Anti-inflammatory ent-cleistanthane-type diterpenoids from Phyllanthus rheophyticus.

A bioactivity-guided isolation from the aerial parts of Phyllanthus rheophyticus obtained 17 undescribed ent-cleistanthane-type diterpenoids, namely phyllarheophols A-Q, as well as 12 known analogs. Their structures were characterized by a combination of spectroscopic data interpretation, single-crystal X-ray diffraction and ECD analysis. The anti-inflammatory activities of these compounds were evaluated by measuring their inhibitory effects on NO production in LPS-stimulated RAW264.7 macrophages, and their preliminary structure-activity relationships were also discussed. Further study showed that promising compounds phyllarheophol D and phyacioid B significantly suppressed the expressions of cytokines and nitric oxide synthase through the NF-κB signaling pathway.

Diterpenoids with an unusual tricyclo[10.3.0.02,9]pentadecane skeleton from Pedilanthus tithymaloides as multidrug resistance modulators.

Three new diterpenoids with an unusual carbon skeleton, pedilanins A-C (1-3), and nine new jatrophane diterpenoids, pedilanins D-L (4-12), along with five known ones (13-17), were isolated from Pedilanthus tithymaloides. Compounds 1-3 characterize an unprecedented tricyclo[10.3.0.02,9]pentadecane skeleton. Compounds 4-8 are rare examples of the jatrophanes bearing a cyclic hemiketal substructure. Their structures were determined by an extensive analysis of HRESIMS, NMR, quantum-chemical calculation, DP4+ probability, and X-ray crystallographic data. In the bioassay, compounds 1-12 dramatically reversed multidrug resistance in cancer cells with the fold-reversals ranging from 17.9 to 396.8 at the noncytotoxic concentration of 10 µM. The mechanism results indicated that compounds 2 and 3 inhibited the P-glycoprotein (Pgp) transporter function, thus reversing the drug resistance.

Synthesis and discovery of Baylis-Hillman adducts as potent and selective thioredoxin reductase inhibitors for cancer treatment.

The selenoprotein thioredoxin reductase (TrxR) is of paramount importance in maintaining cellular redox homeostasis, and aberrant upregulation of TrxR is frequently observed in various cancers due to their elevated oxidative stress in cells. Thus, it seems promising and feasible to target the ablation of intracellular TrxR for the treatment of cancers. We report herein the design and synthesis of a series of Baylis-Hillman adducts, and identified a typical adduct that possesses the superior cytotoxicity against HepG2 cells over other types of cancer cells. The biological investigation shows the selected typical adduct selectively targets TrxR in HepG2 cells, which thereafter results in the collapse of intracellular redox homeostasis. Further mechanistic studies reveal that the selected typical adduct arrests the cell cycle in G1/G0 phase. Importantly, the malignant metastasis of HepG2 cells is significantly restrained by the selected typical adduct. With well-defined molecular target and mechanism of action, the selected typical adduct, even other Baylis-Hillman skeleton-bearing compounds, merits further development as candidate or ancillary agent for the treatment of various cancers.

Cardiac glycosides from Digitalis lanata and their cytotoxic activities.

Cardiac glycosides (CGs) are good candidates as drug leads in the treatment of cancer because of their structural diversities and potent biological activities. In this study, fifteen CGs including three new ones (1-3) were isolated from Digitalis lanata Ehrh. Their structures were elucidated by HRESIMS, NMR spectroscopic methods, including homonuclear and heteronuclear coupling constant analysis, and acid-catalyzed hydrolysis and derivatization analysis of the sugar chain. The cytotoxic activities of these CGs were evaluated against three human cancer cell lines (A549, HeLa and MCF-7 cell lines), and all of them showed strong activities at nanomolar scale. The flow cytometric analysis indicated that compound 1 induced cell cycle arrest in the G2/M phase. Transcriptome analysis revealed a panel of possible targets for compound 1. RT-PCR and western blot experiments showed that 1 significantly inhibited the expression of vasohibin-2 (VASH2). Moreover, compound 1 restrained angiogenesis in a concentration-dependent manner in the chick embryo chorioallantoic membrane (CAM) model.

Cytotoxic cardenolides from Calotropis gigantea.

Sixteen cardiac glycosides, including five previously undescribed compounds, were extracted and purified from whole plants of Calotropis gigantea (L.). Spectroscopic data and electronic circular dichroism (ECD) analyses were used to determine their structures. Calogiganin C is the first naturally occurring example of a cardenolide containing a 7-membered lactone in ring A. The cytotoxic activities of these compounds against A172, U251, AGS, PANC-1, HepG2, HCT116 and NCI-H226 cell lines were evaluated. Four of them exhibited the most potent growth inhibitory activity against a panel of human cancer cell lines, including A172, U251, AGS, PANC-1 and HCT116. Notably, uscharidin and calotropin showed pronounced cytotoxicities at low nanomolar concentrations against A172 and U251 cells, and possible cell death mechanism studies manifested that these two compounds induced G2/M cell cycle arrest, which demonstrated promising anticancer potential.

[Progress on wheat A genome illustration and its evolutional analysis].

Wheat is one of the main food crops and widely grown in the world. It feeds more than 35% of the world's population. Obtaining high-quality genome sequences of wheat is important for its basic and breeding researches. However, the large and complex genome of wheat once led to its genome sequencing as an "impossible task". Recently, with the development of high-throughput sequencing and assembly technology, many wheat genome sequences have been released, and their sequencing and assembly quality is being improved continuously. In the last two years, five wheat reference genomes with different ploidy levels have been published, including two diploid ancestors Triticum urartu (AA) and Aegilops tauschii (DD), wild and cultivated tetraploid wheat T. turgidum ssp. dicoccoides (BBAA) and hexaploid wheat T. aestivum (BBAADD). Among them, the sequencing and analysis of the T. urartu genome, a donor of polyploid wheat A subgenome, was led by the Institute of Genetics and Developmental Biology of the Chinese Academy of Sciences. In this review, we summarize the research progress on structure and evolution analyses of the T. urartu genome to provide some valuable information for promoting the basic and applied researches of wheat.

[Liver histological changes in chronic hepatitis B patients with elevated ALT less than 2 x ULN].

OBJECTIVE: To investigate the relevant factors of liver histological changes in chronic hepatitis B (CHB) patients with mildly elevated ALT and to explore the clinical values of these factors on anti-viral treatment. METHODS: A total of 152 CHB patients with mildly elevated ALT (less than 2 x ULN) who underwent liver biopsy were included in the study. Correlations between routine laboratory markers, liver histological inflammation grade and fibrosis stage were statistically assessed by Spearman correlation analysis, one-way ANOVA, area under the curve (AUC) of the receiver operating characteristic curves (ROC) and Logistic regression statistical analysis. RESULTS: All patients in the study showed various hepatic histological damages. Among the 152 patients 50 (32.9%) were found with inflammation grade 1 (G1), 42 (27.6%) with G2, 46 (30.3%) with G3 and 14 (9.2%) with G4. 16 patients (10.5%) were found with fibrosis stage 2 (S2), 25 (16.5%) with S3 and 41 (27.0%) with S4. Routine laboratory markers Alb, BPC and WBC were significantly correlated with hepatic histological inflammation grade and fibrosis stage. Marked liver fibrosis and moderate to severe liver damage were significantly higher in patients aged more than 40 years as compared to those less than 40 years of age (P = 0.002, P = 0.010). The regression equation P = 1/[1+e-(9.36250-1625Alb-0.0234BPC)] was established with sensitivity and specificity of 83.3% and 65.0%, respectively. CONCLUSION: 67.8% of CHB patients with mildly elevated ALT have significant injury to the liver tissue. CHB patients aged more than 40 years have a significant increase of marked liver fibrosis and moderate to severe liver damage. The regression equation is valuable to predict whether CHB patients need antiviral therapy or not.