Public resource
Peptide Science Glossary
Plain-language definitions of key terms in peptide biology, receptor signaling, metabolic science, research design and regulatory status.
- Amino acid
- The building block of peptides and proteins. Twenty standard amino acids are linked in sequence by peptide bonds.
- Peptide
- A short chain of amino acids, usually fewer than about 50. Many hormones and signaling molecules are peptides.
- Receptor
- A protein, often on the cell surface, that binds a specific signaling molecule and triggers a response inside the cell.
- Agonist
- A molecule that binds a receptor and activates it.
- Antagonist
- A molecule that binds a receptor and blocks its activation.
- Half-life
- The time needed for the concentration of a substance in the body to fall by half.
- Incretin
- Gut-derived hormones, such as GLP-1 and GIP, released after eating that influence insulin secretion and appetite signaling.
- GLP-1
- Glucagon-like peptide-1, an incretin hormone. Some approved medications act on its receptor.
- Angiogenesis
- The formation of new blood vessels from existing ones.
- Extracellular matrix
- The network of proteins, such as collagen, that structurally supports tissues outside cells.
- Preclinical research
- Studies in cells or animals. Results may not translate to humans.
- Randomized controlled trial
- A human study in which participants are randomly assigned to groups, reducing bias when comparing interventions.
- Systematic review
- A structured summary of all available studies on a question, sometimes combined statistically in a meta-analysis.
- Endpoint
- The outcome a study measures to judge whether an intervention had an effect.
- Investigational
- A compound under formal clinical evaluation that has not been approved for the use being studied.
- Off-label
- Use of an approved medication outside its approved indication, dose or population.
- Regulatory approval
- Authorization from an agency such as the FDA for a defined use, based on submitted evidence of safety and efficacy.
- Safety signal
- Information suggesting a possible new risk associated with a substance, which requires further investigation.
These terms are explained in context, with diagrams, inside Peptide Essentials.
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