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1.
Chem Biol Interact ; 220: 200-7, 2014 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-25016077

RESUMO

UNLABELLED: The ability to intercalate between DNA strands determines the cytotoxic activity of numerous anticancer drugs. Strikingly, intercalating activity was also reported for some compounds considered to be antimutagenic. The aim of this study was to determine the mode of interaction of DNA with the antimutagenic and DNA repair-stimulating dihydropyridine (DHP) AV-153. DNA and AV-153 interactions were studied by means of UV/VIS spectroscopy, fluorimetry and infrared spectroscopy. Compound AV-153 is a 1,4 dihydropyridine with ethoxycarbonyl groups in positions 3 and 5. Computer modeling of AV-153 and DNA interactions suggested an ability of the compound to dock between DNA strands at a single strand break site in the vicinity of two pyrimidines, which was confirmed in the present study. AV-153 evidently interacted with DNA, as addition of DNA to AV-153 solutions resulted in pronounced hyperchromic and bathochromic effects on the spectra. Base modification in a plasmid by peroxynitrite only minimally changed binding affinity of the compound; however, induction of single-strand breaks using Fenton's reaction greatly increased binding affinity. The affinity did not change when the ionic strength of the solution was changed from 5 to 150 mM NaCl, although it increased somewhat at 300 mM. Neither was it influenced by temperature changes from 25 to 40°C, however, it decreased when the pH of the solution was changed from 7.4 to 4.7. AV-153 competed with EBr for intercalation sites in DNA: 116 mM of the compound caused a two-fold decrease in fluorescence intensity. FT-IR spectral data analyses indicated formation of complexes between DNA and AV-153. The second derivative spectra analyses indicated interaction of AV-153 with guanine, cytosine and thymine bases, but no interaction with adenine was detected. CONCLUSIONS: The antimutagenic substance AV-153 appears to intercalate between the DNA strands at the site of a DNA nick in the vicinity of two pyrimidines.


Assuntos
Antimutagênicos/química , DNA/química , Di-Hidropiridinas/química , Niacina/análogos & derivados , Animais , Antimutagênicos/metabolismo , Sítios de Ligação , DNA/metabolismo , Reparo do DNA/efeitos dos fármacos , Di-Hidropiridinas/metabolismo , Di-Hidropiridinas/farmacologia , Fígado/química , Estrutura Molecular , Niacina/química , Niacina/metabolismo , Niacina/farmacologia , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Biochemistry (Mosc) ; 77(6): 679-88, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22817469

RESUMO

The tightly bound proteins (TBPs), a protein group that remains attached to DNA either covalently or noncovalently after deproteinization, have been found in numerous eukaryotic species. Some TBPs isolated from mammalian and yeast cells possess phosphatase or kinase activity. The aim of this study was to characterize further TBPs in barley (Hordeum vulgare) cells. The spectra of TBPs varied in different organs of barley shoots (first leaves, coleoptile, and roots) and at different developmental stages of the plant. Some barley TBPs manifested phosphatase, probably Ser/Thr or dual Ser/Thr/Tyr activity. MALDI-TOF mass spectrometry of barley TBPs identified several proteins involved in chromatin rearrangement and regulation processes, including transcription factors, serpins, protein phosphatases and protein kinases, RNA helicases, and DNA topoisomerase II.


Assuntos
DNA de Plantas/metabolismo , Proteínas de Ligação a DNA/metabolismo , Hordeum/crescimento & desenvolvimento , Monoéster Fosfórico Hidrolases/metabolismo , Proteínas de Plantas/metabolismo , Montagem e Desmontagem da Cromatina/fisiologia , Cotilédone/enzimologia , Cotilédone/genética , Cotilédone/crescimento & desenvolvimento , DNA Topoisomerases Tipo II/análise , Hordeum/enzimologia , Hordeum/genética , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/análise , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Proteínas Quinases/análise , RNA Helicases/análise , Serpinas/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
3.
Gene ; 492(1): 54-64, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22001404

RESUMO

Tightly bound to DNA proteins (TBPs) are a protein group that remains attached to DNA after its deproteinization by phenol, chloroform or salting-out. TBP are bound to DNA with covalent phosphotriester or non-covalent ion and hydrogen bonds. They appear to be a vast protein group involved in numerous intranuclear processes. The TBPs fraction co-purified with DNA deproteinized by mild procedures is extremely heterogeneous, tissue and species-specific. The protein fraction co-purified with DNA after harsh deproteinization procedures appears to be formed from few polypeptides common to different species and tissues. Interaction sites between DNA and TBPs depend on the physiological status of the cell. The binding sites of TBPs to DNA do not co-localize with the nuclear matrix attachment regions. We hypothesize that TBPs form a universal substrate for intranuclear processes.


Assuntos
Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Animais , Proteínas de Ligação a DNA/química , Modelos Biológicos , Especificidade de Órgãos , Monoéster Fosfórico Hidrolases/metabolismo , Serpinas/metabolismo , Especificidade da Espécie , Transcrição Gênica
4.
Exp Oncol ; 33(3): 121-5, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21956462

RESUMO

UNLABELLED: Proteins tightly bound to DNA (TBP) comprise a group of proteins that remain bound to DNA even after harsh deproteinization procedures. The amount of these proteins is 20-100 µg for mg of DNA depending on eukaryotic source. This experimental paper examines the possibility to use some TBP for clinical biomarker discovery, e.g. for identification of prognostic and diagnostic cancer markers. The main aim of this study was to designate differences between tightly DNA binding protein patterns extracted from rat liver and rat experimental hepatomas (Zajdela ascites hepatoma and hepatoma G-27) and to evaluate possibility that some of these proteins may be used as biomarkers for cell cancer transformation. METHODS: We used proteomics aproach as a tool for comparison of pattern of TBP from rat experimental hepatomas and normal liver cells. Combination of 2DE fractionation with mass spectrometry (MALDI TOF-MS) suitable for parallel profiling of complex TBP mixtures. RESULTS: Intriguingly 2DE protein maps of TBP from rat liver and rat experimental hepatomas (Zajdela acites hepatoma and hepatoma G-27) were quite different. We identified 9 proteins, some of them shared in all TBP patterns. Among identified tightly bound to DNA proteins there were three proteins considered as nuclear matrix proteins (lamin B1, scaffold attachment factor B1, heterogeneous nuclear ribonucleoprotein). Also we identified DNA repair protein RAD50, coiled-coil domain-containing protein 41, structural maintenance of chromosomes protein1A and some ATP -dependent RNA helicases indicating that TBP are of interest with respect to their potential involvement in the topological organization and/ or function of genomic DNA. CONCLUSIONS: We suppose that proteomic approach for TBP identification may be promising in development of biomarkers, also obtained results may be valuable for further understanding TBP functions in genome.


Assuntos
Biomarcadores Tumorais/isolamento & purificação , Proteínas de Ligação a DNA/isolamento & purificação , Proteínas de Ligação a DNA/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Animais , Biomarcadores Tumorais/metabolismo , Enzimas Reparadoras do DNA/isolamento & purificação , Enzimas Reparadoras do DNA/metabolismo , Proteínas de Ligação a DNA/genética , Fígado/metabolismo , Neoplasias Hepáticas Experimentais/genética , Matriz Nuclear , Proteínas Associadas à Matriz Nuclear/isolamento & purificação , Proteínas Associadas à Matriz Nuclear/metabolismo , Prognóstico , Ligação Proteica , Proteômica , RNA Helicases/isolamento & purificação , RNA Helicases/metabolismo , Ratos , Ratos Wistar , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
5.
Biomed Khim ; 57(5): 490-500, 2011.
Artigo em Russo | MEDLINE | ID: mdl-22629599

RESUMO

Streptozotocin (STZ) was used to induce the diabetic rat model. STZ rats were treated with mildronate (100 mg/kg daily, per os or intraperitoneally for 6 weeks). Body weight, blood glucose, triglyceride, ketone body concentrations, glycated hemoglobin percent (HbA1c%), glucose tolerance, and the development of neuropathic pain were monitored throughout the experiment. In the STZ + mildronate group, mildronate treatment caused a significant decrease in mean blood glucose (on week 4) and triglyceride concentrations (on weeks 3-6), significantly slowed the increase in HbA1c% (on week 6) and improved glucose tolerance 120 minutes after glucose ingestion during oral glucose tolerance test versus the STZ group. Mildronate completely protected development of STZ-induced neuropathic pain from the first administration week up to end of the experiment. The obtained data indicate clinical usefulness of the drug for the treatment of diabetes mellitus and its complications.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Experimental/complicações , Neuropatias Diabéticas/tratamento farmacológico , Metabolismo dos Lipídeos , Metilidrazinas/uso terapêutico , Neuralgia/tratamento farmacológico , Animais , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/induzido quimicamente , Teste de Tolerância a Glucose , Hemoglobinas Glicadas/metabolismo , Lipídeos/sangue , Masculino , Metilidrazinas/administração & dosagem , Limiar da Dor , Ratos , Ratos Wistar , Estreptozocina/efeitos adversos
6.
Biochemistry (Mosc) ; 75(10): 1240-51, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21166641

RESUMO

Proteins tightly bound to DNA (TBP) comprise a group of proteins that remain bound to DNA after usual deproteinization procedures such as salting out and treatment with phenol or chloroform. TBP bind to DNA by covalent phosphotriester and noncovalent ionic and hydrogen bonds. Some TBP are conservative, and they are usually covalently bound to DNA. However, the TBP composition is very diverse and significantly different in different tissues and in different organisms. TBP include transcription factors, enzymes of the ubiquitin-proteasome system, phosphatases, protein kinases, serpins, and proteins of retrotransposons. Their distribution within the genome is nonrandom. However, the DNA primary structure or DNA curvatures do not define the affinity of TBP to DNA. But there are repetitive DNA sequences with which TBP interact more often. The TBP distribution within genes and chromosomes depends on a cell's physiological state, differentiation type, and stage of organism development. TBP do not interact with DNA in the sites of its association with nuclear matrix and most likely they are not components of the latter.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , DNA/química , DNA/genética , DNA/metabolismo , Animais , Cromossomos Humanos/química , Cromossomos Humanos/genética , Cromossomos Humanos/metabolismo , Humanos , Especificidade de Órgãos
7.
Eur J Histochem ; 51(2): 81-94, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17664158

RESUMO

The present review summarizes data on the accumulation of DNA strand breaks in differentiating cells. Large 50 Kbp free DNA fragments were observed by several research teams in non-apoptotic insect, mammal and plant cells. A more intensive DNA breakage was observed during maturation of spermatides, embryo development, and differentiation of myotubes, epidermal cells, lymphocytes and neutrophils. In general, accumulation of DNA strand breaks in differentiating cells cannot be attributed to decrease of the DNA repair efficiency. Poly(ADP)ribose synthesis often follows the DNA breakage in differentiating cells. We hypothesize that DNA fragmentation is an epigenetic tool for regulation of the differentiation process. Scarce data on localization of the differentiation-associated DNA strand breaks indicate their preferred accumulation in specific DNA sequences including the nuclear matrix attachment sites and repeats. Recent data on non-apoptotic functions of caspases provide more evidence for possible existence of a DNA breakage mechanism in differentiating cells resembling the initial stage of apoptosis. Excision of methylated cytosine and recombination are other possible explanations of the phenomenon. Elucidation of mechanisms of differentiation-induced DNA strand breaks appears to possess considerable research potential.


Assuntos
Diferenciação Celular/fisiologia , Quebras de DNA de Cadeia Dupla , Quebras de DNA de Cadeia Simples , Animais , Apoptose , Diferenciação Celular/genética , Fragmentação do DNA , Reparo do DNA , Desenvolvimento Embrionário , Feminino , Hematopoese , Humanos , Masculino , Modelos Biológicos , Mioblastos/citologia , Mioblastos/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Células Vegetais , Plantas/metabolismo , Poli Adenosina Difosfato Ribose/metabolismo , Recombinação Genética , Espermatogênese
8.
Nitric Oxide ; 17(3-4): 107-14, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17702619

RESUMO

We have studied the impact of two novel compounds TO-85 (2,6-di-(alpha-aziridino-alpha-hydroxyiminomethyl)pyridine and TO-133 (bis-(diaziridinoglyoximato)copper), designed as NO donors, on nitrite production by cell cultures, NO production in rat tissues and their ability to inhibit purified NO synthases (NOS). Both substances induced considerable increase of nitrite production in cell cultures. When NO production was assayed in rat organs by means of ESR using Fe(DETC) as a spin trap the anticipated NO-increasing activity of TO-85 was observed only in kidneys; the NO level increasing almost 10-fold. Treatment of rats with TO-133, decreased the NO concentration in brain cortex, cerebellum and liver. When the drugs were administered to animals with high level of iNOS expression induced by LPS, TO-85 did not significantly modify the LPS-induced NO production; administration of TO-133 caused a significant decrease of NO production in blood, brain cortex and cerebellum. Only high concentrations of TO-85 were capable of inhibiting iNOS (IC50=7 mM), the substance inhibited eNOS at lower concentrations (IC50=250 microM). Inhibitory activities of TO-85 on nNOS were dependent on BH4 concentrations, suggesting eventual competition of TO-85 with BH4 when the substance interacts with nNOS. TO-133 reduced eNOS activity with IC50=200 microM, nNOS activity with IC50=200 microM, iNOS activity was not much affected by this substance. Thus, the two tested compounds manifest opposite effects on NO production by purified enzymes and in cell culture. The pattern of the NO synthesis modification in a living animal appears to be even more complex. Our results stress the importance of direct measurements of NO in the tissues using the ESR method.


Assuntos
Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/metabolismo , Oximas/farmacologia , Animais , Arginina/metabolismo , Aziridinas/farmacologia , Biopterinas/análogos & derivados , Biopterinas/metabolismo , Linhagem Celular Tumoral , Ácido Cítrico , Ditiocarb/química , Espectroscopia de Ressonância de Spin Eletrônica , Compostos Ferrosos/química , Humanos , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Estrutura Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/sangue , Óxido Nítrico Sintase Tipo I/antagonistas & inibidores , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/química , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Óxido Nítrico Sintase Tipo III/metabolismo , Ratos , Ratos Wistar , Detecção de Spin/métodos
9.
Genetika ; 43(5): 581-600, 2007 May.
Artigo em Russo | MEDLINE | ID: mdl-17633552

RESUMO

The review summarizes the authors' and literature data on accumulation of DNA breaks in differentiating cells. Large 50-kb free DNA fragments were observed by several research teams in non-apoptotic insect, mammal, and plant cells. More intense DNA breakage was observed during maturation of spermatides, embryo development, and differentiation of myotubes, epidermal cells, lymphocytes, and neutrophils. In general, accumulation of DNA breaks in differentiating cells cannot be attributed to a decrease in the DNA repair efficiency. Poly(ADP)ribose synthesis often follows the DNA breakage in differentiating cells. We hypothesize that DNA fragmentation is an epigenetic tool for regulating the differentiation process. Scarce data on localization of the differentiation-associated DNA breaks indicate their preferable accumulation in specific DNA sequences including the nuclear matrix attachment sites. he same sites are degraded at early stages of apoptosis. Recent data on non-apoptotic function of caspases provide more evidence for possible existence of a DNA breakage mechanism in differentiating cells, resembling the initial stage of apoptosis. Excision of methylated cytosine and recombination are other possible explanations of the phenomenon. Elucidation of mechanisms of differentiation-induced DNA breaks appears to be a prospective research direction.


Assuntos
Diferenciação Celular/genética , Quebras de DNA , Fragmentação do DNA , Epigênese Genética , Poli Adenosina Difosfato Ribose/metabolismo , Animais , Apoptose , Caspases/metabolismo , Humanos
10.
Genetika ; 43(4): 553-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17555133

RESUMO

In our preceding studies we have identified microsatellite polymorphisms inside the PSMA6 gene and in its 5' upstream region. Following the observed associations of microsatellite polymorphisms with non-insulin dependent diabetes mellitus and Graves' disease we extended the evaluation of PSMA6 genetic variations to cardiovascular disorders and non-insulin dependent diabetes mellitus. New polymorphisms in the promoter region and exon 6 of the gene were identified by direct sequencing of the promoter region and all seven exons of the gene in 30 individuals of European descent. Two SNPs at positions -110 and -8 from the translation start, in the promoter region and 5'UTR respectively, were analyzed. Neither polymorphism was associated with the risk of myocardial infarction. No significant association of the polymorphisms with plasma lipid levels or BMI was observed. A borderline association of both polymorphisms with diastolic blood pressure was observed in the control group. Genotype -8CG was significantly more frequent in type 2 diabetes patients, and haplotype C-110/G-8, compared to C-110/C-8 was associated with a higher risk of NIDDM.


Assuntos
Diabetes Mellitus Tipo 2/genética , Complexos Multienzimáticos/genética , Infarto do Miocárdio/genética , Polimorfismo de Nucleotídeo Único , Complexo de Endopeptidases do Proteassoma/genética , Códon de Iniciação/genética , Diabetes Mellitus Tipo 2/sangue , Éxons/genética , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Regiões Promotoras Genéticas/genética , Fatores de Risco
11.
Ann Hum Genet ; 71(Pt 6): 772-6, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17535269

RESUMO

A polymorphic microsatellite in intron 6 of the human proteasome core particle PSMA6 gene (HSMS006), and four other microsatellites localized upstream on human chromosome 14q13.2 (HSMS801, HSMS702, HSMS701, HSMS602), were genotyped in 104 type 2 diabetic patients and 129 age-matched control subjects from Latvia and replicated in 91 type 2 diabetic patients and 88 age-matched healthy control subjects from the Botnia Study in Finland. In type 2 diabetic patients from both populations the HSMS006 (TG)22 allele was two times more frequent compared to the control group. In the Latvian population the (CAA)8 allele of the HSMS602 marker was less frequent in the diabetic group, as was the (AC)24 allele of microsatellite HSMS801. Allele frequencies of the HSMS701 and 702 repeats were similar in healthy controls and type 2 diabetic patients. In conclusion, our data suggest that variants in the PSMA6 gene on chromosome 14q13.2 are associated with type 2 diabetes.


Assuntos
Cromossomos Humanos Par 14/genética , Diabetes Mellitus Tipo 2/genética , Repetições de Microssatélites , Polimorfismo Genético , Adulto , Idoso , Alelos , Estudos de Casos e Controles , Feminino , Finlândia , Frequência do Gene , Humanos , Letônia , Masculino , Pessoa de Meia-Idade , Complexos Multienzimáticos/genética , Complexo de Endopeptidases do Proteassoma/genética
12.
Biomed Khim ; 53(6): 672-82, 2007.
Artigo em Russo | MEDLINE | ID: mdl-18323152

RESUMO

We have investigated effects of Mildronate, gamma-butyrobetaine (GBB) and their combination ("Neomildronate") on the plasma levels of thyroid gland hormones and some intermediates of basal metabolism (free fatty acids, triglycerides, glucose) in rats with different dysfunctions of thyroid gland, including idiopathic hyperfunction and hypofunction induced by propylthiouracil or L-carnitin administration. Histological investigation of the thyroid gland was also performed. Intraperitoneal injections of Mildronate (150 mg/kg) during 20 days to Wistar male rats with elevated level of thyroid hormones and basal metabolism normalized thyroxine level and parameters of lipid metabolism. Mildronate, GBB and their combination did not affect the natural resurgence of rats with experimental hypofunction induced by propylthiouracil or L-carnitin administration. The possible biochemical role of given treatment in regulation of thyroid gland function is discussed.


Assuntos
Betaína/análogos & derivados , Metabolismo dos Carboidratos/efeitos dos fármacos , Fármacos Cardiovasculares/farmacologia , Carnitina/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Metilidrazinas/farmacologia , Doenças da Glândula Tireoide/sangue , Tiroxina/sangue , Animais , Antitireóideos/toxicidade , Betaína/farmacologia , Carnitina/toxicidade , Masculino , Propiltiouracila/toxicidade , Ratos , Ratos Wistar , Doenças da Glândula Tireoide/induzido quimicamente , Doenças da Glândula Tireoide/patologia , Glândula Tireoide/metabolismo , Glândula Tireoide/patologia , Complexo Vitamínico B/toxicidade
13.
Genetika ; 41(3): 293-8, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15865282

RESUMO

The review summarizes literature data on alterations of structure or expression of different nuclear matrix proteins in hereditary syndromes. From the point of view of involvement of nuclear matrix proteins in etiology and pathogenesis of the disease hereditary pathologies can be classified in pathologies with pathogenesis associated with defects of nuclear matrix proteins and pathologies associated to changes of the nuclear matrix protein spectrum. The first group includes laminopathies, hereditary diseases with abnormal nuclear-matrix associated proteins and triplet extension diseases associated with accumulation of abnormal proteins in the nuclear matrix. Laminopathies are hereditary diseases coupled to structural defects of the nuclear lamina. These diseases include Emery-Dreifuss muscular dystrophy, limb girdle muscular dystrophy, dilated cardiomyopathy (DCM) with conduction system disease, familial partial lipodystrophy (FPLD), autosomal recessive axonal neuropathy (Charcot-Marie-Tooth disorder type 2, CMT2), mandibuloacral dysplasia (MAD), Hutchison Gilford Progeria syndrome (HGS), Greenberg Skeletal Dysplasia, and Pelger-Huet anomaly (PHA). Most of them are due to mutations in the lamin A/C gene, one - to mutations in emerin gene, some are associated with mutations in Lamin B receptor gene. In Werner's, Bloom's, Cockayne's syndromes, Fanconi anemia, multiple carboxylase deficiency mutations in nuclear matrix protein or enzyme gene lead to deficient DNA repair, abnormal regulation of cell growth and differentiation or other specific metabolic functions. Proteins with a long polyglutamic tract synthesized in the cells of patients with dentato-rubral and pallido-luysian atrophy, myotonic dystrophy and Huntington disease interfere with transcription on the nuclear matrix. Down's syndrome is a representative of the group of diseases with altered nuclear matrix protein spectrum.


Assuntos
Doenças Genéticas Inatas/genética , Proteínas Associadas à Matriz Nuclear/genética , Animais , Reparo do DNA/genética , Regulação da Expressão Gênica , Humanos
15.
Acta Anaesthesiol Scand ; 46(4): 378-83, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11952436

RESUMO

BACKGROUND: Halogenated volatile anesthetics (HVAs) are considered to be inhibitors of nitric oxide synthase (NOS). On other hand, NO mediates the vasodilation produced by HVAs. Thus, both increase and decrease of NO concentration in brain tissues are possible during anesthesia. Previously, we have observed an increase of NO content in rat brain cortex under halothane anesthesia. The goal of this study was to determine whether the observed phenomenon was general for this anesthetic group, if it was specific for brain cortex, and if the NO increase was due changes in NOS activity. METHODS: NO scavengers were injected to adult rats 30 min prior to anesthesia. Rats were anesthetized by inhalation of an O2 mixture with volatile anesthetics (1.5% for halothane; 1% for isoflurane, 2% for sevoflurane). After 30 min of anesthesia, rats were decapitated and brain cortex, cerebellum, liver, heart, kidneys and testes were dissected, frozen in liquid nitrogen and subjected to EPR spectroscopy. Nitric oxide content was determined quantitatively based on the intensity of the NO-Fe-DETC complex spectrum and its comparison with the calibration curve. RESULTS: In rats anesthetized with HVAs, we observed a greater than twofold increase of NO content in brain cortex as compared to the nonanesthetized animals. No significant changes were detected in other organs. The NOS inhibitor N(omega)-nitro-L-arginine abolished the increase of NO content in brain produced by volatile anesthetics. CONCLUSION: The action of volatile anesthetics is coupled with an increase of NO content in the cortex dependent on NOS activity.


Assuntos
Anestésicos Inalatórios/farmacologia , Química Encefálica/efeitos dos fármacos , Córtex Cerebral/metabolismo , Óxido Nítrico/biossíntese , Trifosfato de Adenosina/metabolismo , Animais , Calibragem , Córtex Cerebral/efeitos dos fármacos , Espectroscopia de Ressonância de Spin Eletrônica , Metabolismo Energético/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Halotano/farmacologia , Isoflurano/farmacologia , Ácido Láctico/metabolismo , Masculino , Éteres Metílicos/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Nitroarginina/farmacologia , Ácido Pirúvico/metabolismo , Ratos , Ratos Wistar , Sevoflurano , Detecção de Spin , Estimulação Química
16.
Genetika ; 38(12): 1589-606, 2002 Dec.
Artigo em Russo | MEDLINE | ID: mdl-12575443

RESUMO

The data on the genomic domain structure of both mammalian and avian alpha- and beta-globin genes are reviewed. The specific features of chromatin, DNA binding to the nuclear matrix, and domain-specific transcripts are discussed. In humans, the beta-globin gene domain is located in the GC-depleted isochore and contains multiple nuclear matrix attachment regions. The locus is controlled by six chromatin regions hypersensitive to DNase located far upstream of the first structural gene. Some of these regions display enhancer activity to support normal transcription level in the domain. Other mammalian beta-globin domains are similarly organized. The avian beta-globin genes are specifically arranged and their expression is less dependent from the locus control region. The human alpha-globin gene is located in the GC-rich isochore. The nuclear matrix attachment sites are not identified in this gene. An analog of the locus control region is located 40 kb upstream of the zeta-globin gene. The avian alpha-globin gene domains contain numerous nuclear matrix attachment regions. In these domains, an element located far upstream the genes regulates positive rather than negative transcription. An unidentified housekeeping gene as well as some other transcripts not encoding the structural globin genes is transcribed in the direction opposite to that of the globin genes in both mammalian and avian domains.


Assuntos
Aves/genética , Globinas/química , Globinas/genética , Mamíferos/genética , Animais , Núcleo Celular/genética , Núcleo Celular/metabolismo , Cromatina/química , Cromatina/genética , Cromatina/metabolismo , DNA Topoisomerases/genética , DNA Topoisomerases/metabolismo , Desoxirribonucleases/genética , Desoxirribonucleases/metabolismo , Elementos Facilitadores Genéticos , Humanos , Região de Controle de Locus Gênico , Conformação de Ácido Nucleico , Recombinação Genética , Transcrição Gênica
17.
Exp Cell Res ; 270(2): 159-65, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11640880

RESUMO

Using hybridization in situ with a ribo-probe recognizing transcripts of the chicken alpha A globin gene, we show here that in proliferating AEV-transformed erythroblasts this gene is strongly transcribed, but the corresponding transcripts are retained in the nuclei. Most surprisingly, this globin RNA accumulates in the perinucleolar areas in a pattern never observed before. Upon induction of cells to differentiate, leading to productive expression of the hemoglobins, the transcripts of the alpha A globin gene were found for the most part in the cytoplasm. In the nuclei of differentiated cells, the globin RNA is concentrated in one or two specific spots, which are likely to represent the "processing centers" (PCs) of the globin RNA. The results presented indicate that posttranscriptional steps of regulation involving in particular the perinuclear areas are of major importance for erythroid differentiation.


Assuntos
Nucléolo Celular/genética , Nucléolo Celular/metabolismo , Globinas/genética , Leucemia , Precursores de RNA/metabolismo , Transcrição Gênica/fisiologia , Animais , Northern Blotting , Diferenciação Celular/fisiologia , Divisão Celular/fisiologia , Galinhas , Citoplasma/metabolismo , Precursores de RNA/análise , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Células Tumorais Cultivadas
18.
Anesteziol Reanimatol ; (3): 61-5, 2001.
Artigo em Russo | MEDLINE | ID: mdl-11510365

RESUMO

Published reports on modifications of nitric oxide (NO) synthase (NOS) activity and NO production in the brain during development of anesthesia induced by the most common inhalational (halothane, isoflurane, sevoflurane, enflurane) and intravenous (ketamine, barbiturates, propofol, etomidate) anesthetics are reviewed. According to a popular universally acknowledged hypothesis, inhibition of NOS activity and blockade of NO neurotransmitter function are important steps in the mechanism of action of anesthetics. There are data which confirm the validity of this hypothesis for all above-listed drugs, but there are also data which disagree with it. Some scientists find that anesthesia has no effect on NOS activity and NO production, others found that the enzyme activity and NOS gene expression increased under the effect of anesthesia. Published reports and authors' data on a drastic increase of NO content in the cerebral cortex in halothane anesthesia are discussed. The effects of narcotics on NO-mediated changes in vascular tone are analyzed.


Assuntos
Anestésicos/farmacologia , Encéfalo/efeitos dos fármacos , Óxido Nítrico Sintase/fisiologia , Óxido Nítrico/biossíntese , Anestésicos/administração & dosagem , Anestésicos Inalatórios/administração & dosagem , Anestésicos Inalatórios/farmacologia , Anestésicos Intravenosos/administração & dosagem , Anestésicos Intravenosos/farmacologia , Animais , Encéfalo/metabolismo , Expressão Gênica , Humanos , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase/efeitos dos fármacos , Óxido Nítrico Sintase/genética , Ratos , Fatores de Tempo
19.
DNA Seq ; 12(4): 261-5, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11924531

RESUMO

The exon/intron structure of the human proteasome PROS-27 gene was established by means of partial sequencing of its genomic clones and comparison with the chromosome 14 sequences from the data bases. The gene contains seven exons spanning over 19kb. Introns of the gene contain numerous Alu type repeats, Mer 2 and LINE type repeats. Pattern of the repeats indicates conservatism of the sequence.


Assuntos
Cisteína Endopeptidases/genética , Íntrons/genética , Complexos Multienzimáticos/genética , Humanos , Complexo de Endopeptidases do Proteassoma , Sequências Repetitivas de Ácido Nucleico , Análise de Sequência de DNA
20.
Mol Gen Genet ; 262(6): 1012-21, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10660062

RESUMO

A novel gene transcribed in the direction opposite to that of the globin genes was found in the chicken alpha-globin gene domain. Northern hybridisation with single-stranded riboprobes revealed that a 4.5-kb poly(A)+ RNA is transcribed in antisense polarity with respect to the globin genes. The transcription unit encoding this RNA seems to overlap the entire cluster of alpha-globin genes and extends at least 15 kb upstream from pi, the first of the alpha-globin genes. This new transcript shows partial sequence homology with that encoded by the human "-14" gene. An oligonucleotide based on part of a restriction fragment of chicken DNA that is 80% homologous to exon 4 of the human "-14" gene hybridises with a 4.5-kb RNA molecule. In situ hybridisation of globin-antisense probes, that detect polyribosomal mRNAs of 1.7 and 2.5 kb on Northern blots, shows these "antisense" transcripts to be present in the cytoplasm. The 4.5-kb RNA is absent in polyribosomal poly(A)+ RNA and may, hence, represent a nuclear pre-mRNA transcribed from the chicken gene that is homologous to the human "-14" gene. The expression of this gene is not specific to erythroid cells; analogous transcripts were also detected in poly(A)+ RNA extracted from a chicken lymphoblastoma cell line (HP50). Taken together, these data allow us to postulate the existence in the chicken genome of a novel gene, for which we suggest the name "ggPRX" in analogy to the murine mProx1, a gene identified in the upstream region of the alpha-globin gene domain in mice.


Assuntos
Globinas/genética , Família Multigênica , Animais , Sequência de Bases , Linhagem Celular , Núcleo Celular/metabolismo , Galinhas , Mapeamento Cromossômico , Citoplasma/metabolismo , Éxons , Humanos , Camundongos , Dados de Sequência Molecular , Sondas RNA/genética , RNA Antissenso/genética , RNA Antissenso/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Transcrição Gênica
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