Glossary Terms

Proteins the heart releases when it’s under stress — used as blood tests to diagnose heart failure and track disease

The protective filter around the retina, similar to the blood-brain barrier, that prevents most drugs from reaching the back of

A highly selective filter between your bloodstream and your brain that keeps most drugs — and most peptides — out

A measurable signal in your blood, tissue, or elsewhere that tells you something is happening biologically — a proxy for

The fraction of a dose that actually reaches your bloodstream in active form — the rest is lost to degradation

A flat, extended structural shape that some peptides and proteins fold into — associated with both stability and, in some

The sterile water most research peptides get dissolved in before injection — it contains a small amount of preservative that

When a cell releases a signaling molecule that acts back on itself.Contrast with paracrine (acts on neighboring cells in the

Programmed cell death — the body’s controlled process for eliminating cells that are damaged, old, or no longer needed.Distinct from

A large immune protein that recognizes and binds to a specific target with high precision — the basis for most