Inorganic Element Determination of Romanian Populus nigra L. Buds Extract and In Vitro Antiproliferative and Pro-Apoptotic Evaluation on A549 Human Lung Cancer Cell Line

Antioxidant Extracts from Greek and Spanish Olive Leaves: Antimicrobial, Anticancer and Antiangiogenic Effects

Olea europaea L. is the most valuable species of the Olea type, and its products offer a wide range of therapeutical uses. The olive tree has been extensively studied for its nourishing qualities, and the "Mediterranean diet", which includes virgin olive oil as a key dietary component, is strongly associated with a reduced risk of cardiovascular disease and various malignancies. Olive leaves, a by-product in the olive harvesting process, are valued as a resource for developing novel phytomedicines. For this purpose, two ethanolic extracts obtained from Olivae folium from Spain (OFS) and Greece (OFG) were investigated. Our findings contribute to a wider characterization of olive leaves. Both extracts displayed important amounts of phenolic compounds and pentacyclic triterpenes, OFG having higher concentrations of both polyphenols, such as oleuropein and lutein, as well as triterpenes, such as oleanolic acid and maslinic acid. The antioxidant capacity is similar for the two extracts, albeit slightly higher for OFG, possibly due to metal polyphenol complexes with antioxidant activity. The extracts elicited an antimicrobial effect at higher doses, especially against Gram-positive bacteria, such as Streptococcus pyogenes. The extract with lower inorganic content and higher content of polyphenols and triterpenic acids induced a strong anti-radical capacity, a selective cytotoxic effect, as well as antimigratory potential on A375 melanoma cells and antiangiogenic potential on the CAM. No irritability and a good tolerability were noted after evaluating the extracts on the in vivo Hen's Egg Test-Chorioallantoic Membrane (HET-CAM). Therefore, the present data are suggestive for the possible use of the two types of olive leaf products as high-antioxidant extracts, potentially impacting the healthcare system through their use as antimicrobial agents and as anticancer and anti-invasion treatments for melanoma.

Co-delivery of artemisinin and metformin via PEGylated niosomal nanoparticles: potential anti-cancer effect in treatment of lung cancer cells

PURPOSE

Despite the advances in treatment, lung cancer is a global concern and necessitates the development of new treatments. Biguanides like metformin (MET) and artemisinin (ART) have recently been discovered to have anti-cancer properties. As a consequence, in the current study, the anti-cancer effect of MET and ART co-encapsulated in niosomal nanoparticles on lung cancer cells was examined to establish an innovative therapy technique.

METHODS

Niosomal nanoparticles (Nio-NPs) were synthesized by thin-film hydration method, and their physicochemical properties were assessed by FTIR. The morphology of Nio-NPs was evaluated with FE-SEM and AFM. The MTT assay was applied to evaluate the cytotoxic effects of free MET, free ART, their encapsulated form with Nio-NPs, as well as their combination, on A549 cells. Apoptosis assay was utilized to detect the biological processes involved with programmed cell death. The arrest of cell cycle in response to drugs was assessed using a cell cycle assay. Following a 48-h drug treatment, the expression level of hTERT, Cyclin D1, BAX, BCL-2, Caspase 3, and 7 genes were assessed using the qRT-PCR method.

RESULTS

Both MET and ART reduced the survival rate of lung cancer cells in the dose-dependent manner. The IC50 values of pure ART and MET were 195.2 μM and 14.6 mM, respectively while in nano formulated form their IC50 values decreased to 56.7 μM and 78.3 μM, respectively. The combination of MET and ART synergistically decreased the proliferation of lung cancer cells, compared to the single treatments. Importantly, the combination of MET and ART had a higher anti-proliferative impact against A549 lung cancer cells, with lower IC50 values. According to the result of Real-time PCR, hTERT, Cyclin D1, BAX, BCL-2, Caspase 3, and Caspase 7 genes expression were considerably altered in treated with combination of nano formulated MET and ART compared to single therapies.

CONCLUSION

The results of this study showed that the combination of MET and ART encapsulated in Nio-NPs could be useful for the treatment of lung cancer and can increase the efficiency of lung cancer treatment.

Green Synthesis of Silver Nanoparticles Using Populi gemmae Extract: Preparation, Physicochemical Characterization, Antimicrobial Potential and In Vitro Antiproliferative Assessment

Green route is an economic, facile and eco-friendly method, employed for the synthesis of various types of nanoparticles, having it as a starting point biological entity, especially as a plant extract. The present study aims to obtain silver nanoparticles (AgNPs) starting from an ethanolic extract of Populi gemmae (Pg), by adjusting the reaction parameters. The morphological and structural characterization exhibited that both the reaction temperature and the concentration of metal salt, contributes to the obtaining of Pg-AgNPs with adjustable size and shape. The newly synthesized nanoparticles exhibited a good antibacterial activity on Gram-positive bacteria as well as antifungal activity. The in vitro antiproliferative activity of Pg-AgNPs was assessed on two different cancer cell lines (breast cancer cells-MCF7 and lung carcinoma epithelial cells-A549). Results have shown that the green-synthetized Pg-AgNPs_S2 (obtained at 60 °C, using AgNO3 of 5 M) induced a substantial decrease in tumor cell viability in a dose-dependent manner with an IC50 ranging from 5.03 to 5.07 µg/mL on A549 cell line and 3.24 to 4.93 µg/mL on MCF7 cell line.

Antimicrobial activity, in vitro anticancer effect (MCF-7 breast cancer cell line), antiangiogenic and immunomodulatory potentials of Populus nigra L. buds extract

PURPOSE

The aim of this study was to evaluate the antioxidant potential, antimicrobial activity, the in vitro anticancer effect (tested on MCF-7 breast cancer cell line), as well as the antiangiogenic and immunomodulatory potential of Populus nigra L. bud (Pg) extract collected from the western part of Romania.

RESULTS

Populus nigra L. bud extract presents an important antioxidant activity, due to the rich phytochemical composition. Regarding the biological activity, results have shown that poplar bud extract presents a significant inhibitory activity against Gram-positive bacteria and a dose-dependent decrease of MCF-7 tumor cell viability with an IC₅₀ of 66.26 μg/mL, while not affecting healthy cells. Phenomena of early apoptotic events at the maximum concentration tested (150 μg/mL) were detected by Annexin V-PI double staining. The extract induced G0/G1 phase cell cycle arrest. In addition, Pg extract showed antiangiogenic potential on the chorioallantoic membrane. Also, at the highest concentration (150 μg/mL), good tolerability and no signs of toxicity upon vascular plexus were observed. Moreover, in low concentrations, the Pg extract had immunomodulatory activity on primary human dendritic cells by upregulating IL-12 and IL-23 subunits.

CONCLUSION

The study concludes that poplar bud extract elicited antioxidant activity, antitumor properties on the breast cancer cell line, followed by an antiangiogenic effect and an immunomodulatory potential on human primary dendritic cells. The biological activity of Populus nigra L. buds extract may open new directions of research on the topic addressed.