Volatile Oils of Nepeta tenuifolia (Jing Jie) as an Alternative Medicine against Multidrug-Resistant Pathogenic Microbes.

Essential oils from the dried spikes of Nepeta tenuifolia (Benth) are obtained by steam distillation. Pulegone was identified as the main component in the spikes of N. tenuifolia through analysis, with greater than 85% purity obtained in this study. The essential oils are extremely active against all Gram-positive and some Gram-negative reference bacteria, particularly Salmonella enterica, Citrobacter freundii, and Escherichia coli. The minimum inhibitory concentration was found to be between 0.08 and 0.78% (against S. enterica), 0.39 and 0.78% (against C. freundii), and 0.097 and 0.39% (against E. coli), whereas the minimum bactericidal concentration varied in range from 0.097% to 1.04%. In general, the essential oils show a strong inhibitory action against all tested reference strains and clinical isolates. However, the antibacterial activity of EOs against both Pseudomonas aeruginosa reference strains and clinical isolates was relatively lower than other Gram-negative pathogens. The essential oils of N. tenuifolia also displayed bactericidal activities (MBC/MIC < 4) in this study. These findings reflect the bactericidal activity of the essential oils against a wide range of multidrug-resistant clinical pathogens in an in vitro study. In addition, we propose the fragmentation pathways of pulegone and its derivatives by LC-ESI-MS/MS in this study.

Low-cell-number, single-tube amplification (STA) of total RNA revealed transcriptome changes from pluripotency to endothelium.

BACKGROUND: In addition to messenger RNA (mRNA), noncoding RNAs (ncRNAs) are essential components in cellular machineries for translation and splicing. Besides their housekeeping functions, ncRNAs are involved in cell type-specific regulation of translation, mRNA stability, genome structure, and accessibility. To have a comprehensive understanding of the identities and functions of different cell types, a method to comprehensively quantify both mRNA and ncRNA in a sensitive manner is highly desirable. METHODS: Here we tried to develop a system capable of concurrently profiling both mRNA and ncRNA by polyadenylating RNA in samples before reverse transcription. The sensitivity of the system was maximized by avoiding purification from cell lysis to amplified cDNA and by optimizing the buffer conditions. The single-tube amplification (STA) system was applied to single to 100 cells of 293T cells, human pluripotent stem cells (hPSCs) and their differentiated endothelial progenies to validate its quantitative power and sensitivity by qPCR and high-throughput sequencing. RESULTS: Using microRNA (miRNA) as an example, we showed that complementary DNA (cDNA) from ncRNAs could be amplified and specifically detected from a few cells within a single tube. The sensitivity of the system was maximized by avoiding purification from cell lysis to amplified cDNA and by optimizing the buffer conditions. With 100 human embryonic stem cells (hESCs) and their differentiated endothelial cells as input for high-throughput sequencing, the single-tube amplification (STA) system revealed both well-known and other miRNAs selectively enriched in each cell type. The selective enrichment of the miRNAs was further verified by qPCR with 293FT cells and a human induced pluripotent stem cell (hiPSC) line. In addition, the detection of other non-miRNA transcripts indicated that the STA target was not limited to miRNA, but extended to other ncRNAs and mRNAs as well. Finally, the STA system was capable of detecting miRNA and mRNA expression down to single cells, albeit with some loss of sensitivity and power. CONCLUSIONS: Overall, STA offered a simple and sensitive way to concurrently quantify both mRNA and ncRNA expression in low-cell-number samples for both qPCR and high-throughput sequencing.

Analgesic and anti-inflammatory activities of Torenia concolor Lindley var. formosana Yamazaki and betulin in mice.

The present study was intended to examine the analgesic effect of the 70% methanol extract of Torenia concolor Lindley var. formosana Yamazaki (TC(MeOH)) and betulin using models of acetic acid-induced writhing response and formalin test. In addition, we investigated the anti-inflammatory effect of TC(MeOH) and betulin using model of lambda-carrageenan-induced paw edema. We observed the activities of antioxidant enzymes (SOD, GPx and GR) in the liver and the levels of malondialdehyde (MDA) and nitric oxide (NO) in the edema paw. The results showed that TC(MeOH) (1.0 and 2.0 g/kg) and betulin (30 and 90 mg/kg), significantly inhibited the acetic acid-induced writhing response. TC(MeOH) (2.0 g/kg) and betulin (30 and 90 mg/kg) significantly inhibited formalin-induced licking time during both the early and late phases. TC(MeOH) (0.5, 1.0 and 2.0 g/kg) and betulin (30 and 90 mg/kg) also significantly decreased the paw edema at the 4th hour after lambda-carrageenan injection. Furthermore, TC(MeOH) and betulin treatment also significantly increased the activities of SOD, GR and GPx in the liver while decreasing the level of MDA in the edema paw. Finally, betulin (30 and 90 mg/kg) also caused considerable reduction of NO level in the edema paw. Taken together, the present results indicated that TC(MeOH) and betulin possessed analgesic and anti-inflammatory effects. The anti-inflammatory mechanism of TC(MeOH) and betulin may be related to decreasing the levels of MDA and NO in the edema paw by increasing the activities of antioxidant enzymes in the liver.

Differential effects of natural polyphenols on neuronal survival in primary cultured central neurons against glutamate- and glucose deprivation-induced neuronal death.

Neuronal injury in the central nervous system following ischemic insult is believed to result from glutamate toxicity and glucose deprivation. In this study, polyphenols isolated from Scutellaria baicalensis Georgi, including baicalin, baicalein, and wogonin, were investigated for their neuroprotective effects against glutamate/NMDA (Glu/NMDA) stimulation and glucose deprivation in primary cultured rat brain neurons. Cell death was accessed by lactate dehydrogenase (LDH) release assay for necrosis, and mitochondrial activity was accessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) reduction activity assay. It was found that both baicalin and baicalein decreased LDH release of the cultured neurons after 24 h treatment, whereas wogonin profoundly increased LDH release after 2 h treatment and resulted in neuronal death after 24 h. Glu/NMDA treatment profoundly increased LDH release and moderately decreased MTT reduction activity in an NMDA receptor-dependent manner. Both baicalin and baicalein significantly reduced Glu/NMDA-increased LDH release, in which baicalein is much more potent than baicalin. Glu/NMDA-increased intracellular calcium was also significantly attenuated by baicalin and baicalein. Baicalin and baicalein did not affect glutamate receptor binding activity, but baicalein did moderately decrease Glu/NMDA-induced nitric oxide (NO) production. In the glucose deprivation (GD) study, baicalein but not baicalin showed significant protective effects on the GD-increased LDH release, without affecting the GD-induced NO production, in cultured rat brain neurons. These results suggest that baicalein is the most effective compound among three polyphenols tested in preventing neurotoxicity induced by both glutamate and GD, whereas baicalin was only effective in preventing glutamate toxicity. Wogonin might have a neurotoxic effect on the brain.