Lavandula angustifolia Mill. Essential Oil Exerts Antibacterial and Anti-Inflammatory Effect in Macrophage Mediated Immune Response to Staphylococcus aureus.

Different studies described the antibacterial properties of Lavandula angustifolia (Mill.) essential oil and its anti-inflammatory effects. Besides, no data exist on its ability to activate human macrophages during the innate response against Staphylococcus aureus. The discovery of promising regulators of macrophage-mediated inflammatory response, without side effects, could be useful for the prevention of, or as therapeutic remedy for, various inflammation-mediated diseases. This study investigated, by transcriptional analysis, how a L. angustifolia essential oil treatment influences the macrophage response to Staphylococcus aureus infection. The results showed that the treatment increases the phagocytic rate and stimulates the containment of intracellular bacterial replication by macrophages. Our data showed that this stimulation is coupled with expression of genes involved in reactive oxygen species production (i.e., CYBB and NCF4). Moreover, the essential oil treatment balanced the inflammatory signaling induced by S. aureus by repressing the principal pro-inflammatory cytokines and their receptors and inducing the heme oxygenase-1 gene transcription. These data showed that the L. angustifolia essential oil can stimulate the human innate macrophage response to a bacterium which is responsible for one of the most important nosocomial infection and might suggest the potential development of this plant extract as an anti-inflammatory and immune regulatory coadjutant drug.

Stress responses of duckweed (Lemna minor L.) and water velvet (Azolla filiculoides Lam.) to anionic surfactant sodium-dodecyl-sulphate (SDS).

Surfactants are used for several purposes and recently they have attracted the attention for their ability to modify the behavior of other preexistent or co-disposed contaminants, although their use or discharge in wastewaters can represent a real or potential risk for the environment. Lemna minor L. and Azolla filiculoides Lam. are floating aquatic macrophytes, very effective in accumulating several pollutants including sodium dodecyl sulphate (SDS). In this work we evaluated the effects of SDS on these species by determining the stress ethylene production via laser-based trace gas detection, and the activities of enzymes involved in stress response, such as guaiacol peroxidase (G-POD), phenylalanine ammonia-lyase (PAL) and polyphenol-oxidase (PPO). Phenolics content was also determined. The macrophytes were treated with different concentrations of SDS for one week. SDS affected duckweed enzymatic activities and phenol content. While in the fern phenolics amount, PAL, G-POD and PPO activities were not affected by SDS except for 100 ppm SDS, the only concentration that was taken up and not completely degraded. Stress ethylene production was induced only in the fern treated with 50 and 100 ppm SDS.

Role of transglutaminase 2 in quercetin-induced differentiation of B16-F10 murine melanoma cells.

Flavonoids belong to the class of plant polyphenolic compounds with over 6,000 individual structures known. These phytochemicals have attracted the interest of the scientists, because they possess a remarkable spectrum of biological activities, such as antiallergic, antiinflammatory, antioxidant, antimutagenic and anticarcinogenic. In this work, we compared the anticancer potential of two flavonoids, quercetin and pelargonidin, on highly metastatic B16-F10 melanoma murine cells. We have evaluated different parameters related to cell proliferation and differentiation, such as cell number, toxicity, intracellular content of polyamines and transglutaminase (TG, EC 2.3.2.13) activity. The higher inhibition of tumor cell growth, with respect to control, was obtained with quercetin cell treatment, i.e. 32% reduction after 48 h and 39% reduction after 72 h of incubation (P < 0.001). In parallel, quercetin-treated cells showed a similar decrease in polyamine content. TG activity was fourfold increased, with respect to control, after 48 h and twofold increased after 72 h (P < 0.001). Pelargonidin treatment did not show significant antiproliferative effects and any increase in TG activity. Proteomic approach was used to investigate changes in protein expression profiles in tumor cells following quercetin treatment. Changes in expression of 60 proteins were detected, i.e. 8 proteins were down-regulated, 35 up-regulated, 11 "de novo" synthetized proteins and 6 suppressed proteins were present in treated cells. A 80 kDa spot, identified as TG type 2 by Western blot analysis, presented a fourfold increase in intensity, confirming the key role played by TG in the induction of cancer cell differentiation.