Combination of nanosomal form of doxorubicin, interferon alpha, and nitroglycerin in the threatment of 101.8 glioblastoma in Wistar rats

The search for effective approaches to the treatment of patients with glioblastoma is one of the difficult tasks of neurooncology; standard methods of therapy show limited results. Combined therapy, which includes different antitumor mechanisms, can increase its effectiveness. The combination of PLGA nanoform of doxorubicin (Dox-PLGA), antitumor cytokine — interferon alfa (IFN-α), and nitrogen oxide (NO) donor nitroglycerin (NG) was investigated in this work both in vitro (rat C6 glioma) and in vivo (rat 101.8 glioblastoma). MTT assay in the C6 cell line showed great cytotoxicity and antiproliferative effect of the combination of IFN-α with Dox-PLGA and NG. The lowest tumour cell survival was observed when using a high dose of IFN-α (10 ng/ml) in mono-mode. In the in vivo experiment, 32 female Wistar rats with 101.8 glioblastoma received therapy in the following modes: Dox-PLGA + NG; Dox-PLGA + IFN-α; Dox- PLGA + IFN-α + NG. There was a significant increase in median survival and life expectancy (ILE) in all groups receiving therapy compared to the group that did not undergo treatment. The longest median lifespan (27 days), survival up to 100 days (1 animal), ILE (131%) were observed in animals that received the combination Dox-PLGA + IFN-α+ NG, compared to the group without treatment, in which the median lifespan was 15 days. Thus, the therapy of experimental glioblastoma both in vivo and in vitro with the combination of Dox-PLGA + IFN-α + NG has the most pronounced therapeutic and antitumor effect, which must be taken into account when developing new more effective methods of treating human glioblastomas.

Synthesis and Biological Evaluation of Novel 2-imino-4-thiazolidinones as Potential Antitumor Agents for Glioblastoma

Aims: The purpose of our study was to explore the molecular hybridization between 2-imino-4-thizolidione and piridinic scaffolds and its potential antitumor activity. Background: Glioblastoma is the most aggressive glioma tumor clinically diagnosed malignant and highly recurrent primary brain tumor type. The standard of treatment for a glioblastoma is surgery, followed by radiation and chemotherapy using temozolomide. However, the chemoresistance has become the main barrier to treatment success. 2-imino-4-thiazolidinones are an important class of heterocyclic compounds that feature anticancer activity; however the antiglioblastoma activity is yet to be explored. Objective: To synthesize and characterize a series of novel 2-imino-4-thiazolidinones and evaluate their antiglioblastoma activity. Method: The 2-imino-4-thiazolidinone (5a-p) was synthesized according to the literature with modifications. Compounds were identified and characterized using spectroscopic analysis and X-ray diffraction. The antitumor activity was analyzed by 3-(4,5- dimethyl)-2,5-diphenyltetrazolium bromide (MTT) assay both in primary astrocyte and glioma (C6). Apoptosis and cell cycle phase were determined by flow cytometry analysis. The expression of caspase-3/7 was measured by luminescence assay. Oxidative stress parameters as: determination of reactive oxygen species (ROS), superoxide dismutase (SOD) activity, catalase (CAT) activity and total sulfhydryl content quantification were analyzed by colorimetric assays according to literature. Results: Among sixteen synthesized compounds, three displayed potent antitumor activities against tested glioblastoma cell line showed IC50 values well below the standard drug temozolomide. Therefore, compounds 5a, 5l and 5p were evaluated using cell cycle and death analysis, due to potent toxicity (2.17±1.17, 6.24±0.59, 2.93±1.12µM, respectively) in C6 cell line. The mechanism of action studies demonstrated that 5a and 5l induced apoptosis significantly increase the percentage of cells in Sub-G1 phase in the absence of necrosis. Consistent with these results, caspase-3/7 assay revealed that 5l presents pro-apoptotic activity due to the significant stimulation of caspases-3/7. Moreover, 5a, 5l and 5p increased antioxidant defense and decreased reactive oxygen species (ROS) production. Conclusion: The compounds were synthesized with good yield and three of these presented (5a, 5l and 5p) good cytotoxicity against C6 cell line. Both affected cell cycle distribution via arresting more C6 cell line at Sub-G1 phase promoting apoptosis. Furthermore, 5a, 5l and 5p modulated redox status. These findings suggest that these compounds can be considered as promising lead molecules for further development of potential antitumor agents.

Biological Efficacy of Essential Oils and Plant Extracts of Cultivated and Wild Ecotypes of Origanum vulgare L.

Current study describes discrepancy in biological efficacy of methanolic and ethanolic extracts and essential oil procured from cultivated and wild accessions of Origanum vulgare. Simultaneously, quantification of carvacrol, thymol, caryophyllene, ocimene, and terpinen-4-ol contents was determined via GC-MS and GC in both accessions. The results revealed significantly a higher antioxidant potential by methanolic extracts displaying IC50 of 19.9 μg/ml compared to essential oil with IC50 of 10 μg/ml, and ethanolic extracts were found to be less effective even at the concentration of 3 μg/ml. However, essential oil from wild and cultivated accessions of O. vulgare exhibited significantly high antimicrobial activity against all 39 bacteria, 16 fungi, and 2 yeast species tested due to higher concentrations of carvacrol and thymol as revealed by GC analysis. Inhibition of tyrosinase activity in a C6 cell line displayed 81.0%–87.0% depigmentation potential of the methanolic extracts, while ethanolic extracts revealed a maximum of 88.54–99.02% inhibition of reactive oxygen species (ROS) in H2O2-treated cells. Hence, the study determines efficacy of essential oil against microbial pathogenesis, methanolic extracts as potent depigmentation agents, and ethanolic extracts as potent free radical scavenger.

P2Y1 nucleotide receptor silencing and its effect on glioma C6 calcium signaling.

In our earlier studies of the signaling cross-talk between nucleotide receptors in an in vitro glioma model (C6 cell line) under prolonged serum deprivation conditions, a growth arrest of the cells and expression shift from P2Y(1) to P2Y(12) receptors was found. The aim of the present work was to test if siRNA silencing of P2Y(1) receptor changes P2Y(12) expression similarly as following the serum deprivation and which physiological downstream pathways it affects. Here we demonstrate for the first time the efficiency of siRNA technology in silencing P2Y nucleotide receptors in glioma C6 cell line. Moreover, P2Y(12) proved to be insensitive to the P2Y(1) receptor silencing. The effect of the P2Y(1) silencing on calcium signaling was less pronounced then the extent of the protein change itself, exactly as was the case for the serum starvation experiments. Phosphorylation of ERK and Akt kinases were studied as the downstream effect of P2Y(1)-evoked signaling and similar effects as in the case of serum deprivation were found for ERK, and even stronger ones for Akt phosphorylation.