New limonoids from Coptidis Rhizoma-Euodiae Fructus couple

Effect of the presence of berberine/curcumin on the binding of limonin to human serum albumin and antitumor activity in vitro

The competition among drugs for binding to plasma proteins is regarded as a pharmacokinetic drug interaction. Competition between antitumor agents and other drugs for plasma protein binding can alter the free concentration of the drug, potentially impacting its efficacy and increasing the risk of toxic side effects. Through a range of spectroscopic techniques, this study examined the interaction between limonin and human serum albumin (HSA) in the context of berberine (Ber) and curcumin (Cur) under physiological conditions to clarify the binding mechanisms of binary and ternary systems at the molecular level. As demonstrated by fluorescence quenching experiments, Static quenching was identified as the mechanism of interaction between HSA and limonin. The results of site competition experiments indicated that the binding site between limonin and HSA was site I, a result further supported by molecular docking simulations. Through the use of thermodynamic data calculations, it was determined that limonin forms a stable complex with HSA by establishing hydrogen bonds and van der Waals forces. Circular dichroism (CD) spectroscopy, three-dimensional (3D) fluorescence spectroscopy, and synchronous fluorescence spectroscopy (SFS) employed to validate the notion that limonin perturbed the microenvironment of amino acids and induced conformational changes in HSA. What's more, the presence of Ber or Cur was found to have further modified the alterations observed in the interaction between the original HSA-limonin binary system. In vitro cellular experiments showed that interaction with HSA reduced the antitumor activity of limonin. In contrast, adding Ber or Cur increased the inhibition rate of tumor cells. The coexistence of both Ber and Cur significantly diminished limonin's binding affinity to HSA. The current investigation enhances comprehension regarding the binding characteristics and interaction mechanisms involving limonin, Ber, Cur, and HSA. It explores the potential of HSA as a versatile drug carrier and furnishes theoretical underpinnings for co-administrative strategies.

Chemical constituents from the twigs with leaves of Tetradium trichotomum

Twelve compounds, comprising of four new ones, 6β,7α-limondiol (1) and ethyl 19-hydroxyisoobacunoate diosphenol (2), N-benzoyl 3-prenyltyramine (9) and 9-O-methyl integrifoliodiol (12), were isolated from the twigs with leaves of Tetradium trichotomum. The structures were elucidated by analysis of MS, NMR, and single-crystal X-ray diffraction. Compounds 1, 6, 8, 9 and 12 exhibited immunosuppressive activities in vitro against the proliferation of ConA-induced T lymphocytes and LPS-induced B cells.

Rutaecarpine Aggravates Acetaminophen-Induced Acute Liver Injury by Inducing CYP1A2

In this study, we investigated whether rutaecarpine could aggravate acetaminophen-induced acute liver damage in vivo and in vitro. CCK-8 and apoptosis assays were performed to verify the cytotoxicity of acetaminophen to L02 cells with or without rutaecarpine. The expression levels of the target proteins and genes were determined using Western blotting and qRT-PCR. The liver pathological changes were evaluated with hematoxylin and eosin staining, while the aspartate aminotransferase (AST) and alanine aminotransferase (AST) levels in plasma were measured to assess the liver damage. Our results revealed that pretreatment of the cell and mice with rutaecarpine significantly aggravated the acetaminophen-induced liver damage. Mechanistically, rutaecarpine induces the CYP1A2 protein, which accelerates the metabolism of acetaminophen to produce a toxic intermediate, N-acetyl-p-benzoquinone imine (NAPQI), leading to severe liver inflammation. Rutaecarpine exacerbated the liver damage by upregulating CYP1A2 and proinflammatory factors. These findings highlight the importance of carefully considering the dosage of rutaecarpine when combined with acetaminophen in drug design and preclinical trials.

Mechanism underlying the effect of Pulsatilla decoction in hepatocellular carcinoma treatment: a network pharmacology and in vitro analysis

BACKGROUND

Currently, hepatocellular carcinoma (HCC) is associated with a poor prognosis. Moreover, there exist limited strategies for treating HCC. Pulsatilla decoction (PD), a traditional Chinese medicine formula, has been used to treat inflammatory bowel disease and several cancer types. Accordingly, we explored the mechanism of PD in HCC treatment via network pharmacology and in vitro experiments.

METHODS

Online databases were searched for gene data, active components, and potential target genes associated with HCC development. Subsequently, bioinformatics analysis was performed using protein-protein interaction and Network Construction and Kyoto Encyclopedia of Genes and Genomes (KEGG) to screen for potential anticancer components and therapeutic targets of PD. Finally, the effect of PD on HCC was further verified by in vitro experiments.

RESULTS

Network pharmacological analysis revealed that 65 compounds and 180 possible target genes were associated with the effect of PD on HCC. These included PI3K, AKT, NF-κB, FOS, and NFKBIA. KEGG analysis demonstrated that PD exerted its effect on HCC mainly via the PI3K-AKT, IL-17, and TNF signaling pathways. Cell viability and cell cycle experiments revealed that PD could significantly inhibit cancer cell proliferation and kill HCC cells by inducing apoptosis. Furthermore, western blotting confirmed that apoptosis was mediated primarily via the PI3K-AKT, IL-17, and TNF signaling pathways.

CONCLUSION

To the best of our knowledge, this is the first study to elucidate the molecular mechanism and potential targets of PD in the treatment of HCC using network pharmacology.

Chromatographic and mass spectrometric technologies for chemical analysis of Euodiae fructus: A review

INTRODUCTION

Euodiae fructus, also known as Evodiae fructus, is a popular Chinese herbal medicine derived from the dried, nearly ripe fruits of Tetradium ruticarpum (A. Juss.) T. G. Hartley. The main bioactive constituents of Euodiae fructus are alkaloids, limonoids, flavonoids, and anthraquinones. The contents of these compounds vary greatly between different plant species, geographic locations, and harvest times, which thus affect the therapeutic effects.

OBJECTIVES

We aimed to summarize the chromatographic and mass spectrometric technologies applied for chemical analysis and quality evaluation of Euodiae fructus. Moreover, we aimed to emphasize the diverse soft ionization techniques and mass analyzers of LC-MS methods for assessment of Euodiae fructus.

METHODOLOGY

A literature study was carried out by retrieving articles published between January 1988 and December 2021 from well-known databases, including PubMed, ASC, Elsevier, ScienceDirect, J·STAGE, Thieme, Taylor & Francis, Springer Link, Wiley Online Library, and CNKI. The chemical analysis methods were described in several categories in accordance with the used analytical techniques, including thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), high-performance liquid chromatography-mass spectrometry (HPLC-MS), gas chromatography-mass spectrometry (GC-MS), capillary electrophoresis (CE), and counter-current chromatography (CCC).

RESULTS

This review systematically summarizes the achievements in chemical analysis and quality evaluation of Euodiae fructus published in over three decades, covering the various chromatographic and mass spectrometric technologies applied for identification and quantification of phytochemical constituents.

CONCLUSION

The summary serves as an important basis for future phytochemical research and implementation of quality control methods in order to ensure the efficacy and safety of Euodiae fructus.

New limonoids and quinolone alkaloids with cytotoxic and anti-platelet aggregation activities from Evodia rutaecarpa (Juss.) Benth

One new limonoid, named 19-hydroxy methyl isoobacunoate diosphenol (1); one new degraded limonoid, named 9α-methoxyl dictamdiol (9); two new quinolone alkaloids, 1-methyl-3-[(7E,9E,12Z)-7,9,12-pentadecadienyl]-4(1H)-quinolone (11) and 1-methyl-3-[(7E,9E,11E)-7,9,11-pentadecadienyl]-4(1H)-quinolone (12), along with eight known compounds, evodol (2), 7β-acetoxy-5-epilimonin (3), rutaevine (4), 6β-acetoxy-5-epilimonin (5), limonin (6), obacunone (7), clauemargine L (8), hiiranlactone E (10) were isolated from the fruits of Evodia rutaecarpa (Juss.) Benth.. Structures of the four new compounds were elucidated on the basis of extensive spectroscopic techniques, including 1D and 2D NMR techniques. Compounds 3, 5, 9, 11 and 12 showed obviously cytotoxic activity against six human tumor lines, while compounds 11, 12 displayed anti-platelet aggregation induced by ADP at 50 μM and 100 μM.

Limonin: A Review of Its Pharmacology, Toxicity, and Pharmacokinetics

Limonin is a natural tetracyclic triterpenoid compound, which widely exists in Euodia rutaecarpa (Juss.) Benth., Phellodendron chinense Schneid., and Coptis chinensis Franch. Its extensive pharmacological effects have attracted considerable attention in recent years. However, there is no systematic review focusing on the pharmacology, toxicity, and pharmacokinetics of limonin. Therefore, this review aimed to provide the latest information on the pharmacology, toxicity, and pharmacokinetics of limonin, exploring the therapeutic potential of this compound and looking for ways to improve efficacy and bioavailability. Limonin has a wide spectrum of pharmacological effects, including anti-cancer, anti-inflammatory and analgesic, anti-bacterial and anti-virus, anti-oxidation, liver protection properties. However, limonin has also been shown to lead to hepatotoxicity, renal toxicity, and genetic damage. Moreover, limonin also has complex impacts on hepatic metabolic enzyme. Pharmacokinetic studies have demonstrated that limonin has poor bioavailability, and the reduction, hydrolysis, and methylation are the main metabolic pathways of limonin. We also found that the position and group of the substituents of limonin are key in affecting pharmacological activity and bioavailability. However, some issues still exist, such as the mechanism of antioxidant activity of limonin not being clear. In addition, there are few studies on the toxicity mechanism of limonin, and the effects of limonin concentration on pharmacological effects and toxicity are not clear, and no researchers have reported any ways in which to reduce the toxicity of limonin. Therefore, future research directions include the mechanism of antioxidant activity of limonin, how the concentration of limonin affects pharmacological effects and toxicity, finding ways to reduce the toxicity of limonin, and structural modification of limonin—one of the key methods necessary to enhance pharmacological activity and bioavailability.

Genus Tetradium L.: A comprehensive review on traditional uses, phytochemistry, and pharmacological activities

ETHNOPHARMACOLOGICAL RELEVANCE

The dried fruit of Tetradium ruticarpum is frequently utilized as a common traditional medicine in China, Japan and Korea. It has been widely used for the treatment of various diseases such as headache, menorrhalgia, dermatophytosis, celialgia, emesis and aphtha and so on.

AIM OF THIS REVIEW

Despite the wide biological activities of Tetradium plants, there is no current review summarizing medicinal properties of the genus of plants; thus, this review aims to systematically summarize studies on botanical characteristics, traditional uses, phytochemical ingredients, quality control, pharmacokinetics, pharmacological activities and toxicity of Tetradium species to demonstrate their therapeutic capacity.

MATERIALS AND METHODS

Information and materials related to Tetradium species were obtained from scientific databases such as Google Scholar, Wikipedia, Web of Science, PubMed, ScienceDirect, ACS Publications, SciFinder. Information was also gathered from International Plant Names Index, Global Biodiversity Information Facility, Chinese Pharmacopoeia and Traditional Chinese Medicine classics, etc. All studies of this genus were included in this review until July 2018.

RESULTS

Tetradium is widely assessed regarding its phytochemistry and biological activities. Approximately 131 chemical compounds, including alkaloids, saponins, phenols and other compounds, have been isolated from Tetradium plants. Among these components, alkaloid evodiamine is the most representative active ingredients of Tetradium plants. These compounds isolated from Tetradium plants exhibit a wide range of biological activities in vitro and in vivo including antitumor, antibacterial, anti-inflammatory, insecticide, cardioprotective and lipid-lowering, treating CNS disorders, digestive system regulation and endocrine system improving activities. Furthermore, alkaloids could be used as markers for quality identification and evaluation of medicinal materials and their preparations. Information on evaluating the safety and pharmacokinetics of Tetradium often focuses on the alkaloids, thus further study and clinical data are required to enable the drug safety of the utilization of Tetradium plants.

CONCLUSIONS

Phytochemical and pharmacological studies of Tetradium plants have proved Tetradium plants are important medicinal herb resource. However, well-designed randomized clinical trials are necessary to confirm the therapeutic benefits of this genus in clinical settings.

Triterpenoids

Covering 2014. Previous review: Nat. Prod. Rep., 2017, 34, 90-122 This review covers the isolation and structure determination of triterpenoids reported during 2014 including squalene derivatives, lanostanes, holostanes, cycloartanes, cucurbitanes, dammaranes, euphanes, tirucallanes, tetranortriterpenoids, quassinoids, lupanes, oleananes, friedelanes, ursanes, hopanes, serratanes, isomalabaricanes and saponins; 374 references are cited.

A New Quinolone Alkaloid with Cytotoxic Activity from the Fruits of Euodia Rutaecarpa

A new quinolone alkaloid, 1-methyl-2-[( Z)-1-undecenyl]–4( 1H)-quinolone (1), together with two known quinolone alkaloids (2–3), and three known limonoids (4–6), were isolated from the fruits of Euodia rutaecarpa (Juss.) Benth.. Their chemical structure was determined by UV, MS, NMR and comparison with literatures. Bioassay results indicated that compound 1 had moderate cytotoxicity against tumor cell lines Lovo, MDA-MB-231 and HeLa with IC50 values of 6.72, 14.20 and 13.05 μM, respectively.

Pharmacokinetics Studies of 12 Alkaloids in Rat Plasma after Oral Administration of Zuojin and Fan-Zuojin Formulas

Zuojin formula (ZJ) is a traditional Chinese medicine (TCM) prescription consisted of Coptidis Rhizoma (CR) and Euodiae Fructus (EF), and has been used to treat gastrointestinal (GI) disease for more than 700 years. Fan-Zuojin formula (FZJ) is a related TCM prescription also consisted of CR and EF with the opposite proportion. In recent years, ZJ was getting more attention for its antitumor potential, but the indeterminate pharmacokinetic (PK) behavior restricted its clinical applications, and the PK differences between ZJ and FZJ were also largely unknown. Consequently it is necessary to carry out a full-scale PK study to demonstrate the physiological disposition of ZJ, as well as the comparative PK study between ZJ and FZJ to illustrate the compatibility dose effects. Therefore a liquid chromatographic–tandem mass spectrometry (LC–MS/MS) method was established and validated for the determinations of coptisine, epiberberine, palmatine, berberine, 8-oxocoptisine, 8-oxoepiberberine, noroxyhydrastinine, corydaldine, dehydroevodiamine, evodiamine, wuchuyuamide-I, and evocarpine in rat plasma. PK characteristics of 12 alkaloids after oral administration of ZJ and FZJ were compared, and the result was analyzed and discussed with the help of an in silico study. Then an integrated PK study was carried out with the AUC-based weighting method and the total drug concentration method. The established method has been successfully applied to reveal the PK profiles of the 12 alkaloids in rat plasma after oral administration of ZJ and FZJ. The results showed that: (1) double peaks were observed in the plasma concentration-time (C–T) curves of the alkaloids after ZJ administration; but the C–T curves approximately matched the two-compartment model after FZJ administration; (2) There were wide variations in the absorption levels of these alkaloids; and even for a certain alkaloid, the dose modified systemic exposure levels and elimination rate also varied significantly after administration of ZJ and FZJ extracts. The results could be interpreted as follows: firstly, inhibition effect on GI motility caused by the high content CR alkaloids (especially berberine) in ZJ could delay the T_max, and increase the absorption and systemic exposure levels of the other alkaloids, and also lead to the double peak phenomenon of these alkaloids. However, for quaternary protoberberine alkaloids (QPA), double peaks were primarily caused by the different Ka value in two intestinal absorption sites; Secondly, absorption was the major obstacle to the systemic exposure level of the alkaloids from CR and EF. In silico and PK studies suggested that the absorption of these alkaloids, except QPAs, mainly depended on their solubility rather than permeability; Thirdly, EF could promote the absorption and accelerate the elimination of QPAs, and had a greater influence on the former than the latter. At last the integrated PK analysis suggested that berberine and dehydroevodiamine could be regarded as the representative components to reflect the PK behaviors of CR and EF alkaloids after administration of ZJ and FZJ. In conclusion, the absorption, elimination and systemic exposure level of these alkaloids were mainly influenced by the proportion of EF and CR, the pharmacological effect on GI motility, and the physicochemical property of these alkaloids. These findings would be helpful for a better understanding of the activities and clinical applications of ZJ, FZJ and other related TCM prescriptions.

Limonoids with neuroprotective activity from the stems of Clausena emarginata

Two new limonoids, clauemargines M-N (1-2), together with five known compounds (3-7), were isolated from the stems of Clausena emarginata, and compounds 6 and 7 were gained from this plant for the first time. Their structures were established and elucidated on the basis of comprehensive spectroscopic analysis. The absolute configurations of 1-2 were further determined by the octant rule of saturated cyclic ketone. Compounds 1, 2, 4, and 5 showed moderate neuroprotective effects against L-glutamic acid-induced cellular damage in human neuroblastoma SK-N-SH cells at 10 μM.