The World Health Organization and Global Health Governance: post-1990.

This article takes a historical perspective on the changing position of WHO in the global health architecture over the past two decades. From the early 1990s a number of weaknesses within the structure and governance of the World Health Organization were becoming apparent, as a rapidly changing post Cold War world placed more complex demands on the international organizations generally, but significantly so in the field of global health. Towards the end of that decade and during the first half of the next, WHO revitalized and played a crucial role in setting global health priorities. However, over the past decade, the organization has to some extent been bypassed for funding, and it lost some of its authority and its ability to set a global health agenda. The reasons for this decline are complex and multifaceted. Some of the main factors include WHO's inability to reform its core structure, the growing influence of non-governmental actors, a lack of coherence in the positions, priorities and funding decisions between the health ministries and the ministries overseeing development assistance in several donor member states, and the lack of strong leadership of the organization.

Expression level-dependent contribution of glucocorticoid receptor domains for functional interaction with STAT5.

The action of the glucocorticoid receptor (GR) on beta-casein gene transcription serves as a well-studied example of a case where the action of the GR is dependent on the activity of another transcription factor, STAT5. We have investigated the domain-requirement of the GR for this synergistic response in transfection experiments employing GR mutants and CV-1 or COS-7 cells. The results were influenced by the expression levels of the GR constructs. At low expression, STAT5-dependent transactivation by mutants of the GR DNA binding domain or N-terminal transactivation domain was impaired and the antiglucocorticoid RU486 exhibited a weak agonistic activity. When the N-terminal region of the GR was exchanged with the respective domain of the progesterone receptor, STAT5-dependent transactivation was reduced at low and high expression levels. Only at high expression levels did the GR exhibit the properties of a coactivator and enhanced STAT5 activity in the absence of a functional DNA binding domain and of GR binding sites in the proximal region of the beta-casein gene promoter. Furthermore, at high GR expression levels RU486 was nearly as efficient as dexamethasone in activating transcription via the STAT5 dependent beta-casein gene promoter. The results reconcile the controversial issue regarding the DNA binding-independent action of the GR together with STAT5 and provide evidence that the mode of action of the GR depends not only on the type of the particular promoter at which it acts but also on the concentration of the GR. GR DNA binding function appears to be mandatory for beta-casein gene expression in mammary epithelial cells, since the promoter function is completely dependent on the integrity of GR binding sites in the promoter.

Nuclear factor-kappa B repression in antiinflammation and immunosuppression by glucocorticoids.

The transcription factor nuclear factor-kappaB (NF-kappaB) directs transcription of a large number of key molecules in immunological and inflammatory responses. The recently discovered inhibition of transcriptional activity of this factor by the activated glucocorticoid receptor (GR) provides a molecular basis for the potent antiinflammatory and immunosuppressive properties of glucocorticoids. This repressive activity of the GR can function independently of transcriptional activity. Because it has been shown that certain steroid receptor ligands can differentially address transactivation and transrepression functions, it may be possible to develop ligands that specifically suppress NF-kappaB activity and, as a result, are more efficient in treatment of a variety of important chronic inflammatory diseases with less severe side effects than those of currently available drugs.

High level of cannabinoid receptor 1, absence of regulator of G protein signalling 13 and differential expression of Cyclin D1 in mantle cell lymphoma.

Mantle cell lymphoma (MCL) is a moderately aggressive B-cell lymphoma that responds poorly to currently used therapeutic protocols. In order to identify tumour characteristics that improve the understanding of biology of MCL, analysis of oligonucleotide microarrays were used to define specific gene expression profiles. Biopsy samples of MCL cases were compared to reactive lymphoid tissue. Among genes differentially expressed in MCL were genes that are involved in the regulation of proliferation, cell signalling, adhesion and homing. Furthermore, some genes with previously unknown function, such as C11orf32, C2orf10, TBC1D9 and ABCA6 were found to be differentially expressed in MCL compared to reactive lymphoid tissue. Of special interest was the high expression of the cannabinoid receptor 1 (CB1) gene in all MCL cases analysed. These results were further confirmed at the cellular and protein level by immunocytochemical staining and immunoblotting of MCL cells. Furthermore, there was a reduced expression of a regulator of G protein signalling, RGS13 in all MCLs, with a complete absence in the majority of cases while present in control lymphoid tissue. These results were further confirmed by PCR. Sequencing of the RGS13 gene revealed changes suggesting polymorphisms, indicating that downregulation of the expression of RGS13 is not related to mutations, but may serve as a new specific marker for MCL. Moreover, comparison between individual cases of MCL, revealed that the CCND1 gene appears to be differently expressed in MCL cases with high vs low proliferative activity.

Negative cross-talk between RelA and the glucocorticoid receptor: a possible mechanism for the antiinflammatory action of glucocorticoids.

Glucocorticoids are efficient antiinflammatory agents, and their effects include transcriptional repression of several cytokines and adhesion molecules. Whereas glucocorticoids down-regulate the expression of genes relevant during inflammation, nuclear factor (NF)-kappa B/Rel proteins function as important positive regulators of these genes. The expression of intercellular adhesion molecule-1 (ICAM-1), which plays an essential role in recruitment and migration of leukocytes to sites of inflammation, is also down-regulated by glucocorticoids. We found that a functional NF-kappa B site in the ICAM-1 promoter, which can be activated by either 12-O-tetradecanoylphorbol-13-acetate or tumor necrosis factor-alpha (TNF alpha), is also the target for glucocorticoids. In this report we present evidence that the ligand-activated glucocorticoid receptor (GR) is able to repress RelA-mediated activation of the ICAM-1 NF-kappa B site. Conversely, transcriptional activation by GR via a glucocorticoid response element is specifically repressed by RelA, but not by other NF-kappa B/Rel family members. Mutational analysis of GR demonstrates that the DNA binding domain and the ligand binding domain are required for the functional repression of NF-kappa B activation. Despite the importance of the DNA binding domain, we found that the transcriptional repression of NF-kappa B, mediated by GR, is not caused by binding of GR to the ICAM-1 NF-kappa B element, but by a physical interaction between the GR and RelA protein. The repressive effect of GR on NF-kappa B-mediated activation was not shared by other steroid/thyroid receptors. Only the progesterone receptor, which belongs to the same subfamily as GR and which possesses high homology with GR, was able to repress NF-kappa B-mediated transcription. These studies highlight a possible molecular mechanism that can explain the antiinflammatory effects of glucocorticoid treatment during inflammation.

Glucocorticoid receptor lacking the tau 1 transactivation domain is a gene-specific regulator of the wild-type glucocorticoid-receptor activity.

The glucocorticoid receptor (GR) contains a major transactivation function (tau 1), located in the N-terminal domain. tau 1 contributes to about 80% of the ligand-inducible transcriptional activity of GR. In this study, we show that GR devoid of tau 1 (symbol: see text] GR) can inhibit activation of gene expression by wild-type GR but this does not occur for all target genes. Activation of the mouse mammary tumor virus promoter by wild-type GR in transiently transfected chinese hamster ovary (CHO) cells lacking endogenous GR was repressed by cotransfecting [symbol: see text] GR. This effect was proportional to the amount of transfected [symbol: see text] GR and was not due to squelching. A moderate expression level of stably transfected [symbol: see text] GR mutant was also shown to repress the transcriptional activity of endogenous GR present in rat skeletal myoblast L8 cells. Glucocorticoid mediated down regulation of endogenous GR gene expression can be blocked by the [symbol: see text] GR mutant in stably transfected L8 cells. In contrast, no inhibition was observed on glucocorticoid induction of the endogenous glutamine synthetase gene in L8 cells. However, glucocorticoid induction of a reporter gene driven by the chicken glutamine synthetase promoter was inhibited by [symbol: see text] GR in L8 cells. Stable expression of wild-type GR in CHO cells rendered the cells glucocorticoid responsive with regard to glutamine synthetase induction but coexpression of [symbol: see text] GR did not repress induction of the endogenous glutamine synthetase gene expression by wild-type GR. Expression of [symbol: see text] GR alone in CHO cells did not render the glutamine synthetase gene glucocorticoid responsive, indicating that [symbol: see text] GR has no transcriptional activity on the glutamine synthetase gene. We conclude from these results that the structure of glucocorticoid-response elements within target genes may be very critical for the ability of the mutant receptor to exhibit a dominant negative effect.

Glucocorticoid effects on NF-kappaB binding in the transcription of the ICAM-1 gene.

Glucocorticoid hormones are potent antiinflammatory drugs. A key mechanism in the antiinflammatory action is repression of the nuclear factor kappa B (NF-kappaB) signaling pathway. This results in transcriptional repression of inflammatory genes controlled by NF-kappaB, including the intercellular adhesion molecule-1 (ICAM-1). We have investigated expression levels, nuclear translocation and DNA binding of NF-kappaB in vitro and in vivo in U937 cells during activation and repression. Repression of NF-kappaB signaling by glucocorticoids does not prevent NF-kappaB translocation or DNA binding. However interestingly, in vivo foot printing of the NF-kappaB site in the ICAM-1 gene indicates that glucocorticoids change the conformation of the protein complex binding to the NF-kappaB site. These results suggests that NF-kappaB interaction with the glucocorticoid receptor does not displace NF-kappaB from its DNA binding site but rather changes the complex into a transcriptionally inert form.

A new function for the C-terminal zinc finger of the glucocorticoid receptor. Repression of RelA transactivation.

Glucocorticoids inhibit NF-kappaB signaling by interfering with the NF-kappaB transcription factor RelA. Previous studies have identified the DNA-binding domain (DBD) in the glucocorticoid receptor (GR) as the major region responsible for this repressive activity. Using GR mutants with chimeric DBDs the repressive function was found to be located in the C-terminal zinc finger. As predicted from these results the mineralocorticoid receptor that contains a C-terminal zinc finger identical to that of the GR was also able to repress RelA-dependent transcription. Mutation of a conserved arginine or a lysine in the second zinc finger of the GR DBD (Arg-488 or Lys-490 in the rat GR) abolished the ability of GR to inhibit RelA activity. In contrast, C-terminal zinc finger GR mutants with mutations in the dimerization box or mutations necessary for full transcriptional GR activity were still able to repress RelA-dependent transcription. In addition, we found that the steroid analog ZK98299 known to induce GR transrepression of AP-1 had no inhibitory effect on RelA activity. In summary, these results demonstrate that the inhibition of NF-kappaB by glucocorticoids involves two critical amino acids in the C-terminal zinc finger of the GR. Furthermore, the results from the use of mineralocorticoid receptor and anti-glucocorticoids suggest that the mechanisms for GR-mediated repression of NF-kappaB and AP-1 are different.