Ficus carica latex prevents invasion through induction of let-7d expression in GBM cell lines.

Glioblastoma multiforme (GBM) is one of the deadliest human malignancies. A cure for GBM remains elusive, and the overall survival time is less than 1 year. Thus, the development of more efficient therapeutic approaches for the treatment of these patients is required. Induction of tumor cell death by certain phytochemicals derived from medicinal herbs and dietary plants has become a new frontier for cancer therapy research. Although the cancer suppressive effect of Ficus carica (fig) latex (FCL) has been determined in a few cancer types, the effect of this latex on GBM tumors has not been investigated. Therefore, in the current study, the anti-proliferative activity of FCL and the effect of the FCL-temozolomide (TMZ) combination were tested in the T98G, U-138 MG, and U-87 MG GBM cell lines using the WST-1 assay. The mechanism of cell death was analyzed using Annexin-V/FITC and TUNEL assays, and the effect of FCL on invasion was tested using the chick chorioallantoic membrane assay. To determine the effect of FCL on GBM progression, the expression levels of 40 GBM associated miRNAs were analyzed in T98G cells using RT-qPCR. According to the obtained data, FCL causes cell death in GBM cells with different responses to TMZ, and this effect is synergistically increased in combination with TMZ. In addition, the current study is the first to demonstrate the effect of FCL on modulation of let-7d expression, which may be an important underlying mechanism of the anti-invasive effect of this extract.

Optimization and validation of ultrasensitive GC-MS/MS method to measure oxidatively induced DNA damage products and role of antioxidants in oxidation mechanism.

Oxidation of DNA due to exposure to reactive oxygen species (ROS) is a major source of DNA damage. ROS induced damage to DNA plays an important role in some diseases such as various cancers, aging and neurodegenerative diseases. The detection of DNA oxidation products plays a major role in assessing the mutagenicity potential of specific exposure. The GC-MS/MS method was developed for the ultrasensitive determination of individual DNA damage products. The validation results revealed that the proposed method was reliable and sensitive. Multiple response surface methodology (MRSM) was used to optimize derivatization conditions of oxidatively DNA base damage products before GC-MS/MS analysis. The optimum derivatization conditions were determined as 40 min for derivatization time, 120 °C for derivatization temperature and 1.4 for BSTFA/pyridine ratio under nitrogen atmosphere. The effects of thymol, carvacrol and thymoquinone as antioxidants were investigated on oxidative DNA damage. The determination of the oxidatively induced DNA damage products was performed after adding DNA and antioxidants with different concentrations under oxidative stress. Eighteen DNA base damage products were analyzed simultaneously using GC-MS/MS. This study showed a significant decrease in the amount of DNA base damage products when the antioxidants were present in the medium.

Investigation of antioxidant ability of grape seeds extract to prevent oxidatively induced DNA damage by gas chromatography-tandem mass spectrometry.

Phenolic compounds have been studied elaborately for their efficacy to improve health and to protect against a wide variety of diseases. Herein this study, different analysis methods were implemented to evaluate the antioxidant properties of catechin and cyanidin using their standard substances and as they found in the grape seeds extracts. Total phenol contents were 107.39±8.94mg GAE/g dw of grape seeds for grape seed extract (GSE) and 218.32±10.66mg GAE/g dw of grape seeds for acid-hydrolyzed grape seed extract (AcGSE). The extracts were analyzed by HPLC-DAD system and the results showed the presence of catechin, gallic acid, chlorogenic acid and ellagic acid in the processed methanolic extract and cyanidin, gallic acid and ellagic acid in the processed acidified methanolic extract. The protective abilities of catechin and cyanidin were tested against the oxidation of DNA. The results showed that cyanidin has better protection of DNA against oxidation than catechin. GSE and AcGSE were revealed to inhibit the oxidatively induced DNA damage. GSE decreased about 57% of damage caused by the Fenton control sample. This study could show new aspects of the antioxidant profiles of cyanidin and catechin.

Quantification of DNA damage products by gas chromatography tandem mass spectrometry in lung cell lines and prevention effect of thyme antioxidants on oxidative induced DNA damage.

Lung cancer has a high treatment cost and poor prognosis in comparison to other types of cancers. This work was involved in studying oxidative DNA base damage inhibition. Accordingly, standard carvacrol, thymol, thymoquinone with water and water-methanol extract of thyme (Origanum vulgare L. subsp. hirtum (link.) Ietswaart), thyme oil and thyme water were prepared and investigated for their efficacy to inhibit DNA oxidative damage formed by H2O2 in malignant lung cells (A549). The antioxidant capacity by ABTS assay was 271.73 ±â€¯11.45 mg trolox equivalent/mL for thyme oil. HPLC analysis was carried out to determine the contents of different thyme extracts, results showing the presence of carvacrol, thymol, protocatechuic acid, caffeic acid, epicatechin and rosmarinic acid in water and water-methanol extracts while only carvacrol and thymol were found in thyme oil and thyme water. After DNA isolation from the cultured cells, the formed oxidative induced DNA damage products were analysed using GC-MS/MS. It was proven that the antioxidants in the cell culture media have succeeded to inhibit oxidative DNA base damage. Thymoquinone was shown to be the best protectant antioxidant among other antioxidants against the formation of oxidative DNA damage, whereas water-methanol extract of thyme was the best among the plant-sourced samples. Thymoquinone and thyme water-methanol extract were investigated for their efficacy on cultured healthy lung cells (BEAS-2B), and it was proven that they are efficient in protection against the oxidation of DNA of healthy lung cells too.

Ultrasensitive determination of DNA oxidation products by gas chromatography-tandem mass spectrometry and the role of antioxidants in the prevention of oxidative damage.

Oxidative stress is considered as one of the significant causes of DNA damage which in turn contributes to cell death through a series of intermediate processes such as cancer formation, mutation, and aging. Natural sources such as plant and fruit products have provided us with interesting substances of antioxidant activity that could be recruited in protecting the genetic materials of the cells. This study is an effort to discover some of those antioxidants effects in their standard and natural forms by performing an ultrasensitive determination of the products of DNA oxidation using GC-MS/MS. Experiments were used to determine the direct antioxidant activity of the substances contained in the tendrils of Vitis vinifera (var. alphonse) by extracting them and achieving Folin-Ciocalteau and CHROMAC analyses to determine the total phenolic content (TPC) and the antioxidant capacity of the extract, respectively; results revealed a phenolic content of 11.39±0.30mg Gallic Acid Equivalent (GAE)/g of the plant's fresh weight (FW) by Folin-Ciocalteau and 8.17±0.49mg Trolox Equivalent (TE)/g FW by CHROMAC assays. The qualitative analysis of the plant extract by HPLC-DAD technique revealed that two flavonoid glycosides namely rutin and isoquercitrin in addition to chlorogenic acid were contained in the extract. The determination of the DNA oxidation products was performed after putting DNA, rutin and isoquercitrin standard samples with different concentration, and the extract's sample under oxidative stress. Eighteen DNA oxidation products were traced using GC-MS/MS with ultra-sensitivity and the experiments proved a significant decrease in the concentration of the DNA oxidation products when the extract was used as a protectant against the oxidative stress. It is believed by conclusion that the extract of V. vinifera's (var. alphonse) tendrils has a good antioxidant activity; hence it is recommended to be used as a part of the daily healthy food list if possible.

Prediction of total antioxidant activity of Prunella L. species by automatic partial least square regression applied to 2-way liquid chromatographic UV spectral images.

Four different data representations were evaluated for the determination of the total antioxidant activities of four different Prunella L. species, which are Prunella vulgaris, Prunella grandiflora, Prunella laciniata, and Prunella orientalis Bornm. Three different antioxidant assays, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABST), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and Folin-Ciocalteu (FC) reagent measured the total antioxidant activity and phenolic content of the four Prunella L. species that were extracted with 12 different solvent systems. The data set of 48 Prunella L. extracts was collected by high-performance liquid chromatography (HPLC) with ultraviolet diode array detection. The prediction of total antioxidant activity of Prunella L. species by super partial least square (sPLS) regression was obtained using four different representations of the data; the entire two-way chromatographic-spectral images, the average UV spectra, the total absorbance chromatogram, the lambda max (λmax) chromatogram. The coefficients of determination (R2) for the entire two-way chromatographic-spectral images (the ABST (0.943±0.008), the DPPH (0.91±0.01), and the FC (0.963±0.006)) indicated good accuracy for predicting antioxidant activities. The three different wet chemical assays are known to yield different values so it is advantageous to estimate the three separate values with a single LC measurement. The entire two-way chromatographic-spectral images have been used to the first time for calibration. Acidic hexane, as an extraction solvent, gave the least root mean square error of prediction (RMSEP) for the two-way chromatographic-spectral images, so it would be the best solvent for modeling antioxidant activities.

Antioxidant and Antimicrobial Potential, and HPLC Analysis of Stictic and Usnic Acids of Three Usnea Species from Uludag Mountain (Bursa, Turkey).

In this study, antioxidant and antimicrobial potentials of Usnea intermedia, U. filipendula, and U. fulvoreagens and their stictic and usnic acid contents were investigated. Antioxidant activity and total phenolic contents were evaluated in acetone, ethanol, and methanol extracts of these three species. Antioxidant activity was measured by ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)] method and total phenolic contents were measured by Folin-Ciocalteu method. High-performance liquid chromatography (HPLC) was used for the determination of lichen acids. It can be concluded from stictic and usnic acids contents that the order of solvent efficiency is acetone > ethanol > methanol and acetone > methanol > ethanol, respectively. Broth microdilution method was performed to determine the minimum inhibitory concentration (MIC) of the methanol extracts of three Usnea species. The MIC values of all the extracts ranged from 64 µg/mL to 512 µg/mL for all the bacterial strains that were tested in this study, and all the Fluoro quinolone-resistant Escherichia coli isolates (except for E101) were sensitive to the methanol extracts of the three Usnea species. This paper is the first study to determine the stictic acid content in U. intermedia and U. filipendula. Our findings indicate that these three Usnea species could be used as antioxidant and antimicrobial agents.

Olea europaea leaf extract improves the treatment response of GBM stem cells by modulating miRNA expression.

The stem-like cells of Glioblastoma multiforme (GBM) tumors (GSCs) are one of the important determinants of recurrence and drug resistance. The aims of the current study were to evaluate the anticancer effect of Olea europaea leaf extract (OLE) on GBM cell lines, the association between OLE and TMZ responses, and the effect of OLE and the OLE-TMZ combination in GSCs and to clarify the molecular mechanism of this effect on the expression of miRNAs related to cell death. The anti-proliferative activity of OLE and the effect of the OLE-TMZ combination were tested in the T98G, U-138MG and U-87MG GBM cell lines using WST-1 assay. The mechanism of cell death was analyzed with Annexin V/FITC and TUNEL assays. The effects of OLE on the expression levels of miR-181b, miR-153, miR-145 and miR-137 and potential mRNA targets were analyzed in GSCs using RT-qPCR. OLE exhibited anti-proliferative effects via apoptosis and necrosis in the GBM cell lines. In addition, OLE significantly induced the expression of miR-153, miR-145, and miR-137 and decreased the expression of the target genes of these miRNAs in GSCs (p < 0.05). OLE causes cell death in GBM cells with different TMZ responses, and this effect is synergistically increased when the cells are treated with a combination of OLE and TMZ. This is the first study to indicate that OLE may interfere with the pluripotency of GSCs by modulating miRNA expression. Further studies are required, but we suggest that OLE may have a potential for advanced therapeutic cancer drug studies in GBM.

Development of a new chromium reducing antioxidant capacity (CHROMAC) assay for plants and fruits.

A chromium reducing antioxidant capacity (CHROMAC) assay was presented to measure antioxidant capacity of selected plants and fruits and compared its performance with other commonly used antioxidant capacity methods of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and cupric reducing antioxidant capacity (CUPRAC). The assay is based on the spectrophotometric measurement of colored a chelate complex of Cr(III) and diphenylcarbazone formed by the reaction of Cr(VI) and 1,5-diphenylcarbazid in acidic medium. Phenolic compounds react with excessive amounts of Cr(VI) at low pH values, causing reduction of Cr(VI) to Cr(III) and conversion of phenols to oxidized products. The assay comprises of the antioxidant with a chromium(VI) solution, a 1,5-diphenylcarbazid in acidic medium and subsequent measurement of the developed absorbance at 540 nm after 50 min. The color development is stable for phenolic compounds in plant and fruit. The selectivity of the assay for phenolic compounds was improved by adjusting pH to 2.8 and reduction potential between 0.2 and 0.9 V. The developed assay was successfully applied to the measurement of antioxidant capacity of three plants and one fruit (Prunus divaricata Ledeb.subsp. divaricata) samples and comparable results were obtained by ABTS and CUPRAC assays.

Determination of phenolic compounds in Prunella L. by liquid chromatography-diode array detection.

Four species of Prunella L. (Prunella vulgaris L., Prunella laciniata L., Prunella grandiflora L. and Prunella orientalis Bornm.) belong to the family of Lamiaceae and representing popular Western and Chinese herbal medicine were examined for the content of phenolic compounds. Phenolic acids (rosmarinic acid, caffeic acid, ferulic acid, chlorogenic acid, protocatechuic acid), flavonoids (rutin, quercetin) in different quantitative proportions depending on extracts were determined by the rapid, selective and accurate method combining solvent/acid hydrolysis extraction and high performance liquid chromatography-diode array detection (HPLC-DAD). Water, methanol, butanol, acetonitrile, ethyl acetate, hexane and their acidic solutions were used to examine the efficiency of different solvent systems for the extraction of phenolic compounds. Acid hydrolysis extraction was established as the most suitable extraction method for phenolic compounds.

Phenolic content and antioxidant activity of raspberry and blackberry cultivars.

Raspberry (Aksu Kirmizisi, Rubin, Newburgh, Hollanda Boduru, Heritage) and blackberry (Bursa 1, Bursa 2, Jumbo, Chester) cultivars were assayed for antioxidant activity (determined as 2,2-azino-di-[3-ethylbenzothialozine-sulphonic acid][ABTS], 2,2-diphenyl-1-picrylhydrazyl radical [DPPH], and cupric ion reducing antioxidant capacity [CUPRAC]), total phenol, total flavonoid, and total anthocyanin contents. In addition, 10 anthocyanins and anthocyanidins were determined in raspberry and blackberry by liquid chromatography-mass spectrometry (LC-MS/MS). Raspberry and blackberry had the highest ABTS, DPPH, CUPRAC, total phenol, and total flavonoid contents in methanol extracts, whereas total anthocyanin contents were the highest in water extracts. The antioxidant activity of the raspberry and blackberry was directly related to the total amount of phenolic compounds detected in the raspberry and blackberry. All antioxidant activity values were highly correlated with anthocyanin content in blackberry (0.93 < or = r < or = 0.99, P = 0.05). On the other hand, high correlation between total flavonoid content and antioxidant activity was recorded in water extract of blackberry (0.91 < or = r < or = 0.93, P = 0.05). ABTS value was highly correlated with total flavonoid content in methanol extract (r = 0.90), whereas total flavonoid content was relatively less correlated with DPPH (r = 0.85) and CUPRAC (r = 0.89).

Net analyte signal-based simultaneous determination of dyes in environmental samples using moving window partial least squares regression with UV-vis spectroscopy.

The multivariate calibration methods-moving window selection partial least squares regression (MWPLSR) and net analyte signal (NAS)-were employed for simultaneous determination of a mixture of C.I. Disperse Blue 183, C.I. Disperse Blue 79, C.I. Disperse Red 82, C.I. Disperse Red 65, C.I. Disperse Yellow 211 and C.I. Disperse Orange 25 by UV-vis spectrophotometry. The absorption spectra of the six disperse dyes were recorded between 320 and 680 nm. A modified changeable size moving window partial least squares (CSMWPLS) and searching combination moving window partial least squares (SCMWPLS) were proposed to search for an optimized spectral interval and an optimized combination of spectral regions from informative regions obtained by MWPLSR. Different wavelength regions were selected by taking into account different spectral parameters including the starting wavelength, the ending wavelength and wavelength interval. It was found that wavelength selection improved the performance of the corresponding net analyte signal-partial least squares (NAS-PLS) model, in terms of root mean square error (RMSE), compared with the results obtained using whole spectra or direct combination of informative regions for each dye. The importance of calibration design was also investigated by calculating the prediction and validation errors. The influence of using independent validation sets were emphasized. The proposed calibration method gave better results in combination and informative spectral regions for determination of the six disperse dyes without prior separation.

Principal component analysis and cluster analysis for the characterisation of marbles by capillary electrophoresis.

Chemical characterisation has been carried out on 25 quarry marbles collected from Marmara, Aegean and Thrace regions of Turkey. Ten elements were determined by capillary electrophoresis (CE). Principal component analysis and cluster analysis techniques were utilised to define grouping of different marble samples. These techniques showed that the analysed marbles were differentiable mainly by provenance. Experimental conditions such as pH, applied voltage and concentration of alpha-hydroxyisobutyric acid (HIBA) were optimised to achieve the best separation of metal ions using central composite design. The optimum pH 3.7, applied voltage 15kV and concentration of HIBA 10mM were found to provide the best separation for all metal ions investigated.