Glosario de péptidos de investigación

Aliquot

An aliquot is a small, single-use portion divided from a larger reconstituted peptide solution and stored separately, typically frozen. Aliquoting limits each portion to a single freeze-thaw cycle, reducing cumulative degradation risk.

Alpha-Melanocyte-Stimulating Hormone (α-MSH)

Alpha-MSH is an endogenous 13-amino-acid peptide cleaved from the proopiomelanocortin (POMC) precursor that acts as the principal natural agonist of melanocortin receptors. It serves as the reference ligand against which synthetic melanocortin agonists are characterized in receptor-binding research.

Amino Acid

Amino acids are the building blocks of peptides and proteins. The specific sequence of amino acids determines a peptide’s structure and biological activity.

AMP-Activated Protein Kinase (AMPK)

AMPK is a cellular energy-sensing enzyme activated by a rising AMP-to-ATP ratio that regulates glucose uptake, fatty-acid oxidation, and mitochondrial biogenesis. It is a central signaling node studied in metabolic and mitochondrial-peptide research.

Bacteriostatic Water

Bacteriostatic water is USP-grade water containing 0.9% benzyl alcohol, used to reconstitute lyophilized compounds. The benzyl alcohol inhibits bacterial growth across multiple withdrawals.

Benzyl Alcohol

Benzyl alcohol is an aromatic alcohol used at 0.9% concentration as an antimicrobial preservative in bacteriostatic water. It inhibits bacterial growth in solution, which is what allows a single vial to be withdrawn from multiple times.

Brain-Derived Neurotrophic Factor (BDNF)

BDNF is a protein that supports neuron survival, growth, and synaptic plasticity. Neuropeptides such as Semax and Selank are studied for their effects on BDNF expression.

Certificate of Analysis (COA)

A Certificate of Analysis is a document issued by an analytical laboratory that reports the identity, purity, and quality of a specific product lot, including HPLC and mass-spectrometry results.

DPP-4

Dipeptidyl peptidase-4 (DPP-4) is a protease that inactivates native incretin hormones by cleaving their N-terminal dipeptide. Resistance to DPP-4 is a key design goal for incretin-mimetic research peptides.

Drug Affinity Complex (DAC)

A Drug Affinity Complex is a modification that binds a peptide to serum albumin to extend its half-life. CJC-1295 with DAC is studied for sustained GHRH-receptor activation.

Endotoxin

Endotoxins are bacterial-membrane components that can contaminate biological products. Endotoxin screening on a COA confirms a compound meets purity thresholds for research use.

Freeze-Thaw Cycling

Freeze-thaw cycling is the repeated freezing and thawing of a reconstituted peptide solution, which subjects the molecule to mechanical and thermal stress. Repeated cycling is a leading cause of peptide aggregation and loss of structural integrity during storage.

GIP Receptor

The GIP receptor (GIPR) is a class B G protein-coupled receptor for glucose-dependent insulinotropic polypeptide that signals through the Gs/cAMP pathway. It is the second canonical incretin receptor.

GLP-1 Receptor

The GLP-1 receptor (GLP-1R) is a class B G protein-coupled receptor that binds glucagon-like peptide-1 and signals through the Gs/cAMP pathway. It is a primary target of incretin-mimetic research peptides.

Glucagon Receptor

The glucagon receptor (GCGR) is a class B G protein-coupled receptor for the hormone glucagon that signals primarily through the Gs/cAMP pathway.

Growth Hormone Secretagogue

A growth hormone secretagogue is a compound that stimulates growth-hormone release by acting on the GH secretagogue receptor (GHSR-1a), distinct from GHRH-receptor agonists.

Growth Hormone Secretagogue Receptor (GHSR-1a)

GHSR-1a is the receptor targeted by GH secretagogues such as Ipamorelin. Selective agonists are studied for their ability to trigger GH release with minimal off-target hormone effects.

Growth Hormone-Releasing Hormone (GHRH)

GHRH is a hypothalamic hormone that stimulates the pituitary to release growth hormone. GHRH analogs such as CJC-1295 and Tesamorelin are studied for sustained activation of this pathway.

High-Performance Liquid Chromatography (HPLC)

HPLC is the gold-standard analytical method for determining peptide purity. It separates the components of a sample so the main peak’s area can be reported as a purity percentage.

IGF-1 Receptor (IGF-1R)

The IGF-1 receptor is a transmembrane receptor tyrosine kinase that binds IGF-1 (and insulin, with lower affinity) to trigger PI3K/Akt and Ras/MAPK signaling cascades. It is a standard target in cell-proliferation and receptor-binding research.

Incretin

Incretins are gut-derived hormones — principally GIP and GLP-1 — that potentiate glucose-dependent insulin signaling. Synthetic incretin-receptor agonists are studied in vitro for receptor binding and downstream cAMP signaling.

Insulin-like Growth Factor 1 (IGF-1)

IGF-1 is a peptide hormone structurally homologous to insulin that mediates many of growth hormone’s downstream cellular effects. It is produced primarily by the liver following GH-receptor activation and signals through the IGF-1 receptor.

Lyophilization

Lyophilization is a freeze-drying process that removes water from a peptide, leaving a stable dry powder that resists hydrolysis and degradation during storage.

Mass Spectrometry

Mass spectrometry confirms a peptide’s molecular weight, verifying its amino-acid sequence identity by measuring the mass-to-charge ratio of ionized molecules.

Melanocortin Receptor

Melanocortin receptors (MC1R–MC5R) are a family of receptors involved in pigmentation and neuroendocrine signaling. Agonists such as PT-141 and MT-2 are studied for receptor binding and downstream signaling.

Molecular Weight

Molecular weight is the mass of a peptide molecule, confirmed by mass spectrometry. The observed mass should match the theoretical mass within a narrow margin to verify sequence identity.

Peptide

A peptide is a short chain of amino acids linked by peptide bonds, generally defined as containing between two and fifty residues — shorter than a full-length protein.

Peptide Aggregation

Aggregation is the clumping of peptide molecules, often caused by improper storage or freeze-thaw cycling. It can reduce solubility and compromise research results.

PT-141

PT-141 is a synthetic cyclic heptapeptide analog of alpha-MSH that acts as a nonselective melanocortin-receptor agonist, with highest affinity at MC4R. It is studied in preclinical research for melanocortin-receptor binding and downstream signaling.

Purity

Purity is the percentage of a sample that is the target compound, determined by HPLC. Research-grade peptides are typically verified at ≥99% purity on a lot-specific COA.

Reconstitution

Reconstitution is the process of dissolving a lyophilized peptide in a solvent such as bacteriostatic water to prepare it for laboratory use.

Research Use Only (RUO)

Research Use Only designates a product intended exclusively for in-vitro and laboratory research. RUO compounds are not drugs and are not intended for human or animal use.

Sirtuin

Sirtuins are a family of NAD+-dependent deacetylase enzymes (SIRT1–SIRT7) that regulate cellular metabolism, DNA repair, and stress response. Their catalytic activity depends directly on cellular NAD+ availability.

Solid-Phase Peptide Synthesis (SPPS)

SPPS is the standard method for producing research peptides, building the chain one amino acid at a time on an insoluble resin through repeating deprotection and coupling cycles.

Thymosin Beta-4 (Tβ4)

Thymosin beta-4 is a 43-amino-acid endogenous regulatory peptide that binds and sequesters monomeric G-actin, influencing cytoskeletal dynamics and cell migration. TB-500 is a synthetic fragment derived from its actin-binding domain, studied in preclinical models for the same mechanistic pathway.