RESUMO
Our previous study demonstrated that phospholipase C beta 1 mRNA was down-regulated in Brodmann's area 46 from subjects with schizophrenia. However, phospholipase C beta 1 protein has also been shown to be lower in Brodmann's area 8 and 9 from teenage suicide subjects, creating a potential confound in interpreting the findings in schizophrenia due to the high suicide rate associated with this disorder. To begin to reconcile and consolidate these findings, in this study, we measured mRNA and protein levels of phospholipase C beta 1 variants a and b in Brodmann's area 46 and Brodmann's area 9 from subjects with schizophrenia, many of whom were suicide completers, and determined the diagnostic specificity of observed findings. Consistent with our previous study, levels of phospholipase C beta 1 a and b mRNA, but not protein, were lower in Brodmann's area 46 from subjects with schizophrenia. In Brodmann's area 9, phospholipase C beta 1a protein levels were lower in subjects with schizophrenia, while phospholipase C beta 1b mRNA was higher and protein was lower in those that had died of suicide. Altered protein levels in Brodmann's area 9 appeared to be diagnostically specific, as we did not detect these changes in subjects with bipolar disorder, major depressive disorder or suicide completers with no diagnosis of mental illness. We further assessed the relationship between phospholipase C beta 1 and levels of muscarinic receptors (CHRMs) that signal through this protein, in both human and Chrm knockout mouse central nervous system tissue, and found no strong relationship between the two. Understanding central nervous system differences in downstream effector pathways in schizophrenia may lead to improved treatment strategies and help to identify those at risk of suicide.
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OBJECTIVE: To investigate the anti-obesity effect of Rubi Fructus (RF) extract using brown adipose tissue (BAT) and primary brown preadipocytes in vivo and in vitro. METHODS: Male C57BL/6 J mice (n=5 per group) were fed a high-fat diet (HFD) for 10 weeks with or without RF. Brown preadipocytes from the interscapular BAT of mice (age, post-natal days 1-3) were cultured with differentiation media (DM) including isobutylmethylxanthine, dexamethasone, T3, indomethacin and insulin with or without RF. RESULTS: In HFD-induced obese C57BL/6 J mice, long-term RF treatment significantly reduced weight gain as well as the weights of the white adipose tissue, liver and spleen. Serum levels of total cholesterol and low-density lipoprotein cholesterol were also reduced in the HFD group which received RF treatment. Furthermore, RF induced thermogenic-, adipogenic- and mitochondria-related gene expressions in BAT. In primary brown adipocytes, RF effectively stimulated the expressions of thermogenic- and mitochondria-related genes. In addition, to examine whether LIPIN1, a regulator of adipocyte differentiation, is regulated by RF, Lipin1 small interfering RNA (siRNA) and RF were pretreated in primary brown adipocytes. Pretreatment with Lipin1 siRNA and RF downregulated the DM-induced expression levels of thermogenic- and mitochondria-related genes. Moreover, RF markedly upregulated AMP-activated protein kinase. Our study shows that RF is capable of stimulating the differentiation of brown adipocytes through the modulation of thermogenic genes. CONCLUSIONS: This study demonstrates that RF prevents the development of obesity in mice fed with a HFD and that it is also capable of stimulating the differentiation of brown adipocytes through the modulation of thermogenic genes, which suggests that RF has potential as a therapeutic application for the treatment or prevention of obesity.
Assuntos
Adipócitos Marrons/metabolismo , Adipogenia/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Obesidade/patologia , Preparações de Plantas/farmacologia , Rubus , Termogênese/genética , Animais , Dieta Hiperlipídica , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Termogênese/efeitos dos fármacosRESUMO
BACKGROUND: Nasal polyposis is characterized by tissue remodelling and oedematous nasal mucosa. Vascular endothelial growth factor (VEGF) plays a significant role in the regulation of remodelling in nasal polyps. TLR4 activation is associated with VEGF expression in murine macrophages and odontoblasts. OBJECTIVE: This study aimed to evaluate whether lipopolysaccharide (LPS), an inducer of TLR4, stimulates VEGF expression and to determine the mechanism underlying VEGF production in nasal polyps. METHODS: Nasal polyp-derived fibroblasts (NPDFs) were isolated from 10 patients with nasal polyps and exposed to LPS. LPS from Rhodobacter sphaeroides (LRS) was used to inhibit the expression levels of TLR4, MyD88 and VEGF. Messenger RNA (mRNA) expression levels of TLRs, MyD88 and VEGF were determined by gene expression microarray and semiquantitative reverse transcription-PCR. Protein expression levels of TLR4 and VEGF were analysed using western blot, immunofluorescence staining and enzyme-linked immunosorbent assay (ELISA). Activation of MAPKs (ERK, p38, and JNK) and Akt was examined using western blot analysis. The expression level of VEGF was measured by ELISA and western blot analysis in ex vivo nasal polyp organ culture. RESULTS: The protein expression level of VEGF was increased in nasal polyp tissues compared with inferior turbinate tissues. LRS inhibited the mRNA and protein expression of TLR4, MyD88 and VEGF in LPS-stimulated NPDFs. LPS-activated MAPKs and Akt signals, whereas MAPK inhibitors did not inhibit VEGF expression, and only Akt inhibitor blocked VEGF production. LRS reduced the production of VEGF in LPS-stimulated ex vivo organ culture. CONCLUSIONS AND CLINICAL RELEVANCE: These results suggest that LPS stimulates the production of VEGF through the TLR4-Akt signalling pathway in nasal polyps. LPS may be involved in the pathogenesis of nasal polyp remodelling.
Assuntos
Regulação da Expressão Gênica , Pólipos Nasais/genética , Pólipos Nasais/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Ativação Enzimática , Fibroblastos/imunologia , Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Sistema de Sinalização das MAP Quinases , Pólipos Nasais/imunologia , Técnicas de Cultura de Órgãos , Transcriptoma , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
BACKGROUND: Nasal polyposis is a multi-factorial disease associated with chronic inflammatory condition of the paranasal sinuses. Myofibroblast differentiation and extracellular matrix (ECM) accumulation are involved in the pathogenesis of nasal polyposis. OBJECTIVE: The aim of this study was to study the effect of trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, on transforming growth factor (TGF)-ß1-induced myofibroblast differentiation and ECM accumulation in nasal polyp-derived fibroblasts (NPDFs). METHODS: Nasal polyp-derived fibroblasts were isolated from nasal polyps of patients who have chronic rhinosinusitis with nasal polyp. TSA was treated in TGF-ß1-induced NPDFs. Expression levels of HDAC2, α-smooth muscle actin (SMA), TGF-ß1, collagen type I, acetylated Histone H3, acetylated Histone H4, phosphorylated Smad2/3 and Smad7 were determined by RT-PCR, western blot and/or immunofluorescent staining. The total collagen amount production was analysed by Sircol soluble collagen assay and contractile activity was measured by collagen gel contraction assay. HDAC2 inhibition by TSA or HDAC2 silencing was established by RT-PCR and western blot. The epigenetic effect on α-SMA gene inactivation was examined by chromatin immunoprecipitation assay. Proliferation was determined by Ki67-positive cell staining and cytotoxicity was assessed by 3-(4,5- dimethylthiazol-2yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. RESULTS: The expression levels of HDAC2, α-SMA and TGF-ß1 were increased in nasal polyp tissues compared to normal inferior turbinate tissues. TSA and HDAC2 silencing inhibited expression levels α-SMA, collagen and HDAC2. TSA induced hyperacetylation of histone and suppressed opening of α-SMA gene promoter in TGF-ß1-induced NPDFs. TSA inhibited TGF-ß1-induced Smad 2/3 and rescued TGF-ß1-suppressed Smad7 signalling pathway. Finally, TSA blocked proliferation in TGF-ß1-induced NPDFs and has no cytotoxic effect in NPDFs. CONCLUSIONS AND CLINICAL RELEVANCE: These results suggest that HDAC inhibition is associated with myofibroblast differentiation and extracelluar matrix accumulation in nasal polyposis. TSA may be useful as an inhibitor of nasal polyp growth, and thus has potential to be used as a novel treatment option for nasal polyposis.
Assuntos
Diferenciação Celular , Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Miofibroblastos/citologia , Miofibroblastos/metabolismo , Pólipos Nasais/genética , Pólipos Nasais/metabolismo , Acetilação/efeitos dos fármacos , Actinas/genética , Actinas/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Epigênese Genética , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Histona Desacetilase 2/antagonistas & inibidores , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Histonas/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Fosforilação/efeitos dos fármacos , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismoRESUMO
Histidine decarboxylase (HDC) catalyzes the formation of histamine from histidine. Histamine has various effects in physiological and pathological reactions, such as inflammation, cell growth, and neuro-transmission. We investigated the role of hypoxia-inducible factor (HIF)-1 on hypoxia-induced HDC expression in human mast cell line, HMC-1 cells and mouse bone marrow-derived mast cells (BMMCs). Hypoxia significantly increased histamine production. HDC expression and activity were induced by hypoxia. Additionally, when cells were transfected with a native form of HIF-1alpha, hypoxia could induce higher HDC expression than in the nontransfected cell. HIF-1 binding activity for HDC 5' flanking region (HFR) was similar to that for the hypoxia-responsive element. Using HDC promoter deletion analysis, we also demonstrated that HFR was regulated by HIF-1 activation. In addition, depletion of HIF-1alpha prevents hypoxic induction of HDC in BMMCs. In conclusion, these results demonstrate that hypoxia induces HDC expression by transcriptional mechanisms dependent upon HIF-1.
Assuntos
Regulação Enzimológica da Expressão Gênica/fisiologia , Histamina/biossíntese , Histidina Descarboxilase/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Mastócitos/metabolismo , Animais , Células da Medula Óssea/fisiologia , Hipóxia Celular , Células Cultivadas , Feminino , Humanos , Camundongos , Regiões Promotoras Genéticas , Fator A de Crescimento do Endotélio Vascular/biossínteseRESUMO
BACKGROUND: Rumex japonicus Houtt. (RJH) is one of the herbs used in Eastern countries for the treatment of atopic dermatitis (AD). It has been shown to have an antioxidative effect in human skin disease. OBJECTIVES: To examine whether RJH extract (RJH-E) suppresses the development of AD-like skin lesions in NC/Nga mice, which are induced by the repeated application of picryl chloride (PC). METHODS: The efficacy of RJH-E in NC/Nga mice was assessed by measuring symptom severity, scratching behaviour, Staphylococcus aureus numbers on an ear, and serum levels of IgE, interleukin (IL)-4 and interferon (IFN)-gamma. RESULTS: Oral administration of RJH-E to NC/Nga mice treated with PC inhibited the development of AD-like skin lesions as exemplified by a significant decrease in total skin symptom severity scores, and a decrease in hypertrophy, hyperkeratosis and infiltration of inflammatory cells in the skin. The scratching behaviour and numbers of S. aureus, which are known to be exacerbated in AD, were also significantly reduced by RJH-E. No significant change was observed in the serum levels of IFN-gamma, whereas IgE and IL-4 levels were significantly reduced by RJH-E. CONCLUSIONS: These results suggest that RJH-E inhibits the development of AD-like skin lesions in NC/Nga mice by suppressing the T-helper 2 cell response. Our results indicate that RJH treatment could provide an effective alternative therapy for the management of AD.
Assuntos
Dermatite Atópica/tratamento farmacológico , Fitoterapia/métodos , Extratos Vegetais/uso terapêutico , Plantas Medicinais , Rumex , Animais , Dermatite Atópica/imunologia , Dermatite Atópica/microbiologia , Feminino , Imunoglobulina E/sangue , Interferon gama/sangue , Interleucina-4/sangue , Testes de Função Hepática , Camundongos , Camundongos Mutantes , Modelos Animais , Cloreto de Picrila , Raízes de Plantas , Pele/efeitos dos fármacos , Infecções Estafilocócicas/complicações , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/isolamento & purificação , Resultado do TratamentoRESUMO
BACKGROUND: Alginic acid is comprised of complex polymerized polysaccharides, and can be chemically extracted from seaweed. Alginic acid has an inhibitory effect on histamine release, but its molecular mechanisms are not well understood. OBJECTIVE: To investigate the effect of alginic acid on the mast cell-mediated anaphylactic and inflammatory reaction using in vivo and in vitro models and elucidate its molecular mechanisms. MATERIALS AND METHOD: The effect of alginic acid on an allergy model was analysed by anaphylaxis, a histidine decarboxylase (HDC) assay, and a histamine assay. Cytokine production was analysed by means of ELISA. Cytokine expression was analysed by means of RT-PCR, and Western blotting. Transcription factor activity was analysed by a luciferase assay and a transcription factor-enzyme linked immunoassay. RESULTS: Alginic acid dose dependently inhibited compound 48/80-induced systemic anaphylaxis with doses of 0.25-1 g/kg 1 h (P<0.01, n=6) and significantly inhibited passive cutaneous anaphylaxis by 54.8%. Alginic acid (0.01-1 microg/mL) inhibited histamine release from serum and peritoneal mast cells (P<0.01). All these effects were stronger than those of disodium cromoglycate (DSCG), the reference drug tested. Alginic acid also inhibited HDC expression and activity on the phorbol myristate acetate (PMA)+A23187-stimulated human mast cell line, HMC-1 cells. Moreover, alginic acid significantly inhibited the production of PMA+A23187-induced inflammatory cytokines, IL-1beta and TNF-alpha, but not that of IL-6 or IL-8. In activated HMC-1 cells, the expression level of nuclear factor (NF)-kappaB/Rel A protein increased in the nucleus, whereas the level of NF-kappaB/Rel A in the nucleus was decreased by alginic acid treatment. In addition, alginic acid (0.01 microg/mL) decreased the PMA+A23187-induced luciferase activity and DNA-binding activity. CONCLUSION: The present results indicate that alginic acid has potent anti-anaphylactic and anti-inflammatory properties.
Assuntos
Alginatos/farmacologia , Antialérgicos/farmacologia , Citocinas/análise , Mastócitos/metabolismo , NF-kappa B/metabolismo , Animais , Western Blotting/métodos , Calcimicina , Linhagem Celular , Citocinas/imunologia , Citocinas/metabolismo , Ácido Glucurônico/farmacologia , Ácidos Hexurônicos/farmacologia , Liberação de Histamina , Histidina Descarboxilase/análise , Histidina Descarboxilase/metabolismo , Ionóforos , Masculino , Mastócitos/efeitos dos fármacos , Mastócitos/imunologia , Modelos Animais , Anafilaxia Cutânea Passiva , Peritônio , Ratos , Ratos Wistar , Testes Cutâneos , Acetato de Tetradecanoilforbol , p-Metoxi-N-metilfenetilaminaRESUMO
Jeongshintang (JST) is a Korean herbal prescription, which has been successfully used for cerebral diseases. However, the anti-inflammatory effect of JST on Alzheimer's disease (AD) is still not fully understood. In this study, we investigated the effects of JST in attenuating the inflammatory response induced by interleukin (IL)-1beta plus beta-amyloid [1-42] fragment (A beta) in the human astrocyte cell line, U373MG. The production of IL-6, IL-8, and prostaglandin (PG)E2 was significantly increased by IL-1beta plus A beta (1-42) in a time-dependent manner (P < 0.05). JST significantly inhibited the IL-1beta plus A beta (1-42)-induced IL-6, IL-8, and PGE2 production at 24 h (P < 0.05). Maximal inhibition rate of IL-6, IL-8, and PGE2 production by JST was about 54.40%, 56.01%, and 44.06% respectively. JST (0.01-1 mg/ml) also attenuated the expression of cyclooxygenase (COX)-2 and activation of p38 MAPK induced by IL-1beta and A beta (1-42). These results demonstrated that JST has an anti-inflammatory effect, which might explain its beneficial effect in the treatment of various neurodegenerative diseases such as AD.
Assuntos
Anti-Inflamatórios/farmacologia , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Peptídeos beta-Amiloides/toxicidade , Astrocitoma , Linhagem Celular Tumoral , Ciclo-Oxigenase 2 , Dinoprostona/antagonistas & inibidores , Ativação Enzimática/efeitos dos fármacos , Humanos , Interleucina-1/toxicidade , Interleucina-6/antagonistas & inibidores , Interleucina-8/antagonistas & inibidores , Proteínas de Membrana/antagonistas & inibidores , Fragmentos de Peptídeos/toxicidade , Inibidores de Proteínas Quinases/farmacologiaRESUMO
During the last decade, a growing corpus of evidence has indicated an important role of inflammatory cytokines in the pathogenesis of cerebral lesion following stroke. Recent data suggest that genetics may in turn contribute to modulating the effects of inflammatory cytokines on cerebral infarction (CI). This paper reviews the physiologic characteristics of major inflammatory cytokines and recent research developments related to cell biology and pathobiology in CI. In particular, this review focuses on the genetic aspects of inflammatory cytokines and their implications in CI.
Assuntos
Moléculas de Adesão Celular/genética , Infarto Cerebral/genética , Citocinas/genética , Polimorfismo Genético , Animais , Moléculas de Adesão Celular/imunologia , Infarto Cerebral/etiologia , Infarto Cerebral/imunologia , Citocinas/imunologia , HumanosRESUMO
AIMS/HYPOTHESIS: A patient with (insulin-dependent) diabetes mellitus receives at least one subcutaneous insulin injection a day to maintain low serum glucose concentrations. Since patients' compliance with such dosage regimens is too low, the development of an oral formula is clearly attractive. We present the development of a liquid formula that can be easily dispersed in water to produce particles named "nanocubicles" which efficiently encapsulate insulin. METHODS: Fasted streptozotocin-induced diabetic rats were administered orally with particles encapsulating insulin, and particles without insulin or soluble insulin in water. Groups of rats were also injected soluble insulin in PBS for control. Blood glucose concentration and insulin concentration were measured 1, 2, 3, 4 and 6 h after the administration of the insulin formulas. RESULTS: In vitro experiments show that the particles can be taken up by the Caco-2 cells at a high ratio. The serum glucose concentration was controlled for more than 6 h after oral insulin administration but returned to the basal concentration in 3 h when 1 IU/kg of insulin was injected intravenously. CONCLUSION/INTERPRETATION: Our biocompatible and stable oral insulin formulation is easy to prepare and produces reproducible hypoglycaemic effects, therefore we anticipate clinical acceptance and utilization of this form of insulin therapy.
Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Insulina/administração & dosagem , Administração Oral , Animais , Glicemia/metabolismo , Química Farmacêutica , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Portadores de Fármacos , Humanos , Injeções Subcutâneas , Insulina/sangue , Insulina/uso terapêutico , Cooperação do Paciente , RatosRESUMO
In order to develop convenient and reproducible methods for the identification of ginseng drugs at a DNA level, randomly amplified polymorphic DNA (RAPD) and PCR-restriction fragment length polymorphism (PCR-RFLP) analyses were applied within Panax species. To authenticate Panax ginseng among ginseng populations, RAPD analysis was carried out using a 20 mer-random primer. The similarity coefficients among the DNA of ginseng plants analyzed were low, ranging from 0.197 to 0.491. In addition, by using PCR-RFLP analysis, very different fingerprints were obtained within Korean ginseng plants. These results suggest that these methods are able to authenticate the concerned Panax species. Broader application of this approach to authenticate other morphologically similar medicinal materials is rationalized.
Assuntos
Panax/química , DNA de Plantas/química , DNA de Plantas/genética , Panax/genética , Raízes de Plantas/química , Polimorfismo de Fragmento de Restrição , RNA Ribossômico/química , RNA Ribossômico/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
The relationship between cerebrovascular disease and an insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme (ACE) gene is still being debated. The frequency of the DD genotype of the ACE gene was significantly higher in subjects with than those without cerebral infarction in Japan. The aim of the present study was to assess the relationship between ACE gene polymorphism and the development of cerebral infarction in a population from Korea. We examined its possible role as a risk factor in patients with cerebral infarction. The association between ACE gene polymorphism and cerebral infarction was examined in 106 patients with cerebral infarction and 498 controls without cerebral infarction. Frequencies of the genotypes and alleles of the ACE gene were investigated. The ACE genotype was analyzed by the polymerase chain reaction (PCR). The frequency of D allele was 37.7% in patients and 39.1% in controls (chi2 = 0.128, p = 0.720). The frequencies of the genotypes of the ACE gene were II: 39.6%, ID: 45.3%, and DD: 15.1% in patients, and II: 37.1%, ID: 47.6%, and DD: 15.3% in controls (chi2 = 0.127, p = 0.721). There was no significant difference in the frequency of the DD genotype of the ACE gene, and we did not find any association between ACE polymorphism and cerebral infarction. These results indicate that ACE polymorphism is not a risk factor for the development of cerebral infarction in a Korean population.
Assuntos
Povo Asiático/genética , Infarto Cerebral/genética , Peptidil Dipeptidase A/genética , Polimorfismo Genético , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Infarto Cerebral/etnologia , Feminino , Genótipo , Humanos , Coreia (Geográfico) , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da PolimeraseRESUMO
The short tandem repeats with repeat units ranging from two to several nucleotides became a powerful tool in the field of forensic identification and paternity determination as well as for research in human gene mapping. Allele and genotype frequencies for 9 short tandem repeats including HUMCSF1PO, HUMTH01, HUMPLA2A1, HUMF13A01, HUMCYAR04, HUMLIPOL, HUMHPRTB, HUMCD4, and HUMFABP were determined using PCR and subsequent analysis of the PCR products by denaturing polyacrylamide gel electrophoresis followed by silver-staining. DNA samples were obtained from about 100 Korean people and amplified in a thermocycler adopting glass capillaries rather than traditional tubes. We found that the bovine serum albumin was an essential additive for the capillary PCR, presumably to coat the inner surface of the capillary which may adsorb Taq DNA polymerase. The capillary thermocycler was very effective in reducing the cycling time such that most of the amplification reactions could be finished within 30 min albeit the PCR product was less than that for the tube systems. All loci except HUMHPRTB met the Hardy-Weinberg expectations according to the exact test. The cumulative power of discrimination (PD) was 0.9999998 and the power of exclusion (POE) for the paternity test was a little low, being 0.9873989.
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Frequência do Gene , Repetições de Microssatélites , Alelos , Eletroforese em Gel de Poliacrilamida , Genética Populacional , Genótipo , Humanos , Coreia (Geográfico) , Microquímica , Modelos Genéticos , Reação em Cadeia da Polimerase/métodos , Coloração pela PrataRESUMO
PURPOSE: To investigate the biological functions of protein kinase C delta (PKC delta) in spermatogenesis. MATERIALS AND METHODS: We examined PKC delta transcript in mouse testis by means of in situ hybridization and Northern blotting. RESULTS: In testes of normal mice, signals of PKC delta gene expression were detected specifically at the spermatid stage. The PKC delta gene was weakly expressed in 8-week-old mice and highly expressed by 12 weeks. However, the expression was not detected in testes of germ cell-deficient W/Wv mice even at 12 weeks. CONCLUSIONS: Protein kinase C delta gene expression may be controlled by specific developmental processes and PKC delta may play a role in spermatogenesis.
Assuntos
Isoenzimas/genética , Proteína Quinase C/genética , Espermatozoides/química , Animais , Northern Blotting , Regulação Enzimológica da Expressão Gênica , Hibridização In Situ , Isoenzimas/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína Quinase C/fisiologia , Proteína Quinase C-delta , RNA Mensageiro/análise , Espermatogênese/fisiologia , Testículo/citologia , Transcrição GênicaRESUMO
The role of protein kinase C (PKC) in the induction of nitric oxide (NO) synthesis in murine peritoneal macrophages was examined. Phorbol ester, a PKC activator, had no effect on NO synthesis by itself, whereas IFN-gamma alone had modest activity. When phorbol ester was used in combination with IFN-gamma, there was a marked cooperative induction of NO synthesis in a dose-dependent manner. This increase in NO synthesis was reflected as increased amount of inducible NO synthase (iNOS) mRNA, as determined by Northern blotting. The optimal effect of phorbol ester was shown at 6 h after treatment with IFN-gamma. Phorbol ester also induced the release of NO to the incubation medium by bacillus Calmette-Guerin-infected peritoneal macrophages. Prolonged incubation of cells with phorbol ester, which down-regulates PKC activity, abolished the synergistic cooperative effect on NO production with IFN-gamma. In addition, such PKC inhibitors as staurosporin or polymyxin B reduced NO production induced by IFN-gamma plus phorbol ester. When the cells were treated with both actinomycin D and phorbol ester after IFN-gamma stimulation, more NO was produced and more iNOS mRNA was expressed than in the cells treated with actinomycin D alone. On the basis of these observations, we conclude that PKC might not be directly involved in the expression of NO synthase, but, instead, might be involved in the stabilization of the iNOS mRNA already expressed by the treatment of IFN-gamma.
Assuntos
Interferon gama/administração & dosagem , Macrófagos Peritoneais/metabolismo , Óxido Nítrico/biossíntese , Acetato de Tetradecanoilforbol/administração & dosagem , Alcaloides/farmacologia , Aminoácido Oxirredutases/genética , Animais , Sequência de Bases , Células Cultivadas , Primers do DNA/química , Dactinomicina/farmacologia , Sinergismo Farmacológico , Expressão Gênica/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Infecções por Mycobacterium/imunologia , Mycobacterium bovis , Óxido Nítrico Sintase , Polimixina B/farmacologia , Proteína Quinase C/fisiologia , RNA Mensageiro/metabolismo , Proteínas Recombinantes , EstaurosporinaRESUMO
We have studied the production of nitric oxide (NO) and superoxide by murine peritoneal macrophages during activation. The production of NO was induced by activation of cells with recombinant interferon-gamma (rIFN-gamma) and lipopolysaccharide (LPS). Phorbol 12-myristate 13-acetate (PMA)-induced formation of superoxide also increased during activation. However, NO released by the activated macrophages exerted the inhibitory effect on the superoxide formation in the same cells. This fact is supported by the increased production of superoxide when the cells were treated with NG-monomethyl-L-arginine (NGMMA) in addition to stimulation with rIFN-gamma and LPS. The production of superoxide was also inhibited by treatment with sodium nitroprusside (SPN), which spontaneously released nitric oxide in vitro, and at the same time there was increased adenosine diphosphate (ADP)-ribosylation of 37 kDa proteins of the cytoplasm. The 3-aminobenzamide (3-AB) treatment, which decreased ADP-ribosylation, partially reversed SNP-induced inhibition of superoxide generation in macrophages. The above data provide evidence that NO decreases superoxide formation possibly via ADP-ribosylation.
Assuntos
Ativação de Macrófagos , Macrófagos Peritoneais/metabolismo , Óxido Nítrico/biossíntese , Superóxidos/metabolismo , Difosfato de Adenosina/metabolismo , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Células Cultivadas , Citoplasma , Eletroforese em Gel de Poliacrilamida , Interferon gama/farmacologia , Lipopolissacarídeos/toxicidade , Medições Luminescentes , Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/fisiologia , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Peso Molecular , Mycobacterium bovis , Óxido Nítrico/antagonistas & inibidores , Nitritos/metabolismo , Nitroprussiato/farmacologia , Proteínas Recombinantes , Acetato de Tetradecanoilforbol/farmacologia , ômega-N-MetilargininaRESUMO
The effects of glucocorticoid on the production of nitric oxide (NO) by murine microglial cells were investigated. Stimulation of the cells with lipopolysaccharide (LPS) or phorbol 12-myristate 13-acetate (PMA) after the treatment of recombinant interferon-gamma (rIFN-gamma) resulted in the increased accumulation of nitrite in the medium. Concomitant incubation of the cells with dexamethasone (DEX) markedly inhibited the production of NO in a dose dependent manner. DEX also suppressed both rIFN-gamma and rIFN-gamma plus LPS-induced activity of the enzyme protein kinase C (PKC), a putative regulator of NO synthesis, but had only a modest inhibitory effect on basal activity. In addition, the inhibitory effect of DEX on NO generation was mimicked by the treatment of PKC inhibitors such as staurosporine (STSN) and polymyxin B. Our findings show that glucocorticoids have the potential to modulate central nervous system (CNS) NO production via the inhibition of PKC activity particularly under the conditions of stimulated production of NO, such as inflammatory and demyelinating CNS disorders.