Age and Diet Affect Gene Expression Profile in Canine Skeletal Muscle

We evaluated gene transcription in canine skeletal muscle (biceps femoris) using microarray analysis to identify effects of age and diet on gene expression. Twelve female beagles were used (six 1-year olds and six 12-year olds) and they were fed one of two experimental diets for 12 months. One diet contained primarily plant-based protein sources (PPB), whereas the second diet contained primarily animal-based protein sources (APB). Affymetrix GeneChip Canine Genome Arrays were used to hybridize extracted RNA. Age had the greatest effect on gene transcription (262 differentially expressed genes), whereas the effect of diet was relatively small (22 differentially expressed genes). Effects of age (regardless of diet) were most notable on genes related to metabolism, cell cycle and cell development, and transcription function. All these genes were predominantly down-regulated in geriatric dogs. Age-affected genes that were differentially expressed on only one of two diets were primarily noted in the PPB diet group (144/165 genes). Again, genes related to cell cycle (22/35) and metabolism (15/19) had predominantly decreased transcription in geriatric dogs, but 6/8 genes related to muscle development had increased expression. Effects of diet on muscle gene expression were mostly noted in geriatric dogs, but no consistent patterns in transcription were observed. The insight these data provide into gene expression profiles of canine skeletal muscle as affected by age, could serve as a foundation for future research pertaining to age-related muscle diseases

Lifestyle risk factors for obsessive-compulsive symptoms and related phenomena: What should lifestyle interventions target?

Objective: Understanding the impact of lifestyle on mental illness symptoms is important for informing psycho-education and developing interventions which target mental and physical comorbidities. Obsessive-compulsive and related disorders can have a significant impact on health-related quality of life and physical health. However, our understanding of the impact of lifestyle on obsessive-compulsive symptoms and broader compulsive and impulsive problematic repetitive behaviours is limited. Aims: We investigated whether lifestyle factors predicted change in obsessive-compulsive symptoms and problematic repetitive behaviours in a general population sample over a 3-month period. Methods: Eight hundred thirty-five participants completed an online questionnaire battery assessing lifestyle and mental health. Of these, 538 participants completed the same battery 3&thinsp;months later. We conducted negative binomial regressions to analyse the association of lifestyle factors at baseline with future (1) obsessive-compulsive symptoms, (2) compulsive problematic repetitive behaviours and (3) impulsive problematic repetitive behaviours, adjusting for baseline obsessive-compulsive symptoms and problematic repetitive behaviours. Results: Lower vegetable ( p&thinsp;=&thinsp;0.020) and oily fish ( p&thinsp;=&thinsp;0.040) intake and lower moderate intensity physical activity ( p&thinsp;=&thinsp;0.008) predicted higher obsessive-compulsive symptoms at follow-up. Higher intake of high-fat foods ( p&thinsp;&lt;&thinsp;0.001) predicted higher compulsive problematic repetitive behaviours at follow-up. No lifestyle factors significantly predicted impulsive problematic repetitive behaviours at follow-up. Conclusion: Our results speak to the potential importance of lifestyle quality screening, education and lifestyle interventions (e.g. an anti-inflammatory diet) for individuals experiencing compulsivity-related behaviours and/or symptoms. Further research into potential mechanisms of action will allow for more targeted approaches to lifestyle interventions for transdiagnostic compulsive behaviours. </jats:sec

The overwintering of Antarctic krill, Euphausia superba, from an ecophysiological perspective

A major aim of this review is to determine which physiological functions are adopted by adults and larvae to survive the winter season with low food supply and their relative importance. A second aim is to clarify the extent to which seasonal variation in larval and adult krill physiology is mediated by environmental factors with a strong seasonality, such as food supply or day light. Experimental studies on adult krill have demonstrated that speciWc physiological adaptations during autumn and winter, such as reduced metabolic rates and feeding activity, are not caused simply by the scarcity of food, as was previously assumed. These adaptations appear to be inXuenced by the local light regime. The physiological functions that larval krill adopt during winter (reduced metabolism, delayed development, lipid utilisation, and variable growth rates) are, in contrast to the adults, under direct control by the available food supply. During winter, the adults often seem to have little association with sea ice (at least until early spring). The larvae, however, feed within sea ice but mainly on the grazers of the ice algal community rather than on the algae themselves. In this respect, a miss-match in timing of the occurrence of the last phytoplankton blooms in autumn and the start of the sea ice formation, as has been increasingly observed in the west Antarctic Peninsula (WAP) region, will impact larval krill development during winter in terms of food supply and consequently the krill stock in this region

Prospects for a sustainable increase in the availability of long chain omega 3s: lessons from the Antarctic krill fishery.

• The global summit on nutrition, health and human behaviour (GSNHHB) identified the objective of increasing “the availability of long chain Omega‐3 (especially docosahexaenoic acid) for human consumption in a sustainable, environmentally responsible way”. • The objectives of management for sustainability include maintaining continuity of supply and limiting negative impacts. These objectives have associated challenges which are best illustrated using a case study. • Marine fisheries are likely to remain the main source of docosahexaenoic acid (DHA) for the foreseeable future. I use the example of the Antarctic krill fishery, which is a minor but high value source of DHA, to illustrate the issues, processes, actors and risks involved in attempting to manage natural resources in a sustainable, environmentally responsible way. • One of the key issues is uncertainty: The natural state of ecosystems, how they respond to exploitation, and how these responses will be affected by environmental change are not clearly understood. The solution is to use “precautionary” measures, which often means catching less than is theoretically possible, and additional restrictions on where the fishery can operate. • The “sustainability” of the Antarctic krill fishery has been questioned in a way that has impacted the delivery of Antarctic krill products to consumers. In reality, the fishery is one of only 3% of fisheries worldwide that the Food and Agriculture Organisation of the United Nations considers “under-exploited” and one of the few that have a management approach committed to limiting impacts on the both the target stock and the wider ecosystem. Disagreement arises partly because there is no universal agreement about the definitions of “sustainable” and “environmentally responsible” or about the standards of evidence required to support a claim. A potential solution is to identify the different objectives that people have for the ecosystem, and to agree acceptable trade-offs, levels of risk, and standards of evidence. This approach is compatible with the ecosystem approach to fisheries recommended by the 2002 World Summit on Sustainable Development. • The GSNHHB’s commitment to sustainability is a positive step which should be followed by engagement with suppliers to support the appropriate management and recovery of fished ecosystems. • GSNHHB’s objectives imply an increase in supply beyond the capacity of marine fisheries and therefore the development of alternative sources. • The steps towards sustainability are similar for all sources. They include identifying the different objectives that people have for the source ecosystem, evaluating the risks of not achieving these objectives, establishing trade-offs between objectives, and ensuring appropriate monitoring. It is essential for groups with an interest in source ecosystems to work with each other, and with scientists and managers, to achieve these steps