Prunella vulgaris L.: An Updated Overview of Botany, Chemical Composition, Extraction Methods, and Biological Activities.

Prunella vulgaris L. (PV) is a well-known renewable drug resource full of different groups of biologically active substances with a wide range of pharmacological actions and applications in medicine. In this review, we present an updated comprehensive overview of the botany, extracting methods, chemical composition, and pharmacological activity of different parts of PV extracts. As a result of this review, it was found that chemical composition of PV depends on various factors ranging from the part of the plant to the method of extraction. We also highlight extraction methods that have not been previously used for obtaining PV extracts and may have high scientific interest. With this review, we hope to guide present and future professionals and provide possible previously unexplored areas to find new solutions associated with PV plant.

Formulation of an Origanum vulgare based dental gel with antimicrobial activity.

OBJECTIVES: This study aims to formulate a new Origanum vulgare anti-caries dental gel with high antimicrobial activity. METHODS: O. vulgare essential oil was extracted using hydro-distillation, ethanol extraction, gas chromatography/mass spectrometry, and high-performance liquid chromatography methods. Antimicrobial activity of the produced gels with oregano oil and extract was determined through the disco-diffusion method. The effectiveness of O. vulgare essential oil was tested in vitro for Streptococcus mutans biofilm using colorimetric analysis. RESULTS: O. vulgare essential oil inhibited the growth of S. mutans biofilm by 98% compared with unexposed control bacteria (p <0.05). Five samples of anti-caries gel (ACDG1, ACDG2, ACDG3, ACDG4, ACDG5) were formulated using the obtained oregano essential oil and extract. Based on the microbiological study results, the ACDG1 and ACDG3 gel samples exhibited high antimicrobial activity against the gram-positive bacterial strains of Staphylococcus aureus and Bacillus subtilis and the yeast fungus Candida albicans and moderate antimicrobial activity against the gram-negative strains of Escherichia coli and Pseudomonas aeruginosa. CONCLUSION: Based on the results of this study, the ACDG3 sample may be considered an anti-caries gel owing to its high antimicrobial activity. This sample has good organoleptic properties compared to other samples, produces relatively high antimicrobial activity, and guards against cariogenic biofilms of S. mutans.

Inhibition of T Cell Receptor Activation by Semi-Synthetic Sesquiterpene Lactone Derivatives and Molecular Modeling of Their Interaction with Glutathione and Tyrosine Kinase ZAP-70.

A variety of natural compounds have been shown to modulate T cell receptor (TCR) activation, including natural sesquiterpene lactones (SLs). In the present studies, we evaluated the biological activity of 11 novel semi-synthetic SLs to determine their ability to modulate TCR activation. Of these compounds, α -epoxyarglabin, cytisinyl epoxyarglabin, 1 ß ,10 α -epoxyargolide, and chloroacetate grosheimin inhibited anti-CD3-induced Ca2+ mobilization and extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation in Jurkat T cells. We also found that the active SLs depleted intracellular glutathione (GSH) in Jurkat T cells, supporting their reactivity towards thiol groups. Because the zeta-chain associated tyrosine kinase 70 kDa (ZAP-70) is essential for TCR signaling and contains a tandem SH2 region that is highly enriched with multiple cysteines, we performed molecular docking of natural SLs and their semi-synthetic derivatives into the ZAP-70 binding site. The docking showed that the distance between the carbon atom of the exocyclic methylene group and the sulfur atom in Cys39 of the ZAP-70 tandem SH2 module was 3.04⁻5.3 Å for active compounds. Furthermore, the natural SLs and their derivatives could be differentiated by their ability to react with the Cys39 SH-group. We suggest that natural and/or semi-synthetic SLs with an α -methylene- γ -lactone moiety can specifically target GSH and the kinase site of ZAP-70 and inhibit the initial phases of TCR activation.

The natural sesquiterpene lactones arglabin, grosheimin, agracin, parthenolide, and estafiatin inhibit T cell receptor (TCR) activation.

Inhibition of the T cell receptor (TCR) pathway represents an effective strategy for the treatment of T cell-mediated inflammatory and autoimmune diseases. To identify natural compounds that could inhibit inflammatory T cell responses, we screened 13 sesquiterpene lactones, including achillin, arglabin, argolide, argracin, 3ß-hydroxyarhalin, artesin, artemisinin, estafiatin, grosheimin, grossmisin, leucomisine, parthenolide, and taurine, for their ability to modulate activation-induced Ca2+ mobilization in Jurkat T cells. Five of the compounds (arglabin, grosheimin, argracin, parthenolide, and estafiatin) inhibited anti-CD3-induced mobilization of intercellular Ca2+ ([Ca2⁺]i) in Jurkat cells, with the most potent being parthenolide and argacin (IC50 = 5.6 and 6.1 µM, respectively). Likewise, phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 in activated Jurkat cells was inhibited by these five compounds, with the most potent being parthenolide and estafiatin (IC50 = 13.8 and 15.4 µM, respectively). These compounds also inhibited ERK1/2 phosphorylation in primary human T cells and depleted intracellular glutathione. In contrast, none of the sesquiterpene lactones inhibited ERK1/2 phosphorylation in HL60 cells transfected with N-formyl peptide receptor 2 (FPR2) and stimulated with the FPR2 peptide agonist WKYMVM, indicating specificity for T cell activation. Estafiatin, a representative sesquiterpene lactone, was also profiled in a cell-based phosphokinase array for 43 kinase phosphorylation sites, as well as in a cell-free competition binding assay for its ability to compete with an active-site directed ligand for 95 different protein kinases. Besides inhibition of ERK1/2 phosphorylation, estafiatin also inhibited phosphorylation of p53, AMPKα1, CREB, and p27 elicited by TCR activation in Jurkat cells, but it did not bind to any of 95 kinases evaluated. These results suggest that arglabin, grosheimin, agracin, parthenolide, and estafiatin can selectively inhibit initial phases of TCR activation and may be natural compounds with previously undescribed immunotherapeutic properties.

(1S*,3R*,5S*,7S*)-4,4,8,8-Tetra-chloro-1-isopropyl-5-methyl-tri-cyclo-[5.1.0.0(3,5)]octa-ne.

The title compound, C12H16Cl4, is a derivative of the natural product 1-isopropyl-4-methyl-cyclo-hexa-1,4-diene, and represents a diastereomer with two trans-fused cyclo-propane rings. Both enanti-omers are present in the non-centrosymmetric polar space group Pna21. The central cyclo-hexane ring is planar within 0.02 (1) Å. The C atoms of di-chloro-methyl-ene groups deviate from this plane by 1.19 (1) and -1.26 (1) Å, whereas the isopropyl and methyl groups are oriented more equatorially, deviating by 0.71 (1) and -0.87 (1) Å, respectively.