#LipidMetabolism | #Metabolic | #Regenerative

hGH Fragment 176–191 — Research Overview (RUO)

hGH Fragment 176–191 is a synthetic peptide corresponding to the C-terminal region of human growth hormone. It is investigated primarily for its lipolytic effects on adipose tissue that appear mechanistically distinct from the anabolic and IGF-1–mediated actions of full-length hGH.

Peptide Name:

hGH Fragment 176–191

Type:

Synthetic Peptide Fragment

Sequence Length:

16 Amino Acids

Origin:

C-Terminal domain of human growth hormone

Primary Research Focus:

Lipid Metabolism & Adipose Tissue

Regulatory Status:

Research Use Only (RUO)

Molecular Weight:

~1,817.1 Da

Peptide Length:

16 Amino Acids

Amino Acid Sequence:

Tyr–Leu–Arg–Ile–Val–Gln–Cys–Arg–Ser–Val–Glu–Gly–Ser–Cys–Gly–Phe

Structure Note:

This sequence corresponds to residues 176–191 of native human growth hormone. A tyrosine residue is often added to the N-terminus in synthetic preparations to enhance stability.

Store powder at +4°C (short term) or -20°C (long term). Keep desiccated.

For laboratory research use only. Reconstitute using sterile bacteriostatic water consistent with established laboratory research protocols. Preparation should be performed under aseptic conditions. Reconstituted material is not intended for long-term storage.

Amino Acid Sequence:

Structural Origin & Relation to hGH

Content: The full human growth hormone molecule consists of 191 amino acids and exerts its biological effects through multiple functional domains:

N-Terminal Domain: Associated with insulin-like and anabolic signaling
C-Terminal Domain (176–191): Associated with anti-insulin and lipolytic activity

Fragment 176–191 is investigated to determine whether the beneficial metabolic effects of hGH can be isolated from the adverse effects linked to IGF-1 stimulation and systemic growth hormone exposure.

Lipid Metabolism & Adipose Tissue Research

Content: The primary investigational focus of Fragment 176–191 is its direct action on adipose tissue. In vitro and animal model studies have examined its ability to:

Increase expression of β3-adrenergic receptors (primarily in rodent models)
Stimulate lipolysis through enhanced triglyceride breakdown
Inhibit lipogenesis by downregulating enzymes such as fatty acid synthase

These effects appear to occur independently of classical growth hormone receptor activation, suggesting a non-canonical signaling pathway.

Glucose & Insulin-Related Research

Content: A major limitation of full-length hGH therapy is the induction of insulin resistance. Fragment 176–191 has been evaluated in obese (ob/ob) mouse models to assess its effects on glucose homeostasis. Key findings indicate:

No impairment of insulin sensitivity with chronic administration
Absence of IGF-1 elevation
Potential secondary improvements in glucose tolerance linked to reduced adipose mass

These findings contrast sharply with intact hGH.

Cartilage & Tissue-Level Research

Content: Beyond metabolic research, Fragment 176–191 has been explored in tissue engineering contexts. Studies have evaluated its effects on:

Chondrocyte proliferation
Mesenchymal stem cell activity
Cartilage regeneration when combined with hyaluronic acid scaffolds

Preclinical rabbit models suggest a potential role in osteochondral repair distinct from systemic growth hormone exposure.

Body Composition & Exploratory Human Research

Content: Early Phase II clinical trials evaluated AOD-9604, a stabilized derivative of Fragment 176–191, in human obesity. While weight-loss efficacy was variable compared to rodent models, safety outcomes were favorable, including:

No significant changes in IGF-1 levels
No impairment of glucose tolerance

These studies remain foundational references for fragment-based metabolic research.

RESEARCH LIMITATIONS

Stability: Native cysteine residues contribute to structural instability without modification
Receptor Identification: The precise receptor mediating lipolytic effects remains unidentified
Species Differences: Rodent lipolytic responses have not consistently translated to humans

KEY SCIENTIFIC REFERENCES

Ng, F. M., & Bornstein, J. (1978)
Hyperglycemic action of synthetic C-terminal fragments of human growth hormone.
American Journal of Physiology – Endocrinology and Metabolism.
Heffernan, M., et al. (2001)
Effects of human growth hormone and its lipolytic fragment (AOD9604) on lipid metabolism.
Endocrinology, 142(12), 5182–5189.
Kwon, D. R., & Park, G. Y. (2015)
Effect of intra-articular AOD9604 in rabbit osteoarthritis model.
Annals of Clinical & Laboratory Science.
Stier, H., et al. (2013)
Safety and tolerability of hexadecapeptide AOD9604 in humans.
Journal of Endocrinology and Metabolism.

The compound listed below is referenced in research contexts related to the mechanisms discussed in this article.

hGH Fragment 176–191 is a chemical reference standard intended strictly for in-vitro and laboratory research applications (e.g., adipocyte culture assays, tissue engineering models). It is not a drug, dietary supplement, or food additive, and is not intended for human consumption, injection, or therapeutic use. All handling must be performed by qualified professionals in a laboratory setting.

hGH Fragment 176–191 — Research Overview (RUO)

Peptide Name:

Type:

Sequence Length:

Origin:

Primary Research Focus:

Regulatory Status:

Molecular Weight:

Peptide Length:

Amino Acid Sequence:

Structure Note:

Amino Acid Sequence:

Age Verification Required

NAD+ Buffered

MOTS-c

KPV

KLOW Blend

Ipamorelin

HGH Fragment 176-191

Glutathione

GLOW Blend

GHK-Cu