Evaluation on the effect of hydrogen sulfide on the NLRP3 signaling pathway and its involvement in the pathogenesis of atherosclerosis.

BACKGROUND: As a common disease, the incidence of atherosclerosis (AS) in the world is high. Therefore, we aimed to evaluate the involvement of hydrogen sulfide (H 2 S)/cystathionine γ-lyase (CSE) in the pathogenesis of AS as well as their possible signaling pathways. METHODS: Enzyme-linked immunosorbent assay, real-time polymerase chain reaction, and Western blot analysis were used to detect the effect of CSE on the expression of inflammatory cytokines, ie, H 2 S, thioredoxin-interacting protein (TXNIP), NLRP3, apoptosis-associated speck-like protein (ASC), caspase-1, and interleukin (IL)-1ß. In addition, immunohistochemistry and Western blot analysis were performed to detect the levels of TXNIP, NLRP3, ASC, caspase-1, IL-1ß, and IL-18 among different groups. RESULT: Knockdown of CSE by the transfection of CSE small interfering RNA upregulated the levels of two inflammatory cytokines, ie, IL-1ß and IL-18. In addition, the downregulation of CSE promoted the expression of TXNIP, NLRP3, ASC, caspase-1, and IL-1ß in THP-1 cells. Meanwhile, treating the cells with sodium hydrosulfide (NaHS) inhibited the productions of IL-1ß and IL-18. Furthermore, upregulation of H 2 S synthesis by treating the cells with NaHS also reduced the protein levels of TXNIP, NLRP3, ASC, caspase-1, and IL-1ß. Finally, the protein levels of TXNIP and NLRP3 in the AS group were much higher than those in the AS + H 2 S group, which in turn was higher than the sham group. In addition, the AS group displayed the highest protein levels of TXNIP, NLRP3, ASC, caspase-1, IL-1ß, and IL-18, while the levels of these proteins in the AS + H 2 S group were higher than those in the sham group. CONCLUSION: In summary, the present finding suggested a possible linkage between H 2 S metabolism and AS through the H 2 S/CSE-TXNIP-NLRP3-IL-18/IL-1ß-nitric oxide (NO) signaling pathway.

miR­140­5p inhibits human glioma cell growth and invasion by targeting JAG1.

miR­140­5p has been reported to be a tumor suppressor in several types of human cancer, however, little is known about its expression and function in human gliomas. The present study aimed to detect the expression of miR­140­5p in human glioma tissues and cell lines, and to investigate the effect of miR­140­5p on glioma cell growth, invasion and adhesion using in vitro gain­of­function and loss­of­function experiments. Furthermore, the hypothesis that Jagged1 (JAG1) may be a target gene of miR­140­5p was tested. Reverse transcription­quantitative polymerase chain reaction analysis revealed that miR­140­5p was significantly downregulated in human glioma tissues and cell lines compared with normal tissues, and that its expression was correlated with the grade of gliomas. Transfection of a miR­140­5p mimic into SW1783 glioma cells promoted cell growth, invasion and adhesion, as determined by MTT, Transwell and cell adhesion assays respectively. By contrast, transfection of a miR­140­5p inhibitor had the opposite effect. A dual­luciferase reporter assay confirmed that JAG1 was a target gene of miR­140­5p, and miR­140­5p inhibited JAG1 expression both at the mRNA and protein level. In addition, JAG1 overexpression reversed the effect of miR­140­5p on glioma cell growth, invasion and adhesion. In conclusion, the present study is the first to reveal that miR­140­5p acts as a tumor suppressor in human gliomas. JAG1 was demonstrated to be a novel target of miR­140­5p, and miR­140­5p exerted its inhibitory effect on human glioma growth and invasion, partly by suppressing JAG1. The present study may provide useful information toward novel targets for the treatment of gliomas.

Analysis of promoters of microRNAs from a Glycine max degradome library.

OBJECTIVE: MicroRNAs (miRNAs) are genome-encoded, small non-coding RNAs that play important functions in development, biotic and abiotic stress responses, and other processes. Our aim was to explore the regulation of miRNA expression. METHODS: We used bioinformatics methods to predict the core promoters of 440 miRNAs identified from a soybean (Glycine max) degradome library and to analyze cis-acting elements for 369 miRNAs. RESULTS: The prediction results showed that 83.86% of the 440 miRNAs contained promoters in their upstream sequences, and 8.64% (38 loci) in their downstream sequences. The distributions of two core promoter elements, TATA-boxes and transcription start sites (TSSs), were similar. The cis-acting elements were examined to provide clues to the function and regulation of spatiotemporal expression of the miRNAs. Analyses of miRNA cis-elements and targets indicated a potential auxin response factor (ARF)- and gibberellin response factor (GARF)-mediated negative feedback loop for miRNA expression. CONCLUSIONS: The features of miRNAs from a Glycine max degradome library obtained here provide insights into the transcription regulation and functions of miRNAs in soybean.

Borrelidin, a potent antifungal agent: insight into the antifungal mechanism against Phytophthora sojae.

Borrelidin has high and specific antifungal activity against Phytophthora sojae . To explore the antifungal mechanism of borrelidin against P. sojae , the relationship between the antifungal activity of borrelidin and the concentration of threonine was evaluated. The results demonstrated that the growth-inhibitory effect of borrelidin on the growth of P. sojae was antagonized by threonine in a dose-dependent manner, suggesting that threonyl-tRNA synthetase (ThrRS) may be the potential target of borrelidin. Subsequently, the inhibition of the enzymatic activity of ThrRS by borrelidin in vitro was confirmed. Furthermore, the detailed interaction between ThrRS and borrelidin was investigated using fluorescence spectroscopy and circular dichroism (CD), implying a tight binding of borrelidin to ThrRS. Taken together, these results suggest that the antifungal activity of borrelidin against P. sojae was mediated by inhibition of ThrRS via the formation of the ThrRS-borrelidin complex.

Antifungal activity of borrelidin produced by a Streptomyces strain isolated from soybean.

In this study, an endophytic Streptomyces sp. neau-D50 with strong antifungal activity against Phytophthora sojae was isolated from healthy soybean root, using an in vitro screening technique. A bioactivity-guided approach was then employed to isolate and determine the chemical identity of bioactive constituents with antifungal activity from strain neau-D50. The structure of the antifungal metabolite was elucidated as borrelidin on the basis of spectral analysis. To our knowledge, this is the first report that borrelidin has strong antifungal activity against dominant race 1 of P. sojae with EC(50) and EC(95) of 0.0056 and 0.026 mg/L, respectively. The values were respectively 62.5- and 262.3-fold lower than those of the commercial fungicide metalaxyl, which has been used to treat soybean seed for the control of P. sojae . The in situ bioassays demonstrated that borrelidin at 10 mg/L reduced P. sojae race 1 lesions on soybean seedlings by 94.72% without affecting root growth. Thus, borrelidin might be a promising candidate for new antifungal agents against P. sojae.

[Biodiversity of mesophilic microbial community BYND-8 capability of lignocellulose degradation and its effect on biogas production].

The biodiversity of a mesophilic microbial community BYND-8 capable of degrading lignocellulose at 30 degrees C was detected using denaturing gradient gel electrophoresis (DGGE) and the isolation of pure cultures, and the effect of the liquid of rice straw degradation by BYND-8 on biogas production was measured. Six bacterial strains were isolated using peptone cellulose solution medium, and the highest similarities of their 16S rDNA gene sequences to Serratia sp. PSGB 13, S. marcescens strain UFLA-25LS, S. marcescens strain DAP33, Alcaligenes sp. YcX-20, Stenotrophomonas maltophilia strain C6, Bacillus cereus isolate BRL02-71 were 99%, 100%, 96%, 100%, 100% and 99%, respectively. In addition, one band was detected besides six bands of cultured isolates on the DGGE gel, and it showed 100% sequence similarity to uncultured bacterium clone ATB-KS-1446. The cumulative biogas and methane productions of biogas fermentation system added with the liquid of rice straw degraded by BYND-8 were 13 167 mL and 7 248 mL, 44.5% and 95.3% higher than those of the control, respectively, in the early 15 days of fermentation. The results showed that the biodiversity of microbial community BYND-8 was very high, and the time of producing biogas was put forward and biogas production was increased with application of microbial community for rice straw pretreatment during the biogas fermentation.