Peptides are tiny protein messengers that help cells talk by binding to...

https://web-wiki.win/index.php/Why_Lab_Findings_Are_Not_Clinical_Conclusions_for_Peptides

Peptides are tiny protein messengers that help cells talk by binding to specific receptors. Researchers use peptides to study how receptors work, test which peptides bind best (selectivity), and observe the chain of signals triggered inside cells