Cinnamoylglycine is a glycine conjugate of cinnamic acid and a urinary metabolite in humans. It is used as a potential urinary biomarker.

Tuftsin diacetate, a tetrapeptide, is a macrophage/microglial activator. Tuftsin is a tetrapeptide, Thr-Lys-Pro-Arg, which resides in the Fc-domain of the heavy chain of immunoglobulin G. Tuftsin possesses a broad spectrum of activities related primarily to the immune system function and exerts on phagocytic cells, notably on macrophages.

Endogenous peptide activator of intestinal guanylyl cyclase; secreted mainly by the gastrointestinal mucosa. Regulates water and electrolyte transport in intestinal and renal epithelia.