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1.
Bull Exp Biol Med ; 177(2): 197-202, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39090470

RESUMO

Type 2 diabetes mellitus (T2DM) is accompanied by halogenative stress resulting from the excessive activation of neutrophils and neutrophilic myeloperoxidase (MPO) generating highly reactive hypochlorous acid (HOCl). HOCl in blood plasma modifies serum albumin (Cl-HSA). We studied the formation of neutrophil extracellular traps (NETs) in the whole blood and by isolated neutrophils under the action of Cl-HSA. It was found that Cl-HSA induces neutrophil priming and NETosis. MPO-containing as well as MPO-free NETs were found. These NETs with different composition can be a product of NETosis of one and the same neutrophil. NET formation in neutrophils with vacuolated cytoplasm was detected. In the presence of Cl-HSA, acceleration of NET degradation was observed. Accelerated NET degradation and neutrophil priming can be the factors contributing to the development of complications in T2DM.


Assuntos
Armadilhas Extracelulares , Ácido Hipocloroso , Neutrófilos , Peroxidase , Ácido Hipocloroso/metabolismo , Ácido Hipocloroso/farmacologia , Neutrófilos/metabolismo , Neutrófilos/efeitos dos fármacos , Armadilhas Extracelulares/metabolismo , Armadilhas Extracelulares/efeitos dos fármacos , Humanos , Peroxidase/metabolismo , Diabetes Mellitus Tipo 2/sangue , Albumina Sérica/metabolismo , Masculino
2.
Bull Exp Biol Med ; 175(2): 201-204, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37466859

RESUMO

We studied the properties of N6-chloroadenosine phosphates (ATP, ADP, and AMP chloramines) as compounds with potentially increased antiplatelet efficacy determined by their binding to the plasma membrane of platelets. Chloramine derivatives of ATP, ADP, and AMP do not differ in their optical absorption characteristics: their absorption spectra are in the range of 220-340 nm with a maximum at 264 nm. Chloramines of adenosine phosphates are characterized by high reactivity with respect to thiol compounds. In particular, the rate constants of the reaction of N6-chloroadenosine-5'-diphosphate with N-acetylcysteine, reduced glutathione, dithiothreitol, and cysteine reach 59,000, 250,000, 340,000, and 1,250,000 M-1×sec-1, respectively, and only 1.10±0.02 M-1×sec-1 with methionine. It has been found that N6-chloradenosine-5'-triphosphate is a strong inhibitor of platelet functions: it effectively suppresses ADP-induced cell aggregation (IC50 in the whole blood is 5 µM) and inhibits aggregation of preactivated platelets and induces dissociation of their aggregates.


Assuntos
Cloraminas , Agregação Plaquetária , Cloraminas/farmacologia , Cloraminas/química , Cloraminas/metabolismo , Compostos de Enxofre/metabolismo , Compostos de Enxofre/farmacologia , Plaquetas , Difosfato de Adenosina/farmacologia , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Enxofre/farmacologia , Monofosfato de Adenosina/metabolismo , Monofosfato de Adenosina/farmacologia
3.
Bull Exp Biol Med ; 176(2): 137-142, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38189871

RESUMO

NETosis, i.e., the formation of neutrophil extracellular traps (NET), and neutrophil autophagy are important elements in the pathogenesis and the development of complications of type 2 diabetes mellitus (T2DM). Therefore, the search of drugs that can regulate the level of NETosis and autophagy in T2DM is relevant. Here we studied an ex vivo NET formation and neutrophil death in whole blood from healthy subjects upon the addition of glucose up to a high concentration of 15 mM or/and the phorbol ester PMA (phorbol-12-myristate-13-acetate). Their individual and combined action caused neutrophil death and an increase in NET content. It can be hypothesized that this resulted from activation of NETosis and autophagy. It was also shown that this activation of NETosis and autophagy is completely prevented by daily intake of 1000 IU vitamin D3 for 14 days. Therefore, vitamin D3 supplementation can be considered as a preventive measure against the development of T2DM complications.


Assuntos
Diabetes Mellitus Tipo 2 , Armadilhas Extracelulares , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Neutrófilos , Glucose/farmacologia
4.
Bull Exp Biol Med ; 170(6): 748-751, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33893954

RESUMO

We analyzed functional status of blood leukocytes in diabetes mellitus and after addition of glucose in vitro. To this end, generation of ROS and reactive halogen species by monocytes and neutrophils from patients with diabetes mellitus and healthy donors was assayed using lucigenin- and luminol-dependent chemiluminescence after stimulation with phorbol 12-myristate 13-acetate or opsonized zymosan in vitro. Formation of neutrophil extracellular traps was evaluated in the blood after addition of glucose. In comparison with donors, leukocytes from patients with diabetes mellitus were primed and this effect can be modeled by addition of glucose to the blood in vitro. Addition of glucose to donor blood also triggered the formation of neutrophil extracellular traps.


Assuntos
Hiperglicemia/metabolismo , Leucócitos/metabolismo , Diabetes Mellitus/metabolismo , Armadilhas Extracelulares/metabolismo , Humanos , Medições Luminescentes , Neutrófilos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Zimosan/farmacologia
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 250: 119397, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33422875

RESUMO

Two adducts of Eu(III) tris-hexofluoroacetylacetonate with HMPA (OP(N(CH3)2)3, hexamethylphosphotriamide) and TPPO (OP(C6H5)3, triphenylphosphine oxide) were studied by optical spectroscopy and quantum chemistry (DFT/TD-DFT). The structure of the higher occupied molecular orbitals (MO) of the two adducts determines differences in the position of the excitation band maximum of hfac ligands. According to the calculation data, all excited states are caused by the transition to 3 vacant π4* MOs of hfac ligands. Optical spectra of absorption, excitation and luminescence are obtained and interpreted. The peculiarity of the HOMO-LUMO structure, the low value of the energy gap, and the broadened absorption region of hfac ligands compensate the low absorbance ability of the groups N(CH3)2 in a region of 220-360 nm for the adduct Eu(hfac)3(HMPA)2, reducing the luminescence intensity by only 5-10% relative to the adduct of the Eu(III) complex with TPPO ligands.

6.
Bull Exp Biol Med ; 168(1): 48-51, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31745682

RESUMO

We studied antidepressant and antiparkinsonian properties of N-(5-hydroxynicotinoyl)-Lglutamic acid calcium salt (Ampasse) in rodents. It was found that Ampasse in a dose of 30 mg/kg exhibited antidepressant activity in the forced swimming test in mice and in a dose of 0.1 mg/kg maximally alleviates the symptoms of parkinsonian syndrome induced by systemic administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine in C57Bl/6 mice, and haloperidol-induced catalepsy in rats.


Assuntos
Antidepressivos/uso terapêutico , Cálcio/química , Depressão/tratamento farmacológico , Ácido Glutâmico/química , Ácido Glutâmico/uso terapêutico , Transtornos Parkinsonianos/tratamento farmacológico , Animais , Catalepsia/induzido quimicamente , Haloperidol/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
7.
Bull Exp Biol Med ; 167(6): 732-734, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31655993

RESUMO

Generation of ROS (including free radicals) in rat platelets during physical exercises of different intensities was evaluated by the chemiluminescent method. The acute or chronic submaximal exercises increased the platelet chemiluminescence by 2.5-3.0 times. In the control, platelet activation with physiological aggregant ADP enhanced their chemiluminescence by 7.5 times. Addition of ADP to platelets isolated from animals subjected to exercise of any intensity increased chemiluminescence by 4-5 times. In a trained organism, functional reserve of the platelets is preserved during long-term physical exercise of any intensity, but is exhausted after acute physical exercise. Thus, intensive physical exercises enhanced the hemostatic potential of the blood, which is associated with the risk of thrombohemorrhagic complications, especially in acute or submaximal long-term exercises.


Assuntos
Plaquetas/fisiologia , Luminescência , Condicionamento Físico Animal/fisiologia , Animais , Animais não Endogâmicos , Radicais Livres/metabolismo , Masculino , Condicionamento Físico Animal/métodos , Esforço Físico/fisiologia , Ativação Plaquetária/fisiologia , Ratos , Espécies Reativas de Oxigênio/metabolismo , Natação/fisiologia
8.
J Hazard Mater ; 369: 25-30, 2019 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-30763796

RESUMO

The work presents a novel method for fabrication of the high-quality ionizing radiation source (IRS), which is promising to replace unsafe commercial products based on 137CsCl prohibited by IAEA. Spark plasma sintering (SPS) technique has been applied to produce dense ceramic and glass-ceramic matrixes from Cs-containing (˜13.5 wt.%) zeolite yielding in non-dispersible cores sealed in the container of radiation-resistant steel (J93503, US standard). One-stage SPS regimes to provide high-quality product have been optimized: sintering temperature <1000 °C, heating and holging duration 13 and 5 min, respectively, pressure 24.5 MPa. XRD, SEM, EDX, BET, XFS and solid-state MAS NMR 133Cs methods prove exceptional physico-chemical and mechanical characteristics of the obtained materials, namely: density 99.8% from theoretical, compressive strength ˜477 MPa, leaching rate 10-4-10-6 g cm-2 day-1. Results of the investigation can be promising for fabrication of the IRS cores on a large scale as done for similar Russian products RSL, IGI-C, M37C, GID-C.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 213: 176-183, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30685556

RESUMO

Adducts of tris-nitrates of rare-earth elements Ce(III), Nd(III), Eu(III), and Er(III) with two molecules of 1,10-phenanthroline with formula Ln(NO3)3(Phen)2 are studied by X-ray photoelectron spectroscopy (XPS) and quantum chemistry (DFT/TDDFT). The geometric structure for DFT modeling is build using X-ray diffraction data. To analyze the composition and differences of the electronic structure in the series under study, XPS spectra were obtained for which interpretation was performed using calculated data. It has been shown that the molecule of Phen, when attached to the complexes of nitrates, is polarized, leads to an increase in absorption in the visible region and reduces the energy gap between HOMO and LUMO. Experimental absorption spectra were obtained, described and interpreted using TDDFT simulation. The transitions in adducts from π to π * MO in Phen ligands determine the main absorption band. The reasons for the absence of luminescence in adducts with ions Ce(III), Nd(III), and Er(III) are revealed by the example of the correlation diagram of singlet and triplet levels. A possible origin of coloring of adducts is determined using TDDFT.

10.
Bull Exp Biol Med ; 165(1): 27-30, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29797131

RESUMO

The study examined the effect of calcium salt of N-(5-hydroxynicotinoil)-L-glutamic acid (Ampasse preparation) on neuronal activity in hippocampal CA1 area evoked by stimulation of Schaffer collaterals at a rate of 1 Hz (30 impulses during 30 sec) in the surviving hippocampal slices of Wistar rats. The records of 1st and 30th orthodromic population spikes showed that Ampasse in concentrations of 500 µM, 1, 2, and 10 mM facilitated the synaptic transmission in Schaffer collaterals - hippocampal CA1 pyramidal neurons axis; the maximum effect was observed at 2 mM Ampasse. When used in a concentration of 10 mM, Ampasse provoked epileptiform activity, which could be prevented by MK-801, a specific noncompetitive antagonist of the NMDA-receptor complex.


Assuntos
Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/metabolismo , Ácido Glutâmico/farmacologia , Células Piramidais/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Animais , Ácido Glutâmico/química , Masculino , Ratos , Ratos Wistar , Receptores de N-Metil-D-Aspartato/metabolismo
11.
Eksp Klin Gastroenterol ; (6): 75-9, 2016.
Artigo em Russo | MEDLINE | ID: mdl-30280810

RESUMO

In a review article analyzes and summarizes information on the current pathogenesis of bile peritonitis. The role of endothelial dysfunction markers, as a factor in the development of ischemic disorders interstitial circulation contributes to the elucidation of the molecular mechanisms of the pathogenesis of peritonitis, including bile peritonitis. This review is an attempt to synthesize and analyze accumulated information on the pathogenetic aspects of the development of peritonitis, which will optimize the diagnosis, the development of methods of prevention and treatment. This study dysfunction of vascular endothelium, will provide additional information relevant to the prediction of the adaptation of the organism in the syndrome of endogenous intoxication.


Assuntos
Endotélio Vascular , Enteropatias , Mucosa Intestinal , Intestinos , Isquemia , Peritonite , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Humanos , Enteropatias/etiologia , Enteropatias/metabolismo , Enteropatias/patologia , Enteropatias/fisiopatologia , Mucosa Intestinal/metabolismo , Intestinos/irrigação sanguínea , Intestinos/patologia , Intestinos/fisiopatologia , Isquemia/etiologia , Isquemia/metabolismo , Isquemia/patologia , Isquemia/fisiopatologia , Peritonite/complicações , Peritonite/metabolismo , Peritonite/patologia , Peritonite/fisiopatologia
12.
Bull Exp Biol Med ; 159(5): 623-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26459479

RESUMO

We studied the effects of tactivin and splenic polypeptides on learning and memory of thymectomized animals. In 3-week rats, thymectomy blocked active avoidance conditioning. Injections of tactivin (0.5 mg/kg) during 1 month after surgery restored learning capacity; splenic polypeptides were ineffective.


Assuntos
Aprendizagem da Esquiva/efeitos dos fármacos , Memória/efeitos dos fármacos , Nootrópicos/farmacologia , Peptídeos/farmacologia , Timectomia , Extratos do Timo/farmacologia , Timo/química , Animais , Aprendizagem da Esquiva/fisiologia , Condicionamento Clássico/fisiologia , Memória/fisiologia , Nootrópicos/isolamento & purificação , Especificidade de Órgãos , Peptídeos/isolamento & purificação , Ratos , Ratos Wistar , Baço/química , Extratos do Timo/isolamento & purificação , Timo/fisiologia , Timo/cirurgia
14.
Bull Exp Biol Med ; 159(1): 107-10, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26028234

RESUMO

Express-test by the method of coherent fluctuation nephelometry for urine contamination was carried out on two prototype instruments with standard polystyrene photometric cuvettes. We analyzed 209 and 119 urine samples. Due to high sensitivity of the method, up to 50% negative samples were detected within 10 min by initial opacity and 90% negative samples were detected during 3.5 h by registration of the bacterial growth curves.


Assuntos
Bacteriúria/diagnóstico , Nefelometria e Turbidimetria/métodos , Urinálise/métodos , Humanos
15.
Vestn Ross Akad Med Nauk ; (1): 113-7, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26027280

RESUMO

OBJECTIVE: Our aim was to investigate the influence of thymic polypeptides on pain sensitivity and to analyze a possible role of the opioid system in the implementation of the analgesia caused by immobilization stress. METHODS: The study was performed on male Wistar rats at the Moscow state University named after M. V. Lomonosov. We studied effects of thymus peptides: thymuline (0.15 mg/kg), fraction 5 thymosin (0.25 microgram/kg) and cattle thymus extracted product (CTEP) (0.5 mg/kg) on pain sensitivity in rats using test "tail flick" without stress, with acute (3 h) and sub acute (12 h) immobilization stress. The comparison groups were animals treated with saline and spleen polypeptides. RESULTS: It is shown that preparations of thymus increase the threshold of pain sensitivity in the intact animals. Immobilization stress duration 3 and 12 h in thymus peptides treated rats caused a less pronounced increase in pain threshold than in the control groups (immobilization stress 3 h: CTEP--p = 0.025, thymuline--p = 0.022, fraction 5 thymosin--p = 0.033; immobilization stress 12 h: CTEP--p = 0.034, thymuline--p = 0.027, fraction 5 thymosin--p = 0.036). The opioid receptor blocker naloxone (1 mg/kg) did not completely block the stress-induced analgesia, indicating the presence of both opioid and non -opioid components in this state. In thymus peptides treated rats, opioid component was less pronounced than in the control groups (CTEP--p = 0.031, thymuline--p = 0.026, fraction 5 thymosin--p = 0.029). CONCLUSION: Pre-activation of the opioid system by the thymus polypeptides leads to an increase in the share of non-opioid component of the stress-induced analgesia and prevents the depletion of the opioid system in immobilization stress.


Assuntos
Naloxona/farmacologia , Dor , Restrição Física/efeitos adversos , Fator Tímico Circulante , Timosina , Timo/metabolismo , Analgesia/métodos , Animais , Bovinos , Masculino , Modelos Animais , Antagonistas de Entorpecentes/farmacologia , Dor/diagnóstico , Dor/tratamento farmacológico , Dor/etiologia , Dor/metabolismo , Dor/fisiopatologia , Manejo da Dor , Ratos , Ratos Wistar , Receptores Opioides/metabolismo , Fator Tímico Circulante/metabolismo , Fator Tímico Circulante/farmacologia , Timosina/metabolismo , Timosina/farmacologia , Extratos do Timo/metabolismo , Extratos do Timo/farmacologia
16.
Bull Exp Biol Med ; 158(6): 753-5, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25896593

RESUMO

Experiments on Wistar rats showed that thymic peptides produce a stress-protective effect that manifested in prevention of functional impairment of conditioned active avoidance response and a decrease in generalized motor activity typical of higher nervous activity failure. We concluded that thymic peptides significantly modulate integrative functions of the brain and produce a stress-protective effect.


Assuntos
Aprendizagem da Esquiva/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Peptídeos/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Animais , Ratos , Ratos Wistar
17.
Vestn Ross Akad Med Nauk ; (6): 727-33, 2015.
Artigo em Russo | MEDLINE | ID: mdl-27093801

RESUMO

The review presents data on mutual influence of nervous system and thymus, realized through the neuroendocrine-immune interactions. The pres- ence of adrenergic and peptidergic nerves in thymus creates conditions for implementation of the effect of neuropeptides secreted by them. These neuropeptides induce activation of thymus cells receptors and influence on the main processes in thymus, including T-lymphocyte maturation, cytokine and hormones production. In turn, thymuspeptides and/or cytokines, controlled by them, enter the brain and exert influence on neuro- nalfunction, which creates the basis for changes of behavior and homeostasis maintenance in response to infection. Ageing and some infectious, autoimmune, neurodegenerative and cancer diseases are accompanied by distortion of interactions between thymus and central nervous system. Mechanisms of signaling pathways, which determine these interactions, are not revealed yet, and their understanding will promote the development of effective therapeutic strategies.


Assuntos
Sistema Nervoso Central , Citocinas/metabolismo , Neuropeptídeos/metabolismo , Sistemas Neurossecretores , Timo , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/fisiopatologia , Homeostase , Humanos , Neuroimunomodulação , Sistemas Neurossecretores/metabolismo , Sistemas Neurossecretores/fisiopatologia , Transdução de Sinais , Timo/metabolismo , Timo/fisiopatologia
18.
J Thromb Haemost ; 13(4): 570-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25393591

RESUMO

BACKGROUND: Fibrinogen has been intensively studied with transmission electron microscopy and x-ray diffraction. But until now, a complete 3D structure of the molecule has not yet been available because the two highly flexible αC regions could not be resolved in fibrinogen crystals. This study was aimed at determining whether the αC regions can be visualized by high-resolution atomic force microscopy. METHODS: Atomic force microscopy with super high resolution was used to image single molecules of fibrinogen and fibrin associates. The key approach was to use a graphite surface modified with the monolayer of amphiphilic carbohydrate-glycine molecules and unique supersharp cantilevers with 1 nm tip diameter. RESULTS: Fibrinogen αC regions were visualized along with the complete domain structure of the protein. In almost all molecules at pH 7.4 the D domain regions had one or two protrusions of average height 0.4 ± 0.1 nm and length 21 ± 6 nm. The complex, formed between thrombin and fibrinogen, was also visualized. Images of growing fibrin fibers with clearly visible αC regions have been obtained. CONCLUSIONS: Fibrin αC regions were visible in protofibrils and large fibers; αC regions intertwined near a branchpoint and looked like a zipper. These results support the idea that αC regions are involved in the thickening of fibrin fibers. In addition, new details were revealed about the behavior of individual fibrin molecules during formation of the fibrin network. Under the diluted condition, the positioning of the αC regions could suggest their involvement in long-range interactions between fibrin but not fibrinogen molecules.


Assuntos
Coagulação Sanguínea , Fibrina/ultraestrutura , Fibrinogênio/ultraestrutura , Microscopia de Força Atômica , Fragmentos de Peptídeos/ultraestrutura , Absorção Fisico-Química , Fibrina/metabolismo , Fibrinogênio/metabolismo , Grafite/química , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Fragmentos de Peptídeos/metabolismo , Agregados Proteicos , Estrutura Terciária de Proteína , Relação Estrutura-Atividade , Propriedades de Superfície
20.
Bull Exp Biol Med ; 157(3): 371-4, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25070165

RESUMO

Subfraction with a molecular weight >250 kDa isolated from porcine skin and inhibiting the proliferation of A431 human carcinoma epidermoid cells was purified by DEAE 32 anion exchange chromatography with NaCl concentration step-gradient. The effects of the initial subfraction and fractions obtained by separation in DEAE 32 on the proliferation of A431 human carcinoma epidermoid cells were studied in vitro in two tests (MTT and fluorescent test). The more sensitive fluorescent test showed the highest inhibitory activity of fraction No. 2 released from the column at 0.15 M NaCl. One major protein component and a series of minor protein components were detected in this fraction by vertical PAAG-SDS electrophoresis.


Assuntos
Antineoplásicos/farmacologia , Pele/química , Extratos de Tecidos/farmacologia , Animais , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromatografia por Troca Iônica , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Peso Molecular , Sus scrofa , Extratos de Tecidos/isolamento & purificação
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