Aging and Circadian Disruption: Causes and Effects

The relationship between aging and daily “circadian” behavior in humans is bidirectional: on the one hand, dysfunction of circadian clocks promotes age-related maladies; on the other, aging per se leads to changes and disruption in circadian behavior and physiology. For the latter case, recent research suggests that changes to both homeostatic and circadian sleep regulatory mechanisms may play a role. Could hormonal changes be in part responsible

A renewable energy-centred research agenda for planning and financing Nexus development objectives in rural sub-Saharan Africa

In rural sub-Saharan Africa – the global poverty hotspot – the vast majority of cropland is rainfed only, resulting in reduced and unstable yields. Smallholder farmers account for 80% of agricultural production but they have limited access to relevant services to support both commercial operations and their livelihoods: more than two-thirds of rural dwellers have no access to electricity (crucial for crop irrigation, processing, and storage) and about 40% have no access to clean water. Previous research has analysed integrated technological and resource management approaches to tackle these overlapping development gaps. To finance and implement such transformations in resource-constrained settings, it is now crucial to understand the business and investment implications, also considering the strong regional population growth and the increasing frequency and intensity of climate extremes. Here, we lay out a research agenda that promotes the integration of multi-scale modelling excellence along the climate-water-renewable energy-agriculture-development Nexus and the creation of robust business models for private companies that can sustainably support private smallholder farmers of SSAin their effort to eradicate poverty and inequality. The proposed agenda is a cornerstone of the EC-H2020 project LEAP-RE RE4AFAGRI (“Renewable Energy for African Agriculture: Integrating Modelling Excellence and Robust Business Models”). In proposing the agenda, we highlight the importance of integrating energy access into the Nexus framework from both research and investment perspectives

Sleep duration and quality are not associated with brown adipose tissue volume or activity—as determined by 18F-FDG uptake, in young, sedentary adults

Study Objectives: Short sleep duration and sleep disturbances have been related to obesity and metabolic disruption. However, the behavioral and physiological mechanisms linking sleep and alterations in energy balance and metabolism are incompletely understood. In rodents, sleep regulation is closely related to appropriate brown adipose tissue (BAT) thermogenic activity, but whether the same is true in humans has remained unknown. The present work examines whether sleep duration and quality are related to BAT volume and activity (measured by 18F-FDG) and BAT radiodensity in humans. Methods: A total of 118 healthy adults (69% women, 21.9 ± 2.2 years, body mass index: 24.9 ± 4.7 kg/m2) participated in this cross-sectional study. Sleep duration and other sleep variables were measured using a wrist-worn accelerometer for seven consecutive days for 24 hours per day. The Pittsburgh Sleep Quality Index was used to assess sleep quality. All participants then underwent a personalized cold exposure to determine their BAT volume, activity, and radiodensity (a proxy of the intracellular triglyceride content), using static positron emission tomography combined with computed tomography (PET/CI) scan. Results: Neither sleep duration nor quality was associated with BAT volume or activity (the latter represented by the mean and peak standardized 18F-FDG uptake values) or radiodensity (all p > .1). The lack of association remained after adjusting the analyses for sex, date of PET/CT, and body composition. Conclusions: Although experiments in rodent models indicate a strong relationship to exist between sleep regulation and BAT function, it seems that sleep duration and quality may not be directly related to the BAT variables examined in the present work

A renewable energy-centred research agenda for planning and financing Nexus development objectives in rural sub-Saharan Africa

In rural sub-Saharan Africa – the global poverty hotspot – the vast majority of cropland is rainfed only, resulting in reduced and unstable yields. Smallholder farmers account for 80% of agricultural production but they have limited access to relevant services to support both commercial operations and their livelihoods: more than two-thirds of rural dwellers have no access to electricity (crucial for crop irrigation, processing, and storage) and about 40% have no access to clean water. Previous research has analysed integrated technological and resource management approaches to tackle these overlapping development gaps. To finance and implement such transformations in resource-constrained settings, it is now crucial to understand the business and investment implications, also considering the strong regional population growth and the increasing frequency and intensity of climate extremes. Here, we lay out a research agenda that promotes the integration of multi-scale modelling excellence along the climate-water-renewable energy-agriculture-development Nexus and the creation of robust business models for private companies that can sustainably support private smallholder farmers of SSAin their effort to eradicate poverty and inequality. The proposed agenda is a cornerstone of the EC-H2020 project LEAP-RE RE4AFAGRI (“Renewable Energy for African Agriculture: Integrating Modelling Excellence and Robust Business Models”). In proposing the agenda, we highlight the importance of integrating energy access into the Nexus framework from both research and investment perspectives

Temporal orchestration of circadian autophagy rhythm by C/EBPβ

Temporal organization of tissue metabolism is important for maintaining nutrient and energy homeostasis in mammals. Autophagy is a conserved cellular pathway that is activated in response to nutrient limitation, resulting in the degradation of cytoplasmic components and the release of amino acids and other nutrients. Here, we show that autophagy exhibits robust circadian rhythm in mouse liver, which is accompanied by cyclic induction of genes involved in various steps of autophagy. Functional analyses of transcription factors and cofactors identified C/EBPβ as a potent activator of autophagy. C/EBPβ is rhythmically expressed in the liver and is regulated by both circadian and nutritional signals. In cultured primary hepatocytes, C/EBPβ stimulates the program of autophagy gene expression and is sufficient to activate autophagic protein degradation. Adenoviral-mediated RNAi knockdown of C/EBPβ in vivo abolishes diurnal autophagy rhythm in the liver. Further, circadian regulation of C/EBPβ and autophagy is disrupted in mice lacking a functional liver clock. We have thus identified C/EBPβ as a key factor that links autophagy to biological clock and maintains nutrient homeostasis throughout light/dark cycles

Neuroendocrinology of Sleep and Wakefulness

SCOPUS: ch.binfo:eu-repo/semantics/publishe

Contribution à l'étude de la sécrétion de cortisol chez l'homme

Doctorat en sciences médicalesinfo:eu-repo/semantics/nonPublishe

Contribution à l'étude de la sécrétion de cortisol chez l'homme

Doctorat en sciences médicalesinfo:eu-repo/semantics/nonPublishe