RESUMO
The lack of treatment options for congenital (0.1%) and partial (10%) tooth anomalies highlights the need to develop innovative strategies. Over two decades of dedicated research have led to breakthroughs in the treatment of congenital and acquired tooth loss. We revealed that by inactivating USAG-1, congenital tooth agenesis can be successfully ameliorated during early tooth development and that the inactivation promotes late-stage tooth morphogenesis in double knockout mice. Furthermore, Anti- USAG-1 antibody treatment in mice is effective in tooth regeneration and can be a breakthrough in treating tooth anomalies in humans. With approximately 0.1% of the population suffering from congenital tooth agenesis and 10% of children worldwide suffering from partial tooth loss, early diagnosis will improve outcomes and the quality of life of patients. Understanding the role of pathogenic USAG-1 variants, their interacting gene partners, and their protein functions will help develop critical biomarkers. Advances in next-generation sequencing, mass spectrometry, and imaging technologies will assist in developing companion and predictive biomarkers to help identify patients who will benefit from tooth regeneration.
RESUMO
Uterine sensitization-associated gene-1 (USAG-1) deficiency leads to enhanced bone morphogenetic protein (BMP) signaling, leading to supernumerary teeth formation. Furthermore, antibodies interfering with binding of USAG-1 to BMP, but not lipoprotein receptor-related protein 5/6 (LRP5/6), accelerate tooth development. Since USAG-1 inhibits Wnt and BMP signals, the essential factors for tooth development, via direct binding to BMP and Wnt coreceptor LRP5/6, we hypothesized that USAG-1 plays key regulatory roles in suppressing tooth development. However, the involvement of USAG-1 in various types of congenital tooth agenesis remains unknown. Here, we show that blocking USAG-1 function through USAG-1 knockout or anti-USAG-1 antibody administration relieves congenital tooth agenesis caused by various genetic abnormalities in mice. Our results demonstrate that USAG-1 controls the number of teeth by inhibiting development of potential tooth germs in wild-type or mutant mice missing teeth. Anti-USAG-1 antibody administration is, therefore, a promising approach for tooth regeneration therapy.
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OBJECTIVES: Human papillomavirus (HPV) infection drives carcinogenesis in the oropharynx. No standard sampling or HPV detection methods for evaluating oropharyngeal HPV infection exist. The prevalence of oral HPV infection in Japan is unknown. MATERIALS AND METHODS: We examined 435 healthy Japanese individuals to address whether adding tonsillar washing to oral gargling would improve HPV detection. We compared HPV assessment using GENOSEARCH HPV31 versus nested PCR and direct sequencing. Associations between HPV infection and demographic and behavioral characteristics were examined. RESULTS: Most participants who were HPV-positive based on oral gargles were also HPV-positive based on tonsillar washings: 11 (64.7%) of 17 on nested PCR and 12 (70.6%) of 17 on GENOSEARCH HPV31. Although HPV infection was more prevalent in oral gargles followed by tonsillar washings than in oral gargles alone, the difference was not statistically significant (nested PCR, 4.8% vs. 3.9%, P = 0.46; GENOSEARCH HPV31, 5.3% vs. 3.9%, P = 0.33). The overall agreement between nested PCR and GENOSEARCH HPV31 was 98.6%, with 76.0% positive agreement. The overall prevalence of oral HPV infection in Japan was 5.7% (95% confidence interval, 3.9-8.3%). Men had a significantly higher prevalence of oral HPV infection than women (8.3% vs. 2.6%, P = 0.02). Infection increased with number of lifetime sexual partners (P < 0.001 for trend). CONCLUSION: The oropharynx is probably the major source of HPV-infected cells in oral gargles. Oral gargling could be a standard sampling method for evaluating oropharyngeal HPV infection. GENOSEARCH HPV31 could be an option for oral HPV detection.
Assuntos
Doenças da Boca/epidemiologia , Boca/microbiologia , Antissépticos Bucais/efeitos adversos , Tonsila Palatina/microbiologia , Infecções por Papillomavirus/etiologia , Adulto , Idoso , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/virologia , Prevalência , Inquéritos e Questionários , Adulto JovemRESUMO
While the prevalence of supernumerary teeth (ST) is high in permanent dentition, the etiology of ST in humans remains unclear. However, multiple murine models of ST have elaborated on dated mechanisms traditionally ascribed to ST etiology: one involves the rescue of rudimental teeth, and the second considers the contribution of odontogenic epithelial stem cells. It remains unclear whether these mechanisms of ST formation in mice are applicable to humans. The third dentition is usually regressed apoptotic-that is, the teeth do not completely form in humans. Recently, it was suggested that ST result from the rescue of regression of the third dentition in humans. The present investigation evaluates the proportion of collected general ST cases that evinced a third dentition based on the clinical definition of ST derived from the third dentition. We also investigated the contribution of SOX2-positive odontogenic epithelial stem cells to ST formation in humans. We collected 215 general ST cases from 15,008 patients. We confirmed that the general characteristics of the collected ST cases were similar to the results from previous reports. Of the 215 cases, we narrowed our analysis to the 78 patients who had received a computed tomography scan. The frequency of ST considered to have been derived from the third dentition was 26 out of 78 cases. Evidence of a third dentition was especially apparent in the premolar region, was more common in men, and was more likely among patients with ≥3 ST. SOX2-positive odontogenic epithelial stem cells within the surrounding epithelial cells of developing ST were observed in non-third dentition cases and not in third dentition cases. In conclusion, the third dentition is the main cause of ST in humans. The odontogenic epithelial stem cells may contribute to ST formation in cases not caused by a third dentition.
Assuntos
Dente Pré-Molar , Dentição Permanente , Odontogênese , Dente Supranumerário , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Células Epiteliais/citologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Transcrição SOXB1 , Células-Tronco/citologia , Adulto JovemRESUMO
Tooth agenesis is one of the most common congenital anomalies in humans. However, the etiology of tooth agenesis remains largely unclear, as well as evidence base useful for genetic counseling. Therefore, we estimated the prevalence and sibling recurrence risk, and investigated agenetic patterns systematically. Tooth agenesis was classified into two subtypes: hypodontia (one to five missing teeth) and oligodontia (six or more missing teeth). The prevalence of these two subtypes were 6.8% [95% confidence interval (CI): 6.1-7.7%] and 0.1% (95% CI: 0.04-0.3%), respectively, and sibling recurrence risk of these were 24.5% (95% CI: 13.8-38.3%) and 43.8% (95% CI: 26.4-62.3%), respectively. This result suggests that the severe phenotype, oligodontia, might be mostly transmitted in a dominant fashion. Using a simple statistical modeling approach, our data were found to be consistent with a bilateral symmetry model, meaning that there was equal probability of missing teeth from the right and left sides.
Assuntos
Anodontia/epidemiologia , Anodontia/genética , Epidemiologia Molecular , Adolescente , Adulto , Criança , Demografia , Feminino , Humanos , Japão/epidemiologia , Masculino , Prevalência , Dente , Adulto JovemRESUMO
Cleidocranial dysplasia (CCD) is an autosomal dominant inherited skeletal disease with high penetrance and variable expressivity. Although many mutations in RUNX2/CBFA1, an osteoblast-specific transcription factor, have been identified as causes of CCD, it is unclear whether these mutation genotypes relate to various symptoms. Heterogeneous mutations of RUNX2/CBFA1 result in disease characterized by abnormal skeletal genesis and dental disorders. There are few reports describing the relation between detailed orofacial pathology and the RUNX2/CBFA1 genotype. The case of a Japanese patient with severe orofacial dysplasia who was clinically thought to have CCD is described here. The authors performed mutation analysis on the RUNX2/CBFA1 gene and identified a novel frameshift mutation (722delT), which produces a mutant RUNX2/CBFA1 with a truncating C-terminus distal to the runt domain.
Assuntos
Displasia Cleidocraniana/genética , Códon sem Sentido , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Mutação da Fase de Leitura , Erupção Dentária/genética , Adulto , Povo Asiático/genética , Cefalometria , Análise Mutacional de DNA , Humanos , Japão , Masculino , Maxila/anormalidades , Maxila/diagnóstico por imagem , Estrutura Terciária de Proteína/genética , Radiografia , Retrognatismo/genética , Dente Supranumerário/genéticaRESUMO
BACKGROUND: The relationship between plasma angiopoietin-like protein 3 (ANGPTL3), and lipoprotein lipase (LPL) activity and hepatic triglyceride lipase (HTGL) activity has not been investigated in the metabolism of remnant lipoproteins (RLPs) and high-density lipoprotein (HDL) in human plasma. METHODS: ANGPTL3, LPL activity, HTGL activity, RLP-C and RLP-TG and small, dense LDL-cholesterol (sd LDL-C) were measured in 20 overweight and obese subjects in the fasting and postprandial states. RESULTS: Plasma TG, RLP-C, RLP-TG and sd LDL-C were inversely correlated with LPL activity both in the fasting and postprandial states, but not correlated with HTGL activity and ANGPTL3. However, plasma HDL-C was positively correlated with LPL activity both in the fasting and postprandial states, while inversely correlated with HTGL activity. ANGPTL3 was inversely correlated with HTGL activity both in the fasting and postprandial states, but not correlated with LPL activity. CONCLUSION: HTGL plays a major role in HDL metabolism, but not RLP metabolism. These findings suggest that ANGPTL3 is strongly associated with the inhibition of HTGL activity and regulates HDL metabolism, but not associated with the inhibition of LPL activity for the metabolism of RLPs in human plasma.
Assuntos
Angiopoietinas/sangue , Lipase/sangue , Lipase Lipoproteica/sangue , Fígado/enzimologia , Proteína 3 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina , Jejum/sangue , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial , Triglicerídeos/sangueRESUMO
OFF-center retinal ganglion cells (RGCs) occupy a smaller proportion than ON RGCs when RGCs regenerate axons into a transplanted peripheral nerve. We examined whether the regeneration ability of OFF RGCs in adult cats was promoted when the numbers of regenerating RGCs were increased with brain-derived neurotrophic factor (BDNF)+ciliary neurotrophic factor (CNTF)+forskolin (BCF) or 3,4-dihydro-8-(2-hydroxy-3-isopropylamino)-propoxy-3-nitroxy-2H-1-benzopyran (nipradilol), an anti-glaucoma drug. ON or OFF RGCs were morphologically determined on the basis of their dendritic ramification in the inner plexiform layer using computational analysis. In the normal intact retina the ratio of ON and OFF RGCs (ON/OFF ratio) was 1.25 (55%/44%); whereas, it was 2.61 in regenerating RGCs with saline injection (control) 6 weeks after peripheral nerve transplantation. Estimated numbers of regenerating ON and OFF RGCs were 2149 and 895, respectively. An injection of BCF increased only numbers of ON RGCs into 5766 (2.7-fold to control) but not that of OFF RGCs, n=858. Nipradilol increased both estimated numbers of ON (11,518, 5.4-fold to control) and OFF RGCs (7330, 8.2-fold to control). In the retinas with optic nerve (OpN) transection and intravitreal saline-, BCF- or nipradilol-injection, numbers of ON and OFF RGCs surviving axotomy showed similar trend to that in regenerating RGCs. Thus, nipradilol promoted the survival and regeneration abilities of both of ON and OFF RGCs whereas BCF only did the abilities of ON RGCs. The distribution of tropo-myosin-related kinase B, BDNF receptor, was sparser in the outer two thirds of inner plexiform layer. The lower surviving ability of OFF-RGCs may be attributed in part to the distribution.
Assuntos
Axônios/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Fator Neurotrófico Ciliar/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Propanolaminas/farmacologia , Células Ganglionares da Retina/efeitos dos fármacos , Fatores Etários , Animais , Anti-Hipertensivos/farmacologia , Axônios/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/uso terapêutico , Gatos , Contagem de Células , Forma Celular/efeitos dos fármacos , Forma Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Fator Neurotrófico Ciliar/metabolismo , Fator Neurotrófico Ciliar/uso terapêutico , Subunidade alfa do Receptor do Fator Neutrófico Ciliar/efeitos dos fármacos , Subunidade alfa do Receptor do Fator Neutrófico Ciliar/metabolismo , Dendritos/ultraestrutura , Denervação , Glaucoma/tratamento farmacológico , Sobrevivência de Enxerto/efeitos dos fármacos , Sobrevivência de Enxerto/fisiologia , Regeneração Nervosa/fisiologia , Traumatismos do Nervo Óptico/metabolismo , Traumatismos do Nervo Óptico/fisiopatologia , Receptor trkB/efeitos dos fármacos , Receptor trkB/metabolismo , Recuperação de Função Fisiológica/efeitos dos fármacos , Recuperação de Função Fisiológica/fisiologia , Células Ganglionares da Retina/citologia , Células Ganglionares da Retina/metabolismoRESUMO
The present study investigated the effect of Daikenchuto (DKT) on postoperative intestinal adhesion in rats. We evaluated the effects of DKT, constituent medical herbs and active compounds on talc-induced intestinal adhesion in rats and DKT-induced contractions using isolated guinea pig ileum. DKT significantly prevented adhesion formation, and this action was inhibited by pretreatment with atropine or ruthenium red. The constituent medical herbs, Zanthoxylum Fruit and Maltose Syrup Powder significantly prevented adhesion formation. Moreover, hydroxy sanshool (HS) prevented adhesion formation, and this action was inhibited by pretreatment with ruthenium red. In contrast, DKT-induced contractions were inhibited by tetrodotoxin, atropine, and capsazepine. These results suggested that DKT had a preventive action on postoperative adhesive intestinal obstruction, and that this action was mediated by sensory and cholinergic nerves. Furthermore, HS was found to be one of the active compound of DKT, and its action was mediated by sensory nerves.
Assuntos
Amidas/farmacologia , Obstrução Intestinal/prevenção & controle , Extratos Vegetais/farmacologia , Complicações Pós-Operatórias/prevenção & controle , Amidas/isolamento & purificação , Animais , Modelos Animais de Doenças , Frutas , Cobaias , Íleo/efeitos dos fármacos , Obstrução Intestinal/etiologia , Maltose/farmacologia , Medicina Tradicional do Leste Asiático , Contração Muscular/efeitos dos fármacos , Fenômenos Fisiológicos do Sistema Nervoso , Panax , Ratos , Talco , Aderências Teciduais/etiologia , Aderências Teciduais/prevenção & controle , Zanthoxylum/química , ZingiberaceaeRESUMO
Neurons in the CNS can regenerate their axons in an environment of the peripheral nervous system, but this ability is limited. Here we show that an anti-glaucoma drug, nipradilol, at low concentration led to a four-fold increase in the number of cat retinal ganglion cells regenerating their axons into a transplanted peripheral nerve 4 and 6 weeks after axotomy. Nipradilol also increased the number of three main regenerating retinal ganglion cell types (alpha, beta, not alpha/beta), and enhanced the rate of axonal regeneration of these retinal ganglion cells. Nipradilol is a donor of nitric oxide and an antagonist of alpha-1, beta-1 and -2 adrenoreceptors, and we therefore examined whether one of these pharmacological effects might be more important in promoting axon regeneration. A nitric oxide donor increased the number of regenerating retinal ganglion cells, but not the rate of axonal regeneration. Denitro-nipradilol (nitric oxide-deprived nipradilol) or a nitric oxide scavenger injected before nipradilol increased the number of regenerating retinal ganglion cells but did not promote regeneration rate. Blockade of individual alpha- and beta-adrenoreceptors did not increase the number of regenerating retinal ganglion cells or the rate of regeneration. From these results, it is suggested that nitric oxide plays a crucial role in mediating the effects of nipradilol on axon regeneration and neuroprotection, and the metabolite of nipradilol supports the effects.
Assuntos
Regeneração Nervosa/efeitos dos fármacos , Traumatismos do Nervo Óptico/tratamento farmacológico , Propanolaminas/farmacologia , Células Ganglionares da Retina/efeitos dos fármacos , Células Ganglionares da Retina/fisiologia , Antagonistas Adrenérgicos alfa/farmacologia , Antagonistas Adrenérgicos alfa/uso terapêutico , Animais , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Gatos , Sobrevivência de Enxerto/efeitos dos fármacos , Sobrevivência de Enxerto/fisiologia , Fatores de Crescimento Neural/farmacologia , Fatores de Crescimento Neural/uso terapêutico , Regeneração Nervosa/fisiologia , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Doadores de Óxido Nítrico/farmacologia , Doadores de Óxido Nítrico/uso terapêutico , Nervo Óptico/citologia , Nervo Óptico/efeitos dos fármacos , Nervo Óptico/fisiologia , Nervos Periféricos/transplante , Propanolaminas/uso terapêutico , Receptores Adrenérgicos/efeitos dos fármacos , Receptores Adrenérgicos/metabolismo , Células Ganglionares da Retina/citologiaRESUMO
Some retinal ganglion cells in adult cats survive axotomy for two months and regenerate their axons when a peripheral nerve is transplanted to the transected optic nerve. However, regenerated retinal ganglion cells were fewer than 4% of the total retinal ganglion cell population in the intact retina. The present study examined the effects of intravitreal injections of neurotrophic factors (brain-derived neurotrophic factor, ciliary neurotrophic factor, basic fibroblast growth factor, glial cell-derived neurotrophic factor, neurotrophin 4), first on the survival of axotomized cat retinal ganglion cells within 2 weeks, and then on axonal regeneration of the retinal ganglion cells for 2 months after peripheral nerve transplantation. We tested first enhancement of the survival by one of the factors, and then one or two of them supplemented with forskolin, which increases intracellular cAMP. Single injections of 0.5 microg or 1 microg brain-derived neurotrophic factor, 1 microg ciliary neurotrophic factor, or 1 microg glial cell-derived neurotrophic factor significantly increased total numbers of surviving retinal ganglion cells; 1.6-1.8 times those in control retinas. Identification of retinal ganglion cell types with Lucifer Yellow injections revealed that the increase of surviving beta cells was most conspicuous: 2.5-fold (brain-derived neurotrophic factor) to 3.6-fold (ciliary neurotrophic factor). A combined injection of 1 microg brain-derived neurotrophic factor, 1 microg ciliary neurotrophic factor, and 0.1 mg forskolin resulted in a 4.7-fold increase of surviving beta cells, i.e. 50% survival on day 14. On the axonal regeneration by peripheral nerve transplantation, a combined injection of brain-derived neurotrophic factor, ciliary neurotrophic factor, and forskolin resulted in a 3.4-fold increase of beta cells with regenerated axons. The increase of regenerated beta cells was mainly due to the enhancing effect of neurotrophic factors on their survival, and possibly to a change of retinal ganglion cell properties by cAMP to facilitate their axonal regeneration.
Assuntos
Axônios/efeitos dos fármacos , Colforsina/farmacologia , Fatores de Crescimento Neural/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Células Ganglionares da Retina/efeitos dos fármacos , Animais , Axônios/fisiologia , Axotomia , Gatos , Contagem de Células/métodos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Combinação de Medicamentos , Regeneração Nervosa/fisiologia , Retina/efeitos dos fármacos , Retina/fisiologia , Células Ganglionares da Retina/fisiologia , Corpo Vítreo/efeitos dos fármacos , Corpo Vítreo/fisiologiaRESUMO
Neurocan is one of the major chondroitin sulfate proteoglycans expressed in nervous tissues. The expression of neurocan is developmentally regulated, and full-length neurocan is detected in juvenile brains but not in adult brains. In the present study, we demonstrated by western blot analysis that full-length neurocan transiently appeared in adult rat hippocampus when it was lesioned by kainate-induced seizures. Immunohistochemical studies showed that neurocan was detected mainly around the CA1 region although the seizure resulted in neuronal cell degeneration in both the CA1 and CA3 regions of the hippocampus. Double-labeling for neurocan mRNA and glial fibrillary acidic protein demonstrated that many reactive astrocytes expressed neurocan mRNA. The re-expression of full-length neurocan was also observed in the surgically injured adult rat brain. In contrast, the expression of other nervous tissue chondroitin sulfate proteoglycans, such as phosphacan and neuroglycan C, was not intensified but rather was either reduced in the kainate-lesioned hippocampus or in the surgically injured cerebral cortex. These observations indicate that induction of neurocan expression by reactive astrocytes is a common phenomenon in the repair process of adult brain injury, and therefore, it can be postulated that juvenile-type neurocan plays some roles in brain repair.
Assuntos
Astrócitos/metabolismo , Lesões Encefálicas/metabolismo , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Hipocampo/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Convulsões/metabolismo , Animais , Western Blotting , Proteoglicanas de Sulfatos de Condroitina/genética , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica , Ácido Caínico , Lectinas Tipo C , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/genética , Neurocam , Proteoglicanas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Tirosina Fosfatases Classe 5 Semelhantes a Receptores , Convulsões/induzido quimicamente , Sindecana-3 , Fatores de TempoRESUMO
Oncogene amplification and chromosomal anomalies are found in many solid tumors and are often associated with aggressiveness of cancer. We evaluated the frequency and the role of c-erbB-2 gene amplification, relative increase in c-erbB-2 gene copy number, and gain of chromosome 17 in bladder cancer. A total of 29 bladder cancer specimens were examined using fluorescence in situ hybridization (FISH). Dual labeling hybridization with a directly labeled centromere probe for chromosome 17 together with a probe for the c-erbB-2 locus was performed. c-erbB-2 gene amplification was found in 3.4% (1 of 29) of specimens. Relative increase in c-erbB-2 gene copy number was found in 41.4% (12 of 29) of specimens and was significantly associated with tumor grade (P = 0.044 by Fisher's exact test). Gain of chromosome 17 was identified in 65.5% (19 of 29) of specimens and was significantly associated with tumor grade (P = 0.002 by Fisher's exact test) and tumor stage (P = 0.003 by Fisher's exact test). Our results suggest that c-erbB-2 gene amplification, relative increase in c-erbB-2 gene copy number, and gain of chromosome 17 may play important roles in the development and progression of bladder cancers. Moreover, the use of c-erbB-2 amplification, relative increase in c-erbB-2 gene copy number, and gain of chromosome 17 using FISH, together with tumor grade and stage, may provide a more useful clinical indicator in bladder cancer.
Assuntos
Amplificação de Genes , Receptor ErbB-2/genética , Neoplasias da Bexiga Urinária/genética , Aberrações Cromossômicas , Cromossomos Humanos Par 17/genética , Dosagem de Genes , Humanos , Hibridização in Situ Fluorescente , Neoplasias da Bexiga Urinária/patologiaAssuntos
Hipertrigliceridemia , Guias de Prática Clínica como Assunto , Doença Aguda , Arteriosclerose/etiologia , Arteriosclerose/prevenção & controle , Quilomícrons/metabolismo , Humanos , Hipertrigliceridemia/sangue , Hipertrigliceridemia/terapia , Lipoproteínas VLDL/metabolismo , Pancreatite/prevenção & controle , Fatores de RiscoRESUMO
Gene therapy for hypertension is very important for the next generation of antihypertensive drugs. Important question regarding vector-related limitations and suboptimal in vivo delivery systems will require expeditious attention for gene therapy to become a more widely applicable option in cardiovascular diseases including hypertension. However, the elucidation of molecular mechanisms of transcriptional activation of several important genes in the cardiovascular physiology enables us to develop clinical application of gene therapy for hypertension at the level of transcription factors. Recent studies showed that in vivo or ex vivo transfection of double-stranded oligodeoxynucleotides to block the binding of nuclear factors to specific cis-elements in the promoter regions of several genes resulted in inhibition of gene trans-activation and suppressed pathological changes in the cardiovascular system.
Assuntos
Proteínas de Transporte , Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Terapia Genética , Hipertensão/terapia , Angiotensinogênio/genética , Animais , Fatores de Transcrição E2F , Técnicas de Transferência de Genes , Terapia Genética/métodos , Humanos , Hipertensão/genética , Oligodesoxirribonucleotídeos/genética , Regiões Promotoras Genéticas/genética , Proteína 1 de Ligação ao Retinoblastoma , Fator de Transcrição DP1 , Fatores de Transcrição/uso terapêutico , Ativação Transcricional , TransfecçãoRESUMO
In this report, we investigated whether reactive astrocytes produce neuregulins (glial growth factor 2/heregulin/acetylcholine receptor-inducing activity or neu differentiation factor) and its putative receptors, ErbB2 and ErbB3 tyrosine kinases, in the injured CNS in vivo. Significant immunoreactivities with anti-neuregulin, anti-ErbB2, and anti-ErbB3 antibodies were detected on astrocytes at the injured site 4 d after injury to the adult rat cerebral cortex. To elucidate the mechanisms for the upregulation of neuregulin expression in astrocytes, primary cultured astrocytes were treated with certain reagents, including forskolin, that are known to elevate the intracellular level of cAMP and induce marked morphological changes in astrocytes. Western blot analysis showed that the expression of a 52 kDa membrane-spanning form of a neuregulin protein was enhanced in cultured astrocytes after administration of forskolin. The upregulation of glial fibrillary acidic protein was also observed in astrocytes treated with forskolin. In contrast, inactivation of protein kinase C because of chronic treatment with phorbol ester 12-O-tetradecanoyl phorbol 13-acetate downregulated the expression of the 52 kDa isoform, although other splice variants with apparent molecular sizes of 65 and 60 kDa were upregulated. These results suggest that the enhancement of neuregulin expression at injured sites is induced, at least in part, by elevation in intracellular cAMP levels and/or a protein kinase C signaling pathway. The neuregulin expressed on reactive astrocytes may stimulate their proliferation and support the survival of neurons surrounding cortical brain wounds in vivo.
Assuntos
Astrócitos/metabolismo , Lesões Encefálicas/metabolismo , Córtex Cerebral/metabolismo , Neurregulinas/metabolismo , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Lesões Encefálicas/patologia , Células CHO , Células Cultivadas , Córtex Cerebral/patologia , Colforsina/farmacologia , Cricetinae , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Modelos Animais de Doenças , Proteína Glial Fibrilar Ácida/metabolismo , Traumatismos Cranianos Penetrantes/metabolismo , Traumatismos Cranianos Penetrantes/patologia , Neurregulinas/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteína Quinase C/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor ErbB-2/metabolismo , Receptor ErbB-3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Acetato de Tetradecanoilforbol , Regulação para CimaRESUMO
Fibronectin plays an important role in vascular remodeling. A functional interaction between mechanical stimuli and locally produced vasoactive agents is suggested to be crucial for vascular remodeling. We examined the effect of mechanical stretch on fibronectin gene expression in vascular smooth muscle cells and the role of vascular angiotensin II in the regulation of the fibronectin gene in response to stretch. Cyclic stretch induced an increase in vascular fibronectin mRNA levels that was inhibited by actinomycin D and CV11974, an angiotensin II type 1 receptor antagonist; cycloheximide and PD123319, an angiotensin II type 2 receptor antagonist, did not affect the induction. In transfection experiments, fibronectin promoter activity was stimulated by stretch and inhibited by CV11974 but not by PD123319. DNA-protein binding experiments revealed that cyclic stretch enhanced nuclear binding to the AP-1 site, which was partially supershifted by antibody to c-Jun. Site-directed mutation of the AP-1 site significantly decreased the cyclic stretch-mediated activation of fibronectin promoter. Furthermore, antisense c-jun oligonucleotides decreased the stretch-induced stimulation of the fibronectin promoter activity and the mRNA expression. These results suggest that cyclic stretch stimulates vascular fibronectin gene expression mainly via the activation of AP-1 through the angiotensin II type 1 receptor.
Assuntos
Fibronectinas/genética , Regulação da Expressão Gênica , Músculo Liso Vascular/metabolismo , Angiotensina II/metabolismo , Sequência de Bases , Células Cultivadas , Primers do DNA , Dactinomicina/farmacologia , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Regiões Promotoras Genéticas , Inibidores da Síntese de Proteínas/farmacologia , RNA Mensageiro/genética , Receptores de Angiotensina/metabolismo , Sistema Renina-Angiotensina/genética , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica , Ativação TranscricionalRESUMO
The effects of glycosaminoglycans (GAG) on cell-to-substratum adhesion and neurite elongation were examined in primary cultures of fetal rat hippocampal neurons using tissue culture dishes coated with GAGs coupled to dipalmitoylphosphatidylethanolamine (PE), a novel probe for biological functions of GAGs. Both chondroitin sulfate conjugate to PE (CS-PE) and hyaluronic acid conjugate to PE (HA-PE) promoted neurite elongation from neurons in a dose-dependent manner when immobilized onto polylysine-coated dishes at various concentrations up to 1.0 microg/ml. The coating of CS-PE or HA-PE at a concentration higher than 1.0 microg/ml resulted in failure of neurite extension and adhesion of neurons to the substrata. In contrast, heparin conjugate to PE (HP-PE) did not exert any effects on neurite elongation or on cell attachment at these concentrations. These findings suggest that GAGs serve as a modulator for neurite elongation during neuronal network formation in the developing central nervous system.
Assuntos
Glicosaminoglicanos/farmacologia , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Animais , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Sulfatos de Condroitina , Feto/citologia , Glicosaminoglicanos/química , Ácido Hialurônico , Estrutura Molecular , Neuritos/efeitos dos fármacos , Neuritos/ultraestrutura , Fosfatidiletanolaminas , RatosRESUMO
BACKGROUND AND OBJECTIVE: The purpose of the present study was to assess whether "scan irradiation" with a pulsed Nd:YAG laser could produce changes in intrapulpal nerve activities and pulpal blood flow and to investigate whether it would cause tissue damage in the pulp. STUDY DESIGN/MATERIALS AND METHODS: The pulsed Nd:YAG laser was used to irradiate, in a scanning manner, the canine tooth pulp in sodium pentobarbitone anesthetized cats. The compound action potentials and spike response in the functional single afferent nerve fibers were recorded while responding to various external stimuli applied to the exposed dentin. Histologic observation was performed to detect lasing-induced tissue changes. RESULTS: Pulpal compound action potentials evoked by various external stimuli were significantly reduced (P < 0.05) and unit firings were observed in both functional single A delta- and C-fibers during irradiation. Unit responses to external mechanical stimulation of the dentin completely disappeared after "scan irradiation" with the pulsed Nd:YAG laser. Histologic observation revealed that irradiation with the laser produced tissue damage in the pulp. CONCLUSION: "Scan irradiation" with the pulsed Nd:YAG laser of cat's teeth produced alterations in the intrapulpal nerve activities, as well as caused tissue damage in the pulp.