Alnustone inhibits Streptococcus pneumoniae virulence by targeting pneumolysin and sortase A.

Streptococcus pneumoniae (S. pneumoniae) is a major Gram-positive opportunistic pathogen that causes pneumonia, bacteremia, and other fatal infections. This bacterium is responsible for more deaths than any other single pathogen in the world. Inexplicably, these symptoms persist despite the administration of effective antibiotics. Targeting pneumolysin (PLY) and sortase A (SrtA), the major virulence factors of S. pneumoniae, this study uncovered a novel resistance mechanism to S. pneumoniae infection. Using protein phenotype assays, we determined that the small molecule inhibitor alnustone is a potent drug that inhibits both PLY and SrtA. As essential virulence factors of S. pneumoniae, PLY and SrtA play a significant role in the occurrence of infection. Furthermore, evaluation using PLY-mediated hemolysis assay demonstrated alunstone had the potential to interrupt the haemolytic activity of PLY with treatment alunstone (4 µg/ml). Co-incubation of S. pneumoniae D39 SrtA with small-molecule inhibitors decreases cell wall-bound Nan A (pneumococcal-anchored surface protein SrtA), inhibits biofilm formation, and reduces biomass significantly. The protective effect of invasive pneumococcal disease (IPD) on murine S. pneumoniae was demonstrated further. Our study proposes a comprehensive bacteriostatic mechanism for S. pneumoniae and highlights the significant translational potential of targeting both PLY and SrtA to prevent pneumococcal infections. Our findings indicate that the antibacterial strategy of directly targeting PLY and SrtA with alnustone is a promising treatment option for S. pneumoniae and that alnustone is a potent inhibitor of PLY and SrtA.

Effect of Mongolian warm acupuncture on the gene expression profile of rats with insomnia.

BACKGROUND: The mechanism of Mongolian warm acupuncture (MWA) for the treatment of insomnia has not been previously reported. OBJECTIVE: To investigate the effect of MWA on gene expression profile in the p-chlorophenylalanine (PCPA)-induced rat model of insomnia. METHODS: A rat model of insomnia was established and the animals were divided into five groups: control, PCPA (untreated), PCPA+estazolam, PCPA+MA (manual acupuncture), and PCPA+MWA. The rats were euthanased at 7 days after treatment, and hypothalamic tissue was harvested to extract total RNA for the analysis of gene expression profile. Micro-array and Partek Genomics Suite analysis system were used to analyse differential expression of genes between groups. Furthermore, ingenuity pathways analysis was used to analyse the main regulators. RESULTS: After treatment, in rats with improved sleep, micro-array data from the follow-up phase compared with baseline showed that MWA down-regulated 11 genes compared with the control group and 16 genes compared with the PCPA group. Six genes were selected following the micro-array detection to perform quantitative polymerase chain reaction (qPCR) verification, and the results showed that the coincidence rate was up to 90%, which verified the reliability of the microarray results. Compared with the PCPA group, transcription levels of Egr 1, Btg2 and BDNF in the PCPA+MWA group were up-regulated (P<0.05). CONCLUSION: In combination, the findings of this study suggests that MWA is efficacious at improving sleep in an experimental rat model of insomnia.