Novel paracrine/autocrine roles of prostaglandins in the human ovary.

Prostaglandin (PG)E2 and PGF2α exert important roles in ovulation and luteinisation. The studies reported herein have used human granulosa-lutein cells to investigate: (1) the relationship between basal PG and progesterone production; (2) participation of PGs in the steroidogenic response to high-density-lipoproteins (HDL); (3) the role for PGs in controlling ovarian cortisol metabolism by 11β-hydroxysteroid dehydrogenase (11β- HSD); (4) the role of EP1 and EP2 receptors in mediating ovarian responses to PGE2. In culture, basal PG production decreased with a concomitant rise in progesterone synthesis. However, meclofenamic acid suppressed both PGE2 and PGF2α output without affecting progesterone production, and aminoglutethimide inhibited progesterone production without affecting either PG concentration. Both HDL and apolipoprotein A-I increased PGE2, cAMP and progesterone concentrations. Each of these effects was abolished by co-treatment with meclofenamic acid. Meclofenamic acid, indomethacin and niflumic acid each suppressed ovarian cortisol oxidation, whereas co-treatment with PGE2, PGD2 and PGF2α each increased 11β-HSD activities. Human follicular fluid was confirmed to contain intrinsic aqueous stimuli and hydrophobic inhibitors of NADP+-dependent 11β-HSD activity that eluted from C18 mini-columns at 0-10% and 65-90% (v/v) methanol, respectively. PGE2, PGp2α and 6-keto-PGF1α each eluted at 20-50% (v/v) methanol. The ability of PGE2 to stimulate progesterone production was inhibited by SC19220 and abolished by AH6809 (preferential EP1 and EP2 antagonists respectively). While SC19220 had no significant effect on the stimulation of cAMP accumulation and 11β-HSD activity by PGE2, these effects were abolished by co-treatment with AH6809. In conclusion, while changes in the ouput of PGs and progesterone in luteinizing human granulosa cells appeared to occur independently of each other, PGs were implicated in the steroidogenic actions of HDL and apolipoprotein A-I. Locally synthesised PGs appear to maintain ovarian 11β-HSD activity but do not contribute to the hydrophilic stimuli of 11β-HSD activity present in follicular fluid. Both EP1 and EP2 receptors appear to participate in the stimulation of progesterone synthesis, cAMP accumulation and 11β-HSD activity by PGE2

Mouse Resource Browser--a database of mouse databases.

The laboratory mouse has become the organism of choice for discovering gene function and unravelling pathogenetic mechanisms of human diseases through the application of various functional genomic approaches. The resulting deluge of data has led to the deployment of numerous online resources and the concomitant need for formalized experimental descriptions, data standardization, database interoperability and integration, a need that has yet to be met. We present here the Mouse Resource Browser (MRB), a database of mouse databases that indexes 217 publicly available mouse resources under 22 categories and uses a standardised database description framework (the CASIMIR DDF) to provide information on their controlled vocabularies (ontologies and minimum information standards), and technical information on programmatic access and data availability. Focusing on interoperability and integration, MRB offers automatic generation of downloadable and re-distributable SOAP application-programming interfaces for resources that provide direct database access. MRB aims to provide useful information to both bench scientists, who can easily navigate and find all mouse related resources in one place, and bioinformaticians, who will be provided with interoperable resources containing data which can be mined and integrated. Database URL: http://bioit.fleming.gr/mrb

Finding and sharing: new approaches to registries of databases and services for the biomedical sciences

The recent explosion of biological data and the concomitant proliferation of distributed databases make it challenging for biologists and bioinformaticians to discover the best data resources for their needs, and the most efficient way to access and use them. Despite a rapid acceleration in uptake of syntactic and semantic standards for interoperability, it is still difficult for users to find which databases support the standards and interfaces that they need. To solve these problems, several groups are developing registries of databases that capture key metadata describing the biological scope, utility, accessibility, ease-of-use and existence of web services allowing interoperability between resources. Here, we describe some of these initiatives including a novel formalism, the Database Description Framework, for describing database operations and functionality and encouraging good database practise. We expect such approaches will result in improved discovery, uptake and utilization of data resources. Database URL: http://www.casimir.org.uk/casimir_dd

Models for financial sustainability of biological databases and resources

Following the technological advances that have enabled genome-wide analysis in most model organisms over the last decade, there has been unprecedented growth in genomic and post-genomic science with concomitant generation of an exponentially increasing volume of data and material resources. As a result, numerous repositories have been created to store and archive data, organisms and material, which are of substantial value to the whole community. Sustained access, facilitating re-use of these resources, is essential, not only for validation, but for re-analysis, testing of new hypotheses and developing new technologies/platforms. A common challenge for most data resources and biological repositories today is finding financial support for maintenance and development to best serve the scientific community. In this study we examine the problems that currently confront the data and resource infrastructure underlying the biomedical sciences. We discuss the financial sustainability issues and potential business models that could be adopted by biological resources and consider long term preservation issues within the context of mouse functional genomics efforts in Europe

Activation of Phosphatidylinositol 3-Kinase/Protein Kinase B by Corticotropin-Releasing Factor in Human Monocytes

Corticotropin-releasing factor (CRF) exerts proinflammatory effects in peripheral tissues, whereas the intracellular pathways mediating these effects have not been completely characterized yet. We have previously shown that CRF induces nuclear factor-κB DNA-binding activity in mouse and human leukocytes. Here we demonstrate that in the human monocytic THP-1 cells, CRF activates the phosphatidylinositol 3-kinase (PI3K)/Akt and ERK1/2 pathways. These effects of CRF are mediated by corticotropin-releasing factor receptor 2 (CRF2), as suggested by their abolishment after treatment with the specific CRF2 antagonist, astressin 2B. The CRF-mediated PI3K/Akt activation induces cell survival as suggested by the stimulation of the antiapoptotic factor Bcl-2. ERK1/2 activation results in up-regulation of IL-8 expression, an effect inhibited by the CRF-induced activation of PI3K/Akt. These studies demonstrate novel effects of CRF in human monocytes mediated by the activation of PI3K/Akt. Moreover, they reveal pathway-specific effects of the CRF/CRF2 system in chemokine activation and cell survival that may be of importance for the development of novel therapeutics for inflammatory diseases