Target Screen of Anti-Hyperuricemia Compounds from Cortex Fraxini In Vivo Based on ABCG2 and Bioaffinity Ultrafiltration Mass Spectrometry

Therapeutic potential and pharmacological mechanisms of Traditional Chinese Medicine in gout treatment

Gout is a systemic metabolic disorder caused by elevated uric acid (UA) levels, affecting over 1% of the population. The most common complication of gout is gouty arthritis (GA), characterized by swelling, pain or tenderness in peripheral joints or bursae, which can lead to the formation of tophi. At present, western medicines like colchicine, febuxostat and allopurinol are the primary treatment strategy to alleviate pain and prevent flare-ups in patients with GA, but they have significant side effects and increased mortality risks. Traditional Chinese medicine (TCM) has been utilized for thousands of years for the prevention and treatment of GA, demonstrating effective control over serum UA (SUA) levels with fewer side effects. Herein we summarized a total of 541 studies published from 2000 to 2023 in sources including PubMed, Web of Science, the Cochrane Library and Embase, highlighting the therapeutic potential of TCM in treating gout and GA, particularly in combination with modern medical strategies. This review focuses on TCM formulas, Chinese herbal extracts, and active compounds derived from TCM, providing an overview of recent clinical application and the pharmacological research based on animal models and cellular systems. Particularly, the current review categorized the clinical and experimental evidence into the strategies for improving hyperuricemia, decreasing the sudden onset of acute GA and retarding chronic GA progression, supplied further coherent reference and enlightenment for clinicians, investigators of natural product chemistry, researchers in TCM and pharmacology. We hope this article will inspire the development of novel formulas and molecular entities for the treatment of gout and GA.

Hyperuricemia and its related diseases: mechanisms and advances in therapy

Hyperuricemia, characterized by elevated levels of serum uric acid (SUA), is linked to a spectrum of commodities such as gout, cardiovascular diseases, renal disorders, metabolic syndrome, and diabetes, etc. Significantly impairing the quality of life for those affected, the prevalence of hyperuricemia is an upward trend globally, especially in most developed countries. UA possesses a multifaceted role, such as antioxidant, pro-oxidative, pro-inflammatory, nitric oxide modulating, anti-aging, and immune effects, which are significant in both physiological and pathological contexts. The equilibrium of circulating urate levels hinges on the interplay between production and excretion, a delicate balance orchestrated by urate transporter functions across various epithelial tissues and cell types. While existing research has identified hyperuricemia involvement in numerous biological processes and signaling pathways, the precise mechanisms connecting elevated UA levels to disease etiology remain to be fully elucidated. In addition, the influence of genetic susceptibilities and environmental determinants on hyperuricemia calls for a detailed and nuanced examination. This review compiles data from global epidemiological studies and clinical practices, exploring the physiological processes and the genetic foundations of urate transporters in depth. Furthermore, we uncover the complex mechanisms by which the UA induced inflammation influences metabolic processes in individuals with hyperuricemia and the association with its relative disease, offering a foundation for innovative therapeutic approaches and advanced pharmacological strategies.

Alkaloid uptake pathways in renal tubular epithelial cells from different processed products of Phellodendri chinensis Cortex

This study aimed to investigate the absorption of alkaloids from Phellodendri chinensis Cortex (PC) by human renal tubular epithelial cells (HK-2). Cellular uptake and affinity ultrafiltration assays were employed to determine the alkaloid uptake pathway in HK-2 cells. Stemming from the hypothesis that salt-water processed PC introduces these alkaloids into the kidney at a cellular level, this research focused on different processed products of PC that are tailored for renal targeting. Utilizing the UPLC-QqQ-MS method, we quantified variations in the uptake capacity of phellodendrine, magnoflorine, jatrorrhizine, berberrubine, and berberine from raw Phellodendri chinensis Cortex (RPC), salt-water processed Phellodendri chinensis Cortex (SPC), and wine processed Phellodendri chinensis Cortex (WPC) in HK-2 cells. This study also tracked the concentration changes of these five alkaloids in HK-2 cells during the administration phase. Further, we evaluated the influence of two inhibitors on the absorption of these five alkaloids from PC and its processed products into HK-2 cells: the organic anion transporters (OATs) inhibitor-probenecid (PRO), and the organic cationic transporters (OCTs) inhibitor-tetraethylammonium chloride (TEAC). A pivotal component of this research was an investigation into the effects of PC and its processed products on the expression levels of OCT2, OAT1, and OAT3 proteins in HK-2 cells, facilitated by Western blot analysis. Finally, we appraised the binding affinity of PC's alkaloids to OCT2, OAT1, and OAT3 proteins using an ultrafiltration centrifugation technique. The uptake of different processed products of PC by HK-2 cells showed the following trend: SPC group > RPC group > WPC group. When considering inhibitor uptake in HK-2 cells, the group treated with PRO (an OATs inhibitor) demonstrated a higher uptake than the group treated with TEAC (an OCTs inhibitor). It was observed that different processed products of PC elevated the expression of OCT2 and OAT1 proteins in HK-2 cells. Specifically, both the SPC and berberrubine groups displayed enhanced expression of these proteins, with a marked increase noted for OCT2. Through affinity ultrafiltration assays, it was determined that the binding affinity of alkaloids from different processed products of PC to OCT2 and OAT1 significantly exceeded that to OAT3. These results indicate that PC-derived alkaloids are absorbed by HK-2 cells, predominantly through transport mechanisms mediated by OCT2 and OAT1, with OCT2 serving as the dominant transporter. The higher intake of alkaloids in SPC group can likely be linked to the amplified activity of kidney uptake transporters.