RESUMO
A number of homeobox genes are implicated in the malignancy of various cancers. Here, we investigated the role of the homeobox gene SIX4 in non-small-cell lung cancer (NSCLC). The sine oculis homeobox (SIX4) gene was found to be highly expressed at both mRNA and protein levels in NSCLC tumor tissues as compared with matching normal counterparts. In this study, the SIX4 gene of two human NSCLC cell lines (A549 and PC9) was overexpressed or silenced using the lentiviral system. We evaluated the malignancy-associated phenotype of transfected cells, which demonstrated that exogenous expression of the SIX4 gene greatly enhanced the proliferation, migration, and invasion of NSCLC cells. The opposite was true in the SIX4-silenced cells. Transcriptomic profiling analysis revealed that the SIX4 gene modulated the expression of hundreds of downstream target genes in a cell context-dependent manner. Most notably, the SIX4 gene controls the expression of crucial genes with evidently oncogenic function. We conclude that SIX4 plays an oncogenic role and may be potentially utilized as a diagnostic and therapeutic marker for NSCLC.
Assuntos
Carcinogênese/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/genética , Neoplasias Pulmonares/genética , Proteínas de Neoplasias/genética , Transativadores/genética , Células A549 , Carcinogênese/metabolismo , Carcinogênese/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Perfilação da Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Proteínas de Homeodomínio/agonistas , Proteínas de Homeodomínio/antagonistas & inibidores , Proteínas de Homeodomínio/metabolismo , Humanos , Lentivirus/genética , Lentivirus/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Proteínas de Neoplasias/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Transativadores/agonistas , Transativadores/antagonistas & inibidores , Transativadores/metabolismoRESUMO
This study aimed to investigate the potential roles of TG-interacting factor (TGIF) in benzo(a)pyrene (BaP)-induced migration, invasion, and metastasis of lung adenocarcinoma cells. Cells were treated with different concentrations of BaP. MTT assays were used to measure cell proliferation. Quantitative real-time polymerase chain reaction (qRT-PCR) and immunoblots were applied to measure the TGIF expression. A dual-luciferase reporter gene assay was performed to assess the effects of BaP on TGIF promoter-driven reporter gene expression. Wound-healing, transwell, and tail vein metastasis assays were performed to evaluate migratory, invasive, and metastatic capacity. Our results showed that BaP treatment increased the expression of TGIF mRNA and protein. Additionally, BaP treatment enhanced TGIF promoter-driven reporter gene expression. We observed that BaP treatment promoted the migration, invasion, and metastasis of H157 cells, which could be blocked by silencing TGIF. The expression of TGIF mRNA was significantly higher in metastatic lung adenocarcinoma samples than in non-metastatic lung adenocarcinoma samples, and higher levels of TGIF mRNA expression were observed in metastatic lung adenocarcinoma samples from patients with a smoking history than in those from patients with a non-smoking history. Our findings suggest that BaP treatment promotes the migration, invasion, and metastasis of human lung adenocarcinoma cells by upregulating TGIF.
Assuntos
Adenocarcinoma/induzido quimicamente , Benzo(a)pireno/toxicidade , Carcinógenos/toxicidade , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Homeodomínio/agonistas , Neoplasias Pulmonares/induzido quimicamente , Regiões Promotoras Genéticas/efeitos dos fármacos , Proteínas Repressoras/agonistas , Regulação para Cima/efeitos dos fármacos , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Adenocarcinoma de Pulmão , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Genes Reporter/efeitos dos fármacos , Proteínas de Homeodomínio/antagonistas & inibidores , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Proteínas de Neoplasias/agonistas , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Transplante de Neoplasias , Interferência de RNA , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fumar/efeitos adversos , Carga Tumoral/efeitos dos fármacosRESUMO
Cancer recurrence, which is frequently accompanied by chemotherapy, has been a challenge in cancer treatment. This study was carried out to examine the potential applications of the reactive oxygen species (ROS)-producing cold atmospheric plasma (CAP) to overcome the cancer cells' drug resistance, which has been emerging as an alternative therapeutic tool for cancer. For this, we developed a tamoxifen (Tam)-resistant MCF-7 (MCF-7/TamR) breast cancer cell model and examined the effect of CAP on the recovery of Tam sensitivity at the cellular and molecular level. The ROS level was increased 1.9-fold in CAP-treated MCF-7/TamR cells compared to the non-treated cell. CAP was proven to restore sensitivity by up to 50% for MCF-7/TamR cells against Tam after CAP treatment. The comparison of genome-wide expression between the acquisition of Tam resistance and CAP treatment identified 20 genes that commonly showed significant expression changes. Notably, all the genes except two have been oppositely dysregulated in the two cellular statuses, and the majority of them are known to contribute to the acquisition of Tam resistance. The protein expression of selected genes, MX1 and HOXC6, was recovered to that of their parental cell by CAP. Furthermore, the dysregulation of MX1 and HOXC6 in MCF-7/TamR alleviated the drug sensitivity recovery effect of CAP. Taken together, CAP inhibited the growth of Tam-resistant MCF-7 cancer cells and reset it to the Tam-sensitive status by restoring the expression of drug resistance-related genes. These findings may lend credence to CAP as an alternative or complementary tool in the treatment or prevention of Tam-resistant cancer.
Assuntos
Antineoplásicos Hormonais/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Gases em Plasma/farmacologia , Tamoxifeno/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/efeitos dos fármacos , Estudo de Associação Genômica Ampla , Proteínas de Homeodomínio/agonistas , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Células MCF-7 , Proteínas de Resistência a Myxovirus/agonistas , Proteínas de Resistência a Myxovirus/genética , Proteínas de Resistência a Myxovirus/metabolismo , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/metabolismo , Transdução de SinaisRESUMO
Bone homeostasis is maintained by balancing bone formation and bone resorption, but an imbalance between them is associated with various bone-related diseases such as osteoporosis and rheumatoid arthritis. We found that 5,6-dehydrokawain (DK) and dihydro-5,6-dehydrokawain (DDK), which were isolated as promising compounds from Alpinia zerumbet rhizomes, promote differentiation of osteoblastic MC3T3-E1 cells. DK and DDK increased the alkaline phosphatase activity and matrix mineralization of MC3T3-E1 cells. DK exerts larger effects than DDK. The gene expression of runt-related transcription factor 2 and osterix, which are essential transcription factors in the early period of osteoblast differentiation, was significantly increased by DK treatment. The mRNA level of distal-less homeobox 5 was also enhanced by DK treatment, and DK activated the p38 mitogen-activated protein kinase pathway. Therefore, DK may have clinical potential for preventing osteoporosis, and could be considered as a potential anabolic therapeutic agent.
Assuntos
Alpinia/química , Diferenciação Celular/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Pironas/farmacologia , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Subunidade alfa 1 de Fator de Ligação ao Core/agonistas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Regulação da Expressão Gênica , Proteínas de Homeodomínio/agonistas , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteogênese/genética , Extratos Vegetais/química , Pironas/isolamento & purificação , RNA Mensageiro/agonistas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Rizoma/química , Fator de Transcrição Sp7 , Fatores de Transcrição/agonistas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
A physio-pathological feature of diabetes mellitus is a significant reduction of ß-pancreatic cells. The growth, differentiation and function maintenance of these cells is directed by transcription factors. Nkx6.1 is a key transcription factor for the differentiation, neogenesis and maintenance of ß-pancreatic cells. We reported that silymarin restores normal morphology and endocrine function of damaged pancreatic tissue after alloxan-induced diabetes mellitus in rats. The aim of this study was to analyze the effect of silymarin on Nkx6.1 transcription factor expression and its consequence in ß cells neogenesis. Sixty male Wistar rats were partially pancreatectomized and divided into twelve groups. Six groups were treated with silymarin (200 mg/Kg p.o) for periods of 3, 7, 14, 21, 42 and 63 days. Additionally, an unpancreatectomized control group was used. Nkx6.1 and insulin gene expression were assessed by RT-PCR assay in total pancreatic RNA. ß-Cell neogenesis was determined by immunoperoxidase assay. Silymarin treated group showed an increase of Nkx6.1 and insulin genic expression. In this group, there was an increment of ß-cell neogenesis in comparison to pancreatectomized untreated group. Silymarin treatment produced a rise in serum insulin and serum glucose normalization. These results suggest that silymarin may improve the reduction of ß pancreatic cells observed in diabetes mellitus.
Assuntos
Proteínas de Homeodomínio/agonistas , Células Secretoras de Insulina/efeitos dos fármacos , Insulina/agonistas , Pancreatectomia , Substâncias Protetoras/farmacologia , Silimarina/farmacologia , Animais , Glicemia/metabolismo , Contagem de Células , Proliferação de Células , Diabetes Mellitus , Modelos Animais de Doenças , Expressão Gênica , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Técnicas Imunoenzimáticas , Insulina/genética , Insulina/metabolismo , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Masculino , Ratos , Ratos WistarRESUMO
AIMS/HYPOTHESIS: Incretin therapies, which are used to treat diabetic patients, cause a chronic supra-physiological increase in GLP-1 circulating levels. It is still unclear how the resulting high hormone concentrations may affect pancreatic alpha cells. The present study was designed to investigate the effects of chronic exposure to high GLP-1 levels on a cultured pancreatic alpha cell line. METHODS: α-TC1-6 cell line was cultured in the presence or absence of GLP-1 (100 nmol/l) for up to 72 h. In our model GLP-1 receptor (GLP-1R) was measured. After the cells were exposed to GLP-1 the levels of glucagon secretion were measured. Because GLP-1 acts on intracellular cAMP production, the function of GLP-1R was studied. We also investigated the effects of chronic GLP-1 exposure on the cAMP/MAPK pathway, Pax6 levels, the expression of prohormone convertases (PCs), glucagon gene (Gcg) and protein expression, glucagon and GLP-1 production. RESULTS: In our model, we were able to detect GLP-1R. After GLP-1 exposure we found a reduction in glucagon secretion. During further investigation of the function of GLP-1R, we found an activation of the cAMP/MAPK/Pax6 pathway and an increase of Gcg gene and protein expression. Furthermore we observed a significant increase in PC1/3 protein expression, GLP-1 intracellular content and GLP-1 secretion. CONCLUSIONS/INTERPRETATION: Our data indicate that the chronic exposure of pancreatic alpha cells to GLP-1 increases the ability of these cells to produce and release GLP-1. This phenomenon occurs through the stimulation of the transcription factor Pax6 and the increased expression of the protein convertase PC1/3.
Assuntos
Proteínas do Olho/genética , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Células Secretoras de Glucagon/efeitos dos fármacos , Proteínas de Homeodomínio/genética , Fatores de Transcrição Box Pareados/genética , Pró-Proteína Convertase 1/genética , Proteínas Repressoras/genética , Linhagem Celular Tumoral , AMP Cíclico/metabolismo , Proteínas do Olho/agonistas , Proteínas do Olho/metabolismo , Regulação da Expressão Gênica , Peptídeo 1 Semelhante ao Glucagon/biossíntese , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1 , Células Secretoras de Glucagon/citologia , Células Secretoras de Glucagon/metabolismo , Proteínas de Homeodomínio/agonistas , Proteínas de Homeodomínio/metabolismo , Humanos , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fator de Transcrição PAX6 , Fatores de Transcrição Box Pareados/agonistas , Fatores de Transcrição Box Pareados/metabolismo , Pró-Proteína Convertase 1/metabolismo , Receptores de Glucagon/genética , Receptores de Glucagon/metabolismo , Proteínas Repressoras/agonistas , Proteínas Repressoras/metabolismo , Transdução de SinaisRESUMO
Cardiac fibrosis is linked to fibroblast-to-myofibroblast phenoconversion and proliferation but the mechanisms underlying this are poorly understood. Ski is a negative regulator of TGF-ß-Smad signaling in myofibroblasts, and might redirect the myofibroblast phenotype back to fibroblasts. Meox2 could alter TGF-ß-mediated cellular processes and is repressed by Zeb2. Here, we investigated whether Ski diminishes the myofibroblast phenotype by de-repressing Meox2 expression and function through repression of Zeb2 expression. We show that expression of Meox1 and Meox2 mRNA and Meox2 protein is reduced during phenoconversion of fibroblasts to myofibroblasts. Overexpression of Meox2 shifts the myofibroblasts into fibroblasts, whereas the Meox2 DNA-binding mutant has no effect on myofibroblast phenotype. Overexpression of Ski partially restores Meox2 mRNA expression levels to those in cardiac fibroblasts. Expression of Zeb2 increased during phenoconversion and Ski overexpression reduces Zeb2 expression in first-passage myofibroblasts. Furthermore, expression of Meox2 is decreased in scar following myocardial infarction, whereas Zeb2 protein expression increases in the infarct scar. Thus Ski modulates the cardiac myofibroblast phenotype and function through suppression of Zeb2 by upregulating the expression of Meox2. This cascade might regulate cardiac myofibroblast phenotype and presents therapeutic options for treatment of cardiac fibrosis.
Assuntos
Fibroblastos/metabolismo , Proteínas de Homeodomínio/metabolismo , Proteínas Musculares/metabolismo , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Miofibroblastos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Animais , Diferenciação Celular , Fibroblastos/patologia , Fibrose , Regulação da Expressão Gênica , Proteínas de Homeodomínio/agonistas , Proteínas de Homeodomínio/antagonistas & inibidores , Proteínas de Homeodomínio/genética , Proteínas Musculares/agonistas , Proteínas Musculares/genética , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Miocárdio/patologia , Miofibroblastos/patologia , Fenótipo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Transdução de Sinais , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Homeobox 2 de Ligação a E-box com Dedos de Zinco , Homeobox 1 de Ligação a E-box em Dedo de ZincoRESUMO
Bone marrow stromal cells (BMSCs) play critical roles in repairing endothelium damage. However, the mechanisms underlying BMSC differentiation into vascular endothelial cells (VECs) is not well understood. We aimed to find new factors involved in this process by exploiting a novel chemical inducer in a gene microarray assay. We first identified a novel benzoxazine derivative (6-amino-2,3-dihydro-3-hydroxymethyl-1,4-benzoxazine; ABO) that can induce BMSC differentiation to VECs in a capillary-like tube formation assay, promote analysis of endothelial cell-specific marker expression, and facilitate uptake of 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate-acetylated low-density lipoprotein (Dil-Ac-LDL). Microarray analysis of BMSCs treated with ABO for 4 h revealed changes in only a handful of genes. The only one upregulated was homeobox-containing 1 (Hmbox1) gene, whereas six genes, including IP-10 and others, were downregulated. The upregulation of Hmbox1 and downregulation of IP-10 were confirmed by RT-PCR, quantitative PCR (qPCR), and Western blot analysis. It is reported that IP-10 could suppresse EC differentiation into capillary structures. In this study ABO could not induce BMSC differentiation to VECs in the presence of IP-10. Small interfering RNA knockdown of Hmbox1 blocked ABO-induced BMSC differentiation and increased the level of IP-10 but decreased Ets-1. Thus, ABO is a novel inducer for BMSC differentiation to VECs, and Hmbox1 is a key factor in the differentiation. IP-10 and Ets-1 might be relevant targets of Hmbox1 in BMSC differentiation to VECs. These findings provide information on a novel target and a new platform for further investigating the gene control of BMSC differentiation to VECs.
Assuntos
Benzoxazinas/farmacologia , Células da Medula Óssea/citologia , Diferenciação Celular/fisiologia , Endotélio Vascular/citologia , Proteínas de Homeodomínio/fisiologia , Neovascularização Fisiológica/fisiologia , Animais , Células da Medula Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Células Cultivadas , Endotélio Vascular/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Homeodomínio/agonistas , Proteínas de Homeodomínio/genética , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , Neovascularização Fisiológica/genética , Análise de Sequência com Séries de Oligonucleotídeos , Ratos , Ratos Wistar , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Células Estromais/fisiologiaRESUMO
Agents inducing O(6)-methylguanine (O(6)MeG) in DNA such as N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) are cytotoxic and a deficiency in mismatch repair (MMR) results in lack of sensitivity to this genotoxin (termed alkylation tolerance). Here, we show that ING2, a member of the inhibitor of growth family, is required for cell death induced by MNNG. We further observe that MNNG treatment increases cellular protein levels of ING2 that is dependent on intact MMR function and that MNNG-induced ING2 localizes and associates with p73alpha in the nucleus. Suppression of ING2 by short hairpin RNA (shRNA) in MMR-proficient colorectal cancer cells decreased its sensitivity to MNNG and, in addition, abrogated MNNG-induced stabilization and acetylation of p73alpha. Interestingly, suppression of p73alpha had a greater impact on MNNG-induced cell death than ING2 leading us to conclude that ING2 regulates the cell death response, in part, through p73alpha. Inhibition of c-Abl by STI571 or suppression of c-Abl expression by shRNA blocked ING2 induction and p73alpha acetylation induced by this alkylator. Similarly, suppression of MMR (MLH1) by shRNA abrogated ING2 induction/p73alpha acetylation. Taken together, these results demonstrate that MLH1/c-Abl-dependent activation of ING2>p73alpha signaling regulates cell death triggered by MNNG and further suggests that dysregulation of this event may, in part, be responsible for alkylation tolerance observed in MMR compromised cells.
Assuntos
Alquilantes/toxicidade , Apoptose , Carcinógenos/toxicidade , Reparo de Erro de Pareamento de DNA , Proteínas de Ligação a DNA/metabolismo , Proteínas de Homeodomínio/metabolismo , Metilnitronitrosoguanidina/toxicidade , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas c-abl/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antineoplásicos/farmacologia , Benzamidas , Proteínas de Ligação a DNA/antagonistas & inibidores , Células HeLa , Proteínas de Homeodomínio/agonistas , Humanos , Mesilato de Imatinib , Proteína 1 Homóloga a MutL , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/efeitos dos fármacos , Oligonucleotídeos/metabolismo , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-abl/efeitos dos fármacos , Pirimidinas/farmacologia , RNA Interferente Pequeno/metabolismo , Receptores Citoplasmáticos e Nucleares/agonistas , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Transfecção , Proteína Tumoral p73 , Proteína Supressora de Tumor p53/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/agonistas , Proteínas Supressoras de Tumor/antagonistas & inibidoresRESUMO
INTRODUCTION: Prenatal alcohol exposure via maternal liquid diet consumption by C57BL/6 (B6) mice causes conspicuous midline neural tube deficit (dysraphia) and disruption of genesis and development of serotonin (5-HT) neurons in the raphe nuclei, together with brain growth retardation. The current study tested the hypothesis that concurrent treatment with either an activity-dependent neurotrophic factor (ADNF) agonist peptide [SALLRSIPA, (SAL)] or an activity-dependent neurotrophic protein (ADNP) agonist peptide [NAPVSIPQ, (NAP)] would protect against these alcohol-induced deficits in brain development. METHODS: Timed-pregnant B6 dams consumed alcohol from embryonic day 7 (E7, before the onset of neurulation) until E15. Fetuses were obtained on E15 and brain sections processed for 5-HT immunocytochemistry, for evaluation of morphologic development of the brainstem raphe and its 5-HT neurons. Additional groups were treated either with SAL or NAP daily from E7 to E15 to assess the potential protective effects of these peptides. Measures of incomplete occlusion of the ventral canal and the frequency and extent of the openings in the rhombencephalon were obtained to assess fetal dysraphia. Counts of 5-HT-immunostained neurons were also obtained in the rostral and caudal raphe. RESULTS: Prenatal alcohol exposure resulted in abnormal openings along the midline and delayed closure of ventral canal in the brainstem. This dysraphia was associated with reductions in the number of 5-HT neurons both in the rostral raphe nuclei (that gives rise to ascending 5-HT projections) and in the caudal raphe (that gives rise to the descending 5-HT projections). Concurrent treatment of the alcohol-consuming dams with SAL prevented dysraphia and protected against the alcohol-induced reductions in 5-HT neurons in both the rostral and caudal raphe. NAP was less effective in protecting against dysraphia and did not protect against 5-HT loss in the rostral raphe, but did protect against loss in the caudal raphe. CONCLUSIONS: These findings further support the potential usefulness of these peptides for therapeutic interventions in pregnancies at risk for alcohol-induced developmental deficits. Notably, the ascending 5-HT projections of the rostral raphe have profound effects in regulating forebrain development and function, and the descending 5-HT projections of the caudal raphe are critical for regulating respiration. Protection of the rostral 5-HT-system may help prevent structural and functional deficits linked to abnormal forebrain development, and protection of the caudal systems may also reduce the increased risk for sudden infant death syndrome associated with prenatal alcohol exposure.
Assuntos
Depressores do Sistema Nervoso Central/efeitos adversos , Etanol/efeitos adversos , Proteínas de Homeodomínio/agonistas , Proteínas do Tecido Nervoso/agonistas , Defeitos do Tubo Neural/prevenção & controle , Fragmentos de Peptídeos/uso terapêutico , Animais , Tronco Encefálico/efeitos dos fármacos , Tronco Encefálico/metabolismo , Depressores do Sistema Nervoso Central/farmacologia , Modelos Animais de Doenças , Etanol/farmacologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Degeneração Neural/induzido quimicamente , Degeneração Neural/prevenção & controle , Defeitos do Tubo Neural/induzido quimicamente , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neuropeptídeos , Oligopeptídeos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Lesões Pré-Natais/induzido quimicamente , Lesões Pré-Natais/prevenção & controle , Respiração/efeitos dos fármacos , Serotonina/metabolismo , Disrafismo Espinal/induzido quimicamente , Disrafismo Espinal/prevenção & controleRESUMO
We report the identification of substituted cis-bicyclo[3.3.0]-oct-2-enes as small molecule agonists of subfamily V orphan nuclear receptors (NR5A), liver receptor homolog-1 (LRH-1) and steroidogenic factor-1 (SF-1). Using fluorescence resonance energy transfer (FRET)-based biochemical assays, compound 5a (GSK8470) was identified as a high-affinity ligand for LRH-1 and SF-1. In liver cells, 5a increased the expression of the LRH-1 target gene small heterodimer partner (SHP). Synthesis of analogues modified at three positions led to the development of compounds with functional selectivity between LRH-1 and SF-1.