A5070721707- Circadian rhythm and melatonin
- Bat Biology and Ecology Studies
- Adipose Tissue and Metabolism
- Regulation of Appetite and Obesity
- Physiological and biochemical adaptations
- Thyroid Disorders and Treatments
- Spaceflight effects on biology
- Growth Hormone and Insulin-like Growth Factors
- Effects of Environmental Stressors on Livestock
- Adipokines, Inflammation, and Metabolic Diseases
- Sleep and Wakefulness Research
- DNA and Nucleic Acid Chemistry
- Neuroendocrine regulation and behavior
- Pancreatic function and diabetes
- Lung Cancer Research Studies
- Biochemical Analysis and Sensing Techniques
- Neurobiology and Insect Physiology Research
- Neuroscience of respiration and sleep
- Birth, Development, and Health
- Fungal Infections and Studies
- thermodynamics and calorimetric analyses
- RNA Interference and Gene Delivery
- Exercise and Physiological Responses
- Immune Response and Inflammation
- Neurogenesis and neuroplasticity mechanisms
Universität Ulm
2017-2024
Institute of Neurobiology
2019
Universität Hamburg
2012-2017
Museum am Rothenbaum
2015-2017
University of Aberdeen
2009-2014
Bavarian State Collection of Zoology
2006-2007
Institut des Neurosciences Cellulaires et Intégratives
2006-2007
University of Veterinary Medicine Hannover, Foundation
2007
Centre National de la Recherche Scientifique
2005-2007
University of Veterinary Medicine Vienna
2007
Prevalence of obesity among infants and children below 5 years age is rising dramatically, early childhood a forerunner obesity-associated diseases in adulthood. Childhood hence one the most serious public health challenges today. Here, we have identified mother-to-child lipid signaling that protects from obesity. We found breast milk-specific species, so-called alkylglycerol-type (AKG-type) ether lipids, which are absent infant formula adult-type diets, maintain beige adipose tissue (BeAT)...
Hibernation is a fascinating, yet enigmatic, physiological phenomenon during which body temperature and metabolism are reduced to save energy. During the harsh season, this strategy allows substantial energy saving by reducing metabolism. Accordingly, biological processes considerably slowed down minimum. However, persistence of temperature-compensated, functional clock in hibernating mammals has long been debated. Here, we show that master circadian no longer displays 24-h molecular...
Hibernation is an energy-conserving behavior consisting of periods inhibited metabolism (‘torpor’) with lowered body temperature. Torpor bouts are interspersed by arousal periods, in which increases and temperature returns to euthermia. In deep torpor, the typically decreases 2–10 °C, major physiological immunological changes occur. One these alterations constitutes almost complete depletion circulating lymphocytes that reversed rapidly upon arousal. Here we show torpor induces storage...
In the adult brain, leptin regulates energy homeostasis primarily via hypothalamic circuitry that affects food intake and expenditure. Evidence from rodent models has demonstrated during early postnatal life, is relatively ineffective in modulating these pathways, despite high circulating levels presence of receptors within central nervous system. Furthermore, recent years, a neurotrophic role for establishment balance circuits emerged. The precise way which exerts effects, site action,...
Exposure to short days (SD) induces profound changes in the physiology and behaviour of Siberian hamsters, including gonadal regression up 30% loss body weight. In a continuous SD environment after approximately 20 weeks, hamsters spontaneously revert long day (LD) phenotype, phenomenon referred as photorefractory response. Previously we have identified number genes that are regulated by photoperiod neuropil ventricular ependymal (VE) cells hypothalamus, although their importance...
Background: The thyroid hormone triiodothyronine (T3) is known to affect energy balance. Recent evidence points an action of T3 in the hypothalamus, a key area brain involved homeostasis, but components and mechanisms are far from understood. aim this study was identify hypothalamus that may be on balance regulatory mechanisms. Methods: Sprague Dawley rats were made hypothyroid by giving 0.025% methimazole (MMI) their drinking water for 22 days. On day 21, half MMI-treated received saline...
Hibernation is an energy-conserving behavior in winter characterized by two phases: torpor and arousal. During torpor, markedly reduced metabolic activity results inactivity decreased body temperature. Arousal periods intersperse the bouts feature increased metabolism euthermic Alterations physiological parameters, such as suppression of hemostasis, are thought to allow hibernators survive arousal without organ injury. While state potentially procoagulant, due low blood flow, viscosity,...
Abstract In nature Siberian hamsters utilize the decrement in day length following summer solstice to implement physiological adaptations anticipation of forthcoming winter, but also exploit an intrinsic interval timer initiate recrudescence winter solstice. However, information is lacking on temporal dynamics natural photoperiod photoperiodically regulated genes and their relationship adaptations. To address this, male born maintained outdoors were sampled every month over course one year....
Abstract Childhood obesity is a serious public health crisis and critical factor that determines future prevalence. Signals affecting adipocyte development in early postnatal life have strong potential to trigger childhood obesity; however, these signals are still poorly understood. We show here mitochondrial (mt)RNA efflux stimulates transcription of nuclear-encoded genes for mitobiogenesis thermogenesis adipocytes young mice human infants. While cytosolic mtRNA the interferon (IFN)...
In the Siberian hamster, seasonal weight loss occurs gradually over many weeks during autumn and winter. This is driven by a regulatory mechanism that able to integrate duration of exposure short days (SDs) with size body energy reserves. After food restriction in SDs, followed ad libitum refeeding, hamster does not return its former level; rather, it increases level defined length time spent SDs. this report, we show components thyroid hormone system are involved change expression response...
Siberian hamsters are seasonal mammals that survive a winter climate by making adaptations in physiology and behaviour. This includes gonadal atrophy, reduced food intake body weight. The underlying central mechanisms responsible for the physiological not fully established but involve reducing hypothalamic tri-iodthyronine (T3) levels. Juvenile born or raised short days (SD) respond similar manner, although with an inhibition of development growth instead reversing long day (LD) phenotype....
Abstract The objective of this study is to investigate the impact photoperiod on temporal and spatial expression genes involved in glucose metabolism brain seasonal mammal Phodopus sungorus (Siberian hamster). In situ hybridization was performed sections obtained from male hamsters held long (high body weight developed testes) or short (reduced with testicular regression). This analysis revealed upregulation glycogen localized tanycyte layer third ventricle. On basis these data a previously...
ABSTRACT Hibernation consists of periods low metabolism, called torpor, interspersed by euthermic arousal periods. During deep and daily (shallow) the number circulating leukocytes decreases, although cells, is restored to normal numbers upon arousal. Here, we show that neutropenia, during solely a result lowering body temperature, as reduction also occurred following forced hypothermia in summer hamsters rats do not hibernate. Splenectomy had no effect on neutrophils torpor. Margination...
Animals living at high or temperate latitudes are challenged by extensive changes in environmental conditions over seasons. Djungarian hamsters (Phodopus sungorus) able to cope with extremely cold ambient temperatures and food scarcity winter expressing spontaneous daily torpor. Daily torpor is a circadian controlled voluntary reduction of metabolism that can reduce energy expenditure up 65% when used frequently. In the past decades it has become more apparent, hypothalamus likely play key...
Djungarian hamsters are able to use spontaneous daily torpor (SDT) during the winter season as well fasting-induced (FIT) at any time of year cope with energetically challenging environmental conditions. Torpor is a state severely reduced metabolism pronounced decrease in body temperature, which enables animals their individual energy requirements. Despite sharing common characteristics, such mass before first expression and depressed temperature torpid state, FIT SDT differ several...
To survive the Siberian winter, Djungarian hamsters ( Phodopus sungorus ) adjust their behavior, morphology, and physiology to maintain energy balance. The reduction of body mass improvement fur insulation are followed by expression spontaneous daily torpor, a state reduced metabolism during resting phase save additional energy. Since these complex changes require time, upcoming winter is anticipated via decreasing photoperiod. Yet, extent adaptation torpor use highly individual. In this...
Torpor or heterothermy is an energy‐saving mechanism used by endotherms to overcome harsh environmental conditions. During winter, the garden dormouse ( Eliomys quercinus ) hibernates with multiday torpor bouts and body temperatures of a few degrees Celsius, interrupted brief euthermic phases. This study investigates gene expression within hypothalamus, key brain area controlling energy balance, adding information on differential potentially relevant orchestrate torpor. A de novo assembled...
Small mammals exhibit seasonal changes in intestinal morphology and function via increased intestine size resorptive surface and/or nutrient transport capacity to increase energy yield from food during winter. This study investigated whether or acute acclimation anticipated actual energetic challenges Djungarian hamsters also resulted higher resorption capacities owing small histology physiology. The show numerous energy-saving adjustments response short photoperiod. As spontaneous daily...
Abstract Vocalisations are increasingly being recognised as an important aspect of normal rodent behaviour yet little is known how they interact with other spontaneous behaviours such sleep and torpor, particularly in a social setting. We obtained chronic recordings the vocal adult male female Djungarian hamsters ( Phodopus sungorus ) housed under short photoperiod (8 h light, 16 dark, square wave transitions), different contexts. The animals were kept isolation or same-sex sibling pairs,...