MicroRNAs (miRNAs), which were initially discovered inCaenorhabditis elegans, can regulate gene expression by recognizing cognate sequences and interfering with the transcriptional or translational machinery. The application of bioinformatics tools for structural analysis and target prediction has largely driven the investigation of certain miRNAs. Notably, it has been found that certain miRNAs which are widely involved in the inflammatory response and immune regulation are closely associated with the occurrence, development, and outcome of bacterial pneumonia. It has been shown that certain miRNA techniques can be used to identify related targets and explore associated signal transduction pathways. This enhances the understanding of bacterial pneumonia, notably for “refractory” or drug-resistant bacterial pneumonia. Although these miRNA-based methods may provide a basis for the clinical diagnosis and treatment of this disease, they still face various challenges, such as low sensitivity, poor specificity, low silencing efficiency, off-target effects, and toxic reactions. The opportunities and challenges of these methods have been completely reviewed, notably in bacterial pneumonia. With the continuous improvement of the current technology, the miRNA-based methods may surmount the aforementioned limitations, providing promising support for the clinical diagnosis and treatment of “refractory” or drug-resistant bacterial pneumonia.

Zhou Y, et al. Immune Netw. 2022 Jun;22(3):e21. https://doi.org/10.4110/in.2022.22.e21

Objective: Antibiotic resistance of Pseudomonas aeruginosa (PA) that lowers the effectiveness of current treatments for pneumonia is a growing problem. Qi Gui Yin is a Chinese herbal medicine that has been used to improve the efficacy of antibiotic therapy against antibiotic-resistant bacteria. This study aimed to elucidate the mechanism by which Qi Gui Yin inhibits antibiotic resistance of PA. Methods: Active components of Qi Gui Yin were analyzed by chromatography. Isobaric Tags for Relative and Absolute Quantification (iTRAQ) technology was used to compare protein expression profiles of PA strains cultured in serum from rats that were and were not treated with Qi Gui Yin. Quantitative polymerase chain reaction (qPCR) analysis was performed to detect gene expression changes. Results: Proteomic analysis identified 76 differentially expressed proteins between PA strains cultured in serum from rats that were or were not treated with Qi Gui Yin. Bioinformatics analysis revealed that the largest number of differentially expressed proteins were associated with resistance mechanisms such as quorum sensing, bacterial biofilm formation, and active pumping. In addition, qPCR analysis confirmed that downregulation of iscU and arcA gene expression was associated with Qi Gui Yin treatment. Conclusions: Serum from Qi Gui Yin-treated rats could effectively inhibit antibiotic resistance of PA. Chlorogenic acid and astragaloside IV are the main components of Qi Gui Yin, which may mediate inhibition of antibiotic resistance. Our findings provide new insights into strategies involving Chinese herbal medicine that can be used to treat pneumonia caused by antibiotic-resistant bacteria.