study aims to explore the action and mechanism of FZ on renal inflammation and dysfunction caused by HUA.

MATERIALS AND METHODS

FZ was orally administered to rapid HUA mouse induced by potassium oxonate (PO) and hypoxanthine (HX) for 7 days. Serum levels of uric acid (UA), creatinine (CRE), blood urea nitrogen (BUN), xanthine oxidase (XOD), adenosine deaminase (ADA), alanine aminotransferase (ALT), aspartate aminotransferase (AST), urine levels of UA, CRE and urinary albumin were determined by biochemical assays. Serum levels of interleukin (IL)-1β and IL-6 were tested by ELISA. Hematoxylin-eosin and Masson staining were used to examine kidney and liver histopathological alterations. The expressions of renal glucose transporter 9 (GLUT9), ATP-binding cassette subfamily G member 2 (ABCG2), organic anion transporter 1 (OAT1), phospho-janus kinase 2 (p-JAK2), p-signal transducer and activator of transcription 3 (p-STAT3), suppression of cytokine signaling 3 (SOCS3), NLR family pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein (ASC), and cleaved-cysteinyl aspartate specific proteinase-1 (cleaved-Cas-1) were detected by western blots. The potential protein targets and pathways of FZ intervention on HUA were predicted by network pharmacology. The constituents in FZ aqueous extract were analyzed by UPLC-MS.

RESULTS

FZ reduced serum UA, CRE, BUN, and urinary albumin and increased urine UA, CRE levels in HUA mice. In addition, the treatment with FZ to HUA mice inhibited the elevated serum levels of XOD and ADA, and regulated renal urate transports including OAT1, GLUT9 and ABCG2. FZ also attenuated kidney inflammation and fibrosis and downregulated the expressions of IL-1β, p-JAK2, p-STAT3, SOCS3, IL-6, NLRP3, ASC, and cleaved-Cas-1. Thirteen compounds were identified in the FG, including L-phenylalanine, D-tryptophan, 3'-hydroxypuerarin, Puerarin, 3'-Methoxy Puerarin, Daidzin, Pueroside A, formononetin-8-C- [xylosyl (1→6)]-glucoside, Ononin, Alisol I 23-acetate, 16-oxo-alisol A, Alisol C and Alisol A.

CONCLUSION

FZ inhibits serum UA generation and promotes urine UA excretion as well as attenuates kidney inflammation and fibrosis in HUA mouse with nephropathy. The underlying mechanism of its action may be associated with suppression of the JAK2/STAT3 signaling pathway and NLRP3 inflammasome activation. This formula may offer a novel source for developing anti-HUA drugs.

Simiao San alleviates hyperuricemia and kidney inflammation by inhibiting NLRP3 inflammasome and JAK2/STAT3 signaling in hyperuricemia mice

ETHNOPHARMACOLOGICAL RELEVANCE

Simiao San (SmS), a famous traditional Chinese formula, is clinically used to treat patients with hyperuricemia (HUA). However, its mechanism of action on lowering uric acid (UA) and inhibiting inflammation still deserves further investigation.

AIM OF THE STUDY

To examine the effect and its possible underlying mechanism of SmS on UA metabolism and kidney injury in HUA mouse.

MATERIALS AND METHODS

The HUA mouse model was constructed with the combined administration of both potassium oxalate and hypoxanthine. The effects of SmS on UA, xanthine oxidase (XOD), creatinine (CRE), blood urea nitrogen (BUN), interleukin-10 (IL-10), interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) were determined by ELISA or biochemical assays. Hematoxylin and eosin (H&E) was used to observe pathological alterations in the kidneys of HUA mice. The expression levels of organic anion transporter 1 (OAT1), recombinant urate transporter 1 (URAT1), glucose transporter 9 (GLUT9), nucleotide binding domain and leucine rich repeat pyrin domain containing 3 (NLRP3), Cleaved-Caspase 1, apoptosis-associated speck like protein (ASC), nuclear factor kappa-B (NF-κB), IL-6, janus kinase 2 (JAK2), phosphor (P)-JAK2, signal transducers and activators of transcription 3 (STAT3), P-STAT3, suppressor of cytokine signaling 3 (SOCS3) were examined by Western blot and/or immunohistochemical (IHC) staining. The major ingredients in SmS were identified by a HPLC-MS assay.

RESULTS

HUA mouse exhibited an elevation in serum levels of UA, BUN, CRE, XOD, and the ratio of urinary albumin to creatinine (UACR), and a decline in urine levels of UA and CRE. In addition, HUA induces pro-inflammatory microenvironment in mouse, including an increase in serum levels of IL-1β, IL-6, and TNF-α, and renal expressions of URAT1, GULT9, NLRP3, ASC, Cleaved-Caspase1, P-JAK2/JAK2, P-STAT3/STAT3, and SOCS3, and a decrease in serum IL-10 level and renal OAT1 expression as well as a disorganization of kidney pathological microstructure. In contrast, SmS intervention reversed these alterations in HUA mouse.

CONCLUSION

SmS could alleviate hyperuricemia and renal inflammation in HUA mouse. The action mechanisms behind these alterations may be associated with a limitation of the NLRP3 inflammasome and JAK2/STAT3 signaling pathways.

Dispelling Dampness, Relieving Turbidity and Dredging Collaterals Decoction, Attenuates Potassium Oxonate-Induced Hyperuricemia in Rat Models

Purpose

Dispelling dampness, relieving turbidity and dredging collaterals decoction (DED), is a traditional Chinese medicine used in the treatment of hyperuricemia. We aimed to explore the effect and mechanism of DED in the treatment of hyperuricemia.

Methods

The effects of DED (9.48, 4.74, and 2.37 g/kg/d) on potassium oxonate (750 mg/kg/d)-induced hyperuricemia in rats were evaluated by serum uric acid (UA), creatinine (CRE), blood urea nitrogen (BUN), and renal pathological changes. Network pharmacology was used to identify the effective components and targets of DED, and the key targets and signaling pathways for its effects on hyperuricemia were screened. Molecular docking was used to predict the action of DED. H&E, immunohistochemistry, WB, and PCR were used to validate the network pharmacology results.

Results

DED can effectively alleviate hyperuricemia, inhibit UA, CRE, BUN, and xanthine oxidase (XOD) activity, and reduce renal inflammatory cell infiltration and glomerular atrophy. The experiment identified 27 potential targets of DED for hyperuricemia, involving 9 components: wogonin, stigmasterol 3-O-beta-D-glucopyranoside, 3β-acetoxyatractylone, beta-sitosterol, stigmasterol, diosgenin, naringenin, astilbin, and quercetin. DED can relieve hyperuricemia mainly by inhibiting RAGE, HMGB1, IL17R, and phospho-TAK1, and by regulating the AGE-RAGE and IL-17 signaling pathways.

Conclusion

DED can alleviate hyperuricemia by inhibiting XOD activity and suppressing renal cell apoptosis and inflammation via the AGE-RAGE signaling pathway and IL-17 signaling pathway. This study provides a theoretical basis for the clinical application of DED.

The multifaceted nature of IL-10: regulation, role in immunological homeostasis and its relevance to cancer, COVID-19 and post-COVID conditions

Interleukin-10 (IL-10) is a pleiotropic cytokine that has a fundamental role in modulating inflammation and in maintaining cell homeostasis. It primarily acts as an anti-inflammatory cytokine, protecting the body from an uncontrolled immune response, mostly through the Jak1/Tyk2 and STAT3 signaling pathway. On the other hand, IL-10 can also have immunostimulating functions under certain conditions. Given the pivotal role of IL-10 in immune modulation, this cytokine could have relevant implications in pathologies characterized by hyperinflammatory state, such as cancer, or infectious diseases as in the case of COVID-19 and Post-COVID-19 syndrome. Recent evidence proposed IL-10 as a predictor of severity and mortality for patients with acute or post-acute SARS-CoV-2 infection. In this context, IL-10 can act as an endogenous danger signal, released by tissues undergoing damage in an attempt to protect the organism from harmful hyperinflammation. Pharmacological strategies aimed to potentiate or restore IL-10 immunomodulatory action may represent novel promising avenues to counteract cytokine storm arising from hyperinflammation and effectively mitigate severe complications. Natural bioactive compounds, derived from terrestrial or marine photosynthetic organisms and able to increase IL-10 expression, could represent a useful prevention strategy to curb inflammation through IL-10 elevation and will be discussed here. However, the multifaceted nature of IL-10 has to be taken into account in the attempts to modulate its levels.

Correction: Liu et al. Apigenin Ameliorates Hyperuricemia and Renal Injury through Regulation of Uric Acid Metabolism and JAK2/STAT3 Signaling Pathway. Pharmaceuticals 2022, 15, 1442

In the original publication [...].

Emodin, a Natural Anthraquinone, Increases Uric Acid Excretion in Rats with Potassium Oxonate-Induced Hyperuricemia

The treatment of hyperuricemia and gout is mostly based on lowering serum uric acid levels using drugs, such as allopurinol, or increasing urinary excretion of uric acid. However, some patients still experience adverse reactions to allopurinol and turn to Chinese medicine as an alternative. Therefore, it is crucial to design a preclinical study to obtain more convincing data on the treatment of hyperuricemia and gout with Chinese medicine. This study aimed to explore the therapeutic effect of emodin, a Chinese herbal extract, in a rat model of hyperuricemia and gout. In this study, we used 36 Sprague-Dawley rats, which were randomly divided into six groups for experimentation. Hyperuricemia was induced in rats by intraperitoneal injections of potassium oxonate. The efficacy of emodin in reducing serum uric acid levels was demonstrated by comparing the positive control group with groups treated with three different concentrations of emodin. The inflammatory profiles, including interleukin (IL)-1β, IL-6, and tumor necrosis factor-α levels, were unaffected by emodin treatment. In the experimental results, it was observed that the serum uric acid concentration in the vehicle control group was 1.80 ± 1.14, while the concentrations in the moderate and high concentration emodin groups were 1.18 ± 0.23 and 1.12 ± 0.57, resulting in no significant difference in uric acid concentration between these treatment groups and the control group, indicating that emodin has a therapeutic effect on hyperuricemia. The increase in the fractional excretion of uric acid (FEUA) demonstrated that emodin promoted urinary uric acid excretion without significantly affecting the inflammatory profile. Thus, emodin reduced the serum uric acid concentration to achieve effective treatment of hyperuricemia and gout by increasing urinary excretion. These results were supported by the measured serum uric acid and FEUA levels. Our data have potential implications for the treatment of gout and other types of hyperuricemia in clinical practice.

Lactobacillus acidophilus Fermented Dandelion Improves Hyperuricemia and Regulates Gut Microbiota

Foodborne prevention and treatment of hyperuricemia (HUA) has received widespread attention. Lactic acid bacteria (LAB) can improve intestinal function, while traditional medicine dandelion has the functions of detoxification and detumescence. Whether LAB fermented dandelion has any effects on HUA and the underlying mechanism is not clear. To address these questions, Lactobacillus acidophilus was selected or maximal xanthine oxidase activity. The effect of Lactobacillus acidophilus fermented dandelion (LAFD) on uric acid metabolism was evaluated by the HUA mouse model. Expression levels of UA, BUN, CRE, XOD, and inflammatory factors in serum were detected. Paraffin sections and staining were used to observe the kidney and small intestine, and mRNA expression of GLUT9, URAT1, OAT1, and ABCG2 related to uric acid metabolism were investigated. Furthermore, the intestinal flora was studied by contents of the cecum and high throughput 16S rRNA sequencing. The results showed that LAFD had a significant inhibitory effect on XOD in vitro (p < 0.01). LAFD could reduce the levels of UA, BUN, CRE, XOD, IL-1 β, IL-6, and TNF- α in serum (p < 0.05), thus inhibiting inflammatory reaction, and reducing UA by decreasing the mRNA expression of GLUT9, URAT1 in kidney and increasing the mRNA expression of OAT1 and ABCG2 in kidney and small intestine (p < 0.05). In addition, the 16S rRNA gene sequencing analysis demonstrated that LAFD treatment can help restore the imbalance of the intestinal microbial ecosystem and reverse the changes in Bacterodietes/Firmicutes, Muribaculaceae, Lachnospiraceae in mice with HUA. It is suggested that the mechanism of LAFD in treating HUA may be related to the regulation of the mRNA expressions of GLUT9, URAT1, OAT1, and ABCG2 in the kidney and small intestine, as well as the regulation of intestinal flora, which provides the experimental basis for the development of new plant fermented products.