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Background Bariatric surgery remains the most effective therapy for adiposity reduction and remission of type 2 diabetes. Although different bariatric procedures associate with pronounced shifts in the gut microbiota, their functional role in the regulation of energetic and metabolic benefits achieved with the surgery are not clear. Methods To evaluate the causal as well as the inherent therapeutic character of the surgery-altered gut microbiome in improved energy and metabolic control in diet-induced obesity, an antibiotic cocktail was used to eliminate the gut microbiota in diet-induced obese rats after gastric bypass surgery, and gastric bypass-shaped gut microbiota was transplanted into obese littermates. Thorough metabolic profiling was combined with omics technologies on samples collected from cecum and plasma to identify adaptions in gut microbiota-host signaling, which control improved energy balance and metabolic profile after surgery. Results In this study, we first demonstrate that depletion of the gut microbiota largely reversed the beneficial effects of gastric bypass surgery on negative energy balance and improved glucolipid metabolism. Further, we show that the gastric bypass-shaped gut microbiota reduces adiposity in diet-induced obese recipients by re-activating energy expenditure from metabolic active brown adipose tissue. These beneficial effects were linked to improved glucose homeostasis, lipid control, and improved fatty liver disease. Mechanistically, these effects were triggered by modulation of taurine metabolism by the gastric bypass gut microbiota, fostering an increased abundance of intestinal and circulating taurine-conjugated bile acid species. In turn, these bile acids activated gut-restricted FXR and systemic TGR5 signaling to stimulate adaptive thermogenesis. Conclusion Our results establish the role of the gut microbiome in the weight loss and metabolic success of gastric bypass surgery. We here identify a signaling cascade that ent

Although all tumours are rare in childhood, there are some particularly rare paediatric cancers which have not benefited from advances made by the international paediatric oncology network. To establish a shared definition and produce a list of these entities, the European Union Joint Action on Rare Cancers (JARC) promoted a consensus effort. The definition was based on the incidence rates estimated using the information network on rare cancers (RARECAREnet) database, pooling data from 94 population-based cancer registries and 27 countries. The RARECAREnet list of cancers was used to estimate the incidence rates. This list groups cancers by combining the International Classification of Diseases for Oncology, third edition, morphology and topography codes. According to the consensus, very rare paediatric cancers were identified as those with an annual incidence <2/1000000 and corresponded to 11% of all cancers in patients aged 0–14 years. Two subgroups were identified: tumour types typical of childhood (i.e. hepatoblastoma, pleuropulmonary blastoma, pancreatoblastoma) and those typical of adult age (i.e. carcinomas, melanoma). The threshold of 2/1000000 could also be adopted in populations aged 0–19 years: in this case, three tumour types had an incidence rate which was >2/1000000 (i.e. thyroid and testicular cancers and skin melanoma), but the consensus experts considered them as ‘very rare’ according to their clinical needs (e.g. shortage of knowledge and clinical expertise as the other rare paediatric cancers). The JARC consensus produced a definition and a list of very rare paediatric cancers which may represent a starting point for prioritising research on these tumours, based on data and patients’ clinical needs.

BACKGROUND: A membrane-penetrating cation, dodecyltriphenylphosphonium (C12TPP), facilitates the recycling of fatty acids in the artificial lipid membrane and mitochondria. C12TPP can dissipate mitochondrial membrane potential and may affect total energy expenditure and body weight in animals and humans. METHODS: We investigated the metabolic effects of C12TPP in isolated brown-fat mitochondria, brown adipocyte cultures and mice in vivo. Experimental approaches included the measurement of oxygen consumption, carbon dioxide production, western blotting, magnetic resonance imaging and bomb calorimetry. RESULTS: In mice, C12TPP (50 mu mol per (day.kg body weight)) in the drinking water significantly reduced body weight (12%, P<0.001) and body fat mass (24%, P<0.001) during the first 7 days of treatment. C12TPP did not affect water palatability and intake or the energy and lipid content in feces. The addition of C12TPP to isolated brown-fat mitochondria resulted in increased oxygen consumption. Three hours of pretreatment with C12TPP also increased oligomycin-insensitive oxygen consumption in brown adipocyte cultures (P<0.01). The effects of C12TPP on mitochondria, cells and mice were independent of uncoupling protein 1 (UCP1). However, C12TPP treatment increased the mitochondrial protein levels in the brown adipose tissue of both wild-type and UCP1-knockout mice. Pair-feeding revealed that one-third of the body weight loss in C12TPP-treated mice was due to reduced food intake. C12TPP treatment elevated the resting metabolic rate (RMR) by up to 18% (P<0.05) compared with pair-fed animals. C12TPP reduced the respiratory exchange ratio, indicating enhanced fatty acid oxidation in mice. CONCLUSIONS: C12TPP combats diet-induced obesity by reducing food intake, increasing the RMR and enhancing fatty acid oxidation.

Recent studies on mouse and human skeletal muscle (SM) demonstrated the important link between mitochondrial function and the cellular metabolic adaptation. To identify key compensatory molecular mechanisms in response to chronic mitochondrial distress, we analyzed mice with ectopic SM respiratory uncoupling in uncoupling protein 1 transgenic (UCP1-TG) mice as model of muscle-specific compromised mitochondrial function. Here we describe a detailed metabolic reprogramming profile associated with mitochondrial perturbations in SM, triggering an increased protein turnover and amino acid metabolism with induced biosynthetic serine/1-carbon/glycine pathway and the longevity-promoting polyamine spermidine as well as the trans-sulfuration pathway. This is related to an induction of NADPH-generating pathways and glutathione metabolism as an adaptive mitohormetic response and defense against increased oxidative stress. Strikingly, consistent muscle retrograde signaling profiles were observed in acute stress states such as muscle cell starvation and lipid overload, muscle regeneration, and heart muscle inflammation, but not in response to exercise. We provide conclusive evidence for a key compensatory stress-signaling network that preserves cellular function, oxidative stress tolerance, and survival during conditions of increased SM mitochondrial distress, a metabolic reprogramming profile so far only demonstrated for cancer cells and heart muscle.-Ost, M., Keipert, S., van Schothorst, E. M., Donner, V., van der Stelt, I., Kipp, A. P., Petzke, K.-J., Jove, M., Pamplona, R., Portero-Otin, M., Keijer, J., and Klaus, S. Muscle mitohormesis promotes cellular survival via serine/glycine pathway flux., Recent studies on mouse and human skeletal muscle (SM) demonstrated the important link between mitochondrial function and the cellular metabolic adaptation. To identify key compensatory molecular mechanisms in response to chronic mitochondrial distress, we analyzed mice with ectopic SM respiratory uncoupling in uncoupling protein 1 transgenic (UCP1-TG) mice as model of muscle-specific compromised mitochondrial function. Here we describe a detailed metabolic reprogramming profile associated with mitochondrial perturbations in SM, triggering an increased protein turnover and amino acid metabolism with induced biosynthetic serine/1-carbon/glycine pathway and the longevity-promoting polyamine spermidine as well as the trans-sulfuration pathway. This is related to an induction of NADPH-generating pathways and glutathione metabolism as an adaptive mitohormetic response and defense against increased oxidative stress. Strikingly, consistent muscle retrograde signaling profiles were observed in acute stress states such as muscle cell starvation and lipid overload, muscle regeneration, and heart muscle inflammation, but not in response to exercise. We provide conclusive evidence for a key compensatory stress-signaling network that preserves cellular function, oxidative stress tolerance, and survival during conditions of increased SM mitochondrial distress, a metabolic reprogramming profile so far only demonstrated for cancer cells and heart muscle.-Ost, M., Keipert, S., van Schothorst, E. M., Donner, V., van der Stelt, I., Kipp, A. P., Petzke, K.-J., Jove, M., Pamplona, R., Portero-Otin, M., Keijer, J., and Klaus, S. Muscle mitohormesis promotes cellular survival via serine/glycine pathway flux.

Sex allocation theory predicts that females should bias their reproductive investment towards the sex generating the greatest fitness returns. The fitness of male offspring is often more dependent upon maternal investment, and therefore, high-quality mothers should invest in sons. However, the local resource competition hypothesis postulates that when offspring quality is determined by maternal quality or when nest site and maternal quality are related, high-quality females should invest in the philopatric sex. Waterfowl showing male-biased size dimorphism but female-biased philopatry are ideal for differentiating between these alternatives. We utilized molecular sexing methods and high-resolution maternity tests to study the occurrence and fitness consequences of facultative sex allocation in Barrow's goldeneyes (Bucephala islandica). We determined how female structural size, body condition, nest-site safety and timing of reproduction affected sex allocation and offspring survival. We found that the overall sex ratio was unbiased, but in line with the local resource competition hypothesis, larger females produced female-biased broods and their broods survived better than those of smaller females. This bias occurred despite male offspring being larger and tending to have lower post-hatching survival. The species shows strong female breeding territoriality, so the benefit of inheriting maternal quality by philopatric daughters may exceed the potential mating benefit for sons of high-quality females. [KEYWORDS: local resource competition conspecific nest parasitism common goldeneye ratio variation bucephala-islandica natural-selection natal philopatry red deer birds size], Sex allocation theory predicts that females should bias their reproductive investment towards the sex generating the greatest fitness returns. The fitness of male offspring is often more dependent upon maternal investment, and therefore, high-quality mothers should invest in sons. However, the local resource competition hypothesis postulates that when offspring quality is determined by maternal quality or when nest site and maternal quality are related, high-quality females should invest in the philopatric sex. Waterfowl showing male-biased size dimorphism but female-biased philopatry are ideal for differentiating between these alternatives. We utilized molecular sexing methods and high-resolution maternity tests to study the occurrence and fitness consequences of facultative sex allocation in Barrow's goldeneyes (Bucephala islandica). We determined how female structural size, body condition, nest-site safety and timing of reproduction affected sex allocation and offspring survival. We found that the overall sex ratio was unbiased, but in line with the local resource competition hypothesis, larger females produced female-biased broods and their broods survived better than those of smaller females. This bias occurred despite male offspring being larger and tending to have lower post-hatching survival. The species shows strong female breeding territoriality, so the benefit of inheriting maternal quality by philopatric daughters may exceed the potential mating benefit for sons of high-quality females. [KEYWORDS: local resource competition conspecific nest parasitism common goldeneye ratio variation bucephala-islandica natural-selection natal philopatry red deer birds size]