Gelselegine-gelsedine type bisindoles as well as the units from Gelsemium elegans with promoting proliferation of oral mucosa fibroblast cells.

Two undescribed bisindole alkaloids, gelseginedine A (1) and its rearranged gelseginedine B (2), and seven unreported gelselegine-type oxindole alkaloids (3-9) were isolated from the stems and leaves of Gelsemium elegans, together with five known alkaloids (10-14). Compounds 1 and 2 represented the first examples of gelselegine-gelsedine type alkaloids which bridged two units by a double bond. Their structures with absolute configurations were elucidated by means of HRESIMS, NMR and calculational chemistry. The performed bioassay revealed that 14 could promote the proliferation of human oral mucosa fibroblast cells.

New Monoterpenoid Indole Hybrids from Gelsemium elegans with Anti-Inflammatory and Osteoclast Inhibitory Activities.

Gelsegansymines A (1) and B (2), two new indole alkaloids along with six known analogues (3-8) were isolated from the aerial parts of Gelsemium elegans. Their structures were elucidated by means of spectroscopic techniques. Structurally, compounds 1 and 2 possessed the rare cage-like gelsedine skeleton hybrid with bicyclic monoterpenoid. The anti-inflammatory activities of isolated compounds (1-3) were tested on LPS induced RAW264.7 cells. Under the treated concentration without toxicity for cells, the cytokines levels of nitric oxide (NO), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were evaluated by Griess method and enzyme-linked immunosorbent assay (ELISA). The results showed that compounds 1-3 exhibited anti-inflammatory activities with dose-dependent manner range from 12.5 to 50 µmol/L. Furthermore, the inhibitory activities of compounds 1 and 2 on receptor activator of NF-κB ligand (RANKL) induced osteoclast formation were tested in vitro. Compounds 1 and 2 at 5 µmol/L exhibited the significant inhibitory effect on the osteoclastogenesis induced by RANKL. This work reported the anti-inflammatory and osteoclast inhibitory activities of new monoterpenoid indole hybrids, which may inspire the further light on the related traditional application research of G. elegans.

Structural Elucidation and Cytotoxic Activity of New Monoterpenoid Indoles from Gelsemium elegans.

Two new monoterpenoid indole alkaloids, gelselegandines F (1) and G (2), were isolated from the aerial parts of Gelsemium elegans. Their structures were elucidated by means of spectroscopic techniques and quantum chemical calculations. The ECD calculations were conducted at the B3LYP/6-311G(d,p) level and NMR calculations were carried out using the Gauge-Including Atomic Orbitals (GIAO) method. Structurally, the two new compounds possessed rare, cage-like, monoterpenoid indole skeletons. All isolated compounds and the total alkaloids extract were tested for cytotoxicity against four different tumor cell lines. The total alkaloids extract of G. elegans exhibited significant antitumor activity with IC50 values ranging from 32.63 to 82.24 ug/mL. In order to discover anticancer leads from the active extraction, both new indole compounds (1-2) were then screened for cytotoxicity. Interestingly, compound 2 showed moderate cytotoxicity against K562 leukemia cells with an IC50 value of 57.02 uM.

Recent progress in chemistry and bioactivity of monoterpenoid indole alkaloids from the genus gelsemium: a comprehensive review.

Monoterpenoid indole alkaloids (MIAs) represent a major class of active ingredients from the plants of the genus Gelsemium. Gelsemium MIAs with diverse chemical structures can be divided into six categories: gelsedine-, gelsemine-, humantenine-, koumine-, sarpagine- and yohimbane-type. Additionally, gelsemium MIAs exert a wide range of bioactivities, including anti-tumour, immunosuppression, anti-anxiety, analgesia, and so on. Owing to their fascinating structures and potent pharmaceutical properties, these gelsemium MIAs arouse significant organic chemists' interest to design state-of-the-art synthetic strategies for their total synthesis. In this review, we comprehensively summarised recently reported novel gelsemium MIAs, potential pharmacological activities of some active molecules, and total synthetic strategies covering the period from 2013 to 2022. It is expected that this study may open the window to timely illuminate and guide further study and development of gelsemium MIAs and their derivatives in clinical practice.

Gelsemium elegans Benth: Chemical Components, Pharmacological Effects, and Toxicity Mechanisms.

Gelsemium elegans Benth (GEB), also known as heartbreak grass, is a highly poisonous plant belonging to the family Loganiaceae and genus Gelsemium that has broad application prospects in medicine. This article reviews its chemical components, pharmacological effects, toxicity mechanisms, and research progress in clinical applications in recent years. Indole alkaloids are the main active components of GEB and have a variety of pharmacological and biological functions. They have anti-tumor, anti-inflammatory, analgesic, and immunomodulation properties, with the therapeutic dose being close to the toxic dose. Application of small-dose indole alkaloids fails to work effectively, while high-dose usage is prone to poisoning, aggravating the patient's conditions. Special caution is needed, especially to observe the changes in the disease condition of the patients in clinical practice. In-depth research on the chemical components and mechanisms of GEB is essential to the development of promising lead compounds and lays the foundation for extensive clinical application and safe usage of GEB in the future.

A network pharmacology-based investigation on the bioactive ingredients and molecular mechanisms of Gelsemium elegans Benth against colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) remains one of the leading causes of cancer-related death worldwide. Gelsemium elegans Benth (GEB) is a traditional Chinese medicine commonly used for treatment for gastrointestinal cancer, including CRC. However, the underlying active ingredients and mechanism remain unknown. This study aims to explore the active components and the functional mechanisms of GEB in treating CRC by network pharmacology-based approaches. METHODS: Candidate compounds of GEB were collected from the Traditional Chinese Medicine@Taiwan, Traditional Chinese Medicines Integrated Database, Bioinformatics Analysis Tool for Molecular mechanism of Traditional Chinese Medicine, and published literature. Potentially active targets of compounds in GEB were retrieved from SwissTargetPrediction databases. Keywords "colorectal cancer", "rectal cancer" and "colon cancer" were used as keywords to search for related targets of CRC from the GeneCards database, then the overlapped targets of compounds and CRC were further intersected with CRC related genes from the TCGA database. The Cytoscape was applied to construct a graph of visualized compound-target and pathway networks. Protein-protein interaction networks were constructed by using STRING database. The DAVID tool was applied to carry out Gene Ontology and Kyoto Encyclopedia of Genes and Genome pathway enrichment analysis of final targets. Molecular docking was employed to validate the interaction between compounds and targets. AutoDockTools was used to construct docking grid box for each target. Docking and molecular dynamics simulation were performed by Autodock Vina and Gromacs software, respectively. RESULTS: Fifty-three bioactive compounds were successfully identified, corresponding to 136 targets that were screened out for the treatment of CRC. Functional enrichment analysis suggested that GEB exerted its pharmacological effects against CRC via modulating multiple pathways, such as pathways in cancer, cell cycle, and colorectal cancer. Molecular docking analysis showed that the representative compounds had good affinity with the key targets. Molecular dynamics simulation indicated that the best hit molecules formed a stable protein-ligand complex. CONCLUSION: This network pharmacology study revealed the multiple ingredients, targets, and pathways synergistically involved in the anti-CRC effect of GEB, which will enhance our understanding of the potential molecular mechanism of GEB in treatment for CRC and lay a foundation for further experimental research.

Monoterpenoid indole alkaloids from the fruits of Gelsemium elegans and their anti-inflammatory activities.

Two novel monoterpenoid indole alkaloids (MIAs), gelsechizines A-B (1-2), along with four known ones (3-6) were isolated from the fruits of Gelsemium elegans. Compound 1 features a new carbon skeleton with two additional carbon atoms forming a 4-methylpyridine unit. Their structures with absolute configurations were elucidated by NMR, MS, X-ray diffraction and electronic circular dichroism (ECD) calculations. Compounds 1-3 showed significant anti-inflammatory effects in vivo and in vitro, which may be related to the inhibition of the trecruitment of neutrophils and macrophages as well as the secretion of TNF-α and IL-6. Preliminary structure-activity relationship analysis revealed that the ß-N-acrylate moiety plays an important role in the anti-inflammatory effect.

Effects of dietary Gelsemium elegans alkaloids on intestinal morphology, antioxidant status, immune responses and microbiota of Megalobrama amblycephala.

Numerous plant extracts used as feed additives in aquaculture have been shown to stimulate appetite, promote growth and enhance immunostimulatory and disease resistance in cultured fish. However, there are few studies on the famous Chinese herbal medicine Gelsemium elegans, which attracts our attention. In this study, we used the Megalobrama amblycephala to investigate the effects of G. elegans alkaloids on fish intestinal health after diet supplementation with 0, 5, 10, 20 and 40 mg/kg G. elegans alkaloids for 12 weeks. We found that dietary G. elegans alkaloids at 40 mg/kg improved intestinal morphology by increasing villus length, muscle thickness and villus number in the foregut and midgut and muscle thickness in the hindgut (P < 0.05). These alkaloids also significantly improved intestinal antioxidant capabilities by increasing superoxide dismutase, catalase, total antioxidant capacity and malondialdehyde levels and up-regulated intestinal Cu/Zn-SOD and Mn-SOD (P < 0.05) at 20 and 40 mg/kg. Dietary G. elegans alkaloids improved intestinal immunity via up-regulating the pro-inflammatory cytokines IL-1ß, IL-8, TNF-α and IFN-α and down-regulating expression of the anti-inflammatory cytokines IL-10 and TGF-ß (P < 0.05) at 20 and 40 mg/kg. The expression of Toll-like receptors TRL1, 3, 4 and 7 were also up-regulated in intestine of M. amblycephala (P < 0.05). In intestinal microbiota, the abundance of Proteobacteria was increased while the Firmicutes abundance was decreased at phylum level after feeding the alkaloids (P < 0.05). The alkaloids also increased the abundance of the probiotic Rhodobacter and decreased the abundance of the pathogenic Staphylococcus at genus level (P < 0.05). In conclusion, dietary G. elegans alkaloid supplementation promoted intestine health by improving intestine morphology, immunity, antioxidant abilities and intestinal microbiota in M. amblycephala.

The Difference in Cytotoxic Activity between Two Optical Isomers of Gelsemine from Gelsemium elegans Benth. on PC12 Cells.

Two optical isomers, +/- gelsemine (1, 2), together with one known compound were isolated from the whole plant of G. elegans. The structures of the separated constituents were elucidated on 1D and 2D (1H-1H COSY, HMBC, HSQC) NMR spectroscopy and high-resolution mass spectrometry (HRMS). The isolated alkaloids were tested in vitro for cytotoxic potential against PC12 cells by the MTT assay. As a result, (+) gelsemine (compound 1) exhibited cytotoxic activity against PC12 cells with an IC50 value of 31.59 µM, while (-) gelsemine (compound 2) was not cytotoxic.

Protective Effect of Koumine, an Alkaloid from Gelsemium Sempervirens, on Injury Induced by H2O2 in IPEC-J2 Cells.

Medicinal herbal plants have been commonly used for intervention in different diseases and improvement of health worldwide. Koumine, an alkaloid monomer found abundantly in Gelsemium plants, can be effectively used as an antioxidant. The purpose of this study was to evaluate the potential protective effect of koumine against hydrogen peroxide (H2O2)-induced oxidative stress and apoptosis in porcine intestinal epithelial cell line (IPEC-J2 cells). MTT assays showed that koumine significantly increased cell viability in H2O2-mediated IPEC-J2 cells. Preincubation with koumine ameliorated H2O2-medicated apoptosis by decreasing reactive oxygen species (ROS) production, and efficiently suppressed the lactate dehydrogenase (LDH) release and malondialdehyde (MDA) production. Moreover, a loss of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) activities was restored to normal level in H2O2-induced IPEC-J2 cells upon koumine exposure. Furthermore, pretreatment with koumine suppressed H2O2-mediated loss of mitochondrial membrane potential, caspase-9 and caspase-3 activation, decrease of Bcl-2 expression and elevation of Bax expressions. Collectively, the results of this study indicated that koumine possesses the cytoprotective effects in IPEC-J2 cells during exposure to H2O2 by suppressing production of ROS, inhibiting the caspase-3 activity and influencing the expression of Bax and Bcl-2. Koumine could potentially serve as a protective effect against H2O2-induced apoptosis.

Beneficial effects of Gelsemium-based treatment against paclitaxel-induced painful symptoms.

Chemotherapeutic drugs induce various side effects including painful peripheral neuropathy that represents a major concern. The widely used anticancer drug paclitaxel causes neurological side effects such as burning pain, allodynia, and hyperalgesia. Neuroprotective substances that may effectively counteract paclitaxel-induced neuropathic symptoms are needed. Here, we investigated the potential of Gelsemium sempervirens (GS) to counteract paclitaxel-evoked painful neuropathy in rats. Using the von Frey hair and acetone behavioral tests, we investigated the potential of GS centesimal (C) dilutions 3, 5, and 9C to prevent or to correct paclitaxel-induced cold allodynia and mechanical allodynia/hyperalgesia involved in neuropathic pain. We found that a prophylactic or corrective treatment with GS dilutions prevented or suppressed PAC-evoked cold allodynia and mechanical allodynia/hyperalgesia, by reversing to normal, decreased cold thermal and mechanical pain thresholds of PAC-treated rats. In particular, preventive or corrective treatments with GS dilution 3C counteracted PAC-evoked allodynic and hyperalgesic responses. Also, GS dilution 5C (in a lesser extent than 3C) significantly reduced PAC-induced mechanical allodynia/hyperalgesia while GS dilution 9C was ineffective. PAC-evoked neuropathic symptoms were efficiently reduced after 1 week treatment with GS dilutions 3 or 5C and the beneficial action increased after 2 weeks. GS dilutions, particularly 3C, also counteracted or prevented PAC-induced sciatic nerve axon alterations and decreased the density of intraepidermal nerve fibers. Altogether, these results obtained in the rat preclinical model suggest that GS dilution-based treatment may constitute an interesting option to explore for the long-term management of pain without undesirable effects.

Ultra-Liquid Chromatography Tandem Mass Spectrometry (UPLC-MS/MS)-Based Pharmacokinetics and Tissue Distribution Study of Koumine and the Detoxification Mechanism of Glycyrrhiza uralensis Fisch on Gelsemium elegans Benth.

Gelsemium elegans Benth. (G. elegans), which is a famous Chinese folk medicine, has been commonly used to treat certain types of skin ulcers and alleviate inflammation, headaches, and cancer pain. However, the extensive clinical use of G. elegans has been greatly hampered by its toxicity. As one of the most widely used herbal medicines, Glycyrrhiza uralensis Fisch, has a unique effect on detoxification of G. elegans. In the present study, a rapid and sensitive method using ultra-liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was established and validated for determination of koumine, the most abundant molecule among the alkaloids of G. elegans, in rat plasma, tissue, and liver microsome. The developed method was successfully applied to the pharmacokinetics, tissue distribution, and in vitro metabolism study in rat with or without pre-treated Glycyrrhiza uralensis Fisch extract. Meanwhile, the expression level of CYP3A1 mRNA was analyzed to explain the detoxification mechanism of Glycyrrhiza uralensis Fisch on G. elegans. As a result, our work demonstrated that Glycyrrhiza uralensis Fisch could significantly affect the pharmacokinetics and tissue distribution of koumine in rats. The detoxification mechanism of Glycyrrhiza uralensis Fisch on G. elegans may be its cytochrome enzyme up-regulation effect.

Gelsecorydines A-E, Five Gelsedine-Corynanthe-Type Bisindole Alkaloids from the Fruits of Gelsemium elegans.

Five monoterpenoid bisindole alkaloids with new carbon skeletons, gelsecorydines A-E (1-5), together with their biogenetic precursors were isolated from the fruits of Gelsemium elegans. Compounds 1-5 represent the first examples of heterodimeric frameworks composed of a gelsedine-type alkaloid and a modified corynanthe-type one. Notably, compound 2 featured an unprecedented caged skeleton with a 6/5/7/6/5/6 heterohexacyclic ring system, which possessed a pyridine ring that linked the two monomers. Their structures and absolute configurations were elucidated by spectroscopic analysis, X-ray diffraction, and electronic circular dichroism (ECD) calculation. A plausible biosynthetic pathway for compounds 1-5 is proposed. Compounds 1, 3, 4, and 5 exhibited a significant inhibitory effect against nitric oxide (NO) production in macrophages.

Cytotoxic gelsedine-type indole alkaloids from Gelsemium elegans.

The ethanol extract of the leaves and branches of Gelsemium elegans afforded three new gelsedine-type indole alkaloids, 11-methoxy-14,15-dihydroxyhumantenmine (1), 11-methoxy-14,15-dihydroxy-19-oxogelsenicine (2), and 11-methoxy-14-hydroxygelsedilam (3), along with one known alkaloid 11-methoxy-14-hydroxyhumantenmine (4). The structures of isolated compounds were established based on 1D and 2D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high-resolution mass spectrometry. The isolated alkaloids were tested in vitro for cytotoxic potential against four laryngeal tumor cell lines including Hep-2, LSC-1, TR-LCC-1, and FD-LSC-1. As a result, compounds 1 and 4 exhibited some cytotoxic activities against all tested tumor cell lines with IC50 values of 10.9-12.1 µM and 9.2-10.8 µM, respectively.

Identification of gelsemine metabolites in rat liver S9 by high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry.

RATIONALE: Gelsemine has been extensively studied because of its anti-tumor, immunomodulatory, insecticidal itching and other significant effects. However, limited information on the pharmacokinetics and metabolism of gelsemine has been reported. Therefore, the purpose of the present study was to investigate the in vitro metabolism of gelsemine in rat liver S9 by using rapid and accurate high-performance liquid chromatography/ quadrupole-time-of-flight mass spectrometry (HPLC/QqTOF-MS). METHODS: The incubation mixture was processed with 15% trichloroacetic acid. Multiple scans of gelsemine metabolites and accurate mass measurements were automatically performed simultaneously through data-dependent acquisition in only 30 min. The structural elucidations of these metabolites were performed by comparing their changes in accurate molecular masses and product ions with those of the parent drug. RESULTS: Five metabolites of gelsemine were identified in rat liver S9. Of these, four metabolites of gelsemine were identified for the first time. The present results showed that the metabolic pathways of gelsemine are oxidation, demethylation, and dehydrogenation in rat liver S9. CONCLUSIONS: In this study, metabolites of gelsemine in liver S9 were identified and elucidated firstly using the HPLC/QqTOF-MS method. The proposed metabolic pathways of gelsemine in liver S9 will provide a basis for further studies of the in vivo metabolism of gelsemine in animals and humans.

Analgesic effects and pharmacologic mechanisms of the Gelsemium alkaloid koumine on a rat model of postoperative pain.

Postoperative pain (POP) of various durations is a common complication of surgical procedures. POP is caused by nerve damage and inflammatory responses that are difficult to treat. The neuroinflammation-glia-steroid network is known to be important in POP. It has been reported that the Gelsemium alkaloid koumine possesses analgesic, anti-inflammatory and neurosteroid modulating activities. This study was undertaken to test the analgesic effects of koumine against POP and explore the underlying pharmacologic mechanisms. Our results showed that microglia and astroglia were activated in the spinal dorsal horn post-incision, along with an increase of proinflammatory cytokines (interleukin 1ß, interleukin 6, and tumor necrosis factor α). Both subcutaneous and intrathecal (i.t.) koumine treatment after incision significantly prevented mechanical allodynia and thermal hyperalgesia, inhibited microglial and astroglial activation, and suppressed expression of proinflammatory cytokines. Moreover, the analgesic effects of koumine were antagonized by i.t. administration of translocator protein (18 kDa) (TSPO) antagonist PK11195 and GABAA receptor antagonist bicuculline. Together, koumine prevented mechanical allodynia and thermal hyperalgesia caused by POP. The pharmacologic mechanism of koumine-mediated analgesia might involve inhibition of spinal neuroinflammation and activation of TSPO. These data suggested that koumine might be a potential pharmacotherapy for the management of POP.

Gelsedine-type oxindole alkaloids from Gelsemium elegans and the evaluation of their cytotoxic activity.

Phytochemical investigation on the 70% EtOH extract of the leaves and branches of Gelsemium elegans resulted into the isolation of five new gelsedine-type oxindole alkaloids, gelseleganins A-E (1-5). The structures of the isolated compounds were established based on 1D and 2D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. The isolated alkaloids were tested in vitro for cytotoxic potential against seven tumor cell lines. As a result, alkaloids 3 exhibited significant cytotoxic activities against all the tested tumor cell lines with IC50 values <10µM.

Five new koumine-type alkaloids from the roots of Gelsemium elegans.

Five new koumine-type alkaloids (1-5) along with six known ones were isolated from the roots of Gelsemium elegans. Their structures with absolute configurations were elucidated on the basis of NMR spectroscopy and electronic circular dichroism spectral analyses. The inhibitory effects of compounds 1-11 on the viability of three tumor cell lines (A-649, HepG2, and HuH7) were evaluated by the MTT assay.

Effects of Koumine on Adjuvant- and Collagen-Induced Arthritis in Rats.

To examine the effect of koumine, a Gelsemium alkaloid, on two experimental models of rheumatoid arthritis (RA), rats with adjuvant-induced arthritis (AIA) and collagen-induced arthritis (CIA) were administered koumine (0.6, 3, or 15 mg/kg/day) or vehicle through gastric gavage (i.g.). Clinical evaluation was performed via measurements of hind paw volume, arthritis index (AI) score, mechanical withdrawal threshold, organ weight, and by radiographic and histological examinations. Levels of interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, and antitype II collagen (CII) antibody were also examined. In rats with AIA, koumine reduced the AI score and mechanical allodynia of the injected hind paw in a dose-dependent manner and significantly inhibited increase in thymus and liver weights. In rats with CIA, koumine inhibited increase in hind paw volume, AI score, and mechanical allodynia in a dose-dependent manner and reduced joint space narrowing. Furthermore, koumine also attenuated the increase in the expression of IL-1ß and TNF-α, as well as the robust increase of serum anti-CII antibodies in response to immunization. These results suggested that koumine effectively attenuated arthritis progression in two rat models of RA and that this therapeutic effect may be associated with its immunoregulatory action.

New nor-ursane type triterpenoids from Gelsemium elegans.

Five new nor-ursane type triterpenoids, gelse-norursane A-E, together with twenty known compounds, were isolated from the whole plant of Gelsemium elegans. The structures of new compounds were established as (2R,3R,7R,17S,19R)-2,3,7,19-tetrahydroxy-6-oxo-24-norurs-4(23),12-dien-28-oic acid (1), (2R,3R,7R,17S)-2,3,7-trihydroxy-6-oxo-24-norurs-4(23), 12-dien-28-oic acid (2), (2R,3R,7R,17S)-2,3,4-trihydroxy-23-norurs-20(30),12-dien-28-oic acid (3), (2R,3R,30R)-2,3-dihydroxy-24-norurs-4(23),12-dien-30-oic acid (4), and (2R,3R,30R)-2, 3-dihydroxy-24-norurs-4,12-dien-30-oic acid (5), using spectroscopic analysis, including HRESIMS, 1D and 2D NMR. The absolute configurations of 1 and 4 were established through comparison of experimental and calculated ECD spectra. The gelse-norursane A-E are isolated as the 24-nor-ursane type triterpenoids from the family Loganiaceae for the first time. The cytotoxicities of the selected compounds against a panel of four human cancer HL60, Hela, Hep-G2, and Smmc 7221 cell lines were evaluated using the MTT assay in vitro.