Chemical profile, antiproliferative and pro-apoptotic activities of essential oils of Pulicaria arabica against A549 lung cancer cell line

Pulicaria arabica has been traditionally utilized in folk medicine for various purposes such as ulcer treatments as well as antidiarrheal agent. Herein, the chemical profiles of Pulicaria arabica essential oils (PAEOs) and the in vitro antiproliferative effect of PAEOs were investigated. Hydrodistillation was employed to prepare PAEOs which were then characterized by GC/MS, while the antiproliferative effects were investigated by MTT assay as well as flow cytometric and RT-PCR analysis. Sixty-four (99.99 %) constituents were recognized from PAEOs. Carvotanacetone (36.97 %), (-)-carvomenthone (27.20 %) and benzene, 2-(1,1-dimethylethyl)-1,4-dimethoxy- (6.92 %) were the main components. PAEOs displayed IC50 values ranging from 30 to 50 μg/mL. DNA content analysis revealed that A549 cells exposed to PAEOs exhibited an increase in G1 cells population. The flow cytometry analysis results also showed that the PAEOs antiproliferative effect was mediated via apoptosis induction. Furthermore, a modulation in the pro-apoptotic markers (caspase-3 and Bax) and anti-apoptotic (Bcl-2) was also observed. In conclusion, PAEOs exhibited a moderate anti-proliferative effect on A549 cells through modulating the cell cycle progression and apoptosis initiation. These findings could offer a potential therapeutic use of PAEOs in lung cancer treatment.

Pulicaria jaubertii E. Gamal-Eldin reduces triacylglyceride content and modifies cellular antioxidant pathways in 3T3-L1 adipocytes

Levels of obesity in Middle Eastern countries are increasing. Phytochemicals have anti-obesogenic properties as evidenced by prevention of adipocyte differentiation and blocking triacylglyceride (TG) accumulation. In Yemen, Pulicaria jaubertii E. Gamal-Eldin (PJ) is a food additive and a traditional medicine. We tested the hypothesis that phytochemicals present in PJ inhibit adipocytic responses during differentiation of 3T3-L1 preadipocytes to adipocytes. Methanolic extracts of PJ did not block expression of fatty acid binding protein 4 (FABP4) a marker of differentiation but did inhibit TG accumulation. Treatment of 3T3-L1 preadipocytes increased NADPH:quinone oxidoreductase 1 (NQO1), a suppressor of TG accumulation. Further fractionation of the methanolic PJ extract with hexane and dichloromethane (DCM) demonstrated that bioactivity towards TG reduction and elevated expression of NQO1 and other antioxidant genes (glutamate cysteine ligase catalytic unit, glutathione disulfide reductase, glutathione peroxidase (GPx) 4 resided in the DCM fraction. Activity towards depleting GSH and elevating the expression of catalase and GPx3 were found in the DCM and hexane fractions. Analysis by gas chromatography and liquid chromatography coupled with mass spectrometry demonstrated the presence of catechin-like moieties in the DCM and methanolic fractions and suggest that these components were partially responsible for the bioactivity of these fractions. In summary, our data indicate that fractions derived PJ exhibit anti-adipogenic properties in part through the presence of catechin-like compounds.

Chemical composition and biological evaluation of essential oils of Pulicaria jaubertii

Background:

The present study reports and compares the results of Gas Chromatographic-Mass analyses of Pulicaria jaubertii leaf (P-1) and root (P-2) essential oils, as well as their in vitro antimicrobial and cytotoxic activities.

Materials and Methods:

The chemical composition of P-1 and P-2 essential oils of P. jaubertii, was investigated by GC-MS. Moreover, the essential oils were evaluated for their antimicrobial activity using the broth micro-dilution assay for minimum inhibitory concentrations (MIC). The crystal violet staining method (CVS) was used for evaluation of their cytotoxic activity on HEPG-2 and MCF-7 human cell lines.

Results:

This investigation led to the identification of 16 constituents in P-1, and 23 constituents in P-2, representing 99.92% and 94.74% of the oils respectively. Oxygenated monoterpenes were found to be the major group in both P-1 (99.47%) and P-2 (89.88%). P-1 consists almost entirely of p-Menth-6-en-2-one (Carvotanacetone, 98.59%). P-2 is characterized by high contents of each of Dimethoxydurene (38.48%), Durenol (26.89%) and 2’,4’-Dimethoxy-3’-methylacetophenone (20.52%). Both oils showed moderate antimicrobial activity against the Gram-positive strains and C. albicans. However, no activity was shown against Gram-negative bacteria. P-1 showed a significant cytotoxic activity against both MCF-7 and HEPG-2 (IC₅₀ = 3.8 and 5.1 μg/ml, respectively), while P-2 showed selective cytotoxic activity against MCF-7 cell line (IC₅₀ = 9.3 μg/ml).

Conclusion:

The potent cytotoxic and moderate antimicrobial activities of P-1 may be attributed to its high content of Carvotanacetone.