myGRN: a database and visualisation system for the storage and analysis of developmental genetic regulatory networks.

BACKGROUND: Biological processes are regulated by complex interactions between transcription factors and signalling molecules, collectively described as Genetic Regulatory Networks (GRNs). The characterisation of these networks to reveal regulatory mechanisms is a long-term goal of many laboratories. However compiling, visualising and interacting with such networks is non-trivial. Current tools and databases typically focus on GRNs within simple, single celled organisms. However, data is available within the literature describing regulatory interactions in multi-cellular organisms, although not in any systematic form. This is particularly true within the field of developmental biology, where regulatory interactions should also be tagged with information about the time and anatomical location of development in which they occur. DESCRIPTION: We have developed myGRN (http://www.myGRN.org), a web application for storing and interrogating interaction data, with an emphasis on developmental processes. Users can submit interaction and gene expression data, either curated from published sources or derived from their own unpublished data. All interactions associated with publications are publicly visible, and unpublished interactions can only be shared between collaborating labs prior to publication. Users can group interactions into discrete networks based on specific biological processes. Various filters allow dynamic production of network diagrams based on a range of information including tissue location, developmental stage or basic topology. Individual networks can be viewed using myGRV, a tool focused on displaying developmental networks, or exported in a range of formats compatible with third party tools. Networks can also be analysed for the presence of common network motifs. We demonstrate the capabilities of myGRN using a network of zebrafish interactions integrated with expression data from the zebrafish database, ZFIN. CONCLUSION: Here we are launching myGRN as a community-based repository for interaction networks, with a specific focus on developmental networks. We plan to extend its functionality, as well as use it to study networks involved in embryonic development in the future.

Cannabidivarin completely rescues cognitive deficits and delays neurological and motor defects in male Mecp2 mutant mice.

BACKGROUND: Recent evidence suggests that 2-week treatment with the non-psychotomimetic cannabinoid cannabidivarin (CBDV) could be beneficial towards neurological and social deficits in early symptomatic Mecp2 mutant mice, a model of Rett syndrome (RTT). AIM: The aim of this study was to provide further insights into the efficacy of CBDV in Mecp2-null mice using a lifelong treatment schedule (from 4 to 9 weeks of age) to evaluate its effect on recognition memory and neurological defects in both early and advanced stages of the phenotype progression. METHODS: CBDV 0.2, 2, 20 and 200 mg/kg/day was administered to Mecp2-null mice from 4 to 9 weeks of age. Cognitive and neurological defects were monitored during the whole treatment schedule. Biochemical analyses were carried out in brain lysates from 9-week-old wild-type and knockout mice to evaluate brain-derived neurotrophic factor (BDNF) and insulin-like growth factor-1 (IGF-1) levels as well as components of the endocannabinoid system. RESULTS: CBDV rescues recognition memory deficits in Mecp2 mutant mice and delays the appearance of neurological defects. At the biochemical level, it normalizes BDNF/IGF1 levels and the defective PI3K/AKT/mTOR pathway in Mecp2 mutant mice at an advanced stage of the disease. Mecp2 deletion upregulates CB1 and CB2 receptor levels in the brain and these changes are restored after CBDV treatment. CONCLUSIONS: CBDV administration exerts an enduring rescue of memory deficits in Mecp2 mutant mice, an effect that is associated with the normalization of BDNF, IGF-1 and rpS6 phosphorylation levels as well as CB1 and CB2 receptor expression. CBDV delays neurological defects but this effect is only transient.

Polypharmacology Shakes Hands with Complex Aetiopathology.

Chronic diseases are due to deviations of fundamental physiological systems, with different pathologies being characterised by similar malfunctioning biological networks. The ensuing compensatory mechanisms may weaken the body's dynamic ability to respond to further insults and reduce the efficacy of conventional single target treatments. The multitarget, systemic, and prohomeostatic actions emerging for plant cannabinoids exemplify what might be needed for future medicines. Indeed, two combined cannabis extracts were approved as a single medicine (Sativex(®)), while pure cannabidiol, a multitarget cannabinoid, is emerging as a treatment for paediatric drug-resistant epilepsy. Using emerging cannabinoid medicines as an example, we revisit the concept of polypharmacology and describe a new empirical model, the 'therapeutic handshake', to predict efficacy/safety of compound combinations of either natural or synthetic origin.

Inflammatory modulation of exercise salience: using hormesis to return to a healthy lifestyle.

Most of the human population in the western world has access to unlimited calories and leads an increasingly sedentary lifestyle. The propensity to undertake voluntary exercise or indulge in spontaneous physical exercise, which might be termed "exercise salience", is drawing increased scientific attention. Despite its genetic aspects, this complex behaviour is clearly modulated by the environment and influenced by physiological states. Inflammation is often overlooked as one of these conditions even though it is known to induce a state of reduced mobility. Chronic subclinical inflammation is associated with the metabolic syndrome; a largely lifestyle-induced disease which can lead to decreased exercise salience. The result is a vicious cycle that increases oxidative stress and reduces metabolic flexibility and perpetuates the disease state. In contrast, hormetic stimuli can induce an anti-inflammatory phenotype, thereby enhancing exercise salience, leading to greater biological fitness and improved functional longevity. One general consequence of hormesis is upregulation of mitochondrial function and resistance to oxidative stress. Examples of hormetic factors include calorie restriction, extreme environmental temperatures, physical activity and polyphenols. The hormetic modulation of inflammation, and thus, exercise salience, may help to explain the highly heterogeneous expression of voluntary exercise behaviour and therefore body composition phenotypes of humans living in similar obesogenic environments.