Somatostatin-25: lab peptide that curbs growth hormone
A 25-amino-acid peptide first found in sheep brain tissue that acts like somatostatin, a natural hormone which dials down growth hormone release; used only as a laboratory research tool, not a medicine.
- Class
- Somatostatin-related peptide fragment
- Status
- No approved therapeutic status; research peptide only
- Best-supported effect
- Somatostatin-like bioactivity and immunoreactivity in in vitro assay systems
- Main caveat
- Evidence is limited to in vitro bioassay data; no animal efficacy or human trial data are attached to this card
A researcher, an agent, or an algorithm wrote down the sequence and picked a target to hit.
An AI model like OpenFold3 or AlphaFold built a 3D structure and scored how well it fits the binding site.
A second contributor repeated the computation on their own hardware and the scores matched.
A chemistry service or a researcher ordered the sequence, it was manufactured, and mass spectrometry confirmed the right molecule was produced.
A binding or activity measurement confirmed that it actually does what the computer predicted — or didn't.
Snapshot
Class: Somatostatin-related peptide fragment
Evidence tier: In vitro / assay evidence
Status: No approved therapeutic status identified; research peptide only
Best-supported effect: Somatostatin-like bioactivity and immunoreactivity in in vitro assay systems
Main caveat: Evidence is limited to in vitro bioassay data; no animal efficacy or human trial data are identified
What this is
Somatostatin-25 peptide is a 25-amino-acid peptide isolated from ovine (sheep) hypothalamus that displays somatostatin-like immunoreactivity and in vitro biological activity. It is a naturally derived fragment or derivative of the somatostatin peptide family, identified through its cross-reactivity in somatostatin immunoassays and its activity in an in vitro bioassay system. Research it as more potent than native somatostatin in that in vitro context, though this claim rests on a single assay-level observation.
Evidence map
| Evidence layer | Grade | What it supports |
|---|---|---|
| Human | None identified | No human trial or observational data identified |
| Animal | None identified | No animal model efficacy data identified |
| In vitro | Weak | Somatostatin-like immunoactivity and in vitro bioactivity; reported as more potent than somatostatin in one bioassay context |
| Computational | None identified | No structure prediction or docking data identified |
| Mechanism | Plausible | Structural and immunological similarity to somatostatin suggests shared receptor or pathway involvement; no direct receptor-binding confirmation is extracted in this card |
Claim check
| Claim | Verdict | Evidence layer | Confidence |
|---|---|---|---|
| Displays somatostatin-like immunoreactivity and in vitro bioactivity | Supported (in vitro) | In vitro | Low — single source, sparse detail |
| More potent than native somatostatin | Weak (in vitro) | In vitro | Low — single in vitro bioassay; no replicated or comparative binding data extracted |
| Efficacy in animal or human systems | Not established | None | High — no animal or human data identified |
Assay conditions
This section reports conditions referenced in the available literature. It does not establish animal or human exposure.
| Context | System | Assay condition | Timepoint | Endpoint | Limitation |
|---|---|---|---|---|---|
| In vitro bioassay | Not individually specified in source | Not individually extracted in source | Not reported | Somatostatin-like bioactivity; relative potency versus somatostatin | Single assay observation; assay design, concentration, and comparator details are not extracted |
Assay limitations
- The in vitro bioassay design, cell system, peptide concentration, and specific endpoint are not individually described in the available literature.
- Relative potency versus somatostatin is described as an in vitro assay finding; this does not establish in vivo activity, receptor subtype selectivity, or systemic biological relevance.
- No animal toxicology, pharmacokinetic, or human safety data are identified.
- In vitro activity in a somatostatin bioassay does not establish equivalence to native somatostatin pharmacology in intact biological systems.
Mechanism
Somatostatin-25 peptide shares immunological and apparent biological characteristics with native somatostatin, a cyclic neuropeptide that acts as an inhibitory regulator of growth hormone, insulin, glucagon, and other secretory signals. Somatostatin exerts its effects through a family of G protein-coupled receptors (somatostatin receptors SSTR1–SSTR5), inhibiting adenylyl cyclase, modulating ion channels, and suppressing secretion in endocrine and exocrine tissues. The structural and immunological similarity of somatostatin-25 peptide to native somatostatin suggests potential interaction with these pathways, but specific receptor binding, subtype selectivity, or pathway activation data for this peptide are not individually extracted from the attached source. Target identity and activity type remain inferred from assay context rather than confirmed by dedicated binding or functional studies cited in this card.
Chemistry
| Field | Value |
|---|---|
| Amino-acid sequence (single-letter) | SNPAMAPRERKAGCKNFFWKTFTSC |
| Amino-acid sequence (three-letter) | H-Ser-Asn-Pro-Ala-Met-Ala-Pro-Arg-Glu-Arg-Lys-Ala-Gly-Cys-Lys-Asn-Phe-Phe-Trp-Lys-Thr-Phe-Thr-Ser-Cys-OH |
| Length | 25 amino acids |
| Topology | Linear (as reported; no cyclization noted in source) |
| Cysteine residues | Two cysteines present (positions 14 and 25); disulfide status not explicitly stated in source |
| Source organism | Ovine (sheep) hypothalamus |
| Molecular weight | Not reported in source |
| Formula | Not reported in source |
| CAS | Not reported in source |
| Sequence confidence | Needs review — single source; cysteine disulfide bonding status not clarified |
Open questions
- Animal translation: No animal model data for this peptide are attached. Whether the in vitro bioactivity translates to in vivo effects has not been established in available literature material.
- Receptor identity: The specific somatostatin receptor subtype(s) through which this peptide may act have not been identified in the attached source. Whether it binds SSTR1–SSTR5 or a subset has not been extracted.
- Disulfide bond status: Published research sequence contains two cysteine residues (C14 and C25). Whether these form an intramolecular disulfide bond — as in native somatostatin-14 — has not been explicitly characterized in the available literature.
- Potency claim replication: The in vitro potency advantage over native somatostatin is reported in a single literature reference from 1980; independent replication in more defined assay systems has not been extracted in this card.
- Structural characterization: No three-dimensional structure or receptor co-structure data are identified.
▸full evidence table2 metrics
| metric | value | tool |
|---|---|---|
| ipTM | 0.8215914964675903 | boltz-2 |
| ranking score | 0.803978443145752 | boltz-2 |
▸structural qualityopenfold3
| metric | value | note |
|---|---|---|
| gpde | 0.632 | global PDE — lower = better |
| disorder | NaN | fraction disordered |
▸3-letter notation
▸recipeboltz-2 1.0
| parameter | value |
|---|---|
| model | boltz-2 1.0 |
| weights | — |
| hardware | nvidia_nim_api |
| mlx version | — |
| python | — |
| random seed | — |
| msa strategy | none |
| diffusion samples | 1 |
| runtime | — |
| predicted by | mlx@peptide |
| predicted at | 2026-04-24 |
▸citationbibtex
@peptide{pep10657,
sequence = {SNPAMAPRERKAGCKNFFWKTFTSC},
target = {ghsr},
author = {peptidemodel},
year = {2026},
status = {computed}
}