Anti-proliferative and anti-inflammatory prenylated isoflavones and coumaronochromones from the fruits of Ficus altissima

Isoflavones isolated from the fruits of Ficus altissima and their anti-proliferative activities

Ficus altissima, also known as lofty fig, is a monoecious plant from the Moraceae family commonly found in southern China. In this study, we isolated and identified one new isoflavone (1), three new hydroxycoumaronochromones (2a, 2b and 3a) and 12 known compounds from the fruits of F. altissima. Their chemical structures were determined using spectroscopic analysis methods. We also tested all the isolated compounds for their anti-proliferative activities against eight human tumour cell lines (A-549, AGS, K562, K562/ADR, HepG2, HeLa, SPC-A-1 and CNE2) using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Our experiments showed that compound 6 exhibited obvious anti-proliferative activity against the K562 cell line with an IC50 value of 1.55 μM. Additionally, compounds 8 and 9 showed significant anti-proliferative activities against the AGS and K562 cell lines, respectively. Moreover, compound 6 induced apoptosis in K562 cells through the caspase family signalling pathway.

Potential of natural products in inflammation: biological activities, structure-activity relationships, and mechanistic targets

A balance between the development and suppression of inflammation can always be found in the body. When this balance is disturbed, a strong inflammatory response can damage the body. It sometimes is necessary to use drugs with a significant anti-inflammatory effect, such as nonsteroidal anti-inflammatory drugs and steroid hormones, to control inflammation in the body. However, the existing anti-inflammatory drugs have many adverse effects, which can be deadly in severe cases, making research into new safer and more effective anti-inflammatory drugs necessary. Currently, numerous types of natural products with anti-inflammatory activity and distinct structural features are available, and these natural products have great potential for the development of novel anti-inflammatory drugs. This review summarizes 260 natural products and their derivatives with anti-inflammatory activities in the last two decades, classified by their active ingredients, and focuses on their structure-activity relationships in anti-inflammation to lay the foundation for subsequent new drug development. We also elucidate the mechanisms and pathways of natural products that exert anti-inflammatory effects via network pharmacology predictions, providing direction for identifying subsequent targets of anti-inflammatory natural products.

Prenylated Flavonoids of the Moraceae Family: A Comprehensive Review of Their Biological Activities

Prenylated flavonoids (PFs) are natural flavonoids with a prenylated side chain attached to the flavonoid skeleton. They have great potential for biological activities such as anti-diabetic, anti-cancer, antimicrobial, antioxidant, anti-inflammatory, enzyme inhibition, and anti-Alzheimer's effects. Medicinal chemists have recently paid increasing attention to PFs, which have become vital for developing new therapeutic agents. PFs have quickly developed through isolation and semi- or full synthesis, proving their high value in medicinal chemistry research. This review comprehensively summarizes the research progress of PFs, including natural PFs from the Moraceae family and their pharmacological activities. This information provides a basis for the selective design and optimization of multifunctional PF derivatives to treat multifactorial diseases.

Anti-inflammatory monoterpenes from morinda (Morinda officinalis How.)

Morinda (Morinda officinalis How.) is widely consumed as a functional food owing to its potential to promote health. This study investigated the anti-inflammatory phytochemicals of morinda and isolated 30 monoterpenes, including 6 undescribed iridoids (1, 6, 9-11 and 25), 2 undescribed acyclic monoterpenoids (28, 29), a known acyclic monoterpenoid and 21 known iridoids. Their chemical and stereo-structures were elucidated based on HR-ESI-MS, NMR, 13C-NMR calculations, ECD data and ECD calculations. Notably, compounds 11, 12 and 20 exerted pronounced inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophages, with IC50 values of 28.51 ± 1.70, 25.45 ± 4.17 and 29.17 ± 3.71 μM respectively (indomethacin, IC50 of 33.68 ± 2.19 μM). The same compounds exert anti-inflammatory effects by blocking nuclear translocation of nuclear factor κ-B, and down-regulating the expression of inflammatory cytokines such as cyclooxygenase-2, inducible nitric oxide synthase, interleukin-1β and interleukin-6 at mRNA and protein levels in a dose-dependent manner. These results suggest that moderate consumption of morinda helps prevent and reduce the occurrence of inflammatory-related diseases.

Antiproliferative piperidine alkaloids from the leaves of Alocasia macrorrhiza

Seventeen piperidine alkaloids, including 15 previously undescribed 2-substituted-6-(9-phenylnonyl)-piperidine-3,4-diol alkaloids and a previously undescribed 2-substituted-6-(9-phenylnonyl)-piperidine-3-ol alkaloid, were isolated from the leaves of Alocasia macrorrhiza (L.) Schott. Their planar structures and configurations were elucidated based on HR-ESI-MS, 1D and 2D NMR, Snatzke's method, modified Mosher method, single-crystal X-ray crystallography, as well as quantum chemical calculation. It was found that ΔδH5b-H5a can be used to elucidate the relative configuration of 2,3,4,6-tetrasubstituted piperidine, by analyzing the NMR data of 2-substituted-6-(9-phenylnonyl)-piperidine-3,4-diol. Antiproliferative activity was evaluated for all of the alkaloids, and compounds 6-8 showed considerable inhibitory activity against K562 cell line, with the IC50 values of 17.24 ± 1.62, 19.31 ± 0.9 and 18.77 ± 1.09μM, respectively. Furthermore, compounds 6 and 7 exerted an antiproliferative effect by inducing apoptosis.

Eudesmane-type sesquiterpenoids from the aerial parts of Artemisia lavandulaefolia and their anti-pancreatic cancer activities

Five undescribed eudesmane sesquiterpenoids, artemilavanins A-E, and one undescribed rearranged eudesmane sesquiterpenoid, artemilavanin F, were isolated from the 95% ethanol extract of the aerial parts of Artemisia lavandulaefolia DC., along with ten known compounds. The structures and configurations of undescribed compounds were mainly elucidated by spectroscopic analyses and single-crystal X-ray diffraction analysis. Among all isolated compounds, artemilavanin F exhibited inhibitory activity on PANC-1 pancreatic cancer cells with IC50 of 9.69 ± 2.39 μM. Artemilavanin F inhibited PANC-1 cell proliferation by induction of G2/M cell cycle arrest and apoptosis mediated by downregulation of cyclin-dependent kinases and accumulation of reactive oxygen species. Moreover, artemilavanin F inhibited the colony formation, cell migration and sphere formation of PANC-1 cells, indicating the suppression of stem-cell-like phenotype of PANC-1 cells. Further results confirmed that the expression of cancer stem cell markers such as Bmi1, CD44, CD133 were inhibited by artemilavanin F. Downregulation of epithelial-mesenchymal transition (EMT) markers such as N-cadherin and Oct-4 indicated the potential of artemilavanin F in prevention of metastasis.

Phytochemistry and pharmacology of natural prenylated flavonoids

Prenylated flavonoids are a special kind of flavonoid derivative possessing one or more prenyl groups in the parent nucleus of the flavonoid. The presence of the prenyl side chain enriched the structural diversity of flavonoids and increased their bioactivity and bioavailability. Prenylated flavonoids show a wide range of biological activities, such as anti-cancer, anti-inflammatory, neuroprotective, anti-diabetic, anti-obesity, cardioprotective effects, and anti-osteoclastogenic activities. In recent years, many compounds with significant activity have been discovered with the continuous excavation of the medicinal value of prenylated flavonoids, and have attracted the extensive attention of pharmacologists. This review summarizes recent progress on research into natural active prenylated flavonoids to promote new discoveries of their medicinal value.

Anti-neuroinflammatory 3-hydroxycoumaronochromones and isoflavanones enantiomers from the fruits of Ficus altissima Blume

A phytochemical study on the fruits of Ficus altissima Blume (lofty fig) led to the isolation and structural elucidation of three pairs of enantiomeric 3-hydroxycoumaronochromones and two pairs of enantiomeric isoflavanones, including eight undescribed compounds. Their structures were determined based on a comprehensive analysis of NMR and HR-ESI-MS spectroscopic data, calculated ¹³C NMR-DP4 plus analysis and the comparisons of experimental measurements of ECD with calculated ECD spectra by TDDFT or ECD plots in reported protocols. The inhibitory effects of the isolated enantiomers on NO production stimulated by LPS in microglial BV-2 cells were evaluated. Among them, ficusaltin D exhibited the most potent anti-neuroinflammatory activity, which inhibited the production of NO and the expression of iNOS, IL-6 and IL-1β and suppressed the NF-κB nuclear translocation in LPS-induced BV-2 cells, while its enantiomer displayed cytotoxicity.

Comprehensive analysis of complete chloroplast genome and phylogenetic aspects of ten Ficus species

BACKGROUND

The large genus Ficus comprises approximately 800 species, most of which possess high ornamental and ecological values. However, its evolutionary history remains largely unknown. Plastome (chloroplast genome) analysis had become an essential tool for species identification and for unveiling evolutionary relationships between species, genus and other rank groups. In this work we present the plastomes of ten Ficus species.

RESULTS

The complete chloroplast (CP) genomes of eleven Ficus specimens belonging to ten species were determined and analysed. The full length of the Ficus plastome was nearly 160 kbp with a similar overall GC content, ranging from 35.88 to 36.02%. A total of 114 unique genes, distributed in 80 protein-coding genes, 30 tRNAs, and 4 rRNAs, were annotated in each of the Ficus CP genome. In addition, these CP genomes showed variation in their inverted repeat regions (IR). Tandem repeats and mononucleotide simple sequence repeat (SSR) are widely distributed across the Ficus CP genome. Comparative genome analysis showed low sequence variability. In addition, eight variable regions to be used as potential molecular markers were proposed for future Ficus species identification. According to the phylogenetic analysis, these ten Ficus species were clustered together and further divided into three clades based on different subgenera. Simultaneously, it also showed the relatedness between Ficus and Morus.

CONCLUSION

The chloroplast genome structure of 10 Ficus species was similar to that of other angiosperms, with a typical four-part structure. Chloroplast genome sizes vary slightly due to expansion and contraction of the IR region. And the variation of noncoding regions of the chloroplast genome is larger than that of coding regions. Phylogenetic analysis showed that these eleven sampled CP genomes were divided into three clades, clustered with species from subgenus Urostigma, Sycomorus, and Ficus, respectively. These results support the Berg classification system, in which the subgenus Ficus was further decomposed into the subgenus Sycomorus. In general, the sequencing and analysis of Ficus plastomes, especially the ones of species with no or limited sequences available yet, contribute to the study of genetic diversity and species evolution of Ficus, while providing useful information for taxonomic and phylogenetic studies of Ficus.

Antiproliferative Amaryllidaceae alkaloids from the bulbs of Hymenocallis littoralis (Jacq.) Salisb

Seven undescribed Amaryllidaceae alkaloids classified into four types, including the plicamine-type, secoplicamine-type, belladine-type and pretazettine-type, along with another three alkaloids that have not been isolated from plant material and seven known alkaloids, were isolated from the bulbs of Hymenocallis littoralis (Jacq.) Salisb. The structures were elucidated on the basis of various spectroscopic methods (UV, IR, MS, NMR, ECD). The isolated alkaloids were screened for antiproliferative activity against four human tumour cell lines (HepG2, HeLa, SPC-A-1, FaDu) through MTT assay, and some alkaloids exhibited potent cytotoxicity. Meanwhile, cell morphological assessment, flow cytometric analysis, Western blot analysis, clone formation and scratch wound assays were utilized for an undescribed belladine-type alkaloid and two known alkaloids, which had antiproliferative effects on the HepG2 cell line via induction of apoptosis in a dose-dependent manner. A pair of diastereoisomers of Amaryllidaceae alkaloids exhibited significant differences in antiproliferative activity. In addition, the alkaloids also possessed the potential to inhibit tumour cell migration.