Trifluoromethylcinnamanilide Michael Acceptors for Treatment of Resistant Bacterial Infections.

A series of thirty-two anilides of 3-(trifluoromethyl)cinnamic acid (series 1) and 4-(trifluoromethyl)cinnamic acid (series 2) was prepared by microwave-assisted synthesis. All the compounds were tested against reference strains Staphylococcus aureus ATCC 29213 and Enterococcus faecalis ATCC 29212 and resistant clinical isolates of methicillin-resistant S. aureus (MRSA) and vancomycin-resistant E. faecalis (VRE). All the compounds were evaluated in vitro against Mycobacterium smegmatis ATCC 700084 and M. marinum CAMP 5644. (2E)-3-[3-(Trifluoromethyl)phenyl]-N-[4-(trifluoromethyl)phenyl]prop-2-enamide (1j), (2E)-N-(3,5-dichlorophenyl)-3-[3-(trifluoromethyl)phenyl]prop-2-enamide (1o) and (2E)-N-[3-(trifluoromethyl)phenyl]-3-[4-(trifluoromethyl)-phenyl]prop-2-enamide (2i), (2E)-N-[3,5-bis(trifluoromethyl)phenyl]-3-[4-(trifluoromethyl)phenyl]-prop-2-enamide (2p) showed antistaphylococcal (MICs/MBCs 0.15-5.57 µM) as well as anti-enterococcal (MICs/MBCs 2.34-44.5 µM) activity. The growth of M. marinum was strongly inhibited by compounds 1j and 2p in a MIC range from 0.29 to 2.34 µM, while all the agents of series 1 showed activity against M. smegnatis (MICs ranged from 9.36 to 51.7 µM). The performed docking study demonstrated the ability of the compounds to bind to the active site of the mycobacterial enzyme InhA. The compounds had a significant effect on the inhibition of bacterial respiration, as demonstrated by the MTT assay. The compounds showed not only bacteriostatic activity but also bactericidal activity. Preliminary in vitro cytotoxicity screening was assessed using the human monocytic leukemia cell line THP-1 and, except for compound 2p, all effective agents did show insignificant cytotoxic effect. Compound 2p is an interesting anti-invasive agent with dual (cytotoxic and antibacterial) activity, while compounds 1j and 1o are the most interesting purely antibacterial compounds within the prepared molecules.

Prenylated Stilbenoids Affect Inflammation by Inhibiting the NF-κB/AP-1 Signaling Pathway and Cyclooxygenases and Lipoxygenase.

Stilbenoids are important components of foods (e.g., peanuts, grapes, various edible berries), beverages (wine, white tea), and medicinal plants. Many publications have described the anti-inflammatory potential of stilbenoids, including the widely known trans-resveratrol and its analogues. However, comparatively little information is available regarding the activity of their prenylated derivatives. One new prenylated stilbenoid (2) was isolated from Artocarpus altilis and characterized structurally based on 1D and 2D NMR analysis and HRMS. Three other prenylated stilbenoids were prepared synthetically (9-11). Their antiphlogistic potential was determined by testing them together with known natural prenylated stilbenoids from Macaranga siamensis and Artocarpus heterophyllus in both cell-free and cell assays. The inhibition of 5-lipoxygenase (5-LOX) was also shown by simulated molecular docking for the most active stilbenoids in order to elucidate the mode of interaction between these compounds and the enzyme. Their effects on the pro-inflammatory nuclear factor-κB (NF-κB) and the activator protein 1 (AP-1) signaling pathway were also analyzed. The THP1-XBlue-MD2-CD14 cell line was used as a model for determining their anti-inflammatory potential, and lipopolysaccharide (LPS) stimulation of Toll-like receptor 4 induced a signaling cascade leading to the activation of NF-κB/AP-1. The ability of prenylated stilbenoids to attenuate the production of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) was further evaluated using LPS-stimulated THP-1 macrophages.

We Are What We Eat: A Stoichiometric and Ecometabolomic Study of Caterpillars Feeding on Two Pine Subspecies of Pinus sylvestris.

Many studies have addressed several plant-insect interaction topics at nutritional, molecular, physiological, and evolutionary levels. However, it is still unknown how flexible the metabolism and the nutritional content of specialist insect herbivores feeding on different closely related plants can be. We performed elemental, stoichiometric, and metabolomics analyses on leaves of two coexisting Pinus sylvestris subspecies and on their main insect herbivore; the caterpillar of the processionary moth (Thaumetopoea pityocampa). Caterpillars feeding on different pine subspecies had distinct overall metabolome structure, accounting for over 10% of the total variability. Although plants and insects have very divergent metabolomes, caterpillars showed certain resemblance to their plant-host metabolome. In addition, few plant-related secondary metabolites were found accumulated in caterpillar tissues which could potentially be used for self-defense. Caterpillars feeding on N and P richer needles had lower N and P tissue concentration and higher C:N and C:P ratios, suggesting that nutrient transfer is not necessarily linear through trophic levels and other plant-metabolic factors could be interfering. This exploratory study showed that little chemical differences between plant food sources can impact the overall metabolome of specialist insect herbivores. Significant nutritional shifts in herbivore tissues could lead to larger changes of the trophic web structure.

Ring-substituted 8-hydroxyquinoline-2-carboxanilides as potential antimycobacterial agents.

In this study, a series of twenty-two ring-substituted 8-hydroxyquinoline-2-carboxanilides was prepared and characterized. Primary in vitro screening of the synthesized compounds was performed against Mycobacterium tuberculosis H37Ra, Mycobacterium avium complex and M. avium subsp. paratuberculosis. Some of the tested compounds showed the antimycobacterial activity against M. avium subsp. paratuberculosis comparable with or higher than that of rifampicin. 8-Hydroxy-N-[3-(trifluoromethyl)phenyl]- and 8-hydroxy-N-[4-(trifluoromethyl)phenyl]quinoline-2-carboxamide showed MIC=24 µM against all tested mycobacterial strains. 3-Methoxyphenyl- and 3-methylphenyl derivatives expressed MIC=27 or 29 µM also against all the tested strains. Their activity against M. avium subsp. paratuberculosis was 4-fold higher than that of rifampicin. 2-Bromophenyl- and 2-(trifluoromethyl)phenyl derivatives had MIC=23 or 24 µM against M. tuberculosis. A significant decrease of mycobacterial cell metabolism (viability of M. tuberculosis H37Ra) was observed using MTT assay. Screening of cytotoxicity of the compounds was performed using the THP-1 cells, and no significant lethal effect was observed up to tested concentration 30 µM. The structure-activity relationships are discussed.

Warming differentially influences the effects of drought on stoichiometry and metabolomics in shoots and roots.

Plants in natural environments are increasingly being subjected to a combination of abiotic stresses, such as drought and warming, in many regions. The effects of each stress and the combination of stresses on the functioning of shoots and roots have been studied extensively, but little is known about the simultaneous metabolome responses of the different organs of the plant to different stresses acting at once. We studied the shift in metabolism and elemental composition of shoots and roots of two perennial grasses, Holcus lanatus and Alopecurus pratensis, in response to simultaneous drought and warming. These species responded differently to individual and simultaneous stresses. These responses were even opposite in roots and shoots. In plants exposed to simultaneous drought and warming, terpenes, catechin and indole acetic acid accumulated in shoots, whereas amino acids, quinic acid, nitrogenous bases, the osmoprotectants choline and glycine betaine, and elements involved in growth (nitrogen, phosphorus and potassium) accumulated in roots. Under drought, warming further increased the allocation of primary metabolic activity to roots and changed the composition of secondary metabolites in shoots. These results highlight the plasticity of plant metabolomes and stoichiometry, and the different complementary responses of shoots and roots to complex environmental conditions.