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Four neutral Rh1-Rh4 complexes of the general formula [Rh 2 (CH 3 COO) 4 L 2 ], where L is an N -alkylimidazole ligand, were synthesized and characterized using various spectroscopic techniques, and in the case of Rh4 the crystal structure was confirmed. Investigation of the interactions of these complexes with HSA by fluorescence spectroscopy revealed that the binding constants K b are moderately strong (∼10 4 M -1 ), and site-marker competition experiments showed that the complexes bind to Heme site III (subdomain IB). Competitive binding studies for CT DNA using EB and HOE showed that the complexes bind to the minor groove, which was also confirmed by viscosity experiments. Molecular docking confirmed the experimental data for HSA and CT DNA. Antimicrobial tests showed that the Rh2-Rh4 complexes exerted a strong inhibitory effect on G + bacteria B. cereus and G - bacteria V. parahaemolyticus as well as on the yeast C. tropicalis different mechanisms of action, namely apoptosis (increase in expression of the pro-apoptotic Bax protein and caspase-3 protein in HeLa and HCT116 cells; changes in mitochondrial potential and mitochondrial damage; release of cytochrome c from the mitochondria; cell cycle arrest in G2/M phase in both HeLa and HCT116 cells together with a decrease in the expression of cyclin A and cyclin B) and autophagy (reduction in the expression of the protein p62 in HeLa and HCT116 cells).via different mechanisms of action, namely apoptosis (increase in expression of the pro-apoptotic Bax protein and caspase-3 protein in HeLa and HCT116 cells; changes in mitochondrial potential and mitochondrial damage; release of cytochrome c from the mitochondria; cell cycle arrest in G2/M phase in both HeLa and HCT116 cells together with a decrease in the expression of cyclin A and cyclin B) and autophagy (reduction in the expression of the protein p62 in HeLa and HCT116 cells).

Six new dinuclear Pd(II) complexes, [{Pd(2,2'-bipy)Cl} 2 (μ-pz)](ClO 4 ) 2 (Pd1), [{Pd(dach)Cl} 2 (μ-pz)](ClO 4 ) 2 (Pd2), [{Pd(en)Cl} 2 (μ-pz)](ClO 4 ) 2 (Pd3), [{Pd(2,2'-bipy)Cl} 2 (μ-4,4'-bipy)](ClO 4 ) 2 (Pd4), [{Pd(dach)Cl} 2 (μ-4,4'-bipy)](ClO 4 ) 2 (Pd5) and [{Pd(en)Cl} 2 (μ-4,4'-bipy)](ClO 4 ) 2 (Pd6) (where 2,2'-bipy=2,2'-bipyridyl, pz=pyrazine, dach=trans-(±)-1,2-diaminocyclohexane, en=ethylenediamine, 4,4'-bipy=4,4'-bipyridyl) have been synthesized and characterized by elemental microanalysis, IR, 1 H NMR and MALDI-TOF mass spectrometry. The pK a values of corresponding diaqua complexes were determined by spectrophotometric pH titration. Substitution reactions with thiourea (Tu), l-methionine (l-Met), l-cysteine (l-Cys), l-histidine (l-His) and guanosine-5'-monophosphate (5'-GMP) were studied under the pseudo-first order conditions at pH7.2. Reactions of Pd1 with Tu, l-Met and l-Cys were followed by decomposition of complexes, while structures of dinuclear complexes were preserved during the substitution with nitrogen donors. Interactions with calf-thymus DNA (CT-DNA) were followed by absorption spectroscopy and fluorescence quenching measurements. All complexes can bind to CT-DNA exhibiting high intrinsic binding constants (K b =10 4 -10 5 M -1 ). Competitive studies with ethidium bromide (EB) have shown that complexes can displace DNA-bound EB. High values of binding constants towards bovine serum albumin protein (BSA) indicate good binding affinity. Finally, all complexes showed moderate to high cytotoxic activity against HeLa (human cervical epithelial carcinoma cell lines) and MDA-MB-231 (human breast epithelial carcinoma cell lines) tumor cell lines inducing apoptotic type cell death, whereas normal fibroblasts were significantly less sensitive. The impact on cell cycle of these cells was distinctive, where Pd4, Pd5 and Pd6 showed the most prominent effect arresting MDA-MB-231 (human lung fibroblast cell lines) cell in G1/S phase of cell cycle., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Apoptosis is a highly regulated and programmed cell breakdown process characterized by numerous changes. Since it is implicated in many pathological as well as physiological processes, it is vital to have reliable methods for detecting cell death. In this study, we compared several methods for detecting apoptosis and necrosis in human leukocytes. Apoptosis was induced either by incubating the cells with various doses of cycloheximide (CHX) or by 312 nm UVB irradiation. The methods used for detecting apoptosis were light microscopy (May Grunwald-Giemsa and trypan blue staining), fluorescence microscopy (acridin orange/ethidium bromide and annexin V/propidium iodide staining) and agarose gel electrophoresis of fragmented genomic DNA. Our study showed that CHX-induced apoptosis in cultured peripheral blood mononuclear cells but had no effect on apoptosis in polymorphonuclear cells, so its effect depends on cell type. Evaluation and comparison of the methods for detecting apoptosis showed the following. A Giemsa-stained cytospin allows the main morphological characteristics of necrotic and apoptotic death to be recognized. Trypan blue staining, widely used for estimating cell viability, is valueless for detecting apoptosis. Both fluorescence methods provided reliable and reproducible results and distinguished clearly between subpopulations of apoptotic cells, and were closely intercorrelated. Although applicable to a wide spectrum of cell types, agar electrophoresis of extracted DNA cannot be applied to all cell types and apoptotic conditions. Generally, microscopic examination of acridin orange/ethidium bromide stained cells can be recommended as the most reliable of the methods tested.

As cancer remains a significant global health challenge, there is an increasing need for novel therapeutic approaches. We investigated the antitumor potential of Juniperus communis berry essential oil on cervical cancer HeLa and colorectal HCT 116 cells. Cytotoxicity was evaluated through the MTT assay, revealing concentration-dependent reductions in cell viability. A clonogenic assay demonstrated long-term cytotoxic effects. Apoptosis markers were assessed via flow cytometric analysis and showed an induction of the intrinsic pathway in both cell lines, demonstrated by the elevated levels of cleaved caspase-3, Bax/Bcl-2 ratio, JC-10 monomer formation, and cytochrome C migration to the cytosol. The treatment inhibited cell-survival pathways in HCT 116 cells and arrested HeLa cells in the S phase. An extensive molecular docking screening provided insight into the binding affinity and interaction patterns of the essential oil components with NADH ubiquinone oxidoreductase and superoxide dismutase enzymes, further confirming the induction of the intrinsic pathway of apoptosis. The obtained in silico and in vitro results indicated the anticancer potential of J. communis berry essential oil as it interferes with cancer cell molecular mechanisms. Our findings highlight J. communis berry essential oil as a promising natural agent with anticancer potential. [ABSTRACT FROM AUTHOR]

Chalcones, as a large group of organic compounds, are widely implemented in various types of anticancer therapeutics. These plant metabolites are present in fruits, vegetables, spices, and have anti-tumor, antiinflammation, immunomodulation, antibacterial and anti-oxidative activities, as well as many other pharmacological and biological effects. The aim of the present study was to investigate cytotoxic effects, type of cell death and mechanism of action of the newly synthesized vanillin based chalcone analogs, (CH1) and (CH2) on human colon cancer HCT-116 and noncancerous (control) MRC-5 cell lines. In order to compare the effects of vanillin based chalcone analogs on investigated cell lines, as reference substances cisplatin (cisPt) and dehydrozingerone (DHZ) were used. Investigation of antitumor effect of chalcone analogs on HCT-116 cells was carried out by three methods MTT assay, flow cytometry and immunofluorescence analysis. The result of our investigation indicated that newly synthesized vanillin based chalcone analogs expressed powerful antitumor effect on cancer cells (HCT-116 cell line), while their effect on healthy cells (MRC-5 cell line) was not statistically significant. Vanillin based chalcone analogs caused overexpression and activation of mitochondrial Bax protein and caspase-3 in HCT-116 cells, indicating that their mechanism of antitumor action was mediated through activation of the inner apoptotic pathway. These results indicate possible usefulness of CH1 and CH2 in antitumor therapy whether through its direct cytotoxic effect or as adjuvant therapy. Our results indicate possible usefulness of CH1 and CH2 vanillin based chalcone analogs in antitumor therapy. [ABSTRACT FROM AUTHOR]

A serie of novel square pyramidal copper(ii) complexes [Cu(L)2H2O] (3a–d) with O,O-bidentate ligands [L = ethyl-2-hydroxy-4-aryl-4-oxo-2-butenoate; aryl = 3-methoxyphenyl-2a, (E)-2-phenylvinyl-2b, (E)-2-(4′-hydroxy-3′-methoxyphenyl)vinyl-2c, 3-nitrophenyl-2d, 2-thienyl-2e] were synthesized and characterized by spectral (UV-Vis, IR, ESI-MS and EPR), elemental and X-ray analysis. The antimicrobial activity was estimated by the determination of the minimal inhibitory concentration (MIC) using the broth microdilution method. The most active antibacterial compounds were 3c and 3d, while the best antifungal activity was showed by complexes 3b and 3e. The lowest MIC value (0.048 mg mL−1) was measured for 3c against Proteus mirabilis. The cytotoxic activity was tested using the MTT method on human epithelial carcinoma HeLa cells, human lung carcinoma A549 cells and human colon carcinoma LS174 cells. All complexes showed extremely better cytotoxic activity compared to cisplatin at all tested concentrations. Compound 3d expressed the best activity against all tested cell lines with IC50 values ranging from 7.45 to 7.91 μg mL−1. The type of cell death and the impact on the cell cycle for 3d and 3e were evaluated by flow cytometry. Both compounds induced apoptosis and S phase cell cycle arrest. The interactions between selected complexes (3d and 3e) and CT-DNA or bovine serum albumin (BSA) were investigated by the fluorescence spectroscopic method. Competitive experiments with ethidium bromide (EB) indicated that 3d and 3e have a propensity to displace EB from the EB–DNA complex through intercalation suggesting strong competition with EB [Ksv = (1.4 ± 0.2) and (2.9 ± 0.1) × 104 M−1, respectively]. Ksv values indicate that these complexes bind to DNA covalently and non-covalently. The achieved results in the fluorescence titration of BSA with 3d and 3e [Ka = (2.9 ± 0.2) × 106 and (2.5 ± 0.2) × 105 M, respectively] showed that the fluorescence quenching of BSA is a result of the formation of the 3d– and 3e–BSA complexes. The obtained Ka values are high enough to ensure that a significant amount of 3d and 3e gets transported and distributed through the cells. [ABSTRACT FROM AUTHOR]

Abstract: The toxicity of platinum(II) ion could be significantly modified by coordination with some organic compounds. In our study, the cytotoxicity and the influence of platinum(II) complexes, such as cisplatin, cis-[PtCl2(NH3)2], [PtCl2(SMC)] and [PtCl2(DMSO)2] (where SMC is S-methyl-l-cysteine and DMSO is dimethyl sulphoxide) on spontaneous motility of isolated human fallopian tubes were investigated. Cisplatin showed potent pro-apoptotic effects on peripheral blood mononuclear cells (PBMC). However, peripheral blood mononuclear cells were substantially less sensitive to [PtCl2(SMC)] and [PtCl2(DMSO)], and these compounds showed no toxic effect on PBMC in all concentrations examined. Cisplatin showed concentration-dependent inhibition of spontaneous contractions of the isolated ampulla. (EC50 =1.14±0.03×10−6 M/l, r =0.714, p <0.05) while [PtCl2(SMC)] and [PtCl2(DMSO)2] did not affect spontaneous contractions of isolated fallopian tube ampulla. [Copyright &y& Elsevier]