Cytotoxic constituents from the roots of Anthriscus sylvestris

Anthriscus sylvestris-Noxious Weed or Sustainable Source of Bioactive Lignans?

Anthriscus sylvestris (L.) Hoffm. (Apiaceae), commonly known as wild chervil, has gained scientific interest owing to its diverse phytochemical profile and potential therapeutic applications. The plant, despite being categorized as a noxious weed, is traditionally used in treating various conditions like headaches, dressing wounds, and as a tonic, antitussive, antipyretic, analgesic, and diuretic. Its pharmacological importance stems from containing diverse bioactive lignans, especially aryltetralins and dibenzylbutyrolactones. One of the main compounds of A. sylvestris, deoxypodophyllotoxin, among its wide-ranging effects, including antitumor, antiproliferative, antiplatelet aggregation, antiviral, anti-inflammatory, and insecticidal properties, serves as a pivotal precursor to epipodophyllotoxin, crucial in the semisynthesis of cytostatic agents like etoposide and teniposide. The main starting compound for these anticancer medicines was podophyllotoxin, intensively isolated from Sinopodophyllum hexandrum, now listed as an endangered species due to overexploitation. Since new species are being investigated as potential sources, A. sylvestris emerges as a highly promising candidate owing to its abundant lignan content. This review summarizes the current knowledge on A. sylvestris, investigating its biological and morphological characteristics, and pharmacological properties. Emphasizing the biological activities and structure-activity relationship, this review underscores its therapeutic potential, thus encouraging further exploration and utilization of this valuable plant resource.

Chemistry and Biological Activities of Naturally Occurring and Structurally Modified Podophyllotoxins

Plants containing podophyllotoxin and its analogues have been used as folk medicines for centuries. The characteristic chemical structures and strong biological activities of this class of compounds attracted attention worldwide. Currently, more than ninety natural podophyllotoxins were isolated, and structure modifications of these molecules were performed to afford a variety of derivatives, which offered optimized anti-tumor activity. This review summarized up to date reports on natural occurring podophyllotoxins and their sources, structural modification and biological activities. Special attention was paid to both structural modification and optimized antitumor activity. It was noteworthy that etoposide, a derivative of podophyllotoxin, could prevent cytokine storm caused by the recent SARS-CoV-2 viral infection.

Transcriptome analyses reveal the expression profile of genes related to lignan biosynthesis in Anthriscus sylvestris L. Hoffm. Gen

Anthriscus sylvestris L. Hoffm. Gen (A. sylvestris) is a perennial herb widely used for antitussive and diuretic purposes in traditional Korean and Chinese medicine. Lignans are critical secondary metabolites with widely pharmacological activities in A. sylvestris. Using transcriptome data of A. sylvestris, we identified genes related to lignan biosynthesis. In all, 123,852 unigenes were obtained from the flowers, leaves, roots, and stems of A. sylvestris with the Illumina HiSeq 4000 platform. The average length of unigenes was 1,123 bp and 91,217 (73.65%) of them were annotated in public databases. Differentially expressed genes and root-specific genes were analyzed between roots and the other three tissue types by comparing gene expression profiles. Specifically, the key enzyme genes involved in lignan biosynthesis were identified and analyzed. The expression levels of some of these genes were highest in the roots, consistent with the accumulation of deoxypodophyllotoxin. These expression levels were experimentally verified via quantitative real-time polymerase chain reaction (qRT-PCR). This research provides valuable information on the transcriptome data of A. sylvestris and the identification of candidate genes associated with the biosynthesis of lignans, laying the foundation for further research on genomics in A. sylvestris and related species.

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The online version contains supplementary material available at 10.1007/s12298-022-01156-w.

Comprehensive study of Anthriscus sylvestris lignans

Wild chervil (Anthriscus sylvestris) is a widespread, wild-growing herbaceous plant from Apiaceae family, known for high content of lignans related to podophyllotoxin, and thus representing a promising new source for their industrial isolation. The data on detailed chemical profile of A. sylvestris lignans are still lacking. By combining fractionation with non-targeted LC-DAD-ESI-MS/MS metabolite profiling, we have identified, fully or tentatively, 46 lignans, 12 of which were never reported in A. sylvestris and 19 in any biological source. The dominant lignans were found to be nemerosin, yatein, deoxypodophyllotoxin, podophyllotoxin, podophyllotoxone and guayadequiol. In addition to well-known dibenzylbutyrolactones, aryltetralins and 7-oxygenated aryltetralins, we found several oxygenated lignan classes previously undescribed in A. sylvestris - 7-hydroxy, 7-oxo and 8-hydroxydibenzylbutyrolactones, a 7'-oxotetrahydrofuran and a 7-hydroxyarylnaphthalene. To facilitate future rapid classification and identification of lignans in raw extracts, UV, MS and NMR spectral features of different lignan classes are described.

Bioactive C17 and C18 Acetylenic Oxylipins from Terrestrial Plants as Potential Lead Compounds for Anticancer Drug Development

Bioactive C₁₇ and C₁₈ acetylenic oxylipins have shown to contribute to the cytotoxic, anti-inflammatory, and potential anticancer properties of terrestrial plants. These acetylenic oxylipins are widely distributed in plants belonging to the families Apiaceae, Araliaceae, and Asteraceae, and have shown to induce cell cycle arrest and/or apoptosis of cancer cells in vitro and to exert a chemopreventive effect on cancer development in vivo. The triple bond functionality of these oxylipins transform them into highly alkylating compounds being reactive to proteins and other biomolecules. This enables them to induce the formation of anti-inflammatory and cytoprotective phase 2 enzymes via activation of the Keap1–Nrf2 signaling pathway, inhibition of proinflammatory peptides and proteins, and/or induction of endoplasmic reticulum stress, which, to some extent, may explain their chemopreventive effects. In addition, these acetylenic oxylipins have shown to act as ligands for the nuclear receptor PPARγ, which play a central role in growth, differentiation, and apoptosis of cancer cells. Bioactive C₁₇ and C₁₈ acetylenic oxylipins appear, therefore, to constitute a group of promising lead compounds for the development of anticancer drugs. In this review, the cytotoxic, anti-inflammatory and anticancer effects of C₁₇ and C₁₈ acetylenic oxylipins from terrestrial plants are presented and their possible mechanisms of action and structural requirements for optimal cytotoxicity are discussed.

De novo transcriptome analysis of needles of Thujopsis dolabrata var. hondae

Podophyllotoxin is a starting material of the semisynthetic anticancer medicines etoposide, teniposide, and etopophos. The major plant source of podophyllotoxin is rhizomes of Podophyllum hexandrum, which is a Himalayan endangered species; therefore, alternative sources of podophyllotoxin or bioproduction systems have been pursued to avoid exploiting this limited natural resource. In this paper, we report de novo transcriptome analysis of Thujopsis dolablata var. hondae, which accumulates the podophyllotoxin derivatives (deoxypodophyllotoxin and β-peltatin A methyl ether) in its needles. We analyzed transcriptomes of the T. dolablata var. hondae young needles to obtain the sequences that putatively encode O-methyltransferases, cytochrome P450s, and a 2-oxoglutarate dependent dioxygenase because these protein families are responsible for podophyllotoxin-related compound formation in P. hexandrum. The resulting transcriptomes contained considerable numbers of coding sequences classified into the three protein families. Our results are a genetic basis for identifying genes involved in the biosynthesis of podophyllotoxin and related compounds and also for future metabolic engineering of podophyllotoxin in heterologous hosts.

Cytotoxicity against Cholangiocarcinoma and HepG2 Cell Lines of Lignans from Hernandia nymphaeifolia

Eleven lignans (1-11) were isolated from the seed of Hernandia nymphaeifolia. Most of the lignans exhibited strong to moderate cytotoxicity against cholangiocarcinoma KKU-M156 and HepG2 cell lines. Compounds 4 and 8 showed cytotoxicity against the KKU-M156 cell line with IC50 values of 5.2 μ M (Emax 96%) and 5.4 (Emax 59%) μM, respectively. In the cases of cytotoxicity against the HepG2 cell line, compounds 2, 3, 4, and 8 showed cytotoxicity with IC50 values of 1.7 M (Emax 84%), 4.1 μM (Emax 74%), 4.5 μM (Emax 68%), and 5.2 μM (Emax 78%), respectively.

Ethnomedicinal, Phytochemical and Pharmacological Profile of Anthriscus sylvestris as an Alternative Source for Anticancer Lignans

Anthriscus sylvestris (L.) Hoffm. is a wild herbaceous plant common in most temperate regions. It has been used traditionally to treat headaches, as a tonic, as antitussive, antipyretic, analgesic and diuretic. The plant contains deoxypodophyllotoxin, which is proven to have antitumor and anti-proliferative effects, anti-platelet aggregation, antiviral, anti-inflammatory and insecticidal activity. Deoxypodophyllotoxin is considered to be the plant’s most important constituent, because of its pharmacological properties and because it can be converted into epipodophyllotoxin, the main raw material for the semisynthesis of the cytostatic agents etoposide and teniposide. This work summarizes for the first time the results related to the botanical description, distribution and habitat, phytochemical and pharmacological properties and emphasizes the aspects for future biotechnological research to establish its utility in the therapeutic arsenal.

Falcarindiol allosterically modulates GABAergic currents in cultured rat hippocampal neurons

Falcarindiol (1), a C-17 polyacetylenic diol, shows a pleiotropic profile of bioactivity, but the mechanism(s) underlying its actions are largely unknown. Large amounts of 1 co-occur in water hemlock (Oenanthe crocata) along with the convulsant polyacetylenic toxin oenanthotoxin (2), a potent GABA(A) receptor (GABA(A)R) inhibitor. Since these compounds are structurally and biogenetically related, it was considered of interest to evaluate whether 1 could affect GABAergic activity, and for this purpose a model of hippocampal cultured neurons was used. Compound 1 significantly increased the amplitude of miniature inhibitory postsynaptic currents, accelerated their onset, and prolonged the decay kinetics. This compound enhanced also the amplitude of currents elicited by 3 μM GABA and accelerated their fading, reducing, however, currents evoked by a saturating (10 mM) GABA concentration. Moreover, kinetic analysis of responses to 10 mM GABA revealed that 1 upregulated the rate and extent of desensitization and slowed the current onset and deactivation. Taken together, these data show that 1 exerts a potent modulatory action on GABA(A)Rs, possibly by modulating agonist binding and desensitization, overall potentially decreasing the toxicity of co-occurring GABA-inhibiting convulsant toxins.

Chemical Composition and Antimicrobial Activity of Anthriscus nemorosa Root Essential Oil

The essential oil obtained by hydrodistillation from the roots of Anthriscus nemorosa (Bieb.) Sprengel (Umbelliferae) was analyzed by GC and GC-MS. Among sixty-two compounds identified (representing 89.0% of the total oil), the main components were: n-nonane (12.1%), n-hexadecanol (6.9%), δ-cadinene (6.4%), β-pinene (6.0%) and germacrene D (5.4%). Furthermore, the antimicrobial activity of the oil was evaluated against the Gram-positive bacteria Staphylococcus epidermidis (ATCC 12228) and Bacillus subtilis (ATCC 6633), the Gramnegative bacterium Escherichia coli (ATCC 25922), and a yeast Candida albicans (ATCC 10259 and ATCC 24433) using the broth microdilution method.

[4-t-butylphenyl]-N-(4-imidazol-1-yl phenyl)sulfonamide (ISCK03) inhibits SCF/c-kit signaling in 501mel human melanoma cells and abolishes melanin production in mice and brownish guinea pigs

It is well known that c-kit is related to pigmentation as well as to the oncology target protein. The objective of this study was to discover a skin-whitening agent that regulates c-kit activity. We have developed a high-throughput screening system using recombinant human c-kit protein. Approximately 10,000 synthetic compounds were screened for their effect on c-kit activity. Phenyl-imidazole sulfonamide derivatives showed inhibitory activity on c-kit phosphorylation in vitro. The effects of one derivative, [4-t-butylphenyl]-N-(4-imidazol-1-yl phenyl)sulfonamide (ISCK03), on stem-cell factor (SCF)/c-kit cellular signaling in 501mel human melanoma cells were examined further. Pretreatment of 501mel cells with ISCK03 inhibited SCF-induced c-kit phosphorylation dose dependently. ISCK03 also inhibited p44/42 ERK mitogen-activated protein kinase (MAPK) phosphorylation, which is known to be involved in SCF/c-kit downstream signaling. However ISCK03 did not inhibit hepatocyte growth factor (HGF)-induced phosphorylation of p44/42 ERK proteins. To determine the in vivo potency of ISCK03, it was orally administered to depilated C57BL/6 mice. Interestingly, oral administration of ISCK03 induced the dose-dependent depigmentation of newly regrown hair, and this was reversed with cessation of ISCK03 treatment. Finally, to investigate whether the inhibitory effect of ISCK03 on SCF/c-kit signaling abolished UV-induced pigmentation, ISCK03 was applied to UV-induced pigmented spots on brownish guinea pig skin. The topical application of ISCK03 promoted the depigmentation of UV-induced hyperpigmented spots. Fontana-Masson staining analysis showed epidermal melanin was diminished in spots treated with ISCK03. These results indicate that phenyl-imidazole sulfonamide derivatives are potent c-kit inhibitors and might be used as skin-whitening agents.

Lignans and Coumarins from the Roots of Anthriscus sylvestris and Their Increase of Caspase-3 Activity in HL-60 Cells

A new lignan, sylvestrin (1), was isolated from the MeOH-soluble fraction of the roots of Anthriscus sylvestris HOFFM. (Umbelliferae), along with six lignans (2-7), three coumarins (8-10), and a polyacetylene (11). The structure of sylvestrin was determined to be 2-(3',4',5'-trimethoxybenzylidene)-3-(3'',4''-methylendioxybenzyl)-gamma-butyrolactone (1) by spectroscopic means, including 2D-NMR. The eleven compounds were assessed for their abilities to activate a caspase-3 in human promyeloid leukemic HL-60 cells. The intracellular caspase-3 activity of (-)-deoxypodophyllotoxin (3), angeloyl podophyllotoxin (5), deoxypicropodophyllin (6), picropodophyllotoxin (7), and falcarindiol (11) increased approximately 4.6, 3.6, 3.7, 3.9, and 3.9-fold, at 0.001, 1, 1, 1, and 20 microM, respectively, over that of the untreated control. In addition, compounds 3, 5, 6, and 7 showed apoptosis-inducing activities that were measured by DNA fragmentation in HL-60 cells.

A new furofuran lignan fromGeranium thunbergii Sieb. et Zucc

A new furofuran lignan, 4-hydroxykobusin (3), together with known lignans, kobusin (1), and 7,7'-dihydroxybursherenin (2), were isolated from the whole plant of Geranium thunbergii Sieb. et Zucc (Geraniaceae). The structures were determined based on the spectral data and a comparison with the published data. This is the first report of the presence of furofuran lignan in Geranium species.

7,7'-Dihydroxy bursehernin inhibits the expression of inducible nitric oxide synthase through NF-kappaB DNA binding suppression

This study isolated a lignan, 7,7'-dihydroxy bursehernin, from Geranium thunbergii and investigated whether or not the lignan affects the induction of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in RAW264.7 macrophages stimulated with lipopolysaccharide (LPS). The gel shift analysis and luciferase reporter gene assays using the iNOS promoter and nuclear factor-kappaB (NF-kappaB) minimal promoter showed that a treatment with 7,7'-dihydroxy bursehernin reduced the reporter activities and binding of NF-kappaB to the NF-kappaB consensus sequence, while it had no effect on the nuclear translocation of p65 and the phosphorylation/degradation of I-kappaBalpha. It was reported that a few natural compounds directly suppressed the binding activity of the NF-kappaB components to DNA. The NF-kappaB binding activity was not reversed by the in vitro exposure of the nuclear extracts to 7,7'-dihydroxy bursehernin, which suggest that a metabolite(s) of 7,7'-dihydroxy bursehernin might target the binding of the NF-kappaB complex to the DNA binding domain region in the promoter region of the iNOS gene. After incubation of RAW264.7 cells with 7,7-dihydroxy bursehernin for 18h, the levels of parent compound were negligible; while a main metabolite, 4-[4-(n-hydroxy-phenyl)-2,3-dimethyl-buta-1,3-dienyl]-benzene-1,2-diol was detected in cell lysates and culture medium.

Inhibition of skin pigmentation by an extract of Lepidium apetalum and its possible implication in IL-6 mediated signaling

The development of effective skin-lightening agents is an increasingly important area of research aimed at the treatment of hyperpigmentation induced by UV irradiation or by medical conditions such as melasma, postinflammatory melanoderma and solar lentigo. Although some inhibit tyrosinase, identifying and understanding the mechanisms of action of other agents is an important goal if more effective pigmentation inhibitors are to be developed. We present here that an extract of Lepidium apetalum (ELA) decreased UV-induced skin pigmentation in brown guinea pigs and melanogenesis of HM3KO human melanoma cells. Interestingly, ELA did not reduce melanogenesis in HM3KO cells unless they were co-cultivated in keratinocyte-conditioned medium prepared by culturing keratinocytes with ELA. Under these conditions, ELA decreased tyrosinase mRNA and protein expression as well as melanin content via an ELA-mediated increase in keratinocyte IL-6 production which in turn was shown to decrease in the expression Mitf, a transcription factor implicated in tyrosinase gene expression and melanocyte differentiation. The results reveal that ELA may be an effective inhibitor of hyperpigmentation caused by UV irradiation or by pigmented skin disorders through a mechanism involving IL-6-mediated downregulation of Mitf rather than a direct inhibition of tyrosinase activity.

Podophyllotoxin: distribution, sources, applications and new cytotoxic derivatives

Several podophyllotoxin derivatives modified in the A, B, C, D and E rings were prepared from podophyllotoxin and methyl isoxazopodophyllic acid and evaluated for their cytotoxicity on several neoplastic cell lines. Chemical transformations performed on these compounds have yielded derivatives more potent and more selective that the parent compound. Most of the compounds maintained their cytotoxicity at the microM level. Distribution, biosynthesis, production, biotechnology, applications and synthesis have also been reviewed.

Cytotoxic and cytostatic activity of erlangerins from Commiphora erlangeriana

The resin of Commiphora erlangeriana is known to be poisonous to humans and animals and has traditionally been used as an arrow poison. Since recent phytochemical studies on this plant material has identified four major lignans (named, Erlangerins A to D) that closely relate to the structure of podophyllotoxin, it was hypothesised that the well known poisoning effect of the resin could in part be due to direct toxicity to mammalian cells. Hence, the toxicity of Erlangerins was studied by measuring the viability of two human (HeLa and EAhy926) and two murine (L929 and RAW 264.7) cell lines. As assessed by the MTT assay, the effect of Erlangerin C and D closely follow the activity profile of podophyllotoxin: they induced a concentration-dependent cytotoxicity in the murine macrophage cells (RAW 264.7) and a cytostatic effect in HeLa, EAhy926 and L929 cells. In contrast, Erlangerins A and B suppressed cell viability at relatively higher concentrations (EC(50) values higher than 3 micro M as compared with nM concentration range for Erlangerins C and D and podophyllotoxin) and their activity appears to be consistent with a cytotoxic mode of action in all cell lines studied. The structure-activity-relationship established from the study is discussed.

Apoptosis induction of Persicae Semen extract in human promyelocytic leukemia (HL-60) cells

The major ingredient of Persicae Semen is a cynogenic compound, amygdalin (D-mandelonitrile-beta-gentiobioside). Controversial results on the anticancer activity of amygdalin were reported due to its conversion to its inactive isomer, neoamygdalin. In order to inhibit the epimerization of amygdalin, we used newly developed simple acid boiling method in preparation of Persicae Semen extract. HPLC analysis revealed most of amygdalin in Persicae Semen extract was active D-form. Persicae Semen extract was used to analyze its effect on cell proliferation and induction of apoptosis in human promyelocytic leukemia (HL-60) cells. Persicae Semen extract was cytotoxic to HL-60 cells with IC50 of 6.4 mg/mL in the presence of 250 nM of beta-glucosidase. The antiproliferative effects of Persicae Semen extract appear to be attributable to its induction of apoptotic cell death, as Persicae Semen extract induced nuclear morphology changes and internucleosomal DNA fragmentation.

Novel action of lignans isolated from Hernandia nymphaeifolia on Ca(2+) signaling in renal tubular cells

The effect of five lignans, epi-aschantin, epi-magnolin, epi-yangambin, deoxypodophyllotoxin and yatein, isolated from Hernandia nymphaeifolia on Ca(2+) signaling in Madin-Darby canine kidney cells was examined using fura-2 as a Ca(2+) indicator. These lignans at concentrations between 10 and 100 microM increased [Ca(2+)](i) in a concentration-dependent manner. Removal of extracellular Ca(2+) abolished the Ca(2+) signals evoked by 50 microM of the lignans. La(3+)(50 microM) abolished the Ca(2+) signals induced by 100 microM of epi-aschantin, epi-magnolin and epi-yangambin, and 20 microM deoxypodophyllotoxin, but inhibited by 60% 50 microM yatein-induced responses. All five lignans (50-100 microM) inhibited by 42-65% thapsigargin-induced capacitative Ca(2+) entry, and inhibited by 23-61% thapsigargin-induced intracellular Ca(2+) release. Epi-yangambin (100 microM), epi-magnolin (100 microM), and epi-aschantin (100 microM) inhibited by 8-38% 10 microM ATP-induced Ca(2+) release. Trypan blue exclusion revealed that incubation with deoxypodophyllotoxin or yatein (but not the other lignans) decreased cell viability in a concentration-dependent manner. Together, the results suggest that, in renal tubular cells, these lignans exert multiple actions on Ca(2+) signaling. They caused Ca(2+) influx but reduced thapsigargin-induced capacitative Ca(2+) entry and also thapsigargin- and ATP-induced Ca(2+) release. Additionally, deoxypodophyllotoxin and yatein may be cytotoxic.