Transcriptome and metabolome analysis of the developmental changes in Cynanchum thesioides anther.

Cynanchum thesioides, a xerophytic species utilized both as a medicinal herb and a food source, plays a significant role in arid and desert ecosystem management. Its inflorescence is an umbellate cyme, each carrying nearly a thousand flowers; however, its fruiting rate remains remarkably low. The normal development of the anther is a necessary prerequisite for plants to produce seeds. However, our understanding of the anther development process in Cynanchum thesioides remains limited. To better understand the pollen development process in Cynanchum thesioides, the stages of pollen development were determined through paraffin sectioning, and observations were made on the distribution characteristics of polysaccharides and lipid droplets in the pollen development of Cynanchum thesioides using Periodic Acid-Schiff stain (PAS) and 0.5% Sudan Black B tissue staining. Concurrently, the gene expression patterns and metabolite profiles were delineated across various developmental stages of Cynanchum thesioides anthers (T1: microspore stage, T2: tetrad stage, T3: mononuclear stage, and T4: maturation stage). The findings revealed that Cynanchum thesioides pollen is in an aggregate form. Polysaccharides gradually accumulate during maturation and lipid droplets form a surrounding membrane, thereby preventing pollen dispersion. Furthermore, transcriptomic and metabolomic analyses across distinct developmental phases uncovered a plethora of differentially expressed genes and metabolites associated with the flavonoid biosynthesis pathway. Flavonoid levels exhibited dynamic changes concurrent with anther development, aligning with the gene regulatory patterns of the corresponding biosynthetic pathways. The study identified 63 differentially accumulated flavonoid compounds and 21 differentially expressed genes associated with flavonoid biosynthesis. Weighted gene co-expression network analysis revealed six MYB and ten bHLH transcription factors as key candidates involved in flavonoid biosynthesis, with CtbHLH (Cluster-6587.1050) and CtMYB (Cluster-6587.31743) specifically regulating structural genes within the pathway. These findings underscore the pivotal role of flavonoid biosynthesis in anther development of Cynanchum thesioides. In conclusion, this research offers a comprehensive insight into the anther development process in Cynanchum thesioides.

Jatrophihabitans cynanchi sp. nov., isolated from rhizosphere soil of Cynanchum wilfordii.

A novel actinobacterial strain, SB3-54T was isolated from rhizosphere soil of Cynanchum wilfodill, Jaecheon, Chungcheongbuk-do, Republic of Korea. Cells of strain SB3-54T were Gram-stain-positive, aerobic, rod-shaped, and flagellated which formed pale yellow colonies on Reasoner's 2A (R2A) agar. Growth occurred at 15-30 °C (optimum 25 °C), pH 5-8 (optimum pH 7), and 0-2.5% NaCl (optimum 0%). Phylogenetic and phylogenomic analyses showed that strain SB3-54T formed a separate lineage in the genus Jatrophihabitans with Jatrophihabitans telluris N237T. Strain SB3-54T was positive for catalase activity. Genomic analysis showed that SB3-54T has plant-beneficial function contributing (referred to as PBFC) genes such as root colonization and plant protection from oxidative stress. Furthermore, genome of SB3-54T contained gene clusters related to cytokinin biosynthesis, auxin response, tryptophan biosynthesis, siderophore biosynthesis and bacterial toxin-antitoxin systems. Strain SB3-54T contained iso-C16:0 as the major fatty acid and MK-9(H4) and MK-9(H6) as the predominant quinones. The organism had meso-diaminopimelic acid as the diagnostic diamino acid in the peptidoglycan. The major polar lipids were diphosphatidylglycerol, phosphatidylinositol polymannosides, two unidentified aminoglycophospholipids and three unidentified phospholipids. Based on phylogenetic, physiological and chemotaxonomic characteristics, strain SB3-54T represents a novel species of the genus Jatrophihabitans. The type strain is SB3-54T (= KCTC 49134T = NBRC 114108T).

Large herbivores suppress liana infestation in an African savanna.

African savannas are the last stronghold of diverse large-mammal communities, and a major focus of savanna ecology is to understand how these animals affect the relative abundance of trees and grasses. However, savannas support diverse plant life-forms, and human-induced changes in large-herbivore assemblages-declining wildlife populations and their displacement by livestock-may cause unexpected shifts in plant community composition. We investigated how herbivory affects the prevalence of lianas (woody vines) and their impact on trees in an East African savanna. Although scarce (<2% of tree canopy area) and defended by toxic latex, the dominant liana, Cynanchum viminale (Apocynaceae), was eaten by 15 wild large-herbivore species and was consumed in bulk by native browsers during experimental cafeteria trials. In contrast, domesticated ungulates rarely ate lianas. When we experimentally excluded all large herbivores for periods of 8 to 17 y (simulating extirpation), liana abundance increased dramatically, with up to 75% of trees infested. Piecewise exclusion of different-sized herbivores revealed functional complementarity among size classes in suppressing lianas. Liana infestation reduced tree growth and reproduction, but herbivores quickly cleared lianas from trees after the removal of 18-y-old exclosure fences (simulating rewilding). A simple model of liana contagion showed that, without herbivores, the long-term equilibrium could be either endemic (liana-tree coexistence) or an all-liana alternative stable state. We conclude that ongoing declines of wild large-herbivore populations will disrupt the structure and functioning of many African savannas in ways that have received little attention and that may not be mitigated by replacing wildlife with livestock.

Eucalyptol-loaded microcapsules combined with Cynanchum komarovii extracts provide long-term and low-risk management of Chinese wolfberry (Lycium barbarum L.).

Realizing eco-friendly, long-term, and low-risk aphid control on Lycium barbarum (medicinal cash crop) using a Cynanchum komarovii extracts and eucalyptus oil-loaded microcapsules (EOMCs) formulation compositions is viable. In this study, the aim is to optimize the composition of Cynanchum komarovii extracts and EOMCs formulation for effective control of aphids, the release of EOMCs was controlled by changing the cross-linking degree of the shell to match the aphid control characteristics of Cynanchum komarovii extracts. Four types of polyamines were used as cross-linking agents for the preparation of EOMCs by interfacial polymerization. The bioactivity, wettability, and field application efficacy of Cynanchum komarovii extracts and different EOMCs formulation compositions were evaluated. These EOMCs exhibited an encapsulation efficiency exceeding 85 %. The control efficiency of the formulation compositions of microcapsules with a moderate release rate and Cynanchum komarovii extracts on aphids remained at 62.86 %, while the control efficiency of the combination of microcapsules with the fastest and slowest rates with Cynanchum komarovii extracts was only 48.62 % and 57.11 %, respectively. The formulation compositions of Cynanchum komarovii extracts with all four types of EOMCs were found to be safe for Chinese wolfberry plants. Overall, by selecting appropriate polyamines during fabrication, the release rate can be effectively controlled to achieve sustainable and low-risk aphid control in Lycium barbarum through compounding with selected microcapsules.

Complete genome sequence of a novel polerovirus infecting Cynanchum rostellatum.

We detected a virus-like sequence in Cynanchum rostellatum leaves showing yellow mottle symptoms, found in Tokyo, Japan. RNA-Seq analysis revealed that the complete nucleotide sequence of the virus genome was 5,878 nucleotides in length and that it contained seven open reading frames (ORFs) specific to members of the genus Polerovirus. Accordingly, phylogenetic analysis revealed that the virus clustered with poleroviruses in the family Solemoviridae. The amino acid sequence identity values obtained by comparison of the deduced proteins of this virus and those of known members of the genus Polerovirus were lower than 90%, which is the species demarcation criterion of the taxon. The results indicate that this virus is a novel member of the genus Polerovirus, for which the name "cynanchum yellow mottle-associated virus" is proposed.

seco-Pregnane Glycosides from Australian Caustic Vine (Cynanchum viminale subsp. australe).

Cynanchum viminale subsp. australe, more commonly known as caustic vine, is a leafless succulent that grows in the northern arid zone of Australia. Toxicity toward livestock has been reported for this species, along with use in traditional medicine and its potential anticancer activity. Disclosed herein are novel seco-pregnane aglycones cynavimigenin A (5) and cynaviminoside A (6), together with new pregnane glycosides cynaviminoside B (7) and cynavimigenin B (8). Cynavimigenin B (8) contains an unprecedented 7-oxobicyclo[2.2.1]heptane moiety in the seco-pregnane series, likely arising from a pinacol-type rearrangement. Interestingly, these isolates displayed only limited cytotoxicity in cancer and normal human cell lines, in addition to low activity against acetylcholinesterase and Sarcoptes scabiei bioassays, suggesting that 5-8 are not associated with the reported toxicity of this plant species.

Cynasibirolide A, One New Humulanolide Sesquiterpene from Cynanchum acutum subsp. sibiricum.

Cynasibirolide A (1), one new humulanolide sesquiterpene, together with four known analogs, asteriscanolide (2), (1S,8S)-8-hydroxyhumula-2Z,6E,9E-trien-1,12-olide (3), (1S,7R)-8-oxohumula-2Z,9E-dien-1,12-olide (4), and (+)-6,7,9,10-tetrahydroasteriscunolide (5) were isolated from the roots and rhizomes of Cynanchum acutum subsp. sibiricum. Their structures and configurations were elucidated by spectroscopic methods, including 2D-NMR techniques, and the structure of 1 was confirmed by single-crystal X-ray diffraction. All compounds were evaluated for their anti-complementary activity in vitro, and compound 3 exhibited anti-complement effect with CH50 value of 0.45 mM.

Five New C21 -Steroidal Sapogenins from the Acid Hydrolysate of Cynanchum otophyllum Roots.

Five new C21 -steroidal sapogenins (1-5) named cynotogenins J-N, were isolated from the acid hydrolysate of Cynanchum otophyllum roots. Their structures were established by extensive spectroscopic analysis (UV, IR, HR-ESI-MS, and NMR). Most notably, compounds 1-3 harboring a rare 5ß,6ß-epoxy group in the C21 -steroidal skeleton of Cynanchum plants. All compounds were evaluated for their cytotoxicities against multiple cancer cell lines, in which compounds 5 showed weak cytotoxicity against HepG2 cancer cells with IC50 values of 44.90 µM.

Cynanotophyllosides E-F, two minor pregnane glycosides from the roots of cultivated Cynanchum otophyllum.

Cynanotophyllosides E-F, two new minor pregnane glycosides were isolated from the antidepressant active fraction of cultivated Cynanchum otophyllum, and their structures were determined as 12-O-vanilloyl-deacetylmetaplexigenin 3-O-ß-D-glucopyranosyl-(1→4)-ß-D-glucopyranosyl-(1→4)-ß-D-cymaropyranosyl-(1→4)-ß-D-oleandropyranosyl-(1→4)-ß-D-digitoxopyranoside, and 12-O-nicotinoyl-deacetylmetaplexigenin 3-O-ß-D-glucopyranosyl-(1→4)-ß-D-glucopyranosyl-(1→4)-ß-D-cymaropyranosyl-(1→4)-ß-D-oleandropyranosyl-(1→4)-ß-D-cymaropyranoside respectively, with the combination of spectroscopic and chemical analysis.

Two new pregnane glycosides from the root of Cynanchum auriculatum.

Two new pregnane glycosides (1 and 2), together with four known ones (3- 6), were isolated from the roots of Cynanchum auriculatum Royle ex Wight (Asclepiadaceae). On the basis of detailed spectroscopic analysis and chemical method, the structures of new compounds were characterized to be metaplexigenin 3-O-ß-D-cymaropyranosyl- (1→4)-α-L-diginopyranosyl-(1→4)-ß-D-cymaropyranoside (1), metaplexigenin 3-O-α-L-diginopyranosyl-(1→4)-ß-D-cymaropyranoside (2). All the isolated compounds (1-6) were tested for their in vitro inhibitory activity against the growth of human colon cancer cell lines HCT-116. Compounds 5 and 6 showed significant cytoxicities with IC50 values of 43.58 µM and 52.21 µM.

Genome structure and diversity among Cynanchum wilfordii accessions.

BACKGROUND: Cynanchum wilfordii (Cw) and Cynanchum auriculatum (Ca) have long been used in traditional medicine and as functional food in Korea and China, respectively. They have diverse medicinal functions, and many studies have been conducted, including pharmaceutical efficiency and metabolites. Especially, Cw is regarded as the most famous medicinal herb in Korea due to its menopausal symptoms relieving effect. Despite the high demand for Cw in the market, both species are cultivated using wild resources with rare genomic information. RESULTS: We collected 160 Cw germplasm from local areas of Korea and analyzed their morphological diversity. Five Cw and one Ca of them, which were morphologically diverse, were sequenced, and nuclear ribosomal DNA (nrDNA) and complete plastid genome (plastome) sequences were assembled and annotated. We investigated the genomic characteristics of Cw as well as the genetic diversity of plastomes and nrDNA of Cw and Ca. The Cw haploid nuclear genome was approximately 178 Mbp. Karyotyping revealed the juxtaposition of 45S and 5S nrDNA on one of 11 chromosomes. Plastome sequences revealed 1226 interspecies polymorphisms and 11 Cw intraspecies polymorphisms. The 160 Cw accessions were grouped into 21 haplotypes based on seven plastome markers and into 108 haplotypes based on seven nuclear markers. Nuclear genotypes did not coincide with plastome haplotypes that reflect the frequent natural outcrossing events. CONCLUSIONS: Cw germplasm had a huge morphological diversity, and their wide range of genetic diversity was revealed through the investigation with 14 molecular markers. The morphological and genomic diversity, chromosome structure, and genome size provide fundamental genomic information for breeding of undomesticated Cw plants.

Isolation and characterization of antioxidative monoterpenes from Cynanchum atratum roots.

One novel monoterpene rhamnoside (1) and 7 known monoterpenes (2-8) were isolated from the ethanol extract of Cynanchum atratum for the first time. Their structures were identified by comprehensive spectroscopic data analysis such as nuclear magnetic resonance, high-resolution electrospray ionization mass spectra, optical rotatory dispersion, and acid hydrolysis. In the subsequent antioxidant assay, compound 8 exhibited obvious 2,2-diphenyl-2-picrylhydrazyl hydrate radical scavenging activity.

Three New Pregnanes Isolated from the Cynanchum auriculatum.

Three new compounds named cynansteroid A (1), cynansteroid B (2) and cynansteroid C (3), together with nine known C21 -steroidal pregnane sapogenins (4-12) were isolated from the hydrolytic extract of the roots of Cynanchum auriculatum. The structures of cynansteroid A-C (1-3) were ascertained via the detailed analysis of the HR-ESI-MS, 1D and 2D NMR, and the calculated and experimental ECD data of cynansteroid B (2). Compound 11 displayed moderate inhibitory activity toward Verticillium dahliae Kleb (IC50 =37.15 µM), furthermore, compounds 11 and 12 showed significant inhibitory activity against Phomopsis sp. (IC50 =16.49 µM and 17.62 µM, respectively).

Twelve New Seco-Pregnane Glycosides from Cynanchum taihangense.

For our interest in the potential biologically active and structurally unique steroidal glycosides, continued phytochemical investigation of Cynanchum taihangense was carried out; twelve new seco-pregnane glycosides, cynataihosides I-L (1-4), M-T (7-14), and two known glycosides, glaucoside A (5) and atratcynoside F (6), were isolated from the 95% ethanol extract of Cynanchum taihangense. Two new aglycones were found among compounds 10, 11, 13, and 14. The structures of the glycosides were elucidated based on 1D and 2D NMR spectroscopic data, HR-ESI-MS analysis, and chemical evidence. The cytotoxicity of compounds against three human tumor cell lines (HL-60, THP-1, and PC-3) were evaluated by MTT assay. Compound 11 displayed significant cytotoxicity against THP-1 and PC-3 cell line with IC50 values of 5.08 and 22.75 µm, respectively. Compounds 3 and 14 exhibited moderate and selective cytotoxicity on HL-60 and THP-1 with IC50 values of 17.78 and 16.02 µm, respectively.

[Differences in intestinal absorption characteristics of Cynanchum auriculatum extract based on in situ intestinal circulation perfusion model in two states].

The present study aimed to investigate the intestinal absorption characteristics of six components(syringic acid, scopoletin, baishouwu benzophenone, caudatin, qingyangshengenin, and deacylmetaplexigenin) in Cynanchum auriculatum extract. In situ intestinal circulation perfusion model was employed to investigate the differences in intestinal absorption characteristics of C. auriculatum extract under the influence of different intestinal segments, different drug concentrations, and bile in the normal and functional dyspepsia(FD) states. The results showed that the absorption of baishouwu benzophenone decreased with the increase in the concentration of C. auriculatum extract(P<0.01), while the absorption of syringic acid and other components increased in a dose-independent manner, suggesting that baishouwu benzophenone might follow active absorption, while other components might not be on a single absorption pattern. The main absorption sites of each component in the normal state were different from those in the FD state. The cumulative absorption conversion rates in the FD state were generally lower than those in the normal state, and bile inhibited the absorption of other components except for scopoletin in both states(P<0.05). As revealed, the small intestine showed selectivity to the absorption of drugs, and the pathological state(such as FD) and bile both affected the absorption of the main components, which provides a theoretical basis for the development of new drugs and further development of C. auriculatum.

[Excretion of Cynanchum auriculatum extract in urine and feces of normal and functional dyspepsia rats].

In the present study, the excretion of four active components(qingyangshengenin, deacylmetaplexigenin, baishouwu benzophenone, and scopoletin) in Cynanchum auriculatum extract in the urine and feces of normal and functional dyspepsia(FD) rats was investigated. Rats were divided into a normal group and an FD model group. The FD model was induced by oral administration of ice hydrochloric acid combined with irregular feeding. The C. auriculatum extract was administered orally at a dose of 1 g·kg~(-1). The rat urine and feces were collected at 4, 8, 12, 24, 36, 48, 60, 72, and 84 h for UPLC-ESI-MS/MS analysis. The differences in excretion of the four components were compared between normal and FD rats. The results showed that except for the baishouwu benzophenone in the feces, the components such as qingyangshengenin in the urine and feces did not reach the plateau value within 84 h. Qingyangshengenin was mainly excreted through defecation, and the cumulative excretion rates in the normal state and FD were 0.32% and 0.66%, respectively. Deacylmetaplexigenin was mainly excreted through urination, and the cumulative excretion rates in the normal state and FD were 6.70% and 7.56%, respectively. Baishouwu benzophenone was mainly excreted through defecation in the normal state, but mainly excreted through urination in the FD state, with cumulative excretion rates of 0.41% and 0.52%, respectively. Scopoletin was mainly excreted through urination, with cumulative excretion rates of 0.83% and 2.13% in the normal state and FD, respectively. In general, the components were mainly excreted in the urine in the FD state. Compared with the normal group, the FD group showed decreased cumulative excretion rates of qingyangshengenin, baishouwu benzophenone, and scopoletin in the urine(P<0.05). Therefore, FD had a certain influence on the excretion of the main components of C. auriculatum extract, and the excretion of each component through urination and defecation was low, suggesting that there might be a wide range of metabolic pathways after oral administration and components were mainly excreted in the form of metabolites. This experiment provides a reference for the new drug development and clinical application of C. auriculatum.

[Intestinal absorption characteristics of root tuber of Cynanchum auriculatum extract in normal and functional dyspepsia model rats via everted intestine sac model].

The study investigated the difference of intestinal absorption characteristics of root tuber of Cynanchum auriculatum extract between normal and functional dyspepsia(FD) model rats with everted intestine sac model.The content of syringic acid, scopoletin, caudatin, baishouwu benzophenone, qingyangshengenin and deacyhmetaplexigenin in the C.auriculatum extract in different intestinal segments was detected by UPLC-MS/MS.The cumulative absorption amount(Q) and absorption rate constant(K_a) of the six chemical constituents were calculated.The results showed that the six components could be absorbed into the intestinal sac and were unsaturated, which indicated that the absorption mechanism of scopoletin was active transport in the intestine, while that of the other five components were passive diffusion.For normal group, the syringic acid and baishouwu benzophenone in ileum, qingyangshengenin and deacyhmetaplexigenin in ileum and duodenum, and caudatin in colon were well absorbed and scopoletin at low, medium and high concentrations was found excellent absorption in jejunum, ileum, and colon, respectively.Whereas the best absorption site of each component was ileum in model group.The absorption characteristics of each component between normal group and model group were complex at different concentrations, showing inconsistent tendency of absorption, which suggested that the components of root tuber of C.auriculatum extract were selectively absorbed in small intestine, and the absorption characteristics of the six components could be changed under FD status.This study provided theoretical basis for the clinical drug application and development of root tuber of C.auriculatum.

Influence of steroidal glycosides from Cynanchum auriculatum on antioxidant indicators in H2O2-damaged PC12 cells.

The root of Cynanchum auriculatum Royle ex Wight is a traditional Chinese medicine, which is rich in C21 steroidal glycosides by phytochemistry research. In this study, the antioxidant effect of 27 C21 steroidal glycosides isolated from the root of C. auriculatum by our group was evaluated using the H2O2-treated PC12 cells. As the result, all tested compounds altered the activities of lactate dehydrogenase, superoxide dismutase, catalase and glutathione peroxidase at concentrations as low as 1 µM in H2O2-treated PC12 cells. They also decreased the levels of intracellular reactive oxygen species and Ca2+. Further, the correlation between their structural features described by molecular descriptors and the indicators of bioactivity was analyzed by partial least squares analysis, displaying those six bio-indicators were positive correlated with 13 molecular descriptors and providing some guidance for further study of relationships between steroid structure and antioxidant activity.

Nocardioides cynanchi sp. nov., isolated from soil of rhizosphere of Cynanchum wilfordii.

A novel actinobacterial strain, SB3-45T, was isolated from soil of Cynanchum wilfordii rhizosphere, Jaecheon-si, Chungcheongbuk-do, Republic of Korea. Strain SB3-45T, was Gram-stain-positive, aerobic and coccoid to short rod-shaped bacterium. Growth occurred at 4-37 °C (optimum 28 °C), pH 5-8 (optimum pH 7) and 0-2.5 % NaCl (optimum 0%). Phylogenetic analysis based on 16S rRNA gene sequence showed that strain SB3-45T belonged to the genus Nocardioides and was closely related to Nocardioides opuntiae OS-21T (96.2%) and Nocardioides panacihumi Gsoil 616T (95.9%). ll-DAP as the diamino acid in the peptidoglycan and the menaquinone MK-8(H4) as the predominant isoprenoid quinone were detected. The polar lipids of strain SB3-45T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and unidentified phospholipid. The major cellular fatty acids (>5%) of strain SB3-45T were iso-C16 : 0, C18 : 1 ω9c and C17 : 0. Based on phylogenetic, physiological and chemotaxonomic characteristics, strain SB3-45T represents a novel species of the genus Nocardioides, for which the name Nocardioides cynanchi sp.nov. is proposed. The type strain is SB3-45T (=KCTC 49133T=NBRC 114107T).

Cynanchum auriculatum Royle ex Wight., Cynanchum bungei Decne. and Cynanchum wilfordii (Maxim.) Hemsl.: Current Research and Prospects.

Cynanchum auriculatum Royle ex Wight. (CA), Cynanchum bungei Decne. (CB) and Cynanchum wilfordii (Maxim.) Hemsl. (CW) are three close species belonging to the Asclepiadaceous family, and their dry roots as the bioactive part have been revealed to exhibit anti-tumor, neuroprotection, organ protection, reducing liver lipid and blood lipid, immunomodulatory, anti-inflammatory, and other activities. Until 2021, phytochemistry investigations have uncovered 232 compounds isolated from three species, which could be classified into C21-steroids, acetophenones, terpenoids, and alkaloids. In this review, the morphology characteristics, species identification, and the relationship of botany, extraction, and the separation of chemical constituents, along with the molecular mechanism and pharmacokinetics of bioactive constituents of three species, are summarized for the first time, and their phytochemistry, pharmacology, and clinical safety are also updated. Moreover, the direction and limitation of current research on three species is also discussed.