New polyoxypregnane glycosides from the roots of Marsdenia tenacissima

A new pregnane glycoside from Marsdenia tenacissima and its cytotoxic and NO inhibitory activities

The Marsdenia tenacissima, has been used as traditional Chinese medicine for six hundred years. Our chemical investigation on the stem of Marsdenia tenacissima led to the isolation of one new pregnane glycoside, namely, marsdeoside J (compound 1) and twelve known compounds. The structure of the new compound was elucidated by spectroscopic analysis including 1D and 2D NMR, HRESIMS, IR, and UV. The absolute configurations of the sugar moiety were identified by comparing the specific optical rotations and Rf values with those of the commercially available standards and the data reported in the literature. Compound 1 showed cytotoxicities against five human cancer cell lines, with IC50 values ranging from 6.5 to 18.1 μM and certain inhibitory activities on NO production.

Marsdenia tenacissima injection induces the apoptosis of prostate cancer by regulating the AKT/GSK3β/STAT3 signaling axis

Marsdenia tenacissima injection, a standard Marsdenia tenacissima extract (MTE), has been approved as an adjuvant therapeutic agent for various cancers. Our previous study showed that MTE inhibited the proliferation and metastasis of prostate cancer (PCa) cells. However, the underlying mechanisms and active ingredients of MTE against PCa were not completely understood. This study revealed that MTE induced significant decreases in cell viability and clonal growth in PCa cells. In addition, MTE induced the apoptosis of DU145 cells by reducing the mitochondrial membrane potential and increasing the expression of Cleaved Caspase 3/7, Cyt c, and Bax. In vivo, DU145 xenografted NOD-SCID mice treated with MTE showed significantly decreased tumor size. TUNEL staining and Western blot confirmed the pro-apoptotic effects of MTE. Network pharmacology analysis collected 196 ingredients of MTE linked to 655 potential targets, and 709 PCa-associated targets were retrieved, from which 149 overlapped targets were screened out. Pathway enrichment analysis showed that the HIF-1, PI3K-AKT, and ErbB signaling pathways were closely related to tumor apoptosis. Western blot results confirmed that MTE increased the expression of p-AKT^Ser473 and p-GSK3β^Ser9, and decreased the expression of p-STAT3^Tyr705in vitro and in vivo. A total of 13 compounds in MTE were identified by HPLC-CAD-QTOF-MS/MS and UPLC-QTOF-MS/MS. Molecular docking analysis indicated that six compounds may interact with AKT, GSK3β, and STAT3. In conclusion, MTE induces the endogenous mitochondrial apoptosis of PCa by regulating the AKT/GSK3β/STAT3 signaling axis, resulting in inhibition of PCa growth in vitro and in vivo.

Polyoxypregnane Glycosides from Root of Marsdenia tenacissima and Inhibited Nitric Oxide Levels in LPS Stimulated RAW 264.7 Cells

Six new polyoxypregnane glycosides, marstenacisside F1−F3 (1−3), G1−G2 (4−5) and H1 (6), as well as 3-O-β-D-glucopyranosyl-(1→4)-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-11α,12β-di-O-benzoyl-tenacigenin B (7), were isolated from the roots of Marsdenia tenacissima. Their structures were established by an extensive interpretation of their 1D and 2D NMR and HRESIMS data. Compounds 1−7 were tenacigenin B derivatives with an oligosaccharide chain at C-3. This was the first time that compound 7 had been isolated from the title plant and its 1H and 13C NMR data were reported. Compounds 4 and 5 were the first examples of C21 steroid glycoside bearing unique β-glucopyranosyl-(1→4)-β-glucopyranose sugar moiety. All the isolated compounds were evaluated for anti-inflammatory activity by inhibiting nitric oxide (NO) production in the lipopolysaccharide-induced RAW 264.7 cells. The results showed that marstenacisside F1 and F2 exhibited significant NO inhibitory activity with an inhibition rate of 48.19 ± 4.14% and 70.33 ± 5.39%, respectively, at 40 μM, approximately equal to the positive control (L-NMMA, 68.03 ± 0.72%).

Steroid glycosides from the roots of Marsdenia tenacissima

Eleven undescribed glycosylated C₂₁ steroids and nine known homologous glycosides with diverse acyl substituents, as well as their common steroid aglycone, have been obtained from the roots of Marsdenia tenacissima. Their structures were elucidated mainly by comprehensive spectroscopic analyses and comparison with previously reported analogues, with the absolute configuration assignment being supported by chemical degradation, X-ray crystallography and ECD exciton chirality method. Among them, two pairs of regioisomers were found to exist as inseparable equilibrium mixtures due to an interesting intramolecular transesterification, and nicotinoyl substitution was first reported for metabolites from the title plant. Screening of these compounds in a panel of bioassays revealed that two glycosides displayed mild inhibition against butyrylcholinesterase.

Discovery of Polyoxypregnane Derivatives From Aspidopterys obcordata With Their Potential Antitumor Activity

The bioassay-guided phytochemical study of an ethnic medicinal plant Aspidopterys obcorda ta Hemsl. var. obcordata results in the isolation of eight new polyoxypregnane derivatives, named aspidatasides A–H (1–8), along with ten known analogs (9–18). The series polyoxypregnane derivatives were screened for their cytoxic activity against HL-60 cells, and compound 2 showed the highest potency with an IC₅₀ 8.03 μM. Preliminary structure–activity relationship studies displayed that the sugar chain and double bond could notably impact their biological activity.

Rapid identification and structural characterization of polyoxypregnane glycosides in Dregea sinensis by HPLC-MSn and HRMS

By HPLC-MSⁿ and HRMS analyses, the structures of 52 polyoxypregnane glycosides were rapidly inferred from Dregea sinensis Hemsl on the basis of their sodium-cationized molecules [M + Na]⁺ and predominant diagnostic ions resulting from the saccharic chain on C3 and the neutral loss of substituent on C11 and C12. Compounds 1 and 7 significantly inhibited LPS-stimulated splenocyte proliferation in vitro.[Formula: see text].

Synthesis and characterization of gold nanoparticles from Marsdenia tenacissima and its anticancer activity of liver cancer HepG2 cells

Nowadays, the synthesis and characterization of gold nanoparticles (AuNPs) from plant based extracts and effects of their anticancer have concerned an important interest. Marsdenia tenacissima (MT), a conventional Chinese herbal medicine, has long been used for thousands of years to treat tracheitis, asthma, rheumatism, etc. In this present study, we optimize the reaction of parameters to manage the nanoparticle size, which was categorized by high-resolution transmission electron microscopy (HR-TEM). A different characterization method, for example, UV-visible spectroscopy (UV-vis), fourier-transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) were performed to consider the synthesized AuNPs getting from the MT leaf extract. The MT-AuNPs were analyzed for their cytotoxicity property against HepG2 cells by MTT analysis. The apoptosis was evaluated by using reactive oxygen species (ROS), migration assay, mitochondrial membrane potential (MMP) and apoptotic protein expression. Interestingly, the findings of our study observed the cytotoxicity effect of synthesized MT-AuNPs at a concentration of 59.62 ± 4.37 μg after 24 hrs treatment. Apoptosis was induced by the MT-AuNPs with enhanced ROS, changed MMP and inhibit the migration assay. Finally, the apoptosis was confirmed by the considerable up-regulation of Bax, caspase-9 and caspase-3, while the anti-apoptotic protein expressions of Bcl-2 and Bcl-XL were down-regulated. Although, in this studies, we evaluated the characterization, synthesis and anticancer action of gold nanoparticles from MT (MT-AuNPS) helpful for liver cancer therapeutics.

Tenacigenin B ester derivatives from Marsdenia tenacissima actively inhibited CYP3A4 and enhanced in vivo antitumor activity of paclitaxel

ETHNOPHARMACOLOGICAL RELEVANCE

Marsdenia tenacissima (Roxb.) Wight et Arn is a vine distributed in southwest area of China and used in folk medicine for treatment of tumors. Recent decades of studies on this plant reveal its synergistic effects with certain anticancer drugs in cancer therapy. In our previous study, an extract ETA which contains total aglycones made from M. tenacissima significantly enhanced antitumor activity of paclitaxel in tumor-bearing mice. However, the effective constituents in ETA and the underlying mechanisms remain unclear.

AIM OF THE STUDY

Reveal the active components in ETA as well as the molecular mechanism in enhancing antitumor efficacy of paclitaxel.

MATERIAL AND METHODS

Main constituents in ETA were purified by chemical methods. Effects of the purified constituents on metabolic activity of CYP450 enzymes were evaluated in human liver microsomes. Ability of the constituents to enhance antitumor activity of paclitaxel were investigated in nude mice bearing HeLa tumors. Pharmacokinetic study was performed in SD rats. Molecular docking was carried out for investigation of drug-protein interactions.

RESULTS

Three main C₂₁ steroidal aglycones, 11α-O-tigloyl-12β-O-acetyl-tenacigenin B (MT1), 11α-O-2-methylbutanoyl-12β-O-tigloyl-tenacigenin B (MT2) and 11α-O-2-methylbutanoyl-12β-O-acetyl-tenacigenin B (MT3), together with tenacigenin B (MT4) was prepared from ETA. Among them, MT1, MT2 and MT3 strongly inhibit the metabolic activity of CYP3A4. MT2 also showed inhibitory effects on CYP2C8, CYP2B6 and CYP2C19. In HeLa tumor xenografts, MT1, MT2 and MT3 (30 mg/kg) did not affect tumor growth themselves, but significantly enhanced paclitaxel-induced growth inhibition. In addition, coadministration of MT2 with paclitaxel resulted in significant reduction of liver CYP2C8. In pharmacokinetic study, MT2 significantly increased the blood concentration of paclitaxel with increased AUC value by 2.2-5.3 folds. Molecular docking analysis suggested hydrophobic interaction modes of tenacigenin B derivatives with CYP3A4, and also the essential roles of the C-11 and C-12 ester groups for effective interaction with CYP3A4.

CONCLUSION

Our study proves that, 11α-O-tigloyl-12β-O-acetyl-tenacigenin B, 11α-O-2-methylbutanoyl-12β-O-tigloyl-tenacigenin B and 11α-O-2-methylbutanoyl-12β-O-acetyl-tenacigenin B, which are the main constituents of ETA, are active inhibitors of CYP3A4 with potential to increase therapeutic efficacy of anticancer drugs that are substrates of CYP3A4. Tenacigenin B derivatives with C-11 and C-12 ester group substitutions, or at least a large part of them, are active components in ETA and M. tenacissima to enhance in vivo antitumor efficacies of paclitaxel.

The Antitumor Activities of Marsdenia tenacissima

Marsdenia tenacissima (MT), a traditional Chinese herbal medicine, has long been used for thousands of years to treat asthma, tracheitis, rheumatism, etc. An increasing number of recent studies have focused on the antitumor effects of MT. The effects of MT on cancer are the result of various activated signaling pathways and inhibiting factors and the high expression levels of regulatory proteins. MT can inhibit different cancer types including non-small cell lung cancer (NSCLC), malignant tumors, hepatic carcinoma, and so on. This article mainly focuses on the activities and mechanisms of MT. In addition, the efficacy and toxicity of MT are also discussed. Further studies of MT are required for improved medicinal utilization.

Marsdenia tenacissima: A Review of Traditional Uses, Phytochemistry and Pharmacology

The stems and roots of Marsdenia tenacissima (Roxb.) Wight et Arn., a traditional Chinese medicine and Dai herbal medicine, have been widely used for the treatment of asthma, trachitis, tonsillitis, pharyngitis, cystitis, pneumonia and drug or food poisoning. Nowadays, the extract of Marsdenia tenacissima, under the trademark of "Xiao-ai-ping", is widely used in clinic for the treatment of different cancers in China. To date, approximately 196 chemical ingredients covering steroids, triterpenes and organic acids have been identified from different parts of this plant. Steroids are the major characteristic and bioactive constituents of this plant. Modern pharmacology has demonstrated that the crude extracts and steroids have various in vitro and in vivo pharmacological activities, such as multidrug resistance reversal, antitumor, anti-angiogenic, immunomodulation and anti-HIV activities. The multidrug resistance reversal of steroids provided evidence for the use of this herb in clinic. However, despite wide clinical application, clinical trials, quality control method, pharmacokinetic and toxicity research on Marsdenia tenacissima were seldom reported and deserved further efforts. The present review aimed to achieve a comprehensive and up-to-date investigation in ethnopharmacology, phytochemistry, pharmacology, clinical study, pharmacokinetics, toxicology and quality control of Marsdenia tenacissima. In addition, the possible perspectives and trends for future studies of Marsdenia tenacissima have also been put forward. It is believed that this review would provide a theoretical basis and valuable data for future in-depth studies and applications.

Rapid structure prediction by HPLC-ESI-MSn of twenty-five polyoxypregnane tetraglycosides from Dregea sinensis with NMR confirmation of eight structures

Dregea sinensis Hemsl is an important herbal medicine in the Dai nationality of China. Its prominent clinical application has generated interest in the polyoxypregnane glycosides of the plant. This paper describes an extension of previous research on the polyoxypregnane di- and triglycosides of D. sinensis, aiming at identifying related tetraglycosides. On the basis of HPLC-ESI-MSⁿ analysis in positive mode, twenty-five previously undescribed polyoxypregnane tetraglycosides were characterized (regarding molecular masses and fragmentation in MSⁿ) from an ethyl acetate fraction that was not previously investigated. Guided by MSⁿ fragmentation and known structures of related di- and triglycosides from D. sinensis, tentative structures were predicted from the MS data. In order to test the predictions, eight of the glycosides were isolated and their structures were elucidated by 1D and 2D NMR methods, confirming the tentative predictions. Finally, the cytotoxicity of the isolates was evaluated on several human cell lines with little effect in general, even though slight inhibitory effects of four polyoxypregnane glycosides were detected at 10 μM against the human leukemia cell line HL-60.

C21 steroid derivatives from the Dai herbal medicine Dai-Bai-Jie, the dried roots of Marsdenia tenacissima, and their screening for anti-HIV activity

Twenty-three new C₂₁ steroidal glycosides, marstenacissides C1-C10 (1-10), D1-D7 (11-17) and E1-E6 (18-23), and four new C₂₁ steroids, 11α,12β-O-ditigloyl-tenacigenin C (24), 11α-O-benzoyl-12β-O-tigloyl-tenacigenin C (25), 11α-O-tigloyl-12β-O-benzoyl-tenacigenin C (26) and 11α-O-tigloyl-12β-O-benzoyl-marsdenin (27), were isolated from the Dai herbal medicine Dai-Bai-Jie, derived from the roots of Marsdenia tenacissima. The chemical structures of all compounds were established by spectroscopic techniques, including high-resolution mass spectrometry and NMR spectroscopy, as well as by comparison with reported spectral data. The anti-HIV activities of these compounds were screened, and the compounds obtained displayed inhibitory effects against HIV-1 with inhibition rates of 36.4-81.3% at 30 μM.

Effects of Marsdenia tenacissima polysaccharide on the immune regulation and tumor growth in H22 tumor-bearing mice

One water-soluble polysaccharide (Marsdenia tenacissima polysaccharide, MTP), with an average molecular weight of 4.9 × 10(4) Da, was isolated from the dried rattan of M. tenacissima. MTP contained 93.8% carbohydrates, 5.6% proteins and 21.3% uronic acid, and were composed of arabinose, mannose, galactose, xylose, glucuronic acid at a molar ratio of 9.1, 17.7, 30.2, 22.4 and 20.6. The experiments on the animals showed that MTP could increase the serum hemolysin, promote the formation of antibody-forming cells and improve the phagocytosis of mononuclear macrophage in normal mice. Meanwhile, MTP could also inhibit the growth of tumor in H22 tumor-bearing mice dose-dependently, and increase the spleen index, thymus index and serum albumin level in the mice. In addition, MTP could elevate the serum level of TNF-α and IL-2, increase the activity of GSH-Px, CAT and SOD in the liver tissue, and reduce the content of VEGF and MDA. These results suggest that MTP can regulate the immune function in mice and suppress the growth of tumor in H22 tumor-bearing mice, and its antitumor activity may be related to its antioxidant and immunomodulatory effects.