The melanocortin system is an ancient modulatory system comprising a family of 5 melanocortin receptors and a set of naturally occurring melanocortin peptides that bind to and activate these receptors. The melanocortin receptors (MC1R-MC5R) are located on many cell types and are spread throughout most body systems.
MC1R and MC3R are believed to be the key receptors involved in direct effects on the immune system and these receptors are located on immune cells and associated structural and supportive cells. When activated, MC1R and MC3R provide both direct anti-inflammatory effects, such as causing immune cells to produce fewer pro-inflammatory molecules and stimulating pro-resolution effects such as switching cells to perform inflammation ‘cleanup’ or regulatory functions.
MC4R is primary expressed in the central nervous system and plays a pivotal role in central regulation of metabolism including food intake. MC5R are found in exocrine glands, expressed by some subtypes of immune active cells in the eye among others.
MC2R is primary expressed in the adrenal glands where stimulation is directly associated to release of cortisol, a steroid. SynAct’s selective melanocortin agonists do not activate MC2R and do not cause the release of cortisol from the adrenal glands.