Cevanine-type steroidal alkaloids from the bulbs of Fritillaria cirrhosa D. Don.

Eight previously undescribed cevanine-type steroidal alkaloids, cirrhosinones I-N and cirrhosinols A-B, along with five known analogs, were isolated from the bulbs of Fritillaria cirrhosa D. Don. Their structures were elucidated on the basis of comprehensive analysis of HRESIMS, 1D and 2D NMR spectroscopic data, and single-crystal X-ray diffraction analyses. All compounds revealed weak NO inhibitory activities in the LPS-stimulated NR8383 cells at the concentration of 20 µM, with inhibition ratios ranging from 5.1% to 14.3%.

Steroidal alkaloids and their glycosides from the bulbs of Fritillaria unibracteata.

Seven undescribed steroidal alkaloids, including two jervine-type steroidal alkaloids, fritiunibras A-B (1-2), and five cevanine-type steroidal alkaloid glycosides, fritiunibras C-G (3-7), along with six known cevanine-type steroidal alkaloids and their glycosides (8-13) were isolated from the bulbs of Fritillaria unibracteata Hsiao et K. C. Hsia. Their structures were determined by interpretation of comprehensive spectroscopic and single-crystal X-ray diffraction analysis. The absolute configurations of sugar moieties were determined by HPLC analysis and compared with standards after hydrolysis and derivatization. Furthermore, their inhibitory effects on NO production and cytotoxic activities were evaluated.

Impact of adding glucose-coated water-soluble silver nanoparticles to the silkworm larval diet on silk protein synthesis and related properties.

Biological modifications of the silk fibroin (silk) material have broad applications in textiles, biomedical materials and other industrial materials. It is economical to incorporate nanoparticles to the biosynthesis of silk fibroin by adding them to silkworm larval diets. This strategy may result in the rapid stable production of modified silk. Glucose-coated silver nanoparticles (AgNPs) were used to improve the AgNPs' biocompatibility, and the AgNPs were efficiently incorporated into silk by feeding. Larvae fed with AgNPs produced silk with significantly improved antibacterial properties and altered silk secondary structures. Both positive and negative effects on the growth and synthesis of silk proteins were observed after different AgNPs doses. Larvae feeding with low concentration of 0.02% and medium 0.20% AgNPs have greater transfer efficiencies of AgNPs to silk compared with feeding high concentration of 2.00% AgNPs. In addition, the elongation and tensile strength of the produced silk fibers were also significantly increased, with greater mammalian cell compatibility. The appropriate AgNPs concentration in the diet of silkworms can promote the synthesis of silk proteins, enhance their mechanical properties, improve their antibacterial property and inhibit the presence of Gram-negative bacteria.

Inhibition of MEK/ERK/STAT3 signaling in oleuropein treatment inhibits myocardial ischemia/reperfusion.

Studies have shown that oleuropein has antifungal, anti­inflammatory, antiviral, antioxidant, anticancer and hypoglycemic functions. TTC solution staining was used to measure myocardial infarction size. A commercial kit was used to measure lactate dehydrogenase (LDH), creatinine kinase­MB (CK­MB), tumor necrosis factor­α (TNF­α), interleukin­1ß (IL­1ß), IL 6, superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA) and catalase levels. Western blot analysis was used to measure p53, p-MEK p-ERK and p­IκBα protein expression. The present study reports that the protective effect of oleuropein also prevents against myocardial ischemia/reperfusion (myocardial I/R). The aim of this retrospective study was to evaluate this protective effect of oleuropein and the mechanisms by which myocardial I/R is prevented. Oleuropein inhibited myocardial infarction size, CK­MB and LDH serum levels in a myocardial I/R rat model. Moreover, oleuropein also attenuated caspase­3 activity, and p53, phosphorylated (p)­mitogen­activated protein kinase kinase (MEK), p­extracellular signal­regulated protein kinase (ERK) and p­IκBα protein expression. TNF­α, IL­1ß, IL­6 and MDA were decreased; SOD, GSH and catalase levels inhibited TNF­α, IL­1ß, IL-6 and MDA levels, and increased SOD, GSH and catalase levels in myocardial I/R rats treated with oleuropein. Rats orally administered the MEK inhibitor PD0325901, in addition to oleuropein, exhibited inhibited myocardial infarction size, CK­MB and LDH serum levels compared with rats treated with oleuropein only. Rats treated with MEK inhibitor also exhibited suppressed caspase­3 activity, p53, p­MEK p­ERK and p­IκBα protein expression, TNF­α, IL­1ß, IL­6, SOD, GSH, MDA and catalase levels, and induced p­signal transducer and activator of transcription 3 (STAT3) protein expression compared with rats treated with oleuropein only. Taken together, these results suggest that MEK/ERK/STAT3 signaling regulates the inhibition of myocardial I/R in rats treated with oleuropein.

Reproductive toxicity and gender differences induced by cadmium telluride quantum dots in an invertebrate model organism.

Sexual glands are key sites affected by nanotoxicity, but there is no sensitive assay for measuring reproductive toxicity in animals. The aim of this study was to investigate the toxic effects of cadmium telluride quantum dots (CdTe-QDs) on gonads in a model organism, Bombyx mori. After dorsal vein injection of 0.32 nmol of CdTe-QDs per individual, the QDs passed through the outer membranes of gonads via the generation of ROS in the membranes of spermatocysts and ovarioles, as well as internal germ cells, thereby inducing early germ cell death or malformations via complex mechanisms related to apoptosis and autophagy through mitochondrial and lysosomal pathways. Histological observations of the gonads and quantitative analyses of germ cell development showed that the reproductive toxicity was characterized by obvious male sensitivity. Exposure to QDs in the early stage of males had severe adverse effects on the quantity and quality of sperm, which was the main reason for the occurrence of unfertilized eggs. Ala- or Gly-conjugated QDs could reduce the nanotoxicity of CdTe-QDs during germ cell development and fertilization of their offspring. The results demonstrate that males are preferable models for evaluating the reproductive toxicity of QDs in combined in vivo/in vitro investigations.

[Block effects of BDNF antibody on MEK expression in lung of rats with brain ischemia].

UNLABELLED: OBJECITVE: To explore the block effect of brain-derived neurotrophic factor (BDNF) antibody on the mitogen extracellular kinase (MEK) expression in lung tissues of rats with brain ischemia. METHODS: Adult SD rats were divided into sham group, brain ischemia lung injury (BILI) group, and BDNF antibody treated group. Lung tissues were harvested at 3 days after operation. The distribution of MEK in the lung tissue was studied by immunhistochemistry, and the optical density values of MEK immunostaining was used to compare the difference of each group (n=5). RT-PCR was used to determine the block effect of BDNF antibody on the level of MEK mRNA (n=8). RESULTS: Immunohistochemistry showed that MEK immunoreactive positive products were observed in endothelia cells of airway and blood vessels. The optical density value in rats with brain ischemia significantly increased, compared with sham one (P<0.05). Moreover, BDNF antibody block could reverse this increase of BDNF immunostaining intensity (P<0.05). RT-PCR showed that BDNF antibody block significantly decreased the expressional level of MEK mRNA in the lung tissues with brain ischemia (P<0.05). CONCLUSION: BDNF antibody block leads to a significant reduction of MEK expression in endothelia cells of lung tissue in the rats with brain ischemia.