Research chemicals known as peptides, many of them banned by the World Anti Doping Agency and some not approved for human use in the United States, are available with the simple click of Cortisol Negative Feedback Loop Mechanism How GHK Peptide Works Signaling GHK acts as a switch for skin repair: Interacts with adenosine receptors reduces inflammation Activates MAPK ERK, PI3K Akt, TGF pathways Stimulates fibroblasts & keratinocytes boosts collagen, elastin The Effect of the Human Peptide GHK on Gene Expression Relevant to Nervous System Function and Cognitive Decline The Physiological Role of Ghrelin in the Regulation of Energy and Glucose Homeostasis Cureus