The gray mouse lemur Microcebus murinus is a rare example of a primate exhibiting daily torpor. In captive animals, we examined the metabolic rate during arousal from torpor and showed that this process involved nonshivering thermogenesis (NST). Under thermoneutrality (28 degrees C), warming-up from daily torpor (body temperature <33 degrees C) involved a rapid (<5 min) increase of O(2) consumption that was proportional to the depth of torpor (n = 8). The injection of a beta-adrenergic agonist (isoproterenol) known to elicit NST induced a dose-dependent increase in metabolic rate (n = 8). Moreover, maximum thermogenesis was increased by cold exposure. For the first time in this species, anatomic and histological examination using an antibody against uncoupling protein (UCP) specifically demonstrated the presence of brown fat. With the use of Western blotting with the same antibody, we showed a likely increase in UCP expression after cold exposure, suggesting that NST is also used to survive low ambient temperatures in this tropical species.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1152/ajpregu.00525.2002 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
The secretory function of adipose tissues in metabolic regulation.
Life Metab
April 2024
Key Laboratory of Metabolism and Molecular Medicine of the Ministry of Education, Department of Biochemistry and Molecular Biology of School of Basic Medical Sciences and Department of Endocrinology and Metabolism of Zhongshan Hospital, Fudan University, Shanghai 200032, China.
In addition to their pivotal roles in energy storage and expenditure, adipose tissues play a crucial part in the secretion of bioactive molecules, including peptides, lipids, metabolites, and extracellular vesicles, in response to physiological stimulation and metabolic stress. These secretory factors, through autocrine and paracrine mechanisms, regulate various processes within adipose tissues. These processes include adipogenesis, glucose and lipid metabolism, inflammation, and adaptive thermogenesis, all of which are essential for the maintenance of the balance and functionality of the adipose tissue micro-environment.
View Article and Find Full Text PDFSympathetic innervation of interscapular brown adipose tissue is not a predominant mediator of Oxytocin (OT)-elicited reductions of body weight gain and adiposity in male diet-induced obese rats.
Front Drug Deliv
December 2024
VA Puget Sound Health Care System, Office of Research and Development Medical Research Service, Department of Veterans Affairs Medical Center, Seattle, WA 98108, USA.
Recent studies indicate that central administration of oxytocin (OT) reduces body weight (BW) in high fat diet-induced obese (DIO) rodents by reducing energy intake and increasing energy expenditure (EE). Previous studies in our lab have shown that administration of OT into the fourth ventricle (4V; hindbrain) elicits weight loss and stimulates interscapular brown adipose tissue temperature (T) in DIO rats. We hypothesized that OT-elicited stimulation of sympathetic nervous system (SNS) activation of IBAT contributes to its ability to activate BAT and reduce BW in DIO rats.
View Article and Find Full Text PDFTroponins and Skeletal Muscle Pathologies.
Biochemistry (Mosc)
December 2024
Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia.
Skeletal muscles account for ~30-40% of the total weight of human body and are responsible for its most important functions, including movement, respiration, thermogenesis, and glucose and protein metabolism. Skeletal muscle damage negatively impacts the whole-body functioning, leading to deterioration of the quality of life and, in severe cases, death. Therefore, timely diagnosis and therapy for skeletal muscle dysfunction are important goals of modern medicine.
View Article and Find Full Text PDFHypothalamic neural circuits regulating energy expenditure.
Vitam Horm
January 2025
Lilly Diabetes Research Center, Indiana Biosciences Research Institute, Indianapolis, IN, United States; Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States. Electronic address:
The hypothalamus plays a central role in regulating energy expenditure and maintaining energy homeostasis, crucial for an organism's survival. Located in the ventral diencephalon, it is a dynamic and adaptable brain region capable of rapid responses to environmental changes, exhibiting high anatomical and cellular plasticity and integrates a myriad of sensory information, internal physiological cues, and humoral factors to accurately interpret the nutritional state and adjust food intake, thermogenesis, and energy homeostasis. Key hypothalamic nuclei contain distinct neuron populations that respond to hormonal, nutrient, and neural inputs and communicate extensively with peripheral organs like the gastrointestinal tract, liver, pancreas, and adipose tissues to regulate energy production, storage, mobilization, and utilization.
View Article and Find Full Text PDFEffect of different cold acclimation methods on the exercise capacity of mice in low-temperature environments.
J Therm Biol
January 2025
China Institute of Sport Science, Beijing, 100061, China. Electronic address:
Objective: This study aimed to evaluate the effects of different cold acclimation strategies on exercise performance in male mice exposed to low-temperature environments.
Methods: Male mice were subjected to five distinct acclimation regimens over 8 weeks: immersion at 10 °C (10 °CI) or 20 °C (20 °CI), swimming at 10 °C (10 °CS), 20 °C (20 °CS), or 34 °C (34 °CS). During the first 2 weeks, the acclimation time progressively decreased from 30 min to 3 min per day, and the water temperatures were lowered from 34 °C to the target levels, followed by 6 weeks of consistent exposure.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!