Mononuclear metal complexes with Piroxicam: Synthesis, structure and biological activity

Synthesis, characterization, molecular modeling studies, and biological evaluation of metal piroxicam complexes (M = Ni(II), Pt(IV), Pd(II), Ag(I)) as antibacterial and anticancer agents

Four piroxicam metal complexes; NiL2 , PtL2 , PdL2 , and AgL were synthesized and characterized by different techniques with enhanced antibacterial and anticancer activity. Regarding in vitro antimicrobial activity, complex NiL2 displayed potent antibacterial effect against Escherichia coli and Pseudomonas aeruginosa that was 1.9-folds higher than piroxicam (minimum inhibitory concentration [MIC] = 31.85, 65.32 µM), respectively. In case of G+ve bacteria, complex PtL2 had potent activity on Staphylococcus aureus which was 2.1-folds higher than piroxicam (MIC = 43.12 µM), while activity of complex AgL against Enterococcus faecalis was threefolds higher than piroxicam (MIC = 74.57 µM. Complexes PtL2 and PdL2 exhibited higher inhibition of DNA gyrase than piroxicam (IC50  = 6.21 µM) in the range of 1.9-1.7-folds. The in vitro antiproliferative activity depicted that all investigated complexes showed better cytotoxic effect than piroxicam, specifically Pt and Pd complexes which had lower IC50 values than piroxicam on human liver cancer cell line HepG2 by 1.8 and 1.7-folds, respectively. While Pd and Ag complexes showed 2 and 1.6-folds better effect on human colon cancer cell line HT-29 compared with piroxicam. Molecular modeling studies including docking on Stranded DNA Duplex (1juu) and DNA gyrase enzyme (1kzn) that gave good insight about interaction of complexes with target molecules, calculation of electrostatic potential map and global reactivity descriptors were performed.

Transition Metal Complexes with Tridentate Schiff Bases (O N O and O N N) Derived from Salicylaldehyde: An Analysis of Their Potential Anticancer Activity

Although it is known that the first case of cancer was recorded in ancient Egypt around 1600 BC, it was not until 1917 during the First World War and the development of mustard gas that chemotherapy against cancer became relevant; however, its properties were not recognised until 1946 to later be used in patients. In this sense, the use of metallopharmaceuticals in cancer therapy was extensively explored until the 1960s with the discovery of cisplatin and its anticancer activity. From that date to the present, the search for more effective, more selective metallodrugs with fewer side effects has been an area of continuous exploration. Efforts have led to considering a wide variety of metals from the periodic table, mainly from the d-block, as well as a wide variety of organic ligands, preferably with proven biological activity. In this sense, various research groups have found an ideal binder in Schiff bases, since their raw materials are easily accessible, their synthesis conditions are friendly and their denticity can be manipulated. Therefore, in this review, we have explored the anticancer and antitumor activity reported in the literature for coordination complexes of d-block metals coordinated with tridentate Schiff bases (O N O and O N N) derived from salicylaldehyde. For this work, we have used the main scientific databases CCDC® and SciFinder®.

Synthesis, characterization and (in vitro and in silico) biological activity of a series of dioxouranium(VI) complexes with non-steroidal anti-inflammatory drugs

The reaction of the dioxouranium(VI) ion with a series of non-steroidal anti-inflammatory drugs (NSAIDs), namely mefenamic acid, indomethacin, diclofenac, diflunisal and tolfenamic acid, as ligands in the absence or presence of diverse N,N'-donors (1,10-phenanthroline,2,2'-bipyridine or 2,2'-bipyridylamine) as co-ligands led to the formation of ten complexes bearing the formulas [UO₂(NSAID-O,O')₂(O-donor)₂] or [UO₂(NSAID-O,O')₂(N,N'-donor)], respectively. The complexes were characterized with diverse spectroscopic techniques and the crystal structures of three complexes were determined by single-crystal X-ray crystallography. The biological profile of the resultant complexes was assessed in vitro and in silico. The in vitro studies include their antioxidant properties (ability to scavenge free radicals 1,1-diphenyl-picrylhydrazyl and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) and to reduce H₂O₂), their interaction with DNA (linear calf-thymus DNA or supercoiled circular pBR322 plasmid DNA) and their affinity for serum albumins (bovine and human serum albumin). In silico molecular docking calculations were performed regarding the behavior of the complexes towards DNA and their binding to both albumins.

Piroxicam Analogs: Design, Synthesis, Docking Study and Biological Evaluation as Promising Anti-HIV-1 agents

BACKGROUND

Taking the well-known drug, Piroxicam as a lead compound, we designed and synthesized two series of 1,2-benzothiazines 1,1-dioxide derivatives to assay their ability in inhibition of HIV-1 replication in cell culture.

OBJECTIVE

In this study, we describe the synthesis, docking study and biological evaluation of 1,2-benzothiazines 1,1- dioxide derivatives.

RESULTS

Most of the new compounds were active in the cell-based anti-HIV-1 assay with EC50 < 50 M. Among them, compounds 7g was found to be the most active molecule. Docking study using 3OYA pdb code on the most active molecule 7g with EC50 values of 10 M showed a similar binding mode to the HIV integrase inhibitors.

CONCLUSION

Since all the compounds showed no remarkable cytotoxicity (CC50> 500 M), the designed scaffold is promising structure for development of new anti-HIV-1 agents.

Metal-Based Scaffolds of Schiff Bases Derived from Naproxen: Synthesis, Antibacterial Activities, and Molecular Docking Studies

We report here the synthesis, characterization, and antibacterial evaluation of transition metal complexes of Ni, Cu, Co, Mn, Zn, and Cd (6a–f), using a Schiff base ligand (5) derived from naproxen (an anti-inflammatory drug) and 5-bromosalicylaldehyde by a series of reactions. The ligand and the synthesized complexes were characterized by elemental analysis, UV-Visible, FTIR, and XRD techniques. The ligand 5 behaves as a bidentate donor and coordinates with metals in square planar or tetrahedral fashion. In order to evaluate its bioactivity profile, we screened the Schiff base ligand and its metal complexes (6a–f) against different species of bacteria and the complexes were found to exhibit significant antibacterial activity. The complexes showed more potency against Bacillus subtilis as compared to the other species. Moreover, we modeled these complexes’ binding affinity against COX1 protein using computational docking.

Synthesis, spectral, DFT modeling, cytotoxicity and microbial studies of novel Zr(IV), Ce(IV) and U(VI) piroxicam complexes

The Zr(IV), Ce(IV) and U(VI) piroxicam anti-inflammatory drug complexes were prepared and characterized using elemental analyses, conductance, IR, UV-Vis, magnetic moment, ^IHNMR and thermal analysis. The ratio of metal: Pir is found to be 1:2 in all complexes estimated by using molar ratio method. The conductance data reveal that Zr(IV) and U(VI) chelates are non-electrolytes except Ce(IV) complex is electrolyte. Infrared spectroscopic confirm that the Pir behaves as a bidentate ligand co-ordinated to the metal ions via the oxygen and nitrogen atoms of ν(CO)_carbonyl and ν(CN)_pyridyl, respectively. The kinetic parameters of thermogravimetric and its differential, such as activation energy, entropy of activation, enthalpy of activation, and Gibbs free energy evaluated using Coats-Redfern and Horowitz-Metzger equations for Pir and complexes. The geometry of the piroxicam drug in the Free State differs significantly from that in the metal complex. In the time of metal ion-drug bond formation the drug switches-on from the closed structure (equilibrium geometry) to the open one. The antimicrobial tests were assessed towards some types of bacteria and fungi. The in vitro cell cytotoxicity of the complexes in comparison with Pir against colon carcinoma (HCT-116) cell line was measured.

New metal based drugs: spectral, electrochemical, DNA-binding, surface morphology and anticancer activity properties

The NSAID piroxicam (PRX) drug was used for complex formation reactions with Cu(II), Zn(II) and Pt(II) metal salts have been synthesized. Then, these complexes have been characterized by spectroscopic and analytical techniques. Thermal behavior of the complexes were also investigated. The electrochemical properties of all complexes have been investigated by cyclic voltammetry (CV) using glassy carbon electrode. The biological activity of the complexes has been evaluated by examining their ability to bind to fish sperm double strand DNA (FSFSdsDNA) with UV spectroscopy. UV studies of the interaction of the PRX and its complexes with FSdsDNA have shown that these compounds can bind to FSdsDNA. The binding constants of the compounds with FSdsDNA have also been calculated. The morphology of the FSdsDNA, PRX, metal ions and metal complexes has been investigated by scanning electron microscopy (SEM). To get the SEM images, the interaction of compounds with FSdsDNA has been studied by means of differential pulse voltammetry (DPV) at FSdsDNA modified pencil graphite electrode (PGE). The decrease in intensity of the guanine oxidation signals has been used as an indicator for the interaction mechanism. The effect of proliferation PRX and complexes were examined on the HeLA and C6 cells using real-time cell analyzer with four different concentrations.

Copper(ii) complexes of salicylaldehydes and 2-hydroxyphenones: synthesis, structure, thermal decomposition study and interaction with calf-thymus DNA and albumins

The characterized copper(ii) complexes with substituted salicylaldehydes and 2-hydroxyphenones exhibit enhanced affinity for DNA and albumins in comparison to free ligands.

In vitro changes in secretion activity of rat ovarian fragments induced by molybdenum

The aim of this in vitro study was to examine the secretion activity (progesterone, 17beta-estradiol and insulin-like growth factor-I) of rat ovarian fragments after molybdenum (Mo) addition. Rat ovarian fragments were incubated with ammonium molybdate (NH(4))(6)Mo(7)O(24).4H(2)O at the doses 90, 170, 330 and 500 microg.ml(-1) for 24 h and compared with control group without Mo addition. Release of progesterone (P(4)), estradiol (17beta-estradiol) and insulin-like growth factor I (IGF-I) by ovarian fragments was assessed by radioimmunoassay (RIA). Data show that P(4) release by ovarian fragments was not affected by (NH(4))(6).Mo(7)O(24).4H(2)O addition at all the doses used (90-500 microg.ml(-1)). However, addition of ammonium molybdate was found to cause a significant (P<0.05) dose-dependent decrease (at the doses 90, 170 and 500 microg.ml(-1)) in release of 17beta-estradiol by ovarian fragments in comparison to control. Also, addition of ammonium molybdate significantly (P<0.05) inhibited IGF-I release at all the doses (90-500 microg.ml(-1)) used in the study. Results suggest ammonium molybdate induced inhibition in the release of growth factor IGF-I and its dose-dependent effect on secretion of steroid hormone 17beta-estradiol but not progesterone. These data contribute to new insights regarding the mechanism of action of Mo on rat ovarian functions.

Interaction of vanadium (IV) solvates (L) with second-generation fluoroquinolone antibacterial drug ciprofloxacin: spectroscopic, structure, thermal analyses, kinetics and biological evaluation (L=An, DMF, Py and Et3N)

The preparation and characterization of the new solid complexes [VO(CIP)2L]SO4⋅nH2O, where L=aniline (An), dimethylformamide (DMF), pyridine (Py) and triethylamine (Et3N) in the reaction of ciprofloxacin (CIP) with VO(SO4)2·2H2O in ethanol. The isolated complexes have been characterized with their melting points, elemental analysis, IR spectroscopy, magnetic properties, conductance measurements, UV-Vis. and (1)H NMR spectroscopic methods and thermal analyses. The results supported the formation of the complexes and indicated that ciprofloxacin reacts as a bidentate ligand bound to the vanadium ion through the pyridone oxygen and one carboxylato oxygen. The activation energies, E(*); entropies, ΔS(*); enthalpies, ΔH(*); Gibbs free energies, ΔG(*), of the thermal decomposition reactions have been derived from thermo gravimetric (TGA) and differential thermo gravimetric (DTG) curves, using Coats-Redfern and Horowitz-Metzeger methods. The lowest energy model structure of each complex has been proposed by using the density functional theory (DFT) at the B3LYP/CEP-31G level of theory. The ligand and their metal complexes were also evaluated for their antibacterial activity against several bacterial species, such as Bacillus Subtilis (B. Subtilis), Staphylococcus aureus (S. aureus), Nesseria Gonorrhoeae (N. Gonorrhoeae), Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli (E. coli).

Copper(II) interacting with the non-steroidal antiinflammatory drug flufenamic acid: structure, antioxidant activity and binding to DNA and albumins

Copper(II) complexes with the non-steroidal antiinflammatory drug flufenamic acid (Hfluf) in the presence of N,N-dimethylformamide (DMF) or nitrogen donor heterocyclic ligands (2,2'-bipyridylamine (bipyam), 1,10-phenanthroline (phen), 2,2'-bipyridine (bipy) or pyridine (py)) have been synthesized and characterized. The crystal structures of [Cu2(fluf)4(DMF)2], 1, and [Cu(fluf)(bipyam)Cl], 2, have been determined by X-ray crystallography. Density functional theory (DFT) (CAM-B3LYP/LANL2DZ/6-31G**) was employed to determine the structure of complex 2 and its analogues (complexes [Cu(fluf)(phen)Cl], 3, [Cu(fluf)(bipy)Cl], 4 and [Cu(fluf)2(py)2], 5). Time-dependent DFT calculations of doublet-doublet transitions show that the lowest-energy band in the absorption spectrum of 2-5 has a mixed d-d/LMCT character. UV study of the interaction of the complexes with calf-thymus DNA (CT DNA) has shown that the complexes can bind to CT DNA with [Cu(fluf)(bipy)Cl] exhibiting the highest binding constant to CT DNA. The complexes can bind to CT DNA via intercalation as concluded by studying the cyclic voltammograms of the complexes in the presence of CT DNA solution and by DNA solution viscosity measurements. Competitive studies with ethidium bromide (EB) have shown that the complexes can displace the DNA-bound EB suggesting strong competition with EB. Flufenamic acid and its Cu(II) complexes exhibit good binding affinity to human or bovine serum albumin protein with high binding constant values. All compounds have been tested for their antioxidant and free radical scavenging activity as well as for their in vitro inhibitory activity against soybean lipoxygenase showing significant activity with [Cu(fluf)(phen)Cl] being the most active.

Structural features of mono- and tri-nuclear Zn(II) complexes with a non-steroidal anti-inflammatory drug as ligand

The interaction of Zn(II) with the non-steroidal anti-inflammatory drug tolfenamic acid leads to the formation of the structurally characterized trinuclear [Zn(3)(tolfenamato)(6)(CH(3)OH)(2)] complex. In the presence of the N,N'-donor heterocyclic ligands 1,10-phenanthroline and 2,2'-bipyridine at a range of ratios, the mononuclear Zn complexes of the general formulae [Zn(tolfenamato)(N,N'-donor)Cl] and [Zn(tolfenamato)(2)(N,N'-donor)] have been isolated and structurally characterized by X-ray crystallography. The deprotonated tolfenamato ligands are coordinated to the Zn(II) ion through carboxylato oxygen atoms. Tolfenamic acid and its complexes exhibit good binding propensity to human or bovine serum albumin protein having relatively high binding constant values.

Binding of Cu(II) complexes of oxicam NSAIDs to alternating AT and homopolymeric AT sequences: differential response to variation in backbone structure

Besides their principal functions as painkillers and anti-inflammatory agents, drugs belonging to the nonsteroidal anti-inflammatory drug (NSAID) group also have anticancer properties. Cu(II) complexes of these drugs enhance the anticancer effect. How they exert this effect is not clear. As a possible molecular mechanism, our group has already shown that the Cu(II) complexes of two oxicam NSAIDs with anticancer properties, viz. piroxicam and meloxicam, can directly bind to the DNA backbone. AT stretches are abundant in the eukaryotic genome. These stretches are more accessible to binding of different ligands, resulting in expression of different functions. AT stretches containing both alternating base pairs and homopolymeric bases in individual strands show subtle differences in backbone structures. It is therefore of interest to see how the Cu(II)-NSAID complexes respond to such differences in backbone structure. Binding studies of these complexes with alternating polydA-dT and homopolymeric polydA-polydT have been conducted using UV-vis absorption titration studies, UV melting studies and circular dichroism spectroscopy. Competitive binding with the standard intercalator ethidium bromide and the minor groove binder 4',6-diamidino-2-phenylindole was monitored using fluorescence to identify the possible binding mode. Our results show that Cu(II)-NSAID complexes are highly sensitive to the subtle differences in backbone structures of polydA-dT and polydA-polydT and respond to them by exhibiting different binding properties, such as binding constants, effect on duplex stability and binding modes. Both complexes have a similar binding mode with polydA-dT, which is intercalative, but for polydA-polydT, the results point to a mixed mode of binding.

Cobalt(II) complexes with non-steroidal anti-inflammatory drug tolfenamic acid: Structure and biological evaluation

Cobalt(II) complexes with the non-steroidal anti-inflammatory drug tolfenamic acid in the presence or absence of nitrogen-donor heterocyclic ligands (2,2'-bipyridine, 1,10-phenanthroline, 2,2'-bipyridylamine or pyridine) have been synthesized and characterized with physicochemical and spectroscopic techniques. The deprotonated tolfenamato ligands are coordinated to Co(II) ion through carboxylato oxygen atoms. The crystal structures of complexes [bis(2,2'-bipyridine) bis(methanol)bis(tolfenamato)cobalt(II)] 2 and [bis(2,2'-bipyridylamine)bis(tolfenamato)cobalt(II)] 4 have been determined by X-ray crystallography. UV studies of the interaction of the complexes with calf-thymus DNA (CT DNA) have shown that the complexes can bind to CT DNA and [bis(methanol)(1,10-phenanthroline)bis(tolfenamato)cobalt(II)] exhibits the highest binding constant to CT DNA. The cyclic voltammograms of the complexes recorded in DMSO solution and in the presence of CT DNA in 1/2 DMSO/buffer (containing 150 mM NaCl and 15 mM trisodium citrate at pH 7.0) solution have shown that they can bind to CT DNA by the intercalative binding mode which has also been verified by DNA solution viscosity measurements. Competitive study with ethidium bromide (EB) has shown that the complexes can displace the DNA-bound EB indicating that they bind to DNA in strong competition with EB. Tolfenamic acid and its cobalt(II) complexes exhibit good binding propensity to human or bovine serum albumin protein having relatively high binding constant values.

Biological evaluation of cobalt(II) complexes with non-steroidal anti-inflammatory drug naproxen

Cobalt(II) complexes with the non-steroidal anti-inflammatory drug naproxen in the presence or absence of nitrogen-donor heterocyclic ligands (pyridine, 2,2'-bipyridine or 1,10-phenanthroline) have been synthesized and characterized with physicochemical and spectroscopic techniques. The deprotonated naproxen acts as monodentate ligand coordinated to Co(II) ion through a carboxylato oxygen. The crystal structure of [bis(aqua)bis(naproxenato)bis(pyridine)cobalt(II)], 2 has been determined by X-ray crystallography. The EPR spectrum of complex 2 in frozen solution reveals that it retains its structure. UV study of the interaction of the complexes with calf-thymus DNA (CT DNA) has shown that the complexes can bind to CT DNA and [(2,2'-bipyridine)bis(methanol)bis(naproxenato)cobalt(II)] exhibits the highest binding constant to CT DNA. The cyclic voltammograms of the complexes recorded in DMSO solution and in the presence of CT DNA in 1/2 DMSO/buffer (containing 150 mM NaCl and 15 mM trisodium citrate at pH 7.0) solution have shown that they can bind to CT DNA by the intercalative binding mode which has also been verified by DNA solution viscosity measurements. Competitive study with ethidium bromide (EB) has shown that the complexes can displace the DNA-bound EB indicating that they bind to DNA in strong competition with EB. Naproxen and its cobalt(II) complexes exhibit good binding propensity to human or bovine serum albumin proteins having relatively high binding constant values. The antioxidant activity of the compounds has been evaluated indicating their high scavenging activity against hydroxyl free radicals and superoxide radicals.

Non-steroidal anti-inflammatory drug diflunisal interacting with Cu(II). Structure and biological features

Copper(II) complexes with the non-steroidal anti-inflammatory drug diflunisal in the presence of N,N-dimethylformamide or nitrogen donor heterocyclic ligands (pyridine, 1,10-phenanthroline, 2,2'-bipyridine or 2,2'-bipyridylamine) have been synthesized and characterized. The deprotonated diflunisal ligands are coordinated to Cu(II) ion through carboxylato oxygen atoms. The crystal structures of [tetrakis(diflunisal)bis(N,N-dimethylformamide)dicopper(II)] 1 and [bis(diflunisal)bis(pyridine)copper(II)], 2 have been determined by X-ray crystallography and are the first reported crystal structures of diflunisal complexes. UV study of the interaction of the complexes with calf-thymus DNA (CT DNA) suggests binding of the complexes to CT DNA with the dinuclear [tetrakis(diflunisal)bis(N,N-dimethylformamide)dicopper(II)] compound exhibiting the highest binding constant, K(b). Intercalative binding mode may also be concluded using cyclic voltammetry and solution viscosity measurements of the complexes in the presence of CT DNA. Competitive studies with ethidium bromide (EB) indicate that the complexes can displace the DNA-bound EB suggesting competition with EB. Diflunisal and its complexes exhibit good binding propensity to human or bovine serum albumin protein showing relatively high binding constant values.

Biological evaluation of non-steroidal anti-inflammatory drugs-cobalt(II) complexes

Cobalt(II) complexes with the non-steroidal anti-inflammatory drug mefenamic acid in the presence or absence of nitrogen donor heterocyclic ligands (2,2'-bipyridine, 1,10-phenanthroline or pyridine) have been synthesized and characterized with physicochemical and spectroscopic techniques. The experimental data suggest that mefenamic acid acts as deprotonated monodentate ligand coordinated to Co(II) ion through a carboxylato oxygen. The crystal structures of tetrakis(methanol)bis-(mefenamato)cobalt(II), 1 and (2,2'-bipyridine)bis(methanol)bis(mefenamato)cobalt(II), 2 have been determined by X-ray crystallography. The EPR spectra of complexes 1 and 2 in frozen solution reveal that they retain their structures. UV study of the interaction of the complexes with calf-thymus DNA (CT DNA) has shown that the complexes can bind to CT DNA and bis(methanol)bis(pyridine)bis-(mefenamato)cobalt(II) exhibits the highest binding constant. Competitive study with ethidium bromide (EB) has shown that the complexes can displace the DNA-bound EB indicating that they bind to DNA in strong competition with EB. The cyclic voltammograms of the complexes recorded in dmso solution and in the presence of CT DNA in 1 : 2 dmso : buffer (containing 150 mM NaCl and 15 mM trisodium citrate at pH 7.0) solution have shown that they can bind to CT DNA by the intercalative binding mode. Mefenamic acid and its cobalt(II) complexes exhibit good binding propensity to human or bovine serum albumin protein having relatively high binding constant values. The antioxidant activity of the compounds has been evaluated indicating their high scavenging activity against hydroxyl free radicals and superoxide radicals.

Non-steroidal antiinflammatory drug-copper(II) complexes: structure and biological perspectives

Copper(II) complexes with the non-steroidal antiinflammatory drug mefenamic acid in the presence of aqua or nitrogen donor heterocyclic ligands (2,2'-bipyridine, 1,10-phenanthroline, 2,2'-bipyridylamine or pyridine) have been synthesized and characterized. The crystal structures of [(2,2'-bipyridine)bis(mefenamato)copper(II)], 2, [(2,2'-bipyridylamine)bis(mefenamato)copper(II)], 4, and [bis(pyridine)bis(methanol)bis(mefenamato)copper(II)], 5, have been determined by X-ray crystallography. UV study of the interaction of the complexes with calf-thymus DNA (CT DNA) has shown that the complexes can bind to CT DNA and [bis(aqua)tetrakis(mefenamato)dicopper(II)] exhibits the highest binding constant to CT DNA. The cyclic voltammograms of the complexes in the presence of CT DNA solution have shown that the complexes can bind to CT DNA by the intercalative binding mode verified also by DNA solution viscosity measurements. Competitive studies with ethidium bromide (EB) indicate that the complexes can displace the DNA-bound EB suggesting strong competition with EB. Mefenamic acid and its complexes exhibit good binding propensity to human or bovine serum albumin protein having relatively high binding constant values. All the compounds have been tested for their antioxidant and free radical scavenging activity as well as for their in vitro inhibitory activity against soybean lipoxygenase showing significant activity.

In vitro assessment of molybdenum-induced secretory activity, proliferation and apoptosis of porcine ovarian granulosa cells

Molybdenum (Mo) is an essential trace element and it plays an important role in cell functions. The mechanism of the action of molybdenum in connection with growth factor IGF-I, proliferation-related peptide cyclin B1 and apoptosis-related peptide caspase-3 has not been examined previously in porcine ovarian granulosa cells. The general objective of this in vitro study was to examine the secretory activity of porcine ovarian granulosa cells after experimental Mo administration and to outline the potential intracellular mediators of its effects. Ovarian granulosa cells were incubated with ammonium molybdate for 18 hours: 1.0 mg/mL; 0.5 mg/mL; 0.33 mg/mL; 0.17 mg/mL and 0.09 mg/mL, while the control group received no Mo. The secretion of IGF-I was assessed by RIA and expression of cyclin B1 and caspase-3 by immunocytochemistry. IGF-I release was decreased by Mo addition at the doses 1.0 mg/mL and 0.5 mg/mL. The expression of cyclin B1 was stimulated by Mo addition at all doses ranging from 1.0-0.09 mg/mL. Caspase-3 expression was also stimulated after experimental Mo addition at the doses 1.0 and 0.5 mg/mL. These data contribute to new insights regarding the mechanism of action of Mo on porcine ovarian functions, secretory activity, proliferation and apoptosis of granulosa cells through hormonal and intracellular substances such as are cyclin B1 and caspase-3.

First ruthenium organometallic complex of antibacterial agent ofloxacin. Crystal structure and interactions with DNA

An organometallic ruthenium complex of quinolone antibacterial agent ofloxacin, [(η(6)-p-cymene)RuCl(O,O-oflo)]·2.8H(2)O (1·2.8H(2)O), was isolated, and its crystal structure was determined. In this "piano-stool" complex, quinolone is bidentately coordinated to the metal through the ring carbonyl and one of the carboxylic oxygen atoms. Interactions of the title complex with DNA were studied by spectroscopic methods [electronic, fluorescence, and circular dichroism (CD)] and atomic force microscopy (AFM). It was established that the electrostatic attraction between the ruthenium complex and DNA in a solution is important for binding because interactions were observed only in a solution with low ionic strengths. An induced-CD (ICD) signal was observed in a solution of DNA and the title complex, which proves interaction between ruthenium and macromolecules. Competitive binding between cisplatin and 1 to DNA revealed that cisplatin prevents binding of 1. Our experiments revealed that binding of the title complex to DNA occurs also if guanine N7 is protonated. AFM has shown that the title complex provokes DNA shrinkage. Preliminary biological tests have also been performed.

Interaction of copper(II) with the non-steroidal anti-inflammatory drugs naproxen and diclofenac: synthesis, structure, DNA- and albumin-binding

Copper(II) complexes with the non-steroidal anti-inflammatory drugs (NSAIDs) naproxen and diclofenac have been synthesized and characterized in the presence of nitrogen donor heterocyclic ligands (2,2'-bipyridine, 1,10-phenanthroline or pyridine). Naproxen and diclofenac act as deprotonated ligands coordinated to Cu(II) ion through carboxylato oxygens. The crystal structures of (2,2'-bipyridine)bis(naproxenato)copper(II), 1, (1,10-phenanthroline)bis(naproxenato)copper(II), 2 and bis(pyridine)bis(diclofenac)copper(II), 4 have been determined by X-ray crystallography. The UV study of the interaction of the complexes with calf-thymus DNA (CT DNA) has shown that the complexes can bind to CT DNA with (2,2'-bipyridine)bis(naproxenato)copper(II) exhibiting the highest binding constant to CT DNA. Competitive study with ethidium bromide (EB) indicates that the complexes can displace the DNA-bound EB suggesting strong competition with EB. The cyclic voltammograms of the complexes recorded in the presence of CT DNA have shown that the complexes can bind to CT DNA by the intercalative binding mode which has also been verified by DNA solution viscosity measurements. The NSAID ligands and their complexes exhibit good binding propensity to human or bovine serum albumin protein having relatively high binding constant values. The biological properties of the previously reported complexes [Cu(2)(naproxenato)(4)(H(2)O)(2)], [Cu(2)(diclofenac)(4)(H(2)O)(2)] and [Cu(naproxenato)(2)(pyridine)(2)(H(2)O)] have been also evaluated. The dinuclear complexes exhibit similar affinity for CT DNA as the 2,2'-bipyridine or 1,10-phenanthroline containing complexes. The pyridine containing complexes exhibit the lowest affinity for CT DNA and the lowest ability to displace EB from its EB-DNA complex.