Search

Psoriasis is considered as a common chronic immune-mediated skin disorder characterized by abnormal keratinocyte proliferation. Luteolin, an anti-inflammatory natural flavonoid with well-accepted inhibition effect against keratinocyte proliferation, was hypothesized to have a potential therapeutic effect for psoriasis. In this paper, we investigated the relieving effect of luteolin against imiquimod-induced psoriasis-like lesions on BALB/c mice and its possible anti-inflammatory mechanisms in lipopolysaccharide-stimulated macrophages (RAW264.7 cells). We found that luteolin ameliorated psoriasis-like skin lesions, suppressed the cutaneous infiltration of macrophages, T cells and neutrophils, and downregulated the expression of cytokines like IL-6, IL-1β, TNF-α, IL-17A and IL-23 in both skin lesions and eyeball blood of model mice. In vitro, we observed luteolin significantly suppressed the levels of psoriasis-related pro-inflammatory cytokines, such as IL-17A, IL-6, TNF-α and IL-23, and inflammatory mediators like nitric oxide NO, inducible NOS, COX-2 in RAW264.7 cells. The anti-inflammatory activity was accomplished by inhibiting NF-κB expression and activation. This study demonstrates luteolin is effective in alleviating psoriasis-like skin lesions and downregulating inflammatory response via NF-κB pathway, suggesting luteolin as a potential molecule for further therapeutic research of inflammation-related skin diseases like psoriasis.

At present, researches on various areas have been benefited from the advancement in solid-phase microextraction (SPME) technique, which covers a wide scope of analytes with different properties, facilitates on-site sampling and sample preparation, allows automated operation with high sample throughput, and facilitates long-range monitoring. As the scope of SPME grows, further increases in the specificity, speed and efficiency of this technique are still urgently needed. Application of auxiliary energies is one of the efficient strategies to achieve the aforementioned purpose. This review offers a brief discussion concerning several physical assistive technologies of SPME (e.g. vacuum, ultrasound, microwave, electrical driving force, magnetism, etc.) with respect to targeted or untargeted analysis of different substances in environmental, biological and food samples. Achievements, limitations, and future trends of these applications are also discussed. This review article is believed to be conductive to future applications of auxiliary energy assisted SPME methods in various fields.

Compounds extracted from essential oil of the Lavandula angustifolia by steam distillation were analysed by gas chromatography with quadrupole time-of-flight mass spectrometry (GC-QTOF/MS) and their anti-inflammatory activity were tested by a 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced inflammation method. The GC-QTOF/MS analysis identified 50 constituents, all representing 96.89% of the essential oil total composition. In particular, match factors, accurate mass and retention indexes were used to improve the accuracy of qualitative results. The main compounds identified were linalyl acetate (28.89%), linalool (24.30%), caryophyllene (7.89%), (E)-3,7-dimethylocta-1,3,6-triene (4.64%), 4-terpineol (4.04%), acetic acid lavandulyl ester (3.49%), borneol (2.60%) and eucalyptol (2.05%). Regarding anti-inflammatory activity, the essential oil was effective against the TPA-induced inflammation in mouse ear. The inhibition effect of essential oils (100 mg/kg) on TPA-induced mouse ear edema was about 58.66%. Meanwhile, the expression levels of transcription factor, nuclear factor kappa-B (NF-κB), inflammatory cytokine, cyclooxygenase-2 (COX-2) and tumor necrosis factor (TNF-α) were also decreased significantly. The results in this study show essential oil had a better anti-inflammatory activity than that of ibuprofen at the same dosage, which demonstrated a great potential value in application.

Glycosidically bound aroma compounds in three different types of tobacco were investigated. After isolation of extracts obtained by Amberlite XAD-2 adsorption and ethyl acetate elution, glycosides were analyzed after enzymatic hydrolysis by gas chromatography-mass spectrometry (GC-MS) or directly after trifluoroacetylated (TFA) derivatization by GC-MS in electron ionization (EI) and negative chemical ionization (NCI) mode. In total 21 bound aglycones were identified by β-glucosidase hydrolysis. These aglycones mainly consisted of C13-norisoprenoids, aromatic components and sesquiterpenoids. Additionally, with the aid of enzymatic hydrolysis, 15 β-d-glucopyranosides and 1 β-d-rutinoside were tentatively identified by TFA derivatization. TFA method was validated by repeatability and successfully employed to analyze different types of tobacco. Principal component analysis (PCA) was carried out on identified glycoside variables to visualize the difference between the tobacco types and the relationship between the glycoside variables and the tobacco types was established.