Clinicopathologic significance of expression of nuclear factor-kB RelA and its target gene products in gastric cancer patients

AIM:To assess the prognostic significance of nuclear factor-kB (NF-kB) and its target genes in gastric cancer. METHODS:The tumor tissues of 115 patients with gastric cancer were immunohistochemically evaluated using monoclonal antibodies against NF-kB RelA. Preoperative serum levels of vascular endothelial growth factor (VEGF), interleukin-6 (IL-6) were assessed via enzyme-linked immuno-sorbent assay. C-reactive protein (CRP) and serum amyloid A (SAA) were measured via immunotrubidimetry. RESULTS:Positive rate of NF-kB RelA was 42.6%. NF-kB RelA expression in tumor tissues was also related to serum levels of IL-6 (P = 0.044) and CRP (P = 0.010). IL-6, SAA, CRP were related to depth of invasion, VEGF and SAA were correlated with lymph node metastasis. IL-6, VEGF, SAA and CRP were related to the stage. Univariate analysis demonstrated that immunostaining of NF-kB RelA, levels of IL-6, VEGF, SAA were significantly related with both disease free survival and over-all survival (OS). Multivariate analysis verified that NF-kB RelA [hazard ratio (HR): 3.40, P = 0.024] and SAA (HR: 3.39, P = 0.045) were independently associated with OS. CONCLUSION: Increased expression of NF-kB RelA and high levels of serum SAA were associated with poor OS in gastric cancer patients.

Evaluation of combined detection of nuclear factor erythroid 2-related factor 2 and glutathione peroxidase 4 in primary hepatic carcinoma and preliminary exploration of pathogenesis

This study aims to analyze the clinical significance and mechanism of nuclear factor erythroid 2-related factor 2(NRF2)and glutathione peroxidase 4(GPX4)in primary hepatic carcinoma(PHC).Methods:The expression of NRF2 and GPX4 in peripheral blood of patients with PHC was determined to analyze the diagnostic value of the two combined for PHC.The prognostic significance of NRF2 and GPX4 was evaluated by 3-year followup.Human liver epithelial cells THLE-2 and human hepatocellular carcinoma cells HepG2 were purchased,and the expression of NRF2 and GPX4 in the cells was determined.NRF2 and GPX4 aberrant expression vectors were constructed and transfected into HepG2,and changes in cell proliferation and invasion capabilities were observed.Results:The expression of NRF2 and GPX4 in patients with PHC was higher than that in patients with LC or VH(p<0.05),and the two indicators combined was excellent in diagnosing PHC.Moreover,patients with high expression of NRF2 and GPX4 had a higher risk of death(p<0.05).In in vitro experiments,both NRF2 and GPX4 expression was elevated in HepG2(p<0.05).HepG2 activity was enhanced by increasing the expression of the two,vice versa(p<0.05).Conclusion:NRF2 and GPX4 combined is excellent in diagnosing PHC,and promotes the malignant development of PHC.

Emerging trends and hotspots of Nuclear factor erythroid 2-related factor 2 in nervous system diseases

BACKGROUND The Nuclear factor erythroid 2-related factor 2(NRF2)transcription factor has attracted much attention in the context of neurological diseases.However,none of the studies have systematically clarified this field's research hotspots and evolution rules.AIM To investigate the research hotspots,evolution patterns,and future research trends in this field in recent years.METHODS We conducted a comprehensive literature search in the Web of Science Core Collection database using the following methods:(((((TS=(NFE2 L2))OR TS=(Nfe2 L2 protein,mouse))OR TS=(NF-E2-Related Factor 2))OR TS=(NRF2))OR TS=(NFE2L2))OR TS=(Nuclear factor erythroid2-related factor 2)AND(((((((TS=(neurological diseases))OR TS=(neurological disorder))OR TS=(brain disorder))OR TS=(brain injury))OR TS=(central nervous system disease))OR TS=(CNS disease))OR TS=(central nervous system disorder))OR TS=(CNS disorder)AND Language=English from 2010 to 2022.There are just two forms of literature available:Articles and reviews.Data were processed with the software Cite-Space(version 6.1.R6).RESULTS We analyzed 1884 articles from 200 schools in 72 countries/regions.Since 2015,the number of publications in this field has increased rapidly.China has the largest number of publications,but the articles published in the United States have better centrality and H-index.Among the top ten authors with the most published papers,five of them are from China,and the author with the most published papers is Wang Handong.The institution with the most articles was Nanjing University.To their credit,three of the top 10 most cited articles were written by Chinese scholars.The keyword co-occurrence map showed that"oxidative stress","NRF2","activation","expression"and"brain"were the five most frequently used keywords.CONCLUSION Research on the role of NRF2 in neurological diseases continues unabated.Researchers in developed countries published more influential papers,while Chinese scholars provided the largest number of articles.There have been numerous studies on the mechanism of NRF2 transcription factor in neurological diseases.NRF2 is also emerging as a potentially effective target for the treatment of neurological diseases.However,despite decades of research,our knowledge of NRF2 transcription factor in nervous system diseases is still limited.Further studies are needed in the future.

Single-nuclei RNA sequencing uncovers heterogenous transcriptional signatures in Parkinson's disease associated with nuclear receptor-related factor 1 defect

Previous studies have found that deficiency in nuclear receptor-related factor 1(Nurr1),which participates in the development,differentiation,survival,and degeneration of dopaminergic neurons,is associated with Parkinson s disease,but the mechanism of action is perplexing.Here,we first asce rtained the repercussion of knocking down Nurr1 by pe rforming liquid chromatography coupled with tandem mass spectrometry.We found that 231 genes were highly expressed in dopaminergic neurons with Nurr1 deficiency,14 of which were linked to the Parkinson’s disease pathway based on Kyoto Encyclopedia of Genes and Genomes analysis.To better understand how Nurr1 deficiency autonomously invokes the decline of dopaminergic neurons and elicits Parkinson’s disease symptoms,we performed single-nuclei RNA sequencing in a Nurr1 LV-shRNA mouse model.The results revealed cellular heterogeneity in the substantia nigra and a number of activated genes,the preponderance of which encode components of the major histocompatibility Ⅱ complex.Cd74,H2-Ab1,H2-Aα,H2-Eb1,Lyz2,Mrc1,Slc6α3,Slc47α1,Ms4α4b,and Ptprc2 were the top 10 diffe rentially expressed genes.Immunofluorescence staining showed that,after Nurr1knockdown,the number of CD74-immunoreactive cells in mouse brain tissue was markedly increased.In addition,Cd74 expression was increased in a mouse model of Parkinson’s disease induced by treatment with 6-hydroxydopamine.Ta ken togethe r,our res ults suggest that Nurr1 deficiency results in an increase in Cd74 expression,thereby leading to the destruction of dopaminergic neuro ns.These findings provide a potential therapeutic target for the treatment of Parkinson’s disease.

舒芬太尼调节TLR4/MyD88/NF-kB通路对重症肺炎大鼠肺损伤的影响

目的:探讨舒芬太尼(Sufentanil,Sufen)对重症肺炎(Severe pneumonia,SP)大鼠肺损伤及Toll样受体4/髓样分化因子88/核因子-κB(Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB,TLR4/MyD88/NF-κB)通路的影响。方法:构建SP大鼠模型;将造模成功大鼠分为重症肺炎组(SP组)、舒芬太尼低、高剂量组(Sufen-L、Sufen-H组)、舒芬太尼高剂量+TLR4激活剂LPS组(Sufen-H+LPS组),每组24只,另取24只正常大鼠作为对照组(Control组);检测肺泡灌洗液中炎症因子水平及肺泡灌洗液沉淀物中炎症细胞数目;检测肺组织湿干重比(Wet/Dry,W/D);HE染色观察各组大鼠肺组织病理变化;Western blot检测肺组织中TLR4、MyD88、p-NF-κB p65/NF-κB p65表达水平。结果:SP组较Control组肺组织遭到破坏损伤严重,其中肺间质增厚,肺泡水肿并伴有大量炎性细胞浸润,TNF-α、IL-1β、IL-6水平和EOS、NEU炎症细胞数目及W/D比、TLR4、MyD88、p-NF-κB p65/NF-κB p65蛋白表达显著升高(P<0.05);Sufen-L、Sufen-H组较SP组大鼠肺组织损伤减轻,肺泡结构逐渐完整,水肿减轻,炎症细胞浸润逐渐减少,TNF-α、IL-1β、IL-6水平和EOS、NEU炎症细胞数目及W/D比、TLR4、MyD88、p-NF-κB p65/NF-κB p65蛋白表达显著降低,其中Sufen-H组优于Sufen-L组(P<0.05);Sufen-H+LPS组较Sufen-H组大鼠肺组织损伤加剧,肺泡结构破坏严重,肺泡水肿明显,炎性细胞浸润增加,TNF-α、IL-1β、IL-6水平和EOS、NEU炎症细胞数目及W/D比、TLR4、MyD88、p-NF-κB p65/NF-κB p65蛋白表达显著升高(P<0.05)。结论:Sufen改善SP大鼠的肺损伤,与抑制TLR4/MyD88/NF-κB信号通路有关。

Assessment of Axial Power Peaking Factors in GHARR-1 LEU Core: A Decadal Simulation Analysis

This study aims to thoroughly investigate the axial power peaking factors (PPF) within the low-enriched uranium (LEU) core of the Ghana Research Reactor-1 (GHARR-1). This study uses advanced simulation tools, like the MCNPX code for analysing neutron behavior and the PARET/ANL code for understanding power variations, to get a clearer picture of the reactor’s performance. The analysis covers the initial six years of GHARR-1’s operation and includes projections for its whole 60-year lifespan. We closely observed the patterns of both the highest and average PPFs at 21 axial nodes, with measurements taken every ten years. The findings of this study reveal important patterns in power distribution within the core, which are essential for improving the safety regulations and fuel management techniques of the reactor. We provide a meticulous approach, extensive data, and an analysis of the findings, highlighting the significance of continuous monitoring and analysis for proactive management of nuclear reactors. The findings of this study not only enhance our comprehension of nuclear reactor safety but also carry significant ramifications for sustainable energy progress in Ghana and the wider global context. Nuclear engineering is essential in tackling global concerns, such as the demand for clean and dependable energy sources. Research on optimising nuclear reactors, particularly in terms of safety and efficiency, is crucial for the ongoing advancement and acceptance of nuclear energy.

基于TLR4/MyD88/NF-kB信号通路探讨追风透骨胶囊减缓兔膝骨关节炎模型软骨退变的作用机制

目的 观察追风透骨胶囊对兔膝骨关节炎(knee osteoarthritis, KOA)模型关节软骨退变的干预作用,并基于Toll样受体4(Toll like receptor 4, TLR4)/髓细胞分化初级反应蛋白88(myeloid differentiation primary response protein 88, MyD88)/核因子kappa-B(nuclear factor kappa-B, NF-κB)信号通路探讨追风透骨胶囊的可能作用机制。方法 从50只6月龄雄性新西兰兔中随机选取10只作为正常组,其余40只为KOA造模组,用改良Videman造模法制备兔KOA模型。模型验证后,从正常组中随机选取6只作为空白组(A组),KOA造模组抽取30只随机分为模型组(B组)、硫酸氨基葡萄糖组(C组)、追风透骨胶囊低剂量组(D组)、追风透骨胶囊中剂量组(E组)、追风透骨胶囊高剂量组(F组),每组6只。A、B组予蒸馏水灌胃,C、D、E、F组予相应药物灌胃,疗程均为6周。给药结束后,取造模侧膝关节软骨,予大体及HE染色观察,并用Pelletier评分及Mankin评分评估;以Western blot、RT-PCR法检测软骨中TLR4、My D88、NF-κB蛋白及其mRNA的表达;免疫组化法检测白细胞介素-1β(interleukin-1β, IL-1β)、白细胞介素-6(interleukin-6, IL-6)、肿瘤坏死因子-α(tumor necrosis factor-α, TNF-α)的含量。结果 与A组比较,B组膝关节软骨破坏明显,Pelletier评分及Mankin评分均升高(P<0.01),软骨中TLR4、MyD88、NF-κB蛋白及其mRNA表达水平均上调(P<0.01),IL-1β、IL-6、TNF-α含量均升高(P<0.01)。与B组比较,C、D、E、F组的软骨损伤程度轻,软骨Mankin评分均降低(P<0.01),软骨中TLR4、MyD88、NF-κB蛋白及m RNA表达水平均下调(P<0.01),IL-1β、IL-6、TNF-α含量均降低(P<0.01),此外,F组软骨Pelletier评分较B组降低明显(P<0.05)。结论 追风透骨胶囊能延缓改良Videman造模法诱导的兔KOA模型关节软骨退变,其作用机制可能与下调软骨中TLR4、MyD88、NF-κB蛋白及m RNA的表达,抑制TLR4/MyD88/NF-κB信号通路的活化,降低IL-1β、IL-6、TNF-α在软骨中的含量,从而减轻炎症反应相关。

Effects of β-Aescin on the expression of nuclear factor-κB and tumor necrosis factor-α after traumatic brain injury in rats

To investigate the inhibiting effect of β-Aescin on nuclear factor-κB (NF-κB) activation and the expression of tumor necrosis factor-α (TNF-α) protein after traumatic brain injury (TBI) in the rat brain, 62 SD rats were subjected to lateral cortical impact injury caused by a free-falling object and divided randomly into four groups: (1) sham operated (Group A); (2) injured (Group B); (3) β-Aescin treatment (Group C); (4) pyrrolidine dithocarbamate (PDTC) treatment (Group D). β-Aescin was administered in Group C and PDTC treated in Group D immediately after injury. A series of brain samples were obtained directly 6h, 24 h and 3 d respectively after trauma in four groups. NF-κB activation was examined by Electrophoretic Mobility Shift Assay (EMSA); the levels of TNF-α protein were measured by radio-immunoassay (RIA); the water content of rat brain was measured and pathomorphological observation was carried out. NF-κB activation, the levels of TNF-α protein and the water content of rat brain were significantly increased (P＜0.01) following TBI in rats. Compared with Group B, NF-κB activation (P＜0.01), the levels of TNF-α protein (P＜0.01) and the water content of brain (P＜0.05) began to decrease obviously after injury in Groups C and D.β-Aescin could dramatically inhibit NF-κB activation and the expression of TNF-α protein in the rat brain, alleviate rat brain edema, and that could partially be the molecular mechanism by which β-Aescin attenuates traumatic brain edema.

粉防己碱调节Toll样受体4/核因子-kB通路在子痫前期大鼠模型中的影响

目的探究粉防己碱(Tet)调节Toll样受体4(TLR4)/核因子(NF)-κB通路对子痫前期(PE)大鼠模型的影响。方法20只SPF级Wistar雄性大鼠,40只雌性大鼠,进行PE大鼠建模,将20只妊娠大鼠随机分为两组,即A组与B组,每组10只;A组分为PE-1组与PE+Tet-1组,每组5只;B组分为PE-2组与PE+Tet-2组,每组5只。比较PE+Tet-1组与PE-1组、PE+Tet-2组与PE-2组妊娠各时间点血压、尿蛋白及胎盘重量、胎鼠重量、炎症因子、TLR4和NF-κB蛋白表达。结果妊娠第10天,PE+Tet-1组与PE-1组血压比较差异无统计学意义;妊娠第15、20天,PE+Tet-1组血压均低于PE-1组,差异有统计学意义(P<0.05)。妊娠第10、15天,PE+Tet-2组与PE-2组血压比较差异无统计学意义;妊娠第20天,PE+Tet-2组血压低于PE-2组,差异有统计学意义(P<0.05)。妊娠第10天,PE+Tet-1组与PE-1组24 h尿蛋白水平比较差异无统计学意义;妊娠第15、20天,PE+Tet-1组24 h尿蛋白水平均低于PE-1组,差异有统计学意义(P<0.05)。妊娠第10、15、20天,PE+Tet-2组与PE-2组24 h尿蛋白水平比较差异无统计学意义。PE+Tet-1组胎盘和胎鼠重量均大于PE-1组,差异有统计学意义(P<0.05);PE+Tet-2组胎盘和胎鼠重量均大于PE-2组,差异有统计学意义(P<0.05)。PE+Tet-1组IL-6、TNF-α水平均低于PE-1组,差异有统计学意义(P<0.05);PE+Tet-2组IL-6和TNF-α水平均低于PE-2组,差异有统计学意义(P<0.05)。PE+Tet-1组TLR4和NF-κB蛋白水平均明显低于PE-1组,差异有统计学意义(P<0.05);PE+Tet-2组TLR4和NF-κB蛋白水平均明显低于PE-2组,差异有统计学意义(P<0.05)。结论Tet调节TLR4/NF-κB通路对PE大鼠模型,可降低PE模型大鼠的血压,减少24 h尿蛋白,增加胎盘和胎鼠质量,促进胎鼠发育,抑制炎症因子的表达。

Delayed hepatocarcinogenesis through antiangiogenic intervention in the nuclear factor-kappa B activation pathway in rats

BACKGROUND: The active form of nuclear factor-kappa B (NF-kappa B) is involved in the initiation, generation, and development of hepatocellular carcinoma (HCC), and is up-regulated in inflammation-associated malignancies. We investigated the dynamic expression of NF-kappa B and its influences on the occurrence of HCC through antiangiogenic (thalidomide) intervention in NF-kappa B activation. METHODS : Hepatoma models were induced with 2-fluorenylacetamide (2-FAA, 0.05%) in male Sprague-Dawley rats, and thalidomide (100 mg/kg body weight) was administered intragastrically to intervene in NF-kappa B activation. The pathological changes in the liver of sacrificed rats were assessed after hematoxylin and eosin staining. NF-kappa B mRNA was amplified by RT-nested PCR. The alterations of NF-kappa B and vascular endothelial growth factor (VEGF) expression were analyzed by enzyme-linked immunosorbent assay, immunohistochemistry, and Western blotting. RESULTS: Rat hepatocytes showed denatured, precancerous, and cancerous stages in hepatocarcinogenesis, with an increasing tendency of hepatic NF-kappa B, NF-kappa B mRNA, and VEGF expression, and their values in the HCC group were higher than those in controls (P<0.001). In the thalidomide-treated group, the morphologic changes generated only punctiform denaturation and necrosis at the early or middle stages, and nodular hyperplasia or a little atypical hyperplasia at the final stages, with the expression of NF-kappa B (chi(2)=9.93, P<0.001) and VEGF (chi(2)=8.024, P<0.001) lower than that in the 2-FAA group. CONCLUSION: NF-kappa B is overexpressed in hepatocarcinogenesis and antiangiogenic treatment down-regulates the expression of NF-kappa B and VEGF, and delays the occurrence of HCC. (Hepatobiliary Pancreat Dis Int 2010; 9: 169-174)

Role of osteoprotegerin/receptor activator of nuclear factor kappa B/receptor activator of nuclear factor kappa B ligand axis in nonalcoholic fatty liver disease

Concomitantly with the increase in the prevalences of overweight/obesity, nonalcoholic fatty liver disease(NAFLD) has worldwide become the main cause of chronic liver disease in both adults and children. Patients with fatty liver display features of metabolic syndrome(Met S), like insulin resistance(IR), glucose intolerance, hypertension and dyslipidemia. Recently, epidemiological studies have linked obesity, Met S, and NAFLD to decreased bone mineral density and osteoporosis, highlighting an intricate interplay among bone, adipose tissue, and liver. Osteoprotegerin(OPG), an important symbol of the receptor activator of nuclear factor-B ligand/receptor activator of nuclear factor kappa B/OPG system activation, typically considered for its role in bone metabolism, may also play critical roles in the initiation and perpetuation of obesityrelated comorbidities. Clinical data have indicated that OPG concentrations are associated with hypertension, left ventricular hypertrophy, vascular calcification, endothelial dysfunction, and severity of liver damage in chronic hepatitis C. Nonetheless, the relationship between circulating OPG and IR as a key feature of Met S as well as between OPG and NAFLD remains uncertain. Thus, the aims of the present review are to provide the existent knowledge on these associations and to discuss briefly the underlying mechanisms linking OPG and NAFLD.

Hepatocyte nuclear factor 4-alpha involvement in liver and intestinal inflammatory networks

Hepatocyte nuclear factor 4-alpha(HNF4-α)is a nuclear receptor regulating metabolism,cell junctions,differentiation and proliferation in liver and intestinal epithelial cells.Mutations within the HNF4A gene are associated with human diseases such as maturityonset diabetes of the young.Recently,HNF4A has also been described as a susceptibility gene for ulcerative colitis in genome-wide association studies.In addition,specific HNF4A genetic variants have been identified in pediatric cohorts of Crohn’s disease.Results obtained from knockout mice supported that HNF4-αcan protect the intestinal mucosae against inflammation.However,the exact molecular links behind HNF4-αand inflammatory bowel diseases remains elusive.In this review,we will summarize the current knowledge about the role of HNF4-αand its isoforms in inflammation.Specific nature of HNF4-αP1 and P2 classes of isoforms will be summarized.HNF4-αrole as a hepatocyte mediator for cytokines relays during liver inflammation will be integrated based on documented examples of the literature.Conclusions that can be made from these earlier liver studies will serve as a basis to extrapolate correlations and divergences applicable to intestinal inflammation.Finally,potential functional roles for HNF4-αisoforms in protecting the intestinal mucosae from chronic and pathological inflammation will be presented.

Neuroprotective effects of salidroside on focal cerebral ischemia/reperfusion injury involve the nuclear erythroid 2-related factor 2 pathway

Salidroside,the main active ingredient extracted from Rhodiola crenulata,has been shown to be neuroprotective in ischemic cerebral injury,but the underlying mechanism for this neuroprotection is poorly understood.In the current study,the neuroprotective effect of salidroside on cerebral ischemia-induced oxidative stress and the role of the nuclear factor erythroid 2-related factor 2（Nrf2）pathway was investigated in a rat model of middle cerebral artery occlusion.Salidroside（30 mg/kg）reduced infarct size,improved neurological function and histological changes,increased activity of superoxide dismutase and glutathione-S-transferase,and reduced malon-dialdehyde levels after cerebral ischemia and reperfusion.Furthermore,salidroside apparently increased Nrf2 and heme oxygenase-1 expression.These results suggest that salidroside exerts its neuroprotective effect against cerebral ischemia through anti-oxidant mechanisms and that activation of the Nrf2 pathway is involved.The Nrf2/antioxidant response element pathway may become a new therapeutic target for the treatment of ischemic stroke.

Expression of germ cell nuclear factor in mouse germ cells and sperm during postnatal period

Aim: To assess the spatial and temporal expression of germ cell nuclear factor (GCNF) in male mouse germ cells during postnatal development and in sperm before and after capacitation. Methods: The indirect immun-ofluorescence method with anti-GCNF antiserum was used to investigate the GCNF expression in mice at day 8, 10, 14, 17, 20, 28, 35, 70, and 420 after birth and in sperm before and after capacitation. Results: With the proceeding of spermatogenesis, GCNF was first detected in the nuclei of spermatogonia and a few early stage primary sperma-tocytes at day 8, which was increased gradually at day 10 to 14 inclusive. From day 17 to day 20, the GCNF was concentrated in round spermatids, while both spermatogonia and early stage primary spermatocytes became GCNF negative. From day 28 until day 420, strong GCNF expression was shown in round spermatids and pachytene spermatocytes, while spermatogonia, early primary spermatocytes and elongating spermatids were all GCNF negative. In addition, it was also found that GCNF was localized on the acrosomal cap region of spermatozoa and there was a big change in GCNF expression during capacitation, from 98 % GCNF positive before capacitation to about 20 % positive following capacitation. The localization of GCNF in caput and cauda spermatozoa was similar. Conclusion: GCNF may play important roles in spermatogenesis, capacitation and fertilization.

Roles of hepatocyte nuclear factors in hepatitis B virus infection

Approximately 350 million people are estimated to be persistently infected with hepatitis B virus(HBV) worldwide. HBV maintains persistent infection by employing covalently closed circular DNA(ccc DNA), a template for all HBV RNAs. Chronic hepatitis B(CHB) patients are currently treated with nucleos(t)ide analogs such as lamivudine, adefovir, entecavir, and tenofovir. However, these treatments rarely cure CHB because they are unable to inhibit ccc DNA transcription and inhibit only a late stage in the HBV life cycle(the reverse transcription step in the nucleocapsid). Therefore, an understanding of the factors regulating ccc DNA transcription is required to stop this process. Among numerous factors, hepatocyte nuclear factors(HNFs) play the most important roles in ccc DNA transcription, especially in the generation of viral genomic RNA, a template for HBV replication. Therefore, proper control of HNF function could lead to the inhibition of HBV replication. In this review, we summarize and discuss the current understanding of the roles of HNFs in the HBV life cycle and the upstream factors that regulate HNFs. This knowledge will enable the identification of new therapeutic targets to cure CHB.

Role of hepatocyte nuclear factor 4-alpha in gastrointestinal and liver diseases

Hepatocyte nuclear factor 4-alpha(HNF4α)is a highly conserved member of nuclear receptor superfamily of ligand-dependent transcription factors that is expressed in liver and gastrointestinal organs(pancreas,stomach,and intestine).In liver,HNF4αis best known for its role as a master regulator of liver-specific gene expression and essential for adult and fetal liver function.Dysregulation of HNF4αexpression has been associated with many human diseases such as ulcerative colitis,colon cancer,maturity-onset diabetes of the young,liver cirrhosis,and hepatocellular carcinoma.However,the precise role of HNF4αin the etiology of these human pathogenesis is not well understood.Limited information is known about the role of HNF4αisoforms in liver and gastrointestinal disease progression.There is,therefore,a critical need to know how disruption of the expression of these isoforms may impact on disease progression and phenotypes.In this review,we will update our current understanding on the role of HNF4αin human liver and gastrointestinal diseases.We further provide additional information on possible use of HNF4αas a target for potential therapeutic approaches.

Role of nuclear factor kappa B in central nervous system regeneration

Activation of nuclear factor kappa B （NF-κB） is a hallmark of various central nervous system （CNS） pathologies. Neuron-specific inhibition of its transcriptional activator subunit RelA, also referred to as p65, promotes neuronal survival under a range of conditions, i.e., for ischemic or excitotoxic insults. In macro- and microglial cells, post-lesional activation of NF-κB triggers a growth-permissive program which contributes to neural tissue inflammation, scar formation, and the expression of axonal growth inhibitors. Intriguingly, inhibition of such inducible NF-~B in the neuro-glial compartment, i.e., by genetic ablation of RelA or overexpression of a trans- dominant negative mutant of its upstream regulator IκBa, significantly enhances functional recovery and promotes axonal regeneration in the mature CNS. By contrast, depletion of the NF-κB subunit p50, which lacks transcriptional activator function and acts as a transcriptional repressor on its own, causes precocious neuronal loss and exacerbates axonal degeneration in the lesioned brain. Collectively, the data imply that NF-κB orchestrates a multicellular pro- gram in which κB-dependent gene expression establishes a growth-repulsive terrain within the post-lesioned brain that limits structural regeneration of neuronal circuits. Considering these subunit-specific functions, interference with the NF-κB pathway might hold clinical potentials to improve functional restoration following traumatic CNS injury.

Effects of nuclear factor κB expression on retinal neovascularization and apoptosis in a diabetic retinopathy rat model

AIM: To investigate the expression and role of nuclear factor κB(NF-κB) in diabetic retinopathy(DR) and its relationship with neovascularization and retinal cell apoptosis. METHODS: A total of 80 male Wistar rats were randomly assigned to control(4, 8, 12 and 16 wk, n =10 in each group) and diabetes mellitus(DM) groups(4, 8, 12 and 16wk, n =10 in each group). A diabetic rat model was established by intraperitoneal injection of streptozotocin(60 mg/kg). After 4, 8, 12 and 16 wk, rats were sacrificed.Retinal layers and retinal neovascularization growth were stained with hematoxylin-eosin and examined under light microscopy. Cell apoptosis in the retina was detected by Td T-mediated d UTP nick end labeling, and NF-κB distribution and expression in the retina was determined using immunohistochemistry. RESULTS: DM model success rate up to 100%.Diabetes model at each time point after the experimental groupcompared with the control group, the blood glucose was significantly increased, decreased body weight, each time point showed significant differences compared with the control group(P 【0.01). After 12 wk other pathological changes in the retina of diabetic rats were observed; after 16 wk, neovascularization were observed. After 1mo, retinal cell apoptosis was observed.Compared with the control group, NF-κB expression in the DM group significantly increased with disease duration.CONCLUSION: With the prolonging of DM progression,the expression NF-κB increases. NF-κB may be related to retinal cell apoptosis and neovascularization.

Spatial and temporal expression of germ cell nuclear factorin murine epididymis

Aim: To investigate the spatial and temporal expression of germ cell nuclear factor (GCNF) in mouse and rat epididymis during postnatal period. Methods: The epididymal sections from different postnatal days were stained for GCNF by the indirect immunofluorescence technique and digital photographs were taken by a Carl Zeiss confocal microscope. Results: GCNF was first detected on day 12 in mouse epididymis and day 14 in rat epididymis. The highest expression of GCNF was observed on day 35 in both mouse and rat epididymis. In adults, GCNF exhibited a region-specific expression pattern, i.e., it was expressed predominantly in the initial segment, caput and proximal corpus of rat epididymis and was abundant in the proximal corpus of mouse epididymis. GCNF could be found in the nuclei of the principal, apical, narrow, clear and halo cells. Conclusion: GCNF may play an important role in epididymal differentiation and development and in sperm maturation.

High levels of homocysteine downregulate apolipoprotein E expression via nuclear factor kappa B

AIM: To investigate the effect of high homocysteine(Hcy) levels on apolipoprotein E(apoE) expression and the signaling pathways involved in this gene regulation.METHODS: Reverse transcriptase polymerase chain reaction(RT-PCR) and Western blot were used to assess apo E expression in cells treated with various concentrations(50-500 μmol/L) of Hcy. Calcium phosphatetransient transfections were performed in HEK-293 and RAW 264.7 cells to evaluate the effect of Hcy on apoE regulatory elements [promoter and distal multienhancer 2(ME2)]. To this aim, plasmids containing the proximal apoE promoter [(-500/+73)apoE construct] alone or in the presence of ME2 [ME2/(-500/+73)apoE construct] to drive the expression of the reporter luciferase gene were used. Co-transfection experiments were carried out to investigate the downstream effectors of Hcymediated regulation of apoE promoter by using specific inhibitors or a dominant negative form of IKβ. In other co-transfections, the luciferase reporter was under the control of synthetic promoters containing multiple specific binding sites for nuclear factor kappa B(NF-κB), activator protein-1(AP-1) or nuclear factor of activated T cells(NFAT). Chromatin immunoprecipitation(ChI P)assay was accomplished to detect the binding of NF-κB p65 subunit to the apoE promoter in HEK-293 treated with 500 μmol/L Hcy. As control, cells were incubated with similar concentration of cysteine. NF-κB p65 proteins bound to DNA were immunoprecipitated with anti-p65 antibodies and DNA was identified by PCR using primers amplifying the region-100/+4 of the apoE gene. RESULTS: RT-PCR revealed that high levels of Hcy(250-750 μmol/L) induced a 2-3 fold decrease in apoE m RNA levels in HEK-293 cells, while apo E gene expression was not significantly affected by treatment with lower concentrations of Hcy(100 μmol/L). Immunoblotting data provided additional evidence for the negative role of Hcy in apoE expression. Hcy decreased apoE promoter activity, in the presence or absence of ME2, in a dose dependent manner, in both RAW 264.7 and HEK-293 cells, as revealed by transient transfection experiments. The downstream effectors of the signaling pathways of Hcy were also investigated. The inhibitory effect of Hcy on the apo E promoter activity was counteracted by MAPK/ERK kinase 1/2(MEK1/2) inhibitor U0126, suggesting that MEK1/2 is involved in the downregulation of apoE promoter activity by Hcy. Our data demonstrated that Hcy-induced inhibition of apoE took place through activation of NF-κB. Moreover, we demonstrated that Hcy activated a synthetic promoter containing three NF-κB binding sites, but did not affect promoters containing AP-1 or NFAT binding sites. ChI P experiments revealed that NF-κB p65 subunit is recruited to the apoE promoter following Hcy treatment of cells.CONCLUSION: Hcy-induced stress negatively modulates apoE expression via MEK1/2 and NF-κB activation. The decreased apo E expression in peripheral tissues may aggravate atherosclerosis, neurodegenerative diseases and renal dysfunctions.