Inhibition of DNA topoisomerases I and II and cytotoxicity of compounds from Ulmus davidiana var. japonica

Catechin and flavonoid glycosides from the Ulmus genus: Exploring their nutritional pharmacology and therapeutic potential in osteoporosis and inflammatory conditions

This review investigates the therapeutic effects of Ulmus species extracts, traditionally used as tea ingredients in East Asia, on bone health and inflammatory conditions. Through the analysis of 9757 studies, narrowing down to 56 pertinent ones, we evaluated the safety and efficacy of Ulmus extracts. The focus was on catechin glycosides (CG) and flavonoid glycosides (FG), key compounds identified for their potential benefits. The research highlights the extracts' role in enhancing bone mineral density (BMD) by stimulating osteoblast activity and suppressing osteoclast differentiation, suggesting a protective effect against osteoporosis. Furthermore, the extracts demonstrated significant anti-inflammatory properties by modulating inflammatory markers and pathways. The findings confirm the historical use of Ulmus extracts in East Asia for health benefits and recommend further exploration into functional foods and nutraceuticals. The review calls for more rigorous research, including clinical trials, to establish optimal use and integration into modern health solutions. It underscores the potential of Ulmus extracts in promoting bone health and managing inflammation, advocating for a bridge between traditional practices and contemporary scientific validation. In conclusion, Ulmus extracts, a material long consumed as tea ingredients in East Asia, exhibit significant potential for improving bone health and reducing inflammation. This review calls for additional research to explore their full therapeutic capabilities, emphasizing the need for optimized extraction methods and clinical trials. It reinforces the importance of bridging traditional knowledge with contemporary scientific approaches to health and dietary solutions, promoting overall wellness.

Anatomical and Chemical Characterization of Ulmus Species from South Korea

Ulmus species (Ulmaceae) are large deciduous trees distributed throughout Korea. Although their root and stem bark have been used to treat gastrointestinal diseases and wounds in folk medicine, commercial products are consumed without any standardization. Therefore, we examined anatomical and chemical differences among five Ulmus species in South Korea. Transverse sections of leaf, stem, and root barks were examined under a microscope to elucidate anatomical differences. Stem and root bark exhibited characteristic medullary ray and secretary canal size. Leaf surface, petiole, and midrib exhibited characteristic inner morphologies including stomatal size, parenchyma, and epidermal cell diameter, as well as ratio of vascular bundle thickness to diameter among the samples. Orthogonal projections to latent structures discriminant analysis of anatomical data efficiently differentiated the five species. To evaluate chemical differences among the five species, we quantified (-)-catechin, (-)-catechin-7-O-β-D-apiofuranoside, (-)-catechin-7-O-α-L-rhamnopyranoside, (-)-catechin-7-O-β-D-xylopyranoside, (-)-catechin-7-O-β-D-glucopyranoside, and (-)-catechin-5-O-β-D-apiofuranoside using high-performance liquid chromatography with a diode-array detector. (-)-Catechin-7-O-β-D-apiofuranoside content was the highest among all compounds in all species, and (-)-catechin-7-O-α-L-rhamnopyranoside content was characteristically the highest in Ulmus parvifolia among the five species. Overall, the Ulmus species tested was able to be clearly distinguished on the basis of anatomy and chemical composition, which may be used as scientific criteria for appropriate identification and standard establishment for commercialization of these species

Bakuchiol, main component of root bark of Ulmus davidiana var. japonica, inhibits TGF-β-induced in vitro EMT and in vivo metastasis

Cancer is a second leading cause of death worldwide, and metastasis is the major cause of cancer-related mortality. The epithelial-mesenchymal transition (EMT), known as phenotypic change from epithelial cells to mesenchymal cells, is a crucial biological process during development. However, inappropriate activation of EMT contributes to tumor progression and promoting metastasis; therefore, inhibiting EMT is considered a promising strategy for developing drugs that can treat or prevent cancer. In the present study, we investigated the anti-cancer effect of bakuchiol (BC), a main component of Ulmus davidiana var. japonica, in human cancer cells using A549, HT29 and MCF7 cells. In MTT and colony forming assay, BC exerted cytotoxicity activity against cancer cells and inhibited proliferation of these cells. Anti-metastatic effects by BC were further confirmed by observing decreased migration and invasion in TGF-β-induced cancer cells after BC treatment. Furthermore, BC treatment resulted in increase of E-cadherin expression and decrease of Snail level in Western blotting and immunofluorescence analysis, supporting its anti-metastatic activity. In addition, BC inhibited lung metastasis of tail vein injected human cancer cells in animal model. These findings suggest that BC inhibits migration and invasion of cancers by suppressing EMT and in vivo metastasis, thereby may be a potential therapeutic agent for treating cancers.

Anti-Obesity and Lipid Metabolism Effects of Ulmus davidiana var. japonica in Mice Fed a High-Fat Diet

The root bark of Ulmus davidiana var. japonica (Japanese elm) is used in Korea and other East Asian countries as a traditional herbal remedy to treat a variety of inflammatory diseases and ailments such as edema, gastric cancer and mastitis. For this study, we investigated the lipid metabolism and anti-obesity efficacy of ethyl alcohol extract of Ulmus davidiana var. japonica root bark (UDE). First, HPLC was performed to quantify the level of (+)-catechin, the active ingredient of UDE. In the following experiments, cultured 3T3-L1 pre-adipocytes and high-fat diet (HFD)-fed murine model were studied for anti-obesity efficacy by testing the lipid metabolism effects of UDE and (+)-catechin. In the test using 3T3-L1 pre-adipocytes, treatment with UDE inhibited adipocyte differentiation and significantly reduced the production of adipogenic genes and transcription factors PPARγ, C/EBPα and SREBP-1c. HFD-fed, obese mice were administered with UDE (200 mg/kg per day) and (+)-catechin (30 mg/kg per day) by oral gavage for 4 weeks. Weight gain, epididymal and abdominal adipose tissue mass were significantly reduced, and a change in adipocyte size was observed in the UDE and (+)-catechin treatment groups compared to the untreated control group (***p < 0.001). Significantly lower total cholesterol and triglyceride levels were detected in UDE-treated HFD mice compared to the control, revealing the efficacy of UDE. In addition, it was found that lipid accumulation in hepatocytes was also significantly reduced after administration of UDE. These results suggest that UDE has significant anti-obesity and lipid metabolism effects through inhibition of adipocyte differentiation and adipogenesis.

Ulmusakidian, a new coumarin glycoside and antifungal phenolic compounds from the root bark of Ulmus davidiana var. japonica

Bioactivity-driven LC/MS-based phytochemical analysis of the root bark extract of Ulmus davidiana var. japonica led to the isolation of 10 compounds including a new coumarin glycoside derivative, ulmusakidian (1). The structure of the new compound was elucidated using extensive spectroscopic analyses via 1D and 2D NMR spectroscopic data interpretations, HR-ESIMS, and chemical transformation. The isolated compounds 1-10 were tested for their antifungal activity against human fungal pathogens Cryptococcus neoformans and Candida albicans. Compounds 9 and 10 showed antifungal activity against C. neoformans, with the lowest minimal inhibitory concentration (MIC) of 12.5-25.0 µg/mL, whereas none of the compounds showed antifungal activity against C. albicans.

In vitro and in silico assessment of DNA interaction, topoisomerase I and II inhibition properties of chrysosplenetin

Chrysosplenetin is a methoxyflavone with reported anti-cancer effect. We tested its cytotoxic effect on the MCF-7 breast cancer cell line, and determined its effect on DNA intercalation and on the activity of topoisomerases I and II. The compound inhibited proliferation MCF-7 with an IC₅₀ value of 0.29 μM. Chrysosplenetin did not initiate plasmid DNA cleavage but, in a concentration-dependent manner, protected plasmid DNA against damage induced by Fenton reagents. Furthermore, it possessed dual Topoisomerase I and II inhibitory properties. Especially, it inhibited topoisomerase II by 83-96% between the range 12.5-100 μM. In the light of these experimental findings, molecular docking studies were performed to understand binding mode, interactions and affinity of chrysosplenetin with DNA, and with topoisomerases I and II. These studies showed that of 4-chromone core and the hydroxyl and methoxy groups important for both intercalation with DNA and topoisomerase I and II inhibition.

Analysis of plant-derived phytochemicals as anti-cancer agents targeting cyclin dependent kinase-2, human topoisomerase IIa and vascular endothelial growth factor receptor-2

Cancer is caused by a variety of pathways, involving numerous types of enzymes. Among them three enzymes i.e. Cyclin-dependent kinase-2 (CDK-2), Human topoisomerase IIα, and Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2) are three of the most common enzymes that are involved in the cancer development. Although many chemical drugs are already available in the market for cancer treatment, plant sources are known to contain a wide variety of agents that are proved to possess potential anticancer activity. In this experiment, total thirty phytochemicals were analyzed against the mentioned three enzymes using different tools of bioinformatics and in silico biology like molecular docking study, drug likeness property experiment, ADME/T test, PASS prediction, and P450 site of metabolism prediction as well as DFT calculation to determine the three best ligands among them that have the capability to inhibit the mentioned enzymes. From the experiment, Epigallocatechin gallate was found to be the best ligand to inhibit CDK-2, Daidzein showed the best inhibitory activities towards the Human topoisomerase IIα, and Quercetin was predicted to be the best agent against VEGFR-2. They were also predicted to be quite safe and effective agents to treat cancer. However, more in vivo and in vitro analyses are required to finally confirm their safety and efficacy in this regard.

(-)-Catechin-7-O-β-d-Apiofuranoside Inhibits Hepatic Stellate Cell Activation by Suppressing the STAT3 Signaling Pathway

Hepatic fibrosis is characterized by the abnormal deposition of extracellular matrix (ECM) proteins. During hepatic fibrogenesis, hepatic stellate cell (HSC) activation followed by chronic injuries is considered a key event in fibrogenesis, and activated HSCs are known to comprise approximately 90% of ECM-producing myofibroblasts. Here, we demonstrated that (–)-catechin-7-O-β-d-apiofuranoside (C7A) significantly inhibited HSC activation via blocking the signal transducer and activator of transcription 3 (STAT3) signaling pathway. This is the first study to show the hepatic protective effects of C7A with possible mechanisms in vitro and in vivo. In our bioactivity screening, we figured out that the EtOH extract of Ulmus davidiana var. japonica root barks, which have been used as a Korean traditional medicine, inhibited collagen synthesis in HSCs. Four catechins isolated from the EtOAc fraction of the EtOH extract were compared with each other in terms of reduction in collagen, which is considered as a marker of hepatic protective effects, and C7A showed the strongest inhibitory effects on HSC activation in protein and qPCR analyses. As a possible mechanism, we investigated the effects of C7A on the STAT3 signaling pathway, which is known to activate HSCs. We found that C7A inhibited phosphorylation of STAT3 and translocation of STAT3 to nucleus. C7A also inhibited expressions of MMP-2 and MMP-9, which are downstream genes of STAT3 signaling. Anti-fibrotic effects of C7A were evaluated in a thioacetamide (TAA)-induced liver fibrosis model, which indicated that C7A significantly inhibited ECM deposition through inhibiting STAT3 signaling. C7A decreased serum levels of aspartate amino transferase and alanine transaminase, which were markedly increased by TAA injection. Moreover, ECM-associated proteins and mRNA expression were strongly suppressed by C7A. Our study provides the experimental evidence that C7A has inhibitory effects on HSC activation after live injury and has preventive and therapeutic potentials for the management of hepatic fibrosis.

Chemical constituents of the root bark of Ulmus davidiana var. japonica and their potential biological activities

The root bark of Ulmus davidiana var. japonica (Ulmaceae), commonly known as yugeunpi, has been used as a traditional Korean medicine for the treatment of gastroenteric and inflammatory disorders. As part of continuing projects to discover bioactive natural products from traditional medicinal plants with pharmacological potential, phytochemical investigation of the root bark of this plant was carried out. This led to the successful isolation of a new chromane derivative (1) and 22 known compounds: catechin derivatives (2-5), megastigmane glycoside (6), dihydrochalcone glycosides (7 and 8), flavanone glycosides (9 and 10), coumarins (11 and 12), lignan derivatives (13-17), and phenolic compounds (18-23). The structure of the new compound (1) was determined with 1D and 2D NMR spectroscopy and HR-ESIMS, and its absolute configurations were achieved by chemical reactions and the gauge-including atomic orbital (GIAO) NMR chemical shifts calculations. All the isolated compounds were evaluated for their potential biological activities including neuro-protective, anti-neuroinflammatory, and anti-Helicobacter pylori activities. Among the isolates, compounds 1, 8, and 20 displayed stronger potency by causing a greater increase in the production and the activity of nerve growth factor (NGF) in C6 glioma cells (147.04 ± 4.87, 206.27 ± 6.70, and 143.70 ± 0.88%, respectively), whereas compounds 11, 14, and 19 inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated murine microglial cells (IC₅₀ of 18.72, 12.31, and, 21.40 µM, respectively). In addition, compounds 1, 11, 18, and 20 showed anti-H. pylori activity with MIC values of 25 or 50 µM against two strains of H. pylori 51 and 43504. These findings provide scientific evidence that supports the traditional usage of U. davidiana var. japonica root bark in the treatment of gastroenteric and inflammatory disorders.

A comprehensive review of topoisomerase inhibitors as anticancer agents in the past decade

The topoisomerase enzymes play an important role in DNA metabolism, and searching for enzyme inhibitors is an important target in the search for new anticancer drugs. Discovery of new anticancer chemotherapeutical capable of inhibiting topoisomerase enzymes is highlighted in anticancer research. Therefore, biologists, organic chemists and medicinal chemists all around the world have been identifying, designing, synthesizing and evaluating a variety of novel bioactive molecules targeting topoisomerase. This review summarizes types of topoisomerase inhibitors in the past decade, and divides them into nine classes by structural characteristics, including N-heterocycles compounds, quinone derivatives, flavonoids derivatives, coumarin derivatives, lignan derivatives, polyphenol derivatives, diterpenes derivatives, fatty acids derivatives, and metal complexes. Then we discussed the application prospect and development of these anticancer compounds, as well as concluded parts of their structural-activity relationships. We believe this review would be invaluable in helping to further search potential topoisomerase inhibition as antitumor agent in clinical usage.

Antimicrobial peptide based magnetic recognition elements and Au@Ag-GO SERS tags with stable internal standards: a three in one biosensor for isolation, discrimination and killing of multiple bacteria in whole blood

A SERS based biosensor has been developed for isolation, detection and killing of multiple bacterial pathogens.

In this study, a new biosensor based on a sandwich structure has been developed for the isolation and detection of multiple bacterial pathogens via magnetic separation and SERS tags. This novel assay relies on antimicrobial peptide (AMP) functionalized magnetic nanoparticles as “capturing” probes for bacteria isolation and gold coated silver decorated graphene oxide (Au@Ag-GO) nanocomposites modified with 4-mercaptophenylboronic acid (4-MPBA) as SERS tags. When different kinds of bacterial pathogens are combined with the SERS tags, the “fingerprints” of 4-MPBA show corresponding changes due to the recognition interaction between 4-MPBA and different kinds of bacterial cell wall. Compared with the label-free SERS detection of bacteria, 4-MPBA here can be used as an internal standard (IS) to correct the SERS intensities with high reproducibility, as well as a Raman signal reporter to enhance the sensitivity and amplify the differences among the bacterial “fingerprints”. Thus, three bacterial pathogens (Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa) were successfully isolated and detected, with the lowest concentration for each of the strains detected at just 10¹ colony forming units per mL (CFU mL^–1). According to the changes in the “fingerprints” of 4-MPBA, three bacterial strains were successfully discriminated using discriminant analysis (DA). In addition, the AMP modified Fe₃O₄NPs feature high antibacterial activities, and can act as antibacterial agents with low cellular toxicology in the long-term storage of blood for future safe blood transfusion applications. More importantly, this novel method can be applied in the detection of bacteria from clinical patients who are infected with bacteria. In the validation analysis, 97.3% of the real blood samples (39 patients) could be classified effectively (only one patient infected with E. coli was misclassified). The multifunctional biosensor presented here allows for the simultaneous isolation, discrimination and killing of bacteria, suggesting its high potential for clinical diagnosis and safe blood transfusions.

DNA Topoisomerase Inhibitory Activity of Constituents from the Fruits of Illicium verum

Three new compounds, a sesquilignan (1) and two glucosylated phenylpropanoids (2, 3), and seven known compounds (4-10), were isolated from the fruits of Illicium verum HOOK. FIL. (Illiciaceae). The structures of 1-3 were determined based on one and two dimensional (1D- and 2D-) NMR data and electronic circular dichroism (ECD) spectra analyses. Compounds 3, 5, 6, and 8-10 exhibited potent inhibitory activities against topoisomerase II with IC₅₀ values of 54.6, 25.5, 17.9, 12.1, 0.3 and 1.0 µM, respectively, compared to etoposide, the positive control, with an IC₅₀ of 43.8 µM.

LC/ESI-MS/MS profiling of Ulmus parvifolia extracts and evaluation of its anti-inflammatory, cytotoxic, and antioxidant activities

In this study, a comparative liquid chromatography/mass spectroscopy (LC/ESI-MS/MS) profiling of different fractions of Ulmus parvifolia leaves and stems was performed. Identification of compounds was based on comparing the mass spectrometric information obtained including m/z values and individual compound fragmentation pattern to tandem mass spectral library search and literature data. Eleven compounds were tentatively identified in the different analyzed fractions. One of the major constituents of this plant was isolated and identified as Icariside E4 [dihydro-dehydro-diconiferyl alcohol-4-O-α-L-rhamnopyranoside] (5). The evaluation of anti-inflammatory activity of the total methanolic extract using nitric oxide inhibition on LPS-stimulated RAW 264.7 cells model strong anti-inflammatory activity with 17.5% inhibition of nitric oxide production versus 10% inhibition for dexamethasone. The cytotoxic activity of the methanolic extract and Icariside E4 was evaluated against four types of human cell lines using MTT assay. Icariside E4 showed cytotoxic effect against Hep-G2, MCF-7, and CACO-2 cell lines compared to a negligible activity for the total extract. The same extract showed a moderate antioxidant activity with SC50=362.5 μg/mL.

In Vitro Evaluation of the Antimicrobial Ability and Cytotoxicity on Two Melanoma Cell Lines of a Benzylamide Derivative of Maslinic Acid

Maslinic acid is a pentacyclic triterpene extracted from olives that has been systematically reported to exert several therapeutic effects, such as antitumoral, antidiabetic, antioxidant, anti-inflammatory, antiparasitic, and antiviral properties. Recently, new derivatives of maslinic acid have been obtained and expanded the spectrum of biological activities and improved the existing ones. The present study was meant to perform the in vitro assessment of the (i) cytotoxic effects of a benzylamide derivative of maslinic acid ("EM2") (benzyl (2α, 3β) 2,3-diacetoxy-olean-12-en-28-amide) on B164A5 murine melanoma and A375 human malignant melanoma cell lines and the (ii) antimicrobial activity of the compound on several bacterial strains, respectively. We obtained a dose-dependent cytotoxic effect of EM2 that was particularly relevant to the murine cell line. As on the antibacterial activity, EM2 was tested on 10 bacterial strains Bacillus cereus, Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, Enterococcus faecalis, Escherichia coli, Yersinia enterocolitica, Klebsiella pneumoniae, Proteus mirabilis, and Pseudomonas aeruginosa and one fungus Candida albicans. A significant antimicrobial effect was recorded for Streptococcus pyogenes and Staphylococcus aureus.

Multiple shoot cultures of Ophiorrhiza rugosa var. decumbens Deb and Mondal--a viable renewable source for the continuous production of bioactive Camptotheca alkaloids apart from stems of the parent plant of Nothapodytes foetida (Wight) Sleumer

Camptotheca alkaloids were isolated from multiple shoot cultures of O. decumbens (0.056% dry weight) and stems of N. foetida. The cytotoxicity of the extracts and products were tested in a panel of five cell lines. Crude extract from O. decumbens (Cr-Od) and N. foetida (Cr-Nf) showed more potent cytotoxic activity as compared to the isolated camptothecin from O. decumbens (CPT-Od) and N. foetida (CPT-Nf). CPT isolated from shoot cultures contained biological activity suggesting the possibility of using this system of O. decumbens as a renewable source for the production of camptotheca alkaloids. 9-Methoxy camptothecin (9-mCPT), isolated from N. foetida, was a very effective cytotoxic agent as compared to Cr-Nf or CPT-Nf. The IC50 of 9-mCPT was 0.84, 0.32, and 0.35 μg/ml for A549, MCF7 and Jurkat cell lines and >3 μg/ml for U937. Viability assays using MTT dye were further confirmed by assessing extent of apoptosis in these cells. These findings suggest that shoot cultures of O. decumbens offer a rich alternative plant source for the anticancer compound, CPT and 9-mCPT is a more potent compound in N. foetida as compared to CPT.

Esters and amides of maslinic acid trigger apoptosis in human tumor cells and alter their mode of action with respect to the substitution pattern at C-28

Cancer is one of the most commonly diagnosed diseases worldwide; its mortality rate is high, and there is still a demand for the development of antitumor active drugs. Triterpenoic acids show many pharmacological effects, among them antitumor activity. One of these, maslinic acid-1 is of interest because of its antitumor profile. It is not only cytotoxic but also triggers apoptosis in various human tumor cell lines. To improve the cytotoxicity of parent 1 we set out to synthesize a series of esters and amides differing in structure and lipophilicity. These compounds were tested in a sulforhodamine B assay for cytotoxicity, and screened for their ability to induce apoptosis using an acridine orange/propidium iodide assay, DNA laddering and cell cycle experiments. Esters containing small-chain, lipophilic residues increased the cytotoxicity whereas amides as well long-chain esters led to a decrease in activity. The antitumor activity seems to be independent from the substitution pattern at position C-28 for esters and amides but alters their mode of action.

Dual inhibition of MAGL and type II topoisomerase by N-phenylmaleimides as a potential strategy to reduce neuroblastoma cell growth

The endocannabinoid system is implicated in numerous physiopathological processes while more and more pieces of evidence wave the link between this complex machinery and cancer related phenomenon. In these lines, we confirmed the effects of 2-arachidonoylglycerol (2-AG), the main endocannabinoid, on neuroblastoma cells proliferation in vitro, and proved that some N-phenylmaleimide compounds that were previously shown as MAGL inhibitors can also inhibit type 2 topoisomerase. We also shed light on their antiproliferative effects on a neuroblastoma cell line. In order to establish a link between MAGL inhibition, topoisomerase inhibition and the effects on N1E-115 cells, we tested combinations of maleimides or known endocannabinoid metabolism inhibitors and 2-AG, the major MAGL substrate, on N1E-115 cells. However, none of the inhibitors tested, except the carbamate CAY10499, managed to increase 2-AG's effects. Even the MAGL reference inhibitor JZL184 failed to induce a stronger inhibition of proliferation.