Epiberberine: a potential rumen microbial urease inhibitor to reduce ammonia release screened by targeting UreG.

Rumen microbial urease inhibitors have been proposed for regulating nitrogen emission and improving nitrogen utilization efficiency in ruminant livestock industry. However, studies on plant-derived natural inhibitors of rumen microbial urease are limited. Urease accessory protein UreG, plays a crucial role in facilitating urease maturation, is a new target for design of urease inhibitor. The objective of this study was to select the potential effective inhibitor of rumen microbial urease from major protoberberine alkaloids in Rhizoma Coptidis by targeting UreG. Our results showed that berberine chloride and epiberberine exerted superior inhibition potential than other alkaloids based on GTPase activity study of UreG. Berberine chloride inhibition of UreG was mixed type, while inhibition kinetics type of epiberberine was uncompetitive. Furthermore, epiberberine was found to be more effective than berberine chloride in inhibiting the combination of nickel towards UreG and inducing changes in the second structure of UreG. Molecular modeling provided the rational structural basis for the higher inhibition potential of epiberberine, amino acid residues in G1 motif and G3 motif of UreG formed interactions with D ring of berberine chloride, while interacted with A ring and D ring of epiberberine. We further demonstrated the efficacy of epiberberine in the ruminal microbial fermentation with low ammonia release and urea degradation. In conclusion, our study clearly indicates that epiberberine is a promising candidate as a safe and effective inhibitor of rumen microbial urease and provides an optimal strategy and suitable feed additive for regulating nitrogen excretion in ruminants in the future. KEY POINTS: • Epiberberine is the most effective inhibitor of rumen urease from Rhizoma Coptidis. • Urease accessory protein UreG is an effective target for design of urease inhibitor. • Epiberberine may be used as natural feed additive to reducing NH3 release in ruminants.

Epiberberine inhibits bone metastatic breast cancer-induced osteolysis.

ETHNOPHARMACOLOGICAL RELEVANCE: The anti-tumor related diseases of Coptidis Rhizoma (Huanglian) were correlated with its traditional use of removing damp-heat, clearing internal fire, and counteracting toxicity. In the recent years, Coptidis Rhizoma and its components have drawn extensive attention toward their anti-tumor related diseases. Besides, Coptidis Rhizoma is traditionally used as an anti-inflammatory herb. Epiberberine (EPI) is a significant alkaloid isolated from Coptidis Rhizoma, and exhibits multiple pharmacological activities including anti-inflammatory. However, the effect of epiberberine on breast cancer and the inflammatory factors of metastatic breast cancer-induced osteolysis has not been demonstrated clearly. AIM OF THE STUDY: Bone metastatic breast cancer can lead to osteolysis via inflammatory factors-induced osteoclast differentiation and function. In this study, we try to analyze the effect of epiberberine on breast cancer and the inflammatory factors of metastatic breast cancer-induced osteolysis. METHODS: To evaluate whether epiberberine could suppress bone metastatic breast cancer-induced osteolytic damage, healthy female Balb/c mice were intratibially injected with murine triple-negative breast cancer 4T1 cells. Then, we examined the inhibitory effect and underlying mechanism of epiberberine on breast cancer-induced osteoclastogenesis in vitro. Xenograft assay was used to study the effect of epiberberine on breast cancer cells in vivo. Moreover, we also studied the inhibitory effects and underlying mechanisms of epiberberine on RANKL-induced osteoclast differentiation and function in vitro. RESULTS: The results show that epiberberine displayed potential therapeutic effects on breast cancer-induced osteolytic damage. Besides, our results show that epiberberine inhibited breast cancer cells-induced osteoclast differentiation and function by inhibiting secreted inflammatory cytokines such as IL-8. Importantly, we found that epiberberine directly inhibited RANKL-induced differentiation and function of osteoclast without cytotoxicity. Mechanistically, epiberberine inhibited RANKL-induced osteoclastogensis via Akt/c-Fos signaling pathway. Furthermore, epiberberine combined with docetaxel effectively protected against bone loss induced by metastatic breast cancer cells. CONCLUSIONS: Our findings suggested that epiberberine may be a promising natural compound for treating bone metastatic breast cancer-induced osteolytic damage by inhibiting IL-8 and is worthy of further exploration in preclinical and clinical trials.

Activation of NRF2 by epiberberine improves oxidative stress and insulin resistance in T2DM mice and IR-HepG2 cells in an AMPK dependent manner.

ETHNOPHARMACOLOGICAL RELEVANCE: Phytochemical compounds offer a distinctive edge in diabetes management, attributed to their multifaceted target mechanisms and minimal toxicological profiles. Epiberberine (EPI), an alkaloid derived from plants of the Rhizoma Coptidis, has been reported to have antidiabetic effects. However, the underlying molecular mechanism of EPI are not fully elucidated. AIM OF THE STUDY: This study explored the anti-diabetic effects of EPI and the role of the NRF2/AMPK signaling pathway in improving insulin resistance. MATERIALS AND METHODS: We utilized two distinct models: in vivo, we employed mice with type 2 diabetes mellitus (T2DM) induced by high-fat diet (HFD) and streptozotocin (STZ) to conduct a range of assessments including measuring physical parameters, conducting biochemical analyses, examining histopathology, and performing Western blot tests. In parallel, in vitro experiments were carried out using insulin resistance (IR)-HepG2 cells, through which we conducted a CCK8 assay, glucose uptake tests, Western blot analyses, and flow cytometry studies. RESULTS: In the EPI-treated group of T2DM mice, there was a significant reduction in hyperglycemia, IR, and hyperlipidemia, accompanied by beneficial changes in the liver and pancreas, as well as enhanced glucose uptake in IR-HepG2 cells. Herein, our finding also provided evidence that EPI could increase the expression of GLUT4 and activated the IRS-1/PI3K/AKT insulin signaling pathway to improve IR in vitro and in vivo. Moreover, EPI alleviated oxidative stress by enhancing SOD and GPX-px activity, decreasing reactive oxygen species (ROS) and malondialdehyde (MDA) content, and promoting nuclear factor (erythroid-derived 2)-like 2 (NRF2), total NRF2, NAD(P)H-quinone oxidoreductase (NQO1) and heme oxygenase-1 (HO-1) expression in the liver tissue of T2DM mice and IR-HepG2 cells. Furthermore, EPI decreased oxidative stress and improved IR, but these benefits were nullified by siNRF2 transfection. In particular, AMP-activated protein kinase (AMPK) deficiency by short-hairpin RNA (shRNA) partially reversed the effects of EPI on nuclear transcription, oxidative stress, and IR of NRF2 in IR-HepG2 cells. CONCLUSIONS: Taken together, EPI activated NRF2-dependent AMPK cascade to protect T2DM from oxidative stress, thereby alleviating IR.

Rubropunctatin-silver composite nanoliposomes for eradicating Helicobacter pylori in vitro and in vivo.

Helicobacter pylori (H. pylori) is a major factor in peptic ulcer disease and gastric cancer, and its infection rate is rising globally. The efficacy of traditional antibiotic treatment is less effective, mainly due to bacterial biofilms and the formation of antibiotic resistance. In addition, H. pylori colonizes the gastrointestinal epithelium covered by mucus layers, the drug must penetrate the double barrier of mucus layer and biofilm to reach the infection site and kill H. pylori. The ethanol injection method was used to synthesize nanoliposomes (EPI/R-AgNPs@RHL/PC) with a mixed lipid layer containing rhamnolipids (RHL) and phosphatidylcholine (PC) as a carrier, loaded with the urease inhibitor epiberberine (EPI) and the antimicrobial agent rubropunctatin silver nanoparticles (R-AgNPs). EPI/R-AgNPs@RHL/PC had the appropriate size, negative charge, and acid sensitivity to penetrate mucin-rich mucus layers and achieve acid-responsive drug release. In vitro experiments demonstrated that EPI/R-AgNPs@RHL/PC exhibited good antibacterial activity, effectively inhibited urease activity, removed the mature H. pylori biofilm, and inhibited biofilm regeneration. In vivo antibacterial tests showed that EPI/R-AgNPs@RHL/PC exhibited excellent activity in eradicating H. pylori and protecting the mucosa compared to the traditional clinical triple therapy, providing a new idea for the treatment of H. pylori infection.

Epiberberine induced p53/p21-dependent G2/M cell cycle arrest and cell apoptosis in gastric cancer cells by activating γ-aminobutyric acid receptor- ß3.

BACKGROUND AND PURPOSE: Epiberberine (EPI) is one of the most important bioalkaloid found in the rhizome of Coptis chinensis, which has been observed to exhibit pharmaceutical effects against gastric cancer (GC). Nevertheless, the potential mechanism of EPI against GC cells still remains unclear. This study aimed to identify the core receptor on GC cells through which EPI inhibited the growth of GC cells and to explore the underlying inhibitory mechanisms. METHODS: To identify hub receptor targets that respond to EPI treatment, RNA sequencing (RNA-Seq) data from a tumor-bearing mouse model were analyzed using bioinformatics method and molecular docking. The binding interaction between EPI and GABRB3 was validated through western blotting based-cellular thermal shift assay (WB-CETSA). To further verify the binding region between EPI and GABRB3 through circular dichroism (CD) chromatography, fragments of the extracellular and transmembrane domains of the GABRB3 protein were expressed and purified in vitro. Stable cell lines with the overexpression or knockdown of GABRB3 were established using the recombinant lentivirus system. MTT ((3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide)) assay, colony formation assay, invasion and migration experiments, and flow cytometry were conducted to validate the inhibitory effect of EPI on the GC cells via GABRB3. Additionally, western blotting was utilized to explore the potential inhibitory mechanisms. RESULTS: Through the combination of multiple bioinformatics methods and molecular docking, we found that the γ-aminobutyric acid type A receptor subunit -ß3 (GABRB3) might be the critical receptor target in response to EPI treatment. The results of WB-CETSA analysis indicated that EPI significantly promoted the thermostability of the GABRB3 protein. Importantly, EPI could directly bind to GABRB3 and alter the secondary structure of GABRB3 fragments similar to the natural agonist, γ-aminobutyric acid (GABA). The EPI-induced suppression of the malignant phenotype of GC cells was dependent on the presence of GABRB3. GABRB3 expression was positively correlated with TP53 in patients with GC. The binding of EPI to GABRB3 stimulated p53 accumulation in GC cells. This activated the p21/CDK1/cyclinB1 pathway, resulting in G2/M cell cycle arrest, and induced the Bcl-2/BAX/Caspase axis-dependent cell apoptosis. CONCLUSION: This study revealed the target receptor for EPI in GC cells and provided new insights into its anticancer mechanisms.

Epiberberine suppresses the metastasis of head and neck squamous cell carcinoma cells by regulating the MMP-13 and JNK pathway.

Head and neck squamous cell carcinoma (HNSCC) is one of the most common histological types of head and neck cancer. Epiberberine is a potent antitumour agent for several types of cancer. This study is aimed at investigating the regulatory and molecular mechanism of epiberberine on HNSSC cell metastasis. The results showed that epiberberine inhibited the motility of Ca9-22 and FaDu cell lines at nontoxicity doses. Moreover, the epithelial-mesenchymal transition (EMT)-related proteins, vimentin, snail and slug, were found suppressing after epiberberine treatments. In addition, the JNK signalling cascade and the metalloproteinase 13 (MMP-13) expression were also found downregulated by epiberberine. In conclusion, the present study demonstrates that epiberberine suppresses cell migration and invasion by regulating the JNK pathway and MMP-13. These results suggest that epiberberine could be a potential antimetastatic agent in HNSCC cells.

Epiberberine regulates lipid synthesis through SHP (NR0B2) to improve non-alcoholic steatohepatitis.

Epiberberine (EPI), extracted from Rhizome Coptidis, has been shown to attenuate hyperlipidemia in vivo. Herein we have studied the mechanism by which EPI is active against non-alcoholic steatohepatitis (NASH) using, mice fed on a methionine- and choline-deficient (MCD) diet and HepG2 cells exposed to free fatty acids (FFA). We show that small heterodimer partner (SHP) protein is key in the regulation of lipid synthesis. In HepG2 cells and in the livers of MCD-fed mice, EPI elevated SHP levels, and this was accompanied by a reduction in sterol regulatory element-binding protein-1c (SREBP-1c) and FASN. Therefore, EPI reduced triglyceride (TG) accumulation in steatotic hepatocytes, even in HepG2 cells treated with siRNA-SHP, and also improved microbiota. Thus, EPI suppresses hepatic TG synthesis and ameliorates liver steatosis by upregulating SHP and inhibiting the SREBP1/FASN pathway, and improves gut microbiome.

Natural isoquinoline alkaloids: Pharmacological features and multi-target potential for complex diseases.

Complex diseases such as neurodegenerative disorders and cancer constitute a growing public health problem due to the rising incidence and lack in effective therapies. Since pharmacotherapy based on a single target has been insufficient for drug development in complex diseases, the emerging multi-target approach is a promising strategy for the search of new drug candidates. Plant-derived isoquinoline alkaloids comprise a vast source of multimodal agents with unique structural diversity, and variated range of pharmacological activities. This review offers an exhaustive compilation of the pharmacological relevance and multi-target potential of natural isoquinolines, emphasizing their features and promising activity in complex diseases such as Alzheimer, Parkinson, and Cancer. Selected examples were discussed in depth to illustrate the most relevant structural motifs and their possible relationship with the multimodal activity offering a comprehensive baseline in the search and optimization of isoquinoline scaffolds with polypharmacological potential for complex diseases.

A multi-herb-combined remedy to overcome hyper-inflammatory response by reprogramming transcription factor profile and shaping monocyte subsets.

Traditional Chinese multi-herb-combined prescriptions usually show better performance than a single agent since a group of effective compounds interfere multiple disease-relevant targets simultaneously. Huang-Lian-Jie-Du decoction is a remedy made of four herbs that are widely used to treat oral ulcers, gingivitis, and periodontitis. However, the active ingredients and underlying mechanisms are not clear. To address these questions, we prepared a water extract solution of Huang-Lian-Jie-Du decoction (HLJDD), called it as WEH (Water Extract Solution of HLJDD), and used it to treat LPS-induced systemic inflammation in mice. We observed that WEH attenuated inflammatory responses including reducing production of cytokines, chemokines and interferons (IFNs), further attenuating emergency myelopoiesis, and preventing mice septic lethality. Upon LPS stimulation, mice pretreated with WEH increased circulating Ly6C- patrolling and splenic Ly6C+ inflammatory monocytes. The acute myelopoiesis related transcriptional factor profile was rearranged by WEH. Mechanistically we confirmed that WEH interrupted LPS/TLR4/CD14 signaling-mediated downstream signaling pathways through its nine principal ingredients, which blocked LPS stimulated divergent signaling cascades, such as activation of NF-κB, p38 MAPK, and ERK1/2. We conclude that the old remedy blunts LPS-induced "danger" signal recognition and transduction process at multiple sites. To translate our findings into clinical applications, we refined the crude extract into a pure multicomponent drug by directly mixing these nine chemical entities, which completely reproduced the effect of protecting mice from lethal septic shock. Finally, we reduced a large number of compounds within a multi-herb water extract to seven-chemical combination that exhibited superior therapeutic efficacy compared with WEH.

Epiberberine ameliorated diabetic nephropathy by inactivating the angiotensinogen (Agt) to repress TGFß/Smad2 pathway.

BACKGROUND: Diabetic nephropathy (DN) is a severe microvascular complication of diabetes with prominent morbidity and mortality. At present, there are hardly any effective drugs to treat DN. Epiberberine (EPI), an isoquinoline alkaloid, has attracted considerable attention due to its anti-hyperglycemic, anti-hyperlipidemic, and anti-inflammatory functions. However, whether there is a protective effect of EPI on DN has not been reported. PURPOSE: The research was aimed to investigate the activities of EPI alleviating kidney damage in db/db mice and to explore its possible mechanisms. STUDY DESIGN: The db/db mice and high-glucose (HG) induced glomerular mesangial cells (GMCs) were used to explore the protective effect of EPI on DN in vivo and in vitro. METHODS: The changes in fasting blood glucose, metabolic index, renal function, and histopathological morphology in db/db mice were detected to evaluate the therapeutic effect of EPI. Then, renal transcriptome and molecular docking were used to screen the key targets. Subsequently, HG-induced GMCs through mimicing the pathological changes in DN were utilized to study the renal protective effects of EPI and its potential mechanism. RESULTS: The results in vivo showed that EPI administration for 8 weeks significantly alleviated diabetes-related metabolic disorders, improved renal functions, and relieved the histopathological abnormalities of renal tissue, especially renal fibrosis in db/db mice. The results in vitro showed that EPI inhibited the proliferation and induced the G2/M phase arrest of HG-induced GMCs. Moreover, a key gene Angiotensinogen (Agt) was screen out by the RNA-seq of kidney and molecular docking, and EPI reduced Agt, TGFß1, and Smad2 expression in vitro and in vivo. Noteworthy, Agt knockdown by siRNA significantly attenuated these beneficial efficacies exerted by EPI, indicating that Agt played a crucial role in the process of EPI improving DN. CONCLUSION: These findings suggested that EPI might be a potential drug for the treatment of DN dependent on the Agt-TGFß/Smad2 pathway.

Multifunctional epiberberine mediates multi-therapeutic effects.

Epiberberine, a natural protoberberine from Coptis chinensis Franch., is a potential alkaloid for the treatment of a variety of chronic diseases. The aim of this study is to summarize recent advances in the multiple and potential therapeutic effects of epiberberine. High-quality researches published in last two decades were retrieved from Web of science, ScienceDirect, PubMed and Springer with keywords namely 'epiberberine', 'protoberberine', 'coptis', 'huanglian', 'Coptidis rhizoma' and vital targets of some pathways in anti-adipogenesis, anti-dyslipidemia and anti-cancer activities. All the available research studies indicated that epiberberine is a multi-target small molecule with a low toxicity and exerts many activities including anti-adipogenesis via Akt and ERK pathways, anti-dyslipidemia via inhibition on cholesterol synthesis, anti-cancer via p53/Bax apoptosis pathway, anti-bacterial, improvement in diabetes and Alzheimer's disease. The present work will shed light on the direction for future investigations. Undoubtedly, C. chinensis and epiberberine are expected to exert beneficial effects in various diseases. However, there is a lack of evaluation of clinical applications and underlying molecular mechanisms of epiberberine in diabetes and dementia.

Natural alkaloid 8-oxo-epiberberine inhibited TGF-ß1-triggred epithelial-mesenchymal transition by interfering Smad3.

Epithelial-mesenchymal transition (EMT), the transition of epithelial cells into mesenchymal cells, plays important roles in the metastasis of solid tumors. 8-Oxo-epiberberine (OPB) is a natural alkaloid extracted from the roots of Coptis chinensis Franch. In this study, The effect and the underlying mechanism of OPB on EMT in a TGF-ß1-induced model and the inhibitory effect of OPB on lung metastasis were investigated. TGF-ß1-stimulated lung cancer cells were co-treated with OPB, the morphological changes were examined. The protein expression of EMT biomarkers E-cadherin and N-cadherin was determined by Western blotting and immunofluorescence. The transcription activity of smad2/3 promoter was analyzed by a luciferase reporter assay. The effect of OPB on cell migration, invasion, and adhesion was detected by wound-healing, adhesion, and transwell assays. The in vivo anti-metastatic effect of OPB was evaluated using a 4 T1 cell xenograft mouse model. Results showed that OPB significantly reversed TGF-ß1-triggered morphological changes, expression of EMT biomarkers, and migration, adhesion, and invasion. Furthermore, OPB suppressed TGF-ß1-induced Smad2/3 activation, Smad3 phosphorylation and nuclear translocation, and interaction of Smad3 with Smad4. Besides, OPB dramatically decreased the metastatic nodules in the lung without affecting the growth of primary tumors. In conclusion, OPB inhibited TGF-ß1-induced EMT possibly by interfering with Smad3. OPB might have therapeutic potentials for the treatment of metastatic cancers.

Effect of epiberberine from Coptis chinensis Franch on inhibition of tumor growth in MKN-45 xenograft mice.

BACKGROUND AND PURPOSE: Gastric cancer is one of the major malignancies worldwide. Epiberberine (EPI) is a major alkaloid from Coptis chinensis Franch and the antitumor property of EPI remains poorly understood. METHOD: The inhibition on gastric cancer cells was observed by MTT assays and colony formation experiments. The apoptosis, cell cycle, and reactive oxygen species (ROS) and mitochondrial membrane potential (ΔΨm) in gastric cancer cells were analyzed by Flow cytometry. The anti-tumor effect of EPI was evaluated with the MKN-45-beraring nude mice, and the potential mechanisms were explored by RNA-seq, qPCR, siRNA silencing and western blotting. RESULTS: EPI inhibited the proliferation of human gastric cancer cell lines MKN-45 (harboring wild-type p53) and HGC-27 (harboring mutant p53) in a dose dependent manner. EPI induced the apoptosis and cell cycle arrest in these two cell lines, of which MKN-45 cells are more sensitive to EPI than HGC-27 cells. Further experiments indicated that EPI induced the accumulation of ROS and decreased of ΔΨm in MKN-45 cells. The significant differentially expressed genes obtained by RNA-seq were distinctly enriched in the p53 signaling pathway. The apoptosis induced by EPI in MKN-45 cells would be effectively inhibited with the treatment of p53 siRNA and p53 inhibitor PFT-α. Western blotting demonstrated that EPI diminished the expression of Bcl-2 and XIAP, and increased those of p53, Bax, p21, p27, Cytochrome C and Cleaved-caspase 3. Animal experiments confirmed that EPI significantly alleviated tumor growth in MKN-45 xenograft mice via p53/Bax pathway. CONCLUSIONS: These data indicated that EPI could be a novel anti-tumor candidate against MKN-45-related gastric cancer via targeting p53-dependent mitochondria-associated pathway.

Natural protoberberine alkaloids, identified as potent selective LSD1 inhibitors, induce AML cell differentiation.

Natural protoberberine alkaloids were first identified and characterized as potent, selective and cellular active lysine specific demethylase 1 (LSD1) inhibitors. Due to our study, isoquinoline-based tetracyclic scaffold was identified as the key structural element for their anti-LSD1 activity, subtle changes of substituents attached to the core structure led to dramatic changes of the activity. Among these protoberberine alkaloids, epiberberine potently inhibited LSD1 (IC50 = 0.14 ± 0.01 µM) and was highly selective to LSD1 over MAO-A/B. Furthermore, epiberberine could induce the expression of CD86, CD11b and CD14 in THP-1 and HL-60 cells, confirming its cellular activity of inducing acute myeloid leukemia (AML) cells differentiation. Moreover, epiberberine prolonged the survival of THP-1 cells bearing mice and inhibited the growth of AML cells in vivo without obvious global toxicity. These findings give the potential application of epiberberine in AML treatment, and the isoquinoline-based tetracyclic scaffold could be used for further development of LSD1 inhibitors.

Molecular Recognition of the Hybrid-Type G-Quadruplexes in Human Telomeres.

G-quadruplex (G4) DNA secondary structures formed in human telomeres have been shown to inhibit cancer-specific telomerase and alternative lengthening of telomere (ALT) pathways. Thus, human telomeric G-quadruplexes are considered attractive targets for anticancer drugs. Human telomeric G-quadruplexes are structurally polymorphic and predominantly form two hybrid-type G-quadruplexes, namely hybrid-1 and hybrid-2, under physiologically relevant solution conditions. To date, only a handful solution structures are available for drug complexes of human telomeric G-quadruplexes. In this review, we will describe two recent solution structural studies from our labs. We use NMR spectroscopy to elucidate the solution structure of a 1:1 complex between a small molecule epiberberine and the hybrid-2 telomeric G-quadruplex, and the structures of 1:1 and 4:2 complexes between a small molecule Pt-tripod and the hybrid-1 telomeric G-quadruplex. Structural information of small molecule complexes can provide important information for understanding small molecule recognition of human telomeric G-quadruplexes and for structure-based rational drug design targeting human telomeric G-quadruplexes.

Study on changes of active components in Lianzhifan solution under different storage conditions / 中草药

Objective: To study on changes of active components in Lianzhifan solution (LZF) under different storage conditions, which may provide a reference for the application and quality improvement of the LZF. Methods: HPLC analysis was performed on Eclipse Agilent C18 column (250 mm × 4.6 mm, 5 μm). The gradient elution was performed by the mobile phase consisting of acetonitrile and 0.1% formic acid aqueous with the flow rate of 1.0 mL/min, the detection wavelength was set at 238 nm, and the column temperature was 25 ℃. A fingerprint analysis method for the chemical composition of LZF was established to analyze the change of main active components with time under sealed and unsealed storage conditions. Results: The precision, stability, repeatability and sample recovery of the HPLC fingerprint of LZF were all in accordance with the requirements, and can be used for the analysis of the chemical constituents of LZF. The similarity values of sample fingerprints and control fingerprints at different time points under both storage conditions were greater than 0.95; The nine chemical components in LZF were identified by using the external labeling method and spectral characteristic analysis. The content of alkaloids (columbamine, epiberberine, jatrorrhizine chloride, coptisine chloride, palmatine chloride, and berberine) did not change significantly under the two storage conditions. However, the content of the iridoids, genipin-1-β-D-gentiobioside and geniposide was significantly reduced, and the content of genipin was increased in the first 3 months but decreased after 3 months. It is speculated that genipin-1-β-D-gentiobioside and geniposide can be converted to genipin by the enzyme in solution, and genipin may be degraded by other enzymes produced by microorganisms. Conclusion: During the six-month storage period, LZF still has a convert tendency, which may be caused by the action of enzymes produced by microbes. In order to improve the quality consistency of LZF product, it is recommended to adopt more scientific method to judge the endpoint and it is better to inactivate enzyme and sterilize after the end of the fermentation processing.

The oral bioavailability, excretion and cytochrome P450 inhibition properties of epiberberine: an in vivo and in vitro evaluation.

Epiberberine (EPI) is a novel and potentially effective therapeutic and preventive agent for diabetes and cardiovascular disease. To evaluate its potential value for drug development, a specific, sensitive and robust high-performance liquid chromatography-tandem mass spectrometry assay for the determination of EPI in rat biological samples was established. This assay was used to study the pharmacokinetics, bioavailability and excretion of EPI in rats after oral administration. In addition, a cocktail method was used to compare the inhibition characteristics of EPI on cytochrome P450 (CYP450) isoforms in human liver microsomes (HLMs) and rat liver microsomes (RLMs). The results demonstrated that EPI was rapidly absorbed and metabolized after oral administration (10, 54 or 81 mg/kg) in rats, with Tmax of 0.37-0.42 h and T1/2 of 0.49-2.73 h. The Cmax and area under the curve values for EPI increased proportionally with the dose, and the oral absolute bioavailability was 14.46%. EPI was excreted mainly in bile and feces, and after its oral administration to rats, EPI was eliminated predominantly by the kidneys. A comparison of the current half-maximal inhibitory concentration and Ki values revealed that EPI demonstrated an obvious inhibitory effect on CYP2C9 and CYP2D6. Furthermore, its effect was stronger in HLM than in RLM, more likely to be a result of noncompetitive inhibition.

Anti-inflammatory mechanism of Scutellarlae Radix based on network pharmacology / 中草药

Objective: To explore the anti-inflammatory mechanism of Scutellarlae Radix (SR) by the network pharmacology. Methods: Firstly, the components in SR were searched through TCMSP database and screened with “Lipinski rule” and “Oral Bioavailability > 30%” rules. The targets of above components selected by PharmMapper web server and Cytoscape 3.4.0 was used to build a network between components and targets (component-target network, CTN). Secondly, “anti-inflammatory” targets was searched from Therapeutic Target Database (TTD) with keyword “anti-inflammatory”, and targets retrieved were used to build a protein-protein interaction (PPI) network based on the analysis by String database. To obtain anti-inflammatory targets of the active components in SR, the PPI network was fused with the CTN. Finally, the DAVID database was used to perform KEGG pathway enrichment analysis in order to explore the anti-inflammatory mechanism of SR. Results: Twenty-eight components in SR were obtained, including flavonoids such as baicalin, baicalein, wogonin, wogonoside, etc, alkaloids such as berberine, and epiberberine, and phenols such as dihydromyricetin, etc. Mitogen-activated protein kinase (MAPK14), tumor necrosis factor receptor superfamily 1A (TNFRSF1A), epidermal growth factor receptor (EGFR), and E-selectin (SELE) were the main targets of SR' anti-inflammatory effect. Salvigenin, epicatechin, and astragalusine mainly acted on MAPK14; Carthamidin acted on TNFRSF1A; Dihydromubutin A, 5,7,4’-trihydroxy-8-methoxyflavone, 5,7,4’-trihydroxy-8-methoxyflavanone, baicalin, and other components mainly acted on EGFR. There were 11 KEGG pathways, mainly related to TNF signaling pathways, MAPK signaling pathway, etc. Conclusion: There are three main anti-inflammatory mechanisms in SR, which can inhibit the production of inflammatory factors, inhibit the binding of inflammatory factors to their respective receptors, and block the initiation of inflammatory reactions.

RP-HPLC simultaneous determination of five isoquinoline alkaloid in Erhuang Xiaoyan tablets / 重庆医学

Objective To establish a method for determining five isoquinoline alkaloids (including berberine,jatrorrhizine,jatrorrhizind,coptisine and palmatine) in Erhuang Xiaoyan tablets simultaneously.Methods Determination by reversed phase high performance liquid chromatography (RP-HPLC).Column:YMC-Pack ODS-AM (4.6 mm× 250.0 mm,5 μm);mobile phase:elution with 0.1％ (v/v) formic acid aqueous solution-acetonitrile mobile phase gradient;flow rate:0.4 mL/min;injection volume:10 μL;detection wavelength:345 nm;column temperature:27 ℃.Results Five of isoquinoline alkaloids in Erhuang Xiaoyan tablets were separated perfectly.The good linear relationships were obtained in the following ranges,1.526 4-5.342 4μg (r=0.999 9) for berberine,0.403 2-1.411 2 μg (r=0.999 6) for palmatine,0.309 7-1.083 9 μg (r=0.999 8) for coptisine,0.111 2-0.389 2 μg (r=0.999 8) for jatrorrhizine and 0.162 2-0.567 7 μg (r=0.999 6) for epiberberine.The recoveries were 98.69％,98.66％,98.67％,98.67％ and 98.67％,respectively.Conclusion The method possesses high feasibility,strong specificity,high accuracy and good reproducibility,which can be used for the quality control of Erhuang Xiaoyan tablets.

Epiberberine, a natural protoberberine alkaloid, inhibits urease of Helicobacter pylori and jack bean: Susceptibility and mechanism.

In our previous study, Rhizoma Coptidis extract was found to exert more potent inhibitory effect than its major component berberine towards urease from Helicobacter pylori (HPU) and jack bean (JBU). In continuation of our work, the present study was designed to further comparatively investigate the urease inhibitory activities of five major protoberberine alkaloids in Rhizoma Coptidis, namely berberine, palmatine, coptisine, epiberberine, jateorhizine to identify the bioactive constituent, and illuminate the potential mechanism of action. Results indicated that the five protoberberine alkaloids acted as concentration-dependent inactivators of urease with IC50 values ranging between 3.0 and 5087µM for HPU and 2.3->10,000µM for JBU, respectively. Notably, epiberberine (EB) was found to be the most potent inhibitor against both ureases with IC50 values of 3.0±0.01µM for HPU and 2.3±0.01µM for JBU, which was more effective than the standard urease inhibitor, acetohydroxamic acid (83±0.01µM for HPU and 22±0.01µM for JBU, respectively). Further kinetic analysis revealed that the type of EB inhibition against HPU was slow-binding and uncompetitive, with Ki of 10.6±0.01µM, while slow-binding and competitive against JBU with Ki of 4.6±0.01µM. Addition of thiol reagents, such as l-cysteine, glutathione and dithiothreitol, significantly abolished the inhibition, while Ni2+ competitive inhibitors, boric acid and sodium fluoride, synergetically inhibited urease with EB, indicating the obligatory role of the active site sulfhydryl group for the inhibition. In addition, binding of EB with the urease proved to be reversible, as about 65% and 90% enzymatic activity of HPU and JBU, respectively, could be restored by dithiothreitol application. These findings highlighted the potential role of Rhizoma Coptidis protoberberine alkaloids, especially EB, as a lead urease inhibitor in the treatment of diseases associated with ureolytic bacteria. Thus, EB had good potential for further development into a promising therapeutic approach for the treatment of urease-related diseases.