Bioactivity-guided separation of potential α-glycosidase inhibitor from clerodendranthus spicatus based on HSCCC coupled with molecular docking

Anti-hyperuricemia effect of Clerodendranthus spicatus: a molecular biology study combined with metabolomics

Hyperuricemia (HUA), a metabolic disease caused by excessive production or decreased excretion of uric acid (UA), has been reported to be closely associated with a variety of UA transporters. Clerodendranthus spicatus (C. spicatus) is an herbal widely used in China for the treatment of HUA. However, the mechanism has not been clarified. Here, the rat model of HUA was induced via 10% fructose. The levels of biochemical indicators, including UA, xanthine oxidase (XOD), adenosine deaminase (ADA), blood urea nitrogen (BUN), and creatinine (Cre), were measured. Western blotting was applied to explore its effect on renal UA transporters, such as urate transporter1 (URAT1), glucose transporter 9 (GLUT9), and ATP-binding cassette super-family G member 2 (ABCG2). Furthermore, the effect of C. spicatus on plasma metabolites was identified by metabolomics. Our results showed that C. spicatus could significantly reduce the serum levels of UA, XOD, ADA and Cre, and improve the renal pathological changes in HUA rats. Meanwhile, C. spicatus significantly inhibited the expression of URAT1 and GLUT9, while increased the expression of ABCG2 in a dose-dependent manner. Metabolomics showed that 13 components, including 1-Palmitoyl-2-Arachidonoyl-sn-glycero-3-PE, Tyr-Leu and N-cis-15-Tetracosenoyl-C18-sphingosine, were identified as potential biomarkers for the UA-lowering effect of C. spicatus. In addition, pathway enrichment analysis revealed that arginine biosynthesis, biosynthesis of amino acids, pyrimidine metabolism and other metabolic pathways might be involved in the protection of C. spicatus against HUA. This study is the first to explore the mechanism of anti-HUA of C. spicatus through molecular biology and metabolomics analysis, which provides new ideas for the treatment of HUA.

Kidney tea [Orthosiphon aristatus (Blume) Miq.] improves diabetic nephropathy via regulating gut microbiota and ferroptosis

Introduction

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease. Due to its complex pathogenesis, new therapeutic agents are urgently needed. Orthosiphon aristatus (Blume) Miq., commonly known as kidney tea, is widely used in DN treatment in China. However, the mechanisms have not been fully elucidated.

Methods

We used db/db mice as the DN model and evaluated the efficacy of kidney tea in DN treatment by measuring fasting blood glucose (FBG), serum inflammatory cytokines, renal injury indicators and histopathological changes. Furthermore, 16S rDNA gene sequencing, untargeted serum metabolomics, electron microscope, ELISA, qRT-PCR, and Western blotting were performed to explore the mechanisms by which kidney tea exerted therapeutic effects.

Results

Twelve polyphenols were identified from kidney tea, and its extract ameliorated FBG, inflammation and renal injury in DN mice. Moreover, kidney tea reshaped the gut microbiota, reduced the abundance of Muribaculaceae, Lachnoclostridium, Prevotellaceae_UCG-001, Corynebacterium and Akkermansia, and enriched the abundance of Alloprevotella, Blautia and Lachnospiraceae_NK4A136_group. Kidney tea altered the levels of serum metabolites in pathways such as ferroptosis, arginine biosynthesis and mTOR signaling pathway. Importantly, kidney tea improved mitochondrial damage, increased SOD activity, and decreased the levels of MDA and 4-HNE in the renal tissues of DN mice. Meanwhile, this functional tea upregulated GPX4 and FTH1 expression and downregulated ACSL4 and NCOA4 expression, indicating that it could inhibit ferroptosis in the kidneys.

Conclusion

Our findings imply that kidney tea can attenuate DN development by modulating gut microbiota and ferroptosis, which presents a novel scientific rationale for the clinical application of kidney tea.

Clerodendranthus Spicatus: A review of its active compounds, mechanisms of action, and clinical studies in urinary diseases

Clerodendranthus spicatus (Thunb.) C.Y.Wu (CS) is a widely studied plant that shows potential in treating urinary diseases. Previous studies have focused on its chemical composition, pharmacological effects, and clinical applications. This review aims to provide a comprehensive summary and evaluation of the existing literature on CS. It also suggests future research directions to increase our understanding of its medicinal value. 129 pieces of literature were selected from several databases, including PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), Wan-fang Database, and Google Scholar, and were analyzed. Forty-five active compounds of CS have pharmacological effects such as lowering uric acid, anti-inflammation, anti-oxidation, and kidney protection. The potential mechanisms of these effects may be related to inhibiting transforming growth factor β1 (TGF-β1) activation, reducing inflammatory factors such as IL-8, IL-1β, TNF-α, PGE2, IFN-γ, and IL-6 levels, suppressing the activation of NF-κB, JAK/STAT pathway, enhancing the clearance of ROS, MDA DPPH·, and O2 ̇ -, and regulating the expression of apoptosis-related pathways and proteins. This paper also discusses the quality control of CS and its efficacy and safety in treating urinary diseases. The study concludes that CS has a high potential for treating urinary diseases. Future studies should focus on observing the metabolic changes of CS active compounds in vivo and investigating the effects of CS on key signaling pathways. Additionally, more standardized and reasonable clinical studies and safety evaluation experiments should be conducted to obtain more clinical data.

Separation of rare earth element radioisotopes by reverse-phase high-speed counter-current chromatography

Analytical scale purification of rare earth element (REE) radioisotopes is typically accomplished using cation-exchange resins (e.g. AG 50W-X8) and high-performance liquid chromatography (HPLC). Despite the variety of improvements made since the development of this separation process in the 1950s, nearest neighbor separations remain a challenge, as does the issue of irreversible sample adsorption. Herein, we report a study that evaluates the potential of high-speed counter-current chromatography (HSCCC) as an alternative method for purifying REE elements, with specific reference to separations of fission product REE of interest to nuclear forensics. Complementary HSCCC REE separation experiments, one spiked with radiotracer and REE fission product activity, allowed for in depth analysis of resulting fractions from both an elemental (inductively coupled plasma atomic emission spectroscopy, ICP-AES) and radiological (gamma-ray spectrometry, beta counting) purity perspective. The highly reproducible nature of separation profiles generated from HSCCC instruments was leveraged to simplify work-up of samples containing radioisotopes. Subsequent radioanalytical evaluation revealed minimal carryover of Eu into neighboring Sm and Tb fractions (as indicated by presence of 150Eu), and trace contamination of the Tb fraction with Y (as indicated by presence of 91Y). Subtle differences in stationary phase retention across the two columns were reflected in significant variations in decontamination factors of duplicate parallel separations. These differences paired with obtained distribution of radioisotopes provided valuable insights into future improvements. Collectively, this study represents a significant step forward in development of HSCCC technology for task specific REE radioisotope purification.

Study on the mechanism of Orthosiphon aristatus (Blume) Miq. in the treatment of hyperuricemia by microbiome combined with metabonomics

ETHNOPHARMACOLOGICAL RELEVANCE

Growing evidence indicates that hyperuricemia is closely associated with gut microbiota dysbiosis. Orthosiphon aristatus (Blume) Miq. (O. aristatus), as a traditional Chinese medicine, has been widely used to treat hyperuricemia in China. However, the mechanism by which O. aristatus treats hyperuricemia has not been clarified.

AIM OF THE STUDY

In this study, we investigated whether the molecular mechanism underlying the anti-hyperuricemia effect of O. aristatus is related to the regulation of gut microbiota by 16S rDNA gene sequencing combined with widely targeted metabolomics.

MATERIALS AND METHODS

Hyperuricemia was induced in rats by administration of 10% fructose and 20% yeast, and the uricosuric effect was assessed by measuring the uric acid (UA) levels in serum and cecal contents. Intestinal morphology was observed by hematoxylin and eosin (HE) staining. To explore the effects of O. aristatus on the gut microbiota and its metabolites, we utilized 16S rDNA gene sequencing combined with widely targeted metabolomics. Furthermore, metabolic pathway enrichment analysis was performed on the screened differential metabolites. The real time quantitative polymerase chain reaction (RT-PCR) and western blotting (WB) were used to detect the expression of relevant proteins in the key pathway.

RESULTS

Our results indicated that O. aristatus intervention decreased serum UA levels and increased the UA levels in cecal contents in hyperuricemic rats. Additionally, O. aristatus improved intestinal morphology and altered the composition of the gut microbiota and its metabolites. Specifically, 16S rDNA revealed that O. aristatus treatment significantly reduced the abundance of unidentified-Ruminococcaceae and Lachnospiraceae-NK4A136-group. Meanwhile, widely targeted metabolomics showed that 17 metabolites, including lactose, 4-oxopentanoate and butyrate, were elevated, while 55 metabolites, such as flavin adenine dinucleotide and xanthine, were reduced. Metabolic pathway enrichment analysis found that O. aristatus was mainly involved in purine metabolism. Moreover, RT-PCR and WB suggested that O. aristatus could significantly up-regulate the expression of UA excretion transporter ATP-binding cassette subfamily G member 2 (ABCG2) in the intestine.

CONCLUSION

O. aristatus exerts UA-lowering effect by regulating the gut microbiota and ABCG2 expression, indicating that this herb holds great promise in the treatment of hyperuricemia.

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

The ATP-binding cassette (ABC) transporter ABCG2 is a significant urate transporter with a high capacity, and it plays a crucial role in the development of hyperuricemia and gout. Therefore, it has the potential to be targeted for therapeutic interventions. Cortex Fraxini, a traditional Chinese medicine (TCM), has been found to possess anti-hyperuricemia properties. However, the specific constituents of Cortex Fraxini responsible for this effect are still unknown, particularly the compound that is responsible for reducing uric acid levels in vivo. In this study, we propose a target screening protocol utilizing bio-affinity ultrafiltration mass spectrometry (BA-UF-MS) to expediently ascertain ABCG2 ligands from the plasma of rats administered with Cortex Fraxini. Our screening protocol successfully identified fraxin as a potential ligand that interacts with ABCG2 when it functions as the target protein. Subsequent investigations substantiated fraxin as an activated ligand of ABCG2. These findings imply that fraxin exhibits promise as a drug candidate for the treatment of hyperuricemia. Furthermore, the utilization of BA-UF-MS demonstrates its efficacy as a valuable methodology for identifying hit compounds that exhibit binding affinity towards ABCG2 within TCMs.

A Systematic Review of Orthosiphon stamineus Benth. in the Treatment of Diabetes and Its Complications

(1) Background: Orthosiphon stamineus Benth. is a traditional medicine used in the treatment of diabetes and chronic renal failure in southern China, Malaysia, and Thailand. Diabetes is a chronic metabolic disease and the number of diabetic patients in the world is increasing. This review aimed to systematically review the effects of O. stamineus in the treatment of diabetes and its complications and the pharmacodynamic material basis. (2) Methods: This systematic review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), using the databases ScienceDirect, PubMed, and Web of Science. (3) Results: Thirty-one articles related to O. stamineus and diabetes were included. The mechanisms of O. stamineus in the treatment of diabetes and its complications mainly included inhibiting α-amylase and α-glucosidase activities, antioxidant and anti-inflammatory activities, regulating lipid metabolism, promoting insulin secretion, ameliorating insulin resistance, increasing glucose uptake, promoting glycolysis, inhibiting gluconeogenesis, promoting glucagon-likepeptide-1 (GLP-1) secretion and antiglycation activity. Phenolic acids, flavonoids and triterpenoids might be the main components for hypoglycemia effects in O. stamineus. (4) Conclusion: O. stamineus could be an antidiabetic agent to treat diabetes and its complications. However, it needs further study on a pharmacodynamic substance basis and the mechanisms of effective constituents.

Separation and Identification of Antioxidants and Aldose Reductase Inhibitors in Lepechinia meyenii (Walp.) Epling

We previously reported that Lepechinia meyenii (Walp.) Epling has antioxidant and aldose reductase (AR) inhibitory activities. In this study, L. meyenii was extracted in a 50% MeOH and CH₂Cl₂/MeOH system. The active extracts of MeOH and 50% MeOH were subjected to fractionation, followed by separation using high-speed counter-current chromatography (HSCCC) and preparative HPLC. Separation and identification revealed the presence of caffeic acid, hesperidin, rosmarinic acid, diosmin, methyl rosmarinate, diosmetin, and butyl rosmarinate. Of these, rosmarinic acid, methyl rosmarinate, and butyl rosmarinate possessed remarkable antioxidant and AR inhibitory activities. The other compounds were less active. In particular, rosmarinic acid is the key contributor to the antioxidant and AR inhibitory activities of L. meyenii; it is rich in the MeOH extract (333.84 mg/g) and 50% MeOH extract (135.41 mg/g) of L. meyenii and is especially abundant in the EtOAc and n-BuOH fractions (373.71-804.07 mg/g) of the MeOH and 50% MeOH extracts. The results clarified the basis of antioxidant and AR inhibitory activity of L. meyenii, adding scientific evidence supporting its traditional use as an anti-diabetic herbal medicine. The HSCCC separation method established in this study can be used for the preparative separation of rosmarinic acid from natural products.