Faculty Opinions recommendation of Cellular energy depletion resets whole-body energy by promoting coactivator-mediated dietary fuel absorption.

The hypothalamic regulation of appetite governs whole-body energy balance. Satiety is regulated by endocrine factors including leptin, and impaired leptin signaling is associated with obesity. Despite the anorectic effect of leptin through the regulation of the hypothalamic feeding circuit, a distinct downstream mediator of leptin signaling in neuron remains unclear. Angiopoietin-like growth factor (AGF) is a peripheral activator of energy expenditure and antagonizes obesity. However, the regulation of AGF expression in brain and localization to mediate anorectic signaling is unknown. Here, we demonstrated that AGF is expressed in proopiomelanocortin (POMC)-expressing neurons located in the arcuate nucleus (ARC) of the hypothalamus. Unlike other brain regions, hypothalamic AGF expression is stimulated by leptin-induced signal transducers and activators of transcription 3 (STAT3) phosphorylation. In addition, leptin treatment to hypothalamic N1 cells significantly enhanced the promoter activity of AGF. This induction was abolished by the pretreatment of ruxolitinib, a leptin signaling inhibitor. These results indicate that hypothalamic AGF expression is induced by leptin and colocalized to POMC neurons.

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Targeting Mitochondria in Diabetes

International Journal of Molecular Sciences ◽

10.3390/ijms22126642 ◽

2021 ◽

Vol 22 (12) ◽

pp. 6642

Author(s):

Nina Krako Jakovljevic ◽

Kasja Pavlovic ◽

Aleksandra Jotic ◽

Katarina Lalic ◽

Milica Stoiljkovic ◽

...

Keyword(s):

Insulin Resistance ◽

Mitochondrial Function ◽

Whole Body ◽

Noncommunicable Diseases ◽

Pharmacological Interventions ◽

Cellular Energy ◽

Cellular Energy Metabolism ◽

Data Comparison ◽

Selection Of

Type 2 diabetes (T2D), one of the most prevalent noncommunicable diseases, is often preceded by insulin resistance (IR), which underlies the inability of tissues to respond to insulin and leads to disturbed metabolic homeostasis. Mitochondria, as a central player in the cellular energy metabolism, are involved in the mechanisms of IR and T2D. Mitochondrial function is affected by insulin resistance in different tissues, among which skeletal muscle and liver have the highest impact on whole-body glucose homeostasis. This review focuses on human studies that assess mitochondrial function in liver, muscle and blood cells in the context of T2D. Furthermore, different interventions targeting mitochondria in IR and T2D are listed, with a selection of studies using respirometry as a measure of mitochondrial function, for better data comparison. Altogether, mitochondrial respiratory capacity appears to be a metabolic indicator since it decreases as the disease progresses but increases after lifestyle (exercise) and pharmacological interventions, together with the improvement in metabolic health. Finally, novel therapeutics developed to target mitochondria have potential for a more integrative therapeutic approach, treating both causative and secondary defects of diabetes.

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Exercise and MEF2–HDAC interactions

Applied Physiology Nutrition and Metabolism ◽

10.1139/h07-082 ◽

2007 ◽

Vol 32 (5) ◽

pp. 852-856 ◽

Cited By ~ 21

Author(s):

Sean L. McGee

Keyword(s):

Skeletal Muscle ◽

Protein Kinase ◽

Nuclear Export ◽

Energy Homeostasis ◽

Whole Body ◽

Positive Health ◽

Exercise Induced ◽

Amp Activated Protein Kinase ◽

Body Energy ◽

Skeletal Muscle Adaptations

Exercise increases the metabolic capacity of skeletal muscle, which improves whole-body energy homeostasis and contributes to the positive health benefits of exercise. This is, in part, mediated by increases in the expression of a number of metabolic enzymes, regulated largely at the level of transcription. At a molecular level, many of these genes are regulated by the class II histone deacetylase (HDAC) family of transcriptional repressors, in particular HDAC5, through their interaction with myocyte enhancer factor 2 transcription factors. HDAC5 kinases, including 5′-AMP-activated protein kinase and protein kinase D, appear to regulate skeletal muscle metabolic gene transcription by inactivating HDAC5 and inducing HDAC5 nuclear export. These mechanisms appear to participate in exercise-induced gene expression and could be important for skeletal muscle adaptations to exercise.

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The Role of AMPK Signaling in Brown Adipose Tissue Activation

Cells ◽

10.3390/cells10051122 ◽

2021 ◽

Vol 10 (5) ◽

pp. 1122

Author(s):

Jamie I. van der van der Vaart ◽

Mariëtte R. Boon ◽

Riekelt H. Houtkooper

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

Whole Body ◽

Ampk Signaling ◽

Mitochondrial Homeostasis ◽

Brown Adipose ◽

Metabolic Stresses ◽

Amp Activated Protein Kinase ◽

Body Energy

Obesity is becoming a pandemic, and its prevalence is still increasing. Considering that obesity increases the risk of developing cardiometabolic diseases, research efforts are focusing on new ways to combat obesity. Brown adipose tissue (BAT) has emerged as a possible target to achieve this for its functional role in energy expenditure by means of increasing thermogenesis. An important metabolic sensor and regulator of whole-body energy balance is AMP-activated protein kinase (AMPK), and its role in energy metabolism is evident. This review highlights the mechanisms of BAT activation and investigates how AMPK can be used as a target for BAT activation. We review compounds and other factors that are able to activate AMPK and further discuss the therapeutic use of AMPK in BAT activation. Extensive research shows that AMPK can be activated by a number of different kinases, such as LKB1, CaMKK, but also small molecules, hormones, and metabolic stresses. AMPK is able to activate BAT by inducing adipogenesis, maintaining mitochondrial homeostasis and inducing browning in white adipose tissue. We conclude that, despite encouraging results, many uncertainties should be clarified before AMPK can be posed as a target for anti-obesity treatment via BAT activation.

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Role of AMPK in mammals reproduction: Specific controls and whole-body energy sensing

Comptes Rendus Biologies ◽

10.1016/j.crvi.2018.10.003 ◽

2019 ◽

Vol 342 (1-2) ◽

pp. 1-6 ◽

Cited By ~ 3

Author(s):

Thi Mong Diep Nguyen

Keyword(s):

Whole Body ◽

Energy Sensing ◽

Body Energy

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Energy Metabolism of Bone

Toxicologic Pathology ◽

10.1177/0192623317737065 ◽

2017 ◽

Vol 45 (7) ◽

pp. 887-893 ◽

Cited By ~ 10

Author(s):

Katherine J. Motyl ◽

Anyonya R. Guntur ◽

Adriana Lelis Carvalho ◽

Clifford J. Rosen

Keyword(s):

Bone Remodeling ◽

Energy Homeostasis ◽

Bone Structure ◽

Bone Cells ◽

Bone Cell ◽

Whole Body ◽

Blood Calcium ◽

Micro Cracks ◽

Intimate Link ◽

Body Energy

Biological processes utilize energy and therefore must be prioritized based on fuel availability. Bone is no exception to this, and the benefit of remodeling when necessary outweighs the energy costs. Bone remodeling is important for maintaining blood calcium homeostasis, repairing micro cracks and fractures, and modifying bone structure so that it is better suited to withstand loading demands. Osteoclasts, osteoblasts, and osteocytes are the primary cells responsible for bone remodeling, although bone marrow adipocytes and other cells may also play an indirect role. There is a renewed interest in bone cell energetics because of the potential for these processes to be targeted for osteoporosis therapies. In contrast, due to the intimate link between bone and energy homeostasis, pharmaceuticals that treat metabolic disease or have metabolic side effects often have deleterious bone consequences. In this brief review, we will introduce osteoporosis, discuss how bone cells utilize energy to function, evidence for bone regulating whole body energy homeostasis, and some of the unanswered questions and opportunities for further research in the field.

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