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The massive loss of oligodendrocytes caused by various pathological factors is a basic feature of many demyelinating diseases of the central nervous system (CNS). Based on a variety of studies, it is now well established that impairment of oligodendrocyte precursor cells (OPCs) to differentiate and remyelinate axons is a vital event in the failed treatment of demyelinating diseases. Recent evidence suggests that Foxg1 is essential for the proliferation of certain precursors and inhibits premature neurogenesis during brain development. To date, very little attention has been paid to the role of Foxg1 in the proliferation and differentiation of OPCs in demyelinating diseases of the CNS. Here, for the first time, we examined the effects of Foxg1 on demyelination and remyelination in the brain using a cuprizone (CPZ)-induced mouse model. In this work, 7-week-old Foxg1 conditional knockout and wild-type (WT) mice were fed a diet containing 0.2% CPZ w/w for 5 weeks, after which CPZ was withdrawn to enable remyelination. Our results demonstrated that, compared with WT mice, Foxg1-knockout mice exhibited not only alleviated demyelination but also accelerated remyelination of the demyelinated corpus callosum. Furthermore, we found that Foxg1 knockout decreased the proliferation of OPCs and accelerated their differentiation into mature oligodendrocytes both in vivo and in vitro. Wnt signaling plays a critical role in development and in a variety of diseases. GSK-3β, a key regulatory kinase in the Wnt pathway, regulates the ability of β-catenin to enter nuclei, where it activates the expression of Wnt target genes. We then used SB216763, a selective inhibitor of GSK-3β activity, to further demonstrate the regulatory mechanism by which Foxg1 affects OPCs in vitro. The results showed that SB216763 clearly inhibited the expression of GSK-3β, which abolished the effect of the proliferation and differentiation of OPCs caused by the knockdown of Foxg1. These results suggest that Foxg1 is involved in the proliferation and differentiation of OPCs through the Wnt signaling pathway. The present experimental results are some of the first to suggest that Foxg1 is a new therapeutic target for the treatment of demyelinating diseases of the CNS.
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The Wnt signaling pathway plays key roles in various developmental processes. Wnt5a, which activates the non-canonical pathway, has been shown to be particularly important for axon guidance and outgrowth as well as dendrite morphogenesis. However, the mechanism underlying the regulation of Wnt5a remains unclear. Here, through conditional disruption of Foxg1 in hippocampal progenitors and postmitotic neurons achieved by crossing Foxg1
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Aim To generate the mouse FoxGl overexpression in the specific brain region based on App/psl mice. Methods A FoxGl transgenic mouse line CAG-loxp-stop-loxp-FoxG1-IRES-EGFP was introduced from Southeast University. By crossing B6; 129-5-HT1Btml(CreERT)Cre with this line, we generated a transgenic mouse line Cre; FoxGl. By crossing App/ps1 with this line, combined with tamoxifen induction, FoxG1 was ectopically expressed in the cortex, striatum and hippocampus in app/ ps1 mice. Results The offspring of the mice over expression of FoxGl in the specific brain region of App/ps1 mice were successful in generation. Conclusions FoxG1 overexpression mice in Alzheimer's Disease brain region is obtained by using reasonable gene recombination, providing new model into the mechanism underlying the Alzheimer's disease related with FoxG1.
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@#Objective To summarize the clinical features of children with congenital Rett variant caused by mutation of FOXG1 and provide the reference for the diagnosis and treatment of the disease. Methods The clinical data of a patient diagnosed as congenital Rett syndrome variant type were summarized. The DNA samples of peripheral blood from the patient and her parents were extracted. The targeted high-throughput sequencing technology was used to detect the sequence of targeted genes, which were associated with the symptoms of the child. Genes were then verified by sanger sequencing. Chromosomal microarray analysis was performed to detect chromosome microdeletions and microduplications. Results The child carried the c.506dupG, p.G169Gfs＊ 286 heterozygous mutations on FOXG1 gene, which located in 14q12, and her parents were wild-type. After querying the HGMD, Clinvar and dbSNP databases, we found that it was not reported. This case was clearly diagnosed as congenital Rett syndrome variant type. We confirmed that the mutation locus was a new mutation. Conclusion For cases with congenital Rett variant manifestations, FOXG1 gene mutation examination is recommended, and preventive treatment of partially predictable dysfunction should be carried out.
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This study was aimed to investigate the effect of Forkhead Box G1 (FOXG1) on the epithelial-mesenchymal transition (EMT) of colorectal cancer (CRC) cells and the underlying mechanism. For this purpose, FOXG1 lentiviral interference (shRNA) plasmid and expression plasmid were constructed. Western blotting was used to analyze the expression of FOXG1 protein in five CRC cells, namely RKO, SW480, SW620, LoVo and DLD-1. The shRNA fragment of FOXG1 (shFOXG1) was designed and synthesized. Recombinant plasmids were obtained with the aid of DNA recombination technique. Double digestion and sequencing were used to identify the recombinant plasmids, and then lentivirus packaging, purification and stable transfection were carried out. Additionally, stable CRC cell lines were screened out. The changes of FOXG1 knockdown and overexpression efficiency, E-cadherin, Vimentin, Fibronectin, Snail, Twist mRNA and protein were investigated respectively by Western blotting and qRT-PCR analysis. Furthermore, the changes of cell morphology after knockdown and cell migration ability were evaluated respectively with optical microscopy, scratch test and Transwell assay. FOXG1 had the highest protein expression in RKO and the lowest in DLD-1 among the five CRC cells. Compared with those of the control group, the cell morphology in FOXG1 knockdown RKO group was changed from spindle into round or polygonal shape, cell polarization was enhanced and tight junction assembly was acclerated while cell migration distance was noticeably decreased. Moreover, the number of cells invaded and migrated through chambers was significantly reduced. Among these key factors of EMT, the expression of E-cadherin was increased while the expressions of Vimentin, Fibronectin, Snail and Twist were decreased. The opposite was the case in the overexpressed FOXG1 group. The overexpression of FOXG1 in CRC promoted the invasion and metastasis of CRC cells and played a crucial role in regulating the EMT. Thus, FOXG1 might be a novel therapeutic target in CRC treatment.
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El síndrome de Rett (SR) es un trastorno del neurodesarrollo que afecta casi exclusivamente a niñas y cursa secundariamente con autismo. Es poco frecuente y consta de 5 formas clínicas, una clásica y el resto atípicas que comprometen de manera general la habilidad manual, el lenguaje y la motricidad amplia unida a la aparición de estereotipias y epilepsia precoz. Con el objetivo de actualizar la información sobre SR, se aplicaron los descriptores de búsqueda Síndrome de Rett, genes y «Síndrome de Rett¼, «Rett Syndrome gene¼, «Rett Syndrome¼, «Rett Syndrome gene therapy¼ y «Rett Syndrome review¼. Se investigó en los archivos digitales PubMed, Hinari, SCIELO y Medline, y se consultaron los sitios web OMIM, ORPHANET, GeneMap, Genetests, Proteins y Gene, entre otros. Entre 1.348 artículos se seleccionaron 42, los cuales reportan 3 genes causantes del síndrome: MECP2, CDKL5 y FOXG. El gen MECP2 está mutado en el 80% de los pacientes con SR clásico así como en el 40% de los afectados con alguna de sus formas atípicas. El SR con epilepsia precoz y la variante congénita se deben fundamentalmente a variaciones en los genes CDKL5 y FOXG1 respectivamente. Conclusiones: El diagnóstico del SR se basa en criterios clínicos, sin embargo, los avances en la biología molecular y en la genética en particular han abierto el abanico de posibilidades diagnósticas a las diferentes formas clínicas que antes quedaban sin clasificar, a la vez que el análisis molecular permite confirmar el criterio clínico y aportar información en cuanto al pronóstico del paciente.
Rett syndrome (RS) is a neurodevelopmental disorder that exclusively affects girls, and occurs along with autism. It is very uncommon, and has five distinct forms, one classic and the others atypical, which generally compromise manual skills, language, and mobility, and widely associated with the appearance of stereotypy and early epilepsy. With the aim of updating the information about RS, a search was performed in the computer data bases of PubMed, Hinari, SCIELO and Medline, as well as consulting other web sites including OMIM, ORPHANET, GeneMap, Genetests, Proteins and Gene, using the descriptors "Síndrome de Rett", "genes y Síndrome de Rett", "Rett Syndrome gene", "Rett Syndrome", "Rett Syndrome gene therapy", and "Rett Syndrome review". Of the 1,348 articles found, 42 articles were selected, which reported 3 genes causing the syndrome: MECP2, CDKL5 and FOXG. The MECP2 gene is mutated in 80% of patients with classic RS, as well as in 40% of those affected by any of its atypical forms. RS with early epilepsy and the congenital variant are mainly due to variations in the CDKL5 and FOXG1 genes, respectively. Conclusions: The diagnosis of RS is based on clinical criteria. However, the advances in molecular biology and genetics have opened a wide range of possibilities for diagnosing the different clinical forms that could not be classified before. Molecular analysis can help confirm the clinical criteria and provided information as regards the prognosis of the patient.
Subject(s)
Humans , Female , Rett Syndrome/physiopathology , Stereotypic Movement Disorder/etiology , Epilepsy/etiology , Prognosis , Rett Syndrome/diagnosis , Rett Syndrome/genetics , Protein Serine-Threonine Kinases/genetics , Methyl-CpG-Binding Protein 2/genetics , Forkhead Transcription Factors/genetics , Molecular Biology/methods , Mutation , Nerve Tissue Proteins/geneticsABSTRACT
Objective To observe the effects of ginkgolide B (GB) on mRNA expression of foxgl and proliferation of cells in brain tissue of newborn rats with hypoxic-ischemic brain damage (HIBD).Methods A total of 128 clean 7-day-old healthy SD rats were randomly divided into sham operation group,the model group,the low-GB dose and the high-GB dose treatment groups.Classic Rice method were used to establish HIBD models in the latter 3 groups.Four hours after operation,and GB in dose of 5 mg/kg and 10 mg/kg was given to rats in the low and the high dose treatment groups by intraperitoneal injection postoperatively,once a day for 5 days,while sham operation and model groups were treated with equal physiological saline.All groups were respectively sacrificed on 3 d,7 d,14 d,28 d respectively.Quantitative real-time fluorescent polymerase chain reaction was employed to detect expression of Foxg1 gene.Then the number of 5-bromodeoxyuridine positive cell in subgranular zone was investigated by immunolluorescent stairning.Results The Foxg1 mRNA expression was observed 3 days after HIBD,peaked on 7th day,and then declined gradually; the levels of Foxg1 mRNA in the 2 treatment groups were higher than that of the HIBD group (all P ＜ 0.01) ; The expression of Foxgl at 7 d,14 d,28 d,in high-dose group were higher than those in the low-dose group (all P ＜ 0.01).The number of 5-bromodeoxyuridine positive cell was increased after HIBD,and the levels in the low-and the high-dose treatment groups were all higher than that of the model group (all P ＜ 0.05) ; the number of positive cell in high-dose treatment groups were higher than that in the low-dose treatment groups (P ＜ 0.05).Conclusions GB can promote the expression of Foxg1 gene and improve the proliferation of cells in Brain tissue after HIBD,which shows more significant efficacy in high-dose group than in low-dose group.
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Objective To observe the effect on Foxg1 gene expression in the subgranular zone (SGZ) of cerebral tissue from neonatal rats with hypoxic-ischemic brain damage (HIBD) after transplantation of neural stem cells (NSCs) derived from umbilical cord blood.Methods Mononuclear cells separated from umbilical cord blood by density gradient centrifugation were cultured with orientated induction to differentiate the NSCs.The neuronal phenotype was identified using immunocytochemical methods.A total of 150 Sprague-Dawley rats were randomly divided into a sham-operation group,an HIBD group and an HIBD-NSCs group.Rats in the HIBD group and the HIBD-NSCs group were subject to ligation of the left carotid artery and then kept in a box under 8％ oxygen and 92％ nitrogen for 2.5 hours to establish the HIBD animal model.The artery was separated but not ligated in the sham operation group,which was not subjected to hypoxia.Twenty-four hours after the operation,the cultivated NSCs were transplanted by caudal vein injection into the rats in the HIBD-NSCs group.Rats were then sacrificed on the 3rd,7th,14th,21st and 28th days after the operation.Foxg1 gene expression in the SGZ was examined using in-situ hybridization methods.Results The number of Nestin-positive cells peaked on the 6th day of cultivation and then decreased by the 9th day.The Foxg1 gene was expressed in the SGZs of each group.The expression increased by the 3rd day after surgery in the HIBD and HIBD-NSCs groups,and peaked on 7th day after the operation,then declined gradually.The average expression level of Foxg1 in the HIBD group was significantly lower than that in the HIBD-NSCs group on the 7th day and thereafter.Conclusions Human umbilical cord blood mesenchymal stem cells can be induced and differentiated into neural stem cells.Foxg1 genes can still be present in the SGZ after birth.HIBD can induce the expression of Foxg1 genes.Transplanting NSCs can promote the expression of Foxg1 genes and improve morphological and functional recovery after HIBD,at least in neonatal rats.
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Foxg1 (previously named BF1) is a winged-helix transcription factor with restricted expression pattern in the telencephalic neuroepithelium of the neural tube and in the anterior half of the developing optic vesicle. Previous studies have shown that the targeted disruption of the Foxg1 gene leads to hypoplasia of the cerebral hemispheres with severe defect in the structures of the ventral telencephalon. To further investigate the molecular mechanisms by which Foxg1 plays essential roles during brain development, we have adopted a strategy to isolate genes whose expression changes immediately after introduction of Foxg1 in cultured neural precursor cell line, HiB5. Here, we report that seventeen genes were isolated by ordered differential displays that are up-regulated by over-expression of Foxg1, in cultured neuronal precursor cells. By nucleotide sequence comparison to known genes in the GeneBank database, we find that nine of these clones represent novel genes whose DNA sequences have not been reported. The results suggest that these genes are closely related to developmental regulation of Foxg1.
Subject(s)
Animals , Rats , Base Sequence , Brain , Cell Line , Cerebrum , Clone Cells , Neural Tube , Neurons , Stem Cells , Telencephalon , Transcription FactorsABSTRACT
Forkhead box O-class 1 (FOXO1) is a key regulator of glucose homeostasis, cell-cycle progression, and apoptosis. Its functions are modulated by forkhead box G1 (FOXG1), which acts as a transcriptional repressor with oncogenic potential. Real-time PCR and immunohistochemical staining were performed in 174 primary bladder cancer specimens and 21 normal bladder mucosae to evaluate these genes. FOXO1 and FOXG1 mRNA expression in cancer tissues were higher than in normal mucosae (each P<0.001). FOXO1 mRNA levels were significantly higher in samples of non-progressed patients (P<0.001), but FOXG1 were enhanced in those of progressed patients (P=0.019). On univariate analysis, FOXO1 mRNA expression was significantly associated with grade, stage, recurrence, progression and survival (each P<0.05). On multivariate analysis, increased FOXO1 mRNA expression was associated with both reduced disease progression (odds ratio [OR], 0.367; 95% confidence interval [CI], 0.163-0.826, P=0.015) and enhanced disease-free survival (OR, 3.262; 95% CI, 1.361-7.820, P=0.008). At a median follow-up of 33 months (range 2 to 156), the patients with a high FOXO1 mRNA expression had a significantly prolonged survival (P=0.001). Immunohistochemical findings of FOXO1 were generally concordant with mRNA expression levels. In conclusion, FOXO1 may be a promising marker for predicting progression in human bladder cancers.
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Disease-Free Survival , Forkhead Transcription Factors/analysis , Neoplasm Staging , Nerve Tissue Proteins/analysis , Odds Ratio , Prognosis , RNA, Messenger/metabolism , ROC Curve , Biomarkers, Tumor/analysis , Urinary Bladder Neoplasms/metabolismABSTRACT
Forkhead box O-class 1 (FOXO1) is a key regulator of glucose homeostasis, cell-cycle progression, and apoptosis. Its functions are modulated by forkhead box G1 (FOXG1), which acts as a transcriptional repressor with oncogenic potential. Real-time PCR and immunohistochemical staining were performed in 174 primary bladder cancer specimens and 21 normal bladder mucosae to evaluate these genes. FOXO1 and FOXG1 mRNA expression in cancer tissues were higher than in normal mucosae (each P<0.001). FOXO1 mRNA levels were significantly higher in samples of non-progressed patients (P<0.001), but FOXG1 were enhanced in those of progressed patients (P=0.019). On univariate analysis, FOXO1 mRNA expression was significantly associated with grade, stage, recurrence, progression and survival (each P<0.05). On multivariate analysis, increased FOXO1 mRNA expression was associated with both reduced disease progression (odds ratio [OR], 0.367; 95% confidence interval [CI], 0.163-0.826, P=0.015) and enhanced disease-free survival (OR, 3.262; 95% CI, 1.361-7.820, P=0.008). At a median follow-up of 33 months (range 2 to 156), the patients with a high FOXO1 mRNA expression had a significantly prolonged survival (P=0.001). Immunohistochemical findings of FOXO1 were generally concordant with mRNA expression levels. In conclusion, FOXO1 may be a promising marker for predicting progression in human bladder cancers.