HGH Fragment 176-191
The original, unmodified version of the growth hormone fat-burning fragment — essentially the same concept as AOD-9604 but less stable and shorter-lasting. Contains the part of growth hormone responsible for fat metabolism without the parts that cause growth or blood sugar issues. Requires more frequent dosing than AOD-9604, and has even less clinical evidence supporting its effectiveness.
Dosage
250-500 mcg subcutaneous twice daily
Dosages shown are for research reference only. Always consult a qualified healthcare provider.
Administration
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Effects
Fat Metabolism
Contains the lipolytic domain of GH but lacks clinical trial support for efficacy.
IGF-1 Neutral
Does not stimulate IGF-1 production or cause growth-promoting effects.
Weight Loss
Theoretical fat-burning from the GH lipolytic domain, though clinical evidence is weak.
Mechanism of Action
HGH Fragment 176-191 is the unmodified C-terminal segment of human growth hormone, representing exactly the last 16 amino acids of the 191-amino-acid GH molecule. Research identified this region as containing the molecular determinants responsible for GH's lipolytic activity, independent of the N-terminal domain that binds the growth hormone receptor and drives IGF-1 production and tissue growth.
The fragment activates lipolysis in white adipose tissue through interaction with beta-adrenergic signaling pathways. This triggers the cAMP/protein kinase A cascade that phosphorylates and activates hormone-sensitive lipase and perilipin proteins on the surface of lipid droplets within fat cells. The result is the breakdown of stored triglycerides into free fatty acids and glycerol, which are released into circulation for oxidation by energy-demanding tissues such as skeletal muscle and the liver.
Because the fragment lacks the binding regions for the GH receptor (located in amino acids 1-175), it does not activate the JAK2-STAT5 signaling pathway responsible for hepatic IGF-1 synthesis, somatic growth, or the insulin-antagonistic effects of full-length growth hormone. However, the shorter half-life compared to AOD-9604 (which has an additional stabilizing tyrosine residue) means more frequent dosing is required, and clinical evidence supporting its efficacy in humans remains very limited.
Regulatory Status
Not FDA approved. Research compound only. Available through peptide suppliers.
Risks & Safety
Common
injection site irritation, headache, brief dizziness.
Serious
extremely limited clinical data, no long-term safety information.
Rare
allergic reactions.
Compare HGH Fragment 176-191 With
Research Papers
1Published: June 26, 2022
AI Summary
The HGH fragment 176-191 enhanced the toxicity of doxorubicin-loaded chitosan nanoparticles against breast cancer cells. The peptide helped target tumor-related proteins and increase drug accumulation at the tumor site.
Frequently Asked Questions
What is HGH Fragment 176-191?
The original, unmodified version of the growth hormone fat-burning fragment — essentially the same concept as AOD-9604 but less stable and shorter-lasting. Contains the part of growth hormone responsible for fat metabolism without the parts that cause growth or blood sugar issues. Requires more frequent dosing than AOD-9604, and has even less clinical evidence supporting its effectiveness.
What is HGH Fragment 176-191 used for?
The original, unmodified version of the growth hormone fat-burning fragment — essentially the same concept as AOD-9604 but less stable and shorter-lasting. Contains the part of growth hormone responsible for fat metabolism without the parts that cause growth or blood sugar issues. Requires more frequent dosing than AOD-9604, and has even less clinical evidence supporting its effectiveness.
What is the dosage for HGH Fragment 176-191?
Research: 250-500 mcg subcutaneous once or twice daily, on an empty stomach. Often cycled 8-12 weeks on, 4 weeks off. The short half-life typically requires twice-daily dosing for sustained effect.
What are the side effects of HGH Fragment 176-191?
Common: injection site irritation, headache, brief dizziness. Serious: extremely limited clinical data, no long-term safety information. Rare: allergic reactions.
How does HGH Fragment 176-191 work?
HGH Fragment 176-191 is the unmodified C-terminal segment of human growth hormone, representing exactly the last 16 amino acids of the 191-amino-acid GH molecule. Research identified this region as containing the molecular determinants responsible for GH's lipolytic activity, independent of the N-terminal domain that binds the growth hormone receptor and drives IGF-1 production and tissue growth. The fragment activates lipolysis in white adipose tissue through interaction with beta-adrenergic signaling pathways. This triggers the cAMP/protein kinase A cascade that phosphorylates and activates hormone-sensitive lipase and perilipin proteins on the surface of lipid droplets within fat cells. The result is the breakdown of stored triglycerides into free fatty acids and glycerol, which are released into circulation for oxidation by energy-demanding tissues such as skeletal muscle and the liver. Because the fragment lacks the binding regions for the GH receptor (located in amino acids 1-175), it does not activate the JAK2-STAT5 signaling pathway responsible for hepatic IGF-1 synthesis, somatic growth, or the insulin-antagonistic effects of full-length growth hormone. However, the shorter half-life compared to AOD-9604 (which has an additional stabilizing tyrosine residue) means more frequent dosing is required, and clinical evidence supporting its efficacy in humans remains very limited.
How is HGH Fragment 176-191 administered?
HGH Fragment 176-191 is administered via subcutaneous injection.
What is the half-life of HGH Fragment 176-191?
The half-life of HGH Fragment 176-191 is 0.5-1 hours.
Is HGH Fragment 176-191 legal?
Not FDA approved. Research compound only. Available through peptide suppliers.
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