Peptides for Hair Growth Research

Hair loss treatment in the United States was worth $3.6 billion in 2022 and was projected to growth at roughly 8% per year through 2028. Treatment solutions for hair loss, at present, include topical and oral medications, surgery, and laser-based regrowth treatments. Unfortunately, none of these options is ideal as the currently available medications are only marginally effective, surgery has high failure rates, and laser treatments tend to be both expensive and of limited efficacy. As a result of the demand for hair loss treatment and because current options are inadequate, hair growth research is a highly funded and cutting-edge field.

Until very recently, peptides played only a marginal role in hair growth treatment, in no small part because science had a very poor understanding of the mechanisms leading to hair loss. A breakthrough research article in 2021, however, revealed that peptides may play a fundamental role in hair growth and regrowth. The result has been a dramatic increase in the study of peptides for hair growth. Here is a look at some of the best peptides for hair growth research and what they have taught science about the surprisingly complex biology of hair growth.

Hair Growth Cycle

The growth and shedding of hair take place as part of a three-phase cyclic process. This process applies to hair on the human head, but also body hair, eyelashes, eyebrows, and other hair. The three stages of hair growth are anagen, catagen, and telogen. Healthy hair progresses through these stages in a cyclic pattern, moving from one to the next without getting stuck on any single cycle. In hair loss conditions, hairs prematurely leave the anagen (growth) phase and enter the resting (telogen) phase. This results in a dramatic decrease in or cessation of hair growth followed by overall thinning as the hairs are shed and not replaced.

While it isn’t fully understood why hair gets trapped in the telogen phase, there are many clues to potential causes. For starters, the male hormone DHT (a derivative of testosterone) appears to play an important role in hair loss. DHT is thought to diminish blood supply to hair follicles and perhaps increase inflammation that leads to hair loss.

Another potential cause of hair loss is changes in nutrient delivery patterns to the scalp. Research suggests that decreased levels of certain B vitamins, for instance, can profoundly impact the health of hair and hair follicles. Changes in nutrient delivery can be caused by changes in blood supply or by inflammation that blocks transport.

Finally, hair loss is likely caused by changes at the level of the DNA. Though the mechanisms by which this may occur have yet to be elucidated, scientists speculate that epigenetic changes in DNA expression patterns likely alter the hair growth cycle. For instance, changes in the expression of hormones like DHT or growth hormone are thought to impact collagen and elastin production as well as blood vessel supply. Thus, the underlying cause of much hair loss may be alterations in DNA expression patterns that manifest as changes in hormone levels and blood vessel growth.

Of note, knowing the cyclic nature of hair growth has been of limited utility to scientists. This is primarily because there has been little success in delineating what causes hair follicles to move from one stage of the cycle to another. Recent research on the adiponectin peptide, however, has offered science the first glimpse into truly understanding the mechanisms by which hair follicles transition from growth to rest shedding and back again. Here is a look at some of the best peptides for hair growth research that are helping to shed light on how hair grows and how science might be able to overcome hair loss.

Adiponectin

Adiponectin is a peptide hormone produce by white fat cells. It plays important roles in glucose and lipid metabolism and has long been of interest to scientists for its ability to regulate insulin sensitivity. Higher levels of adiponectin are associated with improve blood sugar levels and protection from the onset of diabetes. As it turns out, skin itself contains three adiponectin receptors and so scientists set out to learn what impact adiponectin has on the skin. What they found, in part, is that adiponectin causes the elongation of the hair shaft and increases levels of key growth hormones including vascular endothelial growth factor, insulin-like growth factor-1, and hepatocyte growth factor. Skin cells treated with adiponectin show increases in mRNA levels as well, suggesting that the peptide may alter DNA expression patterns[1].

Recently, a synthetic derivative of adiponectin, called APN5, has been developed. APN5 binds to the AdipoR1 receptor. AdipoR1 has long been known to mediate AMPK and PPAR-α activities, both of which are potent modulators of DNA expression patterns. Research shows that transdermal delivery of APN5 in mouse models leads to activation of AdipoR1 and concomitant hair growth. Hair follicles in the treatment group transitioned from telogen to anagen, suggesting that APN5 and the AdipoR1 may reverse the quiescence that occurs in hair cells as a result of aging and changes in hormone levels[2]. In the research, APN5 showed improvements in hair cycle scores comparable to those of minoxidil and roughly three times greater than the control. The exact mechanism of minoxidil on hair growth has never been understood. This recent research has scientists asking themselves if minoxidil’s effects on hair growth might be mediated through the AdipoR1 receptor. If this is true, then research using the APN5 peptide may have uncovered an important key to hair health, making it possible to target treatments in the future for preventing hair loss and regrowing lost hair.

BPC-157

BPC-157 is a synthetic derivative of naturally occurring body protection compound (BPC). BPC has been found to have several anti-inflammatory and wound healing effects. Research shows that it can accelerate wound healing, improve vascularity, and reduce tissue destruction.

Of course, an important aspect of wound healing is increased production of collagen. Collagen is a ubiquitous protein found in nearly every organ of the body. It is also found in hair where it plays important roles in protecting hair follicles from damage and supplies much needed amino acids to produce keratin. BPC-157 increases collagen formation while also increasing blood vessel growth. This results in enhanced supply of nutrients and collagen to hair follicles where they are needed[3]. BPC 157 isn’t just one of the best peptides for hair growth research, its profound healing properties make it one of the best peptides for wound healing research, tendon repair research, and inflammatory bowel disease research.

CJC-1295

CJC-1295 is a growth hormone secretagogue and it is just one of many. Research indicates that growth hormone, which is traditionally associated with muscle and long bone growth, has a profound effect on head and body hair growth. In fact, in those who are growth hormone deficient, supplementation has been shown to increase hair growth and decrease DHT concentrations. GH deficiency has even been associated with increases in 5-alpha reductase concentrations[4], [5]. 5-alpha reductase is the enzyme that converts testosterone to DHT. This tracks well with the fact that GH levels decline with age, roughly paralleling the time-related pattern of hair loss accelerating as we age and then plateauing. Other peptides that influence growth hormone and might also produce increases in hair growth include GHRP-2, GHRP-6, ipamorelin, sermorelin, and more. Any of these peptides could easily be included in the list of best peptides for hair growth research, with CJC-1295 standing in as an important and well-regarded representative of the whole group where hair growth is concerned.

GHK-Cu

GHK-Cu which is well known for its effects on skin health and appearance, might be one of the best peptides for hair growth research. After all, there is a reason why the peptide is found in many premium cosmetic and hair care products. Research shows that GHK-Cu tightens skin and improves the appearance of fine lines and wrinkles by increasing collagen and elastin production (both of which are important in hair growth and hair strength). It also reduces mottling and hyperpigmentation. As part of its effects on skin, however, GHK-Cu has a direct impact on the thickness of hair follicles.

There are a few ways in which GHK-Cu improves the health of hair follicles. First, it increases blood vessel growth. Diminished blood supply is one of the leading causes of hair loss and a major reason why our hair thins as we age. In early stages of hair growth, GHK-Cu stimulates capillary growth to hair follicles to improve nutrient delivery[6].

The second way in which GHK-Cu assists in promoting hair growth is possibly through a reduction in dihydrotestosterone (DHT). DHT is a primary driver of male pattern hair loss. GHK-Cu, in combination with other peptides, can inhibit 5-alpha-reductase, the enzyme that converts testosterone to DHT[7]. As a result, GHK-Cu can increase hair thickness and length.

Finally, CHK-Cu is a powerful anti-inflammatory. Research shows that reduction of inflammation in the scalp can help to reduce hair loss, increase hair density, and increase scalp vascularity. The anti-inflammatory effects of GHK-Cu may work in combination with its above effects to improve hair retention and even encourage hair regrowth.

TB-500/Thymosin Beta 4

TB-500 is a derivative of thymosin beta 4. Both peptides have been shown to affect DNA expression patterns and thus protein production. Research on thymosin beta 4 has revealed that the peptide, when over-expressed in mice, leads to accelerated hair growth[8]. It is likely that increased blood vessel growth in and around the hair follicles combined with increased protein expression due to DNA alterations are the primary mechanisms by which TB-500 and thymosin beta 4 increase hair growth.

Very recent research, in both mice and goats, shows that TB-500 can increase proliferation and migration of hair follicle stem cells, the cells that give rise to hair. It appears that TB-500 activates the hair follicle cycle transition, helping hair cells to shift from a quiescent state to one of growth and renewal[9]. By stimulating hair follicle stem cells, however, TB-500 is encouraging new hair follicles to grow rather than just encouraging existing follicles to move from telogen to anagen.

Peptides for Hair Growth Research: Summary

The peptides above are just some of those that have been found to have a positive impact on hair growth. As such, these peptides are of particular interest in hair growth research. Specifically, APN5, the synthetic derivative of adiponectin, may have offered one of the most profound advancements in hair growth research in several decades. The findings are new, so researchers are likely to rush to replicate them and to explore how other peptides interact with the AdipoR1 receptor. This opens the door for additional research into how the AdipoR1 receptor affects hair growth, which will, in turn, lead to the discovery of new molecular targets as well as the development of additional peptides for hair growth research. Ultimately, this opens the door to a much deeper understanding of hair growth itself.

Resources

[1] C. H. Won et al., “Hair Growth–Promoting Effects of Adiponectin In Vitro,” J. Invest. Dermatol., vol. 132, no. 12, pp. 2849–2851, Dec. 2012, doi: 10.1038/jid.2012.217.

[2] J. Ohn et al., “Discovery of a transdermally deliverable pentapeptide for activating AdipoR1 to promote hair growth,” EMBO Mol. Med., vol. 13, Sep. 2021, doi: 10.15252/emmm.202013790.

[3] S. Seiwerth et al., “BPC 157’s effect on healing,” J. Physiol. Paris, vol. 91, no. 3–5, pp. 173–178, 1997, doi: 10.1016/s0928-4257(97)89480-6.

[4] G. j. Blok, H. De Boer, L. j. g. Gooren, and E. a. Van Der Veen, “Growth hormone substitution in adult growth hormone-deficient men augments androgen effects on the skin,” Clin. Endocrinol. (Oxf.), vol. 47, no. 1, pp. 29–36, 1997, doi: 10.1046/j.1365-2265.1997.2021027.x.

[5] R. J. Witorsch and J. T. Edwards, “Comparison of effects of prolactin and growth hormone on adrenal 5alpha-reductase in hypophysectomized rats,” Proc. Soc. Exp. Biol. Med. Soc. Exp. Biol. Med. N. Y. N, vol. 151, no. 4, pp. 689–693, Apr. 1976, doi: 10.3181/00379727-151-39287.

[6] L. Pickart and A. Margolina, “Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data,” Int. J. Mol. Sci., vol. 19, no. 7, p. 1987, Jul. 2018, doi: 10.3390/ijms19071987.

[7] W. J. Lee, H. B. Sim, Y. H. Jang, S.-J. Lee, D. W. Kim, and S.-H. Yim, “Efficacy of a Complex of 5-Aminolevulinic Acid and Glycyl-Histidyl-Lysine Peptide on Hair Growth,” Ann. Dermatol., vol. 28, no. 4, pp. 438–443, Aug. 2016, doi: 10.5021/ad.2016.28.4.438.

[8] H.-J. Cha, D. Philp, S.-H. Lee, H.-S. Moon, H. K. Kleinman, and T. Nakamura, “Over-expression of thymosin beta 4 promotes abnormal tooth development and stimulation of hair growth,” Int. J. Dev. Biol., vol. 54, no. 1, pp. 135–140, 2010, doi: 10.1387/ijdb.082735hc.

[9] B. Dai, R.-N. Sha, J.-L. Yuan, and D.-J. Liu, “Multiple potential roles of thymosin β4 in the growth and development of hair follicles,” J. Cell. Mol. Med., vol. 25, no. 3, pp. 1350–1358, Feb. 2021, doi: 10.1111/jcmm.16241.