Role of limonin in anticancer effects of Evodia rutaecarpa on ovarian cancer cells

Natural anticancer agents: prospection of medicinal and aromatic plants in modern chemoprevention and chemotherapy

Natural products obtained from medicinal and aromatic plants are increasingly recognized as promising anticancer agents due to their structural richness, including terpene and flavonoid molecules, which induce apoptosis and modulate gene expression. These compounds offer an alternative to conventional treatments, often costly, which face challenges such as multidrug resistance. This review aims to provide a promising alternative approach to effectively control cancer by consolidating significant findings in identifying natural products and anticancer agent development from medicinal and aromatic plants. It synthesizes the findings of a comprehensive search of academic databases, such as PubMed and Springer, prioritizing articles published in recognized peer-reviewed journals that address the bioprospecting of medicinal and aromatic plants as anticancer agents. The review addresses the anticancer activities of plant extracts and essential oils, which were selected for their relevance to chemoprevention and chemotherapy. Compounds successfully used in cancer therapy include Docetaxel (an antimitotic agent), Etoposide VP-16 (an antimitotic agent and topoisomerase II inhibitor), Topotecan (a topoisomerase I inhibitor), Thymoquinone (a Reactive Oxygen Species-ROS inducer), and Phenethyl isothiocyanate (with multiple mechanisms). The review highlights natural products such as Hinokitiol, Mahanine, Hesperetin, Borneol, Carvacrol, Eugenol, Epigallocatechin gallate, and Capsaicin for their demonstrated efficacy against multiple cancer types, including breast, cervical, gastric, colorectal, pancreatic, lung, prostate, and skin cancer. Finally, it highlights the need for continued bioprospecting studies to identify novel natural products that can be successfully used in modern chemoprevention and chemotherapy.

Selection of Reference Genes in Evodia rutaecarpa var. officinalis and Expression Patterns of Genes Involved in Its Limonin Biosynthesis

E. rutaecarpa var. officinalis is a traditional Chinese medicinal plant known for its therapeutic effects, which encompass the promotion of digestion, the dispelling of cold, the alleviation of pain, and the exhibition of anti-inflammatory and antibacterial properties. The principal active component of this plant, limonin, is a potent triterpene compound with notable pharmacological activities. Despite its significance, the complete biosynthesis pathway of limonin in E. rutaecarpa var. officinalis remains incompletely understood, and the underlying molecular mechanisms remain unexplored. The main purpose of this study was to screen the reference genes suitable for expression analysis in E. rutaecarpa var. officinalis, calculate the expression patterns of the genes in the limonin biosynthesis pathway, and identify the relevant enzyme genes related to limonin biosynthesis. The reference genes play a pivotal role in establishing reliable reference standards for normalizing the gene expression data, thereby ensuring precision and credibility in the biological research outcomes. In order to identify the optimal reference genes and gene expression patterns across the diverse tissues (e.g., roots, stems, leaves, and flower buds) and developmental stages (i.e., 17 July, 24 August, 1 September, and 24 October) of E. rutaecarpa var. officinalis, LC-MS was used to analyze the limonin contents in distinct tissue samples and developmental stages, and qRT-PCR technology was employed to investigate the expression patterns of the ten reference genes and eighteen genes involved in limonin biosynthesis. Utilizing a comprehensive analysis that integrated three software tools (GeNorm ver. 3.5, NormFinder ver. 0.953 and BestKeeper ver. 1.0) and Delta Ct method alongside the RefFinder website, the best reference genes were selected. Through the research, we determined that Act1 and UBQ served as the preferred reference genes for normalizing gene expression during various fruit developmental stages, while Act1 and His3 were optimal for different tissues. Using Act1 and UBQ as the reference genes, and based on the different fruit developmental stages, qRT-PCR analysis was performed on the pathway genes selected from the "full-length transcriptome + expression profile + metabolome" data in the limonin biosynthesis pathway of E. rutaecarpa var. officinalis. The findings indicated that there were consistent expression patterns of HMGCR, SQE, and CYP450 with fluctuations in the limonin contents, suggesting their potential involvement in the limonin biosynthesis of E. rutaecarpa var. officinalis. This study lays the foundation for further research on the metabolic pathway of limonin in E. rutaecarpa var. officinalis and provides reliable reference genes for other researchers to use for conducting expression analyses.

Metabolomic Analysis of Phytochemical Compounds from Ethanolic Extract of Lime (Citrus aurantifolia) Peel and Its Anti-Cancer Effects against Human Hepatocellular Carcinoma Cells

Lime peels are food waste from lime product manufacturing. We previously developed and optimized a green extraction method for hesperidin-limonin-rich lime peel extract. This study aimed to identify the metabolomics profile of phytochemicals and the anti-cancer effects of ethanolic extract of lime (Citrus aurantifolia) peel against liver cancer cells PLC/PRF/5. The extract’s metabolomics profile was analyzed by using LC-qTOF/MS and GC-HRMS. The anti-cancer effects were studied by using MTT assay, Annexin-PI assay, and Transwell-invasion assay. Results show that the average IC50(s) of hesperidin, limonin, and the extract on cancer cells’ viability were 165.615, 188.073, and 503.004 µg/mL, respectively. At the IC50 levels, the extract induced more apoptosis than those of pure compounds when incubating for 24 and 48 h (p < 0.0001). A combination of limonin and hesperidin showed a synergistic effect on apoptosis induction (p < 0.001), but the effect of the combination was still less than that of the extract at 48 h. Furthermore, the extract significantly inhibited cancer cell invasion better than limonin but equal to hesperidin. At the IC50 level, the extract contains many folds lower amounts of hesperidin and limonin than the IC50 doses of the pure compounds. Besides limonin and hesperidin, there were another 60 and 22 compounds detected from the LCMS and GCMS analyses, respectively. Taken altogether, the superior effect of the ethanolic extract against liver cancer cells compared to pure compound likely results from the combinatorial effects of limonin, hesperidin, and other phytochemical components in the extract.

Traditional Chinese medicine Euodiae Fructus: botany, traditional use, phytochemistry, pharmacology, toxicity and quality control

Euodiae Fructus, referred to as "Wuzhuyu" in Chinese, has been used as local and traditional herbal medicines in many regions, especially in China, Japan and Korea, for the treatment of gastrointestinal disorders, headache, emesis, aphtha, dermatophytosis, dysentery, etc. Substantial investigations into their chemical and pharmacological properties have been performed. Recently, interest in this plant has been focused on the different structural types of alkaloids like evodiamine, rutaecarpine, dehydroevodiamine and 1-methyl-2-undecyl-4(1H)-quinolone, which exhibit a wide range of pharmacological activities in preclinical models, such as anticancer, antibacterial, anti-inflammatory, anti-cardiovascular disease, etc. This review summarizes the up-to-date and comprehensive information concerning the botany, traditional uses, phytochemistry, pharmacology of Euodiae Fructus together with the toxicology and quality control, and discusses the possible direction and scope for future research on this plant.

Analysis of the Molecular Mechanism of Evodia rutaecarpa Fruit in the Treatment of Nasopharyngeal Carcinoma Using Network Pharmacology and Molecular Docking

Background

Nasopharyngeal carcinoma (NPC), a neoplasm of the head and neck, has high incidence and mortality rates in East and Southeast Asia. Evodia rutaecarpa is a tree native to Korea and China, and its fruit (hereafter referred to as Evodia) exhibits remarkable antitumour properties. However, little is known about its mechanism of action in NPC. In this study, we employed network pharmacology to identify targets of active Evodia compounds in nasopharyngeal carcinoma and generate an interaction network.

Methods

The active ingredients of Evodia and targets in NPC were obtained from multiple databases, and an interaction network was constructed via the Cytoscape and STRING databases. The key biological processes and signalling pathways were predicted using Gene Ontology and Kyoto Encyclopaedia of Genes and Genomes pathway enrichment analyses. Molecular docking technology was used to identify the affinity and activity of target genes, and The Cancer Genome Atlas and Human Protein Atlas databases were used to analyse differential expression. Cell Counting Kit-8 (CCK-8) and Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) dual-fluorescence staining were used for experimental verification.

Results

Active Evodia compounds included quercetin, isorhamnetin, and evodiamine, and important NPC targets included MAPK14, AKT1, RELA, MAPK1, JUN, and p53, which were enriched in lipid and atherosclerosis signalling pathways. Additionally, we verified the high affinity and activity of the active compounds through molecular docking, and the target proteins were verified using immunohistochemistry and differential expression analyses. Furthermore, CCK-8 assays and Annexin V-FITC/PI dual-fluorescence staining showed that isorhamnetin inhibited the proliferation of NPC cells and induced apoptosis.

Conclusion

Our results identified the molecular mechanisms of Evodia and demonstrated its ability to alter the proliferation and apoptosis of NPC cells through multiple targets and pathways, thereby providing evidence for the clinical application of Evodia.

Dehydroevodiamine inhibits lung metastasis by suppressing survival and metastatic abilities of colorectal cancer cells

BACKGROUND

Despite the rising 5-year survival rate of colorectal cancer (CRC) patients, the survival rate decreases as the stage progress, and a low survival rate is highly associated with metastasis.

PURPOSE

The purpose of our study is to investigate the effect of dehydroevodiamine (DHE) on the lung metastasis of CRC and the proliferation of CRC cells.

STUDY DESIGN

Cell death was confirmed after DHE treatment on several CRC cell lines. The mechanism of cell cytotoxicity was found using flow cytometry. After that, the expression of the proteins or mRNAs related to the cell cytotoxicity was confirmed. Also, anti-metastatic ability of DHE in CRC cells was measured by checking the expression of Epithelial to Mesenchymal Transition (EMT) markers. Lung metastasis mouse model was established, and DHE was administered orally for 14 days.

RESULTS

DHE suppressed the viability of HCT116, CT26, SW480, and LoVo cells. DHE treatment led to G2/M arrest via a reduction of cyclin B1/CDK1 and caspase-dependent apoptosis. It also induced autophagy by regulating LC3-II and beclin-1 expression. Additionally, migration and invasion of CRC cells were decreased by DHE through regulation of the expression of EMT markers. Oral administration of DHE could inhibit the lung metastasis of CT26 cells in an in vivo model.

CONCLUSION

Our study demonstrated that DHE has a potential therapeutic effect on colorectal cancer metastasis.

A Green Extraction Method to Achieve the Highest Yield of Limonin and Hesperidin from Lime Peel Powder (Citrus aurantifolia)

Green extraction is aimed at reducing energy consumption by using renewable plant sources and environmentally friendly bio-solvents. Lime (Citrus aurantifolia) is a rich source of flavonoids (e.g., hesperidin) and limonoids (e.g., limonin). Manufacturing of lime products (e.g., lime juice) yields a considerable amount of lime peel as food waste that should be comprehensively exploited. The aim of this study was to develop a green and simple extraction method to acquire the highest yield of both limonin and hesperidin from the lime peel. The study method included ethanolic-aqueous extraction and variable factors, i.e., ethanol concentrations, pH values of solvent, and extraction temperature. The response surface methodology was used to optimize extraction conditions. The concentrations of limonin and hesperidin were determined by using UHPLC-MS/MS. Results showed that the yields of limonin and hesperidin significantly depended on ethanol concentrations and extraction temperature, while pH value had the least effect. The optimal extraction condition with the highest amounts of limonin and hesperidin was 80% ethanol at pH 7, 50 °C, which yields 2.072 and 3.353 mg/g of limonin and hesperidin, respectively. This study illustrates a green extraction process using food waste, e.g., lime peel, as an energy-saving source and ethanol as a bio-solvent to achieve the highest amount of double bioactive compounds.

Evodiamine induces ROS-Dependent cytotoxicity in human gastric cancer cells via TRPV1/Ca2+ pathway

Evodiamine (EVO), a key active ingredient of the fruit of Evodiae fructus, is provided with antitumor effects (mainly cytotoxic effect) including proliferation inhibition, cell cycle arrest, apoptosis, and metastasis inhibition. Our study aims to explain the underlying role of TRPV1/Ca2+ in EVO-induced cytotoxicity in human gastric cancer cells. Human gastric cancer line BGC-823 was used to study EVO-induced cytotoxicity. Cell viability was examined using CCK-8 assay. Apoptosis was examined using Annexin V-FITC/PI staining assay. Intracellular ROS ([ROS]i) levels were examined using DCFH-DA assay. Mitochondrial morphology was examined using Mitotracker Green staining. Mitochondrial membrane potential (Δψm) were examined using JC-1 assay. Intracellular Ca2+ levels ([Ca2+]i) were examined using Fluo-4 AM assay. Mitochondrial ROS ([ROS]m)levels were examined using Mitotracker Green/MitoSOX Red staining. Mitochondrial Ca2+ ([Ca2+]m)levels were examined using Mitotracker Green/Rhod-2 Red staining. The protein levels was detected by Western blot. EVO exposure causes significant ROS generation and apoptotic cell death. Pretreatment of EUK134 significantly ameliorated EVO-induced apoptotic cell death. Furthermore, EVO exposure induced [ROS]i generation and mitochondrial dysfunction, including [ROS]m generation and Δψm dissipation, which can be significantly attenuated by pre-incubation of rotenone indicating that [ROS]m is the main source of EVO-induced intracellular ROS generation. Importantly, EVO-induced cytotoxicity was significantly ameliorated by intracellular Ca2+ chelation, confirming that EVO induces cell death through Ca2+ overload. Pharmacological and genetic inhibition of TRPV1 could significantly attenuate Ca2+ influx, ROS generation and apoptotic cell death induced by EVO exposure, while exogenous TRPV1 overexpression could augment the EVO-induced cytotoxicity. Moreover, genetic inhibition of mitochondrial calcium uniporter (MCU) attenuated EVO-induced cell death and mitochondrial dysfunction. EVO exposure induced endoplasmic reticulum (ER) stress demonstrated by the activation of PERK/CHOP in cells exposed to EVO, and PERK/CHOP activation was depleted by EUK134 pre-treatment. Our results support the concept that EVO induces ROS-dependent cytotoxicity via TRPV1/Ca2+ Pathway.

Research progress on evodiamine, a bioactive alkaloid of Evodiae fructus: Focus on its anti-cancer activity and bioavailability (Review)

Evodiae fructus (Wu-Zhu-Yu in Chinese) can be isolated from the dried, unripe fruits of Tetradium ruticarpum and is a well-known traditional Chinese medicine that is applied extensively in China, Japan and Korea. Evodiae fructus has been traditionally used to treat headaches, abdominal pain and menorrhalgia. In addition, it is widely used as a dietary supplement to provide carboxylic acids, essential oils and flavonoids. Evodiamine (EVO) is one of the major bioactive components contained within Evodiae fructus and is considered to be a potential candidate anti-cancer agent. EVO has been reported to exert anti-cancer effects by inhibiting cell proliferation, invasion and metastasis, whilst inducing apoptosis in numerous types of cancer cells. However, EVO is susceptible to metabolism and may inhibit the activities of metabolizing enzymes, such as cytochrome P450. Clinical application of EVO in the treatment of cancers may prove difficult due to poor bioavailability and potential toxicity due to metabolism. Currently, novel drug carriers involving the use of solid dispersion techniques, phospholipids and nanocomplexes to deliver EVO to improve its bioavailability and mitigate side effects have been tested. The present review aims to summarize the reported anti-cancer effects of EVO whilst discussing the pharmacokinetic behaviors, characteristics and effective delivery systems of EVO.

Rutaecarpine administration inhibits cancer cell growth in allogenic TRAMP-C1 prostate cancer mice correlating with immune balance in vivo

BACKGROUND

Rutaecarpine (Rut) is a plant alkaloid abundant in Euodia ruticarpa which is a Chinese herbal medicine used for treating various cancers. However, the Rut administration effect on prostate cancer in vivo remains unclear.

AIM

In the present study we established an allogenic TRAMP-C1 prostate cancer mouse model to evaluate the Rut administration effect and mechanism in vivo.

METHODS

To unravel the Rut administration effect on prostate cancer in vivo, C57BL/6J male mice (8 weeks old) were randomly grouped (n = 9), subcutaneously loaded with TRAMP-C1 prostate cancer cells and immediately given daily by gavage with Rut dissolved in soybean oil at 7 mg (low dose), 35 mg (medium dose), and 70 mg/kg b.w./day (high dose) for successive 39 days.

RESULTS

Rut administration significantly and dose-dependently reduced both tumor volume and solid prostate cancer weight in allogenic TRAMP-C1 male mice. Rut administration markedly increased (TNF-α+IFN-γ) (Th1-)/IL-10 (Th2-) cytokine secretion ratios by splenocytes and TNF-α (M1-)/IL-10 (M2-) cytokine secretion ratios by macrophages as compared to those of dietary control group, suggesting that Rut administration in vivo regulates the immune balance toward Th1- and M1-polarized characteristics. Decreased CD19⁺, CD4⁺ and CD8⁺ lymphocytes in the peripheral blood of allogenic TRAMP-C1 mice were significantly elevated by Rut administration. Tumor weights positively correlated with TNF-α secretions by splenocytes, suggesting that there is a tumor cachexia in the tumor-bearing mice. Tumor weights negatively correlated with IgG (Th1-antibody) levels in the sera, suggesting that Th1-polarized immune balance may inhibit prostate cancer cell growth.

CONCLUSIONS

Our results evidenced that Rut administration suppresses prostate cancer cell growth in mice subcutaneously loaded with TRAMP-C1 cells and correlated the anti-cancer effects with Th1-polarized immune balance in vivo.

Limonin induces apoptosis of HL-60 cells by inhibiting NQO1 activity

Limonin is an important bioactive substance in citrus fruits, especially in seeds, which has great potential in cancer prevention and treatment. In order to explore the anticancer activity based on interaction between limonin and NQO1, Human promyelocytic leukemia cells (HL-60) were studied in vitro. We found that limonin could inhibit proliferation and promote apoptosis of HL-60 cells, and the effect was positively correlated with its dosage. Western blot results showed that limonin could activate the endogenous apoptosis pathway mediated by mitochondria via up-regulating pro-apoptotic proteins (Bax, cytochrome c, Caspase3, and Caspase9) and down-regulating anti-apoptotic proteins (Bcl-2), thus inhibiting the proliferation of HL-60 cells and promoting apoptosis, which further proved the anticancer activity of limonin from the molecular mechanism. At the same time, limonin down-regulated the expression of NQO1, indicating that limonin may indirectly act on the apoptosis pathway by regulating the expression activity of antioxidant enzymes in vivo, thus exerting its inhibitory effect on tumor cells, which provides an idea for the molecular mechanism that natural products can indirectly exert their anticancer effect by regulating the activity of antioxidant enzymes.