What is Fragment 176-191?
Fragment 176-191 (also called HGH Fragment 176-191 or Frag 176-191) is a peptide fragment of human growth hormone consisting of amino acids 176 through 191 of the GH molecule. This C-terminal fragment is believed to contain the region of GH responsible for its lipolytic (fat-burning) effects.
Unlike full growth hormone, Fragment 176-191 is studied primarily for body composition effects without the growth-promoting or blood sugar impacts of complete GH.
Research Note: Fragment 176-191 is a research compound not approved by the FDA. Banned by WADA. This information is for educational purposes only.
Molecular Profile
Structure
The sequence corresponds to GH amino acids 176-191:
Tyr-Leu-Arg-Ile-Val-Gln-Cys-Arg-Ser-Val-Glu-Gly-Ser-Cys-Gly-Phe
Molecular Data
| Property | Value |
|---|---|
| Molecular Formula | C78H123N23O23S2 |
| Molecular Weight | ~1817.12 g/mol |
| CAS Number | 221231-10-3 |
| Amino Acids | 16 |
Mechanism of Action
Proposed Lipolytic Effects
The C-terminal region of GH is associated with:
- Stimulation of lipolysis
- Inhibition of lipogenesis
- Fat oxidation enhancement
- Adipocyte signaling
What It Lacks
Compared to full GH:
- No significant IGF-1 stimulation
- No growth effects
- Minimal blood sugar impact
- Limited anabolic effects
Research Applications
Body Composition Studies
Primary research focus:
- Fat loss mechanisms
- Targeted lipolytic effects
- Metabolic studies
- Weight management research
Comparison with Full GH
| Effect | Fragment 176-191 | Full Growth Hormone |
|---|---|---|
| Fat Loss | Yes | Yes |
| Muscle Growth | No | Yes |
| IGF-1 Increase | No | Yes |
| Blood Sugar | Minimal effect | Can increase |
| Growth Promotion | No | Yes |
Fragment 176-191 vs AOD-9604
These are closely related peptides:
| Aspect | Fragment 176-191 | AOD-9604 |
|---|---|---|
| Sequence | Native 176-191 | 177-191 + Tyr |
| Modification | None | N-terminal Tyr |
| Clinical Data | Limited | Phase 2 trials |
| Research | Fitness-focused | Pharmaceutical |
Summary
Fragment 176-191 offers a way to study GH's lipolytic effects in isolation, without the full spectrum of GH activity.
Key Points:
- Classification: HGH C-terminal fragment
- Primary Focus: Fat metabolism research
- Advantage: No IGF-1 or growth effects
- Status: Research compound, not approved