Scientific Glossary

A compound that binds to a receptor and activates it, producing a biological response. A full agonist produces the maximum possible response at that receptor. A partial agonist binds the same receptor but produces a submaximal effect even at saturating concentrations.

The monomer unit of proteins and peptides. Each amino acid has an amine group, a carboxyl group and a distinctive side chain. Twenty canonical amino acids are encoded by the genetic code; peptide sequence determines structure and biological activity.

A cellular energy sensor activated when AMP:ATP ratio rises (low energy state). AMPK promotes catabolic pathways (fatty acid oxidation, glucose uptake) and inhibits anabolic processes. MOTS-c is studied for its ability to activate AMPK in skeletal muscle and adipose tissue.

The formation of new blood vessels from pre-existing vasculature. Key regulatory factors include VEGF and FGF. BPC-157 and GHK-Cu are studied for their purported pro-angiogenic effects in preclinical wound-healing models.

A compound that binds to a receptor without activating it, thereby blocking the action of endogenous ligands or exogenous agonists. Antagonists have no intrinsic activity but reduce the response to agonists.

Sterile water containing 0.9% benzyl alcohol as a preservative. Used as a solvent for reconstituting lyophilised peptides in laboratory research. The benzyl alcohol preservative inhibits bacterial growth, extending multi-use stability of the reconstituted solution.

A neurotrophin that supports the growth, survival and differentiation of neurons. BDNF signalling via TrkB receptors is implicated in learning, memory and mood regulation. Selank and Semax are investigated for effects on BDNF mRNA and protein expression in animal models.

The fraction of an administered dose that reaches systemic circulation in unchanged, active form. Intravenous administration is defined as 100% bioavailable. Subcutaneous and intranasal peptide routes typically show lower bioavailability due to first-pass effects and enzymatic degradation.

A unique numerical identifier assigned by the Chemical Abstracts Service to every chemical substance. CAS numbers provide an unambiguous way to identify a compound regardless of naming conventions. Useful for verifying compound identity across databases and regulatory submissions.

The volume of plasma from which a compound is completely removed per unit time. Peptides are frequently cleared by renal filtration, proteolytic degradation or hepatic metabolism. DAC technology and PEGylation are engineering approaches used to slow clearance and extend half-life.

A document issued by an analytical laboratory confirming the identity and purity of a batch of compound. For peptides, a COA typically includes HPLC purity data, LC-MS identity confirmation, and batch/lot number. Uptide publishes COAs via the Janoshik analytical laboratory.

A reduction in receptor responsiveness following repeated or prolonged exposure to a ligand. Mechanisms include receptor internalisation, phosphorylation and downregulation of receptor expression. Clinically relevant for growth hormone secretagogues, where pulsatile administration is thought to reduce desensitisation compared to continuous infusion.

The effective concentration producing 50% of the maximum response. A lower EC50 indicates higher potency — the compound is active at smaller amounts. EC50 is derived from dose–response curves in in vitro or in vivo experiments.

A pituitary peptide hormone (191 amino acids) with anabolic, lipolytic and immunomodulatory effects. Secretion is pulsatile and regulated by GHRH (stimulatory) and somatostatin (inhibitory). Research interest centres on age-related decline in GH secretion (somatopause) and the pharmacological restoration of pulsatility.

The hypothalamic peptide that stimulates pituitary somatotrophs to secrete growth hormone. Synthetic GHRH analogues (CJC-1295, sermorelin, tesamorelin) are studied for their ability to augment endogenous GH pulsatility without suppressing the GH axis.

An incretin hormone secreted by intestinal L-cells in response to nutrient ingestion. GLP-1 stimulates glucose-dependent insulin secretion, suppresses glucagon, delays gastric emptying and activates CNS satiety circuits. GLP-1 receptor agonists (semaglutide, retatrutide) are approved for type 2 diabetes and obesity.

The time required for the plasma concentration of a compound to fall to half its initial value. A longer half-life generally means less frequent administration is needed to maintain steady-state exposure. Values reported for research peptides are usually derived from animal pharmacokinetic models unless specified.

Drug Affinity Complex (DAC) technology appends a lysine-maleimide group to a peptide, enabling covalent binding to circulating albumin. This dramatically extends plasma half-life. CJC-1295 with DAC has an estimated half-life of 6–8 days versus ~30 min for the equivalent peptide without DAC.

An analytical technique used to separate, identify and quantify components in a mixture. In peptide quality control, HPLC measures purity (typically reported as area percentage). A purity of ≥98% by HPLC is considered research grade. Uptide uses Janoshik Analytical for HPLC verification.

A peptide hormone produced primarily by the liver in response to growth hormone stimulation. IGF-1 mediates many of GH's anabolic effects, including muscle and bone growth. Compounds targeting the GH/IGF-1 axis (CJC-1295, sermorelin, tesamorelin, ipamorelin) act upstream to increase endogenous IGF-1.

Experiments conducted in a controlled laboratory environment outside of a living organism — e.g. in cell cultures or isolated tissue. In vitro findings often do not directly translate to in vivo biology due to differences in metabolism, distribution and cellular context.

Research conducted within a living organism. In the context of preclinical peptide research, this typically means rodent (rat or mouse) models. In vivo studies provide more physiologically relevant data than in vitro experiments but still face significant challenges in translating to human outcomes.

A gastrointestinal hormone that stimulates insulin secretion in a glucose-dependent manner after food intake. The major incretins are GLP-1 and GIP (glucose-dependent insulinotropic polypeptide). Incretin-based therapies (GLP-1 receptor agonists, DPP-4 inhibitors) are central to modern metabolic pharmacology.

A hyphenated analytical technique combining the separation capability of HPLC with the mass measurement of mass spectrometry. LC-MS is used to confirm the molecular identity of a peptide by matching measured m/z (mass-to-charge) values against the theoretical mass of the compound.

Any molecule that binds to a specific receptor or protein. In peptide research, both synthetic peptides and endogenous hormones are ligands. Binding affinity (Kd) describes how tightly a ligand binds its target.

Freeze-drying process used to preserve peptide stability. Most research peptides are supplied as a lyophilised (freeze-dried) powder that is reconstituted with bacteriostatic water or sterile saline before use. The process removes moisture, extending shelf life.

The sum of the atomic masses of all atoms in a molecule, expressed in daltons (Da) or g/mol. Peptide MW is determined by its amino acid sequence. MW is used in reconstitution calculations and is a key parameter in LC-MS identity confirmation.

An essential coenzyme involved in cellular energy metabolism and redox reactions. NAD+ is a substrate for sirtuins (SIRT1–SIRT7) and PARP enzymes, linking it to DNA repair, mitochondrial biogenesis and ageing biology. NAD+ levels decline with age; precursor supplementation (NMN, NR) is studied for metabolic restoration.

A short chain of amino acids linked by peptide bonds. Peptides are distinguished from proteins by length — conventionally fewer than ~50 amino acids. They serve as hormones, neurotransmitters, signalling molecules and structural components. Synthetic peptides in research replicate or modify naturally occurring sequences.

Research conducted in cell cultures (in vitro) or animal models (in vivo) before any human testing. Preclinical data is necessary but not sufficient to predict human outcomes. Most peptides in this catalogue have preclinical but not clinical evidence; this represents a meaningful evidence gap.

The gold standard for clinical evidence. Participants are randomly assigned to intervention or placebo groups, enabling unbiased estimation of treatment effect. Absence of RCT data for a compound does not mean it is ineffective — it means human evidence is insufficient to draw conclusions.

A cell-surface or intracellular protein that specifically binds a ligand (e.g. a peptide) and transduces a signal into the cell. Examples relevant to this catalogue: GHS-R1a (growth hormone secretagogue receptor), GLP-1R, MC1R–MC5R (melanocortin receptors).

The process of dissolving a lyophilised peptide powder in a sterile solvent (typically bacteriostatic water) to produce a solution of known concentration. Concentration is calculated as: mg peptide ÷ mL solvent = mg/mL.

A substance that causes another substance to be secreted. Growth hormone secretagogues (GHS) — such as ipamorelin, GHRP-2 and GHRP-6 — stimulate pituitary somatotrophs to release GH. They act via GHS-R1a (the ghrelin receptor), distinct from the GHRH receptor.

The degree to which a compound produces effects at one receptor or target relative to others. High selectivity reduces off-target effects. Ipamorelin is often cited as selective for GHS-R1a with minimal cortisol or prolactin release compared to earlier secretagogues like GHRP-6.

A family of NAD+-dependent deacylase enzymes (SIRT1–SIRT7) involved in gene expression regulation, DNA repair, metabolic homeostasis and ageing. Sirtuins are downstream effectors in the mitochondrial signalling pathway studied in the context of longevity research.

A signalling protein that stimulates angiogenesis. Elevated in wound sites and tumours. Several compounds in this catalogue — including BPC-157, TB-500 and GHK-Cu — are studied in relation to VEGF pathway modulation in preclinical models.

A theoretical volume that relates total drug in the body to plasma concentration. A high Vd suggests the compound distributes extensively into tissue rather than remaining in the bloodstream.