The saponin DT-13 Attenuates Tumor Necrosis Factor-α-induced Vascular Inflammation Associated with Src/NF-кB/MAPK Pathway Modulation

This study aimed to explore the effect of DT-13 (25(R,S)-ruscogenin- 1-O- [β-d-glucopyranosyl- (1→2)][β-d-xylopyranosyl-(1→3)]-β -d- fucopyranoside) on tumor necrosis factor (TNF)-α-induced vascular inflammation and the potential molecular mechanisms. In vitro, DT-13 suppressed TNF-α-induced adhesion and migration of human umbilical vein endothelial cells (HUVECs) by inhibiting the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). DT-13 markedly suppressed NF-кB p65 phosphorylation, and when NF-кB p65 was over-expressed, the inhibitory effect of DT-13 on adhesion molecular decreased. DT-13 also suppressed TNF-α induced luciferase activities of ICAM-1 and VCAM-1 promoter containing NF-κB binding sites. Furthermore, DT-13 markedly suppressed p38 phosphorylation and Src degradation induced by TNF-α, whereas had no significant effect on ERK and JNK activation. In vivo, DT-13 at 4 mg/kg prevented vascular inflammation and the expression of adhesion molecules induced by TNF-α in mice. These findings suggest that DT-13 abrogates vascular inflammation by down-regulating adhesion molecules associated with modulating the NF-кB, p38MAPK, Src signaling pathways, and NF-κB binding site is at least one of the targets of DT-13. This study provides novel information regarding the mechanism by which DT-13 exerts its effects on vascular inflammation, which is important for the onset and progression of various diseases.     

Genetic diversity and population structure of a cyprinid fish (Ancherythroculter nigrocauda) in a highly fragmented river

In this study, samples of Ancherythroculter nigrocauda, an endemic fish in the upper Yangtze River, were collected above and below dams in the Longxi River, a tributary of the upper Yangtze River, China, to investigate the genetic impacts of dams. The mitochondrial cytochrome b gene (cyt b) and 13 microsatellite (SSR) loci were used to analyze whether dams have resulted in loss of genetic diversity of the two fragmented populations or caused genetic differentiation between them. The results showed that the haplotype diversity (0.488; 0.486), nucleotide diversity (0.084%; 0.082%) and average expected heterozygosity (0.652; 0.676) of the two populations were all at a low level, and recent bottlenecks were detected. However, there was no genetic differentiation detected by the low genetic differentiation index (F_st, cyt b: ?0.1677, p = 0.99707; SSR: 0.00259, p = 0.81427). Besides, 11 pairs of half‐sibling relationship were found between the two populations indicating that there were individual movements and gene flow between them. This could be the larvae moving from upstream to downstream when water spilled over dams in flooding season. Therefore, our analysis showed that the dams have caused a loss of genetic diversity of the populations of A. nigrocauda in the Longxi River, blocked the active upstream movement but allowing passive downstream drift of larvae.     

Association of MCP-1 promoter polymorphism with susceptibility to nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is prevalent among populations from southern China and is influenced by both genetic and environmental risk factors. The monocyte chemoattractant protein-1 (MCP-1), a member of cysteine-cysteine chemokine family, plays critical roles in cancers. A polymorphism within the MCP-1 promoter, rs1024611, has been shown to be significantly associated with the risk of several cancers. Our purpose was to assess the role of rs1024611 in NPC susceptibility. By polymerase chain reaction-restriction fragment length polymorphism method, we genotyped rs1024611 in 593 patients with NPC (cases) and 480 cancer-free subjects (controls) among Guangxi population from southern China. We observed that the G allele of rs1024611 was significantly associated with the increased risk of NPC in an additive model and dominant model, respectively (P = 0.018 and 0.010, odds ratio = 1.25 and 1.41, respectively). No appreciable variation of the effects was found across the subgroups stratified by age, sex, nationality, smoking and drinking status, and smoking level. In addition, significantly higher messenger RNA (mRNA) expression level of MCP-1 was observed in NPC tissues than that in normal nasopharyngeal tissues, and the G allele of rs1024611 was significantly associated with elevated mRNA expression level of MCP-1 in Epstein-Barr virus-transformed lymphocytes. In conclusion, our findings suggested that rs1024611 at the MCP-1 promoter may be a risk factor for NPC. Further studies with larger sample size are necessary to confirm these findings.     

The biological activities of prothioconazole enantiomers and their toxicity assessment on aquatic organisms

Chiral fungicide prothioconazole has a wide range of antifungal spectrum; however, little research has been conducted to evaluate prothioconazole on an enantiomeric level. Five target pathogens and three common aquatic organisms were tested for the enantioselective bioactivity and toxicity of prothioconazole in this work. The antifungal activity of the enantiomers against wheat phytoalexin, rice blast fungus, exserohilum turcicum, Alternaria triticina, and Fusarium avenaceum was determined, and it was found that (?)‐prothioconazole were 85 to 2768 times more active than (+)‐prothioconazole toward these target organisms. In order to reflect the risk to aquatic ecosystem, the acute toxicity of the enantiomers to Daphnia magna, Chlorella pyrenoidosa, and Lemna minor L. was assessed. It was observed that the toxicity of (?)‐prothioconazole to D. magna was 2.2 times higher than (+)‐prothioconazole, but it was lower to C. pyrenoidosa and L. minor L. The toxicities of (+)‐enantiomer and (?)‐enantiomer to D. magna and C. pyrenoidosa were synergy, indicating that the racemate had higher threat to the organisms. It could be concluded that the effects of prothioconazole on target organisms and the acute toxicity to nontarget species were enantioselective with (?)‐enantiomer possessing higher efficiency and lower toxicity. Such enantiomeric differences should be taken into consideration when assessing the performance of prothioconazole.     

Relationship between exposure to an insecticide and fluctuating asymmetry in a damselfly (Odonata,Coenagriidae)

In this study, we explored the effects of pesticide on fluctuating asymmetry (FA) levels and mortality of Ceriagrion sp. larvae. The results showed that the mortality of larval damselflies treated with pesticide was significantly higher than that treated with tap water which had been aerated for 48 h, but there were no significant differences among mortality of larvae treated with different concentrations of pesticide. Meanwhile, we found that the level of FA of the first tibia length, one of the seven bilaterally symmetrical traits (First femur length, First tibia length, Second femur length, Second tibia length, Third femur length, Third tibia length and Prementum width), differed significantly with different treatments, whereas the others did not show any significant differences. The Bonferroni (Dunn) t Tests revealed that FA of the first tibia length at 15 × 10⁻⁹ mgl⁻¹ was significantly higher than that at 1.5 × 10⁻⁹ mgl⁻¹ and control. There was no significant relationship between trait size and the absolute difference between their right and left sides. There was also no significant relationship between body size and the absolute difference between right and left sides. Trait size was significantly positively correlated with body size. FA was not associated with mortality. Therefore, we concluded that FA of the first tibia length of Ceriagrion sp. larvae may be induced by sublethal doses of pesticides. That is to say, its FA may be regarded as an indicator of reflecting the level of pesticide stress. Handling editor: K. Martens     

Efficient <Emphasis Type="Italic">Agrobacterium tumefaciens</Emphasis>-mediated transformation using embryogenic suspension cultures in sweetpotato, <Emphasis Type="Italic">Ipomoea batatas</Emphasis> (L.) Lam.

Efficient Agrobacterium tumefaciens-mediated transformation was achieved using embryogenic suspension cultures of sweetpotato (Ipomoea batatas (L.) Lam.) cv. Lizixiang. Cell aggregates from embryogenic suspension cultures were cocultivated with the A. tumefaciens strain EHA105 harboring a binary vector pCAMBIA1301 with gusA and hygromycin phosphotransferase II gene (hpt II) genes. Selection culture was conducted using 25 mg l⁻¹ hygromycin. A total of 2,218 plants were regenerated from the inoculated 1,776 cell aggregates via somatic embryogenesis. β-glucuronidase (GUS) assay and PCR, dot blot and Southern blot analyses of the regenerated plants randomly sampled showed that 90.37% of the regenerated plants were transgenic plants. The number of integrated T-DNA copies varied from 1 to 4. Transgenic plants, when transferred to soil in a greenhouse and a field, showed 100% survival. No morphological variations were observed in the ex vitro transgenic plants. These results exceed all transformation experiments reported so far in the literature in quantity of independent events per transformation experiment in sweetpotato.     

Phytochrome chromophore deficiency leads to overproduction of jasmonic acid and elevated expression of jasmonate-responsive genes in Arabidopsis

An Arabidopsis mutant line named hy1-101 was isolated because it shows stunted root growth on medium containing low concentrations of jasmonic acid (JA). Subsequent investigation indicated that even in the absence of JA, hy1-101 plants exhibit shorter roots and express higher levels of a group of JA-inducible defense genes. Here, we show that the hy1-101 mutant has increased production of JA and its jasmonate-related phenotype is suppressed by the coi1-1 mutation that interrupts JA signaling. Gene cloning and genetic complementation analyses revealed that the hy1-101 mutant contains a mutation in the HY1 gene, which encodes a heme oxygenase essential for phytochrome chromophore biosynthesis. These results support a hypothesis that phytochrome chromophore deficiency leads to overproduction of JA and activates COI1-dependent JA responses. Indeed, we show that, like hy1-101, independent alleles of the phytochrome chromophore-deficient mutants, including hy1-100 and hy2 (CS68), also show elevated JA levels and constant expression of JA-inducible defense genes. We further provide evidence showing that, on the other hand, JA inhibits the expression of a group of light-inducible and photosynthesis-related genes. Together, these data imply that the JA-signaled defense pathway and phytochrome chromophore-mediated light signaling might have antagonistic effects on each other.     

Autophagy inhibition‐enhanced assembly of the NLRP3 inflammasome is associated with cisplatin‐induced acute injury to the liver and kidneys in rats

The nucleotide‐binding oligomerization domain‐like receptor family, pyrin domain containing 3 (NLRP3) inflammasome has a key role in the inflammatory response. We found that cisplatin (7.5, 15 mg/kg, IV) could induce acute injury to the liver and kidneys of rats. Western blot and immunohistochemical analyses showed that expression of NLRP3, caspase‐1 and interleukin‐1β was upregulated significantly in a dose‐dependent manner after cisplatin exposure. Autophagy could inhibit NLRP3 expression and assembly of the NLRP3 inflammasome. Expression of light chain 3 II/I and p62 suggested that autophagy was inhibited during injury to the liver and kidneys. These data suggested that cisplatin might activate NLRP3 by inhibiting autophagy in the liver and kidneys of rats.     

Interfacial Super‐Assembled Porous CeO2/C Frameworks Featuring Efficient and Sensitive Decomposing Li2O2 for Smart Li–O2 Batteries

The Li–O₂ battery (LOB) represents a promising candidate for future electric vehicles owing to its outstanding energy density. However, the practical application of LOB cells is largely blocked by the poor cycling performance of cathode materials. Herein, an ultralong 440‐cycle life of an LOB cell is achieved using CeO₂ nanocubes super‐assembled on an inverse opal carbon matrix as the cathode material without any additives. CeO₂ is proved to be effective for the complete and sensitive decomposition of loosely stacked Li₂O₂ films during the oxygen evolution reaction process and full accommodation of volume changes caused by the fast growth of Li₂O₂ films during the oxygen reduction reaction process. The super‐assembled porous CeO₂/C frameworks satisfy critical requirements including controlled size, morphology, high Ce³⁺/Ce⁴⁺ ratio, and efficient volume change accommodation, which dramatically increase the cycle life of LOB cell to 440 cycles. This study reveals the design strategy for high performance CeO₂ catalyst cathodes for LOB cells and the generation mechanisms of Li₂O₂ films during the discharge process by using density functional theory calculations, showing new avenues for improving the future smart design of CeO₂‐based cathode catalysts for Li–O₂ batteries.