RESUMO
A large series of 2-arylchromen-4-ones containing from 1 to 3 fluorine atoms or a trifluoromethyl group in the structure was synthesized by condensation of fluorinated 2-hydroxyacetophenones with benzaldehydes in an alkaline medium and subsequent oxidative cyclization of the resulting 2'-hydroxychalcones by action of I2 in DMSO. The cytotoxicity of the obtained compounds was studied in glioblastoma cell line, SNB19, and in a monkey-derived normal kidney epithelium cell line, Vero. In addition, antiglycation activity of the obtained compounds was evaluated. The inhibitory activity of some fluorinated 2-arylchromen-4-ones against acetylcholinesterase, butyrylcholinesterase and carboxylesterase as well their primary antioxidant activity in ABTS and FRAP tests were investigated. Screening of the synthesized compounds for their inhibitory activity against influenza A virus A/Puerto Rico/8/34 (H1N1) in the MDCK cell culture revealed that fluorinated compounds 32, 31 and 39 showed manifest antiviral effects (with IS = 57, 38 and 25 correspondingly) that makes this series of new biologically attractive fluorinated heterocycles promising for further development and in-depth study.
RESUMO
Phosphorylated adenosine derivatives are important biological molecules with diverse biological functions connected with the energetic balance of the cell, biosynthesis of cell components and regulation of protein activity. Measurement of these compounds provides information about the cell signalling in the body as well as the quantity of microorganisms in the environment. Surface-enhanced Raman spectroscopy (SERS) is an optical method that provides a unique spectrum of a substance at low concentrations. Specificity and limit of detection of SERS-based sensors can be increased drastically using nucleic acid aptamers and Raman-active dyes, respectively. Here we describe an adenosine monophosphate (AMP) biosensor based on AMP-dependent interaction between the well-known DNA aptamer for AMP and a novel Raman-active dye. The SERS intensity of novel Black Hole Quencher-2 (BHQ-2) derivatives was shown to be proportional to the charge of the molecule indicating electrostatic interactions with negatively charged colloidal silver nanoparticles. The novel derivative of BHQ-2 with two amine groups, BHQ-2-(NH2)2, binds an unpaired guanine stacked between guanine-guanine and guanine-adenine mismatches in DNA aptamer-AMP complex with KD = 26 nM as shown by 1H nuclear magnetic resonance, molecular docking and biolayer interferometry. The aptamer is pre-structured by AMP being folded in the conformation favorable for the interaction with BHQ-2-(NH2)2. This specific mechanism of the interaction allows designing of a SERS-based aptasensor with a limit of detection being as low as 3.4 nM of AMP and the dynamic range of nearly 5 orders - from 3.4 nM to 200 µM. The results illustrate a new approach to biosensors where DNA-interacting ligands act as external responsive elements providing an analyte-dependent SERS signal.
Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Monofosfato de Adenosina , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Ouro/química , Guanina , Nanopartículas Metálicas/química , Simulação de Acoplamento Molecular , Prata/química , Análise Espectral Raman/métodosRESUMO
4-Arylhydrazinylidene-5-(polyfluoroalkyl)pyrazol-3-ones (4-AHPs) were found to be obtained by the regiospecific cyclization of 2-arylhydrazinylidene-3-(polyfluoroalkyl)-3-oxoesters with hydrazines, by the azo coupling of 4-nonsubstituted pyrazol-5-oles with aryldiazonium chlorides or by the firstly discovered acid-promoted self-condensation of 2-arylhydrazinylidene-3-oxoesters. All the 4-AHPs had an acceptable ADME profile. Varying the substituents in 4-AHPs promoted the switching or combining of their biological activity. The polyfluoroalkyl residue in 4-AHPs led to the appearance of an anticarboxylesterase action in the micromolar range. An NH-fragment and/or methyl group instead of the polyfluoroalkyl one in the 4-AHPs promoted antioxidant properties in the ABTS, FRAP and ORAC tests, as well as anti-cancer activity against HeLa that was at the Doxorubicin level coupled with lower cytotoxicity against normal human fibroblasts. Some Ph-N-substituted 4-AHPs could inhibit the growth of N. gonorrhoeae bacteria at MIC 0.9 µg/mL. The possibility of using 4-AHPs for cell visualization was shown. Most of the 4-AHPs exhibited a pronounced analgesic effect in a hot plate test in vivo at and above the diclofenac and metamizole levels except for the ones with two chlorine atoms in the aryl group. The methylsulfonyl residue was proved to raise the anti-inflammatory effect also. A mechanism of the antinociceptive action of the 4-AHPs through blocking the TRPV1 receptor was proposed and confirmed using in vitro experiment and molecular docking.
Assuntos
Antioxidantes , Diclofenaco , Humanos , Simulação de Acoplamento Molecular , Antioxidantes/química , Preparações FarmacêuticasRESUMO
Syringomyelia (SM) with Chiari malformation is a rare disease with an unpredictable course. Surgery and other interventions help reduce the severity of symptoms, but over 50% patients require re-operation. Auto-resolution is rare in this type of SM, and most cases progress to complications, which may amount to a great burden. The patient of SM with Arnold-Chiari malformation type 1 in a 54-year-old Russian woman who was treated with individualized classical homeopathy for over eight years with remarkable improvement in the clinical signs and symptoms of the condition and comorbidities. On MRI, the syrinx completely resolved, which further confirmed the benefit of this therapy. This case of SM with Arnold-Chiari malformation type 1 seemed to benefit from individualized classical homeopathy. Scientific investigation into an individualized classical homeopathic approach towards SM is necessary to establish its relevance in this condition.
RESUMO
4-Nitroso-3-trifluoromethyl-5-alkyl[(het)aryl]pyrazoles were synthesized via one-pot nitrosation of 1,3-diketones or their lithium salts followed by treatment of hydrazines. Reduction of nitroso-derivatives made it possible to obtain 4-amino-3-trifluoromethylpyrazoles chlorides. According to computer-aided calculations, all synthesized compounds are expected to have acceptable ADME profile for drug design. Tuberculostatic, antibacterial, antimycotic, antioxidant and cytotoxic activities of the compounds were evaluated in vitro, while their analgesic and anti-inflammatory action was tested in vivo along with acute toxicity studies. N-Unsubstituted 4-nitrosopyrazoles were the most effective tuberculostatics (MIC to 0.36 µg/ml) and antibacterial agents against Streptococcus pyogenes (MIC to 7.8 µg/ml), Staphylococcus aureus,S. aureus MRSA and Neisseria gonorrhoeae (MIC to 15.6 µg/ml). 4-Nitroso-1-methyl-5-phenylpyrazole had the pronounced antimycotic action against a wide range of fungi (Trichophytonrubrum, T. tonsurans, T. violaceum, T. interdigitale, Epidermophytonfloccosum, Microsporumcanis with MIC 0.38-12.5 µg/ml). N-Unsubstituted 4-aminopyrazoles shown high radical-scavenging activity in ABTS test, ORAC/AAPH and oxidative erythrocyte hemolysis assays. 1-Methyl-5-phenyl-3-trifluoromethylpyrazol-4-aminium chloride revealed potential anticancer activity against HeLa cells (SI > 1351). The pronounced analgesic activity was found for 4-nitroso- and 4-aminopyrazoles having phenyl fragment at the position 5 in "hot plate" test. The most of the obtained pyrazoles had a moderate acute toxicity.
Assuntos
Compostos Nitrosos/farmacologia , Pirazóis/farmacologia , Animais , Bactérias/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Epidermophyton/efeitos dos fármacos , Células HeLa , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Compostos Nitrosos/síntese química , Compostos Nitrosos/farmacocinética , Compostos Nitrosos/toxicidade , Pirazóis/síntese química , Pirazóis/farmacocinética , Pirazóis/toxicidade , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Trichophyton/efeitos dos fármacosRESUMO
Pressure overload is associated with cardiac hypertrophy and electrical remodeling. Here, we investigate the effects of the antioxidant N-acetylcysteine (NAC) on the cellular cardiac electrophysiology of female Sprague-Dawley rats with ascending aortic stenosis (AS). Rats were treated with NAC (1 g/kg body weight) or control solution 1 week before the intervention and in the week following AS or sham operation. Seven days after the operation, blood pressure and left ventricular pressure were measured before the heart was excised. Single cells were isolated from epicardial and endocardial layers of the left ventricular free wall and investigated using the whole-cell patch-clamp technique. Systolic blood pressure and left ventricular peak pressure were not significantly altered in the NAC group. NAC reduced the increase (p < 0.001) in the relative left ventricular weight (p < 0.05) as well as the increase (p < 0.001) in cell capacitance in epicardial (p < 0.05), but not in endocardial myocytes of AS animals. The L-type Ca(2+) current (I (CaL)) was significantly increased by AS in epicardial (+19 % at 0 mV, p < 0.01) but not in endocardial myocytes. NAC completely prevented this increase in I (CaL) (p < 0.01). The current density of the transient outward K(+) current (I (to)) was not affected by AS or NAC. Action potential duration to 90 % repolarization was significantly prolonged in epicardial (p < 0.01) as well as in endocardial (p < 0.001) cells of AS animals. NAC prevented the AP prolongation in epicardial myocytes only (p < 0.05). We conclude that reducing oxidative stress in pressure overload can prevent electrical remodeling and ameliorate hypertrophy in epicardial but not in endocardial myocytes.
Assuntos
Acetilcisteína/uso terapêutico , Antioxidantes/uso terapêutico , Estenose da Valva Aórtica/tratamento farmacológico , Cardiomegalia/tratamento farmacológico , Endocárdio/patologia , Miócitos Cardíacos/patologia , Remodelação Ventricular , Potenciais de Ação/efeitos dos fármacos , Animais , Aorta , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/patologia , Cálcio/metabolismo , Canais de Cálcio Tipo L/fisiologia , Feminino , Hemodinâmica/efeitos dos fármacos , Ratos , Ratos Sprague-DawleyRESUMO
Mineralocorticoid receptor (MR) activation modulates cardiac L-type Ca(2+) current (I (CaL)) and transient outward K(+) current (I (to)). The exact circumstances of MR activation, however, remain elusive. Here, we investigate the influence of corticosteroids on MR-mediated changes in cellular electrophysiology. In vitro incubation of adult rat ventricular myocytes with the MR agonist aldosterone (100 nM, 24 h) increased I (CaL) density by 34% (n = 16; p < 0.01). This effect was abrogated by co-incubation with the MR antagonist spironolactone (10 muM). To investigate whether an increase in serum aldosterone concentration is sufficient for an increase in I (CaL) in vivo, rats were subjected to low Na(+) diet (LSD, 0.013% Na(+)) for 28 days. This increased serum aldosterone concentration from 0.19 +/- 0.04 nM (n = 6) in control animals (0.3% Na(+), CSD) to 16.1 +/- 2.1 nM (n = 6; p < 0.0001). Strikingly, I (CaL) density was similar in both CSD and LSD rats (-12.9 +/- 0.9 pA pF(-1), n = 18 and -13.7 +/- 1.1 pA pF(-1), n = 16, respectively), as was I (to) density. In vitro, the glucocorticoid corticosterone (1 microM) also increased I (CaL) and this effect was blocked by spironolactone (10 microM). Co-incubation with corticosterone (1 microM, the normal serum concentration) and aldosterone (100 nM, mimicking low Na(+) intake) did not further increase I (CaL) compared to corticosterone alone. Moreover, co-incubation of myocytes with N-acetylcysteine (10 mM) prevented the aldosterone (100 nM) or corticosterone (1 microM)-induced increase in I (CaL). In conclusion, an increase in serum aldosterone concentration in response to LSD is not sufficient for an increase in I (CaL) density in cardiomyocytes in vivo. This is supported in vitro by the absence of an effect of aldosterone on I (CaL) in the presence of a physiological concentration of corticosterone. Moreover, the cellular redox state may modulate MR activation.