HGH Fragment 176-191

HGH Fragment 176-191 Metabolic & Systemic Energy Profile

HGH Fragment 176-191 is fundamentally integrated into the modulation of mammalian metabolism, forcing biological networks toward lipolysis, enhanced ATP synthesis, and profound systemic energy mobilization.

Pharmacological Architecture

Parameter	Value
Molecular Formula	C78H125N23O23S2
Molecular Mass	1817.1 g/mol
Assay Purity	>99.0%
Appearance	White lyophilized powder

Figure 1: Cellular Action of HGH Fragment 176-191

Metabolic Transduction Pattern

Detailed cascade of actions governing its systemic thermogenic profile:

1. Derived exclusively from the terminal sequence of the full Human Growth Hormone molecule.
2. Replicates the core lipolytic (fat-burning) domain of HGH without stimulating IGF-1 receptors.
3. Binds specifically to beta-3 adrenergic receptors embedded within white adipose tissue.
4. Forces immediate triglyceride breakdown and directly prevents new lipogenesis.
5. Produces pure fat oxidation without causing insulin resistance or cartilage growth.

Figure 2: Rate of Systemic Lipolysis & Output

Primary Research Results

• Outcome 1: Universally utilized to mimic the profound fat loss of Growth Hormone without the metabolic side effects.
• Outcome 2: Maintains perfectly stable blood glucose profiles even under extreme dosing protocols.
• Outcome 3: Demonstrates zero effect on cellular proliferation or tissue expansion unlike full-sequence HGH.

The Lipolytic Domain of Growth Hormone

HGH Fragment 176-191 (AOD-9604) is a modified 16-amino acid peptide corresponding to the C-terminal region of human growth hormone (amino acids 176–191). This specific fragment was identified through systematic truncation studies as the minimal sequence responsible for GH’s fat-metabolizing activity, completely divorced from its growth-promoting (anabolic) and diabetogenic effects. The fragment mimics the way natural growth hormone regulates fat metabolism by stimulating lipolysis (fat breakdown) and inhibiting lipogenesis (fat formation) without affecting blood glucose or insulin sensitivity.

1. Fragment 176-191 stimulates beta-3 adrenergic receptor-mediated lipolysis in adipocytes through a mechanism distinct from the GH receptor (GHR) signaling that drives IGF-1 production.
2. Hormone-sensitive lipase (HSL) activity increases in white adipose tissue, mobilizing stored triglycerides into free fatty acids and glycerol.
3. De novo lipogenesis is simultaneously inhibited by suppressing acetyl-CoA carboxylase (ACC) activity, reducing new fat synthesis.
4. Unlike full-length GH, Fragment 176-191 does not increase serum IGF-1, eliminating the proliferative and diabetogenic concerns of GH therapy.
5. The fragment does not compete for GHR binding and does not suppress endogenous GH pulsatility, preserving normal somatotroph axis function.

Research Evidence & Applications

• Obese Rodent Models: Fragment 176-191 reduced body fat by 50% in ob/ob mice over 2 weeks without affecting food intake, lean mass, or blood glucose levels.
• Human Clinical Data: Phase 2 studies (as AOD-9604) in obese subjects showed statistically significant weight loss versus placebo at 1 mg/day oral dosing over 12 weeks.
• No Hyperglycemia: Unlike full-length GH, the fragment does not impair glucose tolerance or insulin sensitivity at any dose tested, confirmed in glucose clamp studies.
• Half-Life: The unmodified fragment has a short half-life (~7 minutes), necessitating daily or twice-daily subcutaneous administration in research protocols.
• Combination: Often stacked with CJC-1295/Ipamorelin in body composition research protocols, where the fragment targets fat loss while GHRP/GHRH peptides support lean mass.