, J. H. , Jeon , Y. J. , Bang , W. , Cho , J. J. , Choi , N. J. , Seo , K. S. , Shim , J. H. , Chae , J. I. ( 2015 ) Quercetin induces antiproliferative activity against human hepatocellular carcinoma (HepG2) cells by suppressing
of their nutritional properties ( Kubota et al., 2012 ). In our study, antioxidant activities, antimicrobial activities, and antiproliferative effects of A. acutifolius and A. officinalis plants were investigated. In this context, it is aimed to
Lichens are a symbiotic relationship between a fungus and a photosynthetic partner. Chemical characterization and bioactive potentials (antiproliferative, antioxidant, and antibacterial) of five lichen species (Evernia prunastri, Platismatia glauca, Pseudevernia furfuracea, Ramalina fastigiata, and Ramalina farinacea) were assessed. Five lichen metabolites (usnic acid, atranorin, stictic acid, evernic acid, and fumarprotocetraric acid) were analyzed by HPLC-DAD. E. prunastri was noteworthy evernic acid source. Antiproliferative activity was evaluated using human breast adenocarcinoma (MCF-7) and human hepatocellular carcinoma (HepG2/C3A) cell lines. The strongest activity was observed for P. glauca against HepG2/C3A, while the only lichen species that induced cytotoxicity against MCF-7 cell line was P. furfuracea. The highest antioxidant activity was also obtained with P. furfuracea. E. prunastri and R. farinaceae had the highest phenolic and flavonoid contents, respectively. Antibacterial activities of the extracts were determined against ten pathogenic bacteria. The most effective antibacterial agent was methanol extract of R. fastigiata. Our findings have revealed the pharmaceutical potentials of tested lichen species.
The aim of the present study was to investigate the biological activities of Tunisian olive leaf extracts and to correlate these activities to their phytochemical composition. The phenolic profile of four Tunisian autochthonous cultivars Chemlali, Sayali, Neb jmel, and Meski was determined using LC/MS-MS. The antioxidant activity of olive leaf extracts was evaluated using DPPH test. The antiproliferative effect was also investigated using MTT assay. The phytochemical screening showed that phenolic content and phenolic class repartition were significantly affected by olive leaf cultivars. Twenty-one components were identified and oleurpein, luteolin 4-glucoside, luteolin 7-glucoside, and apigenin 7-glucoside were the major phenolic components. Among all extracts, Sayali exhibited the strongest antioxidant and antiproliferative activities (IC50 41.36 µg ml−1 / EC50 147.11 µg ml−1). The MTT result showed that olive leaf extract reduced MCF-7 cell viability in a dose-dependent manner. Western blot analysis demonstrated that olive leaf extracts exhibited antiproliferative activity through apoptosis induction.
Sera from 86 patients with chronic hepatitis C virus (HCV) infection treated with recombinant interferons-a (rIFN-a) were screened for IFN-binding and antiviral effect-neutralizing antibodies. Out of the 61 patients treated with rIFN-a2b, 46% had binding and 28% had neutralizing antibodies. 44% of the 25 patients treated with rIFN-a2a developed binding antibodies and 24% had neutralizing antibodies. Contradictory data were observed concerning the appearance of anti-IFN antibodies and the outcome of IFN therapy. A significantly higher number of the patients with a sustained response to rIFN-a2b therapy formed antibodies than the number among the non-responder patients. At the same time, in the patients treated with rIFN-a2a, opposite data were found. The activity of the antibodies in some sera was studied against the antiproliferative effect of IFNs on Daudi cells by measuring the [3H]thymidine incorporation. The binding antibodies without neutralization of the antiviral effect of the IFNs inhibited the antiproliferative activity of the rIFNs, similarly to antibodies having both IFN-binding and antiviral effect-neutralizing capacities. At the same time, the antiproliferative effect of the natural IFN was less affected. It is suggested that the antiproliferative assay is more sensitive than the antiviral method for demonstration of the presence of antibodies exerting an inhibitory effect on the biological activities of IFN.
The relationship of plasma membrane biophysical properties to the antiproliferative effect of interferon-alpha (IFN-a) was investigated in Daudi lymphoblasts cell lines with sensitivity to growth inhibition, parallel clonal variants selected for resistance, and one revertant subclone. Lateral mobility of surface differentiation antigens (I2, CD19, CD20, and sIgM-k) were measured by fluorescence recovery after photobleaching (FRAP). The mean diffusion coefficients, D, values for two clones of IFN-a resistant Daudi cells were significantly higher (D = 8.1-11 × 10-10 cm2/sec) than for parental sensitive cells (D = 4.9-7.4 × 10-10 cm2/sec). Microviscosity of the plasma membranes were probed by electron spin resonance (ESR) spectrometry. These results also indicate a greater degree of molecular motional freedom in resistant cells. Treatment of sensitive lymphoblasts with IFN-a (100-400 U/106 cells) for 5-30 min consistently increased mean values of D and the degree of spin-probe motional freedom, whereas no significant differences were detected in resistant cells. The effect of IFN-a on the membrane potential (Em) of Daudi cells was quantitated by flow cytometry using a voltage-sensitive oxonol dye. Membrane potential of all clones was similar (-50 to -56 mV). Treatment with IFN-a for 8-10 min caused hyperpolarization in the sensitive cells (DEm up to 45 mV), but only minimal hyperpolarization in the resistant ones (DEm up to 7 mV). We concluded that sensitivity to IFN-a and treatment with IFN-a are related to the biophysical status of plasma membranes.
A group of thirteen newly synthesized potential herbicides,
-aryltrichloroacetamides or 2-(chlorophenoxy)acyl derivatives, have been initially investigated by reversed phase (RP) TLC. The lipophilicity of the substances was described by retention factors in water, log
, calculated from experimental RP TLC data, and by log
values calculated by use of software. Biological activity was examined by use of the BioArena system of TLC separation then (micro)biological detection. The potential role of formaldehyde (HCHO) in the toxic antibacterial action of substances against
bacterial cells was investigated. The effect of HCHO capturers (L
-arginine and reduced glutathione) and Cu
ions on the bioactivity and mechanism of toxicity of the substances was examined. It was established that HCHO and its potential reaction products (e.g.
) are crucial in the mechanism of action of these molecules. Correlations between the lipophilicity and bioactivity of the test compounds were also analyzed. It seems that hydrophobicity is not the decisive factor affecting the bioactivity of these substances.