Energy Expenditure
Definition
Total energy used over a day, made up of resting metabolism, the thermic effect of food and physical activity. Glucagon-receptor activity is one of the few peptide mechanisms proposed in trials to raise it directly rather than by reducing intake.
Terms used in this definition
Other entries this definition refers to.
What this means for research sourcing
Mechanistic terms like this describe how research compounds behave in vitro. See the mechanism overviews for compounds Volta stocks.
Related Terms in Pharmacology
Insulin Resistance
A state in which muscle, liver and fat respond poorly to insulin, so more of it is needed to keep glucose in range. It is the physiological backdrop to most metabolic endpoints reported in this field.
Insulin Sensitivity
The converse measure: how strongly tissues respond to a given amount of insulin. Clamp studies are the reference method and surrogate indices derived from fasting bloods are what most papers actually report.
Angiogenesis
The growth of new blood vessels from vessels that already exist. It is central to tissue repair and is the mechanism most often proposed for the healing peptides, almost entirely on the strength of animal models.
Nitric Oxide
A short-lived gaseous signalling molecule that relaxes vascular smooth muscle and widens vessels. It is a separate pathway from melanocortin signalling, a distinction that gets blurred in writing about peptides with vascular effects.
Prostaglandin
A family of locally acting lipid mediators derived from arachidonic acid, involved in inflammation, pain, smooth-muscle tone and blood flow. They are lipids rather than peptides and appear here because peptide studies measure them as readouts.
Myostatin
A protein secreted by muscle that acts as a brake on its own growth, also called GDF-8. Blocking it increases muscle mass in rodent models, which is why follistatin and ACE-031 have been studied, and why the clinical record for the approach is a run of failures.
Activin Type IIB Receptor (ActRIIB)
The receptor through which myostatin and related TGF-beta ligands signal to limit skeletal muscle mass. Decoy receptors and antibodies aimed at it are the main pharmacological route to inhibiting that signal.
Senolytic
A compound meant to clear senescent cells selectively while leaving dividing ones alone. FOXO4-DRI is the peptide studied this way, in cell and animal models, and human data for the approach is minimal.