Triiodothyronine (T3) is an active hormone synthesized in the thyroid. Thyroid is crucial for various physiological processes. Iodine inclusion is the main peculiarity of thyroid hormones. This feature plays a significant value in body development and metabolism. Specifically, T3 is engaged in the regulation of metabolism and energy allocation. Due to this feature, it influences almost all tissues in the body. The hormone is essential for the normal development of the central nervous system during growth. It also contributes to the maintenance of metabolic homeostasis in adults.
The thyroid gland stores large quantities of hormones. They can be produced in different body organs, including the liver, the brain, etc. The adenohypophysis regulates the amount of thyroid hormones in plasma. It uses Thyroid-Stimulating Hormone (TSH) and acts through negative feedback mechanisms. T4 (thyroxine) is the primary hormone produced by the thyroid gland. It is used to produce T3 by converting it into peripheral tissues.
Effects
Regulates metabolism.
Enhances fat burning.
Promotes muscle growth when combined with anabolic steroids.
Mechanism of Action
The action of Liothyronine (T3) in the body imitates the activity of natural thyroid hormones, primarily Triiodothyronine. It regulates diverse metabolic processes. The ingredient affects the body on the molecular level, acting through biochemical reactions. Most frequently, the substance binds to thyroid hormone receptors (THRs) located in the nuclei of cells. Below, we explain through which mechanisms the component affects metabolism:
Increase in basal metabolic rate (BMR). T3 stimulates the production of ATP and increases the rate of oxygen consumption by cells. These effects result in enhanced energy expenditure.
Promotion of lipolysis. T3 influences triglycerides, stimulating their breakdown into free fatty acids and glycerol. This impact makes fat stores more accessible for energy production.
Thermogenesis. T3 affects the process of heat production in the body. The substance influences brown adipose tissue, which contributes to higher energy expenditure.
Enhanced oxidative phosphorylation. The presence of T3 in the body leads to an increase in the number of mitochondria in cells. This fact boosts the rate of an oxidative process of transferring a phosphoric acid residue from a phosphorylating donor agent to a substrate.
Thyroid Hormone Receptor Binding
When entering the body, T3 strives to penetrate cell nuclei and bind to thyroid hormone receptors (THRs). In the body, these receptors perform the function of transcription factors, regulating specific gene expression. When the binding between T3 and the receptor-hormone complex occurs, the latter can further bind to thyroid hormone response e
