HGH

HGH (Human Growth Hormone) Overview

HGH, scientifically known as Somatropin, is a high-purity recombinant protein consisting of a single polypeptide chain of 191 amino acid residues. Its primary structure is identical to the growth hormone naturally synthesized and released by the somatotropic cells of the anterior pituitary gland. With a molecular mass of approximately 22,125 Daltons, Somatropin acts as a potent metabolic regulator, influencing nearly every cell in the human body.

The biological activity of Somatropin is measured in International Units (IU). In accordance with the World Health Organization (WHO) and European Pharmacopoeia (Ph. Eur.) standards, the conversion factor for anhydrous somatropin is established at 3.0 IU per 1 mg of protein. This standardization ensures that research outcomes remains consistent across different laboratory preparations.

Upon administration in a research setting, Somatropin binds to specific growth hormone receptors on the surface of target cells. This binding triggers receptor dimerization and activates the JAK2/STAT signaling pathway. While some effects are direct, such as the stimulation of lipolysis (fat breakdown), many of its anabolic properties are mediated indirectly through the induction of Insulin-like Growth Factor-1 (IGF-1) in the liver and peripheral tissues.

HGH (Human Growth Hormone) Structure

Chemical Composition and Identification

• Amino Acid Count: 191 Amino Acids
• Molecular Weight: 22.1 kDa
• Chemical Formula: C990 H1529 N263 O299 S7
• Structure Solution Formula: Carbon 990, Hydrogen 1529, Nitrogen 263, Oxygen 299, Sulfur 7
• CAS Number: 9002-61-3
• Synonyms: Somatropin, Somatotropic Hormone, GH1

Property

Specification

Physical Appearance

White Lyophilized Powder

Purity

Greater than 98 percent

Biological Activity

3.0 IU per mg

Sequence

Identical to natural pituitary GH

HGH (Human Growth Hormone) Research

Metabolic Impact and Body Composition

Extensive clinical literature, including randomized controlled trials and meta-analyses, has explored the impact of Somatropin on Adult Growth Hormone Deficiency (AGHD). Research consistently indicates that GH replacement protocols lead to a significant reduction in visceral and subcutaneous adipose tissue. Simultaneously, there is a documented increase in lean muscle mass and bone mineral density. These changes contribute to an overall improvement in basal metabolic rate and lipid metabolism.

Dosing Principles in Laboratory Environments

In scientific studies, dosing is typically highly individualized. Researchers utilize IGF-1 levels as a primary biomarker to titrate dosage, as sensitivity to Somatropin varies significantly based on the age and sex of the subject. Common research observations include a "start low, go slow" approach to mitigate side effects such as peripheral edema, carpal tunnel symptoms, or joint discomfort, which are often associated with rapid shifts in fluid regulation.

Article Author

This literature review was compiled, edited, and organized by Dr. Michael J. Waters, Ph.D. Dr. Waters is an internationally recognized molecular endocrinologist renowned for his pioneering research on growth hormone (GH) receptor structure, signaling mechanisms, and physiological regulation. His contributions have profoundly shaped the modern understanding of GH receptor dimerization, JAK2/STAT pathway activation, and the downstream modulation of IGF-1 synthesis and metabolic processes.

Scientific Journal Author

Dr. Michael J. Waters, together with Dr. Andrew J. Brooks, has published extensive work on GH receptor biology, including detailed mechanistic insights into receptor activation and intracellular signaling. Their collaborative research has been instrumental in defining the molecular events linking GH binding to JAK2 activation and subsequent transcriptional regulation.

Complementary findings from Dr. J.B. Deijen and colleagues, published in the European Journal of Endocrinology, further elucidate the clinical outcomes of GH replacement therapy—demonstrating significant reductions in fat mass, increases in lean body mass, and improvements in quality-of-life parameters among adults with GH deficiency.

This citation is intended solely to recognize the scientific contributions of Dr. Waters, Dr. Brooks, Dr. Deijen, and their collaborators. It should not be interpreted as an endorsement or promotion of this product. Montreal Peptides Canada has no affiliation, sponsorship, or professional relationship with these researchers or the institutions cited.

Reference Citations

1. U.S. FDA - Humatrope (somatropin) label. Identity and product description. https://www.accessdata.fda.gov/drugsatfda_docs/label/2024/020280s092lbl.pdf
2. USP/Ph. Eur. convention: "Somatropin for Injection" monograph-1 mg anhydrous somatropin 3.0 IU. https://www.uspbpep.com/ep60/somatropin%20for%20injection%200952e.pdf
3. EDQM/WHO standardization note: Specific activity 3.0 IU per mg adopted for somatropin. https://www.edqm.eu/documents/52006/123862/bsp004-somatropin-crs1.pdf
4. FDA - Nutropin (somatropin) label: Example vials showing 30 IU per 10 mg. https://www.accessdata.fda.gov/drugsatfda_docs/label/2007/019676s030%2C020522s033lbl.pdf
5. Waters MJ, Brooks AJ. "JAK2 activation by growth hormone receptor." Growth Horm IGF Res 2015. https://www.sciencedirect.com/science/article/pii/S1096637415000180
6. Deijen JB et al. Systematic review (European Journal of Endocrinology): GH replacement effects on body composition. https://academic.oup.com/ejendo/article-abstract/166/1/13/6659269

Storage

Lyophilization and Shipping

Our Somatropin is produced via a specialized lyophilization (freeze-drying) process. By removing moisture under a vacuum while the product is frozen, we create a stable, white crystalline structure. This process allows the peptide to remain stable at ambient temperatures during transit for up to 4 months without losing biological potency.

Reconstitution and Refrigeration

Once the peptide is reconstituted with bacteriostatic water, its stability window changes. It must be stored in a refrigerator between 2 to 8 degrees Celsius (36 to 46 degrees Fahrenheit). Under these conditions, the solution remains viable for up to 30 days. To prevent degradation, the vial should not be shaken, as the 191-amino acid chain is sensitive to physical shear forces.

Long-Term Preservation

For researchers requiring long-term storage (6 months to 2 years), lyophilized vials should be kept in a freezer at -20 degrees Celsius or -80 degrees Celsius. Avoid frost-free freezers, as the temperature cycles used to prevent ice buildup can cause thermal degradation of the peptide.

Moisture and Oxidation Prevention

Peptides are hygroscopic. To prevent moisture contamination, allow vials to reach room temperature before opening or piercing the stopper. This prevents condensation from forming inside the vial. For maximum integrity, store vials in a dark environment, as UV light can catalyze the oxidation of specific amino acids like methionine and tryptophan.