Synergistic regulation of inducible nitric oxide synthase gene by CCAAT/enhancer‐binding protein β and nuclear factor‐κB in hepatocytes

Sakitani, Kazushige; Nishizawa, Mikio; Inoue, Katsumi; Masu, Yasuo; Okumura, Tadayoshi; Ito, Seiji

doi:10.1046/j.1365-2443.1998.00193.x

Cited by 62 publications

(44 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We reported that NF-B and CCAAT/enhancer-binding protein ␤ (C/EBP␤) synergistically activated the transcription of iNOS in hepatocytes. 45 It seems likely that hypoxia affects one of these pathways, which have a crucial role for NF-B-induced transcription in addition to its DNA binding. In the case of heat, heat inhibited the iNOS induction by preventing the degradation of I B and the NF-B DNA binding.…”

Section: Discussionmentioning

confidence: 99%

Hypoxia and Heat Inhibit Inducible Nitric Oxide Synthase Gene Expression by Different Mechanisms in Rat Hepatocytes

Inoue

2000

Hepatology

View full text Add to dashboard Cite

Ischemia/reperfusion contributes to the hepatic injury in resection and transplantation of the liver. However, the precise mechanisms involved in hypoxia stress remain to be clarified. Pro-inflammatory cytokines including interleukin 1␤ (IL-1␤) induce a gene expression of inducible nitric oxide synthase (iNOS) and produce nitric oxide, which exerts either a cytoprotective or toxic effect. In this report, we found that hypoxia and heat markedly inhibited the induction of nitric oxide production stimulated by IL-1␤ in rat cultured hepatocytes. Both treatments also abolished the induction of iNOS protein and mRNA. However, hypoxia could not prevent either degradation of an inhibitory protein (I B␣)

show abstract

Section: Discussionmentioning

confidence: 99%

Hypoxia and Heat Inhibit Inducible Nitric Oxide Synthase Gene Expression by Different Mechanisms in Rat Hepatocytes

Inoue

2000

Hepatology

View full text Add to dashboard Cite

show abstract

“…C/EBPb cooperates with the p50 subunit of NF-kB on the Nur77 promoter Because the Nur77 promoter was previously shown to contain a kB element at K427 bp known to bind the NF-kB transcription factor (Pei et al 2005) and because NF-kB and C/EBPb can cooperate in other systems (Sakitani et al 1998, Montaner et al 1999, we tested whether NF-kB could activate and/or cooperate with C/EBPb on the Nur77 promoter in Leydig cells. Expression vectors encoding C/EBPb and each of the NF-kB subunits (p50 and p65) were transiently transfected in MA-10 Leydig cells along with a K1013 bp rat Nur77 reporter.…”

Section: C/ebpb Binds To and Activates The Nur77 Promotermentioning

confidence: 99%

Transcriptional cooperation between NF-κB p50 and CCAAT/enhancer binding protein β regulates Nur77 transcription in Leydig cells

El-Asmar¹,

Giner²,

Tremblay

2008

Journal of Molecular Endocrinology

View full text Add to dashboard Cite

Expression of steroidogenic enzyme-encoding genes in testicular Leydig cells is complex and involves several transcription factors including the orphan nuclear receptor NUR77 (NR4A1) and the bZIP factor CCAAT/enhancer binding protein b (EBPb). How these transcription factors are integrated into a functional network, however, remains to be fully understood. Here, we report that the transcription factor C/EBPb can activate the Nur77 promoter as revealed by transient transfections in MA-10 Leydig cells. Through 5 0 progressive deletions and site-directed mutagenesis, the C/EBPb-mediated activation of the Nur77 promoter was found to be dependent on a novel species-conserved C/EBP element located at K110 bp. We also demonstrate using electromobility shift assay that C/EBPb specifically binds to this element. Furthermore, we report a functional cooperation between C/EBPb and the p50 subunit of NF-kB that involves a previously uncharacterized kB element located at K18 bp. Promoter analysis revealed that either the C/EBP or the kB element was sufficient to sustain the C/EBPb-p50 cooperation thus suggesting that both factors physically interact. Altogether, our results provide new data regarding Nur77 transcription in testicular Leydig cells in addition to providing new insights into the interplay between transcription factors involved in Leydig cell gene expression and function.

show abstract

“…Rat hepatocytes were isolated and maintained as previously described (Sakitani et al 1998). Porcine granulosa cells were prepared according to published methods (Fukuoka et al 1988).…”

Section: Cell Culturementioning

confidence: 99%

“…The transfection of hepatocytes was performed according to previously described methods (Sakitani et al 1998). Similarly, on Human 20a-HSD gene and three AKR genes q Blackwell Science Limited day 4 hCG-treated granulosa cells were transfected with 20 mg of LipofectAMINE (Life Technologies, USA), 2 mg of reporter plasmid DNA and 2 ng of pCMV-LacZ as an internal control.…”

Section: Transfection and ®Re¯y Luciferase Assaymentioning

confidence: 99%

Close kinship of human 20α‐hydroxysteroid dehydrogenase gene with three aldo‐keto reductase genes

Nishizawa¹,

et al. 2000

Self Cite

View full text Add to dashboard Cite

Background: 20a-Hydroxysteroid dehydrogenase (HSD) is a member of the aldo-keto reductase (AKR) superfamily and catalyses the reaction of progesterone to the inactive form 20a-hydroxyprogesterone. Progesterone plays an important role in the maintenance of pregnancy, and, in rodents, plasma progesterone levels decrease abruptly just before parturition. The induction of 20a-HSD is thought to be responsible for the decrease in plasma progesterone at term. High homology between human 20a-HSD [AKR 1C1] cDNA with other AKRs had caused dif®culty in gene isolation and expression analysis. Thus, the metabolism of progesterone in the human reproductive system remained unclear.

show abstract

Synergistic regulation of inducible nitric oxide synthase gene by CCAAT/enhancer‐binding protein β and nuclear factor‐κB in hepatocytes

Cited by 62 publications

References 46 publications

Hypoxia and Heat Inhibit Inducible Nitric Oxide Synthase Gene Expression by Different Mechanisms in Rat Hepatocytes

Hypoxia and Heat Inhibit Inducible Nitric Oxide Synthase Gene Expression by Different Mechanisms in Rat Hepatocytes

Transcriptional cooperation between NF-κB p50 and CCAAT/enhancer binding protein β regulates Nur77 transcription in Leydig cells

Close kinship of human 20α‐hydroxysteroid dehydrogenase gene with three aldo‐keto reductase genes

Contact Info

Product

Resources

About