The truth about peptides.

Peptides are small protein units that have very important biochemical as well as physiological functions within living systems – plant, animal and microorganism systems alike. To consider these proteins only in their capacity as cosmetic components would be to vastly underestimate one of nature’s most vital ingredients.

Peptide synthesisStudies have shown that they contribute significantly to a number of physiological processes, including the makeup of enzymes, receptors, hormones and some antibiotics, all of which have protein components. Enzymes have become key ingredients in the drug industry, for the treatment and therapeutic intervention for various diseases, including psychological conditions like depression.

Basic facts

The peptide is a small molecules – they can have as few as two amino acids. The types, physical and chemical properties of peptides vary – depending on the specific amino acids that they contain and how these amino acids are constituted. The maximum number is 50; above 50, the structures are considered full proteins. During the lifespan of human beings, various factors cause one to start aging, not just on the skin, but throughout the body. With this process, the body produces fewer retinoids which mean less collagen and elastin production, which is what causes thinning on the skin and eventual fine lining and wrinkling.


During specific synthesis, one amino acid carboxyl group (COOH) joins to the adjacent amino acids amino group (NH2). The carboxyl group loses its hydroxyl ion (OH-) and the amino group loses a hydrogen ion (H+), which combine to form a water molecule. Because of that, the process is known as dehydration.

This is what happens during protein formation in living things, but it can also be readily simulated in a laboratory set-up in mock biological conditions. There are only two ways for these to be synthesized in a lab: liquid phase and solid phase synthesis.


They are classified according to how they function in a living system.


1. Hormones are responsible to intra-cellular and intercellular signal transfer to initiate specific reactions.

2. Alkaloids, which are found in shellfish, plant, and fungi, are defense molecules.

3. Antibiotics are small proteins designed to interfere with the way bacterial systems function, limiting their growth.

4. Neuropeptides are produced in nerve tissues and are important for signaling between cells located far apart from each other. Some industrially synthesized neuropeptides have been used to mimic the action of Botulinum neurotoxin (Botox) in the prevention of muscle contraction signals thereby relaxing the muscles. This is still under study, however.Checkout latest news and details at

5. Amino acids are important for cosmetology since they can relay a signal between the skin’s epidermal layer and the dermal layer. Age weakens the skin’s communications network, and help to make up for the deficit.

What Is GHRP-2?

GHRP-2 is short for growth hormone releasing peptide-2. GHRP-2 is a synthetic peptide consisting of just seven amino acids (D-Ala-D-(β-naphthyl)-Ala-Ala-Trp-D-Phe-Lys). It is part of a series of compounds developed by Polygen (Germany) and Tulane University (United States) in an effort to create easily administered analogues of growth hormone releasing hormone1 . GHRP-2 is also known as GPA-748, pralmorelin, KP-102 D, DP-102 LN, DP-102D, and KP-102LN.

Effects of GHRP-2

GHRP-2 is a growth hormone (GH) secretagogue. It is NOT an agonist of the growth hormone releasing hormone receptor (GHRHR), but rather is an agonist of the ghrelin receptor. As a GH secretagogue, GHRP-2 causes the release of growth hormone, which in turn causes the release of insulin-like growth factor-1 (IGF-1) and a host of other hormones. The major effects of stimulating growth hormone release include hyperplasia (growth in cell numbers) and hypertrophy (growth in cell size) in bone and skeletal muscle. Additional effects include improve function of heart muscle (cardiomyocytes), increased lipid metabolism (fat loss), and decreases in blood sugar (glucose).

By stimulating ghrelin receptors, How does GHRP-2 work? And, also acts as an appetite stimulant. Research in lean, healthy human males, published in the Journal of Clinical Endocrinology and Metabolism, found a 35.9% increase in appetite among subjects receiving GHRP-2 injections compared to saline injections2 . Ghrelin is a known appetite stimulant and has been found to regulate growth hormone secretion as well.

Clinical Applications

GHRP-2 is currently under investigation in Japan as a treatment for short stature. It is under investigation in the United States as a potential treatment for GH deficiency. Tulane University currently holds a patent, issued in October 2002, for protection of its series of synthesized GH-releasing peptides. The patent includes GHRP-2.


A 2004 study on rats found that GHRP-2 does not have any significant side effects on nervous system, smooth muscles, respiratory system, cardiovascular system, digestive system, or urinary system (kidneys). The hope is to eventually use GHRP-2 to both diagnose GH deficiency and treat short stature that results from GH deficiency3 . See detailed updates at


  1. Pralmorelin: GHRP 2, GPA 748, growth hormone-releasing peptide 2, KP-102 D, KP-102 LN, KP-102D, KP-102LN. Drugs RD5, 236-239 (2004).
  1. Laferrère, B., Abraham, C., Russell, C. D. & Bowers, C. Y. Growth Hormone Releasing Peptide -2 (GHRP-2), like ghrelin, increases food intake in healthy men. J. Clin. Endocrinol. Metab.90, 611-614 (2005).
  1. Furuta, S. et al. General Pharmacology of KP-102 (GHRP-2), a Potent Growth Hormone-Releasing Peptide. Arzneimittelforschung54, 868-880 (2011).

Sermorelin: A great peptide?

Sermorelin is a synthetic analogue of the naturally occurring hormone known as growth hormone releasing hormone (GHRH). Sermorelin is used as a diagnostic agent in clinical medicine to assess growth hormone secretion. It is known by the trade name Geref and also by the name Growth Hormone Releasing Factor (1-29), which is abbreviated to GRF (1-29).

Structure and Function

Sermorelin consists of the first 29 amino acids of GHRH. Research in the early 1980s demonstrated that the first 29 amino acids of the full GHRH peptide (44 amino acids long) were capable of eliciting a full growth hormone (GH) response from the anterior pituitary gland. The shortened sermorelin has a limited half-life compared to GHRH, which means that it is cleared from the blood stream quickly. The short half-life of sermorelin makes it an ideal molecule for testing GH release because it does not have long-lasting effects and thus is relatively benign.

In limited cases, sermorelin is useful in treating growth hormone deficiency. In general, the peptide is used in adult-onset GH deficiency and rarely to treat childhood forms of the disorder. GH deficient children will not experience a large enough improvement in GH secretion when only secretagogues like sermorelin are used. Instead, children often require direct supplementation with GH. Recently, sermorelin has seen increased use in longevity medicine, a specialty focusing on improving physical performance and health in the elderly1 .

Amino Acid Sequence of Sermorelin:


Amino Acid Sequence of GHRH:

Tyr-Ala-Asp-Ala-Ile-Phe-Thr-Asn-Ser-Tyr-Arg-Lys-Val-Leu-Gly-Gln-Leu-Ser-Ala-Arg -Lys-Leu-Leu-Gln-Asp-Ile -Met-Ser-Arg-Gln-Gln-Gly-Glu-Ser-Asn-Gln-Glu-Arg-Gly-Ala-Arg-Ala-Arg-Leu-NH2

Effects of Sermorelin

Because sermorelin causes the release of GH from the anterior pituitary gland, it mimics effects of any other GH secretagogue. Examples of sermorelin effects include

.   Increased released of insulin-like growth factor-1 (IGF-1) from the liver,

.   Increases in muscle mass and bone density via both hypertrophy (cell size increases) and hyperplasia (increases in numbers of cells),

.   Increased fat metabolism and weight loss,

.   Improved cardiovascular function,

.   Improved renal function, and

.   Improved cognitive function.


The drug is not prohibited for use in off-label prescribing, which means that it can be prescribed by physicians for uses other than what it is specifically marketed for. This contrasts markedly with GH, which can only be prescribed for a fixed number of conditions and cannot legally be used off label.

Benefits of Sermorelin over Growth Hormone

One of the reasons that sermorelin has become popular in adults is that it has fewer side effects than GH. In particular, overdoses with sermorelin are extremely uncommon because its effects are still subject to normal negative feedback mechanisms that control endogenous GHRH. Other benefits of sermorelin include mimicking normal physiologic release of GH, low risk of tachyphylaxis (rapidly diminishing response to successive doses of a drug), and preservation of the GH neuroendocrine axis1 . Get full information at


  1. Walker, R. F. Sermorelin: A better approach to management of adult-onset growth hormone insufficiency? Clin. Interv. Aging1, 307-308 (2006).