Bioactive molecules

Bioactive molecules are compounds — peptides, small molecules, proteins, or biologics — that produce a measurable physiological effect on a living organism. The effect may be agonism or antagonism at a receptor, modulation of enzymatic activity, alteration of gene expression, or direct interaction with cellular structures.

The compounds catalogued on Retapedia are bioactive by definition: each is reported to act on a molecular target, such as a receptor, an enzyme, or a structural protein, and to produce a downstream response. Their use as therapeutic agents or as performance enhancers follows directly from that activity.

Peptide bioactivity

Short peptide sequences can be remarkably potent. Endogenous regulatory peptides such as GLP-1, ghrelin, and the GH-axis secretagogues act at very low concentrations (active GLP-1 circulates at picomolar levels) and are subject to tight feedback regulation. Synthetic analogues are engineered to retain receptor binding while improving stability against proteolytic degradation — extending plasma half-life from minutes to about a week.

Catalogued bioactive peptides

Retapedia entries cover bioactive peptides spanning the GH/IGF-1 axis, incretin pathway (GLP-1 receptor agonists), tissue repair (BPC-157, TB-500), neuroactive peptides (Semax, Selank), and metabolic regulation (the coenzyme NAD+, a small molecule rather than a peptide). See the peptide category for the full list.