关键词： 尿道下裂   转录激活因子3   结缔组织生长因子   17-β乙炔雌二醇  

摘要： 目的:雌激素与尿道下裂的发生关系密切,本研究旨在比较尿道下裂患儿包皮和同龄正常儿童包皮中转录激活因子3(ATF3)和结缔组织生长因子(CTGF)的表达,明确二者与尿道下裂的关系,探寻雌激素引起尿道下裂的分子机制。方法:从包皮中分离成纤维细胞并原代培养,用不同浓度(1.0μmol/L、0.1μmol/L、10.0nmol/L、1.0nmol/L、0.1nmol/L)的17-β乙炔雌二醇(17-EE)处理2h,或选择0.1μmol/L的17-EE处理不同时间(0.5、1、2、4、8、16、24h),观察17-EE对ATF3和CTGF表达的影响。MTT法检测17-EE对细胞增殖的影响,RT-PCR法观察成纤维细胞ATF3和CTGF表达情况。结果:尿道下裂患者包皮中ATF3和CTGF的表达显著高于正常人包皮组织(P<0.05);高浓度的17-EE干预对包皮成纤维细胞有抑制作用;在17-EE干预早期(1～2h)ATF3的表达呈现一过性增加;CTGF的表达在24h内17-EE干预未见明显变化。结论:ATF3和CTGF是与尿道下裂密切相关基因,雌激素可能通过上调ATF3和CTGF的表达参与调节生殖结节的异常发育,导致尿道下裂。

关键词： 尿道下裂   转录因子   免疫组织化学  

摘要： 目的探讨转录激活因子3(ATF3)在尿道下裂组织中的表达及其与尿道下裂程度的关系。方法收集28例尿道下裂组织,其中轻中度22例,重度6例,相应的正常环切包皮15例,采用免疫组化法检测ATF3的表达,分析蛋白阳性表达率。收集24例尿道下裂组织,其中轻中度8例,重度16例,对照为相应的正常环切包皮19例,采用RT-PCR法检测ATF3 mRNA的表达。结果ATF3蛋白在尿道下裂组织中表达阳性率为85.7%(24/28),在正常包皮组织中的表达阳性率为13.3%(2/15),ATF3蛋白在尿道下裂组织中的表达阳性率明显高于在正常包皮组织中的表达。重度尿道下裂ATF3蛋白阳性率100%(6/6),高于轻中度尿道下裂中的表达,在轻中度尿道下列中的表达为81.8%(18/22)。RT-PCR显示ATF3 mRNA表达在正常包皮组织、轻中度、重度尿道下裂组织中的相对累计光密度值比分别为(0.58±0.21)、(1.81±0.22)和(3.55±0.27),3组中的两两比较差异均有统计学意义。结论ATF3在尿道下裂组织中的表达明显上调,且与尿道下裂的程度显著相关,提示ATF3可能是尿道下裂发生中的一个候选基因。

关键词： experimental glaucoma   IOP elevation   neurotrophin   Trk receptor   p75(NTR)   Atf3   NEUROTROPHIC FACTOR BDNF   NERVE GROWTH-FACTOR   GANGLION-CELL SURVIVAL   NF-KAPPA-B   ACTIVATING TRANSCRIPTION FACTOR-3   MESSENGER-RNA LEVELS   OPTIC-NERVE   C-JUN   RAT RETINA   GENE-EXPRESSION  

摘要： Reduced retrograde transport of neurotrophins (NT) and their receptors has been hypothesized to contribute directly to retinal ganglion cell (RGC) loss in glaucoma. However, strategies of supplementing NT and NT receptors have failed to avert ultimate RGC death in experimental glaucoma. This study examines the response of major components of the NT system and their interacting proteins in a rat glaucoma model. Unilateral chronic intraocular pressure (IOP) elevation was produced by episcleral vein injection of hypertonic saline (N = 99). Retinas were collected and grouped by extent of optic nerve injury. Quantitative reverse transcription PCR, western blot analysis and immunohistochemistry were used to determine mRNA and protein levels and protein localization. Out of three RGC-specific Brn3 proteins (Brn3a, b, and c), only Brn3a was significantly downregulated at the message level to 35 +/- 4% of fellow values with the severest nerve injury. With IOP elevation, no significant alterations were found in retinal mRNA levels for BDNF, NGF, NT-4/5 or NT-3. The abundance of mature retinal BDNF protein was not significantly affected by elevated IOP, while proBDNF protein decreased linearly with increasing injury grade (r(2) = 0.50). In retinas with the severest nerve injury, TrkB and TrkC receptor mRNA levels significantly declined to 67 +/- 9% and 44 +/- 5% of fellow values, respectively. However, the levels of TRKB protein and its phosphorylated form were unchanged. Message level for p75(NTR) was linearly upregulated up to 219 +/- 26% with increasing injury (r(2) = 0.46), but no alteration was detected at protein level. The mRNA expression of p75(NTR) apoptosis adaptor proteins NADE, NRIF, and Lingo1 were significantly downregulated in retinas with the greatest nerve injury. A positive correlation was found between injury extent and message levels for Jun (r(2) = 0.23) as well as Junb (r(2) = 0.27), and RGC labeling of activated JUN protein increased. Atf3 mRNA levels de

关键词： Diabetic liver injury   ATF3   STAT1   Streptozotocin (STZ)   Apoptosis   INSULIN-RESISTANCE   NONALCOHOLIC STEATOHEPATITIS   HEPATOCELLULAR-CARCINOMA   IFN-GAMMA   T-CELLS   APOPTOSIS   EXPRESSION   DISEASE   RISK   GENE  

摘要： It is well-established that the administration of streptozotocin accelerates diabetic liver injury as well as type-1 diabetes, however the underlying mechanisms are poorly understood. Here we investigated the molecular mechanisms of diabetic liver injury in a model of streptozotocin (STZ)-induced type-1 diabetes. STZ administration induced type-1 diabetes and chronic liver injury was associated with increased STAT1, which is implicated in diabetic liver injury by virtue of its ability to promote hepatocyte apoptosis, in the liver and pancreas, which were all strongly inhibited in STAT1(-/-) mice. Similarly, STZ-induced ATF3, a stress-inducible gene, was completely abolished in the liver of IFN-gamma(-/-) mice, but not in STAT1(-/-) mice. Inhibition of STAT1 by siRNA or dominant-negative DNA did not affect ATF3 protein expression but blocked IFN-gamma-induced ATF3 translocation from the cytosol into the nucleus. In contrast, inhibition of ATF3 by using siRNA diminished STAT1 protein expression and IFN-gamma/STZ-induced hepatocyte apoptosis. Furthermore, GST pull-down and co-IP assay showed that STAT1 bound to C-terminal domain of ATF3. Such direct interaction increased the stability of STAT1 by inhibiting its ubiquitination as well as proteasome activity. Our results suggest that STAT1 is a common signaling pathway contributing to STZ-induced diabetes and diabetic liver injury. ATF3 functions as a potent regulator of STAT1 stability, accelerating STZ-induced diabetes and diabetic liver injury. (C) 2009 Elsevier Inc. All rights reserved.

关键词： ATF3   Transcriptional regulation   Immunity   TLRs   Oncogenesis   Gene expression   STRESS-INDUCIBLE GENE   BETA-CELL APOPTOSIS   PROSTATE-CANCER   NEGATIVE REGULATOR   EPITHELIAL-CELLS   UP-REGULATION   GADD153 GENE   EXPRESSION   BINDING   TUMORIGENESIS  

摘要： Activating transcription factor 3 (ATF3) is a member of the ATF/cyclic AMP response element-binding (ATF/CREB) family of transcription factors. It is an adaptive-response gene that participates in cellular processes to adapt to extra- and/or intracellular changes, where it transduces signals from various receptors to activate or repress gene expression. Advances made in understanding the immunobiology of Toll-like receptors have recently generated new momentum for the study of ATF3 in immunity. Moreover, the role of ATF3 in the regulation of the cell cycle and apoptosis has important implications for understanding susceptibility to and progression of several cancers.

关键词： penis   urethra   embryology   androgens   estrogens   ACTIVATING TRANSCRIPTION FACTOR-3   ANTI-ANDROGENS   HYPOSPADIAS   GENES   INDUCTION   ETIOLOGY   EXPOSURE   CELLS   ATF3  

摘要： Purpose: We developed an organotypic genital tubercle culture system in vitro and used it to investigate the direct effects of the hyperestrogenic state on fetal mouse penile and urethral development. Materials and Methods: Genital tubercles were dissected from embryonic day 14.5 C57B/L6 male mouse fetuses and cultured using an air-liquid interface on a microporous membrane support soaked in synthetic medium. Cultures were separated into 4 groups. Groups 1 to 3 were supplied with 10 nM dihydrotestosterone, estradiol and 10 nM dihydrotestosterone plus estradiol, respectively. Group 4 was cultured in hormone-free medium. After 36 to 72-hour culture morphological, histological, proliferation, apoptosis, androgen signaling and activating transcription factor 3 analyses were done. Results: The physiological concentration of 10 nM dihydrotestosterone was essential for genital tubercle growth in vitro. Androgen induced growth and urethral development were significantly suppressed by high dose estrogen. Concurrently we observed increased apoptosis and decreased proliferation in the mesenchyma. Androgen signaling was disrupted and activating transcription factor 3, a factor related to hypospadias genesis, was up-regulated. Conclusions: High dose estrogen suppressed male genital tubercle development in vitro. The organotypic genital tubercle culture system in vitro consisting of urethral epithelial and mesenchymal cells can recapitulate the hormonal sensitivity of fetal penile and urethral development. This method is potentially useful for studying the effects of various factors, particularly endocrine disruptors.

关键词： PBO   ROS   ATF3   liver   oxidative stress   ACTIVATING TRANSCRIPTION FACTOR-3   DNA-DAMAGE   C-MYC   FACTOR ATF3   OXIDATIVE STRESS   OVER-EXPRESSION   GENE-EXPRESSION   CYTOCHROME-P450   INDUCTION   RATS  

摘要： To clarify the mechanism of piperonyl butoxide (PBO)-induced hepatocarcinogenesis in mice, male mice were subjected to a two-thirds partial hepatectomy, N-diethylnitrosamine (DEN) initiation, and a diet containing 0.6% PBO for eight weeks. The incidence of gamma-glutamyl transpeptidase (GGT)-positive foci and PCNA-positive cells was significantly increased in the DEN + PBO group compared with the DEN-alone group. Real-time reverse transcription-polymerase chain reaction (RT-PCR) analysis showed up-regulation of genes related to metabolism, such as cytochrome P450 1A1 and 2B10, and metabolic stress, such as Por, Nqo1, Nrf2, abcc3, and abcc4. Early responsive genes downstream of mitogen-activated protein kinase (MAPK), such as c-fos, c-jun, c-myc, and activating transcription factor 3 (ATF3), were also up-regulated in this group. Positive immunohistochemical staining for ATF3 was diffusely observed in nonproliferating hepatocytes of the DEN + PBO group, but altered foci were negative or weakly positive for ATF3. The nuclei of hepatocytes within ATF3-negative foci were positive for cyclin D. Thus PBO can induce oxidative stress, activate the MAPK pathway, and increase ATF3 transcript levels in hepatocytes outside the altered foci during the early stage of PBO-induced hepatocarcinogenesis in mice.

关键词： Activating transcription factor 3   Mutant huntingtin   Polyglutamine   Huntington's disease   Cell death   GENE-EXPRESSION CHANGES   CREB-BINDING PROTEIN   MEDIATED TRANSCRIPTION   RESPONSE GENE   DISEASE   DYSFUNCTION   APOPTOSIS   DEATH   POLYGLUTAMINE   ACTIVATION  

摘要： Huntington's disease is a progressive neurodegenerative disorder caused by a polyglutamine expansion near the N-terminus of huntingtin. The mechanisms of polyglutamine neurotoxicity, and cellular responses are not fully understood. We have studied gene expression profiles by short oligo array using an inducible PC12 cell model expressing an N-terminal huntingtin fragment with expanded polyglutamine (Htt-N63-148Q) Mutant huntingtin Htt-N63 induced cell death and increased the mRNA and protein levels of activating transcription factor 3 (ATF3). Mutant Htt-N63 also significantly enhanced ATF3 transcriptional activity by a promoter-based reporter assay. Overexpression of ATF3 protects against mutant Htt-N63 toxicity and knocking down ATF3 expression reduced Htt-N63 toxicity in a stable PC12 cell line. These results indicated that ATF3 plays a critical role in toxicity induced by mutant Htt-N63 and may lead to a useful therapeutic target. (C) 2009 Elsevier B.V. All rights reserved.